Launching your DJI drone into the air for a business photography shoot or just for fun can be a stressful experience if you consider what could happen if the battery were to suddenly fail.
Crashing your aircraft means loss of expensive equipment and loss of business income but the reality is that your success depends on the stable nature of your drone’s battery.
Rechargeable battery dependability can vary in each individual battery, and LiPo (lithium polymer) batteries are no different. That is why DJI developed Intelligent Flight Batteries for all its drones.
Intelligent Flight Batteries are embedded with computer chips that are programmed with specific instructions via firmware to protect your aircraft, extend flight time, communicate data, and protect battery life.
Understanding the function of the firmware is important to the safe operation of your drone.
Let’s delve into all you need to know about DJI Intelligent Flight Batteries and their firmware.
Why do drone batteries need firmware?
Here are the reasons that drone batteries need firmware. I’ll discuss each one in more detail below.
- The firmware programming allows the batteries to have a controlled discharge rate, balancing the power of all the cells within a battery so that one cell does not discharge faster than another.
- Gradual discharge of the battery while in storage.
- When the charging battery is full, it automatically stops the charging so it cannot overcharge and expand with too much power.
- The firmware generates charging error codes.
- Power level indication and low-level warning.
- Communicating with the controller and displaying all the battery information.
- The firmware also activates the automatic RTH (Return to Home) function when the battery has only enough power to make it back to the takeoff location.
Balancing of cells during use
Inside each battery, there are several cells that are connected together to provide the needed voltage. When a battery is in use, these cells give up the energy stored, but in most batteries, the cells can discharge at different rates or speeds.
This can cause fluctuating power levels that may not even be noticed in most devices, but in a drone that is flying up to 400 feet high, a power degradation for even a short time can send the drone crashing to the ground.
DJI firmware sets control perimeters for each cell so that there is no interruption in a steady power source.
Battery storage safety
LiPo batteries can get damaged if they are stored at full capacity for too long a period, so the firmware will gradually discharge the batteries if they are just sitting until the power level reaches about 60%.
This protects the battery life, extending the amount of time your battery can be charged.
Due to the slow discharging, you may detect some heat in the battery when stored. On the Aircraft Battery page on your control screen, you will find an option to pick how long before you want the discharge to start (I will revisit this later).
Control and power levels
Traditional LiPo batteries do not have any way to turn them on or off and no indicators to show how much power they have stored at the moment.
On most devices the on/off switch is on the device that needs the power, not on the battery. The design and programming of Intelligent Batteries have an on/off button and LED indicators.
One of the first things we notice about DJI Intelligent Flight Batteries is that there is a power button to turn them on and off. Give the power button a short push, then a two-second push to turn the battery on.
It provides a positive confirmation that power is being delivered to the drone by flashing the LEDs, then the drone will respond by booting up and giving a beeping signal.
Four LEDs show how much power is in the battery at the moment. When you give the power button a short push the LEDs will show you how much power the battery currently has.
- When the first light is flashing it indicates power is at 20 to 30%.
- The first light on steady shows 30-40% power.
- Two lights steady means you have 50 to 60% power.
- Three lights steady indicate 70 to 80%.
- Four lights steady means 90 to 100% power available.
LED codes while charging
During charging, the LEDs show the charging progress, power level at the moment, when the battery is full and when the charging is over.
A short press of the power button shows the current level of power in the battery.
The LEDs will start to cascade showing the battery is charging and at what level the power is. One blink light shows the lowest power level and four flashing lights show nearly full power.
When the lights stop flashing, that is the indication that the battery is full and has stopped charging.
Charging error codes
The firmware will give error codes when you plug into the charger, showing problem conditions.
- If the second light is blinking twice per second, that indicates that the charger is delivering too much current. Unplug the battery and replace the charger.
- If the second LED is flashing three times a second, this tells you there is a short circuit. The battery needs to be replaced.
