Causes and hazards of battery bulging, and how to prevent it? ( Part 1)

battery bulging is a recurring problem during routine data center maintenance .

This abnormal phenomenon of bulging and deformation of the outer casing is not only closely related to the quality and service life of the battery itself, but also deeply limited by various factors such as the humid and rainy climate of Chengdu, the precision of temperature and humidity control in the computer room, and the matching degree of charging parameters. It hides a great safety risk.

Today, we will start from practical application scenarios to analyze the core causes of battery bulging, and tell you how to prevent the hidden dangers of battery bulging and even explosion, so as to lay a solid foundation for the safe operation and maintenance of data centers.

What are the causes of battery bulging?

1. Vent hole blocked

If the vent hole on the battery filler cap is blocked or obstructed, the gas produced during prolonged charging or excessively high charging voltage will gradually accumulate, leading to increased pressure inside the battery casing and eventually causing the battery to bulge.

2. Charging time is too long

Excessive charging current or prolonged charging time can generate a large amount of gas in a battery. Furthermore, excessive current or prolonged charging time can cause a rapid increase in electrolyte temperature , which can also lead to battery bulging.

3. Sulfation occurs on the battery plates.

If the battery plates become sulfated, the voltage of each cell and the temperature of the electrolyte will rise rapidly during charging. Bubbles will form earlier and the reaction will be more intense, which can easily lead to the battery bulging.

4. The battery’s internal plate tabs and terminals are not securely welded to the busbar .

If the tabs and terminals of the battery’s internal plates are not securely welded to the busbar, a large current discharge may cause arcing or burning at the weld due to insufficient or poor contact. This can generate sparks that ignite the hydrogen-oxygen mixture produced by the battery, leading to an explosion.

5. Electrolyte viscosity is too high

If the electrolyte viscosity is high, it will slow down the rate at which it penetrates the pores of the electrode plates, increasing internal resistance. This leads to a greater voltage drop across the internal resistance during discharge. Consequently, the electrolyte temperature rises rapidly, generating a large amount of gas. This increases the gas pressure inside the battery, causing it to bulge.

6. Insufficient electrolyte volume

As we all know, after a period of use, the electrolyte in a battery will decrease, at which point it needs to be added with electrolyte or distilled water. Overcharging after the electrolyte level has decreased can cause the battery to bulge, and may even lead to an explosion.