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Lithium voltage sag

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  • ldr214
    I still haven t put lithium s in the 97 Force. Partly as I can t decide what size AH cells to use. Forgetting somewhat the bigger is better mantra I was
    Message 1 of 14 , Dec 5, 2011
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      I still haven't put lithium's in the 97 Force. Partly as I can't decide what size AH cells to use. Forgetting somewhat the bigger is better mantra I was wondering what kind of voltage sag others are seeing on their lithium's in the ac powered Force or E10's.

      I really don't need a lot of range. Cells in the 60-100 AH range are all more than adequate for my wattage requirements. 52 60 or 70 AH cells seem to work on paper if the voltage sag isn't significant. Even 40 AH cells would cover my range needs but I think the sag might become a issue.

      Any real world information appreciated?

      Mike R
      97 Force
    • Dexion
      What range do you need? I ve got 100 ah cells and have no issues with sag. 200 amps sags the pack to 160v at 50% soc and 50F temp cells (52 cells) if I were to
      Message 2 of 14 , Dec 5, 2011
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        What range do you need? I've got 100 ah cells and have no issues with sag. 200 amps sags the pack to 160v at 50% soc and 50F temp cells (52 cells) if I were to do it again I would use 60's as I mostly drive in normal and only need 30 miles 2 times a day and can charge at work.

        On Dec 5, 2011, at 3:38 PM, "ldr214" <replytome@...> wrote:

        > I still haven't put lithium's in the 97 Force. Partly as I can't decide what size AH cells to use. Forgetting somewhat the bigger is better mantra I was wondering what kind of voltage sag others are seeing on their lithium's in the ac powered Force or E10's.
        >
        > I really don't need a lot of range. Cells in the 60-100 AH range are all more than adequate for my wattage requirements. 52 60 or 70 AH cells seem to work on paper if the voltage sag isn't significant. Even 40 AH cells would cover my range needs but I think the sag might become a issue.
        >
        > Any real world information appreciated?
        >
        > Mike R
        > 97 Force
        >
        >


        [Non-text portions of this message have been removed]
      • d. Bouton Baldridge
        Hi Mike, Since going on three years with my 48  40Ah cells in my 92 Force I can say that when the temperature is above 70 degrees there is no noticeable sag
        Message 3 of 14 , Dec 5, 2011
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          Hi Mike,
          Since going on three years with my 48  40Ah cells in my '92' Force I can say that when the temperature is above 70 degrees there is no noticeable sag especially with the loss of weight from the Pb. But since price was a major concern when I bought them, if I bought them today I'd probably go bigger just because of the termperature differential and the associated sag otherwise I don't really need the range either. So I would suggest you go with what you can afford.
          Bouty   


          ________________________________
          From: ldr214 <replytome@...>
          To: solectria_ev@yahoogroups.com
          Sent: Monday, December 5, 2011 3:38 PM
          Subject: [solectria_ev] Lithium voltage sag


           
          I still haven't put lithium's in the 97 Force. Partly as I can't decide what size AH cells to use. Forgetting somewhat the bigger is better mantra I was wondering what kind of voltage sag others are seeing on their lithium's in the ac powered Force or E10's.

          I really don't need a lot of range. Cells in the 60-100 AH range are all more than adequate for my wattage requirements. 52 60 or 70 AH cells seem to work on paper if the voltage sag isn't significant. Even 40 AH cells would cover my range needs but I think the sag might become a issue.

          Any real world information appreciated?

          Mike R
          97 Force




          [Non-text portions of this message have been removed]
        • Rick
          Mike, I am thinking about a lithium conversion for my 1996 force. It is a 156 volt system. Can you give me a ballpark on costs and range for your conversion?
          Message 4 of 14 , Dec 5, 2011
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            Mike, I am thinking about a lithium conversion for my 1996 force. It is a 156 volt system. Can you give me a ballpark on costs and range for your conversion? Real rough is fine.
            Thanks.


