Might be worth doing that and disconnecting your terminals.We arrived last week to a flat battery and we borrowed a hire car for a few minutes to jump it but the hire car battery wasn't up to the job so we hired the dam thing for 2 days and bought a new battery back to reus.
P.S.The new battery was 120 euros plus 110 euros for the car plus fuel,tolls and messing about,might be worth buying a spare one over here and take it over in your jeep