The lithium battery protection board is a circuit board which is composed of electronic components and PCBs, and is ready to monitor the voltage of the battery core and the current of the charging and discharging circuit in a certain temperature and humidity environment, and timely control the switching of the current circuit. Since the lithium battery protection board is so important, then we should understand some common problems of the protection board. Below, the Hercules protection board will explain the problem of the internal resistance of the protection board.
The MOS internal resistance is relatively stable, and the internal resistance is large. First, it should be considered whether the internal resistance of the component FUSE or PTC is too large. If the resistance of the component FUSE or PTC does not change, check the protection board structure detection P+, P. - The value of the via between the pad and the component surface may cause a micro-break of the via and a large resistance.
If there is no problem with FUSE or PTC, check whether the MOS is abnormal: first determine if there is any problem with the soldering; secondly, the thickness of the PCB (whether it is easy to bend), because the bending may cause abnormalities in the soldering of the pin; then the MOS tube Place it under the microscope to see if it breaks. Finally, use a multimeter to test the resistance of the MOS pin to see if it is broken down.
If the internal resistance is still very large, we should use the probe to contact the protection board to see if it is in poor contact or excessive oxidation. Secondly, we should pay attention to whether there is more nickel on the battery, if the nickel on the battery Too much quantity can also cause excessive internal resistance.
Choosing a well-known, dedicated lithium battery protection board manufacturer can avoid many similar problems. After years of development, Hercules protection board has a high reputation and strength in the field of lithium battery protection board.