How to Safely Dispose of LiPo Drone Batteries

Are your batteries finally worn out, and you’re wondering how to dispose of them properly? You’re in the right place.

Like any other gadget, LiPo batteries don’t last forever. They eventually stop working due to overcharging, over-discharging, crashing, and many other issues.

So, how do you dispose of drone batteries?

To safely dispose of LiPo batteries, first completely discharge them to 0V. To discharge, you can use a balancing charger, resistors, saltwater baths, bulbs or run them down in your drone. Then take them to local e-waste centers or a recycle center. Do NOT put them in a regular trash bin.

Keep reading to learn all about safely disposing of your LiPo batteries.

How to Dispose of LiPo Batteries Safely #

The first step to disposing of a battery is discharging it. As long as the LiPo battery has no charge, it will not pose any danger to you or the environment regardless of how you choose to dispose of them. 

You probably know this by now, but it doesn’t hurt to review it again. LiPo batteries have a resting (nominal) voltage of 3.7 V. That means that in most cases, they will always have some charge ranging from 3.0V to 4.2 V. But to dispose of them, you need to get them to 0V. So, how do you discharge a LiPo battery? 

Here are some of the best ways:

How to Discharge a LiPo Battery #

Use light bulbs  #

This is one of the best and safest ways to discharge a battery. What you do is get some bulbs, preferably 12V bulbs. A 12V fan would also work.

Then, design connectors that you’ll use to connect to your battery. Once the bulbs light up, it will take 5 to 6 hours to drain the battery, and the bulbs will slowly dim until there isn’t enough charge to keep them on. 

NOTE: If you can’t find bulbs, you can use LiPo batteries as a power source to charge other batteries. That way, you can discharge the batteries even when there’s no power, or you don’t want to waste electricity.

Use them in a drone #

For some drones, such as DJI drones, you can fully discharge a battery by using it in the drone. You can either fly the drone or remove the propellers and run the motors until you deplete the batteries. This method isn’t always the best idea, however, since it wears out the motors, and you also risk causing a fire. 

Use a saltwater bath #

A saltwater bath is one of the best ways to discharge a battery. Salt is an effective conductor of electricity. So, once you dip your battery in the solution, it will conduct all the charge left in the battery, making it safe for disposal. 

Please ensure the salt solution is saturated (at least 2 lbs. of salt in a gallon of water) to ensure it’s effective. The only downside with this method is it takes days to discharge a battery completely.

Use a balancing charger #

This is another safe method for discharging batteries. Some balancing chargers are built to charge and discharge a battery. Just set the voltage you need to discharge to, which is 0V in this case, and watch it do its thing. 

Almost all LiPo batteries will have the discharge rate indicated. Be careful not to exceed that rate since you’ll cause rapid temperature build-up. Always maintain the rate or a slower rate (I will explain why in a minute). 

Use a resistor #

This is another common method of discharging a LiPo battery. All you have to do is connect a resistor to your batteries and leave it for a few hours. Resistors drain batteries slowly but effectively, preventing any abnormal heat build-up, which could cause an explosion. You can even connect several resistors to speed up the discharging process. 

When using this method, the resistor is the part that builds up heat, so handle it carefully, avoid touching it, or even dip it in a non-conductive solution, such as mineral oil or distilled water.

Safety precautions for discharging LiPo batteries #

LiPo batteries aren’t designed to be completely discharged. As a result, once you attempt to get them to 0V, they tend to swell and get very hot, and they could cause a fire. Discharge the batteries while in a fireproof bag to avoid any accidents, and don’t leave them unattended. If you realize the batteries are getting too hot, disconnect them and let them cool down, then continue the discharging process. 

Since LiPo batteries often have several cells, it’s essential to check the voltage of each cell when discharging. If one cell has a lower charge or is dead, it may cause a resistance that speeds up the temperature build-up. But you can avoid this by discharging the battery slowly.  In such a case, a balancing charger can help since you can control the rate at which you discharge a battery.

