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MK 8G27 Gel Battery Measurements

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  • Gerard (Gary) Carlson
    Greetings all: I measured the voltages of my?twelve MK 8G27 Gels. The pack is about four years old and has about 30,000 miles on it. The batteries are numbered
    Message 1 of 21 , Feb 16, 2008
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      Greetings all:

      I measured the voltages of my?twelve MK 8G27 Gels.
      The pack is about four years old and has about 30,000 miles on it.

      The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
      batteries 6 to 12 are in back.? It appears that the front battery box
      is a rough neighborhood.? I had an assistant record the battery voltages
      for the draw test while I drove and used the economy knob to limit
      the current to 100 amps. The battery voltages are listed in order starting
      with battery number 1.

      Voltage after full charge, no load,?sitting overnight at about 60 degrees? F.
      13.24
      13.22
      13.14
      13.26
      13.24
      13.26
      13.23
      13.20
      13.20
      13.22
      13.29
      13.22

      Voltage after full charge with 100 amp draw at about 60 degrees F.
      11.74
      11.71
      11.68
      11.85
      11.80
      11.81
      11.80
      11.83
      11.79
      11.79
      11.77
      11.74

      Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.
      11.04
      7.71
      4.5
      8.93
      8.79
      11.38
      11.49
      11.48
      11.43
      11.48
      11.22
      11.42

      Note that four of the five batteries in the front box are about dead.? I assume
      that a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.

      I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.

      Any comments?

      Sincerely,
      Gary Carlson
      ID License:? AMPEATR
      1992 Solectria Force




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    • Peter Fletcher
      Wow! - Nice battary work. I realized you have a 1993 Force- Sence I have a 1993 Force I would love to see a pic of your motor compartment. When I got my force
      Message 2 of 21 , Feb 16, 2008
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        Wow! - Nice battary work.
        I realized you have a 1993 Force- Sence I have a 1993 Force
        I would love to see a pic of your motor compartment.
        When I got my force all the components had been unmounted by previous
        UNR students!!!! I have remounted everything. looks clean.
        I'll post a pic soon of my Motor Compartment.
        Peter Fletcher 1993 Force.
        With Permanent Magner Motor.



        To: solectria_ev@yahoogroups.comFrom: gjc0@...: Sat, 16 Feb 2008 22:29:09 -0500Subject: [solectria_ev] MK 8G27 Gel Battery Measurements




        Greetings all:I measured the voltages of my?twelve MK 8G27 Gels.The pack is about four years old and has about 30,000 miles on it.The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and batteries 6 to 12 are in back.? It appears that the front battery boxis a rough neighborhood.? I had an assistant record the battery voltagesfor the draw test while I drove and used the economy knob to limitthe current to 100 amps. The battery voltages are listed in order startingwith battery number 1.Voltage after full charge, no load,?sitting overnight at about 60 degrees? F. 13.2413.2213.1413.2613.2413.2613.2313.2013.2013.2213.2913.22Voltage after full charge with 100 amp draw at about 60 degrees F.11.7411.7111.6811.8511.8011.8111.8011.8311.7911.7911.7711.74Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.11.047.714.58.938.7911.3811.4911.4811.4311.4811.2211.42Note that four of the five batteries in the front box are about dead.? I assumethat a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.Any comments?Sincerely,Gary Carlson ID License:? AMPEATR1992 Solectria Force__________________________________________________________More new features than ever. Check out the new AOL Mail ! - http://webmail.aol.com[Non-text portions of this message have been removed]






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      • jim donovan
        Gary: You are having much the same volt reading I had last year at this time. Do you use/have the battery thermal management system to warm the batteries?
        Message 3 of 21 , Feb 17, 2008
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          Gary:

          You are having much the same volt reading I had last year at this time. Do you use/have the battery thermal management system to warm the batteries? After doing some work last year, I found out that my front battery box heater was designed to get too hot and basically boiled the batteries. In working with an electronics store I found that the "thermostat" in the little black box was the wrong one (it allowed the box to get too warm). I replaced it with the next size down and replaced the two center batteries (OK - a different conversation here - replaced two out of 13 batteries is not good but was a better "test" of my theories that the expense warranted) and have put 10,000 miles on the pack since then. My "test" worked. I confirm battery box temperatures with an indoor/outdoor AAA battery loaded thermometer and have the outside wired lead in each of the battery boxed. Temperature dropped from ~140 to ~90. The batteries seem to work much better.

          Jim
          Westwood, KS


          "Gerard (Gary) Carlson " <gjc0@...> wrote:
          Greetings all:

          I measured the voltages of my?twelve MK 8G27 Gels.
          The pack is about four years old and has about 30,000 miles on it.

          The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
          batteries 6 to 12 are in back.? It appears that the front battery box
          is a rough neighborhood.? I had an assistant record the battery voltages
          for the draw test while I drove and used the economy knob to limit
          the current to 100 amps. The battery voltages are listed in order starting
          with battery number 1.

          Voltage after full charge, no load,?sitting overnight at about 60 degrees? F.
          13.24
          13.22
          13.14
          13.26
          13.24
          13.26
          13.23
          13.20
          13.20
          13.22
          13.29
          13.22

          Voltage after full charge with 100 amp draw at about 60 degrees F.
          11.74
          11.71
          11.68
          11.85
          11.80
          11.81
          11.80
          11.83
          11.79
          11.79
          11.77
          11.74

          Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.
          11.04
          7.71
          4.5
          8.93
          8.79
          11.38
          11.49
          11.48
          11.43
          11.48
          11.22
          11.42

          Note that four of the five batteries in the front box are about dead.? I assume
          that a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.

          I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.

          Any comments?

          Sincerely,
          Gary Carlson
          ID License:? AMPEATR
          1992 Solectria Force

          __________________________________________________________
          More new features than ever. Check out the new AOL Mail ! - http://webmail.aol.com

          [Non-text portions of this message have been removed]






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        • Gerard (Gary) Carlson
          Jim: No, I do not have any battery heaters in either the front or rear battery boxes.? I am wondering if I have the opposite problem that you did.? You said
          Message 4 of 21 , Feb 17, 2008
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            Jim:



            No, I do not have any battery heaters in either the front or rear battery boxes.? I am wondering if I have the opposite problem that you did.? You said that your front batteries got too hot.? I am wondering if my front batteries got too cold in the Boise winters (typically 20 to 30 degrees F).? Lead-acid batteries are at their best at 80 degrees F.? I wonder if there was a temperature mismatch between the front and rear boxes.? The front batteries would be colder than the rear and become more deeply discharged.? During charging, they would be slightly undercharged because the charger's temperature probe is located in the rear box.

