Analysis of the causes of lithium battery bulging

Lithium battery bulging is usually caused by chemical reactions or physical changes inside the battery, which lead to gas accumulation or increased pressure, thus causing the shell to swell. The following are some common reasons:

1. Overcharge or over-discharge: When the voltage of the lithium battery is too high (overcharge) or too low (over-discharge), the electrolyte inside the battery may decompose and produce gas, causing the battery to bulge. In particular, overcharging will increase the temperature inside the battery, accelerate chemical reactions, and form gas.
2. Overheating: During the operation of the lithium battery, if the heat dissipation is poor, the electrolyte inside the battery may decompose and produce gas due to excessive temperature, which will cause bulging.
3. Internal short circuit: A short circuit inside the battery may cause a local high temperature, prompting the battery to react chemically to produce gas. Short circuits may be caused by manufacturing defects, aging, damage, or external impact.
4. Battery aging: As the battery is used for a longer time, its internal materials (such as electrolytes and diaphragms) will age, which may lead to increased internal resistance, increased temperature, and even gas generation.
5. Improper charger use: Using an unmatched charger or a low-quality charger may cause excessive charging current or unstable voltage, further increasing the burden on the battery and easily causing battery swelling.
6. Production defects: During the manufacturing process of lithium batteries, if there are quality problems such as electrolyte leakage, diaphragm damage, inconsistent components, etc., it may also cause bulging.
7. External impact or physical damage: When the battery is damaged by external impact or damage, the internal structure of the battery may be destroyed, resulting in chemical reactions to produce gas, which eventually causes battery swelling.

The key to solving lithium battery bulging is to use it reasonably, avoid overcharging and over-discharging, maintain an appropriate ambient temperature, use charging equipment that meets the specifications, and avoid battery damage.