            Sent from my iPhone

            On Dec 5, 2011, at 4:09 PM, "d. Bouton Baldridge" <cfrkeepr@...> wrote:

            > Hi Mike,
            > Since going on three years with my 48 40Ah cells in my '92' Force I can say that when the temperature is above 70 degrees there is no noticeable sag especially with the loss of weight from the Pb. But since price was a major concern when I bought them, if I bought them today I'd probably go bigger just because of the termperature differential and the associated sag otherwise I don't really need the range either. So I would suggest you go with what you can afford.
            > Bouty
            >
            > ________________________________
            > From: ldr214 <replytome@...>
            > To: solectria_ev@yahoogroups.com
            > Sent: Monday, December 5, 2011 3:38 PM
            > Subject: [solectria_ev] Lithium voltage sag
            >
            >
            > I still haven't put lithium's in the 97 Force. Partly as I can't decide what size AH cells to use. Forgetting somewhat the bigger is better mantra I was wondering what kind of voltage sag others are seeing on their lithium's in the ac powered Force or E10's.
            >
            > I really don't need a lot of range. Cells in the 60-100 AH range are all more than adequate for my wattage requirements. 52 60 or 70 AH cells seem to work on paper if the voltage sag isn't significant. Even 40 AH cells would cover my range needs but I think the sag might become a issue.
            >
            > Any real world information appreciated?
            >
            > Mike R
            > 97 Force
            >
            > [Non-text portions of this message have been removed]
            >
            >


            [Non-text portions of this message have been removed]
          • Charles Bliss
            Below is an Excel work up I did for my conversion. The prices may have changed a little but I suspect they are close. One thing missing is the battery box
            Message 5 of 14 , Dec 5, 2011
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              Below is an Excel work up I did for my conversion. The prices may have changed a little but I suspect they are close. One thing missing is the battery box that drops in to keep the cells compressed. I am making that and already have the metal and hardware. This is what I have purchased.



              Physical

              49 Quan

              3.2 Nom Volts

              100 AH/cell

              191.1 Pack full charge (3.8 V)

              122.5 Pack empty (2.5 V)

              156.8 Nominal Pack Volts

              15.68 KWH

              71.27 Range @ 220wh/mi

              Battery

              Costs

              $107.50 Battery Price each

              $343.00 49 Straps @ $7

              $5,267.50 49 Batteries

              $480.66 Shipping Duty Port Fees @ 9.13%

              $6,091.16 Subtotal

              $546.08 Sales Tax, San Mateo, CA @ 9.50%

              $6,637.23 Battery Total



              BMS $325.00 BMS

              $612.50 49 BMS Modules

              $937.50 BMS Subtotal

              Project $89.06 Sales Tax, San Mateo, CA @ 9.50%

              $1,026.56 BMS Total

              $7,663.80 Total



              From: solectria_ev@yahoogroups.com [mailto:solectria_ev@yahoogroups.com] On Behalf Of Rick
              Sent: Monday, December 05, 2011 9:21 PM
              To: solectria_ev@yahoogroups.com
              Subject: Re: [solectria_ev] Lithium voltage sag





              Mike, I am thinking about a lithium conversion for my 1996 force. It is a 156 volt system. Can you give me a ballpark on costs and range for your conversion? Real rough is fine.
              Thanks.







              [Non-text portions of this message have been removed]
            • d. Bouton Baldridge
              Hi Rick I am guessing that you were including me; anyway a rough figure is $1.20/ Amphour, so if you decide what size cell, 40,60,...100 Amphour multiply $ 1.2
              Message 6 of 14 , Dec 6, 2011
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                Hi Rick
                I am guessing that you were including me; anyway a rough figure is $1.20/ Amphour, so if you decide what size cell, 40,60,...100 Amphour multiply $ 1.2 times the Amphour times the number of  cells which in your case would be 48 for a 160v pack. You could probably go higher than 48 cells if you wanted. Mine was a 144v pack and I went to 160v but my controller will not let me go any higher.
                Bouty


                ________________________________
                From: Rick <k1ykz7@...>
                To: "solectria_ev@yahoogroups.com" <solectria_ev@yahoogroups.com>
                Sent: Tuesday, December 6, 2011 12:20 AM
                Subject: Re: [solectria_ev] Lithium voltage sag


                 
                Mike, I am thinking about a lithium conversion for my 1996 force. It is a 156 volt system. Can you give me a ballpark on costs and range for your conversion? Real rough is fine.
                Thanks.