            I am considering adding a little insulation to the front box IF I can fit it.? After getting 30,000 miles, I am wondering if the expense of battery heaters is really worth it.? I also have no battery equalization system like PakTrack.

            Jim:? How many miles were you able to get from your battery pack?

            Sincerely
            Gary?Carlson
            1992 Solectria Force
            ID License:? AMPEATR
            gjc0@...


            -----Original Message-----
            From: jim donovan <donovan66205@...>
            To: solectria_ev@yahoogroups.com
            Sent: Sun, 17 Feb 2008 6:28 am
            Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements






            Gary:

            You are having much the same volt reading I had last year at this time. Do you use/have the battery thermal management system to warm the batteries? After doing some work last year, I found out that my front battery box heater was designed to get too hot and basically boiled the batteries. In working with an electronics store I found that the "thermostat" in the little black box was the wrong one (it allowed the box to get too warm). I replaced it with the next size down and replaced the two center batteries (OK - a different conversation here - replaced two out of 13 batteries is not good but was a better "test" of my theories that the expense warranted) and have put 10,000 miles on the pack since then. My "test" worked. I confirm battery box temperatures with an indoor/outdoor AAA battery loaded thermometer and have the outside wired lead in each of the battery boxed. Temperature dropped from ~140 to ~90. The batteries seem to work much better.

            Jim
            Westwood, KS


            "Gerard (Gary) Carlson " <gjc0@...> wrote:
            Greetings all:

            I measured the voltages of my?twelve MK 8G27 Gels.
            The pack is about four years old and has about 30,000 miles on it.

            The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
            batteries 6 to 12 are in back.? It appears that the front battery box
            is a rough neighborhood.? I had an assistant record the battery voltages
            for the draw test while I drove and used the economy knob to limit
            the current to 100 amps. The battery voltages are listed in order starting
            with battery number 1.

            Voltage after full charge, no load,?sitting overnight at about 60 degrees? F.
            13.24
            13.22
            13.14
            13.26
            13.24
            13.26
            13.23
            13.20
            13.20
            13.22
            13.29
            13.22

            Voltage after full charge with 100 amp draw at about 60 degrees F.
            11.74
            11.71
            11.68
            11.85
            11.80
            11.81
            11.80
            11.83
            11.79
            11.79
            11.77
            11.74

            Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.
            11.04
            7.71
            4.5
            8.93
            8.79
            11.38
            11.49
            11.48
            11.43
            11.48
            11.22
            11.42

            Note that four of the five batteries in the front box are about dead.? I assume
            that a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.

            I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.

            Any comments?

            Sincerely,
            Gary Carlson
            ID License:? AMPEATR
            1992 Solectria Force

            __________________________________________________________
            More new features than ever. Check out the new AOL Mail ! - http://webmail.aol.com

            [Non-text portions of this message have been removed]

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            [Non-text portions of this message have been removed]





            ________________________________________________________________________
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          • ehsif727
            Do you have air conditioning. I worry that the use of the air conditioning with its condenser blower blowing hot air on the front batteries might shorten their
            Message 5 of 21 , Feb 17, 2008
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              Do you have air conditioning. I worry that the use of the air
              conditioning with its condenser blower blowing hot air on the front
              batteries might shorten their life.
              Eric Fisher

              --- In solectria_ev@yahoogroups.com, "Gerard (Gary) Carlson "
              <gjc0@...> wrote:
              >
              > Greetings all:
              >
              > I measured the voltages of my?twelve MK 8G27 Gels.
              > The pack is about four years old and has about 30,000 miles on it.
              >
              > The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
              > batteries 6 to 12 are in back.? It appears that the front battery box
              > is a rough neighborhood.? I had an assistant record the battery voltages
              > for the draw test while I drove and used the economy knob to limit
              > the current to 100 amps. The battery voltages are listed in order
              starting
              > with battery number 1.
              >
              > Voltage after full charge, no load,?sitting overnight at about 60
              degrees? F.
              > 13.24
              > 13.22
              > 13.14
              > 13.26
              > 13.24
              > 13.26
              > 13.23
              > 13.20
              > 13.20
              > 13.22
              > 13.29
              > 13.22
              >
              > Voltage after full charge with 100 amp draw at about 60 degrees F.
              > 11.74
              > 11.71
              > 11.68
              > 11.85
              > 11.80
              > 11.81
              > 11.80
              > 11.83
              > 11.79
              > 11.79
              > 11.77
              > 11.74
              >
              > Voltage after 15 miles of range, current draw maxed out at 45 amps,
              60 F.
              > 11.04
              > 7.71
              > 4.5
              > 8.93
              > 8.79
              > 11.38
              > 11.49
              > 11.48
              > 11.43
              > 11.48
              > 11.22
              > 11.42
              >
              > Note that four of the five batteries in the front box are about
              dead.? I assume
              > that a number of cells in each of the four are dead.? Even 15,000
              miles earlier, battery #3 was always 0.1 volt lower than the highest
              on the pack.? This was probably an indication that it would be the
              first to die.
              >
              > I plan to change out the entire pack with new MK 8G27's.? I believe
              I got my money's worth out of these.? Being a real tightwad, I can
              still get a 10+ mile range between outlets.? I plan to do this during
              the next month while I wait for new batteries to arrive.
              >
              > Any comments?
              >
              > Sincerely,
              > Gary Carlson
              > ID License:? AMPEATR
              > 1992 Solectria Force
              >
              >
              >
              >
              > ________________________________________________________________________
              > More new features than ever. Check out the new AOL Mail ! -
              http://webmail.aol.com
              >
              >
              > [Non-text portions of this message have been removed]
              >
            • Gerard (Gary) Carlson
              Eric Fisher: Yes, I have air conditioning, but I use it infrequently. Sincerely, Gary Carlson ... From: ehsif727 To:
              Message 6 of 21 , Feb 17, 2008
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                Eric Fisher:



                Yes, I have air conditioning, but I use it infrequently.

