SelfSyncBattery message
Battery messages store the charge level of the device over time.
Fields
timestampDateTimeMoment the message refers to, in UTC. FIT stores it as seconds since the FIT epoch (December 31, 1989, 00:00:00 UTC); decoders usually expose it as a regular date.
Battery level.
mesgNumStringGlobal message number identifying the kind of message. Decoders use it to know which profile to apply to the data.