Low Profile Batteries

[OldManMirage]

I am researching batteries in an effort to find some that I can fit in an area above the keel in my Endeavour 32. The space is above the ballast forward of the actual bilge but it is only about 8 inches tall which rules out standard size Group 24, 27 or 31 types.

The boat is built with space for 2 Group 24's in the engine room from the factory and the PO installed 2 more in the quarter berth area, one group 24 and one Group 31. Unfortunately, 2 of the batteries were not holding charge (old) and now I have one Group 24 in the engine room and the Group 31 in the quarter berth !

I don't want batteries in the quarter berth, It's way off centerline and I'd rather have the space for storage. I'll be changing to a pair of new Group 24 wet cell batteries to put in the engine room for the time being. It's inexpensive and will suffice for the next 2 years.

I could go to a setup of multiple smaller batteries. I may do that in order to get the capacity I would like. As said the space is only about 8 inches of clearance, but it's about 18 inches wide and 4 or 5 feet long. That could fit a lot of little batteries, such as the 35AH size or similar. I would leave 1 Group 24 in the engine room as a backup starting battery.

Comparing a set of 12 U1 35ah batteries to a set of 4 Group 31 100AH is not bad. I end up with 420AH at about $900 vs. 400AH at about $750. I could live with that. I'd have to make my own battery enclosure but I'm ok with that too.

I am open to all batteries, flooded, AGM, even lithium although it would be more expensive than I really want. Whatever is out there that would fit. I know that multiple smaller batteries would not be as cost effective as 3 or 4 larger ones. But that is the dilemma.

I welcome all thoughts and proposals, including knowledgeable feedback on my bank of 35AH idea. Thanks in advance.

[GordMay]

East Penn Deka Battery Specifications, including dimensions:
➥ https://www.eastpennmanufacturing.co...Spec-Sheet.pdf

[ranger58sb]

Originally Posted by OldManMirage

I am open to all batteries, flooded, AGM, even lithium although it would be more expensive than I really want. Whatever is out there that would fit. I know that multiple smaller batteries would not be as cost effective as 3 or 4 larger ones. But that is the dilemma.

I welcome all thoughts and proposals, including knowledgeable feedback on my bank of 35AH idea. Thanks in advance.

Maybe AGMs mounted on their sides?

-Chris

[OldManMirage]

Originally Posted by GordMay

East Penn Deka Battery Specifications, including dimensions:
➥ https://www.eastpennmanufacturing.co...Spec-Sheet.pdf

I appreciate this Gord, and I have looked at some spec sheets from similar manufacturers. Unfortunately they are not promising.

The only batteries I can see that would work - other than very common 35AH - are almost impossible to find, and very pricey. I suspect due to their being for very specific applications.

I think the bank of 12 35AH's is looking better all the time.

[OldManMirage]

Originally Posted by ranger58sb

Maybe AGMs mounted on their sides?

-Chris

It's a thought, but I am uncomfortable laying a battery on its side - even when I know it's supposed to be ok.

I think the key phrase is "supposed to be."

[OldManMirage]

I may have to re-think the AGM's on their side. I have researched a bit more and it "seems" they are designed to orient that way if needed ?

I've searched through some of posts on CF.

I may have to make another Thread re-asking that question.

Anyone have opinions on this ?

[donradcliffe]

If you roll your own LiFe batteries from individual 3.2 volt cells, you can put a very large bank in your space. The cells are less expensive than equivalent AGMs, and there are no problems putting them on their sides.

[Bycrick]

My AGM starter battery has been on its side for years without problems. The only orientation restriction that I know of is that your not supposed to mount them with the vents pointed down.

[Orion Jim]

Originally Posted by OldManMirage

I may have to re-think the AGM's on their side. I have researched a bit more and it "seems" they are designed to orient that way if needed ?

I've searched through some of posts on CF.

I may have to make another Thread re-asking that question.

Anyone have opinions on this ?