                Sent from my iPhone

                On Dec 5, 2011, at 4:09 PM, "d. Bouton Baldridge" <cfrkeepr@...> wrote:

                > Hi Mike,
                > Since going on three years with my 48 40Ah cells in my '92' Force I can say that when the temperature is above 70 degrees there is no noticeable sag especially with the loss of weight from the Pb. But since price was a major concern when I bought them, if I bought them today I'd probably go bigger just because of the termperature differential and the associated sag otherwise I don't really need the range either. So I would suggest you go with what you can afford.
                > Bouty
                >
                > ________________________________
                > From: ldr214 <replytome@...>
                > To: solectria_ev@yahoogroups.com
                > Sent: Monday, December 5, 2011 3:38 PM
                > Subject: [solectria_ev] Lithium voltage sag
                >
                >
                > I still haven't put lithium's in the 97 Force. Partly as I can't decide what size AH cells to use. Forgetting somewhat the bigger is better mantra I was wondering what kind of voltage sag others are seeing on their lithium's in the ac powered Force or E10's.
                >
                > I really don't need a lot of range. Cells in the 60-100 AH range are all more than adequate for my wattage requirements. 52 60 or 70 AH cells seem to work on paper if the voltage sag isn't significant. Even 40 AH cells would cover my range needs but I think the sag might become a issue.
                >
                > Any real world information appreciated?
                >
                > Mike R
                > 97 Force
                >
                > [Non-text portions of this message have been removed]
                >
                >

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




                [Non-text portions of this message have been removed]
              • ldr214
                Appreciate all the responses. To elaborate a little more. The range of the Pba s has been mostly adequate. When I need to go further than 25 miles is likely
                Message 7 of 14 , Dec 6, 2011
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                  Appreciate all the responses.

                  To elaborate a little more.

                  The range of the Pba's has been mostly adequate. When I need to go further than 25 miles is likely beyond a 100 mile range and all freeway so I take the gas vehicle for many reasons besides range. Normally the max distance need is under 30 miles and only a few times per month at most. A lot of 2 to 10 mile trips mostly. But I'm interested in the ability to maintain full power all the time if needed, for life of pack hopefully. Something the Pba's can't do. I drive almost exclusively in econ just to keep from beating up on the Pba cells. But it would be nice not to have it slow for slopes even in power mode.

                  A 40 AH CALB pack today cost the same locally as a new set of Deka gels $3K so that is almost no brainer. Bouty has the numbers for that end of the scale and I like what I see. His car is a bit lighter than the 4 door, so it is good to see Dexion's numbers as I'm leaning in the 70AH direction.

                  52 cells without any attachments in the CALB brand are at about $3K, 5K and 7K respectively for 40,70 and 100AH cells on today's market. For the most part bigger cells gives me just a lot more reserve and power potential (maybe longevity). Need changes aren't very likely. BMS and all that stuff costs essentially the same for all the sizes.

                  Hope to hear from a few more of the owners that have been running the 90 or 100's for awhile. Especially anyone who has some grades's to deal with. I don't think anyone has put in 60's or 70's.

                  The conversions out there that are DC have such high power requirements that they demand 100's and up.

                  Larger cell and high C rate A123 cost and availability still a mystery.


