Jump bike battery pack

Yesterday while I was getting off work I found a jump bike battery pack in the trash can in SF TL area. I picked it up and got it home and was able to take the casing off. Inside I found 40x lg GBMH1 18650 cells. These cells are rated as 10amp discharge and about 3200mah. All the cells seems to be in good condition and they are balanced. The battery pack is 10s4p. My plan is to take out the circuit board and put in a bms of my own.

I want to keep the battery pack intact but I could not figure out what the 2 black, yellow and red wires is for. I used a voltmeter and got no read from the black plug. I also don’t know what the white plug is for. The white plug has only 8 wires so it’s not the balance wires.

What you guys thing?

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Score, damn.
It may be broken, but I would bet it would be the circuits that died.

If you are tearing it apart does it matter what those wires are? you would be taking it down to just the 40 cell and you would know how to wire the BMS from there.

Well I was hoping I can a figure out what these cables were and be able to use it and not have to dismantle the whole battery. Just trying to be lazy.

Black plug may be main batter cable and charging cable and the white cable could be bms? I dunno lol

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Could be for an e-switch or power for GPS

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That was what I was thinking too. Maybe I might be able to track my e board with a jump app.

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And I’m pretty sure so will Jump lol.


Did you find out how to use the connecting wires?

Just fiund one as well…

No. I Ended up taking the bms and all the plugs out and replacing the bms and connect it to a scooter. The 18650 cells in that pack is 7.5amp max discharge. According to a review the cells will get damage if you used it at 10amp. I ended it using the cells in 10s4p 25 to 30 amp discharge.

And these cells are being sold my dog at $1 a cell. In here

Thx a lot

yellow and black went to the charging port on the side of the handle bars which branched off down the side of the front forks where there is some sort of charger i believe they had some type of charging rack where the bike just rolled into a bicycle charging rack. Idk i know there is some kind of contact plate on the bottom of the forks where the yellow and black wires traveled up to the handle bars and tied into that charging port on the handlebars. So the wires remain the same color and plug right into that black plug pictured . The red and black wires go from the battery to the board and power the bike . I bypassed the bms and tied the red and yellow together and both blacks together and i still got 36v well actually 42 cause i charged the battery the other white plug i have an idea, i believe they are some kind of thermal sensor they just slide into each cell i guess if it becomes unbalanced it gets hot or something along those lines .

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I dont know about the whole amp discharge i though that is controlled by the bms. Cause i had no problems or complaints when i connected to a bms 30 amp controller it was just slower then my 48v battery so i didnt use it i still have it though …