Best yacht battery

[Chae_73]

Worth a read What is a Deep Cycle Battery? - Marine How To

Read through that quite lengthy article; quite interesting although quite a bit of the debunking of marketing seems unsurprising. What I have surmised is:

* Car batteries likely to be ok for many typical boating applications but may not last a huge number of years
* Golf cart batteries are a good alternative and may cost a similar or slightly higher amount initially, likely to last longer so may be cheaper over the life of the batteries
* Don't overpay for a mediocre battery just because it has a label on it saying "marine" and / or "deep cycle".

 

[geem]

Read through that quite lengthy article; quite interesting although quite a bit of the debunking of marketing seems unsurprising. What I have surmised is:

* Car batteries likely to be ok for many typical boating applications but may not last a huge number of years
* Golf cart batteries are a good alternative and may cost a similar or slightly higher amount initially, likely to last longer so may be cheaper over the life of the batteries
* Don't overpay for a mediocre battery just because it has a label on it saying "marine" and / or "deep cycle".

Yep, my take on it as well

 

[BabaYaga]

Yep, my take on it as well

I also read the article and found it interesting. However, it only deals with flooded batteries, so perhaps it is a bit dated in that respect (appears to be written around 2015). I am still curious about the basis for your statement in post #37, that deep cycle AGM batteries is a waste of money. Would you care to expand on that subject? Thanks.

 

[rotrax]

I also read the article and found it interesting. However, it only deals with flooded batteries, so perhaps it is a bit dated in that respect (appears to be written around 2015). I am still curious about the basis for your statement in post #37, that deep cycle AGM batteries is a waste of money. Would you care to expand on that subject? Thanks.

We keep a cheap steel boat in Wellington Harbour, NZ.

4 years ago I replaced the two duff 110AH house batteries with two used deep cycle AGM's bought secondhand from a battery specialist. 100 AH, previously installed in a computer back up inverter system in case of a power cut. By the date code they were seven years old, six of those installed. Now over 10 years old.

The vessel has a 40W solar panel and a cheapo Chinese regulator. The batteries are always up to 12.8v and never require charging. The systems are exercised regularly by a friend who lives aboard a couple of berths away and who looks after it and uses it while we are away.

The deep cycle used AGM's were a third of the cost of new flooded L/A leisure batteries from Burnsco.

Works for me

 

[geem]

I also read the article and found it interesting. However, it only deals with flooded batteries, so perhaps it is a bit dated in that respect (appears to be written around 2015). I am still curious about the basis for your statement in post #37, that deep cycle AGM batteries is a waste of money. Would you care to expand on that subject? Thanks.

You don't need to pay for the AGM aspect of batteries. If you take good quality deep cycle AGM batteries like Lifeline and compare them on cost and life expectancy to say Trojan deep cycle batteries. The Lifeline cost more and have a lower number if cycles. This is pretty typical

 

[[70521]]

I think you're confusing agm with gel, the difference being that gel has silica added to gel the acid. AGMs are usually spill proof (not all are) but the acid will still leak if the case cracks.

P.S. I tried some Classic Enersol AGMs some years ago (waste of time only lasted 3 years) one of which did crack and leak.

I'd be interesting to hear how much acid leaked out and what was done to clean the boat. The link below from a manufacturer, Varta, states that AGMs are more than 'spill proof'. I acknowledge that it is written from an automotive centric view, but it would be extremely unlikely that the manufacturing process was changed just because somebody stuck a label on the outside saying marine.

Gel battery or AGM battery? These are the differences

My current batteries were fitted in February 2020, just before lockdown, while last summer I did not do much this year they stood up to everything from a F0 to F7, from glassy calm to four meter breaking waves. Part of my daily checks is the condition of the batteries, to date I have not seen any damage to the casing. While all materials will fail, and I've done enough destructive testing in my time, I consider that AGMs are for me the ideal battery for fitting on the boat. As @PaulRainbow said above there are different solutions for different uses. It is up to each owner/skipper to make those decisions based on the anticipated use of the vessel.

 

[geem]

I'd be interesting to hear how much acid leaked out and what was done to clean the boat. The link below from a manufacturer, Varta, states that AGMs are more than 'spill proof'. I acknowledge that it is written from an automotive centric view, but it would be extremely unlikely that the manufacturing process was changed just because somebody stuck a label on the outside saying marine.

Gel battery or AGM battery? These are the differences

My current batteries were fitted in February 2020, just before lockdown, while last summer I did not do much this year they stood up to everything from a F0 to F7, from glassy calm to four meter breaking waves. Part of my daily checks is the condition of the batteries, to date I have not seen any damage to the casing. While all materials will fail, and I've done enough destructive testing in my time, I consider that AGMs are for me the ideal battery for fitting on the boat. As @PaulRainbow said above there are different solutions for different uses. It is up to each owner/skipper to make those decisions based on the anticipated use of the vessel.

