A deep cycle of the right capacity will solve the issue ..... he is using a hybrid with just 40amps .
a leccy draws around 50amps as well when running on 10s - we all use deep cycle batteries for them
So why were your deep cycle batteries being destroyed ....... ?
What was the wattage of the winch? ...... Unless it was a high draw winch (1000W plus). ? Was the deep cycle a house battery being charged by the boats motor ? did you run the boats motor when using the winch ? ..... how low was the winch pulling the battery down to ? ...... then was the run long enough to put the charge in .
I destroyed a pair of top notch Odessy 100amp deep cycle AGMS on my old Hornet in about 3 years - because I didn't understand that running them flat wasn't a good thing ...... When I went to a 12 volt leccy - I went with a 200amp AGM which I never flattened & hardly got down to 50% ....... That battery spent 8 years in boats & I still have it today (12 years).
Why don't you think that a deep cycle will fix the issue ?
Chris