The so-called slow charging is usually called home AC charging. Use AC charging piles. On the basis of the existing residential power supply system (single-phase 220 v or three-phase 380 v), a charger with a power level of 5- 10 kw (actually an AC -DC converter, the output voltage is not necessarily low) is used to convert AC into DC to charge the battery in the car. This charger can be a vertical AC charging pile or a smaller car charging pile. This kind of charging method, it is best to use low power, and the charging speed does not need to be fast. Generally, it can be fully charged in 5 to 8 hours, which will not cause too much pressure on users or battery line loads. If the timer can be installed and selected for the power consumption trough, it will not only have an impact on the power grid, but also reduce the cost of users. This will also be the most important part of promoting the charging infrastructure in the future.

Fast charging principle:

The so-called fast charging means using high-power DC charging piles, which are usually installed in public places, such as parking lots, hotels, charging stations and so on. The purpose is to make the charged vehicle replenish 50-60% electric energy in a short time (1-2h). At present, Tesla's ultra-fast charge can replenish 50% of the power in 20 minutes. However, the current battery technology, including the balancing technology of battery management system, especially the heat dissipation technology, is far from our expected requirements.

Electric vehicle (BEV) refers to a vehicle that is powered by on-board power supply and driven by motor and meets the requirements of road traffic and safety regulations. Because it has less impact on the environment than traditional cars, its prospect is widely optimistic, but the current technology is not mature.

Working principle: battery-current-power regulator-motor-power transmission system-driving car.

Reference Baidu Encyclopedia _ Electric Vehicle