6 VOLT BATTERIES, MINIMUM VOLTAGE

ktmrfs wrote:

Boon Docker wrote:
Yes, you are killing your batteries.
11.8 is 30% SOC
Should never let the batteries get below 12.1 (50% SOC)

big misconception on never going below 50%SOC. A good rule of thumb for 12V RV/marine but not for a GC2 true deep discharge battery.

Many many many GC2 batteries are speced for hundreds of charge discharge cycles down to 25% SOC. IIRC the common garden variety Trojan T105 is spec'd for 500 charge discharge cycles down to 25% SOC, and they define end of life at something near 75% of spec'd new capacity.

I have two trailers, one a 2004 the other a 2010, both have had GC2's in them they both get 25+ cycles/year down to near 25% SOC and the 2004 I replaced the batteries and passed them to a friend at 10 years, he got a few more year out of them. the 2010 trailer still has the original batteries. So far I have run 3 sets of GC2's each with 250+ charge discharge cycles to 25%SOC plus many to around 50% and still were meeting my needs. The important thing is do NOT leave them discharged for more than a few days, get them FULLY charged (and that means do NOT rely on the common WFCO charger in trailers it will NEVER get them fully charged)

Not to the OP, get a good battery monitor that will measure actual discharge/charge amp hours, don't rely on battery voltage to determine an accurate state of charge.

it is and it isn't yes there spected down there and that draw is what there life is based on, but by keeping it above 50% when using them you can extend there life. thats where this is comining from, to get the most ife out of them. for example I had four 240Ah GC batteries in my 5th wheel that I justy replaced after 13 years. going down to 20 or 24 or 30% I would have never got that life out of them, maybe 5 years if I was luckey.

Steve