Recommended Battery Replacement

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Dan Corcoran
Posts: 48
Joined: Sun Jan 29, 2017 4:32 pm

Recommended Battery Replacement

Post by Dan Corcoran » Thu Mar 01, 2018 1:08 pm

I have 3 large Lifeline AGM batteries, GPL-31T's, that are end of life. Charging system includes what is standard for all of us, the smart regulator, high output alternator, and 2-bank shore charger.

What is the preferred choices for replacing batteries? 3 large batteries? 2 large batteries, 1 starter & 1 house? 2 large house batteries and a small starter battery?

What are the preferred battery chemistry? Firefly, Mastervolt Odyssey TPPL, Lifelife 31T? Lithium Ion anyone?

Has anyone fitted the inch longer Firefly battery into a 109? How did you change the mounting?


Posts: 14
Joined: Mon Sep 22, 2014 9:40 pm

Re: Recommended Battery Replacement

Post by Mvallus » Sat Mar 03, 2018 4:43 pm

Hi Dan,

Replaced our batteries a year ago. We do a variety of overnight races and find having 3 group 31 batteries to last very long (2 house; 1 start). They are so good that we probably could get away with just two. I am uncertain as to whether downgrading to group 27 would be beneficial. What I can say is Trojan AGMs batteries are great. Make sure you set up your charging system correctly for proper chemistry. This is addressed in an earlier post. ... 244-1.html

Phoenix 251

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