Recent content by nonoceb

By experience, i often see sla battery died or capacity fade after long floating period (many month) without cycling just on ac charger at 13.3V. I don't know exactly why but I can't recommend using sla battery without cycling once a week.

offcourse but you will never cycle your sla battery without discharging a lot your lifepo4 battery and the goal is to use sla battery up to his end of life to remplace it by lifepo4 efficient battery. trickle charge is a loss for something you don't use everyday, non sense for me

there is absolutely no problem with mixing SLA and lifepo4 but you will need some smart logic to cycle both battery in their needs. You can setup bms to disconnect lifepo4 at 14V to charge SLA up to 14.4V For the discharge periode you can start to discharge first SLA battery to a 40-60% Soc then...

Why using spring in that case, constant pressure compression maybe? lol

plastic is not compressible, sikaflex is compressible allowing cell expansion

I try adding space between cell because if thermal wrap insulation on cell failed there is a short of 10000A @ 3.2V I chosen to make a litle grid of sikaflex 1mm thin to isolate from next cell and be able to compressing

You can use collector output for driving contactor from positive battery or emiter output for driving contactor from negative battery. Verify the max current capability of this output and your contactor current requirement. 28.3v is very high for floating mode. I never set more than 28V for...

Hi i would like to share a method to test and identify matched cells when a "big" order is coming. This time i received bulk 37cells from alibaba then i would like to pairing 4 cells by capacity and IR to paralleled setup like 4S3P. Testing cell can be very time consuming and energy consuming...

YR 1035+ is fine for our application and it's a low cost AC IR tester

high IR mean old used cell. As IR AC tester is doing fast discharge charge at 1khz for mesuring it's better doing this without external current. 0.2mOhm (280Ah) at 1C discharge = 2% heat loss, and as you can double IR AC for continous DC discharge, in reality it's 4% heat loss

good, test these cells vs your EVE cells, accuracy isn't very important

Peltier can be efficient with low voltage like 3.3V instead of 12V, i was thinking remplace dump balancing resistor by peltier module and activate balancing at 3.4V to keep them cold for charging

I would like to see a real AC IR mesurement, easy to say new harder to have a video of real mesurement

Check cell terminal connection and mesure voltage directly on cell

Teardown your welding machine, and mesure the voltage from electrolitic capacitor high voltage, then feed them with solar pannel array when your small inverter output AC current is near > 20% nominal! Switch off solar array when inverter outpout is < 10%. You have to deal with IGBT for...