On Sun, 01 Sep 2002 22:30:32 -0400 Seth <[EMAIL PROTECTED]> writes:
> I just hit hondaev.org. I saw one lease return at 36,000 miles.
> One with a battery replacement at 27,000, then the lease return
> at 61,000. Another (on a different site) that had a battery replaced
> after 5 weeks of use. Those were the three detailed reports I could
> find on the web tonight. Looks like a nice battery pack at 288V
> and about 90Ah, but still having battery problems.
>
> Seth
You are making a mountain out of a molehill.
The 27,000 mile EV+ NiMH battery pack was still
*within spec*, according to the report on hondaev.org.
I remember that incident because it was so unusual.
Instead of replacing one battery module that had a
weak cell, Honda chose to replace the entire battery
pack. Speculation was that Honda wanted to do
advanced mortality studies on the remaining batteries
to project how many more years they might last.
The EV+ lease returns were primarily because
Honda ended its lease program, *not* because of
battery problems, as you have apparently assumed.
Even if there were three NiMH battery pack replace-
ments, that would be *less than 1 percent* of the
360 EV+s that were built and leased by Honda --
a very respectable battery mortality rate compared
to Lead-Acid or any other battery chemistry.
Incidentally, the Matsushita NiMH batteries used
in the EV+ were very similar, if not identical, to the
NiMH batteries used in the RAV4EV. As the
Hondaev.org site clearly points out in the opening
paragraph:
>> * To date, about 1200 Toyota RAV4 on the road
in fleet operation have had zero battery pack
replacement[s]. The batteries have virtually
zero defects, considering the number of cells,
and they do not suffer apparent degradation. <<
Please stop confusing the little "AA" NiMH
batteries that you use in your hobby experiments
with state-of-the-art NiMH EV traction batteries.
*They are worlds apart!*
Regardless of whether you are talking about
Matsushita, Ovonic or Saft NiMH EV batteries,
all of these batteries meet or exceed USABC (U.S.
Advanced Battery Consortium) Midterm life cycle
standards. Each manufacturer's battery is slightly
different, but in the case of the Saft 109 ah NiMH
mentioned earlier on this thread, these modules
have delivered in excess of 1,250 cycles to 80
percent DOD (depth of discharge) at C/3. That
is a VERY respectable number!
The primary challenge for NiMH is to get
enough of these batteries into production to
bring the price down to a projected cost of
$250/kWh. In a RAV4 EV, that would equate
to a $7,100 battery pack (plus dealer profit)
that may very well last for 8 to 10 years!
Regards,
Dave Goldstein
President, EVA/DC and
Program Development Associates
Gaithersburg, MD
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