Battery Puzzle

[Dockhead]

I am in the process of replacing my eight house batteries, and am struggling a bit with the choice of new ones.

My boat was originally equipped with 8 Varta "Hobby" so-called "leisure" batteries (glorified car batts as far as I can tell), arranged in two battery boxes holding four batts each. The house system is 24 volts.

I was happy with the performance of these batteries -- I have a good diesel genset and a good Victron charger/inverter on board, and one generator run in the morning was enough for a worry-free day and night on the hook, without trying to economize. Things should be even better now since I'm installing a wind gennie and have converted nearly all the cabin lights to LED.

But I did not like how easily I killed the previous batteries, nor did I like the fact that I had an apparent melt-down and boil-down while I was off the boat, due to a shorted cell, apparently. It seems to me that all this is a sign of less than robust construction of the Varta "leisure" batts.

And they are not even that cheap -- 110 pounds or about $175 each, which is not much cheaper per AH than some of the Trojans, which seem to me to be "real" batteries.

The problem is that none of the Trojans seem to fit my battery boxes. These are very good -- with forced air ventilation, very strongly mounted, and with strong lock-down lids. I want to keep the boxes.

They each hold 4 Vartas in a row, so the space for batteries is approximately 346 x 688, holding four x 346 x 172 x 239. The only Trojan which might fit would be the 8 volt x 170 amp ones -- I could probably fit three in each box, with a lot of space left over, with 170 ah of nominal capacity per battery box instead of 220 which I had with the Vartas, and at similar cost.

What does anybody think about this?

Another option is to go with the new Lucas XV Supreme. Another "leisure" battery, but much cheaper than the Varta and apparently (?) of higher specification. And, they are exactly the same size as the Varta ones so will perfectly fit my battery boxes.

Opinion?

[stevensuf]

I just replaced my house batteries with elecsol carbon fibre agms, they offer a 7 year warranty, mind you who knows if they will honor them, but i had one in a previous boat i owned and it was well abused and still worked fine, they claim they are good for over 1400 complete discharges , they are expensive approx 400 pounds for a 250ah hour.

it depends on how often you use your boat, i intend to live aboard for a few years extended cruising so the extra performance agms offered outweighed their price, it takes ten percent less energy to recharge them vs normal lead acid.

[stevensuf]

check on fleabay as well, there are some right bargains if you are going for normal leisure batteries, my cousin just got 2 110ah leisure batteries for 110 pounds

[mrm]

Have you considered going the LiFePo route or is the cost prohibitive?

[Dockhead]

Originally Posted by mrm

Have you considered going the LiFePo route or is the cost prohibitive?

I recognize the superiority of this system, but seems to me at this point to be too complicated and too expensive. Some day . . .

[Dockhead]

Originally Posted by stevensuf

I just replaced my house batteries with elecsol carbon fibre agms, they offer a 7 year warranty, mind you who knows if they will honor them, but i had one in a previous boat i owned and it was well abused and still worked fine, they claim they are good for over 1400 complete discharges , they are expensive approx 400 pounds for a 250ah hour.

it depends on how often you use your boat, i intend to live aboard for a few years extended cruising so the extra performance agms offered outweighed their price, it takes ten percent less energy to recharge them vs normal lead acid.

I don't want AGM batteries, for a dozen reasons well articulated here.

But Elecsol make a "carbon fibre leisure battery" in exactly the right size and for the same price as the Vartas. The manufacturer makes incredible performance claims, like 1000 discharges to 80% DOD, and total elimination of sulphation due to the carbon fibers embedded in the plates.

It doesn't sound quite believable, but the claims are backed up by a 5-year warranty -- so maybe worth a try -- nothing to lose, since there is no cost premium.

