With the rapid development of the electric vehicle industry, charging technology has become one of the key factors restricting the development of the industry, and intelligent and fast charging methods have become the development trend of electric vehicle charging technology. Today, Max Power talks about these common problems in battery charging through the topic of electric vehicle batteries.
Direct current is abbreviated as DC, also known as "constant current". Constant current is a type of direct current. It is direct current with the same magnitude and direction. It was discovered by Edison. The alternating current is referred to as AC, which refers to the current whose current direction changes periodically with time. The average current in a cycle is zero. Unlike direct current, the direction changes with time, while direct current does not change periodically.
At present, the charging of electric vehicles is mainly completed by charging piles. According to the charging method, charging piles can be divided into AC charging piles, DC charging piles, and AC-DC integrated charging piles.
Among them, AC charging has low power and requires a long charging time, but the loss to the battery is small; on the contrary, the DC charging pile has high charging power and fast charging, but the loss to the battery is also large.
Constrained by the small space in the car, the on-board charging device should not be too large, and the cooling system is relatively difficult to implement, so the charging method through the AC pile is relatively slow, so it is generally installed in the residential parking lot and other places.
The DC charging pile is different. There is a rectifier in the DC charging pile, which directly converts the output current into DC power to charge the battery, and because there is no space limitation, the power of the rectifier can naturally be made larger, and the charging efficiency is naturally higher. It is higher, so it is generally installed at the charging station beside the highway. At present, the vast majority of electric vehicles can be charged to 80% in 30 minutes when using DC charging.
According to the speed of the above two charging methods, we further divide them into fast charging and slow charging, corresponding to DC charging and AC charging respectively. Regarding the choice of DC charging piles and AC charging piles, the main difference is the difference in efficiency and battery life. You can use AC charging piles when you don’t need a car at night, and of course choose DC charging piles when you need to charge urgently.