BAttery Management.

Hi,
For Our project we have a primary battery and secondary battery..
Our requirement is such that primary battery should recharge secondary battery.
Primary battery when drained out system enters low power-mode and is energized from the secondary battery.In low power mode sensor is shut down. Shutdown operation is initiated by system.

I have sketched a small scheme....
i request all of ur suggestions on way to improve the scheme....Please point out mistakes..... and ways to improve.....

Thanks and regards