youll need to probe and do some testing to determine which terminal is which, the battery/phone might have a part number you can reference.
you'll need a basic battery controller so you can charge and discharge safely
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youll need to probe and do some testing to determine which terminal is which, the battery/phone might have a part number you can reference.
you'll need a basic battery controller so you can charge and discharge safely
Well, for #2, there are excellent modules based on the TP4056 that cost 1$. They charge lithium-ion batteries only. So check the label (yes, I know it clearly says Li-ion but don't trust strangers on the internet for safety facing stuff...), if it says Li-ion, then these are great.
For #1, probably one of those fat traces in the flexible cable is BAT+ and the other is BAT-. I would look for a way to safely remove the plastic coating in such a way that I can't accidentally short circuit it. For example, exposing the copper for BAT+ on one side, and BAT- on the other.
I would try and find a pinout for the specific battery. The connections will include V+ and V- and then some others like batt temp, and some other diagnostics stuff. I'm not intimately familiar with newer phone batteries, you may or may not be able to get the battery to charge if you dont have the right circuitry