                  Mike R
                  97 Force

                  --- In solectria_ev@yahoogroups.com, Dexion <dexion111@...> wrote:
                  >
                  > What range do you need? I've got 100 ah cells and have no issues with sag. 200 amps sags the pack to 160v at 50% soc and 50F temp cells (52 cells) if I were to do it again I would use 60's as I mostly drive in normal and only need 30 miles 2 times a day and can charge at work.
                  >
                  > On Dec 5, 2011, at 3:38 PM, "ldr214" <replytome@...> wrote:
                  >
                  > > I still haven't put lithium's in the 97 Force. Partly as I can't decide what size AH cells to use. Forgetting somewhat the bigger is better mantra I was wondering what kind of voltage sag others are seeing on their lithium's in the ac powered Force or E10's.
                  > >
                  > > I really don't need a lot of range. Cells in the 60-100 AH range are all more than adequate for my wattage requirements. 52 60 or 70 AH cells seem to work on paper if the voltage sag isn't significant. Even 40 AH cells would cover my range needs but I think the sag might become a issue.
                  > >
                  > > Any real world information appreciated?
                  > >
                  > > Mike R
                  > > 97 Force
                  > >
                  > >
                  >
                  >
                  > [Non-text portions of this message have been removed]
                  >
                • d. Bouton Baldridge
                  Hi Mike, great interpretation. I would like to add that the Calbs have a pretty good reputation for providing better current for their size than the others
                  Message 8 of 14 , Dec 6, 2011
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                    Hi Mike, great interpretation. I would like to add that the Calbs have a pretty good reputation for providing better current for their size than the others although I have not used them this is what the DC users claim so it would seem that you might still get your power with the Calbs without the need to buy a larger pack. FWIW I also don't know if the temperature thing affects the Calbs like the TSs, but a waterbed heater seems to work for the TSs.
                     
                    Bouty


                    ________________________________
                    From: ldr214 <replytome@...>
                    To: solectria_ev@yahoogroups.com
                    Sent: Tuesday, December 6, 2011 11:29 AM
                    Subject: [solectria_ev] Re: Lithium voltage sag


                     


                    Appreciate all the responses.

                    To elaborate a little more.

                    The range of the Pba's has been mostly adequate. When I need to go further than 25 miles is likely beyond a 100 mile range and all freeway so I take the gas vehicle for many reasons besides range. Normally the max distance need is under 30 miles and only a few times per month at most. A lot of 2 to 10 mile trips mostly. But I'm interested in the ability to maintain full power all the time if needed, for life of pack hopefully. Something the Pba's can't do. I drive almost exclusively in econ just to keep from beating up on the Pba cells. But it would be nice not to have it slow for slopes even in power mode.

                    A 40 AH CALB pack today cost the same locally as a new set of Deka gels $3K so that is almost no brainer. Bouty has the numbers for that end of the scale and I like what I see. His car is a bit lighter than the 4 door, so it is good to see Dexion's numbers as I'm leaning in the 70AH direction.

                    52 cells without any attachments in the CALB brand are at about $3K, 5K and 7K respectively for 40,70 and 100AH cells on today's market. For the most part bigger cells gives me just a lot more reserve and power potential (maybe longevity). Need changes aren't very likely. BMS and all that stuff costs essentially the same for all the sizes.

                    Hope to hear from a few more of the owners that have been running the 90 or 100's for awhile. Especially anyone who has some grades's to deal with. I don't think anyone has put in 60's or 70's.

                    The conversions out there that are DC have such high power requirements that they demand 100's and up.

                    Larger cell and high C rate A123 cost and availability still a mystery.

                    Mike R
                    97 Force

                    --- In solectria_ev@yahoogroups.com, Dexion <dexion111@...> wrote:
                    >
                    > What range do you need? I've got 100 ah cells and have no issues with sag. 200 amps sags the pack to 160v at 50% soc and 50F temp cells (52 cells) if I were to do it again I would use 60's as I mostly drive in normal and only need 30 miles 2 times a day and can charge at work.
                    >
                    > On Dec 5, 2011, at 3:38 PM, "ldr214" <replytome@...> wrote:
                    >
                    > > I still haven't put lithium's in the 97 Force. Partly as I can't decide what size AH cells to use. Forgetting somewhat the bigger is better mantra I was wondering what kind of voltage sag others are seeing on their lithium's in the ac powered Force or E10's.
                    > >
                    > > I really don't need a lot of range. Cells in the 60-100 AH range are all more than adequate for my wattage requirements. 52 60 or 70 AH cells seem to work on paper if the voltage sag isn't significant. Even 40 AH cells would cover my range needs but I think the sag might become a issue.
                    > >
                    > > Any real world information appreciated?
                    > >
                    > > Mike R
                    > > 97 Force
                    > >
                    > >
                    >
                    >
                    > [Non-text portions of this message have been removed]
                    >




