Batteries 36i

[Andrew Watt]

After reading previous threads on this topic, I have added an extra battery to my SO 36i. Now I have the 3 supplied 70 ah as domestic bank and a new engine battery. I'm not sure on the specs of the Jeanneau supplied batteries but even with 3 X 70ah, the capacity is inadequate for my part of the world (Thailand), especially if you are partial to a cold beer.

My request is for suggestions as to what kind or brand of batteries to replace my current domestic ones with, without too much modification to the existing boxes. Any recommendations will be considered.

Thanks. Andrew

[Zanshin]

Unless you have a good charger, you will be constrained to use the same type of batteries (flooded lead, most likely) which limits the selection somewhat. If you ensure that you never take out more than 50% of your capacity then the brand selection isn't as important as it would otherwise be. But with 210Ah total you only have about 100Ah to play with, and chargin to 100% is inefficient, so realistically you only get about 70Ah (charging to 90% of capacity is 190Ah minus 105 plus "age factor" and Peukert's constant losses in the tropics). That is barely enough for tropical cold beer for a 1-2 day period.
I'd find some space low down that is dry and put in more battery capacity, while it is best to have all same-sized batteries of equal age, just put in 2-3 more 70Ah of the same type. My factory Dryfit 110Ah batteries were sealed ones, do you know what type yours are?

[MartyB]

SOunds like you have what I kno to be size 24 batteries. You can get some up to 85 Ahrs in size. I have an 80 in my boat. Plenty for me....... but then, I do not have a powered fridge, other than ice.

Also, you might find some 6V batteries that are similar in size, but taller that may fit.

You might try this link, not that you can find this brand, but it will give you sizes you can look for
www.interstatebatteries.com/cs_estore/
Go to cehicle on the top clicky line, go down to powersports, then right to marine or RV for types, styles and sizes of deepcycle house type batteries.

Marty

[dublin]

The best solution is to change to gel. They have no memory and can be virtually fully discharged without damage. This gives you a greatly increased practical capacity for the same nominal capacity. When I last checked prices they were not materially more expensive than ordinary flooded.

The make is important. Many Chepstow batteries from the far east and easten europe do not have the Ah claimed. It is important to look at the rating which is determined by the temperature rating of the battery.

Assuming you buy a good battery which is correctly rated at 100ah the difference with gel is as follows. In simple terms a 100ah
flooded battery really only provides 30ah of power whereas a gel gives virtually 100. If fully discharged they can be fully charged again even if left for a long period ( ie two or three months) before being recharged.

I would bite the bullet and replace with gel which effectively gives three times the usage power for the same size

[flippercarson]

I went through the same issue. I have the two cabin version of the boat (not 3). In my boat, in the locker room behind the shower, there is a spot where the floor can be lifted to install two additional house bank batteries making 4 house batteries in total.

This modification lets me get away for 2-3 days without having to charge the batteries.

I started with one extra, but ended up adding the fourth, and only then did I feel I had "enough".

[flightdeck]

Hi Andrew,

A cold beer would be good in your part of the world, don't just cool 1 six pack, nothing kills the electrical system like having a 160L fridge cooling 6 beers only, pack the fridge out with more beer, water, that white foam stuff, anything to help the fridge having less load by filling it.

Cheers

[Andrew Watt]

Thanks for all the advice everyone. I'll have to do some research. I have the 2 cabin version and placed my new engine battery in the space behind the shower as suggested and there is room for another battery in there.
I'll let you know when I make any changes.

[Andrew Watt]

Update.
I replaced the three 70aH as supplied by Jeanneau, with two 6volt golf cart batteries to give about the same capacity. The result was fantastic on a recent 7 day cruise to Ko Chang. I may add two more when I can afford them, but I will have to find space somewhere. The battery compartment needed some modification to fit the higher profile 6v.

[Deleted]

On our SO36i (two cabin) we have replaced the two 70A service batteries with two Trojan 30XHS 130A batteries, which fit in the original box. The 70A start batt has slotted nicely in the well in the port aft locker.
Also fitted a Sunware 69W solar panel on the hatch garage.

Result: excellent - on a three day cruise with 'fridge, A/P, instruments + nav lights on a night passage, during the day the voltage was always >12.6V (ie more amps in than out).

BTW - as per advice above, that big 'fridge was kept well stocked with beer!