Software

Hi all, Did some searching in the forums but couldn't seem to find an answer around this. Does anyone know if the value of the remaining battery capacity is accessible somewhere? I've gotten Bittle connected to AWS IoT Core with the ESP8266 module and would like to periodically send messages containing the remaining battery capacity (amongst other data) to use in a web application I'm building for a fleet of connected Bittles. I'm trying to use this value to add functionality to send a notification when a Bittle's battery is running low. Anyone know where I could find guidance around this? Thanks!