The lithium-ion battery protection board provides charge and discharge protection for series-connected lithium-ion battery packs. When fully charged, it ensures that the voltage difference between individual cells is less than a set value, achieving equal charging of all cells in the lithium-ion battery pack and effectively improving the charging effect under series charging. At the same time, it detects the overvoltage, undervoltage, overcurrent, short circuit, and overtemperature conditions of each individual cell in the battery pack, protecting and extending the battery's lifespan. Undervoltage protection prevents each individual cell from being damaged due to over-discharge during discharge.
Commonly used equalization charging techniques for lithium-ion battery protection boards include constant shunt resistor equalization charging, on/off shunt resistor equalization charging, average battery voltage equalization charging, switched capacitor equalization charging, buck converter equalization charging, and inductor equalization charging.
When charging a series of lithium-ion batteries, it is essential to ensure that each cell is charged evenly; otherwise, the performance and lifespan of the entire lithium iron phosphate battery pack will be affected during use. However, existing single-cell lithium-ion battery protection chips do not include equalization charging control functionality. For multi-cell lithium-ion battery protection chips, equalization charging control requires an external CPU; this is achieved through serial communication with the protection chip, increasing the complexity and design difficulty of the protection circuit, reducing system efficiency and reliability, and increasing power consumption.
The equalization principle of lithium-ion battery protection boards can protect and equalize power lithium-ion battery packs of any structure and voltage level by changing the protection chip model and number in series, as well as the power level of switching devices and energy-consuming components in the circuit, according to the application requirements.
