TS LFP purchase

[cowtown]

> Range is my primary interest.  I'm shooting for 120-144v of 260ah.  
> I figure that will give me up to about 750 battery amps.  From my  
> very limited experience with 96v of GC batteries that rarely gets  
> above 100 amps, that seems sufficient.  Or more than sufficient.  If  
> I'm wrong, somebody set me straight.

I've seen 3C as the discharge limit for a lot of LiFePO4 from China,  
but I wonder if TS is even up to the level of their countrymen. They  
just don't appear to expend the energy to do proper QA/QC. China has  
been our source for products that have high failure rates, but the  
same was true of Japan more than half a century ago, and now they are  
usually better than the US in that regard, but who wants to wait on  
China to catch up on their own - currently, they need outside quality  
management for that.


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[Roger Heuckeroth]

According to TS web site for the TS-LFP260AHA cell, the recommended  
discharge rate is 0.5C with a max of 2C.  You could get 3C, but only  
for short periods with quite a voltage drop. All that being said, if  
his primary interest is range, he should be OK with the TS cells if  
they meet their own specs.  Although, TS as a company has screwed a  
lot of people in our group.  Beware all sales are final, no refunds or  
exchanges seams to be their corporate philosophy.

On Jul 23, 2008, at 2:51 PM, cowtown@... wrote:

>> Range is my primary interest.  I'm shooting for 120-144v of 260ah.
>> I figure that will give me up to about 750 battery amps.  From my
>> very limited experience with 96v of GC batteries that rarely gets
>> above 100 amps, that seems sufficient.  Or more than sufficient.  If
>> I'm wrong, somebody set me straight.
>
> I've seen 3C as the discharge limit for a lot of LiFePO4 from China,
> but I wonder if TS is even up to the level of their countrymen. They
> just don't appear to expend the energy to do proper QA/QC. China has
> been our source for products that have high failure rates, but the
> same was true of Japan more than half a century ago, and now they are
> usually better than the US in that regard, but who wants to wait on
> China to catch up on their own - currently, they need outside quality
> management for that.
>
>
> _______________________________________________
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ 
> ev

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[Peter_VanDerWal]

> may survive OK. Of course they won't tell you that voltage sag will be
> like down to 1V/cell, esp. when cold and all your hardware will
> cease working for under-voltage reason, but that's now *your hardware*
> problem, not TS' problem (as far as they're concerned). *Cells* are OK,
> surviving, that's what they sell and care about. Not usability of them.

As far as TS is concerned ANY problem you have is YOUR problem, even if it
IS related to the batteries.
The batteries don't do what TS says they will do?  That's your problem.
Batteries sag to much?  That's your problem.  Batteries catch on fire?
That's your problem.  Batteries don't produce ANY voltage?  That's your
problem.

Gotta love that kind of attitude.

But, I guess if you can afford to take the gamble...that's your problem. ;-)




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[Metric Mind]

290Ah pack of LCP is I believe in Bill Dennis' car - 200Ah
and 90Ah strings in parallel.

This arrangement really has no more issues than if cells would
be identical capacity, say, 150Ah and 150Ah (if paralleled at the ends
of the string).

Roger Heuckeroth wrote:
> According to TS web site for the TS-LFP260AHA cell, the recommended  
> discharge rate is 0.5C with a max of 2C.  You could get 3C, but only  
> for short periods with quite a voltage drop.

I'll tell you what I know fist hand. TS will say you can draw 3C
as far as being OK for the battery health. This may be true, the cells
may survive OK. Of course they won't tell you that voltage sag will be
like down to 1V/cell, esp. when cold and all your hardware will
cease working for under-voltage reason, but that's now *your hardware*
problem, not TS' problem (as far as they're concerned). *Cells* are OK,
surviving, that's what they sell and care about. Not usability of them.

Now, LFP *might* be different, but you're taking their word for it.
I don't see why they should be any different if the company behind is
the same. If I were head of TS company my thinking would be:
"We knowingly supplied crap and those idiots bought it. We even
told them it was crap, so they know, and they still want our product.
It will cost us far less to produce crap and they will buy it again
if we promise good specs, so we'll be morons to spend money improving
our process/product if they'll pay the same amount anyway. Will send
them LFP crap or whatever is fashionable at the moment. Who cares
about reputation, support and other non-tangible nonsense. Dollars
pouring to our account - that's business and only that counts".

> All that being said, if  
> his primary interest is range, he should be OK with the TS cells if  
> they meet their own specs.

Sure. I was interested in range too. 2 Samples they hand picked and I
personally tested met their specs allright. So?

> Although, TS as a company has screwed a  
> lot of people in our group.

Ah, you just ignore past history of this company as if nothing happen
just because price is low and tempting. Good luck.

> Beware all sales are final, no refunds or  
> exchanges seams to be their corporate philosophy.

That's good for type of people who think there is nothing wrong
with gambling, despite mathematical prove that their chances
are miserable. Since no common sense can be applied to
urge to gamble, again then I can only wish you and all participants
best luck.

If you're capable to look beyond your pocket, just realize you're
supporting TS in what they do.

Victor


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