You can have two 12v batteries in series, and to charge them go to a camper supply store and buy an isolator. You will have to rig up the switching to go from charge mode to wheelchair hoist operation mode so that you won't burn out the alternator. (The two processes must operate independently.) This is the best way to go on this, rather than to try to modify the hoist mechanizm.
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You can have two 12v batteries in series, and to charge them go to a camper supply store and buy an isolator. You will have to rig up the switching to go from charge mode to wheelchair hoist operation mode so that you won't burn out the alternator. (The two processes must operate independently.) This is the best way to go on this, rather than to try to modify the hoist mechanizm.