                    [Non-text portions of this message have been removed]
                  • Charles Bliss
                    The Calbs are designed to operate at a lower temperature (like in missiles) ... [Non-text portions of this message have been removed]
                    Message 9 of 14 , Dec 6, 2011
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                      The Calbs are designed to operate at a lower temperature (like in missiles)

                      On 12/6/2011 9:13 AM, d. Bouton Baldridge wrote:
                      >
                      > Hi Mike, great interpretation. I would like to add that the Calbs have
                      > a pretty good reputation for providing better current for their size
                      > than the others although I have not used them this is what the DC
                      > users claim so it would seem that you might still get your power with
                      > the Calbs without the need to buy a larger pack. FWIW I also don't
                      > know if the temperature thing affects the Calbs like the TSs, but a
                      > waterbed heater seems to work for the TSs.
                      >
                      >


                      [Non-text portions of this message have been removed]
                    • S
                      What is your source for 100AH lithium batteries for $107.50 apiece? I ve been looking at CALB, GBS and Thundersky which are running around $1.30/AH - so
                      Message 10 of 14 , Dec 6, 2011
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                        What is your source for 100AH lithium batteries for $107.50 apiece? I've been looking at CALB, GBS and Thundersky which are running around $1.30/AH - so $130.00/battery.

                        Thanks,
                        Sean
                        '99 Force

                        --- In solectria_ev@yahoogroups.com, "Charles Bliss" <cbliss@...> wrote:
                        >
                        > Below is an Excel work up I did for my conversion. The prices may have changed a little but I suspect they are close. One thing missing is the battery box that drops in to keep the cells compressed. I am making that and already have the metal and hardware. This is what I have purchased.
                        >
                        >
                        >
                        > Physical
                        >
                        > 49 Quan
                        >
                        > 3.2 Nom Volts
                        >
                        > 100 AH/cell
                        >
                        > 191.1 Pack full charge (3.8 V)
                        >
                        > 122.5 Pack empty (2.5 V)
                        >
                        > 156.8 Nominal Pack Volts
                        >
                        > 15.68 KWH
                        >
                        > 71.27 Range @ 220wh/mi
                        >
                        > Battery
                        >
                        > Costs
                        >
                        > $107.50 Battery Price each
                        >
                        > $343.00 49 Straps @ $7
                        >
                        > $5,267.50 49 Batteries
                        >
                        > $480.66 Shipping Duty Port Fees @ 9.13%
                        >
                        > $6,091.16 Subtotal
                        >
                        > $546.08 Sales Tax, San Mateo, CA @ 9.50%
                        >
                        > $6,637.23 Battery Total
                        >
                        >
                        >
                        > BMS $325.00 BMS
                        >
                        > $612.50 49 BMS Modules
                        >
                        > $937.50 BMS Subtotal
                        >
                        > Project $89.06 Sales Tax, San Mateo, CA @ 9.50%
                        >
                        > $1,026.56 BMS Total
                        >
                        > $7,663.80 Total
                        >
                        >
                        >
                        > From: solectria_ev@yahoogroups.com [mailto:solectria_ev@yahoogroups.com] On Behalf Of Rick
                        > Sent: Monday, December 05, 2011 9:21 PM
                        > To: solectria_ev@yahoogroups.com
                        > Subject: Re: [solectria_ev] Lithium voltage sag
                        >
                        >
                        >
                        >
                        >
                        > Mike, I am thinking about a lithium conversion for my 1996 force. It is a 156 volt system. Can you give me a ballpark on costs and range for your conversion? Real rough is fine.
                        > Thanks.
                        >
                        >
                        >
                        >
                        >
                        >
                        >
                        > [Non-text portions of this message have been removed]
                        >
                      • Charles Bliss
                        http://www.alliancerenewableenergy.com/100-Ah-TS-LFP100AHA.htm disclaimer: I work part time for them. Notice in my estimated price, that import duty, shipping
                        Message 11 of 14 , Dec 6, 2011
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                          http://www.alliancerenewableenergy.com/100-Ah-TS-LFP100AHA.htm

