Car Battery Care in Winter

The car battery plays a crucial role in vehicle operation. If it fails to supply power normally, the engine and on-board electrical systems will malfunction or shut down. Meanwhile, cars consume much more power in winter than in other seasons. After entering winter, special care for the battery is quite necessary to avoid the frustration of being unable to start the vehicle.

A car battery has a service life of about two years, which can be extended with proper maintenance:

First, protect the battery from low temperatures：

Batteries are most afraid of low temperatures—their capacity in cold environments is much lower than at room temperature. A battery that works normally in a warm place may suddenly run out of power in a cold area. Therefore, before the cold season arrives, check the electrolyte level. If needed, replenish the battery's electrolyte, adjust the electrolyte specific gravity, and check its charge status; recharge if necessary. Also, clean the battery wiring harness and apply special grease for protection to ensure reliable starting and extend the battery's service life.

Second, properly store the battery when the vehicle is unused:

If the car is parked outdoors or in a cold storage for weeks without use, remove the battery and store it in a relatively warm room to prevent freezing damage. When the ambient temperature drops below -10℃, a fully discharged battery will freeze. The frozen battery must be thawed before charging; otherwise, direct charging may cause an explosion. It is best to use slow charging with a small current.

Additionally, monitor the static discharge current

After the vehicle is turned off at night, the battery is still in a discharging state. The static discharge current generated at this time is very small (usually below 0.1A), which is normal. When winter comes, have this parameter tested at a 4S shop in advance. For older vehicles, the static discharge current may reach 1A or higher, which can easily cause the battery to lose power and make it impossible to start normally the next day. Generally, a current below 0.5A is considered an acceptable normal range.

Proper use should be combined with careful maintenance, and battery maintenance is actually not complicated—you can do it yourself:

Step 1: Clean the external surface of the battery

Wipe the outside of the battery with a damp cloth to remove dust, oil, white powder, and other contaminants on the panel and terminals (i.e., the positive and negative poles) that can easily cause leakage. Regularly cleaning the battery terminals not only prevents white acid corrosion powder from accumulating but also extends the battery's service life beyond expectations.

Step 2: Check and replenish the electrolyte level (for non-maintenance-free batteries)

Open the battery's water filling caps and check if the water level is at the normal position. There are usually upper and lower limit marks on the side of the battery for reference. If the water level is below the lower mark, you must add distilled water—ordinary tap water cannot be used as a substitute. If distilled water is not available, filtered tap water can be used in an emergency. Do not add too much water; the ideal level is between the upper and lower marks. Of course, many current vehicle models are equipped with maintenance-free batteries, which are marked accordingly. Do not disassemble or assemble such batteries by yourself; if there is a fault, it is best to go to a repair shop for troubleshooting.