How to recondition a car battery (step-by-step guide)

The process of restoring dead battery cells to full health and charging capability is known as battery reconditioning. But why is it even necessary to recondition in the first place? The electrolyte fluid in a lead acid battery, which is made up of sulfuric acid and water, reacts chemically with the lead plates to produce electrical energy. Crystals of lead sulfate accumulate on a battery’s plates after every discharge. Lead sulfate disperses during the recharge of the lead acid battery. Yet not all of it disappears.

Additionally, lead sulfate crystals accumulate over time, reducing the battery’s capacity for charging and discharging. Sulfation is the name of this condition. Sulfation makes the battery less efficient, requires longer charging periods, and has a lower charge capacity until it can no longer hold a charge. This is when battery conditioning comes into play. Each battery cell is cleaned of extra lead sulfate crystals during the battery reconditioning process, and the electrolyte solution is replenished, restoring the battery to a nearly new condition.

Well, in this article, you’ll learn the step-by-step guide on how to recondition a car battery and how long it takes to do that.

how to recondition a car battery

Alright then, let’s dive in!


How do you recondition a car battery

Although patience is required, battery reconditioning does not necessitate an engineering degree. You probably already have the majority of the things you’ll need at home. The necessary supply list is presented in tabular form below:

Kits:Ingredients:Specialty items:
Protective wear (e.g., safety goggles, chemical-resistant gloves, apron)1 gallon of distilled water (no tap water due to chemicals added)Voltmeter
Flathead screwdriver1 pound of Epsom saltBattery charger
Toothbrush1 pound of baking soda
Two large buckets
Steel wool or battery terminal cleaner


Here’s a step-by-step guide on how to recondition a car battery both at home or any other secured location:

Suit up and space out

Even if it’s not really complex, this is nonetheless science. It could become chaotic. Make sure the place where you’re working is well-ventilated as well.

Create a cleaning solution

To make a runny paste, mix baking soda and water 2 to 1. This concoction can be used to clean batteries and cover up acid spills.

Clean the battery

If the battery terminals are corroded, scrub the build-up off with a toothbrush after applying the cleaning paste (or a solution designed specifically for cleaning batteries) to the posts. The solution is functioning if there is a foaming reaction. For batteries with significant corrosion, use steel wool. Completely clean, wipe down, and dry the terminals.

Connect the voltmeter to check the voltage

The red wire is connected to the positive terminal, and the black cable is connected to the negative terminal, much like when you jumpstart a car. Six cells make up a typical automotive battery, and each one generates roughly 2.1 volts. A healthy battery will therefore show 12.6V. If the voltage is between 10V and 12.6V, the battery can be recharged. Replace the battery if the voltage falls below 10V.

Empty the battery cells

You haven’t had to take the car’s battery out before. But at this point, you ought to. Keep a bucket nearby, along with a pound of baking soda. Use the flathead screwdriver to pry the cell caps out from behind the battery cover. Slowly pour each cell’s contents into a bucket one at a time. Baking soda can be added as you go or after all the cells have been emptied. In either case, it will neutralize the battery acid for secure disposal at any location, such as a recycling facility.

Clean the battery cells

Pour the cleaning solution into each cell using the funnel. Replace the battery cover and cell caps securely. The battery should now be shaken for at least a minute. Open the container and dump the mixture into the old-acid waste pail already there.

Replace battery cell solution

Mix 4 ounces of Epsom salt with 4 cups of water. Stir the water until it becomes clear. in addition, the process is quicker using boiling water, although it is not required. Fill the cells with the fresh electrolyte solution using the funnel. To spread the salt evenly, cover and shake once more.

Recharge the battery

Do this step low and slow? Set up in a secure location. Removing the battery lids once again is a good idea as the electrolyte solution may heat up and possibly overflow during charging. Connect the charger at a speed of 12V/ 2 amps and place it as far away from the battery as possible. Spend 36 hours letting the battery recharge.

Test the battery

Check the battery’s condition with the voltmeter after disconnecting the charger. The average reading is 12.42V. Charge it once more for an additional 12 hours if yours is lower. When everything is in working order, run a load test by reinstalling the battery, turning the key to the “On” position, and turning on the high beams. Test the battery once more while it is under load after a few minutes. Congratulations if the voltmeter readout hits 9.6V. Your vehicle’s battery has been successfully reconditioned.

The following information only applies to lead-acid batteries. Although you don’t have to wait until a battery is completely empty to condition it, safety should always come first. The battery’s viability for reconditioning will be determined after a fast visual examination. Look for any type of broken parts, bulges, or cracks. Additionally, It is recommended to buy a new battery if the old one is not in good physical condition.

Watch the video below to have practical knowledge on how to recondition a car battery:

How long does it take to recondition a car battery?

It’s actually not that simple to respond to this question. How long it will take to successfully recondition a car battery depends on a variety of factors. This explains why a lot of individuals are able to quickly recharge their car batteries. However, a lot of people take several days or close to a month to fully recharge their automobile batteries.

Given the process for reconditioning a car battery, we can estimate that the time required is about four hours. Nevertheless, it excludes the battery’s charging time. A battery needs to be charged for between 24 and 36 hours after reconditioning. A car battery’s reconditioning process may require up to one and a half days or two days, taking into account the battery’s charging duration.

Moreover, reconditioning automotive batteries comes at a low cost. Other than your protective gear, purified water, and Epsom salts, you don’t need a lot of things. You should spend less than $20 on these materials, which is a lot less than you would pay to have the automobile battery replaced. The batteries would be a fantastic investment if you could get an extra year or two out of them.

Is battery reconditioning advantageous?

The reconditioning of vehicle batteries has a number of advantages. Most importantly, it can lengthen the battery’s lifespan. You might assume that since automotive batteries typically last five years, replacing the battery when it becomes stale and ineffective would be the standard procedure. You try reconditioning it rather than replacing it. This could increase the battery’s lifespan by one or two years, allowing you to utilize it for seven years instead. You will get the most use out of the battery with this additional time.

Unsurprisingly, this brings us right to the second advantage of a reconditioned battery: cost reduction. When you consider that a replacement battery typically costs $75, you can save a considerable sum of money. Waste reduction is an additional advantage. You use a method of recycling the battery to avoid disposing of it as well as the chemicals inside. You can also become proficient enough in this process to start your own business and earn some extra cash.

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In conclusion, prolonging a car battery’s lifespan and restoring its performance can be done in a useful and environmentally beneficial way by reconditioning it. The procedure entails a number of processes, such as desulfating the battery with specialist equipment or additives, checking and topping off electrolyte levels (for non-maintenance-free batteries), and cleaning the battery connections.

While some batteries can benefit from reconditioning, it’s important to understand that not all batteries are good candidates, particularly if they are substantially damaged or have internal issues. When working with batteries and chemicals, safety procedures including wearing protective clothing and working in a well-ventilated location should always be observed.

Environmentally concerned car owners must do routine maintenance and properly dispose of old batteries. The safest and most practical way to guarantee dependable vehicle starting and electrical performance is to replace the battery if a battery reconditioning attempt is unsuccessful or if the battery exhibits considerable wear and tear.

That is all for this article, where the step-by-step guide on how to recondition a car battery is been discussed. I hope it was helpful, if so, kindly share with others. Thanks for reading, see you around!