Lithium batteries have the following advantages and are increasingly used in daily life and other fields.
1. High energy storage density, reaching 460-600Wh/kg, which is about 6-7 times that of lead-acid batteries;
2. Long service life, generally up to six years or more;
3. High power handling capacity;
4. Low self-discharge rate.
The charging process of lithium batteries is generally divided into three stages: trickle charging, constant current charging, and constant voltage charging.
Taking a mobile phone battery as an example, when charging starts, the internal charging management chip first detects the voltage of the battery to be charged. If the voltage is lower than 3V, pre-charging is performed first, and the charging current is 1/10 of the set current. After the voltage rises to 3V, the standard charging process begins.
The standard charging process is as follows: constant current charging is performed at the set current. When the battery voltage rises to 4.20V, it switches to constant voltage charging, maintaining the charging voltage at 4.20V. At this time, the charging current gradually decreases, and charging ends when the current drops to 1/10 of the set charging current. Generally, the output voltage of a mobile phone charger is 5V, and the charging management chip inside the phone is responsible for reducing the voltage to a suitable 3.7V for the phone battery.
