The methods for identifying the quality of electric vehicle batteries can be summarized as follows:
1. Observe the appearance: Check whether the battery casing has obvious damage, deformation, corrosion, or leakage. Check if the positive and negative metal terminals of the battery are rusted, and if there are any signs of disassembly on the outer packaging. Confirm if there is an anti-counterfeiting label on the battery to prevent purchasing refurbished or low-quality batteries.
2. Measure voltage and capacity: Use a voltmeter to measure the voltage of each battery separately. Under normal circumstances, the voltage of each battery should be within the nominal range. Use a capacity tester to test the capacity of the battery. Under normal circumstances, the capacity of the battery should not be less than 80% of the nominal capacity. If the capacity is too low, it indicates that the battery performance has declined.
3. Testing discharge and internal resistance: Use a specialized detector to conduct discharge tests and determine battery performance based on discharge time. For example, a new 20ah battery can generally discharge for more than 120 minutes. If the discharge time is significantly shorter than the standard value, the battery quality may be poor. Measure the internal resistance of the battery using an internal resistance tester. Under normal circumstances, the internal resistance of the battery should be within a reasonable range. Excessive internal resistance may indicate internal faults or aging of the battery.
4. Actual usage testing: Use the battery on an electric vehicle and observe its performance during driving. If the battery performance decreases, it will manifest as weak acceleration and shortened range.
5. Check charging status: Check the charging status of the battery. If the battery is fully charged but the voltage is still low, it may indicate that the battery is damaged or has poor performance.
By using the above methods, the quality of electric vehicle batteries can be comprehensively identified. If any problems are found during the testing process, it is recommended to promptly contact professional maintenance personnel for inspection and repair.