It’s also a good idea to keep a fire extinguisher and a bucket of dry sand nearby in case a fire breaks out.

Regardless of the method of discharging you choose, always solder the positive and negative wires together. This will produce a slight spark. But after that, the battery can’t hold a charge anymore, and it can safely be disposed of.

Disposing of your LiPo battery #

Now that you know how to discharge them and ensure they are safe, below is how you can dispose of your LiPo battery.

Recycling #

The best way to get rid of LiPo batteries is by recycling them. Batteries contain lead and other toxic materials that are harmful to soils, water, and vegetation. These chemicals may also be harmful to people and animals. So, check with your local area if there are any battery recycling services and ask if they can take your batteries. Some services that collect waste batteries include;

• Call2Recycle
• Walmart
• Target
• Best Buy
• Lowe’s
• Hobby Lobby
• Home Depot
• Batteries Plus Bulbs
• Battery World
• Office Works
• Battery Terminal
• Century Yuasa (Australia)
• Aldi Supermarkets (Australia)

If there isn’t a battery disposal service near you, check local hobby shops or electronic shops. They will most probably have waste bins or recycle bins specifically designed for batteries and other electronic waste.

Things to avoid when disposing of batteries #

• Never dispose of worn-out batteries with your regular trash. Even when they are discharged, LiPo batteries may still contain volatile electrolytes that would be a disaster if they ended up in a garbage truck or a landfill. What happens is that trash compacts or punctures the LiPo batteries, exposing the lithium polymer into the air and triggering a reaction. If the batteries have even a slight charge in them, there’s no telling what damage they will cause.
• Avoid driving nails into the batteries, hitting them with a hammer, or cutting them. This could lead to an explosion since you can’t control the reactions that occur. The only exception, albeit risky, is after fully discharging. If you want to check if a battery is fully discharged, you can gently drive a nail through it. If you note any smoke, the battery isn’t ready for disposal. A well-discharged battery shouldn’t have any reactivity. But instead of going through this risk, just take it to experienced handlers in recycle centers, and they’ll know to dispose of the batteries safely.
• Don’t burn the batteries. The smoke released may be toxic, and the residue produced while burning may end up in your soils or water sources.
• Avoid burying the batteries since they may still leach chemicals into the soils. Besides, if by any chance they weren’t completely discharged, they could explode if someone accidentally dug them up.

How to maintain your LiPo batteries #

I know this is a post about disposing of batteries. But some of the reasons why you need to dispose of the batteries could potentially be avoided next time around. While LiPo batteries can’t last forever (they typically last at least 300 cycles), below are some ways to extend their lifespan.

• Always charge, discharge, and store them at room temperature.
• Unless you’re disposing of them, never discharge your batteries lower than 3.0V.
• Use a balancing charger to make sure all the cells within the battery are charged equally.
• Always closely monitor the batteries as they charge. A very slight temperature change can cause a fire, burning your garage or whole house along with it.
• Always store the batteries in fireproof bags when traveling or when storing them for later use.
• Never store LiPo batteries when they’re fully charged. Discharge to 40-60% for storage.
• When traveling or storing them, make sure they don’t come into contact with metallic or other conductive objects. This could lead to a short circuit rendering the batteries unusable.
• Always charge and discharge the batteries using the manufacturer’s guidelines.
• Never use bulging or damaged batteries.
• Always have 2 to 3 batteries. That way, you won’t overly stress one battery, which speeds up the wearing process compared to alternating different batteries.
• Always let the battery cool down after using it before charging it again.

Conclusion #

And that’s it. LiPo batteries disposal is part of proper drone and RC device maintenance. Always make sure they are completely discharged before disposing of them. While some people have gotten away with throwing them in the trash after discharging them, it’s not a good idea. Always look for local recycling centers or places that collect e-waste for safe disposal.