Hello
If the battery voltage drops, eg, 3.25 V, the camera will not start. then it seems that the battery is bad, which in many cases is so. But it may be that the internal battery is no longer charged. The clips on the battery voltage to the camera can be pushed too far inside which there is no good transfer.
You can try to charge the battery. Voltage to 3.7 volts with an external power supply When the battery voltage, battery back in the camera, in most cases, the camera will do it again, for a kotrte time. The battery's going but a limited number of them. A new battery is the solution in many cases.