Gel Batteries

[PMac456]

A little off topic...but I have 2 8D gell cells...weighing about 150 lbs each...thoughts on alternative set up? Batteries are a bear to replace!! Boat is 92 Hunter Passage 42.

[Pete7]

I created a new thread for you.

What sort of space do you have for alternative batteries?

What sort of usage do you foresee over the next 5 years? weekend and holidays, living on board, crossing an ocean to some tiny island in the Pacific with girls in grass skirts?

How long did the existing batteries last?

What have you got to charge with, solar, wind, shore power or just the engine?

How would you describe you knowledge of charging systems and batteries?

There are lots of choices, is best bang for the buck without spending a huge amount up front going to be your likely option?

Pete

[PMac456]

Two large battery boxes for the current batteries on a rack in engine compartment. Charging is solar, engine and shore power. Current batteries are at 5 years.

Getting ready to retire, so Island hopping down through the Caribbean.

Knowledge on charging systems is limited.

Looking forward to few grass skirts....

Pete

[Pete7]

If you have reasonable access to the top of the batteries, then those golf cart batteries are much easier to handle at 28 kgs and flooded lead acid batteries are a keep it simple (KISS) approach. Our favourite battery Guru will recommend Deka or Penn if Trojan are a bit pricey, but certainly cheaper state side that Europe.

However, they will need watering regularly even with the extra low loss caps. Seem to remember some sort of automatic watering system for Trojan batteries, might be worth googling if access is limited.

https://www.trojanbattery.com/pdf/da...ata_Sheets.pdf

The good news is you can fast charge them with a higher voltage compared to the Gel batteries you have. So worth altering the solar controllers absorption and float voltages. Shame about the Gel batteries, I would have hoped they could have lasted longer.

If you don't have access to the battery tops to add water then we may have to think again, but start with the tape measure to see what will fit.

Final thought, do they get hot in the engine bay? that may need investigating and some work if you want them to last a long time.

Pete

[Boatguy30]

I have been well serviced by 6v gel batteries. Have bought them for 2 different boats at attractive prices $150 per battery for Deka/ East Penn. Going on 5 1/2 years service and batteries are more like 7-8 years old.

Did not do fantastic on pile load test but still showed "acceptable" May need to replace, bur really expect 12-15 yr life

[a64pilot]

Maybe I missed it, did he say his batteries were bad?
Anyway assuming they are, there are sort of two schools of thought on batteries, spend some cash for good ones, which probably means also spending cash on your charging systems, and doing some reading.

Or go cheap and leave things as they are and think of them as consumable items.

Couple of things, a few cheap batteries are actually if you don’t mind watering them, actually pretty good, and some cheap batteries are pretty much junk for deep cycling.
Then any battery will benefit with a sophisticated charging system that charges at exactly the right voltages, is temp compensated, and terminates at the correct time.

So I guess it really depends on how much money your willing to spend and how much time your willing to put into learning.

Most people I run into don’t know squat about batteries and are seemingly constantly replacing them with new West Marine batteries, usually AGM because the guy at the store told them they are the best and they are pretty much always disappointed with them.

Apparently no lead acid battery outlasts a Gel battery, but it seems you need to be careful with charging them. So getting your charging systems set up correctly, maybe staying with Gel is not such a bad idea.

[Dockhead]

I agree with A64 - by far easiest and most practical choice of batts for this application is cheap 6v golf cart batts. Will be nearly drop-in, manage much like how you did the old ones, just that you will need to water them. If the op was happy with the old ones, he'll be happy with these and he won't spend much money or do significant mods to the boat.

Golf cart batts are much harder to kill than gel or AGM, and much cheaper.

I second the tip however to watch the temp in the engine room. No battery likes heat.

If for any reason golf cart batts are not satisfactory, then I would go straight to lithium - more expensive types of lead batteries not worth it. Lithium much more involved requiring significant reconfiguration of the electrical system, but much better in operation and cheaper in the long run if you are off grid a lot and cycle your batteries a lot.

If the OP is in the US, he won't do better than Costco golf cart batts, which I believe are made by Interstate and cost nothing. Trojan T105 is the "premium" option but also reasonable cost.

[noelex 77]

Good quality gel batteries can deliver excellent deep cycle performance.

The best batteries are from Sonnenschein and Hoppecke. They make 12v, 6v and 2v cells. Generally, the lower voltages offer better performance but at a higher cost. Even the 12v batteries can last a long time, 10 years plus with care.

Some of the gel batteries can be mounted on their side so with the myriad of size and voltage options you should be able to find something to fit and the lower voltage batteries are easier to lift.

However, batteries are very expensive to transport so the price varies considerably from country to country. Good quality gel batteries are expensive. I would avoid the cheaper brands. If you not planning on keeping the boat long, flooded batteries will be much cheaper.

[ranger58sb]

Originally Posted by PMac456

A little off topic...but I have 2 8D gell cells...weighing about 150 lbs each...thoughts on alternative set up? Batteries are a bear to replace!! Boat is 92 Hunter Passage 42.

If access and service is easy, six GC2 6V golf cart batteries in series parallel. Should fit in two 8D boxes. You'll also see some capacity increase, roughly 660 Ah versus the ~490 Ah for the 8Ds.

If access and service is not easy, Lifeline makes an AGM version of the GC2s.

-Chris