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Discussion Starter · #1 ·
120732


I have this battery that I recently obtained. Its a GB Systems sinobatt.
Off the leads I get about 18.5v.

Id love to use this thing to power some/etc of an electric motorcycle.

Im a battery nub, so what do i do from here?
 

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Link to where you got them?

Link to the model cell? Any data sheets for that model?

GBS is usually LFP, is that the case here? If not any idea of the voltage range per cell?

Any idea Ah capacity of each cell?

How many cells (each has a single pair of pos/neg terminals)?

How many per parallel group (pos to pos, neg to neg)?

How many groups in series (neg to pos)?
 

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Discussion Starter · #4 ·
Looks like its a GBS-LFMP200AH
200 AH per cell
ive got 8x cells in a block
each has a single pair of pos/neg, but the pos is on one side and neg on the other.

Ill have to look at the grouping
 

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If that's LFP as I assume, and no parallel but 8S

intended to be a 24V nominal pack.

Then your 18.5V comes out to 2.31Vpc

which is way below what anyone knowledgeable who cares would allow, implies abuse to me, maybe past end of life.

Do you know the usage history?

GBS is well respected, and such a pack treated properly should last a very long time. (should have lasted?)

But maybe you'll be lucky.

Most propulsion use cases would require a much higher voltage.

Might be OK for a lower C-rate use case, solar storage or House bank for a camper or boat
 

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Discussion Starter · #6 ·
Yeah, i plan to use this in a vanagon.
I got it from a company that was using it to power projectors in remote locations. they closed down and dumped this pack. Its been sitting in a warehouse for about 1.5 years.
 

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First verify exactly what it is, be 100% sure.

Here I will assume

LFP 8S, 200Ah nominal 24V

Do you want to keep that or go to 2P4S, 12V nominal 400Ah ?

Get a charger, or power supply, at least 20A, 40A better, 80A best for 200Ah, could go to double that for 400Ah configuration but that's getting very expensive unless you get lucky

ideally adjustable voltage

For 12V a 13.8V charge setpoint would be good, double that for 24Vnom.

Make sure you have a good DMM and ammeter, do not trust the readouts built into your charge source.

Also ideally get a coulomb-counting wattmeter or battery SoC monitor to determine how much of that original 200Ah per cell is remaining (State of Health).

He idea is to lowly gently charge the pack up to the setpoint, then cycle it down with a low steady load.

Watching, logging both charging and discharging cycles.
 

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You aren't talking about using this for EV propulsion are you? Just House oads like charging screens, lights, fans etc while camping off grid right?
 

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There's a chance then even if abuse has murdered 80% of its cycle lifespan, could mean a few years eft of low C-rate usage.

New would cost well over a grand USD, more with shipping costs these days, so if it works at all certainly worth a couple hundred
 
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