What the OP posted was a monitor. It has nothing to do with putting amps back in the battery. You set the Minder for what ever low voltage you want, say 10.5 the when the battery drops down to that the alarm will function. It will also give you a reading of how many volts are being supplied to the battery or system.
I have been using one for the battery I have mounted in the engine compartment of my truck. That battery is on a separate system then my house battery,s and not connected to my Trimetric.
When I use it I can look through the pass through window and I can determine if the battery has dropped below the set voltage.