How to Recondition Lithium-Ion Batteries

Lithium-ion batteries are preferred for many portable devices thanks to their higher voltage, energy density, and lower self-discharging rate. They also have a longer lifespan than standard lead-acid batteries, lasting about three times longer.

After using a lithium-ion battery for a couple or more years, its degradation rate starts affecting its performance. Eventually, it starts charging slowly, loses power quickly, and stops charging altogether. At this point, it’s considered dead.

Fortunately, you can bring your dead lithium-ion batteries back to life by reconditioning them. Reconditioning lithium-ion batteries restores most of their capacity, allowing you to use them for longer.

What Are Lithium-Ion Batteries?

How To Recondition Lithium-ion Batteries

These are rechargeable batteries containing lithium ions in a non-aqueous electrolyte. The electrolyte comprises lithium salt, solvents, and additives. The ions move from the negative electrode (anode) to the positive electrode (cathode) through the electrolyte during discharge. When charging, the ions move from the cathode to the anode.

Can You Recondition Lithium-Ion Batteries?

Yes, you can recondition lithium-ion batteries once they stop performing at full capacity. Reconditioning saves you the cost of a new battery, which is usually about 25% of your device’s price. It also minimizes environmental pollution that occurs from the production of new batteries.

The trick is to do it before the battery goes below its minimum voltage. When a 3.7voltage drops below 1.5volts, it’s almost impossible and too dangerous to recondition.

How to Revive Lithium-Ion Batteries?

With a few steps, you can revive your dead lithium-ion batteries. You’ll need these tools:

  • Voltmeter
  • Safety glasses
  • Power source
  • Recovery charger
  • Regular charger
  • Power source

Then, follow the following steps:

Make Sure the Battery Is in the Right Condition
Disconnect your device from its power source, turn it off, and remove the battery. Using a voltmeter, take a reading of the voltage. If the voltage is below the original, proceed with the process. But, if it’s below 1.5v for a normally 3.7v battery, it’s time to get a new one. A battery with such low voltage will get damaged if you attempt recharging, presenting a safety hazard.
Use a Recovery Charger to Charge the Battery
When a lithium-ion battery’s voltage is drained, it goes into sleep mode, making it impossible to accept a charge from a regular charger. Only a recovery charger can bring it out of this mode, allowing it to accept charge again. A regular charger that comes with a recovery feature will also work. Keep up the recovery until the battery wakes up, or as long as the manual indicates.
Use a Regular Charger
After using the recovery charger, now connect your battery back to its regular charger. Allow it to charge to full capacity. For most lithium-ion batteries, this takes about three hours.
Drain the Battery
Once the battery has charged fully, drain it completely. You can discharge it by connecting it to a high-voltage device such as a torch.
Freeze it

After discharging the battery completely, put it in an airtight bag and keep it in the freezer. Ensure that no water gets into the bag—the battery must be completely dry when getting into the freezer. Keep it in the freezer for at least 24 hours.

Thaw it
Remove the battery from the freezer and let it thaw until it reaches room temperature. This will take about 8 hours.
Charge Fully

Charge your battery to full capacity using your regular charger.

Safety Tips and Warnings When Reconditioning Lithium-Ion Batteries

The electrolyte found inside lithium-ion batteries is flammable while the cell is pressurized. The risk of explosion increases when the cells receive a special charge from a recovery charger. Therefore, always wear safety glasses when reconditioning batteries.

Tips to Extend the Lifespan of Your Lithium-Ion Batteries

From the moment of its first use, a lithium-ion battery continuously undergoes chemical reactions that cause the degradation of its various components. The degradation eventually leads to a decrease in its capacity and ability to discharge energy.