                Sincerely,

                Gary Carlson


                -----Original Message-----
                From: ehsif727 <ehsif727@...>
                To: solectria_ev@yahoogroups.com
                Sent: Sun, 17 Feb 2008 9:39 am
                Subject: [solectria_ev] Re: MK 8G27 Gel Battery Measurements







                Do you have air conditioning. I worry that the use of the air
                conditioning with its condenser blower blowing hot air on the front
                batteries might shorten their life.
                Eric Fisher

                --- In solectria_ev@yahoogroups.com, "Gerard (Gary) Carlson "
                <gjc0@...> wrote:
                >
                > Greetings all:
                >
                > I measured the voltages of my?twelve MK 8G27 Gels.
                > The pack is about four years old and has about 30,000 miles on it.
                >
                > The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
                > batteries 6 to 12 are in back.? It appears that the front battery box
                > is a rough neighborhood.? I had an assistant record the battery voltages
                > for the draw test while I drove and used the economy knob to limit
                > the current to 100 amps. The battery voltages are listed in order
                starting
                > with battery number 1.
                >
                > Voltage after full charge, no load,?sitting overnight at about 60
                degrees? F.
                > 13.24
                > 13.22
                > 13.14
                > 13.26
                > 13.24
                > 13.26
                > 13.23
                > 13.20
                > 13.20
                > 13.22
                > 13.29
                > 13.22
                >
                > Voltage after full charge with 100 amp draw at about 60 degrees F.
                > 11.74
                > 11.71
                > 11.68
                > 11.85
                > 11.80
                > 11.81
                > 11.80
                > 11.83
                > 11.79
                > 11.79
                > 11.77
                > 11.74
                >
                > Voltage after 15 miles of range, current draw maxed out at 45 amps,
                60 F.
                > 11.04
                > 7.71
                > 4.5
                > 8.93
                > 8.79
                > 11.38
                > 11.49
                > 11.48
                > 11.43
                > 11.48
                > 11.22
                > 11.42
                >
                > Note that four of the five batteries in the front box are about
                dead.? I assume
                > that a number of cells in each of the four are dead.? Even 15,000
                miles earlier, battery #3 was always 0.1 volt lower than the highest
                on the pack.? This was probably an indication that it would be the
                first to die.
                >
                > I plan to change out the entire pack with new MK 8G27's.? I believe
                I got my money's worth out of these.? Being a real tightwad, I can
                still get a 10+ mile range between outlets.? I plan to do this during
                the next month while I wait for new batteries to arrive.
                >
                > Any comments?
                >
                > Sincerely,
                > Gary Carlson
                > ID License:? AMPEATR
                > 1992 Solectria Force
                >
                >
                >
                >
                > __________________________________________________________
                > More new features than ever. Check out the new AOL Mail ! -
                http://webmail.aol.com
                >
                >
                > [Non-text portions of this message have been removed]
                >





                ________________________________________________________________________
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                [Non-text portions of this message have been removed]
              • jim donovan
                Cold batteries will reduce range, but lessening the voltage to that extent sounds odd. I remember reading about your AC and how that heat can create a
                Message 7 of 21 , Feb 17, 2008
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                  Cold batteries will reduce range, but lessening the voltage to that extent sounds odd. I remember reading about your AC and how that heat can create a problem. I would not think that the problem would exist when the temp is so low. You do have a unique problem. It could just be an old pack. How old and how many miles on it?

                  As for me, I bought the car 2 years ago with 35,000 miles and just turned 50,000. Same pack except for the two replacements. I do not use an equalizer system either. I would not be surprised if they are the original pack.

                  Jim

                  BTW - I swearer by the thermal management


                  "Gerard (Gary) Carlson " <gjc0@...> wrote:

                  Jim:

                  No, I do not have any battery heaters in either the front or rear battery boxes.? I am wondering if I have the opposite problem that you did.? You said that your front batteries got too hot.? I am wondering if my front batteries got too cold in the Boise winters (typically 20 to 30 degrees F).? Lead-acid batteries are at their best at 80 degrees F.? I wonder if there was a temperature mismatch between the front and rear boxes.? The front batteries would be colder than the rear and become more deeply discharged.? During charging, they would be slightly undercharged because the charger's temperature probe is located in the rear box.

                  I am considering adding a little insulation to the front box IF I can fit it.? After getting 30,000 miles, I am wondering if the expense of battery heaters is really worth it.? I also have no battery equalization system like PakTrack.

                  Jim:? How many miles were you able to get from your battery pack?

                  Sincerely
                  Gary?Carlson
                  1992 Solectria Force
                  ID License:? AMPEATR
                  gjc0@...

                  -----Original Message-----
                  From: jim donovan <donovan66205@...>
                  To: solectria_ev@yahoogroups.com
                  Sent: Sun, 17 Feb 2008 6:28 am
                  Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements

                  Gary:

                  You are having much the same volt reading I had last year at this time. Do you use/have the battery thermal management system to warm the batteries? After doing some work last year, I found out that my front battery box heater was designed to get too hot and basically boiled the batteries. In working with an electronics store I found that the "thermostat" in the little black box was the wrong one (it allowed the box to get too warm). I replaced it with the next size down and replaced the two center batteries (OK - a different conversation here - replaced two out of 13 batteries is not good but was a better "test" of my theories that the expense warranted) and have put 10,000 miles on the pack since then. My "test" worked. I confirm battery box temperatures with an indoor/outdoor AAA battery loaded thermometer and have the outside wired lead in each of the battery boxed. Temperature dropped from ~140 to ~90. The batteries seem to work much better.

                  Jim
                  Westwood, KS

                  "Gerard (Gary) Carlson " <gjc0@...> wrote:
                  Greetings all:

                  I measured the voltages of my?twelve MK 8G27 Gels.
                  The pack is about four years old and has about 30,000 miles on it.

                  The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
                  batteries 6 to 12 are in back.? It appears that the front battery box
                  is a rough neighborhood.? I had an assistant record the battery voltages
                  for the draw test while I drove and used the economy knob to limit
                  the current to 100 amps. The battery voltages are listed in order starting
                  with battery number 1.

                  Voltage after full charge, no load,?sitting overnight at about 60 degrees? F.
                  13.24
                  13.22
                  13.14
                  13.26
                  13.24
                  13.26
                  13.23
                  13.20
                  13.20
                  13.22
                  13.29
                  13.22

                  Voltage after full charge with 100 amp draw at about 60 degrees F.
                  11.74
                  11.71
                  11.68
                  11.85
                  11.80
                  11.81
                  11.80
                  11.83
                  11.79
                  11.79
                  11.77
                  11.74

                  Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.
                  11.04
                  7.71
                  4.5
                  8.93
                  8.79
                  11.38
                  11.49
                  11.48
                  11.43
                  11.48
                  11.22
                  11.42

                  Note that four of the five batteries in the front box are about dead.? I assume
                  that a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.

