We often encounter situations where batteries cannot be charged and we are at a loss. Most people rush out to buy new replacements. But is your battery really dead? Perhaps it has just fallen into a dormant state. This article will tell you how to repair a dead battery. It will also give you some tips on battery maintenance.
Factors Causing Dead Battery
Dead batteries are caused by a variety of reasons. One reason is related to the battery itself. For example, battery quality issues, physical damage, aging, etc. Another possibility is related to the environment and usage. Incorrect storage conditions can cause water ingress and swelling of the battery.
How to Save a Dead Battery?
Step 1: Ensure that the battery itself is undamaged
Before you start repairing your batteries, check them for external damage. If the battery swells, corrodes, or leaks, it is a sign of danger. Do not attempt to repair them without professional guidance. The best way to handle these batteries is to follow recycling standards.
Step 2: Distinguishing between battery types.
Different batteries have different methods of reviving. Determine which type of battery you have in order to proceed with the repair. Common types of batteries include lithium batteries, lead-acid batteries, Ni-MH(nickel-metal hydride) batteries, and alkaline batteries. Among these, alkaline batteries are non-rechargeable and therefore cannot be repaired.
Step 3: Take different measures for different types of batteries.
Before performing any operations, ensure that you are in a well-ventilated area. Wear protective equipment or protective clothing. If possible, prepare a fire extinguisher in case the battery catches fire due to improper operation.
1. Lithium Batteries
1.0 Voltage & Internal resistance Check
If there is no obvious swelling and damage on the appearance of the battery,use the multimeter to check the voltage and internal resistance of the battery. For li-ion and lithium polymer batteries, each cell nominal voltage is 3.7 V with 2.7V cut-off.If the voltage is too low,it is likely that the battery is deep discharged and the protection circuit protects it.
For lifepo4 battery,each cell nominal voltage is 3.2V with 2.2V cut-off.If the voltage is too low,it is likely that the battery deep charged.
Check whether each cell voltage is normal.If the cell voltage is normal and consistent,then the problem is due to the battery BMS.Replace the BMS and newly assemble the battery pack.
If the cell voltage is abnormal and not consistent, then replace the abnormal cells and newly assemble the battery pack.
1.1 Solving the Problem of Poor Contact
After prolonged use, the battery may experience metal oxidation on its surface, leading to rust and other issues. This can result in poor contact with the device, affecting its performance.You can use a special cleaning agent to clean the battery and make its contact ports more sensitive.
1.2 Slow Charging after Deep Discharge
If your battery is in a state of excessive discharge in point 1.0, you need to charge it more deeply. You can use a smart charger or a multimeter, but be sure to charge slowly with a low current around 0.1C. Patience is the key to success in this process.Do Not use high current to charge the battery! If the voltage doesn’t rise after a long time charging,the battery is dead.
Some lithium battery charger don’t have the zero charging function.So when the battery voltage is 0v,the charger can’t charge the battery because the battery BMS is in a state of protection.Use the 0V lithium battery charger which can activate the BMS to charge.
Even after you are use lithium charger which supports 0V charging,the battery voltage still didn’t increase.Then you have to use a new battery.
1.3 Freezing
Freezing is a very dangerous method to revive the lithium battery. You must be careful of your safety when you use this way. When freezing, ensure that the battery is completely sealed and the freezing time does not exceed 3 hours. Allow the lithium battery to draw completely before charging.
1.4 Rebuild Battery Pack
If your lithium battery is used in a group and one or several of the batteries are unusable, you can try this way. Remove damaged batteries for repair or replacement with new batteries, then reassemble it. This process requires professional expertise. If you do not have experience in this area, please do not attempt to perform it independently.
2. Lead-acid Batteries
2.1 Treatment of sulfate battery
If your battery has already undergone sulfation, you can try using some pulse repair equipment. Through this type of professional equipment, the battery undergoes a charging-discharging cycle to eliminate sulfation.
2.2 Add water
After replacing the electrolyte in the battery with pure water, slowly charge the battery. Once the battery has recovered a certain amount of charge, the solution in the battery can be adjusted to the appropriate electrolyte concentration.
3. Ni-MH Batteries
The best way to revive Ni-MH batteries is to cycle them through charging and discharging. You can choose a safe smart charger to fully charge the battery, then slowly discharge it. Repeat this process 3-4 times, and you will see the results.
Tips for Battery Maintenance
Use the original charger to maintain battery health. Keep your battery in a dry, cool place and do not leave the battery in high temperatures for long periods of time. Even if you don’t use it often, check the battery power and recharge it every 6 month. By taking good care of it, your batteries will have a longer life.
Conclusion
That concludes this article. We hope it has been helpful for your trouble. If you have any questions about repairing batteries, please contact us at any time.
