Basic functional framework of battery management system

A battery management system (BMS) is an electronic control system designed to manage batteries, including sensors, controllers, drive switches, and information communication storage modules. The core function of BMS is to monitor and control the charging and discharging process of the battery according to the use environment, so as to maximize the use of the energy stored in the battery under the premise of ensuring the safety of the battery. Click here to visit the Tycorun lithium battery designed with BMS system, which can provide more than 6 powerful protections, namely overcharge protection, overdischarge protection, high temperature protection, overcurrent protection, short circuit protection, and low voltage protection.

For different applications, the battery management system may have different functions, but there are many basic functions that are common to different application cases, such as voltage monitoring, state-of-charge estimation, and safety protection. The basic functional framework of the battery management system is:

• Battery status monitoring: battery voltage monitoring, battery current monitoring, battery temperature measurement;
• Battery status analysis: battery remaining power assessment, battery aging assessment;
• Battery safety protection: “overcurrent protection”, “overcharge and overdischarge protection”, “overtemperature protection”;
• Energy control management: battery charge control management, battery discharge control management, battery balance control management;
• Battery information management: battery information display, information interaction inside and outside the system, battery history information storage.

1. Battery status monitoring

Battery state monitoring generally refers to monitoring three physical quantities of battery voltage, current, and temperature. Battery status monitoring is the most basic function of the battery management system, and it is also the premise and foundation of other functions.

2. Battery status analysis

The battery state analysis includes two parts: the remaining battery power evaluation and the battery aging degree evaluation, the so-called SOC (State of Charge) evaluation and SOH (State of Health) evaluation.

3. Battery safety protection

Battery safety protection is undoubtedly the first and most important function of the electric vehicle management system. “Over-current protection”, “over-charge and over-discharge protection” and “over-temperature protection” are the most common battery safety protection contents.

4. Energy control management

Energy control management is often included in the category of “optimized management” of batteries, that is, it is not a basic and necessary function of the battery management system, but a reasonable energy control management mechanism can optimize the use of batteries and prolong battery life.

5. Battery information management

Since the number of batteries in an electric vehicle power battery pack is often large, a large amount of data will be generated every second. Some of these data need to be notified to the driver through the meter, some need to be transmitted to the outside of the battery management system (such as vehicle controller, motor controller, etc.) through the communication network, and some need to be saved in the system as historical data.