You cannot stop this degradation, but you can slow it down to ensure that your battery performs optimally for longer. Here are tips on how to extend your battery’s lifespan:
Avoid Extreme States of Charge
Charging to 100% or allowing your battery to discharge to 0% puts it under stress. Many consumer product manufacturers recommend keeping devices charged between 20-80% to avoid this.
Don't Keep in a Discharged State For Long
If your battery discharges completely, charge it soon after. Leaving it discharged for long presents the risk of an internal short circuit and the degradation of voltage, which can permanently damage the battery.
Avoid Exposure to Extreme Temperatures

Both extremely high and low temperatures accelerate the degradation of lithium-ion batteries. Excess heat increases chemical reactions inside the battery, accelerating the degradation of its components. To avoid this, store the battery or device containing it at room temperature, avoiding direct sunlight or other heat sources.

Avoid charging the battery when the temperature falls below 32 degrees Fahrenheit as it can permanently damage the battery. In low temperatures, the ions form a coating on the anode, significantly reducing energy flow through the electrolyte.  Unless you can reduce the charging rate to match the fewer ions available in the electrolyte, the battery will be damaged.

FAQs - How to Recondition Lithium-Ion Batteries?

How to Recondition Lithium-Ion Batteries? - FAQ

Does freezing a lithium-ion battery work?

Yes, freezing a lithium-ion battery works when reconditioning it. Be sure to thaw it completely after freezing before charging to avoid damage.

How do I know if my lithium-ion battery is bad?

If your battery doesn’t charge or doesn’t hold power for long, it’s bad. A battery that also takes ages to charge or warms up during charging is damaged.
While these are indications of a damaged lithium-ion battery, the surest way to tell whether it’s ruined is by measuring its voltage. If the voltage reading is lower than its original, the battery is bad.

Do lithium-ion batteries go bad if not used?

Yes, lithium-ion batteries can go bad if not used for long periods. Even when not in use, the battery cells self-discharge. While the rate of self-discharge is slow, the amount adds up when the battery is left unused for many months.

Besides the self-discharging cells, some of the battery’s internal components also consume electricity. These include the capacitors and the resistors. Over time, these two activities can lead to the draining of the battery. When the battery remains discharged for long, the voltage will drop below the original and go bad.

At what voltage is a lithium-ion battery dead?

If your 3.7v lithium-ion battery’s voltage drops to below 1.5volts, it’s dead. Most lithium-ion batteries have a nominal voltage of between 3.7v-4.2v. The minimum safe voltage is usually around 2.7v, and the manufacturers normally indicate it on the manual. When the battery goes below the indicated minimum voltage, it’s dead.

Do lithium-ion batteries have memory?

Typically, lithium-ion batteries don’t have memories. Therefore, charging your battery when it’s only partially discharged will not affect its capacity. However, research has shown that lithium-ion phosphate, a material commonly used as the cathode in these batteries, is susceptible to memory.

How many times can a lithium-ion battery be recharged?

You can recharge a lithium-ion battery about 300-500 times. This is the average number of charge cycles it can take before it starts deteriorating in holding capacity and other aspects. However, some lithium-ion batteries used in electric vehicles and other applications support higher charge cycles.

Can lithium-ion batteries be overcharged?

Lithium-ion batteries can overcharge, but modern batteries come with battery management systems that prevent this. Without this system, overcharging warms up the battery, increases its risk of blowing up, and lowers its lifespan.

Can lithium-ion batteries replace NiCd?

Lithium-ion batteries can be used to replace NiCad batteries. However, not all lithium-ion batteries can replace Nicas batteries, the replacement depends on the type of batteries and the application that you want to use them for. As a general rule of thumb, make sure that the batteries have the same voltage and size.

The Takeaway

Reconditioning lithium-ion batteries is a simple thing you can do to benefit the environment that saves you money as well—as long as you undergo the process before it reaches a minimum voltage!

James Owen

James is an engineer and a professional blogger. He has gained extensive experience over the years, handling all types of power projects. He loves to share his experiences with all things related to batteries, generators, and other power-related topics.

Scroll to Top