In the case of a battery bulge, the battery should be damaged. During the charging process, a small amount of gas is generated inside the battery, which is generally absorbed during discharge. When the battery is bulged, it generates gas inside, which is easy to cause liquid leakage, which will damage the circuit of the mobile phone and increase the explosion risk. Therefore, it should be stopped to avoid danger.
If the charging current is too large, the overcharging will increase the gas generation and increase the internal pressure of the battery, which will cause the bulging phenomenon. Avoiding overcharging is the key to reduce the bulging phenomenon.
The process of charging and discharging a lithium battery or a nickel-hydrogen battery is actually a kind of chemical reaction.
The reason why the battery will rise and bulge is probably due to overheating during charging and thermal expansion and contraction of internal materials.