>> I've checked out some Chinese battery suppliers and seems prices are
>> around 100
>> dollars a cell.
That is probably without the shipping, customs and duties. which is
about another 20%. Of course you don' have to turn in old batteries,
which now have a core charge of about 20%.
A 144v pack will be 45 or so cells. Should yield a 50
>> mile
>> usable range on the Ford Aspire.
Is this the car we have heard about over the years? Glad to hear it
is still on the road, I thought I heard it had an accident at one
time?
The 144v system draws 500 to
>> 700 amps
By loosing some of the weight, you won't be drawing quite so much current.
>> max. Lawrence Rhodes
>>
>
> Another thought is to replace just a few of your lead-acids with lithiums.
> Maybe replace a 12v 100ah battery with 4 100ah lithiums? Charge them
> separately, with a small charger/BMS system. Add some instrumentation, so
> you can watch the current and voltage sag relative to the lead-acids, and
> see if they are better or not.
>
> If your first candidate turns out not to be that good, try some different
> ones. You aren't out much money, and the old ones will still be a good 12v
> battery to use in something else.
I have been doing this for a while, and it may be like trying to sort
and categorize snow flakes ! I could almost say, that I have
never met two cells that were the same ! Some of the things that I
have observed are: The batteries when they are brand new and all come
from the same Lot Shipment, will all act very much the same. Getting
a replacement and adding it IN to the pack, even though it may be the
exact same battery and manufacturer, may not act the same. ( this is
why I have my customers order 5 extra cells at the time of
purchase)...Once batteries have been abused, by over discharge, or
over charging, they start to act different... Too heavy a load on
the batteries seems to be hard on them even though they say 5C or
7C... People who have large ah packs (160ah 180ah).. seem to do
better than the 100ah people that are trying to replace lead acid with
the same size in Lithium.
It would be great if someone would put together a battery pack using
all the different cells and over the next 100,000 miles we might know
how things were a few years ago. Of course by the time this test is
done, the new batteries will be different than what the original test
batteries were.
>Does this violate the balanced battery pack doctrine? It would be
interesting to see how that pack fared against the rest of the pack and it
wouldn't take much more effort to instrument them from inside the cab.
Just run a couple of $4.00 volt meters into the passenger compartment.
>
I did this a while back, and was really surprised at how well Lithium
seems to store ah compared to Lead Acid. My set up let me charge
all batteries at once or just the lithium... or just the lead acid.
And I found the Lithium used about 25% less ah. At the time, I had
100ah Lithium mixed with 100ah Lead Acid, so the Lead Acid would give
me about 50ah of run time. One problem with all this "Scientific
Research" .. is that it becomes very time consuming. This would be a
great job to have if you could be paid by the hour !! Just like
counting the grains of sand on the beach.
Lee makes a very good point about people who have had good or bad
results with their batteries. But have only bought one set.
I hope everyone will keep posting about their experiences and I would
encourage everyone that is experimenting with these batteries to keep
some kind of track of what they are experiencing, Ah, decay over
time, over discharge, over charge results, damage and for those that
have mastered the art of Lithium Husbandry what are your secrets? :-)
Steve Clunn
sean
--
Steve Clunn
Merging the best of the past with
the best of the future.
www.Greenshedconversions.com
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