Battery processing unit (BMU) and battery maintenance

The continuous development of battery processing unit (BMU) and battery maintenance battery materials has raised the upper limit of thermal runaway temperature. On the other hand, although the battery has to undergo strict UL safety tests, such as UL1642, the system planner is still responsible for supplying the correct charging conditions and responding well to many possible electronic component defects. Overvoltage, overcurrent, short circuit, overheating, and defects of external discrete components may cause the battery to suddenly fail. This means adopting multiple maintenance requirements at least two independent maintenance circuits or mechanisms in the same battery pack. In addition, there are electronic circuits to detect thin short circuits in the battery to prevent battery defects. The voltmeter circuit is programmed to accurately indicate the available capacity of the lithium battery. The general algorithm of the circuit allows real-time search of battery pack storage changes, battery impedance, voltage, current, temperature and other circuit information. The battery meter actively calculates the charge and discharge rate of the battery, the self-discharge rate and the aging rate of the battery unit, which ends the high-precision electric energy measurement within the battery life. For example, a series of patented impedance seeking voltmeters, including bq20z70, bq20z80, and bq20z90, provide measurement accuracy of up to 1% during battery life. A thermistor is used to monitor the temperature of the lithium battery to end the battery overheating maintenance and charging and discharging beams. For example, the battery is generally not allowed to be charged in a temperature plan below 0°C or above 45°C. When the battery temperature exceeds 65°C, it is not allowed to discharge. If overvoltage, overcurrent or overheating is detected, the voltmeter IC will instruct the AFE to turn off the charging and discharging MOSFETs Q1 and Q2. When detecting that the battery is in an undervoltage state, the AFE should be instructed to turn off the discharging MOSFETQ2 and turn the MOSFET over to charge the battery. The important task of AFE is to detect overload and short circuit, and maintain the charge and discharge of MOSFET, battery and other components on the line to prevent overcurrent. Overload detection is used to detect overcurrent (OC) in the direction of battery discharge. Short circuit (SC) detection is used to detect overcurrent in the direction of charge and discharge. The binding and delay time of the overload and short circuit of the AFE circuit can be programmed through the data flash of the electric energy meter. When an overload or short-circuit condition is detected and the delay time set by the program is reached, the charge and discharge MOSFETs Q1 and Q2 will be turned off. The specific status information will be stored in the AFE status register, and the battery meter can read and query the cause of the defect. 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: What should the research and development of digital batteries focus on?