I. Overview

The electric vehicle lithium battery protection board is a bridge between the power battery and the outside world, and determines the utilization rate of the battery. Its performance is very important to the cost and safety of the electric vehicle. It can collect, process, and store important information during the operation of the battery pack in real time, and exchange information with external devices to provide real-time alarm and protection during the operation of the battery pack. B generally adopts a distributed architecture design and consists of a master control device and multiple slave control devices.

2. Function

Overcharge protection: When the voltage of a certain string of the battery pack is greater than (overvoltage) the maximum value and the protection delay is reached, the IC controls the CMOS to turn off the charging circuit.

Over-discharge protection: When the voltage of a certain string of the battery pack is less than (under-voltage) the maximum value and the protection delay is reached, the IC controls the DMOS to turn off the discharge point loop.

Overcurrent protection: When the output current of the battery pack P+ and P- exceeds the overcurrent value, the control circuit controls the discharge DMOS to turn off the discharge circuit and stop the discharge.

Short-circuit protection: When the output current of the battery pack P+ and P- exceeds the short-circuit current value, the control circuit controls the discharge DMOS to turn off the discharge circuit and stop the discharge.

Temperature protection: When the temperature sensor reaches the temperature threshold and the protection delay is reached, the control circuit controls to turn off the charge and discharge MOS tube and stop the charge and discharge.

Balance protection: When a battery string reaches the balance voltage, the control circuit turns off the charging circuit, and when a battery string exceeds the balance voltage, the control circuit releases the voltage.