                  I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.

                  Any comments?

                  Sincerely,
                  Gary Carlson
                  ID License:? AMPEATR
                  1992 Solectria Force

                  __________________________________________________________
                  More new features than ever. Check out the new AOL Mail ! - http://webmail.aol.com

                  [Non-text portions of this message have been removed]

                  ---------------------------------
                  Looking for last minute shopping deals? Find them fast with Yahoo! Search.

                  [Non-text portions of this message have been removed]

                  __________________________________________________________
                  More new features than ever. Check out the new AOL Mail ! - http://webmail.aol.com

                  [Non-text portions of this message have been removed]






                  ---------------------------------
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                  [Non-text portions of this message have been removed]
                • Gerard (Gary) Carlson
                  Jim Donovan: The twelve 8G27 MK batteries were purchased in December of 2002, so they are five years old.? They have about 30,000 miles on them. Looking at the
                  Message 8 of 21 , Feb 17, 2008
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                    Jim Donovan:



                    The twelve 8G27 MK batteries were purchased in December of 2002, so they are five years old.? They have about 30,000 miles on them.

                    Looking at the MK battery website:? www.mkbattery.com
                    In particular see page 10 of the technical manual at http://www.mkbattery.com/images/VRLA_TechManual.pdf

                    They give the following figures:? (first two columns only)
                    Depth of Discharge? Cycle Life?? Amp Hours?? Total Miles? Range/Cycle
                    100%??????????????????? 450?????????? 80??????????????? 25,200????? 56
                    80?%???????????????????? 600?????????? 64??????????????? 26,880??????44.8
                    50%??????????????????? 1000?????????? 40??????????????? 28,000??????28?????
                    25%??????????????????? 2100?????????? 20??????????????? 29,400????? 14
                    10%??????????????????? 5700?????????? 8??????????????????31,920?????? 5.6

                    I filled in the last three columns of the table above.? My vehicle gets about 0.7 miles per amp-hour with the 144 volt pack.? I multiplied the cycles in column 2 by the amp-hours in column 3 by 0.7 miles/amp-hour to get the total miles in column 4.? Column 5 is obtained by multiplying the amp-hours in column 3 by 0.7 miles/amp-hour to get range/cycle.

                    Since my average trip was about 10 miles, I think I got my money's worth.? Your figure of 50,000 miles is terrific.? Good job.??My figures are of course rough estimates, but they come close to my actual experience.? This is a good place to add the disclaimer:? Your mileage may vary.? Taxes and dealer destination charge ... blah ... blah ;-)

                    Sincerely,

                    Gary?Carlson
                    208-362-4999

                    -----Original Message-----
                    From: jim donovan <donovan66205@...>
                    To: solectria_ev@yahoogroups.com
                    Sent: Sun, 17 Feb 2008 5:30 pm
                    Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements







                    Cold batteries will reduce range, but lessening the voltage to that extent sounds odd. I remember reading about your AC and how that heat can create a problem. I would not think that the problem would exist when the temp is so low. You do have a unique problem. It could just be an old pack. How old and how many miles on it?

                    As for me, I bought the car 2 years ago with 35,000 miles and just turned 50,000. Same pack except for the two replacements. I do not use an equalizer system either. I would not be surprised if they are the original pack.

                    Jim

                    BTW - I swearer by the thermal management


                    "Gerard (Gary) Carlson " <gjc0@...> wrote:

                    Jim:

                    No, I do not have any battery heaters in either the front or rear battery boxes.? I am wondering if I have the opposite problem that you did.? You said that your front batteries got too hot.? I am wondering if my front batteries got too cold in the Boise winters (typically 20 to 30 degrees F).? Lead-acid batteries are at their best at 80 degrees F.? I wonder if there was a temperature mismatch between the front and rear boxes.? The front batteries would be colder than the rear and become more deeply discharged.? During charging, they would be slightly undercharged because the charger's temperature probe is located in the rear box.

                    I am considering adding a little insulation to the front box IF I can fit it.? After getting 30,000 miles, I am wondering if the expense of battery heaters is really worth it.? I also have no battery equalization system like PakTrack.

                    Jim:? How many miles were you able to get from your battery pack?

                    Sincerely
                    Gary?Carlson
                    1992 Solectria Force
                    ID License:? AMPEATR
                    gjc0@...

                    -----Original Message-----
                    From: jim donovan <donovan66205@...>
                    To: solectria_ev@yahoogroups.com
                    Sent: Sun, 17 Feb 2008 6:28 am
                    Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements

                    Gary:

                    You are having much the same volt reading I had last year at this time. Do you use/have the battery thermal management system to warm the batteries? After doing some work last year, I found out that my front battery box heater was designed to get too hot and basically boiled the batteries. In working with an electronics store I found that the "thermostat" in the little black box was the wrong one (it allowed the box to get too warm). I replaced it with the next size down and replaced the two center batteries (OK - a different conversation here - replaced two out of 13 batteries is not good but was a better "test" of my theories that the expense warranted) and have put 10,000 miles on the pack since then. My "test" worked. I confirm battery box temperatures with an indoor/outdoor AAA battery loaded thermometer and have the outside wired lead in each of the battery boxed. Temperature dropped from ~140 to ~90. The batteries seem to work much better.

                    Jim
                    Westwood, KS

                    "Gerard (Gary) Carlson " <gjc0@...> wrote:
                    Greetings all:

                    I measured the voltages of my?twelve MK 8G27 Gels.
                    The pack is about four years old and has about 30,000 miles on it.

                    The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
                    batteries 6 to 12 are in back.? It appears that the front battery box
                    is a rough neighborhood.? I had an assistant record the battery voltages
                    for the draw test while I drove and used the economy knob to limit
                    the current to 100 amps. The battery voltages are listed in order starting
                    with battery number 1.

                    Voltage after full charge, no load,?sitting overnight at about 60 degrees? F.
                    13.24
                    13.22
                    13.14
                    13.26
                    13.24
                    13.26
                    13.23
                    13.20
                    13.20
                    13.22
                    13.29
                    13.22

                    Voltage after full charge with 100 amp draw at about 60 degrees F.
                    11.74
                    11.71
                    11.68
                    11.85
                    11.80
                    11.81
                    11.80
                    11.83
                    11.79
                    11.79
                    11.77
                    11.74

                    Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.
                    11.04
                    7.71
                    4.5
                    8.93
                    8.79
                    11.38
                    11.49
                    11.48
                    11.43
                    11.48
                    11.22
                    11.42

                    Note that four of the five batteries in the front box are about dead.? I assume
                    that a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.

