What is the 220v power supply in the car for?

It has the same function as household power supply, but it cannot be equipped with high-power electrical equipment.

Power supply is a device that converts other forms of energy into electrical energy. The power supply is based on the principle of "magnetic energy power generation", which uses renewable energy such as water power, wind power, tidal current, dam water pressure difference, solar energy, coal-fired oil residue and so on to generate electricity. Common power sources are dry batteries and household 1 10V-220V AC power sources.

Generators can convert mechanical energy into electrical energy, and dry batteries can convert chemical energy into electrical energy. The generator and battery itself are not charged. Its poles have positive and negative charges respectively, and the voltage is generated by positive and negative charges, which are already in the charge conductor. Only voltage is needed to generate current. When the two poles of the battery are connected to the conductor, the positive and negative charges are released to generate current, and when the charges are exhausted, the charges are exhausted.