On Mon, 7 Jul 2008 20:14:45 -0700 (PDT), OHMyGod! <
[hidden email]> wrote:
>
>Have you considered the Seiden Batteries 3.2 @ 100AH?
>They also make packs to your measurements with BMS.
>
http://www.seidenbattery.com/product_vehicles.asp>96v 100ah, it is 4153.9USD, and for the BMS, it is 869.67USD,
>about $138 US each
>For the 96v 200ah, it is 8307.69USD, and for the BMS, it is 987USD.
>about $277 US each.
Any idea what kind of Li chemistry these use? Unless I'm missing it, I don't
see the chemistry described on that page.
This brings up something that I've been pondering for awhile. Suppose I'm in
a large warehouse full of LiFePo batteries. Is there any quick AND reliable
test that I could do to ensure that each battery that I selected was good?
Terminal voltage, of course. High current voltage sustain. Internal
impedance? What else?
The notion that has been kicking around in the back of my mind is this.
Suppose we got up a group buy large enough to buy a container full of
batteries. They could then be purchased directly from the Chinese
manufacturer.
The amount of money and the number of batteries involved would make it
practical and advisable to send someone to the factory to select the batteries
from the production run. The incremental cost for this individual would be
small to each person in the group.
My question is, is there any test or series of tests that could be applied to
each battery under consideration in a short period of time, say, under 2 or 3
minutes, that would reliably pick out the good batteries? The quantity of
batteries involved would preclude a thorough full discharge test.
I suspect that if we went directly to the factory with a container-full order,
the price of these batteries would probably come very close to what we're
paying "retail" for lead-acid batteries.
If such a group buy were to come about, I'd certainly be good for a couple
hundred volts' worth. I might even be willing to manage the project. But
only if there is some method to reliably select out the bad cells and pick the
good ones.
John
--
John De Armond
See my website for my current email address
http://www.neon-john.comhttp://www.johndearmond.com <-- best little blog on the net!
Tellico Plains, Occupied TN
I'm going crazy. Wanna come along?
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