Life expectancy of service batteries

[JustinC]

Our 2 service batteries have gone past the 5 year mark and are starting to hold their charge for less time, is this normal? Should I just identify and replace the tired one or bite the bullet and change both?

Any recommendations on specific brands or types?

Thanks

 

[Richard10002]

My cheapest of the cheap, (£70 each for 3 x 110Ah Open Lead Acid), lasted a year, and I'm pretty anal about charging and monitoring.

Almost replaced them with 4 x Trojan T105s for 450Ah @ 12V but, due to space restrictions, I ended up buying 3 x Varta Hobby Leisure A28 at £100 each. So far so good, but I've only had them 2 weeks.

 

[vyv_cox]

I find 4-5 years is about normal, used heavily for half the year, kept fully charged for the other half with solar power. I don't think the expense of AGMs and top end types is justified but others will always disagree.

 

[charles_reed]

My 120AH open lead acid battery, forward, lasts between 7-10 years - it's only used for services. The sealed lead-acid, each 95-105AH which alternate as engine start batteries and run the fridge compressor between 4-5 years. Whether this is a function of the relative battery construction or the work they have to do I hesitate to pronounce upon.
I agree totally with Vyv about the lack of benefit of sophisticated batteries - in fact I've found that the cruder the battery construction the greater the correlation with length of life.
If I could find open batteries to fit the exiguous boxes for the two aft batteries I would use those rather than sealed lead acid.
The boat is in use 6/12 of the year - has a 20 amp switch-mode charger (used infrequently, but for long periods, as I'm usually @ anchor), an Adverc external regulator and 328 watts of PV panel @ 24v through an MPPT controller.
My target price for replacement batteries is about €0.80/AH.
Lead-calcium batteries appear to have a longer life than lead-antimony but appear to suffer the disadvantage of being slow to re-charge and to be reluctant to supply power.

 

[jimbaerselman]

I assume your "service" batteries were "leisure" type (a limited number of robust plates designed to give relatively small currents for a long time and a long life) rather than "starter" type (a large number of plates designed to occasionally deliver very high currents for short periods)

Service battery life is dependent on how deeply and how often they are discharged; and how throughly they are recharged. If you never allow discharge below 50%, and regularly re-charge thoroughly, even 10 years life is feasible. However, this is ideal, only achievable with good monitoring and control. More likely is 5 years.

I agree with value for money best achieved with open lead acid. But keep them topped up!

Usually best to change both . . .

 

[sarabande]

I concur with JB that battery banks should consist, for reasons of charging efficiency and battery life, of units of the same type and capacity.

5 years is not over long but it depends on the original specification and regime of use/charging.

Having recently bought a couple of AGM Optimas, I am impressed by their construction, design, and the feedback from users about how hard they can be driven. Bought through the forum, they were no more expensive than medium-quality lead acids.

 

[geem]

My cheap caravan leisure batteries were sealed type and never went near the 50% minimum charge due to lots of solar, efficient fridge, led lighting everywhere. They were 85 amp/hour each in a bank of 4. They cost £45 each seven years ago. Still going strong when I sold the boat end of last year.

 

[sailaboutvic]

Mind have so far last 4 years and still going strong , just acid fill type .

Www.dufour385.webs.com

 

[mocruising]

We got 7 years out of our last batch of four (2 x series 2 x parallel) open 12 v non sophistigated house batteries and the same out of our 12 v engine start and 12 volt service for var nav. gear. We always buy Bosch or Varta and this time went for the sealed type some are three years old now we shall see. I am pretty anal about keeping them charged up too.

 

[cmedsailor]

I have just replaced two Delkor DC31 used for services and never discharged more than 50%. Both were 5 years old.

 

[KellysEye]

We were using house batteries 18 hours x 365 and they lasted five years, they were two Trojan T105 6v in series.