                    I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.

                    Any comments?

                    Sincerely,
                    Gary Carlson
                    ID License:? AMPEATR
                    1992 Solectria Force

                    __________________________________________________________
                    More new features than ever. Check out the new AOL Mail ! - http://webmail.aol.com

                    [Non-text portions of this message have been removed]

                    ---------------------------------
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                    [Non-text portions of this message have been removed]

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                  • Jay Grossman
                    Gary: What is your method for calculating depth of discharge? Jay H Grossman ... From: Gerard (Gary) Carlson To: solectria_ev@yahoogroups.com
                    Message 9 of 21 , Feb 18, 2008
                    View Source
                    • 0 Attachment
                      Gary:
                      What is your method for calculating depth of discharge?
                      Jay H Grossman


                      ----- Original Message ----
                      From: Gerard (Gary) Carlson <gjc0@...>
                      To: solectria_ev@yahoogroups.com
                      Sent: Monday, February 18, 2008 12:48:21 AM
                      Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements


                      Jim Donovan:

                      The twelve 8G27 MK batteries were purchased in December of 2002, so they are five years old.? They have about 30,000 miles on them.

                      Looking at the MK battery website:? www.mkbattery. com
                      In particular see page 10 of the technical manual at http://www.mkbatter y.com/images/ VRLA_TechManual. pdf

                      They give the following figures:? (first two columns only)
                      Depth of Discharge? Cycle Life?? Amp Hours?? Total Miles? Range/Cycle
                      100%???????? ????????? ?? 450????????? ? 80?????????? ????? 25,200????? 56
                      80?%???????? ????????? ??? 600????????? ? 64?????????? ????? 26,880?????? 44.8
                      50%????????? ????????? ? 1000???????? ?? 40?????????? ????? 28,000?????? 28?????
                      25%????????? ????????? ? 2100???????? ?? 20?????????? ????? 29,400????? 14
                      10%????????? ????????? ? 5700???????? ?? 8??????????? ???????31, 920?????? 5.6

                      I filled in the last three columns of the table above.? My vehicle gets about 0.7 miles per amp-hour with the 144 volt pack.? I multiplied the cycles in column 2 by the amp-hours in column 3 by 0.7 miles/amp-hour to get the total miles in column 4.? Column 5 is obtained by multiplying the amp-hours in column 3 by 0.7 miles/amp-hour to get range/cycle.

                      Since my average trip was about 10 miles, I think I got my money's worth.? Your figure of 50,000 miles is terrific.? Good job.??My figures are of course rough estimates, but they come close to my actual experience.? This is a good place to add the disclaimer:? Your mileage may vary.? Taxes and dealer destination charge ... blah ... blah ;-)

                      Sincerely,

                      Gary?Carlson
                      208-362-4999

                      -----Original Message-----
                      From: jim donovan <donovan66205@ yahoo.com>
                      To: solectria_ev@ yahoogroups. com
                      Sent: Sun, 17 Feb 2008 5:30 pm
                      Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements

                      Cold batteries will reduce range, but lessening the voltage to that extent sounds odd. I remember reading about your AC and how that heat can create a problem. I would not think that the problem would exist when the temp is so low. You do have a unique problem. It could just be an old pack. How old and how many miles on it?

                      As for me, I bought the car 2 years ago with 35,000 miles and just turned 50,000. Same pack except for the two replacements. I do not use an equalizer system either. I would not be surprised if they are the original pack.

                      Jim

                      BTW - I swearer by the thermal management

                      "Gerard (Gary) Carlson " <gjc0@...> wrote:

                      Jim:

                      No, I do not have any battery heaters in either the front or rear battery boxes.? I am wondering if I have the opposite problem that you did.? You said that your front batteries got too hot.? I am wondering if my front batteries got too cold in the Boise winters (typically 20 to 30 degrees F).? Lead-acid batteries are at their best at 80 degrees F.? I wonder if there was a temperature mismatch between the front and rear boxes.? The front batteries would be colder than the rear and become more deeply discharged.? During charging, they would be slightly undercharged because the charger's temperature probe is located in the rear box.

                      I am considering adding a little insulation to the front box IF I can fit it.? After getting 30,000 miles, I am wondering if the expense of battery heaters is really worth it.? I also have no battery equalization system like PakTrack.

                      Jim:? How many miles were you able to get from your battery pack?

                      Sincerely
                      Gary?Carlson
                      1992 Solectria Force
                      ID License:? AMPEATR
                      gjc0@...

                      -----Original Message-----
                      From: jim donovan <donovan66205@ yahoo.com>
                      To: solectria_ev@ yahoogroups. com
                      Sent: Sun, 17 Feb 2008 6:28 am
                      Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements

                      Gary:

                      You are having much the same volt reading I had last year at this time. Do you use/have the battery thermal management system to warm the batteries? After doing some work last year, I found out that my front battery box heater was designed to get too hot and basically boiled the batteries. In working with an electronics store I found that the "thermostat" in the little black box was the wrong one (it allowed the box to get too warm). I replaced it with the next size down and replaced the two center batteries (OK - a different conversation here - replaced two out of 13 batteries is not good but was a better "test" of my theories that the expense warranted) and have put 10,000 miles on the pack since then. My "test" worked. I confirm battery box temperatures with an indoor/outdoor AAA battery loaded thermometer and have the outside wired lead in each of the battery boxed. Temperature dropped from ~140 to ~90. The batteries seem to work much better.

                      Jim
                      Westwood, KS

                      "Gerard (Gary) Carlson " <gjc0@...> wrote:
                      Greetings all:

                      I measured the voltages of my?twelve MK 8G27 Gels.
                      The pack is about four years old and has about 30,000 miles on it.

                      The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
                      batteries 6 to 12 are in back.? It appears that the front battery box
                      is a rough neighborhood. ? I had an assistant record the battery voltages
                      for the draw test while I drove and used the economy knob to limit
                      the current to 100 amps. The battery voltages are listed in order starting
                      with battery number 1.

