The energy storage battery management system is very similar to the power battery management system. However, the power battery system is in a high-speed electric vehicle, which has higher requirements for the battery's power response speed and power characteristics, SOC estimation accuracy, and the number of state parameter calculations.

　　1 Application scenarios of large-scale energy storage systems

　　New energy power stations, wind power or solar power stations, in order to achieve the purpose of suppressing output power fluctuations, more and more power plants are beginning to be equipped with energy storage systems.

　　Independent energy storage power stations, as the power system reform gradually enters people’s field of vision, independent energy storage power stations that rely on reselling electricity for their livelihoods have gradually emerged.

　　Microgrid, a small power supply and distribution network that contains distributed power sources, electrical loads, energy storage systems, and grid management systems. In order to ensure the continuity and stability of the load, each microgrid will be equipped with an energy storage system.

　　2 The difference between energy storage battery management system (ESBMS) and power battery management system (BMS)

　　The energy storage battery management system is very similar to the power battery management system. However, the power battery system is in a high-speed electric vehicle, which has higher requirements for the battery's power response speed and power characteristics, SOC estimation accuracy, and the number of state parameter calculations.　　 The scale of the energy storage system is extremely large, and the centralized battery management system is significantly different from the energy storage battery management system. Here, only the power battery distributed battery management system is compared with it.

　　2.1 The position of the battery and its management system in each system is different

　　In the energy storage system, the energy storage battery only interacts with the energy storage converter at high voltage. The converter takes electricity from the AC grid to charge the battery pack; or the battery pack supplies power to the converter, and the electric energy passes through the converter Convert it into AC and send it to the AC grid.

　　The communication of the energy storage system, the battery management system mainly has an information interaction relationship with the converter and the energy storage power station dispatching system. On the one hand, the battery management system sends important status information to the converter to determine the high-voltage power interaction; on the other hand, the battery management system sends the most comprehensive monitoring information to the scheduling system PCS of the energy storage power station. As shown below.

　　Ternary lithium battery.

　　Different battery types have huge differences in their external characteristics, and battery models are completely unusable. The battery management system and battery cell parameters must have a one-to-one correspondence. The detailed parameter settings of the same type of batteries produced by different manufacturers will not be the same.

　　2.5 threshold settings tend to be different. 　　 Energy storage power stations have relatively ample space and can accommodate more batteries. However, some power stations are remote and inconvenient to transport. Large-scale battery replacement is more difficult. The expectation of the energy storage power station for the battery cell is to have a long life and not to fail. Based on this, the upper limit of its operating current will be set relatively low, so that the battery core will not work at full load. Neither the energy characteristics nor the power characteristics of the battery need be particularly high. Mainly depends on the price/performance ratio.

　　The power battery is different. In the limited space of the vehicle, the battery is finally installed, hoping to maximize its ability. Therefore, the system parameters will refer to the limit parameters of the battery, and such application conditions are bad for the battery.

　　2.6 The number of state parameters required to be calculated is different between the two

　　SOC is a state parameter that needs to be calculated for both. But until today, energy storage systems do not have a unified requirement, which state parameter calculation capabilities are necessary for energy storage battery management systems. In addition, the application environment of energy storage batteries is relatively abundant, and the environment is stable, and small deviations are not easy to be perceived in large systems. Therefore, the computing power requirement of the energy storage battery management system is relatively lower than that of the power battery management system, and the corresponding single-string battery management cost is not as high as that of the power battery.

　　2.7 Passive equilibrium conditions are better for energy storage battery management systems

　　Energy storage power stations have very urgent requirements for the balance ability of the management system. The scale of energy storage battery modules is relatively large. If multiple strings of batteries are connected in series, the larger single voltage difference will cause the capacity of the entire cabinet to decrease. The more batteries connected in series, the more capacity it loses. From the perspective of economic efficiency, energy storage power stations need to be fully balanced.

　　Because of the sufficient space and good heat dissipation conditions, passive equalization can be more effective, and a relatively large equalization current is used, and there is no need to worry about excessive temperature rise. Low-cost passive equilibrium can be used in energy storage power stations.