If your car battery is failing to hold a charge and you’re short on cash for a replacement, battery reconditioning might just do the trick.
Battery reconditioning helps revive your battery by removing the sulfate buildup that decreases its charging capacity. Depending on the battery type and the equipment you have at hand, there are different ways to recondition.
Curious to know more?
Then, let’s explore what battery reconditioning means, the steps involved in the process, and why it’s effective. We’ll also discuss when you should and shouldn’t recondition your battery.
This Article Contains:
- What Is Battery Reconditioning?
- How to Recondition a Lead-Acid Car Battery Step-By-Step
- What Are the Other Ways to Recondition a Lead-Acid Battery?
- How to Recondition Other Battery Types
- Does Battery Reconditioning Work?
- When Shouldn’t You Recondition a Battery?
- 3 FAQs about Battery Reconditioning
What Is Battery Reconditioning?
The battery reconditioning process involves removing sulfate buildup that occurs over time and replenishing the electrolyte solution. This process helps a weakened battery to function almost like new.
But why is reconditioning needed in the first place?
The lead-acid battery generates electrical energy through a chemical reaction between its electrolyte fluid (sulfuric acid and water) and lead plates. When the battery discharges, lead sulfate crystals form on the battery plates. Normally, these crystals dissolve every time the lead-acid battery recharges.
However, undercharging, prolonged discharge periods, and excessive heat can cause some lead sulfate crystals to accumulate over time. This condition (“sulfation”) results in longer charging times, less charging capacity, and decreased efficiency until it eventually can’t hold a charge. Reconditioning helps break down these sulfate deposits, improving battery performance and delaying the need for a replacement.
So, how do you recondition batteries?
Discover the process below.
How to Recondition a Lead-Acid Car Battery Step-By-Step
Reconditioning batteries is best left to a mechanic as it involves working with dangerous chemicals. Here are the steps they’ll take:
Step 1: Implement Safety Measures
They’ll wear protective gear to prevent battery electrolytes (containing sulfuric acid) from getting on their skin. The mechanic will work in a well-ventilated area in case of splashes, spills, or released fumes.
They’ll also check the car battery for damage — cracks, bloating, and leaking. If it’s physically compromised, reconditioning isn’t possible, and they’ll replace it with a new battery.
Step 2: Check the Battery Voltage
The battery voltage indicates if the battery is viable for reconditioning. Since the standard 12V car battery has six cells (2.13V each), a healthy battery reading will be around 12.6V.
To check the voltage, the mechanic will attach the voltmeter or multimeter (set to read voltage) to the battery terminals — the red cable to the battery’s positive terminal and the black cable to the negative terminal.
If the battery’s voltage reading is between 10V and 12.6V, the mechanic will begin the reconditioning process. A reading less than 10V indicates a weak battery that needs replacing.
In case the mechanic proceeds with reconditioning, here are the steps they’ll follow:
Step 3: Mix the Cleaning Solution
The mechanic will mix baking soda with distilled water in a 1:1 or 2:1 ratio to create a watery paste. This solution will act as the battery cleaner and neutralize any acid spills.
Step 4: Clean the Battery of Corrosion
They’ll detach the battery cables — the negative (-) battery terminal first, then the positive (+) terminal.
Then, they’ll apply the cleaning solution to the corroded battery terminal and scrub it with a toothbrush or steel wool. Corrosion impedes the transfer of electrical energy, so removing it from the terminals and battery posts is essential.
Alternatively, a dedicated battery terminal cleaner would also work.
Step 5: Empty the Battery Cells
Remove each battery cap and place it in a temporary container so it doesn’t get lost. If sealed, they’ll use a flathead screwdriver to pry off the battery cover and battery cell caps underneath.
Then, they’ll carefully empty the battery acid from each cell into the bucket.
Afterward, they’ll add around half-pound of baking soda to the bucket to neutralize the battery acid so it’s safe for disposal at a recycling center. If there are any battery acid spills, the mechanic will also pour the baking soda solution over it to neutralize.
Step 6: Clean the Battery Cells
With a funnel, the mechanic will fill each battery cell with the cleaning solution, replace the battery caps, and shake the battery between 30 seconds and 1 minute.
Next, they’ll open the battery caps again and empty the cleaning solution into the bucket.
Step 7: Replace the Battery Electrolyte
The next step in the reconditioning process is to dissolve 120gm of Epsom salt in 1 liter of distilled water. They may warm up the water to help dissolve the Epsom salt. Adding an Epsom salt solution can improve the electrolyte’s conductivity, helping the battery hold a charge better.
Then, fill each battery cell, cover it, and re-shake it to distribute the salt evenly.
Step 8: Recharge the Battery
They’ll set the battery in a safe area and remove the battery caps again as an additional precaution because the electrolyte solution will heat up and overflow during charging.
Connect the charger to the battery terminal — the red wire to the positive terminal, and the black wire to the negative terminal.
The mechanic will keep the charger as far away from the battery as possible, then set it to charge a very low current of 12V / 2 amps (for 36 hours). Charging at a low current allows the Epsom salt to break down the lead sulfate crystals on the battery plates.
