Should All Batteries in Series be Replaced at the Same Time

Question:

When you have two 6v batteries set-up in series, is there a problem if you only replace one of the batteries which is dead and not charging with a new battery? Somebody has advised that you need to replace both at once, but the second original battery is in good condition and charging well. Thanks

asked by: Jeffrey W

Helpful Expert Reply:

It is strongly stated that you should not mix old and new batteries wired in series. Doing so will reduce overall performance and may cause battery leakage or rupture and could also damage the accessories that run off of the batteries as well.

expert reply by: Jameson C