We are always talking about the manufacture date of tires here but the manufacture date of batteries is never mentioned. It is something that I never gave a thought about until I read this article. I assume this applies to Deep Cycle batteries as well.

I got this from Consumer Reports, Nov. 2012, report on car batteries.

""Get a Fresh Battery" - Batteries lose strength over time, even when sitting on a store shelf. Look for a code printed on the case that uses a letter for the month (A is for January) and a number for the year (12 for 2012). Get one that is less than six months old."

__________________
My Great Wife Joyce
2018 Jayco Jay Flight 21QB
Formerly owned 1705T and 2310H
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Good advice. But don't let Walmart confuse you. Recently bought a boat battery. There was a little circle label stuck on the top of the battery. It was marked something like "06/12". That is NOT when the battery was made. That's when they put it on the store shelf. Like stated you need to look for the date code.
God Bless
Papa