What are the protection plate and the battery management system? What does it do?

The battery protection plate can play the role of charge and discharge protection for the series and parallel battery packs, and can detect the overvoltage, overcurrent, overtemperature, undervoltage and short circuit state of each single battery in the battery pack, so as to extend the service life of the battery and avoid damage of the battery due to overdischarge. The protection plate of lithium battery is an indispensable part of lithium battery.



The protection plate of lithium battery also has the function of balanced protection, there are two ways of energy dissipation and energy conversion. Energy-dissipating equalization refers to the use of electrical resistance to dissipate the excess energy in a single cell with high power or voltage in a series of cells. Energy dissipation equalization can be divided into charging equalization, voltage fixed-point equalization and static automatic equalization.





Charging equalization: When charging, the protection plate activates equalization protection when the voltage of any of the batteries is higher than all the average voltages.



Voltage fixed-point equalization: the lithium battery protection plate is fixed at a voltage point to start equalization, which is only carried out at the battery charging end, and the equalization time is short.



Static automatic equalization: during charging or discharging, even if the battery is in static shelving state, when the voltage is inconsistent, the lithium battery protection plate will start the equalization protection until the voltage is consistent.



The transfer-energy mode is to transfer the battery with large capacity to the battery with small capacity in the way of energy storage, so as to balance the capacity of the battery, which is divided into capacity constant equilibrium and capacity fixed-point equilibrium.



Battery management system



Battery Management System (BMS) can measure the Battery voltage, and also includes the Battery protection function, Battery balance function, Battery reserve function, energy measurement function, network communication function and so on. The battery management system can prevent abnormal conditions such as over discharge, over charge and over temperature.



The existence of the battery management system is to monitor, protect and manage the lithium battery equably, so as to improve the working efficiency of the lithium battery.



Similarities and Differences between lithium battery protection plate and battery management system BMS



Both the lithium battery protection plate and the battery management system protect the lithium battery. The difference between them is:



1. The protection plate of lithium battery is composed of IC, MOS tube, resistor and capacitor elements, which is an important component of lithium battery. The battery management system, which can be edited and comes with battery management software, is relatively more intelligent and ACTS as the brain of a lithium battery.



2. Lithium battery protection plate plays an important role in the field of 3C lithium battery and power battery, while the battery management system is applied in the field of power battery.



3. The battery management system operates better than the battery protection plate, but its performance is unstable at low temperatures