If a drone's battery dies during an operation, the drone will often fall out of the sky and be rendered useless. For this reason, it is crucial to regularly check and maintain the battery health, ensuring the drone remains operational and doesn't become a safety risk.
Start by visually inspecting the battery for any signs of damage or wear. Look for bulges, punctures, or leaks. Damaged batteries should not be used, as they pose safety risks and can lead to poor performance. If there is any physical abnormalities, it's best to replace the battery.
Via the drone's app or smart controller or using a multimeter, battery voltage checker, measure the voltage of the drone battery. Compare the reading with the manufacturer's specified voltage range for the specific battery model. If the voltage is significantly lower than the recommended range, it may indicate a diminished capacity or a faulty battery cell.
To assess the battery's capacity, fully charge it and then discharge it through a flight or using a battery discharger. Take note of the flight time or the discharging duration until the battery voltage reaches the minimum safe threshold. Compare the achieved flight time or discharging duration with the battery's rated capacity. A significant decrease in flight time or discharging duration compared to the rated capacity suggests reduced battery health.
Internal resistance check
Internal resistance is an important parameter that affects a battery's performance. Higher internal resistance leads to reduced power output and shorter flight times. Specialised battery analysers can measure internal resistance, providing valuable insights into the battery's health. If the internal resistance readings are unusually high, it may indicate a degraded battery that should be replaced.
Battery cycle count
Most drone batteries have a limited number of charge cycles before their performance starts to decline. Check the manufacturer's specifications to determine the expected cycle count for the battery model. Some drones and battery management apps provide cycle count information. If the count exceeds the recommended cycle count, it is advisable to consider replacing the battery to maintain optimal performance.
Check for battery errors
If the drone uses a smart battery, the above doesn't need to be done, but it won't hurt to do it as a layer of confirmation.
Most smart batteries will display data in the drone's app. This will often show the cell voltages, cycle count, and display any errors or warnings surrounding the battery. Check to ensure there are no errors or battery warnings in the app. If there are the drone won't take-off until the error is addressed.