                      Voltage after full charge, no load,?sitting overnight at about 60 degrees? F.
                      13.24
                      13.22
                      13.14
                      13.26
                      13.24
                      13.26
                      13.23
                      13.20
                      13.20
                      13.22
                      13.29
                      13.22

                      Voltage after full charge with 100 amp draw at about 60 degrees F.
                      11.74
                      11.71
                      11.68
                      11.85
                      11.80
                      11.81
                      11.80
                      11.83
                      11.79
                      11.79
                      11.77
                      11.74

                      Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.
                      11.04
                      7.71
                      4.5
                      8.93
                      8.79
                      11.38
                      11.49
                      11.48
                      11.43
                      11.48
                      11.22
                      11.42

                      Note that four of the five batteries in the front box are about dead.? I assume
                      that a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.

                      I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.

                      Any comments?

                      Sincerely,
                      Gary Carlson
                      ID License:? AMPEATR
                      1992 Solectria Force

                      ____________ _________ _________ _________ _________ _________ _
                      More new features than ever. Check out the new AOL Mail ! - http://webmail. aol.com

                      [Non-text portions of this message have been removed]

                      ------------ --------- --------- ---
                      Looking for last minute shopping deals? Find them fast with Yahoo! Search.

                      [Non-text portions of this message have been removed]

                      ____________ _________ _________ _________ _________ _________ _
                      More new features than ever. Check out the new AOL Mail ! - http://webmail. aol.com

                      [Non-text portions of this message have been removed]

                      ------------ --------- --------- ---
                      Looking for last minute shopping deals? Find them fast with Yahoo! Search.

                      [Non-text portions of this message have been removed]

                      ____________ _________ _________ _________ _________ _________ _
                      More new features than ever. Check out the new AOL Mail ! - http://webmail. aol.com

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                      ____________________________________________________________________________________
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                      [Non-text portions of this message have been removed]
                    • Gerard (Gary) Carlson
                      Jay Grossman: May last email which had the table of expected life cycles vs depth of discharge per cycle was taken from the MK battery site technical reference
                      Message 10 of 21 , Feb 18, 2008
                      View Source
                      • 0 Attachment
                        Jay Grossman:



                        May last email which had the table of expected life cycles vs depth of discharge per cycle was taken from the MK battery site technical reference manual.



                        In my vehicle I have an E-meter which reads out volts, amps, KWH, and State of Charge (100% is fully charged).? Given the declining state of the batteries, the State of Charge as indicated on the E-meter is no longer reliable.? The E-meter thinks that the battery pack is an 80 amp-hour pack, but some of the batteries are only able to supply about 20 amp-hours before they are completely dead.

                        BTW:? When I look at my emails after they are filtered through the Yahoo Groups, the spaces in the text get turned into question marks "?".? I am doing something wrong?? Do other people see question marks embedded in my text?

                        Sincerely,
                        Gary?Carlson



                        -----Original Message-----
                        From: Jay Grossman <jgrossm3@...>
                        To: solectria_ev@yahoogroups.com
                        Sent: Mon, 18 Feb 2008 6:32 am
                        Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements






                        Gary:
                        What is your method for calculating depth of discharge?
                        Jay H Grossman

                        ----- Original Message ----
                        From: Gerard (Gary) Carlson <gjc0@...>
                        To: solectria_ev@yahoogroups.com
                        Sent: Monday, February 18, 2008 12:48:21 AM
                        Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements

                        Jim Donovan:

                        The twelve 8G27 MK batteries were purchased in December of 2002, so they are five years old.? They have about 30,000 miles on them.

                        Looking at the MK battery website:? www.mkbattery. com
                        In particular see page 10 of the technical manual at http://www.mkbatter y.com/images/ VRLA_TechManual. pdf

                        They give the following figures:? (first two columns only)
                        Depth of Discharge? Cycle Life?? Amp Hours?? Total Miles? Range/Cycle
                        100%???????? ????????? ?? 450????????? ? 80?????????? ????? 25,200????? 56
                        80?%???????? ????????? ??? 600????????? ? 64?????????? ????? 26,880?????? 44.8
                        50%????????? ????????? ? 1000???????? ?? 40?????????? ????? 28,000?????? 28?????
                        25%????????? ????????? ? 2100???????? ?? 20?????????? ????? 29,400????? 14
                        10%????????? ????????? ? 5700???????? ?? 8??????????? ???????31, 920?????? 5.6

                        I filled in the last three columns of the table above.? My vehicle gets about 0.7 miles per amp-hour with the 144 volt pack.? I multiplied the cycles in column 2 by the amp-hours in column 3 by 0.7 miles/amp-hour to get the total miles in column 4.? Column 5 is obtained by multiplying the amp-hours in column 3 by 0.7 miles/amp-hour to get range/cycle.

                        Since my average trip was about 10 miles, I think I got my money's worth.? Your figure of 50,000 miles is terrific.? Good job.??My figures are of course rough estimates, but they come close to my actual experience.? This is a good place to add the disclaimer:? Your mileage may vary.? Taxes and dealer destination charge ... blah ... blah ;-)

                        Sincerely,

                        Gary?Carlson
                        208-362-4999

                        -----Original Message-----
                        From: jim donovan <donovan66205@ yahoo.com>
                        To: solectria_ev@ yahoogroups. com
                        Sent: Sun, 17 Feb 2008 5:30 pm
                        Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements

                        Cold batteries will reduce range, but lessening the voltage to that extent sounds odd. I remember reading about your AC and how that heat can create a problem. I would not think that the problem would exist when the temp is so low. You do have a unique problem. It could just be an old pack. How old and how many miles on it?

                        As for me, I bought the car 2 years ago with 35,000 miles and just turned 50,000. Same pack except for the two replacements. I do not use an equalizer system either. I would not be surprised if they are the original pack.

                        Jim

                        BTW - I swearer by the thermal management

                        "Gerard (Gary) Carlson " <gjc0@...> wrote:

                        Jim:

                        No, I do not have any battery heaters in either the front or rear battery boxes.? I am wondering if I have the opposite problem that you did.? You said that your front batteries got too hot.? I am wondering if my front batteries got too cold in the Boise winters (typically 20 to 30 degrees F).? Lead-acid batteries are at their best at 80 degrees F.? I wonder if there was a temperature mismatch between the front and rear boxes.? The front batteries would be colder than the rear and become more deeply discharged.? During charging, they would be slightly undercharged because the charger's temperature probe is located in the rear box.

                        I am considering adding a little insulation to the front box IF I can fit it.? After getting 30,000 miles, I am wondering if the expense of battery heaters is really worth it.? I also have no battery equalization system like PakTrack.

                        Jim:? How many miles were you able to get from your battery pack?

