Battery Position

[Nunfa1]

Hi all, finally agreed a deal and put down a deposit on a Kingfisher 20+. It's a little scruffy but should be ready to sail, having it checked over next week before completing the sale.
I cant find any evidence of where a leisure battery would've been mounted, it had one at some point because the switch panel is still in the head but the previous owner didn't have one fitted.
As I'm starting from scratch, where is the preferred position for a battery? I'm guessing somewhere in the cockpit lockers fed to a distribution box in the cabin fitted with a battery isolator.
AS usual, any advice gratefully received.

 

[Binman]

My battery is housed under the step down into the cabin, but anywhere that is quickly accessible and secure. Not in fuel locker. Needs to lay flat. I have a small fire extinguisher next to mine, you will require 2 or 3 of these plus fire blanket as well,

 

[johnphilip]

A 20' yacht will be quite sensitive to trim. Even with 2 or 3 adults in the cockpit the bow is going to start to rise up I would not add to the weight aft but see if the battery could fit under a saloon berth. Placed here the weight is forward and also much lower. There are batteries with an overall height just under 200mm even up to 110 amp hour which should be plenty. In fact I would probably go smaller. I don't expect you have a fridge and without one power usage is far far lower.

 

[VicS]

I'd have thought somewhere in the midships area to keep the weight central. That would also be logically close to a switch panel in the head, although I imagine you intend relocating that . In a small boat you also have to consider balancing the weight athwartships by stowing heavy items, the beer and other stores for example, on the opposite side.

My own battery is located in one of the under berth lockers immediately forward of the main bulk head, which is where the original building instructions suggested. It does limit the size to 70 Ah though.

If OTOH you have an electric start engine close to the engine would be logical.

You will need a battery isolator (and fuse) as close as possible to the battery..........Quick disconnecting battery connectors might be an alternative to the isolator but you may then need a battery with dual terminals if you have permanently connected items such a solar panel

 

[Nunfa1]

Thanks guys, I hadn't considered the weight. There are a number of options midship that I can consider.
This boat owning journey is going to be a steep learning curve and this forum is going to be invaluable.

 

[johnalison]

Low is best, but needs to be in a sealed compartment in case of flooding, when you may lose your GPS etc.

 

[ghostlymoron]

Don't forget that batteries are heavy mothers so put them somewhere you can lift them with straight back. I've just bought a 88ah Hankook from battery megastore. This would probably be suitable for you too.

 

[William_H]

I would suggest you start using your new 20ft boat for a bit before you make any permanent decisions on battery. Much depends on your leectrical power needs. Will you sail at night? Will you run a VHF 25w radio on receive all the time? How will you recharge the battery. You may well find that the most convenient thing to do is take the battery home for recharge after each outing. This means you need a light weight battery. Even 10 NiMH D cells in a plastic box can work well.
As said for a heavy battery trim is your most important factor. This will depend on how many people you usually sail with. If you carry 3 or 4 people in cockpit you will want the battery as far forward as possible. (especially if you have an outboard engine ona transom bracket.)
Best approach is to go sailing once you have got into the swing of using the boat. Get someone to photograph the boat from the side, you will soon see how the fore and aft trim looks. My guess is that it will be stern heavy. Ideally the flat area of the hull at the transom should be near water level. ie not dragging the transom in the water . good luck olewill

 

[[70521]]

Last winter I moved both batteries from the cockpit locker as:

• They might get wet;
• They were difficult to access;
• There was miles of wire;
• They were on the same side as the fuel tank; and
• Taking a voltmeter reading was awkward

They now they live under the quarter berth on the other side to where they were:

• If they get wet we are in deep do do;
• Access is easy;
• The wiring has been reduced by 75%;
• They are on the opposite side to the fuel tank and should improve the balance; and
• Taking a voltmeter reading is easy.

I replaced my ancient 85Ah house battery with a 230Ah one at about double the cost. While in another posting I've been told that as it has a high cold cranking amps rating it would be useless, but as I am not planning to cross the Southern Ocean in this boat I am not duly concerned.

 

[Daydream believer]

I've just bought a 88ah Hankook from battery megastore. This would probably be suitable for you too.

No possibly not. The wires would not reach from your boat to his