(slang) variation of back to
battery, which is an artillery
term. A
gun, after it fires, is said to go out of
battery, which is to say, it recoils. Then after it is
fired it is supposed to go back to
battery, which is sitting the way you see them in photographs. It is used as a
slang term to indicate somebody or something that is now
fixed up; will be all
right for something, or what it has had
wrong will now be over.