                          disclaimer: I work part time for them. Notice in my estimated price,
                          that import duty, shipping and taxes are extra.
                          I think I was a little high on the connections straps.

                          On 12/6/2011 11:11 AM, S wrote:
                          >
                          >
                          >
                          > What is your source for 100AH lithium batteries for $107.50 apiece?
                          > I've been looking at CALB, GBS and Thundersky which are running around
                          > $1.30/AH - so $130.00/battery.
                          >
                          > Thanks,
                          > Sean
                          > '99 Forceli:
                          >


                          [Non-text portions of this message have been removed]
                        • Wolf Packs, Inc.
                          ... I climb 2,600 feet in 17 miles to get home. The first half is 1% ~ 2% uphill grade (45~50 mph speed limit) and the last half is 6% ~ 7% (I keep it between
                          Message 12 of 14 , Dec 7, 2011
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                            > Hope to hear from a few more of the owners that have been running the 90 or 100's for awhile. Especially anyone who has some grades's to deal with.

                            I climb 2,600 feet in 17 miles to get home. The first half is 1% ~ 2% uphill grade (45~50 mph speed limit) and the last half is 6% ~ 7% (I keep it between 30 and 35 mph, like most gas cars) on a very curvy road. The Force uses 32 ~ 34 amp hours to get home. I always head home with a full charge. I use Normal mode because if I switch to Power mode I will quickly sag some cells to 2.6v or less. I set my lowest cell under voltage alarm at 2.704 volts and I can quickly trip that alarm in Normal mode if I floor it.

                            I had to go with Lithium because the fresh Lead pack I bought when I got the car kept going into limp mode on the last mile of the climb before getting home. I really like the Lithium pack. The car feels lighter in the turns, it easily cruises up the hill like a gas car without getting any cells below 2.8 volts. It's a lot more fun to drive without the extra 500+ pounds. Still, if I floor it on the freeway in Normal mode it would sag some cells lower than I want to go.



                            > This is my major concern with all conversions. I have a friend that put all his batteries in the bed of his S-10 and come the first rain he slid into the rear end of the car in front of him - not enough weight on the front axel.



                            I don't notice the front to rear weight issue when driving the curves in rain. When I hit the brakes to avoid deer, there are lots of them in these mountains, the front end drops and the car stops quickly. Perhaps the S-10 had other braking concerns like narrow or worn tires, extra weight behind the rear axle, low vacuum pressure, glazed pads, etc. I rarely drive the Force when it's snowing because of the heater draw while climbing toward home, but the few times I have it feels fine. I originally had 20 cells in the front box for weight on the front end. Last winter I changed to 8 cells in the front box and can not tell the difference. I would have all 48 in back if they would fit that way while being strapped into the 4 cell compressed bundles.

                            If I were to build another Force for my wife I'd probably put in 50 of the160Ah cells. She is not as careful as I am with the accelerator pedal (coming out of the steeper turns) and she has tripped the under voltage alarm a few times.

                            One suggestion for new converters: put the display where you can easily see it while driving. My display is on the cup holder below the radio and I have to look down to glance at it. I only take 1 to 2 seconds to see the voltages as they scroll to show high & low but I recently had a close call with a skunk when I looked up. In city driving it could be dangerous. It's like texting while driving� it's a bad idea.

