[RE-wrenches] 4 ways to keep a battery for a long time

[jay]

HI Ray,

I think you are right.

But for example, lithium have a really flat voltage curve, and then drop like a stone. And mostly can handle extreme C/D rates with no issue.
VS
LA which have much more of a actual curve on voltage and extreme C/D rates really impact capacity and wear.  

And for the better Lithium BMS systems are measuring each cell for voltage and temp.  And are also able to balance them with small current flow.
We need that for LA, but I don’t think it’ll happen.

jay

peltz power


> On Dec 18, 2015, at 7:44 AM, Starlight Solar Power Systems <larry at starlightsolar.com> wrote:
> 
> On Dec 17, 2015, at 11:55 AM, Ray Walters <ray at solarray.com> wrote:
> 
> ...but as far as I can tell, every other storage chemistry has similar characteristics: lower capacity at low temps, a high temp limit, non-linear cycle life depending on DOD,  Puekert's exponent relating capacity vs charge/ discharge rates, volt drop under hard discharge, etc.
> 
> R.Ray Walters
> CTO, Solarray, Inc
> Nabcep Certified PV Installer,
> Licensed Master Electrician
> Solar Design Engineer
> 303 505-8760
> 
> 
> Exception: LFP batteries are not affected by Peukerts Law. Discharging at 3C or .3C has little effect. Also, high temperature degradation rate quite a bit lower than that of lead batteries.
> 
> Larry Crutcher
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