NOTE: The mechanic can also use a trickle charger for this step. A trickle charger provides a low, steady charge which helps dissolve sulfate buildup while preventing overcharging.
Step 9: Measure the Battery Voltage
Disconnect the charger and check the battery voltage with the voltmeter. The readings should be around 12.42V. If lower, they’ll reconnect the battery charger and charge up for another 12 hours.
Step 10: Perform a Load Test
Lastly, they’ll perform a basic load test on the reconditioned battery:
- Attach the battery cover, reinstall the battery, turn the ignition key to “ON,” and switch on the high beams.
- Recheck the battery voltage (the voltmeter should read 9.6V).
Now that you know how to recondition lead-acid batteries with Epsom salt, let’s look at some other methods.
What Are the Other Ways to Recondition a Lead-Acid Battery?
There are two other reconditioning methods to restore battery capacity:
- Desulfation through pulse charging: Special chargers or desulfator devices remove lead sulfate buildup by generating high-voltage pulses while avoiding prolonged high-voltage exposure, which damages the battery.
- Use equalization charge mode on the battery charger: An equalization battery charger overcharges a battery to remove sulfate crystals and balance the cell’s voltage.
The method a mechanic will use depends on the battery’s condition and type.
Wondering which method works for different types of batteries?
Find out below.
How to Recondition Other Battery Types
Here are the different ways a mechanic may recondition your battery:
- AGM battery (Absorbed Glass Mat): Reconditioning an AGM battery involves using a charger in AGM reconditioning mode. This delivers a controlled, high-voltage pulse that gradually breaks down the lead sulfate crystals formed on your battery’s plates. Once the sulfate dissolves and the battery recovers its lost capacity, the charger transitions back to a normal charging cycle to fully charge the battery.
- Lithium-ion battery (for an electric vehicle): Mechanics use a balancing charger to charge and discharge the battery pack several times. This helps rebalance the lithium-ion cells and improve battery performance.
- Nickel-metal hydride battery (NiMH): The mechanic uses a specialized reconditioning tool for at least 20 hours to recondition a hybrid battery. This involves charging, discharging, and balancing the cells in the battery pack to restore their capacity and voltage levels.
As you can see, there are several reconditioning options depending on whether you have a lead-acid, AGM, electric vehicle, or hybrid battery.
But how effective is this process?
Does Battery Reconditioning Work?
Yes, reconditioning batteries helps restore them to optimal working conditions by removing the buildup of lead sulfate crystals that interfere with charging capacity. Car battery reconditioning can:
- Extend your battery life: Lead-acid batteries typically last three to five years. Reconditioning can extend the battery lifespan by a year or two.
- Improve battery performance: Removing the sulfate buildup allows for shorter charging times and increased capacity.
- Save costs on replacing the battery: You can save some money by not having to purchase a new battery. This is especially applicable to lithium-ion batteries in EVs, which tend to be highly expensive to replace.
- Promote environmental sustainability: Fewer batteries will be disposed of, lessening the exposure of pollutants to the environment.
Despite the obvious advantages of reconditioning, there are some occasions in which you should avoid it.
When Shouldn’t You Recondition a Battery?
A few situations where you shouldn’t recondition batteries include:
- When the battery has undergone the battery reconditioning process three times or more. Their performance degrades with every reconditioning (and age). An old battery will reach a point when it can’t be refurbished anymore.
- When you have a dead battery due to poor maintenance, overcharging, or excessive deep charging.
- When the battery has severe physical damage. In this case, you should instead get a battery replacement.
Still have some queries about battery reconditioning?
We’ll explain everything else you need to know.
3 FAQs about Battery Reconditioning
Here are the answers to some common questions on battery reconditioning:
1. How Long Do Reconditioned Batteries Last?
A reconditioned battery typically lasts around one to two years. So, if you repeat the process a few times, you can theoretically extend the battery life by at least three years.
2. When Should You Recondition a Car Battery?
You should typically perform reconditioning when the battery capacity has decreased to the point where the battery produces between 10V and 12.6V. However, if part of its plates is lost from sulfation or is severely corroded, it might not be recoverable, and a battery replacement will be necessary.
3. What’s the Difference Between Reconditioning and Recharging?
Battery recharging is simply charging up the battery for a period of time.
Whereas, the battery reconditioning process entails removing sulfate from the battery plates to restore full functioning capacity. It often consists of additional maintenance steps like cleaning terminals and replenishing electrolyte levels, which aren’t part of the recharging process.
If your car battery is dying or won’t hold a charge, but you’re unsure whether it needs reconditioning or just recharging, consult a mechanic for help.
Revive Your Dying Battery with AutoNation Mobile Service
Reconditioning extends the battery lifespan, helps save money on expensive replacements, and promotes environmental sustainability. While it won’t make your old battery last forever, it’ll undoubtedly help it go the extra mile, restoring it when it counts.
Looking for a convenient way to recondition your battery?
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