Re: battery pricing and PHEV cost-of-ownership
- jb_hybrid_ford wrote:
> OK, so NiMHs are not the best choice. <snip>The NiMH chemistry has lower specific energy than li-ion, but auto
manufacturers are already using them in mass-produced vehicles. With
the Electro Energy batteries, we will be showing that NiMH batteries can
successfully power a PHEV. Some, if not all, mass-produced PHEVs may
well use NiMH batteries for the first few years until li-ion (or yet
another chemistry) takes over.
>I have been considering lithium polymer cells to be a type of li-ion.
> As I recall Lithium Polymers had some good characterics (including
> weight) but had problems with adequate power. I haven't heard much
> talke about them.
In general, they have excellent high power handling capabilities but
equally high prices. They may or may not have safety advantages; each
product needs to be tested and evaluated separately. For example, 18650
cells can have built-in pressure cutout as well as temperature cutout
switches built in to help avoid fires, but the packaging of lithium
polymer cells may just bulge instead of activating such a built-in switch.
>This remark applied to the use of supercapacitor banks to handle peak
> Ron said: "-- and that still wouldn't affect similar peak hill-
> climbing and descent currents, which can last for minutes."
currents. The point was that there can be real value to be gained by
having the battery pack able to handle full regenerative braking, if not
acceleration, currents, rather than depending on supercaps to do so.
>I have previously talked about there being a range of EV vs. ICE
> I think that the most economical PHEV would simply lose some charge
> from an extreme downhill and require some I.C. motorized assist on
> an extreme uphill. I don't know exactly what the extremes would be,
> but I could see that at some point, the cost for a given performance
> would rise dramatically. Sometimes I think there is a desire to
> have full E.V. behavior for the first 20 miles or so, but clearly
> that's probably not the least-cost option, especially under these
> extreme conditions. <snip>
capabilities possible for PHEVs (just as for HEVs). Near one end is the
PRIUS+, which is capable of only limited EV operation in terms of both
speed and acceleration; and is capable of no more than doubling gasoline
mileage until the battery is depleted. At the other end is a serial
hybrid with a small ICE disconnected from the drivetrain and running a
generator as necessary to maintain the battery's state of charge above a
minimum. Lots of things between these extremes are possible AND WILL BE
TRIED, because no one yet knows what is optimum in the real world, and,
in fact, the optimum may vary for different costumers' driving regimes
-- just as the mildly hybridized Insight gets better highway mileage
than a Prius, but the Prius does its best in city driving.
For now, CalCars is focussing on what can be done with merely electrical
modifications to existing full hybrid vehicles, because this is where
the short-term leverage exists for quickly getting mass-produced PHEVs
into the marketplace. And even such vehicles, not originally optimized
as PHEVs, can be remarkably good! Later there will be plenty of time to
debate the fine points of PHEV optimization.
> "We model our effort on "Open Source" software development projects:Well, we are trying to balance on a razor edge here. To pursue specific
> We draw on the expertise and solutions of a broad group of experts
> and no individual owns any resulting intellectual property."
> "Since we don't keep our discussions secret, our MESSAGE ARCHIVES
> ARE OPEN to the public. We remain highly focused, relatively low-
> traffic and spam-free. In this working group, members post messages
> based on their specialties."
> And from the last post:
> > CalCars is pursuing Li-ion options that we can't yet talk about
> > publicly.
batteries, Felix and I (CalCars' two full-time volunteers) have found
that we must respect various manufacturers' needs for confidentiality.
This means that there are certain specifics and deals that we cannot
discuss in our public forum until they have reached a point where we are
able to make a public announcement, as has now occurred with Electro
Energy Inc. This is one of the limits we have found to how thoroughly a
project can be run as a public forum.
>On-topic for this list are discussions of things directly related to
> I apologize for posting items off-topic. Apparently, batteries for
> others to use fall in that category as well.
CalCars' current conversion projects, the PRIUS+ and the ESCAPE+. I
apologize that though I try to avoid it, I, too, sometimes allow myself
to be led off into more general PHEV discussions.
Ron Gremban, rgremban@...
California Cars Initiative, a nonprofit organization: http://www.CalCars.org
Moderator & Technical Lead
PRIUS+ PHEV Conversion Group: http://groups.yahoo.com/group/priusplus
- On Thu, 27 Oct 2005 15:26:38 -0700, you wrote:
>Though I won't answer all questions raised recently, I do think batteryRon:
>costs and their effect on PHEV cost-of-ownership are relevant.
>However, as technical lead for a small nonprofit organization (us) I
>have had very limited and unreliable access to volume pricing
>information. Also, what I do have is not for public disclosure.
>Therefore, I have had to get as much mileage as possible from the
>snippets of information I have acquired, as well as refrain from giving
>As clearly stated in my "Battery evaluation and production cost summary"
>of July 21, the $600/kWh NiMH price is a projection based on 150% of the
>wholesale price I was quoted for Chinese NiMH "D" cells. I just now
>remembered and looked up an approximate volume quote of $735/kWh for a
>more appropriate NiMH module from a major manufacturer. It's a little
>higher than my guess, but not out of the ballpark. Electro Energy has
>not quoted any specific prices, but they have assured us that their
>pricing will be "competitive". They are also working on a future Li-ion
>product using their unique packaging.
>For Li-ion, I projected $400/kWh from an approximate real wholesale
>price of $3 each for 18650 cells. Again, it was a tenuous strategy, but
>appears to have made sense, as a manufacturer of large-scale Li-ion
>batteries has recently estimated a high volume price of . . . $400/kWh!
Thanks for trying to answer and further clarify and explore
these battery pricing questions.
In a post a couple of weeks ago you said:
"In my "Battery evaluation and production cost summary"
message of July 21, I stated that I believe an auto
manufacturer would currently pay $600/kWh or less for a NiMH
battery pack capable of 150,000 miles, or $400/kWh for a
This confused me a bit as I mentioned, and I went back to
read your post from then. I think the confusion was that
you were stating things in terms of what an auto
manufacturer 'might be willing to pay', and not in terms of
what pricing manufacturers might be reasonably able to
offer, going forward. This latter seems to be more of what
you are clarifying here... what sort of pricing we can
guestimate might be available going forward, basing this on
a few manufacturer-side pieces of data.
In any event, I think for now you have done some good
research on battery cost and availability questions, so
thanks for going over these matters. As mentioned in
private email, it is just not possible for me and others to
avoid wondering as to how Electro Energy intends to provide
BEV/PHEV-suitable NiMH batteries when everyone else seems to
be unwilling or legally precluded (or some combination) from
doing so, but I'm not sure it's necessary to clarify that
publicly, if it is sensitive information.
You have also made some mention, if memory serves, of the
comparatively unproven nature of Lithium, and to me this
provided some explanation as to why an auto manufacturer
might want to pay a more "skeptical" price for Lithium...
taking into account that there are some unproven
life-of-battery issues there, whereas with NiMH, we (both
consumers and others) are further along in understanding the
lifetime expectations we have for NiMH in some of our
I believe you have emphasized that there is a looming
unanswered question out there as to
battery-lifetime-issues-in-PHEVs, and that these questions
are hard to answer without some years of on-road testing
(sorry for any mis-stating of the exact issue here).