I accept that we all make our own decisions. No issue there. I have sailed in some pretty nasty weather with my open cell lead acid batteries. Never had a spill or drip of acid leave the batteries. Certainly never had a battery split. Batteries should be mechanically fixed in place in a battery box. If this is the case I can't see why any battery should crack or spill acid. The only way acid would spill is if the boat was upside down. At that point I might have other concerns besides a bit by of acid coming out of the tiny little vent holes.

 

[BabaYaga]

You don't need to pay for the AGM aspect of batteries. If you take good quality deep cycle AGM batteries like Lifeline and compare them on cost and life expectancy to say Trojan deep cycle batteries. The Lifeline cost more and have a lower number if cycles. This is pretty typical

Thanks for your comment.
I am sure Lifeline are very high quality, but they also appear to be very expensive when compared to other DC AGMs available.
Take a look at these two examples of group 24 size batteries, both from the Tayna webshop:
GPL-24T Lifeline AGM Battery
and
Leoch Superior Lead Carbon AGM 93Ah Battery LDC12-90-G24
Lifeline is actually more than twice the price of the Leoch.
Expected cycle life seems to be similar for these two batteries, around 550 cycles when cycled to 80 percent DOD (end of life at 20 percent capacity loss). I do realize the point made in the article that these are lab cycles and also that 80 percent DOD is quite excessive in real life.
I haven't compared the above with the cycle life of Trojan DC batteries, but I am sure a reduction in price of the AGMs by more than 50 percent must have some effect on the cost/benefit calculation?
Furthermore, there are other factors that deserve to be considered. Many boat owners, like myself, have limited space for batteries. The freedom of orientation with AGMs means the space available can house more AHs, which in turn will bring the boat owner more time before charging up is due and/or less deep cycling = longer battery life.

 

[rotrax]

That is true if, in fact, the life expectancy is as expected.

My experience of Lifelines is that they have a very long life, far longer than any expectation I had of their life.

Obviously a good charging regime is required, as well as an 'educated' mindset to battery maintenance.

Overworked our house bank of 4 X 110 AH Lifelines by using one of our large 'fridges as a freezer for 18 weeks this year. Two fridges and one freezer in use 24/7 for all that time, only had shore power for 4 days towards the very end of the trip. Most of the time on the hook or on a mooring. Two hours of charging with the genset each day was almost - but not quite - enough. The addition of 300W Solar for next season should fix it.

Once back in Littlehampton and hooked into shorepower the house bank was quickly back to normal.

 

[Graham376]

I'd be interesting to hear how much acid leaked out and what was done to clean the boat.

The battery I mentioned (one of four Enersol 130s) appeared to have a short on one cell so it bulged and cracked rather than exploding. It was replaced under guarantee but, as the fault occurred when I wasn't on board, no idea how quickly it drained, I suspect with most acid soaked up by the mat, it would most likely have dripped out over time rather than poured, maybe the same as a damp sponge would. Cleaning up wasn't a problem as everything contained in grp battery tray.

 

[geem]

That is true if, in fact, the life expectancy is as expected.

My experience of Lifelines is that they have a very long life, far longer than any expectation I had of their life.

Obviously a good charging regime is required, as well as an 'educated' mindset to battery maintenance.

Overworked our house bank of 4 X 110 AH Lifelines by using one of our large 'fridges as a freezer for 18 weeks this year. Two fridges and one freezer in use 24/7 for all that time, only had shore power for 4 days towards the very end of the trip. Most of the time on the hook or on a mooring. Two hours of charging with the genset each day was almost - but not quite - enough. The addition of 300W Solar for next season should fix it.

Once back in Littlehampton and hooked into shorepower the house bank was quickly back to normal.

Yep and friends with Trojans have abused theirs for most of their life, under charged, forgot to top up electrolyte and still got 8 years out of them in the heat of the Tropics as full-time liveaboards I think that is the benefit of good deep cycle batteries from reputable manufacturers. There are always horror stories as well but on average these batteries from the likes of Trojan and Lifeline perform well. Whether you need to pay extra for AGM is personal choice. For me the cost doesn't stack up and I don't need my domestic bank to be AGM.

 

[12 Year Plan B-)]

A certain outdoor store currently has NUMAX XDC25MF 95Ah AGM batteries on offer for around £87 each... that's about half price compared to the same elsewhere (or similar of different makes).