The Quanum telemetry system is able to report battery status along with other information to a radio receiver. In this case it’s used in a drone and usefully reports the status of the drones battery to the operators receiver on the ground.
The photo below shows the receiver that displays the remote battery status and the transmitter that goes in the drone.
This little device is old and obsolete but was working up until the point that the LiPo battery in the receiver was connected the wrong way around which was easy to do in this device.
Reversing the battery is never a good idea as in this case it stopped the receiver working from the battery and caused a component to burn out.
The burnt out component was impossible to identify but a look at the datasheet for the chip beside it showed it to be a capacitor fitted directly across the battery. The capacitor had gone short circuit.
Running a LiPo battery into a short circuit isn’t a good idea as they can provide a huge amount of current but nothing bad happened.
Removing the capacitor and powering the device from a current limited bench power supply rather than the battery showed the receiver to still be working so the failed component was replaced. The display on the receiver is looking past its best but is still working well enough.