[Dockhead]

"Q.1 - WHY DO ELECSOL BATTERIES OUT CYCLE FLOODED / SEALED and GEL TYPES?
A. All batteries are manufactured to provide a certain number of deep discharge cycles. The conventional leisure battery should give a cycling life of between 200 - 300 deep discharges. A Gel battery will give between 400 - 500 cycles and an AGM battery 600 - 800 cycles. The Elecsol batteries will give over 1000 deep discharge cycles. Batteries fail in cycling life due to a permanent encapsulation of PbSO4 on the plates (lead sulphation). The capacity loss is more rapid with these battery types, the deeper that the battery is discharged, and the quicker lead sulphation builds up. Upon recharging the battery, not all of this sulphation is converted back to lead (PB0). The result is a gradual loss of capacity.
Another major reason for premature battery failure is due to the oxide shredding from the plate. Standard lead plates are bound only with acrylic and polyester fibres they do not serve as reinforcement of the plate. The cycling life of the Elecsol battery range is much greater than all other battery types because THE CARBON FIBRE ELIMINATES LEAD SULPHATION OF THE PLATES PERMANENTLY. Upon recharging, the original capacity will be replenished. Carbon Fibre acts as a mechanical reinforcement fibre to the lead grid and paste reducing oxide shredding."


Elecsol Batteries - Information Pages - leisure batteries - car battery chargers


Sounds like bullhockey to me. If someone had come up with a technology so revolutionary as to eliminate sulphation, surely we would have heard more about it.

[stevensuf]

All i can say is one was fitted to my last boat, i have no idea how old it was when i got it, it was left uncharged all winter every winter, drained to nothing every time i went out and is still going strong, where as the other 2 leisure batteries i had were dead after 2 seasons.

[yachtsuli]

I am replacing my batteries too. After lots of reading, I have concluded that, in 2012, the correct batteries are either vented wet lead acid or AGM...nothing else. Absolutely do not go for sealed wet lead acid.

You pay more for AGMs. They have a longer cycle life, can be discharged further and can be placed on their side. Like you, I want to keep my battery box, so I have gone for two Rolls 240Ah batteries, lying on their side, in the same battery box.

I recommend you speak to Phil Smith at Barden. They have the best range, and he is a very helpful guy.

Good luck.

[Dockhead]

I have found Trojans in 12v which fit. But they cost double the others, and are the same size and weight as the leisure batteries. I can see that a 6v battery of that size will have much bigger cells and plates and thus will be more robust. But can the 12v version be so much better, to be worth double the cost?

[Dockhead]

I really need to order my new batteries this week, and I continue to be stumped.

I have three major options:

1. El-Cheapo leisure batteries, like the Lucas XV Supreme, which cost about 90 pounds each. On the theory that you're going to kill them anyway sooner or later, so they might as well be disposable.

2. Carbon-fiber Elecsol batteries, which are reasonably price (110 pounds each) and which are guaranteed for five years not to sulphate at all. I combed the 'net and couldn't find anything negative about them, and found quite a bit of positive reviews.

3. 12v Trojans, which cost 200 pounds each (more than $300, so more than $2500 for the 8 which I need -- ouch). This is not that much cheaper than LifePo's. I am also skeptical that they can be so much better than the crappy "leisure" batts, since they are the same size and weight.

Arrrgggghhh. Anybody have any pearls of wisdom???

[goboatingnow]

LiFePO4,

[Dockhead]

Originally Posted by goboatingnow

LiFePO4,

In theory, yes. But sourced from where? Installed by whom? It's complicated and expensive -- not sure I'm ready for that, although in theory it is a totally superior solution.

[SunDevil]

Originally Posted by goboatingnow

LiFePO4,

I am pro-LiFePO4, but my first experience with them hasn't been too good. I don't know if the solar charge controller wasn't set up for them, I needed a battery management system of some sort, or I just got a bad battery, but it died way too fast.

My little system is pretty small, and it is experimental. But, I had expected it to work and I'm still trying to figure out what went wrong.

[goboatingnow]

what happened, generally unless you seriously overcharge or let then fall flat , they are virtually indestructible ( you bring this up on the LifEpo thread??)

Dave