How Do You Know When Your Drone Battery Is Charged?

Knowing the level of charge in your drone battery is critical to make sure that it doesn’t have too little or too much because of the inherent fire hazard or flight failure problems associated with drones. You didn’t get the memo? Well, here’s all you need to know.

Most intelligent drone chargers come with LED lights that indicate the level of charging. The DJI Intelligent Flight Batteries, for instance, have four LEDs. If the first two LEDs are on, it means the battery is 0 to 50 percent charged. If all of them are on, the drone is 75 to 100 percent charged.

But there are quite a few safety precautions to take before you plug the battery into a charger because if you do it wrong, there is a high risk that the charging station will explode. Here’s a look at the specifics of charging a drone battery.

How Do I Know When My Drone Battery Is Charged

For starters, this depends on the manufacturer. Take the DJI Intelligent Flight Batteries for instance. These batteries have four LEDs on their body which indicate the level of charge the batteries have reached when they are being charged.

If you didn’t know it already, charging a drone battery is not the same as charging your phone or laptop. Extra precautions must be taken to avoid hazardous results. We will get to that in a minute. But first, let’s take a look at the question at hand.

The DJI Intelligent Flight Batteries have four LED lights: LED1, LED2, LED3 and LED4. If the first two lights are on, it means the battery is between 0 to 50 percent charging. If the first three are on, the battery is 50 to 75 percent charged and if all of them are lit, the drone battery is 75 to 100 percent charged.

You should keep it between 75 and 100 percent in case you are not going to fly the drone right away. But if not, you can wait for it to charge to 100 percent at which point all the LEDs will be off.

The thing to remember here is to never leave the charger unattended because overcharging is a real problem. We will deal with that at a later stage in this post. Before that, let’s talk about the timing and levels of charging when you first get the drone.

If you want to use it right away, like you probably would, charge it to 100 percent. But if you are going to store it away for a few days, then 70 percent is an acceptable level. You will know this if you use an intelligent charging station that allows precision charging. A couple of days before the first flight, you should charge it again to 100 percent. Ideally, after each flight, you should bring it back to 70 percent charge till the next flight.

It will interest you to know that these LEDs have another purpose too. The way they light up is also a way for the drone to give error or warning messages.

You will notice messages like ‘overcurrent in discharge’ at which point you should stop flying the drone aggressively.

If the message is ‘over temperature in discharge’ it means the battery is getting heated up and the drone will not take as much power so that the battery doesn’t get blown up.

There is also ‘low temperature in discharge’ which means the battery’s temperature has fallen. You can land the drone and run its motors to bring the temperature back to normal. In some models, using a battery warmer is also an option.

And finally, there is ‘cell damaged’ which means that the batteries are acting up and you should stop using the drone right away.

The LEDs blink in a certain pattern which also tells you that there is a problem. Check the manual and you will discover this.

  • If LED2 blinks twice per second, overcurrent has been detected.
  • If LED2 blinks three times per second, a short circuit has been detected.
  • If LED3 blinks twice per second, overcharge has been detected.
  • If LED3 blinks three times per second, an over-voltage charger has been detected.
  • If LED4 blinks twice per second, the charging temperature is too low.
  • If LED4 blinks three times per second, the charging temperature is too high.

This is why reading the manual is very important, especially with drone chargers and batteries because there is always a certain amount of risk involved in charging these devices.

As mentioned before, there are a few textbook mistakes you should avoid so that your drone and the surroundings don’t turn into a hazardous environment. Let’s see what those are.

What Not to Do When Charging a Drone Battery

If you are a first-time drone user, there are a few don’ts you should commit to memory. Here goes the list.

If your battery is fully charged but the available flight time suddenly drops, bring the drone back home. That is a mechanical fault and make sure you never charge or use that battery again.

After a flight, the drone will be hot and so will the battery. Just to make sure there is no damage, let the device and the battery cool down before you take it to the charging station.

If your drone runs on LiPo (lithium polymer) batteries, place the batteries in the battery guard bag. These are designed as fire containment spaces and in case there is a fire or an explosion, they are well equipped to limit the damage.

If the battery looks swollen or it is leaking, do not try to charge it. If there is a weird smell or noise while you are charging it, remove it immediately. If there is smoke coming out, there is no question something is wrong. So, quickly but carefully remove it.

Don’t try to charge the battery with a charger that is not approved by the manufacturer of the drone.

If the charger seems damaged in any way, do not use it.

Do not keep the charging station near flammable materials or surfaces like car seats or carpets that are conductors. Also, avoid wooden furniture and flooring etc. This is because of the inherent risk of a fire. Ceramic bowls are non-conductors and also non-flammable. So, that’s a good way to go about it.

Don’t leave the charging station unattended and after the battery is charged, don’t keep it near sources of heat.

Every drone comes with instructions on the ideal temperature in which the battery should be charged. Be sure to check the range in the manual. Typically it is between 32 and 104 degrees Fahrenheit. This is particularly important if you are charging it with the battery still inside the drone.

This one is mostly for those who race drones or enjoy flying the vehicle aggressively. If you have been flying the drone for a long time and in full throttle, the battery will drain quickly.

But it will also get hot and the process is called thermal runaway. As a result, chemical reactions will take place inside the battery and make it even hotter. Touch the battery after each flight to make sure it cools down to a point where you can hold it in your hand with ease.

Frequently Asked Questions

How Long Does It Take to Charge a Drone Battery?

This varies from one manufacturer to the other but usually it takes about 50 to 90 minutes. You can also reduce the charging time if you find a manufacturer-approved charger that has higher amperage. But don’t take that risk if you don’t absolutely know what you’re doing.

Can You Overcharge a Drone Battery?

You absolutely can. Most drone batteries need about 4.2 volts per cell. So if you go above that, the battery gets overcharged and turns into a fire hazard. But you must also remember not to charge it too little. Each of those cells needs at least 3 volts at any given point in time. If it goes above or below those levels, there is a high risk of permanent damage.

How Do I Know When My Mavic 2 Battery Is Fully Charged?

Check the user manual and monitor the pattern of the LED lights. When the battery is more than 88 percent charged all the LEDs will be on, solid (not blinking). Also, read this for additional flight guidelines.

About the author, Phil Borges

Phil Borges is a battery aficionado. He's written extensively about batteries, and he loves nothing more than discussing the latest innovations in the industry. He has a deep understanding of how batteries work, and he's always on the lookout for new ways to improve their performance.