How to Repair a Car’s Battery

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Battery is an expensive component of cars which means it deserves your care. A poor battery replacement or a faulty repair of battery can harm your budget severely but this DIY reconditioning process for the battery is useful. This foolproof method is brought to you by CarSwitch where you can find lots of used cars for sale in UAE.

What are reconditioned car batteries?

Reconditioned car batteries are the procedure of restoring the life and charging capacity of the worn out battery. You shouldn’t throw out your old or dead cells as you can recondition them for 1 or 3 times. 

Why is reconditioning a good option?

Car owners usually throw their car batteries because they do not want to face the disappointment of utilizing batteries which are not effective. Similarly, car owners are unaware how to recondition batteries. Since batteries are expensive, it’s better to revive it to save money. 

This process is eco-friendly too because batteries are difficult to recycle. So, if you are tempted by now to consider bringing life back to your good ol’ battery, see the following guide. 

Read More: Car Maintenance Tips: 2021

Required equipment

  • Voltmeter
  • Battery charger
  • Gloves and safety goggles
  • Plastic funnel
  • 1 pound baking soda
  • Neoprene resistant
  • Screwdriver
  • 1 gallon of water
  • Plastic bucket

How to recondition car batteries

Reconditioning groundwork

First, clear the corrosion. Make your own cleaning solution by mixing 2 teaspoons of baking soda and 1 spoon of water. With a toothbrush, rub the cleaning paste on the terminals. If corrosion is heavy, get a steel wool. 

Check the battery voltage

This verification can be done by voltmeter. Simply connect the voltmeter to the terminals. The voltage should be higher than 10-volts. If it’s more than 12.6-volts, reconditioning is required. If voltage is between 10 to 12-volts, you should restore the battery to fall function. If it’s less than 10-volts, no reconditioning is needed. In case there is a zero reading, it refers to a short circuit. 

Discard the acid

After verifying the voltage, take the old acid from the battery. By using a screwdriver, focus on battery caps. The caps can be between 2 to 6. Remove all caps but before emptying the cells, test them separately in order to know whether the battery has a dead cell. After the cells are empty, take some baking soda and add it in the bucket of old battery acid. This step will neutralize the battery acid. 

Place the battery in working order

After cleaning battery acid from the battery, you have to recondition it. For that purpose, fill the cell with electrolytes again. The electrolyte is usually made of distilled water and Epsom salt. This allows the battery to charge quickly by avoiding sulfates. Then, pour it in the battery.

Lastly, charge the battery

In order to check whether the reconditioning is functioning, you need to charge the battery. However, do not put the caps back because the charging might cause the electrolyte to overflow. The charging speed should be 12-volt. Leave it on charge for 36 hours or a day. 

Afterwards, put the charger away and note readings from the voltmeter. The reading should be 12.4-volt. If you want, you can have a battery load test. 

Tips & Warnings


If you don’t utilize the batteries for some weeks or more than that, put them on a trickle charger in order to preserve performance. The stored battery slowly loses its charge which leads to the buildup of sulfur on the lead plates.

In order to restore the battery to the highest capacity, charge it for 3 to 4 nights. 


Don’t utilize tap water as it includes chemicals that negatively harm the battery. 

Since batteries contain sulfuric acid, do the reconditioning process in a ventilated area and wear safety goggles plus gloves. 

Alternatives to Epsom salt battery reconditioning

Although Epsom salt boasts the best results, you can try other alternatives in case you are out of the material. 

Aluminum sulfate

You can mix 1 pound of Aluminum sulfate with 1 gallon of boiling distilled water. Blend this mixture until it is clear. Afterwards, fill the cells with this solution and charge the battery. Resultantly, the battery will start to charge faster due to the electrolyte generated from Aluminum sulfate. Another battery reconditioning substitute is Copper sulfate. 

Read More: Unclean Used Cars in Dubai Risk Getting Fined

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