A swollen Citycoco battery case is a typical dangerous fault of lithium batteries, which means the internal cells have undergone chemical deterioration and thermal runaway risks. Many riders ignore slight battery bulging and continue to use the scooter, which easily leads to serious safety accidents such as battery rupture, liquid leakage, smoking, and spontaneous combustion during riding or charging. It is crucial for all Citycoco users to clearly recognize the dangers of swollen batteries, find out the causes, and master correct disposal methods.

The essential danger of a swollen Citycoco battery lies in the irreversible failure of internal cells and accumulated safety risks. Battery bulging is caused by the decomposition of internal electrolyte of lithium cells, producing a large amount of gas that accumulates in the sealed shell, resulting in shell expansion and deformation. The swollen battery has lost the protection function of the BMS system, and the internal cell structure is loose and damaged. During riding vibration, charging heating, and temperature change, the gas pressure inside the battery will rise sharply, which may break the battery shell at any time, cause electrolyte leakage, and trigger short circuit and spontaneous combustion. Even if the battery can still supply power normally, it has completely lost safe use value and is a timed bomb for riding safety.

There are four main common causes of Citycoco battery bulging. First, long-term overcharging is the most common cause. Using mismatched chargers or charging for more than 8 hours for a long time will cause continuous overcurrent charging of the battery, leading to cell overheating and gas production. Second, severe overdischarge and long-term zero-power storage will damage the internal cell activity, cause chemical reaction failure, and produce swelling gas. Third, external damage such as battery collision, extrusion, and falling will squeeze internal cells, destroy the sealing structure, and induce bulging. Fourth, high-temperature environment use and storage, such as long-term sun exposure and high-temperature closed garage storage, will accelerate electrolyte decomposition and cause battery swelling.

Standard emergency treatment and preventive measures can avoid safety accidents. Once the battery shell is found to be swollen, stop using and charging immediately, do not squeeze, disassemble, or pierce the battery artificially, and place it in an open, cool, ventilated, and flammable-free area for isolation. It is forbidden to continue riding or charging, and do not store swollen batteries indoors for a long time. Users need to contact professional battery maintenance institutions for recycling and replacement, and must not discard them randomly. In daily use, match the original charger, avoid overcharging and overdischarging, prevent battery extrusion and high-temperature exposure, and regularly check the battery shell status, which can effectively avoid battery bulging faults and eliminate potential safety hazards.