Optima batteries

[LURCHER]

I have two Optima batteries fitted and I think they are coming to the end of their life, they hold charge fine during the summer months when boat is in constant use but now they go flat if left for more than a few weeks.
My dilemma is whether to replace with like for like or do as i have on other boats and put a pair of 110ah tractor batteries that seem to give good service.

[beamishken]

I personally just buy cheap start batteries like the tractor batteries your considering. My thoughts are boat batteries fail through neglect not overuse and I don't think the more expensive ones are immune to this, maybe ok if you nurse them and charge regularly when not In use but I'm not that disciplined so I'd rather use cheaper ones that work the same but don't hurt as much when it comes to replacing them

[Pikey Dave]

Originally Posted by LURCHER

I have two Optima batteries fitted and I think they are coming to the end of their life, they hold charge fine during the summer months when boat is in constant use but now they go flat if left for more than a few weeks.

My dilemma is whether to replace with like for like or do as i have on other boats and put a pair of 110ah tractor batteries that seem to give good service.

The jury's out on expensive v cheap batteries & I don't think there's a definitive answer. It's down to your stance on money & perceived quality. I was let down by a cheap battery which ended up in a rescue due to having divers in the water & not being able to start the engine, never again. I immediately went to a twin optima battery setup, and have done the same on every boat since. Now Poly will point out (correctly) that there's absolutely no relation between the failure of a single battery & the reliability of twin batteries & you can't compare the 2. But for me, it's a case of "I've done what I can", if it goes wrong now I can at least console myself in the thought that I've not cut corners.
I keep my batteries on charge all through the winter & between outings in summer with a Ctek. It might be worth giving yours a reconditioning cycle with a decent charger if you have one, you might recover them to some extent. Also, Optimas are AGM batteries & take a slightly higher charging voltage compared with "ordinary" wet lead acid batteries. There is a "AGM/winter" setting in the Ctek which starts charging at around 15v iirc.
It's your call at the end of the day, I can't advise you, only give you my experiences.

Just for the record, I've had Optimas up to 10 years old that have never missed a beat.

[LURCHER]

Thanks for both replies, much as I thought .
I can’t put on a CTEK as she sits second rack up on drystack .
I will bring both batts home and give them a conditioning charge with CTEK and see how it goes.
I suppose the simple answer is use the boat more!

[The Black Pig]

I have had some good experience with a solar trickle charger, all I believe it does is keep the battery at the level it is without really charging it fully
I do this over the winter and between long periods of unuse
Not sure how this could work on a dry stack

[Pete7]

Lurcher, I suppose the first question is how old are those batteries?

BP suggested solar, well we use a 150w solar panel to keep the house bank charged up. Whilst you probably don't need to go to this length have you got room for say a 40-50w panel. Of course there is now a roaring trade in used rib frames to mount panels on yachts, so second hand frames are in short supply.

Pete

[Iron Dials]

Interesting thread.
I’ve just taken my two blue tops home from the boat.
1 was at 60%, the other was 0%
I’ve put it on a “reconditioning cycle” using a smartcharger (Ring).
It seems ok now but will see in a few weeks.

As for AGM versus lead-acid. I think PD is correct, depends on your point of view. My used boat came with 2 Bluetops so I didn’t choose them, but I like the claimed benfefits (non-spillable, slower self-discharge) and would probably replace like for like as necessary. (I have replaced batt switch and ACR so the dead battery may not have seen any help in a long time)

[GuyC]

I've been looking for a solar powered 'smart' battery charger rather than just a trickle charger for a bit and came across this. It suggests it is suitable for batteries from 2Ah to 240Ah.

I can't vouch for its effectiveness as my boat is in bits in the garage but it seems to fit the bill.

https://www.optimate.co.uk/products/optimate-solar

I tend to subscribe to buying the best / most expensive I can afford and then try and look after them.