Will both of my chargers work for my setup?

So I got two chargers for my 6S4P pack. One slow at 2amps and one fast at 5amps. I bought them from aliexpress, so I wanted to double check them to make sure they’re properly rated.

Slow charger: 25.37V and 2amps

Fast charger: 25.18V and 8amps.

Here are some pictures too, the Dymo tape is what I got when I tested them with my multimeter.

The battery and BMS.

My questions are:

  • Is it safe to use the slow charger at 2amps when the voltage is 25.37V? That could put my cells at 4.2283V if the BMS doesn’t stop it.

  • The fast charger at 8amps seem to have a good voltage, but if my calculations(8amps / number of cells in one pack which is 4 = 2amps per cell) is correct then charging a 2500mah cell at 2amps is barely on the safe side of things. Should I just scrap that charger?

If I’ve missed anything or my math is off, please correct me!


They should both be ok as long as you use a BMS

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Great, thanks!

it’s common for people to overcharge their lithium up to maybe 4.3 if they plan to use them soon as they will drop down maybe a tenth of a volt soon after taken off the charger. Dropping even more if fast charged but maybe they arent both “regulated” power sources. One says li-ion and it would be but the other…200 watts is a lot for one of those little power supplies. it would be safe with the bms but maybe try getting a voltage output after you turn on all the electricity in your house and see if it lowers the output voltage. Maybe it will drop so much, if it’s not regulated, that it wouldnt even fully charge your pack.

The description of the other one says it’s for li-on as well. I’ll look into it, thanks for the tip!