Indicates the amount of time, in seconds, that remain until the battery is fully charged.
Even if the time returned is precise to the second, browsers round them to a higher interval (typically to the closest 15 minutes) for privacy reasons.
On return, time is the remaining time in seconds until the
battery, which is a
BatteryManager object, is fully charged, or 0 if the battery is already fully charged. If the battery is currently discharging, this value is