Analysis of the composition and important use of lithium battery protection board

1. The composition of the protection board The reason why the lithium battery (rechargeable) needs to be protected is determined by its own characteristics. Because the material of the lithium battery itself determines that it cannot be overcharged, overdischarged, overcurrent, short-circuited, and ultra-high temperature charging and discharging, the lithium battery components of the lithium battery will always appear with an exquisite protection board and a current fuse. The protection function of lithium battery is usually completed by the protection circuit board and PTC. The protection board is composed of electronic circuits. It can accurately monitor the voltage of the battery cell and the current of the charging and discharging circuit under the environment of -40℃ to +85℃. Control the on and off of the current loop; PTC prevents severe damage to the battery in a high temperature environment. The protection board usually includes control IC, MOS switch, resistor, capacitor and auxiliary device NTC, ID memory and so on. Among them, the control IC controls the MOS switch to turn on under all normal conditions, so that the cell communicates with the external circuit, and when the cell voltage or loop current exceeds the specified value, it immediately controls the MOS switch to turn off (tens of milliseconds). Protect the safety of batteries. NTC is the abbreviation of Negativetemperaturecoefficient, which means negative temperature coefficient. When the ambient temperature rises, its resistance decreases. The electrical equipment or charging equipment is used to respond in time and control internal interruptions to stop charging and discharging. ID memory is often a single-wire interface memory. ID is the abbreviation of Identification, which means identification, and stores information such as battery type and processing date. Can play a role in product traceability and application restrictions. 2. The important use of the protection board generally requires Control (IC) to detect and control the cell voltage and the working current and voltage of the charging and discharging circuit at -25℃～85℃. Under all normal conditions, the C-MOS switch tube is turned on to make The cell and the protection circuit board are in normal working condition, and when the cell voltage or the working current in the loop exceeds the preset value of the comparison circuit in the control IC, within 15-30ms (different control ICs and C-MOS have different responses Time), the CMOS is turned off, that is, the battery discharge or charging loop is closed to ensure the safety of the user and the battery. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous post: Do you know any good maintenance methods for lithium battery packs?