How to convert EddystoneTelemetry.batteryVoltage to batteryLevel

How do you use EddystoneTelemetry.batteryVoltage to determine the batteryLevel or batteryLifeExpectancyInDays?

Truth is, it’s not easy. Battery voltage drops very slowly for a long period of time, and then accelerates when the battery is nearing depletion. For now, we recommend using the battery estimations provided after connecting to an Estimote Beacon.

In that case it seems a shame that Google decided to use batteryVoltage rather than something useful like mAh. Could you not tell us how much power the beacon uses in Watts and we could calculate the mAh ourselves?

The trouble with connecting is that you have to connect, not a speedy or reliable process. Yes it can be done periodically but why the extra work.

We’ll probably come up with a way to estimate remaining lifetime based on voltage in the future updates, so stay tuned for updates.

Other option to retrieve remaining lifetime without connecting is to hit our Cloud API:

In response, we return a prediction of the remaining battery life, based on the last known battery level and beacon’s settings. Not as good as having this in the telemetry packet still, but probably slightly better than having to connect to the beacon.