As we previously highlighted, coil cell batteries are usually unsuitable for use with mesh devices. Why? Traditional Bluetooth beacons tend to advertise for about 1 ms every period, where a period is usually configurable from about 100ms to 10 secs. Here’s an oscilloscope trace showing the advertising power of a non-mesh beacon:
The majority of the battery power is used during the 1ms advertising (the peaks in the above trace) and the beacon sleeps the rest of the time using only a few micro amps (uA).
In contrast, in a Bluetooth mesh, the devices are relaying information often and listening for other mesh devices. While we don’t have a trace showing the power use, it would show lots of peaks over time. This imposes a more continual drain on the battery.
It’s for this reason that relay devices tend to need to be mains powered. However, there are exceptions. If data is sent very very infrequently and/or the device is only needed temporarily (e.g. temporary exhibitions) and/or the battery can be made very large, some battery powered scenarios are possible.