Mount in any orientation but not upside down. I’m on my third year with a set of group 31 AGM’s. One reserved for starting and a bank of two as my house bank. They are manufactured by East Penn and have a West Marine label on the case. East Penn manufacturers identical batteries and the retailers just put their house brand stickers on the case. I went with the one which had the best price and that was West Marine at the time. Keep this in mind when you are doing your research, find out who the manufacturer is, who cares who the retailer is.
I’ve been very happy with my choice so far. I do suggest you use a quality battery monitor. I have a Victron BMV 702.

[OldManMirage]

I am definitely looking harder at the AGM's. It would be great to hear from others who have mounted them on their side, both good and bad if there is any.

When I look at prices for lithium vs. AGM the AGM still comes out ahead.

Can you mount Lithium on its side ? They seem to be sealed also ?

If I can lay AGM's on their side I could easily fit 4 in the space I have. Amazon has Weize 100AH batteries for $185. Similar brands close to same.

[Pete7]

How about a shelf in the cockpit locker? nice a cool for the batteries. We have just moved ours to under the saloon seats for this reason, even in a chilly UK winter they were getting to 26c in the engine space after a couple of hours motoring.

Also, do you really need 400Ah of capacity on a 32 ft yacht? why not try 2 x 31 and some solar. You can always add another if needed.

Pete

[Bellinghamster]

Paralleling a lot of small batteries isn't ideal. You statistically increase the chance of a shorted cell (because there are more of them) which can cause all sorts of problem, the worst being is thermal runaway.

Consider "telecom" format front-terminal AGM batteries on their sides (Outback energycell 200re or similar). 100AH are about 4" wide, 180AH about 5" wide, 22" long and 11" tall and have terminals on the end. Front terminals make for easy access if they're shoved back in a shelf under the cabin sole. They're not cheap, but have high cycle life and are generally high quality.

[Plumbean]

I have 4 group 31 AGMs mounted on their sides at about a 70 degree angle. Been that way for 12 years (I'm on my second set). Interestingly, I've been doing work on my electrical system and just last week I noticed that the sealant seems to have gathered at the lower ends of the caps over the sealed cells. It looks sort of like a gel that has collected in that area. I've never had any issues, but it does concern me now. So this is a timely topic.

[Plumbean]

Originally Posted by Plumbean

I have 4 group 31 AGMs mounted on their sides at about a 70 degree angle. Been that way for 12 years (I'm on my second set). Interestingly, I've been doing work on my electrical system and just last week I noticed that the sealant seems to have gathered at the lower ends of the caps over the sealed cells. It looks sort of like a gel that has collected in that area. I've never had any issues, but it does concern me now. So this is a timely topic.

Here is what I am talking about. Interestingly, the picture from East Penn of this battery (same as mine but in a Group 27) shows the same asymmetry of the sealant goop being on one side of the caps over the cells. So maybe this is just how they are made?

[OldManMirage]

Pete7, unfortunately I only have 1 cockpit locker and it is also important for engine access. Mounting them low would really impede that access. A shelf would have to be high up on the inside of the hull, a bad place due to balance issues. I don't think you'd want what would amount to a permanent crew member sitting the rail, Lol.

I do have a good solar setup. Ultimately I plan to power a refrigeration unit and a small water maker such as the 3gpm that Pizzazz detailed. And of course there's the usual instruments and autopilot too. I will be upgrading my alternator at some point also.


Bellinghamster, I agree the multiple small vs. few large is not ideal.

Looking for the Outback energycell 200re, it appears to be discontinued. Similar batteries appear pricey.

Also, since I will be making a "battery box/mouting tray" of some sort to fit whatever I end up getting, I think I would prefer to use standard size batteries that are easily available if at all possible. Also good from a cost perspective.

I have been reading on and off all day (in between chores) about AGM's, and I am leaning more and more towards them. Apparently side mounting is one of the reasons they were developed ? I thought I came across that somewhere.

In any case they seem to be a very viable option for me.