                            Pictures at:

                            http://traildog.blogspot.com/

                            Paul Martin
                            Ashland, Oregon

                            1997 Force
                            48 TS 100Ah cells (now have 7,000 miles on them)
                            Hardy BMS-48
                            Zivan NG3

                            [Non-text portions of this message have been removed]
                          • ldr214
                            Paul very useful info. Are you still seeing the same volts as mention in the blog post on the TS pack when under load. I see you only used 48 cells and my
                            Message 13 of 14 , Dec 7, 2011
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                              Paul very useful info.
                              Are you still seeing the same volts as mention in the blog post on the TS pack when under load. I see you only used 48 cells and my plan is for 52. You said you would do 50 next time. Unless I messed up my math the CALB 100 should fit with a 52 count.

                              I'll likely never do a 2600 foot climbing grade but I'm impressed that you do it regularly. Do you leave plenty of charge space for a regen down the hill or fill it up at home?

                              Mike R
                              97 Force

                              --- In solectria_ev@yahoogroups.com, "Wolf Packs, Inc." <traildog@...> wrote:
                              >
                              > > Hope to hear from a few more of the owners that have been running the 90 or 100's for awhile. Especially anyone who has some grades's to deal with.
                              >
                              > I climb 2,600 feet in 17 miles to get home. The first half is 1% ~ 2% uphill grade (45~50 mph speed limit) and the last half is 6% ~ 7% (I keep it between 30 and 35 mph, like most gas cars) on a very curvy road. The Force uses 32 ~ 34 amp hours to get home. I always head home with a full charge. I use Normal mode because if I switch to Power mode I will quickly sag some cells to 2.6v or less. I set my lowest cell under voltage alarm at 2.704 volts and I can quickly trip that alarm in Normal mode if I floor it....... .......
                              > Pictures at:
                              >
                              > http://traildog.blogspot.com/
                              >
                              > Paul Martin
                              > Ashland, Oregon
                              >
                              > 1997 Force
                              > 48 TS 100Ah cells (now have 7,000 miles on them)
                              > Hardy BMS-48
                              > Zivan NG3
                              >
                              > [Non-text portions of this message have been removed]
                              >
                            • Wolf Packs, Inc.
                              ... Hi Mike R., Yes, the voltages are the same as last year. I used 48 cells because I was concerned about approaching the AMC325 controller s upper voltage
                              Message 14 of 14 , Dec 11, 2011
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                                > Are you still seeing the same volts as mention in the blog post on the TS pack when under load. I see you only used 48 cells and my plan is for 52. You said you would do 50 next time. Unless I messed up my math the CALB 100 should fit with a 52 count.
                                >
                                > I'll likely never do a 2600 foot climbing grade but I'm impressed that you do it regularly. Do you leave plenty of charge space for a regen down the hill or fill it up at home?
                                >
                                > Mike R
                                > 97 Force

                                Hi Mike R.,

                                Yes, the voltages are the same as last year. I used 48 cells because I was concerned about approaching the AMC325 controller's upper voltage limit. I had calculated having 3.8v X 48 cells might be too much for the controller. Since I only charge up to about 3.6v the controller would most likely handle 50 or 52 cells. Yes, 52 cells would easily fit. My front box only has 8 cells in it. I'd rather not get into the last 10% of the controller's rated capacity in an effort to avoid heat and reliability issues. Even in winter the cooling fan on my motor is on during the whole climb to get home (I leave it on for a while after I park in the garage), I'd guess the controller fans are on also.

                                I rarely charge more than a few Ah's at home. If I've run errands in town before heading up the hill and show 40+ Ah's when I get home I'll charge for an hour or so to bring the cells up a bit before sitting overnight. That's just an old habit (from the original lead pack) of me not wanting to leave the batteries with a low charge overnight. If I head down the hill with more than 25 Ah's showing on the dash meter I can use regen the whole way down instead of brakes. If it's reading less than about 25 Ah's I have to be careful not to regen the cells with too much/too fast.

                                Paul Martin
                                Ashland, Oregon
                                1997 Force
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