Will someone help me figure out why my batteries wont charge?

I have two 4s batteries in series connected to a BMS. When I plug in the charger the light from the charger goes from green to no light at all. I am using a 24v 2amp charger.


I’m having the same issues with my setup and any help would be appreciated! this is my battery connected to the bms -

:grin: a nice little schematic for how everything is connected and a wiring diagram for your bms would increase your chances of getting this sorted! GL!


Hey !

If you have 2 4S in series, your 8S pack will need 4.2x8 = 33.6V to charge it, so 24V would be too weak. I may be wrong too but it can be your issue.

@Alex753 asked someone on this and they just said to search an 8s charger on Amazon.


If my balance wires going into my BMS are not correct will that cause the problem?

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Wiring should look like this


Why have you got 2 - phases ?

OK this makes sense thanks. One is the negative out and the other is the battery negative.

Charger input voltage is too low… You need something that can push up to 33.6v.

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