Advise/opinions: battery relocation.

[NYSail]

Good morning all!

So based on advise from Maine Sail I would like to relocated my house battery bank. Beneteau place the house within the engine compartment which obviously gets hot regardless of the exhaust blowers built in to this space. Currently I have two 4D agms however wish to ditch these for maybe 5 group 31's so I don't have the task of lugging 150 pounds each worth of lead when they need to be changed. The current location is ideal in regards to being low and center in the boat. My best option would be my port lazerett. I will be able to get 5 group 31's in this space with no problem and still have plenty of room for additional storage. This puts the weight 8 feet aft and 4 feet higher than the current location. Also this could help off-set the fact that I have a 350 lb genset located in the starboard lazerett, however the genset is 4 feet lower and slightly aft of where potential new location would be. The boat does have a slight list to the starboard by design and is accented by the genset. Regarding wiring, the lazerett is just above the current battery switches so no real difference in distance and an easy wire run. Also I recently added 100 feet (160lbs) of chain in bow with 55lb anchor.

So I guess my question would be do you think this would alter / change drastically the performance of the boat? We are cruisers that like nice performance.

Attached are a couple of photos....
Thanks!
Current

Proposed

 

[dlochner]

Why go with 5 Group 31s, when 6 GCs would provide roughly the same capacity, be easier to move, and perhaps take up less space?

 

[Gunni]

We have similar boats. I looked at that space but 1) I would rather have that space close to the helm for my dock lines, and because it is a drained locker I can keep nasties like acetone, antifreeze and solvents in there.
In addition I judged that location too far aft and too high - way above the waterline and way off the centerline. My boat had a stern squat, yours likely does too since there is so much stowage aft. That messes with the boat's ability to point. So instead I put 4 group31 AGMs where my old 3000W inverter had been installed - in a saloon settee cabinet 3 feet from the keel and below the waterline, midships. The wiring was straightforward using the old inverter cables and the location is cooler (better battery acceptance). That is almost 500ah of juice.

 

[Benny17441]

Like you said the current location is ideal and so thought the boat's designer. Hot air rises and you indicate having exhaust blowers so them batteries may not get as hot as you fear. Check their actual temperature and verify with the batteries manufacturer the acceptable range of their operating temperature. Not saying that keeping them cooler would not be beneficial but the alternative of relocating could be less attractive. It is correct that keeping batteries cooler will be beneficial to them but we cannot concentrate on one component and disregard the negative aspects of a modification. In my book just the ease of access alone would greatly influence the chosen location. I have seen a set of batteries sit on a boat's cabin for a couple of months because the owner could not muster the motivation to get them into a difficult to reach location. Convenience has a value.

 

[Don S/V ILLusion]

Unless you do a lot of motoring, these arguments about moving batteries to a location away from the engine because of temperature is a largely academic one. if you are like most people who use your boat recreationally and motor as little as practicable, the issue is trivial especially when considering most power boat batteries are co-located