What are the basic test methods for the capacity of lithium-ion battery electric vehicles?

The capacity tester can be used to measure the capacity of lithium-ion batteries in electric vehicles. What kind of battery is discharged according to what kind of discharge current, until the cut-off voltage. Electric vehicle lithium-ion battery capacity detection generally uses constant electricity to discharge electricity to the shielding voltage under the condition of 25 ℃, and the battery capacity is obtained by multiplying the discharge time and the discharge current. The method of measuring battery capacity is basically the same as that of lithium-ion battery discharge function detection. There are constant current discharge method, constant resistance discharge method, constant voltage discharge method, constant voltage constant current discharge method, continuous discharge method and intermittent discharge method. The capacity of the battery can be calculated according to the discharge time and the size of the current. 1. Use a voltmeter to add a load to detect the battery capacity. It is difficult to accurately use the voltage of a voltmeter or a multimeter without adding a load to check whether the battery capacity is rich or not. When measuring voltage alone, the current consumption is 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), honking the horn (Load current 6-12A), the battery will make the lights dim and the horn hoarse, indicating that the battery is insufficient. 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 lithium-ion battery at 20°C is 1.25~1.29kg/L; if the battery is at 20°C, the electrolyte specific gravity is less than If the above value is greater 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, operating a hydrometer to measure the specific gravity of the battery electrolyte can identify the battery capacity and further determine the battery's condition. 3. Use a battery tester to detect battery capacity. In daily care and maintenance, it is really possible to quickly and accurately test how much battery capacity is. Li-ion battery tester should be used as usual. When using, connect the lithium ion battery tester to the battery for 10-15 seconds, and keep the voltage at 10.5～11.6V, which implies that the capacity is rich and the battery is not obstructed; if the voltage is kept at 9.6V～10.5V, it implies that the capacity is insufficient and the battery is not obstructed; The voltage drops below 9.6V, which implies that the capacity is severely insufficient or the battery is obstructed. 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 basic repair methods for lithium-ion battery electric vehicle batteries?