What is the purpose of the 12V socket in the trunk?

[VanGrace]

The 12V socket in the car trunk is used for: connecting to 12V electrical appliances such as car refrigerators, car vacuum cleaners, projectors, etc. Here is additional information: 1. Check if the charger is damaged: Whether the charging parameters meet the requirements: the initial charging current should reach 1.6-2.5A per cell; the maximum charging voltage should reach 14.8-14.9V per cell, the charging to floating charge transition current should reach 0.3-0.4A per cell, and the floating charge voltage should reach 14.0-14.4V per cell. 2. Check if the battery is dry inside: Whether the battery is severely lacking in electrolyte, and also check if the plates have irreversible sulfation. The irreversible sulfation of the plates can be determined by measuring the change in terminal voltage during charge and discharge. During charging, the battery voltage rises very quickly, with some cell voltages being particularly high, exceeding normal values by a lot; during discharging, the voltage drops very quickly, and the battery does not hold or holds very little charge. If the above conditions occur, it can be judged that the battery has irreversible sulfation.