What are these BMS wires?

The wires coming from the BMS on the right can anyone tell me what it is?


I believe it’s a temperature sensor. Maybe someone else can explain me why it isn’t soldered on the board? I guess it’s cheaper this way?

yes it´s the temp sensor and it is soldered on, just covered with some liquid tape thing or silicone. or you mean why it´s missing on the left one?

Thanks guys. And if you know why its missing from the left one please tell me. Do I need to have one soldered on?

I meant, why is it using a cable to connect to the board? I guess heat transfer through the PCB?

The temp sensor can be placed on your battery pack. It’s another level of protection. If your battery overheats then the bms will cut power.


It should work without temperature sensors. You’ll just miss the over-temperature protection feature since the BMS will have no way of knowing the battery pack temperature.

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