The most common and most likely answer to this crossword clue is the 8 letter word RECHARGE
I've seen this crossword clue in The Times
R
E
C
H
A
R
G
E
More clues leading to the result RECHARGE
- Give more power to troops before onslaught
- Top up Her Grace as needs be
- Once again load up, having moved car here outside front of garage
- Athlete, say, that’s given up injecting heroin boost?
- Give more energy to soldiers’ attack
- Pass on cost of assault by engineers
- Nearly puke, losing heart, with mangled gear – have to regain power
Buddy explains!

The straight part
We know that "Give more power to" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case give more power to = recharge.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 RECHARGE mean?
RECHARGE noun- Water that has percolated from the ground surface to an aquifer.
- The process of charging (an electrical device) again.
- To charge an electric battery after its power has been consumed.
- To invigorate and revitalize one's energy level by removing stressful agents for a period of time.
- To reload a gun with ammunition.
- To add or restore water to an aquifer.
- To request payment again from.
- To charge or accuse in return.
- To attack again or anew.