The electric winch handle batteries have great autonomy, enough to sail a day without a problem.
 
Example of use on a 40 feet sailboat with a 15 knots wind:
Hoist 3 times the main sail
Tack 30 times
Charging time: 1 hr. 30 min. (12V and 220V)
 
For sailboats bigger than 45 feet, we recommend having a spare battery.