Patent ID: 8250398

Claim:
A method performed in an electric vehicle charging station for time synchronization with a Real Time Clock, wherein the electric vehicle charging station does not include a battery-backed Real Time Clock, the method comprising: responsive to booting of the electric vehicle charging station, incrementing a value of an epoch counter which indicates the number of times the electric vehicle charging station has booted, wherein the incremented value indicates the current epoch, and wherein the booting of the electric vehicle charging system creates a boot-up event; beginning a local system clock, wherein the local system clock is not backed up with a battery and will restart once power is lost to the electric vehicle charging station; recording the time of the boot-up event for the current epoch in local system time format, wherein local system time format is not in real time format; requesting real time from one of a charging station network server and a charging station network gateway; responsive to failing to receive the requested real time, performing the following: for each event that occurs on the electric vehicle charging station, including charging session start events and charging session stop events, recording the time of that event in local system time format for the current epoch; and responsive to receiving the requested real time, performing the following: recording the time of receipt of the requested real time in local system time format, synchronizing the local system clock to the real time, converting the time of each event recorded in local system time format to real time format, and communicating each event and its respective time of occurrence in real time format to the charging station network server.