During the use of lithium iron phosphate batteries, some common problems may occur, such as battery overheating, BMS protection, etc. We need to discover and solve these problems in time to ensure the safe and stable operation of the battery system. The following are some common problems and their solutions:
1. Battery overheating ❗ ❗ ❗
Common causes of battery overheating include :
l Battery charging too fast or overcharging
l Battery discharging too fast or over-discharging
l Battery management system (BMS) failure
l Ambient temperature is too high
Solutions:
l Check whether the BMS is working properly to ensure that it can monitor and control the battery temperature in time
l Adjust the charging and discharging current to avoid excessive charging and discharging of the battery
l Improve the battery heat dissipation conditions, such as adding heat sinks or fans
l Set temperature alarms and protection mechanisms for the battery system
2. The battery cannot be discharged ❗❗❗
Possible reasons :
l The battery voltage is too low, and the BMS is in low voltage protection
l The battery temperature is too low or too high, and the BMS is in low temperature protection or high temperature protection
l The discharge power is too large, and the BMS discharge overcurrent protection
Solution✅
Fill the battery fully or charge it to a sufficient level before discharging, and ensure that the discharge conditions do not exceed the range allowed by the battery.
3. The battery cannot be charged ❗❗❗
Possible reasons:
l The charger voltage may be inconsistent with the standard charging voltage of the battery, resulting in failure to charge.
l The charger has no activation function. When the battery is in the BMS low voltage protection state, the output port is disconnected. If the charger has no activation function, the battery cannot be charged.
l When the battery is in the BMS low voltage protection state, the output port is disconnected. If the solar controller has no activation function, it cannot detect the presence of the lithium battery and cannot charge the lithium battery.
Solution✅
Activate the lithium battery before charging, or replace the charger or solar controller with activation function.
4. The battery cannot be charged to the nominal maximum voltage ❗❗❗
Common reasons:
l The charging voltage of the charger is incorrect or the charging voltage and battery type of the solar controller are incorrectly selected.
l Temperature protection or charging overcurrent protection may occur during the charging process.
l When the battery is used for a long time, the consistency between the cells will change, and the battery may not be charged to the maximum voltage.
Solution✅
Select the correct charger or set the charging voltage of the solar controller to a reasonable voltage. And ensure that the charging conditions do not exceed the range allowed by the battery.
5. The battery capacity is insufficient and the measured battery capacity is lower than the rated capacity ❗❗❗
Possible reason:
Incorrect test method
Solution✅
The nominal capacity of the lithium battery refers to the capacity measured when it is charged to full power at 0.5C current and then discharged to empty power at 0.5C current in an environment of 25°C. Too low temperature, excessive charge and discharge current, and the accuracy of the measuring instrument will affect the test results.
"0.5C": For example, for a 100AH battery, 0.5C current is 0.5*100=50 (amperes)