12s battery charges only 48 volt full, but should be 50,4 volt any help with that?

I built an 12s8p battery pack with smart bms. But it would not charge more then 48volt before the charger stops. Can anyone please help with some info?
The board run great, but i cant stop thinking about it. It built with 40t 2100 cells

If you have a smart BMS, can you send us a picture of what the app looks like when it’s done charging?

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If you have a multimeter check your charger, You may have a charger issue.

Is there any chance the charger stops but doest shut off?

What kind of bms do you have? Ive seen a few that will only charge the battery to 48v even though full is 50.4

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For me, the guage of b- on the bms to main negative was too small.

BMS settings most likely.

Looks like the bms is shutting off the charge at 48v.

Normally you see the current fall as it goes into the constant voltage stage

But your charging profile ends after the CC stage. So the charger is most likely set to 50.4v, but the BMS is set to 48v. Change it to 50.4 in the app and you will get a few more miles of range.

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I am having this issue currently. At 48V the BMS shuts off and does not start balancing.

Dumb BMS… not had time yet to take the case apart but I can imagine its buggered and needs BMS swapped. or could be a bad cell can only find out.

I had to Get a new BMS and then the problem was ok. Had somthing to do with my bms.
So now it Charles up to 50.4


My issue was 3 of the cells had gone off balance. When charging stopped at 48V most cells were at 4.1V (balance start) and the three on the - end were at 4.0 volts. For some reason the BMS refused to balance as I left it plugged in for 12+ hours and no voltage change.

I took the BMS out, manually balanced all to 4.1V and seems to be fine now.

So sometimes dumb BMS need a kick in the pants to start working, even .1V out of balance can be too much I guess idk.

I had ro do the same, had to rip up the battery pack, and balance all to same level, but still it wouldent charge more then 48 volt until i bought a new smart bms. But works just fine now =)