"Bart Bervoets" wrote in message
...
I want to charge a 12V lead cell as used in security systems
in my car to use with an inverter.
I want to feed it a constant charge to allow the battery to
be full all the time.
Do i need to build a special charge circuit or will a
diode in front be sufficient to stop reverse flow to my car
battery?

Bart Bervoets


'probably' your best bet would be to install a "DBI" (dual battery
isolator).

this is a solid state device that is basically a bridge rectifier. diodes
steer the charging currents to the batteries and tell the regulator when to
kick in.

IME this works best when the 2 batteries are closely matched as to capacity.