DJI batteries are incredibly intelligent and, unfortunately, this can mean that they are very easy to kill. There are several different ways that a DJI battery may die and, sometimes, you can resurrect it.
If you think your DJI battery is dead you can try and revive it by direct charging, using the DJI repair tool (DJI battery killer) or hard resetting the battery by removing the outer casing and internal ribbon cables.
DJI batteries have a small processor that increases their life during storage and use. It monitors the amount of charge in the battery so that it minimises the risk of over or under-charging your drone battery.
Sometimes, the processing unit errs on the side of caution and stops your battery from working. In this instance, you will be able to revive your battery. However, sometimes the battery is dead because of a breakdown of the internal lithium polymer chemistry and will need to be replaced.
Here is how you can work out if your battery can be revived and why DJI batteries die.
Why DJI batteries die
Unlike other drone batteries (like those seen in racing drones) the DJI batteries are manufactured to fit snugly into the drone and each has a small processor that runs on the battery power that is constantly monitoring the state of the battery.
The current drawn from the processor means that the battery will continue to deplete quicker than other non-smart batteries.
If your battery is in storage for a long time the cell voltage could drop below a “lock limit”.
The lock limit of 2 V per cell indicates to the processor that the battery should be placed into a permanent failure state.
If your drone battery is dead after a long time of storage you may use special software to revive your drone as long as the cell voltages have not dropped to 0.
The battery can still be recovered as long as you cannot see any swollen parts of the casing and the recharge counter is not above 300 cycles.
If you want to try to revive a DJI battery that has been in storage for too long here is what you can try.
How to (maybe) fix a dead DJI battery:
Fixing a dead DJI battery can be quite a technical undertaking.
You should not attempt to fix your dead DJI battery if it is showing any signs of damage or bulging. Trying to fix a drone battery that is visibly damaged may cause an explosion.
DJI battery repair tool (DJI Battery Killer)
One option for a dead DJI battery is to use a software called DJI battery repair tool.
This tool can help you repair your battery and kick it out of the permanent failure state.
If that doesn’t work, you can try charging your battery for a longer time. You can also try using a different charger.
Let’s talk about more options, below.
Hard reset the battery
Warning, this section is for confident or capable drone pilots.
Some drone pilots have been able to revive a battery that they considered dead.
Because drone batteries are so expensive, many drone pilots ask themselves, “what is the harm?” when trying to hack their battery back to life.
Here is how you revive a drone battery with a hard reset. You will need to open up the plastic casing of the drone battery and record the polarity of the battery using a multimeter.
How to hard reset a drone battery
There are many examples on online forums of reviving a drone battery. For example, Richard on a DJI forum board was able to revive his dead battery using the process below.
1) remove the top off the battery and slowly pull back the casing to see the inside.
2) Look for the only wire you can “remove” without desoldering the joins. Use chopsticks or other non-metal tools to remove the connection.
3) Keep the connection unplugged for 2 hours
4) Insert the wire back, and the LED lights may return.
5) Put the latest firmware upgrade on the Micro SD card prior to turning the battery on while in the Inspire
6) Charge the battery as normal and fly with caution.
If you are going to attempt to hard reset your battery, be sure to test it thoroughly before sending it out for a full flight.
Charging the DJI battery in different ways can help provide a seemingly dead smart battery. The two proven methods that have worked in forums and online are not using the charging hub and connecting the battery directly to a charger with alligator clips.
Not using a hub
Some drone pilots have been able to revive a dead DJI battery by directly charging it using the official DJI charger.
Try and charge your drone battery using the officially supplied DJI battery charger and not the hub which can accommodate multiple drone batteries.
Other drone users have been able to resurrect their DJI battery from the dead by making a jumper lead with two alligator clips.
Here is what one drone pilot did to get their drone battery working again.
Disconnected the balance plug. Made a jumper with 2 alligator clips. Jumpered the ground from the charge jack to the ground on the cells (large black wires). Charged the batteries for 10 minutes as if they were ni-cads. Took them off charge, and plugged the balance plug back in. Put them back on charge.
These types of interventions require a lot more expertise and electrical know-how than others and you must proceed with caution if you decide to start to take your drone battery apart. Shorting the battery and connecting wires that are not meant to be connected can cause a fire and explosion.
How to look after your DJI battery
Ensuring that you look after your DJI battery appropriately will be the best insurance you have against your DJI battery dying.
Here are all of the things that you can do to ensure that your DJI battery remains in tip-top condition even after a long stint in storage.
These tips come directly from DJI themselves.
Cool dry place
Firstly, you must store your batteries in a cool dry place. Between 22 and 28 degrees Celsius is the best temperature to store your drone batteries for more than a few days.
Also, do not charge your drone batteries when they are hot. Let them cool down after a flight or if you notice that they have elevated in temperature due to storage in hot environments.
Away from direct sunlight
Store your drone batteries away from direct sunlight.
The sensitive lithium polymer composite that is found in most DJI batteries is very sensitive to heat fluctuations. The case of the battery tends to be dark or grey which will absorb the direct sunlight and turn it into quite the hotbox.
Also, direct sunlight can damage the anti-case of the battery causing it to split and become brittle. Ensuring that your batteries fit snugly and securely into your drone will mean that you don’t run the risk of it popping out mid-flight.
No more than 3 months
If you are storing your batteries for more than three months you should charge to 60%. This will be about 3.9 to 4 V per cell and it is important that you keep an eye on individual cell voltage when they are full and drained.
The drone battery is likely to contain multiple lithium polymer cells and they shouldn’t be more than 0.04 apart. If you start noticing some cells holding less voltage than others you may need to replace the battery completely.
Do not over or undercharge
drone batteries take most of the damage between 80 and 100% and at the lower range of 0 to 20%.
Keeping your drone battery in the middle range for as long as possible will extend your battery life. Leaving them constantly at 100% and discharging them to 0% will kill them quicker.
It’s absolutely fine to charge them to 100% before your flight but do not leave them at 100% for many days.
Keeping them on the drone charger for a long period will also degrade the cell battery.
Looking after the charge on the drone battery will extend the life by up to 3 times.
This article is covered everything you need to know about determining whether or not your DJI battery is dead and what you can do about it.
There are plenty of ways to attempt to revive your dead DJI battery that has been proven by the drone community and hobbyists.
Some of them require a little bit more in-depth electrical knowledge but with care and attention, you will be able to revive a drone battery that has been in storage for too long.