We have recently received a handful of reports from our customers and backers regarding discrepancies in battery levels among their own Firefly units even after a full charge. Please also do bear in mind that different profiles, brightness, operating temperatures will affect the battery life and how fast one unit discharges compared to the other
If this is something you're facing, please do not worry! This is simply because the Firefly unit/App actually measures the battery level by voltage. While it is accurate enough to know how long a unit would roughly last during a ride, it is not as accurate as percentages. This is also why our App has the battery indicator/icon being more of a gauge rather than bars or exact percentage levels.
The main reason for this is that the Firefly units do not come with a specific hardware chip that allows us to indicate the battery levels in percentages (since it would not only add to the overall build cost but also introduce more challenges in terms of design).
To troubleshoot/diagnose if one of your Firefly lights is malfunctioning, it would be best to fully charge all of them and have them set to the same profile/flash pattern and brightness to assess how long they last. That being said, this only works if you have multiple lights and find a discrepancy among them.