What Causes a Battery to Bulge?
2 Answers
Battery bulging occurs when the battery enters a thermal runaway state during charging. Detailed Explanation: Thermal runaway happens due to excessive charging or when the battery, after prolonged use, experiences severe water loss and sulfation, leading to increased internal resistance. The increased internal resistance causes the battery temperature to rise during charging under the influence of current. The rising temperature further increases the current, creating a vicious cycle that eventually causes the battery to deform and bulge. How to Handle a Bulging Battery: Once a battery is confirmed to be bulging, it should be replaced as soon as possible. Before replacement, it is essential to have a professional repair facility inspect and measure the vehicle's charging system and battery connections to ensure normal charging conditions and that the battery itself is not at risk of bulging due to external factors.
My car battery swelled up last year, and I later found out from a repair technician that there are quite a few reasons for this. The main issue is charging problems. If the generator regulator is faulty, causing the charging voltage to be too high, a large amount of gas will be generated inside the battery and cannot escape, causing the casing to bulge. High temperatures in summer are also a culprit. When the engine compartment reaches 40-50 degrees Celsius, the electrolyte inside the battery expands and deforms. Additionally, using a low-quality charger or tampering with the circuit can lead to excessive current, overloading the battery. Moreover, if the battery has been used for three or four years, the internal plates may age and short-circuit, causing a significant increase in heat during charging, which also makes swelling likely. If you encounter this situation, do not continue using the battery—replace it immediately, as there is a risk of leakage or even explosion.
