When a mobile phone's lithium battery begins to age, it typically exhibits the following characteristics: the voltage appears basically normal when the phone is not in use, and the battery level indicator shows almost full, but the standby time is short (it will automatically shut down after a call; when charging, the battery quickly shows as fully charged). Such batteries can be repaired and activated using the following methods!
1. Discharging. This can be done by turning on the phone to discharge or by connecting a resistor. When discharging with the phone on, the discharge should stop immediately upon powering on. When discharging with a resistor, connect a small LED with the appropriate voltage and discharge for an extended period until the LED immediately turns off upon connection. A high discharge current is preferable.
II. Activation. Connect a 12V AC power supply in series, and also connect a small light bulb or resistor in series between the batteries for current limiting. First, activate with a small current, making the control circuit AC current tens of milliamps, and maintain this for 30 to 60 minutes. Then increase the current to 1 to 2 times the battery's nominal value. For example, increase the current to 1000-2000 milliamps for a 1000-2000 milliamp, and activate for 30 to 60 minutes. During the above process, carefully observe the battery's temperature and appearance: there should be no abnormal phenomena such as overheating, smoking, or bulging. If the temperature is too high (above 40°C), reduce the current appropriately. Lithium batteries that have undergone the above activation treatment can generally be used normally, but they cannot be compared with new batteries!
