Lithium battery pack protection board equalization charging principle and analysis of electric equalization function

Principle of balanced charging of lithium battery pack protection board When the lithium battery pack is charged, the positive and negative poles of the external power supply of the lithium battery pack protection board are respectively connected to the positive and negative poles of the battery pack, BAT+ and BAT-, and the charging current flows through the positive electrode BAT+ of the battery pack and the battery pack. Medium single-cell lithium battery 1～N, discharge control switch device, charge control switch device, lithium battery pack protection board negative electrode BAT-. The charging over-voltage protection control signal of the single-cell lithium battery protection chip in the control circuit part of the lithium battery pack protection board system is isolated by the photocoupler and output in parallel to supply the gate voltage for the conduction of the charging switch device in the main circuit; such as a certain section Or several lithium batteries enter the over-voltage protection state during the charging process, and the over-voltage protection signal controls the discharge of the shunt discharge branch connected in parallel to the positive and negative ends of the single-cell lithium battery, and at the same time connects the corresponding ones in the charging circuit in series. The single lithium battery is disconnected from the charging circuit. While charging and protecting the lithium battery pack protection board system, the protection chip controls the on and off of the shunt discharge branch switch device to achieve balanced charging. This method is different from the traditional method of achieving balanced charging on the charger side, and reduces the lithium battery. The cost of the design and use of the charger. Lithium battery protection board electric equalization function 1. When the battery voltage of each battery in the battery pack is different due to the matching of the battery or the influence of the external environment, if the battery voltage difference between the series connected groups exceeds the set value, the equalization circuit is allowed to work, Equalization starts during the charging process, the equalization resistor discharges the battery pack with the highest relative capacity, and the equalization current is the equalization absorption current value to reduce the voltage rise of the battery pack. 2. When the voltage difference of each group of batteries in series is less than the set value , Forbid the equalization circuit to work, without any equalization. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous post: What is a lithium battery? What are the critical issues facing the recycling of lithium batteries