How to judge and test the capacity of lithium batteries in electric vehicles?

Professional electric vehicle lithium battery pack inspection method 1. After the battery is fully charged, connect the battery, ammeter, and resistance wire. 2. The internal circuit of the battery is open. Some electric vehicle lithium battery packs have an internal open circuit, which is manifested as the battery has voltage and no current, and the vehicle has electricity and the motor does not rotate. If the vehicle is normal after replacing a set of new batteries, it is a battery problem. 3. The green light of the charger does not change, and the green light of the charger does not change when charging. The green light of the charger is on when the charger is unloaded. Generally, it is caused by the lack of water or scarce sulfuric acid inside the battery. After opening the battery cover, unscrew the one-way Valve or safety valve, inject an appropriate amount of special replenisher into the battery, and charge for 6-10 hours to switch. How to judge and test the capacity of lithium battery in electric vehicle? 1. Use a voltmeter to add a load to detect the battery capacity. It is difficult to accurately use a voltmeter or a multimeter to check whether the battery capacity is sufficient without load. When measuring voltage alone, the current consumption is very small, so there is no large voltage drop inside the battery, so the display voltage is not low, but if you add a considerable load, such as turning on the headlights (load current 10-15A), press The horn (load current 6-12A), the battery will dim the light and the horn will be hoarse, thus indicating insufficient power storage. 2. Using a hydrometer to detect battery capacity is also a common method. Generally, the standard specific gravity of the electrolyte of a fully charged battery at 20℃ is 1.25～1.29kg/L; if the specific gravity of the electrolyte at 20℃ of the battery is less than the above value, More than 1.06kg/L, the battery has insufficient power and needs to be charged; if the battery has an electrolyte specific gravity of 1.06kg/L or less at 20°C, it means that the battery has been completely discharged or damaged. According to this principle, the capacity of the battery can be known by measuring the specific gravity of the battery electrolyte with a hydrometer, and the condition of the battery can be further judged. Disclaimer: Some pictures and content of articles published on this site are from the Internet. If there is any infringement, please contact to delete. Previous: What are the common cathode materials for lithium batteries?