I believe that you will find that a lot of the batteries are going to have a 12 to 18 month warranty. That is what I found looking for a replacement this last year. Had found most were 12 month free replacement or if 24 months they were prorated. This was for normal lead acid batteries.
2014 Coachmen Pursuit 31BDP
2016 Ford C-Max Energi
1987 Chrysler LeBaron Convertible
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