Help: 12 volt Automatic cut off circuit

Hello,
I want to built a UPS system for 12 volt devices use only use current 12 volt and no need to have an inverter from 220 volt to avoid waste of energey because a wall charger of 12 volt and an 12 volt battery is enough like in the picture:



Please can you help me to get this automatic cut off circuit, which I wish to fulfill the following:

1- Automatic detect if there is a battery connected or not, i.e automatic cutt off when there is no battery

2- Automatic cut off to avoid over charging when the battery is full charged.

3- Have 2 Leds, one green detect that the circuit is cut and the battery is full. The other red indicate that the circuit is on and the battery is not full.

4- Automatic connect on the circuit when the battery is lost a part of charge for any reason.

I hope you can help me.

Thanks alot

There is no need for the change over relay and the parallel connection. You can just run the Router from the battery at all times, and have the charger supplying the battery. It will be the same result but be simpler and easier.

If you want a battery charge controller with a display, this one will work but it is a little more complex than the "2 LED" system you asked for; It has a LCD and you can set the exact battery voltage, both the setpoint voltage AND actual battery voltage are shown on the LCD.
See the SH1_Charge project on this page; Shift1-LCD Projects

Thanks. The Shift1-LCD with PIC option need to be programmed.
Where can I get this one programed for SH1_Charge ?
I want one fully programmed and ready to use.

24v 7.2Amp. battery charger cut off circuit

Plz. can any one will help me to designe the 24v 7.2Amp. battery charger cut off circuit
this should be low cost means simple.
refer my e-id: namdeo_gaikwad@yahoo.co.in