The most common and most likely answer to this crossword clue is the 9 letter word RELOADING
I've seen this crossword clue in The Sunday Telegraph
R
E
L
O
A
D
I
N
G
Buddy explains!

The straight part
We know that "charging again" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case charging again = reloading.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RELOADING mean?
RELOADING verb- To load (something) again
- To refresh a copy of a program etc. in memory or of a web page etc. on screen
- To load a gun again; or recharge a used cartridge.
- The act by which something (a gun, a device, etc.) is reloaded; a subsequent loading.