Green’s Dictionary of Slang

(US) of a man, to have sexual intercourse.

1935		J. Conroy World to Win 253: Why, you cheap sport, said Tess [....] You can’t get your batteries charged for nothing.
1936		Robert Johnson ‘Terraplane Blues’ in Oliver Screening the Blues (1968) 189: Your little generator won’t get the spark, / All in bad condition, you gotta have these batteries charged.
1947		D.W. Hamilton ‘Pacific War Lang.’ in AS XXII:1 Feb. 56: To get your battery charged. To visit a whorehouse.

to masturbate.

1999–2001

quinnelk T. Rex’s Guide to Life 🌐 Okay, since people don’t want to actually say the m-word and the chicken and monkey phrases have been used to death on MTV, I thought it would be my duty to provide you with a bevy of other useful terminology that may be helpful in this area: [...] testing your batteries.