The battery management system (BMS) and battery protection board (often referred to as "protection board") have overlapping functions, but they are not completely equivalent. Their relationship and differences are as follows:
Protection Circuit Board (PCB)
Function:
Mainly used for basic protection to prevent battery damage under extreme working conditions, such as:
Overcharge protection: prevents excessive voltage.
Overdischarge protection: prevents voltage from being too low.
Overcurrent/short circuit protection: limits abnormal current.
Temperature protection (some basic models): triggered by fuses or thermistors for protection.
Application scenarios:
Lithium battery packs commonly found in small consumer electronics products such as smartphones, Bluetooth earphones, power banks, etc., have a single function and low cost.
Battery Management System (BMS)
Function:
BMS is a more complex system that includes hardware and software, with functions far beyond basic protection boards, such as:
Cell balancing: Active/passive balancing to extend battery life.
SOC/SOH estimation: Real time monitoring of State of Charge and State of Health.
Thermal management: Temperature control through heat dissipation or heating.
Communication and data recording: Interacting with external systems (such as vehicle ECU) to record fault information.
High voltage safety management (for electric vehicles): insulation monitoring, high-voltage interlocking, etc.
Application scenarios:
Used in scenarios with high requirements for safety, lifespan, and performance, such as electric vehicles, energy storage systems, and industrial equipment.
Key Differences
|Features | Battery Protection Board | Battery Management System (BMS)|
|Core functions | Basic protection (overcharge/overdischarge/overcurrent) | Protection+management (balance, monitoring, communication)|
|Complexity | Simple hardware circuit | Hardware+software, algorithm complexity|
|Cost | Low | High (especially BMS with active balancing)|
|Applicable scenarios | Consumer electronics | Electric vehicles, energy storage systems, etc|
The protection board is a simplified version of BMS, which only implements basic protection functions.
BMS is a more complete system that adds advanced functions such as intelligent management and communication on the basis of protection.
For example, a protective board is sufficient for mobile phone batteries, while the battery pack of electric vehicles must rely on BMS to ensure safety and performance.