EVE GRADE A authenticity

[AshleyL]

Did a capacity test on a cell. Tested from 3.6 -2.6v. Used the chinese heater tester from Will Prowse video here

Result was 295ah. Test report has it at 308.6ah. Is this normal degradation of a 10 month old cell with allegedly zero use?

EDIT: room temp was 22-25 degrees celcius. Discharged at 20A

20A? I think you could get 300+ with lower amp drain.
295AH at 20A is quite good.

 

[Alkaline]

I have a test report for all 64 cells. They sent report before they were shipped. However the QR codes are different to the ones my test report. The ones on test report were produced End sept/start of oct. These ones are April 2023. This is a different matter, i will be taking up with them, but I would like to know if they are even actaully EVE cells. Surly B cells are different barcode?

More close up pics after taking the adhesive off.
View attachment 195464View attachment 195465View attachment 195466

Looks real to me.

 

[Alkaline]

I have a test report for all 64 cells. They sent report before they were shipped. However the QR codes are different to the ones my test report. The ones on test report were produced End sept/start of oct. These ones are April 2023. This is a different matter, i will be taking up with them, but I would like to know if they are even actaully EVE cells. Surly B cells are different barcode?

More close up pics after taking the adhesive off.
View attachment 195464View attachment 195465View attachment 195466

Nice to see my students verifying qr codes

 

[IrishG]

I should do it again from 3.65 -2.5 then?

 

[SeaGal]

I should do it again from 3.65 -2.5 then?

NO!... stop trying to measure everything - just top-balance and then use them

 

[740GLE]

Did a capacity test on a cell. Tested from 3.6 -2.6v. Used the chinese heater tester from Will Prowse video here

Result was 295ah. Test report has it at 308.6ah. Is this normal degradation of a 10 month old cell with allegedly zero use?

EDIT: room temp was 22-25 degrees celcius. Discharged at 20A

What cables did you use with the tester? 10awg at a minimum?

Either way I’d place it in service and motor on.

 

[IrishG]

What cables did you use with the tester? 10awg at a minimum?

Either way I’d place it in service and motor on.

I used the cables that came with it. 8 awg. Guesising this would amount to some lost AH in heat too

 

[LakeHouse]

I used the cables that came with it. 8 awg. Guesising this would amount to some lost AH in heat too

Nope, no loss in Ah. You’ll lose voltage, which would mean a decrease in measured energy, but Ah stay consistent. It’s why battery capacity is measured in Ah.
I’m with the others: You paid for 280Ah and got more than that. Stop trying to convince yourself you got ripped off and just use those great cells!

 

[740GLE]

Nope, no loss in Ah. You’ll lose voltage, which would mean a decrease in measured energy, but Ah stay consistent. It’s why battery capacity is measured in Ah.
I’m with the others: You paid for 280Ah and got more than that. Stop trying to convince yourself you got ripped off and just use those great cells!

Any heat in the cable is losses and will impact the readings, but 8awg should have minimal voltage drop (heat)

 

[LakeHouse]

Any heat in the cable is losses and will impact the readings, but 8awg should have minimal voltage drop (heat)

No, it really won’t affect the Ah readings, other than that the voltage drop might slightly change when the measuring device decides the end voltage occurs.
The cells don’t care if the energy flowing out is dissipated as heat in the cables or as heat in whatever you’re using to measure the capacity. They provide the same amount of total electrical charge regardless. Current can’t escape, it has to flow the whole loop between the battery terminals.
The magnitude of the current can affect the Ah rating (as can temperature of the cell, to a minor extent), but wire resistance doesn’t.