What is the reason for the bulge of the lithium ion battery
There are two important reasons for the bulging of lithium-ion batteries. One is the production problem of the manufacturer, the production environment is harsh, the production equipment is old, etc., so that the coating of the battery is uneven, and dust particles are mixed in the electrolyte. All of these may make the lithium-ion battery pack bulge when the user uses it, or even more dangerous.
Another reason lies in the user itself. If the user uses the lithium-ion battery product improperly, such as overcharging and overdischarging, or continuously using it in an extremely harsh environment, it may also cause the lithium-ion battery to bulge.
In addition to the above two important reasons, there is one less common reason. That is, the battery has not been used for a long time, and then it has not been well preserved. When it is not used when exposed to the air for a long time, and the battery is fully charged. Since the air is conductive to a certain extent, it is equivalent to the direct contact between the positive and negative electrodes of the battery if the battery is left for too long, resulting in a chronic short circuit.
The important principle of the bulging of lithium-ion batteries is that a violent reaction similar to a short circuit occurs inside the battery, generating a lot of heat, which in turn causes the electrolyte to decompose and vaporize, and the lithium-ion battery will bulge.
