Hello everyone, was hoping you guys could help me understand whats going on with this battery schematic for a toy lion battery. What I know is that component at F1 is a fuse that has heaters in it that are heated to deliberately fry the fuse and shut down the battery permanently in the event of overcurrent, cell imbalance etc. (Problem is its overly sensitive) It appears that a mosfet Q8 performs that function by grounding the BAT+ input at fuse terminal 1. the mosfet being switched by the IC21 that is monitoring individual cell voltages for imbalances. IC 21 was a special for Sony. Q1 is also a mosfet i believe which is there to close the BAT + to the toy when its sees and enable signal from the toy (that enable depending on SMBUS comms to the toy and satisfactory parameters). What I'm most unclear about is the function of Q7 its base routes to a TI bq2040 battery gas gauge (I wonder if it performs some switching function between charging and discharging. I can reveal more of the schematic later but what i can't get my head round is the flow of current in this circuit if anyone could help me out please? I also want to know whether desoldering the link at BL2 would prevent operation whilst i experiment with recelling.
If anyone's willing to talk me through additionally each component and what functions they perform I'd learn so much I've not been able to figure out, I would be massively grateful. Also it would be good to know what the Test points would be there for?

If anyone's willing to talk me through additionally each component and what functions they perform I'd learn so much I've not been able to figure out, I would be massively grateful. Also it would be good to know what the Test points would be there for?

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