Product Description

The internal pressure of a battery refers to the internal pressure of the battery, which is caused by the gas generated during the charging and discharging process of the sealed battery, and is influenced by factors such as battery material, manufacturing process, and battery structure. The main reason for its occurrence is due to the accumulation of moisture and gases generated by the decomposition of organic solutions inside the battery. Generally, the internal pressure of the battery is maintained at a normal level. In the case of overcharging or discharging, the internal pressure of the battery may increase. The battery internal pressure testing system is used to monitor the internal pressure change curve of the battery at room temperature or high temperature over a long period of time.

Reasons for the formation of internal pressure in lithium batteries

1. Normal gas production

The formation process in the production process of battery cells, which is accompanied by the formation of SEI film, is often referred to as formation gas. This gas can generally be temporarily stored in an air bag and discharged in subsequent processes without significant impact on the battery cells.

2. Abnormal gas production

After the removal and packaging of the gas bag, due to an abnormality inside the battery, there is an excessive amount of gas that cannot be discharged, causing the battery cell to swell and deteriorating its performance. When the internal pressure is too high, it is easy to open the packaging aluminum foil, causing serious damage such as leakage and corrosion

Factors contributing to abnormal gas production

① The film formation of the battery cell itself is unstable

② Excessive water content inside the battery cell

③ Short circuit inside the battery caused by

④ High temperature storage

⑤ Overcharging and discharging

During the production and testing process of lithium-ion batteries, gas generation generates pressure, which is an important cause of battery life degradation and even safety issues. Effective monitoring of gas production, internal pressure, and composition is of great significance for process optimization and product safety improvement of lithium-ion batteries.

Application of lithium battery internal pressure measurement