Cause Analysis and Solutions of Common Problems of Solar Energy Storage Batterys
1. The voltage is inconsistent, and the individual is low
1. Large self-discharge causes low voltage
The self-discharge of the cell is large, so that its voltage decreases faster than others. The low voltage can be eliminated by checking the voltage after storage.
2. Uneven charge causes low voltage
When the battery is charged after detection, uneven charging of the cells is caused by the inconsistent contact resistance or the charging current of the detection cabinet. In short-term storage (12 hours), the voltage difference is very small, but the voltage difference is large in long-term storage. This low voltage has no quality problem and can be solved by charging. After charging during production, store it for more than 24 hours to measure the voltage.
Second, the internal resistance is too large
1. Detecting equipment differences
If the detection accuracy is not enough or the contact electric group cannot be eliminated, it will cause the display to be too large. The AC bridge method should be used to test the internal resistance.
2. The storage time is too long
Solar Energy Storage Batterys are stored for too long, resulting in excessive capacity loss, internal passivation, and increased internal resistance, which can be solved by charging and discharging activation.
3. Abnormal heating causes large internal resistance
During the processing of the cell (spot welding, ultrasonic wave, etc.), the battery is abnormally heated, which causes the thermal closure of the diaphragm, and the internal resistance increases seriously.
3. Lithium battery expansion
1. Lithium battery expands when charging
When the lithium battery is charged, the lithium battery will naturally expand, but generally it does not exceed 0.1mm, but overcharging will cause the electrolyte to decompose, the internal pressure will increase, and the lithium battery will expand.
2. Expansion during processing
Generally, abnormal processing (such as short circuit, overheating, etc.) causes the internal electrolyte to decompose due to excessive heating, and the lithium battery expands.
3. Swell while cycling
When the battery is cycled, the thickness will increase with the number of cycles, but it will not increase after more than 50 cycles. Generally, the normal increase is 0.3~0.6 mm, and the aluminum shell is more serious. This phenomenon is caused by normal battery reactions. However, if the thickness of the shell is increased or the internal material is reduced, the expansion phenomenon can be appropriately reduced.