- If the third light blinks twice per second the battery is overcharged. This can lead to battery cell damage and you need to discharge some power from the battery by putting into the drone and turning it on.
- If the third LED is flashing three times a second this indicates the charger is delivering too much voltage and you should unplug and replace the charger.
- If the fourth light blinks twice per second it is telling you the battery is too cold to accept a charge, three times per second means the battery is too hot to charge. The batteries need to be between 40 and 104 degrees.
Battery firmware provides for safe flying
When you connect your drone to the controller and all the displays light up on your viewing device (iPhone, Tablet, Smartphone) in the upper right you will see the battery icon.
Select the icon and you will be taken to the Aircraft Battery page. Here you can select any of the options you choose to integrate into your system.
Next to the bottom of the list is a settings button that allows you to select the time a battery is in storage before it starts to slowly discharge. You can select from one to seven days, depending on your need.
For instance, if you had just returned from a flying mission and charged up your batteries, but intend to go out again within a day or so, you won’t want the batteries to start discharging after only a day, but you don’t want them to be at maximum storage for very long.
If a battery is stored either too full or too empty damage may result and the battery will become useless. The firmware program starts a slow, safe discharge at the selected time to bring the battery down to about 60%.
The last item on the list is Devices. Select and you will have on your screen all the details about the battery you have plugged into the drone:
- The serial number
- How many times it has been charged
- The firmware version
- And many other bits of data
This data is being constantly updated by the firmware in the battery and is extremely useful should you have battery failure or some other critical incident and you need to retrieve the data from the battery.
Battery data transmitted to the controller
As you are flying, your view screen will show the current status of your battery, from the amount of power left to the estimated flight.
This is information you need to have to keep flying safely. You can determine how much power drain is occurring in high winds, or when at max vertical climb.
The DJI Intelligent Battery is so smart that as it keeps track of how much power is left, it combines this data with the distance and altitude from where you set the home base, and when the program determines that there is just enough power to make it back, it will cease all operations and fly back to your take-off point.
If, on the way back, the drone meets resistance (winds, etc.) and the battery determines that it will not make it to the Home Point, it will land the drone immediately, avoiding a crash that can cause or destroy your drone.
Updating and installing firmware
Occasionally DJI puts out firmware updates. As technology advances, the IT guys determine that something needs a fix. Usually, they are right on the mark, and these fixes repair glitches, improve security or increase usability.
When it happens, you usually know about it right away because as you start your drone, the control panel tells you, Update Needed, and sometimes won’t even allow you to fly until you update the firmware.
The process is easy to follow and can be found on many YouTube videos in great detail, but here is the short version.
- Remove the drone propellers
- Turn on the drone and the controller and connect them together, using a USB OTG cable from the aircraft to your control screen device by its appropriate cable end.
- Launch your DJI Go app and connect to the aircraft.
- Select the upgrade option and just stand back.
- The upgrade program will download, then will extract the files and begin the upgrade.
- After the screen tells you the upgrade is complete you need to shut down the drone, change batteries and do the upgrade again.
- You will need to repeat this process with each battery till they are all complete.
You can also upgrade the firmware through the DJI Assistant 2 software. Here’s how:
- Connect the aircraft to a personal computer with a USB cable.
- Launch the Assistant 2 and click user login.
- Select your aircraft model then firmware upgrade.
- You may be given a choice of which version of the firmware you want.
- The whole process can take up to 15 minutes. Several indicators may happen and puzzle you, like the gimbal going limp, the drone arm lights starting to flash oddly, and the drone may turn itself off and back on. Just wait patiently until you get the message, Upgrade Complete.
- After that, reboot the aircraft with each of your batteries installed.
DJI Intelligent Battery firmware is probably something you never notice, like having electricity in your home. You just expect the light to come on when you hit the switch, but if the light does not come on you can experience great anxiety.
The same thing applies to the battery firmware. If it wasn’t there we would all know it.