Battery pack function: Limiter. The battery core takes the mobile phone battery system as an example. The overcharge protection system uses the charger output voltage to be set at about 4.2V to achieve the first layer of protection, so that even if the protection board on the battery pack fails, the battery will not be overcharged. Dangerous. The second protection is the overcharge protection function on the protection board, which is generally set to 4.3V. In this way, the protection board usually does not have to be responsible for cutting off the charging current, and only needs to act when the charger voltage is abnormally high. Overcurrent protection is the responsibility of the protection plate and the current limiting plate. This is also two protection against overcurrent and external short circuit. Since overdischarge only occurs during the process in which the electronic product is used. Therefore, the general design is made by the electricity
The sub-product's circuit board provides the first protection, and the protection board on the battery pack provides a second protection. When the electronic product detects that the power supply voltage is lower than 3.0V, it should automatically shut down. If the product was not designed with this feature in mind, the protection board will close the discharge loop when the voltage is as low as 2.4V.