To use Standby mode, the dashcam must be connected to a constant power source. See Hardwire the dashcam to the vehicle fuse box for more details.
When the Standby mode is entered and when it is exited, a relevant event is triggered and sent to the cloud. Read here for more information about these events.
While in Standby mode, you can retrieve recordings from the dashcam. In Standby mode, the dashcam draws a current of 34 mA.
For power consumption details see A1-12 specifcations.
To assess battery life, use this formula:
Battery Capacity (mAh) ÷ Load Current (mAh)