                        Sincerely
                        Gary?Carlson
                        1992 Solectria Force
                        ID License:? AMPEATR
                        gjc0@...

                        -----Original Message-----
                        From: jim donovan <donovan66205@ yahoo.com>
                        To: solectria_ev@ yahoogroups. com
                        Sent: Sun, 17 Feb 2008 6:28 am
                        Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements

                        Gary:

                        You are having much the same volt reading I had last year at this time. Do you use/have the battery thermal management system to warm the batteries? After doing some work last year, I found out that my front battery box heater was designed to get too hot and basically boiled the batteries. In working with an electronics store I found that the "thermostat" in the little black box was the wrong one (it allowed the box to get too warm). I replaced it with the next size down and replaced the two center batteries (OK - a different conversation here - replaced two out of 13 batteries is not good but was a better "test" of my theories that the expense warranted) and have put 10,000 miles on the pack since then. My "test" worked. I confirm battery box temperatures with an indoor/outdoor AAA battery loaded thermometer and have the outside wired lead in each of the battery boxed. Temperature dropped from ~140 to ~90. The batteries seem to work much better.

                        Jim
                        Westwood, KS

                        "Gerard (Gary) Carlson " <gjc0@...> wrote:
                        Greetings all:

                        I measured the voltages of my?twelve MK 8G27 Gels.
                        The pack is about four years old and has about 30,000 miles on it.

                        The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and
                        batteries 6 to 12 are in back.? It appears that the front battery box
                        is a rough neighborhood. ? I had an assistant record the battery voltages
                        for the draw test while I drove and used the economy knob to limit
                        the current to 100 amps. The battery voltages are listed in order starting
                        with battery number 1.

                        Voltage after full charge, no load,?sitting overnight at about 60 degrees? F.
                        13.24
                        13.22
                        13.14
                        13.26
                        13.24
                        13.26
                        13.23
                        13.20
                        13.20
                        13.22
                        13.29
                        13.22

                        Voltage after full charge with 100 amp draw at about 60 degrees F.
                        11.74
                        11.71
                        11.68
                        11.85
                        11.80
                        11.81
                        11.80
                        11.83
                        11.79
                        11.79
                        11.77
                        11.74

                        Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.
                        11.04
                        7.71
                        4.5
                        8.93
                        8.79
                        11.38
                        11.49
                        11.48
                        11.43
                        11.48
                        11.22
                        11.42

                        Note that four of the five batteries in the front box are about dead.? I assume
                        that a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.

                        I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.

                        Any comments?

                        Sincerely,
                        Gary Carlson
                        ID License:? AMPEATR
                        1992 Solectria Force

                        ____________ _________ _________ _________ _________ _________ _
                        More new features than ever. Check out the new AOL Mail ! - http://webmail. aol.com

                        [Non-text portions of this message have been removed]

                        ------------ --------- --------- ---
                        Looking for last minute shopping deals? Find them fast with Yahoo! Search.

                        [Non-text portions of this message have been removed]

                        ____________ _________ _________ _________ _________ _________ _
                        More new features than ever. Check out the new AOL Mail ! - http://webmail. aol.com

                        [Non-text portions of this message have been removed]

                        ------------ --------- --------- ---
                        Looking for last minute shopping deals? Find them fast with Yahoo! Search.

                        [Non-text portions of this message have been removed]

                        ____________ _________ _________ _________ _________ _________ _
                        More new features than ever. Check out the new AOL Mail ! - http://webmail. aol.com

                        [Non-text portions of this message have been removed]

                        __________________________________________________________
                        Be a better friend, newshound, and
                        know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

                        [Non-text portions of this message have been removed]





                        ________________________________________________________________________
                        More new features than ever. Check out the new AOL Mail ! - http://webmail.aol.com


                        [Non-text portions of this message have been removed]
                      • Peter Fletcher
                        Yes I do See Question marks. Fletch. all over. To: solectria_ev@yahoogroups.comFrom: gjc0@aol.comDate: Mon, 18 Feb 2008 13:29:24 -0500Subject: Re:
                        Message 11 of 21 , Feb 19, 2008
                        View Source
                        • 0 Attachment
                          Yes I do See Question marks. Fletch. all over.


                          To: solectria_ev@yahoogroups.comFrom: gjc0@...: Mon, 18 Feb 2008 13:29:24 -0500Subject: Re: [solectria_ev] MK 8G27 Gel Battery Measurements




