Common Faults and Repair Methods of Lithium-ion Batteries in Electric Vehicles
I. Battery water loss fault
Its main manifestations include decreased battery capacity, which in turn leads to thermal runaway and deformation of the positive electrode plate, causing the battery to swell.
Repair method: Pry open the cover on the electric vehicle battery; open the rubber cap to expose the vent; observe the electric vehicle battery through the vent to see if it is dry, and if so, add water. Additionally, it is recommended to use a disposable medical syringe and double-distilled water. Add water cautiously, and only add more if necessary.
II. Battery Imbalance Fault
The main manifestation of this is that one or more small batteries in the battery pack are already faulty, which causes other good batteries to also be unable to function properly.
Repair method: Regarding the battery imbalance fault, users can find batteries with the same capacity, voltage, self-discharge, and internal resistance to use together.
III. Battery sulfation fault
Its main characteristic is the formation of white, hard lead sulfate crystals on the electrode plates, which are very difficult to convert into active lead sulfate during charging.
Repair method: A repair device can be used. By measuring the battery's condition, it continuously emits positive and negative frequency microparticle waves during charging and discharging. After approximately 15 hours, the hardened lead sulfate crystals in the battery can be removed. However, it should be noted that this method is generally only suitable for mild sulfation. If the sulfation is severe, the battery must be replaced.
IV. Battery Plate Softening Fault
The key manifestation of this is that the surface of the positive electrode plate gradually becomes soft and eventually becomes a paste, which leads to a decrease in battery capacity due to the decrease in surface area.
Repair method: Discharge the battery to 10.5V, then use a light bulb for deep discharge for 1 to 5 hours. Then use an activator to reactivate and repair it. This method has a certain chance of repairing the battery, but if the damage is severe, replacement is the only option.
V. Battery short circuit fault
Its main manifestation is the self-discharge caused by a small lead block at the short circuit touching the positive and negative poles, which seriously affects the battery's lifespan.
Repair method: Remove the lead slag and lead blocks at the short circuit point, and reinstall the partition paper to restore the circuit.
VI. Battery open circuit fault
Its main manifestation is that the resistance is too high due to a break in a certain part of the circuit, and the current cannot pass through normally.
Repair method: Use a multimeter to check all the internal connections of the battery, find the broken connection, and then resolder it.
Nowadays, when electric vehicle users encounter lithium-ion battery failures, they take their vehicles to repair shops or dealers for replacement. Even some electric vehicle repairmen and experts on forums and websites, when faced with inquiries from electric vehicle lithium battery users about lithium-ion battery repair, will readily say that it cannot be repaired and can only be replaced.
