The most common and most likely answer to this crossword clue is the 4 plus 6 letter word FULL CHARGE
I've seen this crossword clue in The Guardian
F
U
L
L
C
H
A
R
G
E
Buddy explains!
The straight part
We know that "Remedy for depleted battery/no reduction in price" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case remedy for depleted battery/no reduction in price = full charge.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.