                          Jay Grossman:May last email which had the table of expected life cycles vs depth of discharge per cycle was taken from the MK battery site technical reference manual.In my vehicle I have an E-meter which reads out volts, amps, KWH, and State of Charge (100% is fully charged).? Given the declining state of the batteries, the State of Charge as indicated on the E-meter is no longer reliable.? The E-meter thinks that the battery pack is an 80 amp-hour pack, but some of the batteries are only able to supply about 20 amp-hours before they are completely dead.BTW:? When I look at my emails after they are filtered through the Yahoo Groups, the spaces in the text get turned into question marks "?".? I am doing something wrong?? Do other people see question marks embedded in my text?Sincerely,Gary?Carlson-----Original Message-----From: Jay Grossman <jgrossm3@...>To: solectria_ev@yahoogroups.comSent: Mon, 18 Feb 2008 6:32 amSubject: Re: [solectria_ev] MK 8G27 Gel Battery MeasurementsGary:What is your method for calculating depth of discharge?Jay H Grossman----- Original Message ----From: Gerard (Gary) Carlson <gjc0@...>To: solectria_ev@yahoogroups.comSent: Monday, February 18, 2008 12:48:21 AMSubject: Re: [solectria_ev] MK 8G27 Gel Battery MeasurementsJim Donovan:The twelve 8G27 MK batteries were purchased in December of 2002, so they are five years old.? They have about 30,000 miles on them.Looking at the MK battery website:? www.mkbattery. com In particular see page 10 of the technical manual at http://www.mkbatter y.com/images/ VRLA_TechManual. pdfThey give the following figures:? (first two columns only)Depth of Discharge? Cycle Life?? Amp Hours?? Total Miles? Range/Cycle100%???????? ????????? ?? 450????????? ? 80?????????? ????? 25,200????? 5680?%???????? ????????? ??? 600????????? ? 64?????????? ????? 26,880?????? 44.850%????????? ????????? ? 1000???????? ?? 40?????????? ????? 28,000?????? 28????? 25%????????? ????????? ? 2100???????? ?? 20?????????? ????? 29,400????? 1410%????????? ????????? ? 5700???????? ?? 8??????????? ???????31, 920?????? 5.6I filled in the last three columns of the table above.? My vehicle gets about 0.7 miles per amp-hour with the 144 volt pack.? I multiplied the cycles in column 2 by the amp-hours in column 3 by 0.7 miles/amp-hour to get the total miles in column 4.? Column 5 is obtained by multiplying the amp-hours in column 3 by 0.7 miles/amp-hour to get range/cycle.Since my average trip was about 10 miles, I think I got my money's worth.? Your figure of 50,000 miles is terrific.? Good job.??My figures are of course rough estimates, but they come close to my actual experience.? This is a good place to add the disclaimer:? Your mileage may vary.? Taxes and dealer destination charge ... blah ... blah ;-)Sincerely,Gary?Carlson208-362-4999-----Original Message-----From: jim donovan <donovan66205@ yahoo.com>To: solectria_ev@ yahoogroups. comSent: Sun, 17 Feb 2008 5:30 pmSubject: Re: [solectria_ev] MK 8G27 Gel Battery MeasurementsCold batteries will reduce range, but lessening the voltage to that extent sounds odd. I remember reading about your AC and how that heat can create a problem. I would not think that the problem would exist when the temp is so low. You do have a unique problem. It could just be an old pack. How old and how many miles on it?As for me, I bought the car 2 years ago with 35,000 miles and just turned 50,000. Same pack except for the two replacements. I do not use an equalizer system either. I would not be surprised if they are the original pack.JimBTW - I swearer by the thermal management"Gerard (Gary) Carlson " <gjc0@...> wrote:Jim:No, I do not have any battery heaters in either the front or rear battery boxes.? I am wondering if I have the opposite problem that you did.? You said that your front batteries got too hot.? I am wondering if my front batteries got too cold in the Boise winters (typically 20 to 30 degrees F).? Lead-acid batteries are at their best at 80 degrees F.? I wonder if there was a temperature mismatch between the front and rear boxes.? The front batteries would be colder than the rear and become more deeply discharged.? During charging, they would be slightly undercharged because the charger's temperature probe is located in the rear box.I am considering adding a little insulation to the front box IF I can fit it.? After getting 30,000 miles, I am wondering if the expense of battery heaters is really worth it.? I also have no battery equalization system like PakTrack.Jim:? How many miles were you able to get from your battery pack?SincerelyGary?Carlson1992 Solectria ForceID License:? AMPEATRgjc0@... -----Original Message-----From: jim donovan <donovan66205@ yahoo.com>To: solectria_ev@ yahoogroups. comSent: Sun, 17 Feb 2008 6:28 amSubject: Re: [solectria_ev] MK 8G27 Gel Battery MeasurementsGary:You are having much the same volt reading I had last year at this time. Do you use/have the battery thermal management system to warm the batteries? After doing some work last year, I found out that my front battery box heater was designed to get too hot and basically boiled the batteries. In working with an electronics store I found that the "thermostat" in the little black box was the wrong one (it allowed the box to get too warm). I replaced it with the next size down and replaced the two center batteries (OK - a different conversation here - replaced two out of 13 batteries is not good but was a better "test" of my theories that the expense warranted) and have put 10,000 miles on the pack since then. My "test" worked. I confirm battery box temperatures with an indoor/outdoor AAA battery loaded thermometer and have the outside wired lead in each of the battery boxed. Temperature dropped from ~140 to ~90. The batteries seem to work much better.JimWestwood, KS"Gerard (Gary) Carlson " <gjc0@...> wrote:Greetings all:I measured the voltages of my?twelve MK 8G27 Gels.The pack is about four years old and has about 30,000 miles on it.The batteries are numbered 1 to 12. Batteries 1 to 5 are in front and batteries 6 to 12 are in back.? It appears that the front battery boxis a rough neighborhood. ? I had an assistant record the battery voltagesfor the draw test while I drove and used the economy knob to limitthe current to 100 amps. The battery voltages are listed in order startingwith battery number 1.Voltage after full charge, no load,?sitting overnight at about 60 degrees? F. 13.2413.2213.1413.2613.2413.2613.2313.2013.2013.2213.2913.22Voltage after full charge with 100 amp draw at about 60 degrees F.11.7411.7111.6811.8511.8011.8111.8011.8311.7911.7911.7711.74Voltage after 15 miles of range, current draw maxed out at 45 amps, 60 F.11.047.714.58.938.7911.3811.4911.4811.4311.4811.2211.42Note that four of the five batteries in the front box are about dead.? I assumethat a number of cells in each of the four are dead.? Even 15,000 miles earlier, battery #3 was always 0.1 volt lower than the highest on the pack.? This was probably an indication that it would be the first to die.I plan to change out the entire pack with new MK 8G27's.? I believe I got my money's worth out of these.? Being a real tightwad, I can still get a 10+ mile range between outlets.? I plan to do this during the next month while I wait for new batteries to arrive.Any comments?Sincerely,Gary Carlson ID License:? AMPEATR1992 Solectria Force____________ _________ _________ _________ _________ _________ _More new features than ever. Check out the new AOL Mail ! - http://webmail. aol.com[Non-text portions of this message have been removed]------------ --------- --------- ---Looking for last minute shopping deals? Find them fast with Yahoo! Search.[Non-text portions of this message have been removed]____________ _________ _________ _________ _________ _________ _More new features than ever. Check out the new AOL Mail ! - http://webmail. aol.com[Non-text portions of this message have been removed]------------ --------- --------- ---Looking for last minute shopping deals? Find them fast with Yahoo! 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                        • jim donovan
                          Hey Gary: This is Jim Donovan again. I have contacted you recently and have followed your listings on the Solectria controller and reprogramming with great
                          Message 12 of 21 , Mar 9, 2008
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                            Hey Gary:

                            This is Jim Donovan again. I have contacted you recently and have followed your listings on the Solectria controller and reprogramming with great interest. I recently purchased the Houston EV Solectria and am making plans on going down to Houston to pick it up. I plan on trailering it back to the KCMO area from March 20 until I get home (probably two days).

                            Any way, I believe that you are in Oklahoma. How close to I-35 are you? Are you open minded to having a drive through stop off and see what you have done to your vehicle. The one I purchased has a blown controller and I plan on putting my current one in it to make it drivable. However, that still leaves me one controller short. I am trying to learn what my options are and I like what I understand you have done.

                            Well, are you open minded to s drive through show and tell?

                            Jim
                            Westwood, KS
                            913.236.9466




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