I have a USB device, which does have a Li-Ion internal battery in it. The device charges the battery when plugged into a socket.
However, I don't want that battery to be used at all, I do prefer that the device only works when the device is plugged into a power socket, and uses power supply to power itself.
Battery type is Li-Ion, fully charged around 4.2V, other specs unknown.
I already tried to replace the battery with jumper cable, thinking that if the battery charger wouldn't detect voltage drop, it would fool the device to stop charging. Nothing happened however, and the device didn't turn on with power cable on.
Also tried to run the device without the battery, didn't work.
Ideas how to replace the battery from the circuit?