Moving batteries inboard from cockpit lockers ?

[eebygum]

My two 70A batteries are located in the port and starboard cockpit lockers, is there any safety/fire reasons why I could not move them inboard to improve the weight distribution on the boat, i.e. moving the weight from from relatively higher up (above the waterline) at the back to deeper at the middle (below waterline)

.........reason being the oversized 2gm20 puts a lot of weight at the back. When purchased the boat came with ballast added at the front to get an even waterline ?; I'm now looking to add a Rutland wind genny to the back so simplistically I thought it might make sense to move the batteries to offset. Only risk I can think of is being below the water line any water ingress would pose a more serious threat ?

Any thoughts or is the effect likely to be neglible.

Cheers

 

[hlb]

You can move them where you like. But best as close to engine as possible, cant think why to keep them outside.

 

[Talbot]

Dont forget that the batteries are going to be gassing when they are being charged, and that is not too pleasant a smell (let alone being a tad explosive), also If I remember my chemistry, if you get them immersed in salt water, (unless they are a sealed battery) very nasty things can happen.

 

[hlb]

Rubbish, every boat I've known have the batteries down under the salon by the engines. Come to think of it, even emersed one set in sea water, (slight sinking feeling) Still started engines and were never replaced.

 

[Tisme]

[ QUOTE ]
If I remember my chemistry, if you get them immersed in salt water, (unless they are a sealed battery) very nasty things can happen.

[/ QUOTE ]

If you get so much water in the engine bay that the batteries become submerged then something very nasty has probably already happened!

 

[machurley22]

[ QUOTE ]
If you get so much water in the engine bay that the batteries become submerged then something very nasty has probably already happened!

[/ QUOTE ]
Which might be just the very time you'd want to use the VHF. /forums/images/graemlins/wink.gif

 

[guernseyman]

Don't forget the need to ventilate the batteries for dispersal of hydrogen (small concentration of hydrogen in air forms an explosive mixture - just add a spark), heat, and corrosive or poisonous gases.

 

[Tisme]

I reckon that it will be time to start thinking about flares! /forums/images/graemlins/laugh.gif

 

[William_H]

Very few boat designs seem to be concerned about battery ventilation even with batteries in the cabin area. However you could easily fit a little computer type fan on the engine battery circuit to run when engine is running with a duct to somewhere near outside or the engine compartment. The problem is worst when heavy charging the batteries. I think I would do that in youur case.
Yes it will be well worth moving the batteries forward and down. Certainly the forward position will improve the balance fore and aft. Many yachts sail with too much weight aft. Few of us get the chance to evaluate the balance when sailing with 4 people in the cockpit. They can really drag the transom.
So I recommend move the batteries to under the forward vee berths and fit heavy cable of course to the engine. The lower cofg may also help.
I am currently working on a mate(to convince him) with a 27fter to do the same. regards olewill

 

[Guest]

Normal ....

Thousands of boats over years have had batterys located under bunks in the cabin. Very few have provided increased ventilation for the small amount of gassing that may occur with charging. If you have "smart" charging then you may produce more gas with the boosted levels of charge.

Over-all ..... there is nothing to stop you at all and all I would recc'd is that you make sure a good battery box system is used ... box's can be got in caravan shops to fit most .... these then hold the battery secure, are acid proof and with top to stop any chance of shorts etc. Finally I suggest you have them as close to engine as possible - to reduce cable requirements and voltage drops.

 

[peteandthira]

I am just about to do the same with 4 110s. I am told that they should be sealed type if not properly ventilated otherwise your boat will not comply with RCD safety criteria. I also understand that hydrogen and air doesnt need a spark! Not sure about that one though.

Pops

 

[Guest]

RCD and H + O

Of course all depends on a) does boat have RCD or is it like mine that is built before that piece of paper came to be ?, b) is boat subject to excessive charging and production, collection of Hydrogen gas etc.

As so many boats - like mine are running around with non-sealed Lead-acid batterys under cabin bunks etc. I would say that .... yes it has to be born in mind safety, but if we go overboard on safety - we wouldn't step on a boat in the first place .....

H + O only explodes with outside influence applied under normal circumstances .... otherwise all cars / boats / anything with lead acid batterys would be suspect !!

 

[AlanPound]

Hydrogen and air *would* normally need a spark , however, i) there is typically very little gas produced during charging, and ii) Hydrogen is the lightest gas, and heads for the heavens pretty agressively, so as long as you are not actively trying to contain it, it is unlikely you will get any significant accumulation - simple passive ventilation (vent holes in the top of the box) should be sufficient.