1. battery can not be charged
a) The problem of charger, some chargers must detect the existence of the battery before charging.
Judgment: Remove the charger from the battery and test the output voltage of the charger. If there is a constant 14.5V voltage, it is not the problem of charger. If the measured voltage is 0, it is because the BMS low voltage protection is turn on. The charger cannot activate the battery and cannot charge the protected battery.
Solution: Need to replace the charger.
b) The battery is broken and cannot be charged.
2. The voltage is abnormal
a) when receiving the battery, the voltage of battery is very low. Reason: The battery is stored for too long, and the self -discharge time is long, which causes the voltage to fall below the BMS protection voltage. The displayed voltage is relatively low, which may only be 3V or 5V, 8V. Solution: Activate the battery and charge.
b) after charging, voltage is abnormal. Reasons: 1) Whether the correct voltage charger is used
2) The voltage will fall slowly after the lithium battery is fully charged. When the charger is just removed, the battery voltage is 14.5V. The voltage will fall to about 13.5-13.6 in a short time, which is normal.
3. Insufficient capacity
a) problem of the charger model, charging voltage is not -iron lithium battery -lithium battery charging voltage is 14.5V. such as the charger purchased with a ternary lithium battery, the charging voltage is 12.8V, and the lithium battery can only be charged to capacity of about 30% with this charger voltage. Solution: Replace the adapter charger b) There is a problem with customer discharge cuttering voltage. The capacity of lithium iron phosphate batteries refers to the power released when the voltage is placed from 14.5V to 10V. c) Large discharge multiplier. Our lithium battery standard capacity refers to the use multiplier discharge at 0.5C discharge rate, if use 1C or even 2C , and the capacity will decrease significantly. d) Low temperature environment. Low temperature has a great impact on the capacity of lithium batteries, especially below 0 degrees.
4. The battery voltage is pulled out quickly a) In the two stages of 13.7-14.5V and 12-10V, the voltage changes themselves are fast because the battery capacity is very small in these two stages. b) The battery life is insufficient. c) Large discharge multiplier. Our lithium battery standard capacity refers to at a 0.5C discharge multiplier. If the customer uses 1C or even 2C multiplier discharge, the voltage drops will be fast.
5. Slow charging a) Low temperature environment. Below 0 degrees is prohibited from charging. If forcibly charging, the charging speed will be very slow, and serious irreversible damage is caused to the battery. b) Customer charger current itself is small.
6. The voltage is lower than 10V and the battery will not be protected by BMS a) The cut -off voltage of the label is 10V, but the actual protective board detects the voltage of the cell, which may not be protected by 10V, but once it is lower than 9V, it is not normal, that is, BMS protetion is invalid.
7. The battery is severe heat and smokes (the degree of hotness) a) The discharge multiplier is too large, and the BMS heat is doubled, which will increase the heat and eventually burn the shell b) The charging voltage exceeds 30V, causing BMS damage and causing a battery overcharge. Causes the battery to heat, bulge, and smoke.
8. There is a problem with the use of the solar system a) Batteries uneven causes advance protection. The batteries connected in series (2 string or 4 string) is used, and the batteries will gradually uneven if one battery is particularly low or particularly high than other batteries. when charging, the BMS will protect before controller; when discharging, the BMS will protect before inverter, causing the system work to be abnormal. Solution: send a balancer to the customer, but it cannot be effectively solved very effective, because the balanced current of this balancer is relatively small. b) After the BMS of the entire batteries is disconnected, the all-in-one inverter or controller cannot activate the batteries (only 12V30A controller, 48V3500W all-in-one inverter and 48V5000W all-in-one inverter has activation function). Solution: 1) First remove the batteries from the controller and the inverter, put the balancer street, first allow 2 or 4 batteries to balance about to 24H-48H. then re-connect the batteries to inverter and controller.
2) Activate the batteries with solar panel(12v)