Lithium battery fast charge and slow charge is a relative concept, generally fast charge for high-power DC charging, half an hour can be filled with 80% of the capacity of the battery, slow charge refers to AC charging, the charging process takes 6-8 hours. The reason why fast charging is fast is caused by different charging voltage and current, and the higher the current, the faster the charging. When it is about to be full, switch to constant pressure, which can prevent the lithium battery from overcharging and can also achieve the role of protecting the battery.
The charging current and power of the slow charging of lithium batteries for electric vehicles are relatively small, which is better for the battery life, and the charging cost is low when the electricity is low. Fast charging will use a large current and power, will have a big impact on the battery pack, and will also have an impact on life. Fast charging also requires supporting equipment, such as converting AC direct current, so the cost will rise.
It should be noted that if you have been using fast charge, the lithium battery life of electric vehicles is affected. The cycle life of lithium batteries is certain, in the use of slow charging, the cycle life of the battery can usually reach more than 3,000 times, and if it has been fast charging, the cycle life will be shortened to about 1,000 times, or even lower.