Protective measures for lithium batteries
The lithium battery core will start to produce side effects when the charge exceeds 4.2V. The higher the overcharge voltage, the higher the risk. After a lithium core voltage is higher than 4.2V, the number of lithium atoms left in the cathode material is less than half, and the cell will often collapse, allowing the battery capacity to decline permanently. If the charge is continued, the lithium will accumulate on the surface of the negative electrode because the storage cell of the negative electrode is loaded with lithium atoms. These lithium atoms will grow dendrites from the surface of the negative electrode to lithium ions. These lithium metal crystals will pass through the separator paper to make the positive and negative poles short circuited. Sometimes the battery exploded before the short circuit occurred, because in the overcharge process, the electrolyte, such as the electrolyte, cracked the gas, causing the battery shell or pressure valve to burst and burst and let the oxygen react with the lithium atom, which was stacked on the negative surface, and then explode. Therefore, when lithium batteries are charged, the upper limit of voltage must be set before they can take into account the life, capacity and safety of batteries. The maximum charge voltage limit is 4.2V. There is also a lower voltage limit when the lithium core is discharged. When the core voltage is lower than 2.4V, some materials will start to be destroyed. Since the battery will self discharge, the longer the voltage will be, the better the discharge will not be put on the 2.4V. The lithium battery releases only about 3% of the battery capacity during the period from 3.0V to 2.4V. Therefore, 3.0V is an ideal discharge cut-off voltage.