Fast charge affects the damage and life of the car battery

Date:May 06, 2019

New energy vehicles are the development trend of the future car, but limited to the basic charging facilities and the cruising range of pure electric vehicles, the sales of electric vehicles have not risen. Of course, major auto companies are also using technology iterations to increase the cruising range of their own electric vehicles or work on charging methods.

The reason why consumers buy electric cars is because they have rigid car demand, but they are limited to local license policies. However, the actual experience after purchase is relatively general, especially for users who do not have charging piles around them. It can be said that they are very charging. pain.

Limited cruising range and long charging time seem to make new energy enter a low point. How can we solve these problems? Increase the battery pack to expand the cruising range of electric vehicles; or improve battery technology to increase battery capacity; or increase the charging efficiency of electric vehicles and shorten the charging time... Among them, shortening the charging time is a relatively easy technology.

The currently built charging piles support two modes of charging: slow charging, fast charging! This is like charging our mobile phone. There are two modes: fast charge and slow charge. In fast charge mode, the battery can be fully charged quickly, at least 40% faster than slow charge. The car charging here is a similar concept, but the efficiency is much higher than the mobile phone.

However, what the riders need to know here is that fast charge and slow charge are two concepts. Slow charging is AC charging, and the time of full charge is generally 6-8 hours. In this charging mode, the battery is least damaged. Fast charging is an emergency charging method, which uses high-power DC charging (also has AC fast charging). The voltage of this DC charging is generally greater than the battery voltage. It is necessary to convert the alternating current into direct current through the rectifying device. The group's pressure resistance and protection put forward higher requirements, and the charging current is large, which is ten times or even several times that of the conventional charging current. A large amount of electrons flow from the positive electrode to the negative electrode at a very high speed. Fast charging time, usually 30 minutes will be charged 80% of the electricity, some car companies have a breakthrough in technology, can do 80% of electricity in 5 minutes! This kind of charging efficiency is really scary, but the problem is also coming, so fast charging will affect the car battery? After all, the battery of an electric car is equivalent to the three major parts of a regular car.

In theory, it will affect the battery. After all, fast charging will reduce the cycle charging life of the battery. Because the battery is converted into electric energy through chemical energy, charging is a reverse chemical reaction. Frequently charging will reduce the battery's reducing power and reduce the battery charging. Cycles.

In order to alleviate the negative effects of fast charging, a very important component of electric vehicles - BMS power management system. For electric vehicles, BMS is the core component of fast charging. The main function of BMS is to intelligently manage and maintain each battery unit, prevent overcharging and overdischarging of the battery, prolong battery life and monitor battery status. For example, when you charge a new energy vehicle, the BMS can control the input current and voltage to reduce the damage to the battery as quickly as possible. Therefore, these damages are negligible for a limited time. The importance of the battery system. In addition, the batteries are all in groups. When fast charging, some battery packs may not be fully charged under the protection condition. Long-time fast charging may cause the performance of these battery packs to decrease.

Recommendation: After a long-term fast charging of an electric vehicle, a slow charging should be performed to extend the life of the car battery pack.

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