Core Technologies of Lithium-ion Battery Chargers

Lithium-ion battery chargers must adhere to specific charging methods to ensure safety and efficiency. The most basic and commonly used charging method is constant current constant voltage (CCCV) charging.

The CCCV charging process typically includes stages such as trickle charging, constant current charging, constant voltage charging, and charging termination. Taking dedicated charging management chips such as AP5056, ME405x series, and FS4057 as examples, their typical workflow is as follows: when the battery voltage is below a threshold, trickle charging is performed first, followed by a constant current charging stage where the current is set by an external resistor. Once the battery voltage reaches the set value (e.g., 4.2V), it switches to constant voltage charging. The charging cycle terminates when the charging current drops to one-tenth of the set value.

For charging high-voltage battery packs (such as those used in electric vehicles), it must be carried out under the monitoring and control of a battery management system (BMS). The BMS manages the voltage balance of each cell within the battery pack through balancing charging technology, mainly including passive balancing and active balancing methods.

Key features of high-power fast charging technology include intelligent current management (such as switching between "turbo mode" and trickle charging based on battery status), wide voltage compatibility design, and a multi-layered safety protection system integrating overvoltage, overcurrent, short circuit, and temperature monitoring.