Which Battery

[Maxidom]

We have two 85 amp hour Sowester Marine deep cycle batteries which need replacing on the domestic circuit of our Maxi 1000 (powered by a Volvo 2020). We can replace them with similar batteries at £42 each but On Board Power at Hamble tell me that fitting two Squadron Marine AGM 85 amp hour batteries at £90 each is my best option. We will be cruising Biscay this summer and with a five day crossing in mind which domestic batteries would you wise people out there suggest we consider. I must add that the battery compartment was designed with the smaller sized battereis in mind.

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[tony_brighton]

If you know you are doing a long crossing I'd have thought the extra capacity would make sense.

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[Paulka]

No reason to pay twice the price for the same capacity!
The "super thingy" probably will not last longer than the cheap ones.
Then, what's the point?

Have a nice crossing.

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[dickh]

How long have the old batteries lasted? If the AGM ones are guaranteed to last more than twice as long then they will be worth it, but I doubt it, and would go for the cheaper replacements.
You say the battery compartment was designed with the smaller battery in mind - but is it possible to enlarge it to take say a couple of 110ah batteries? if so this may be the best route to go. If not possible, search around and see if anyone makes a larger capacity battery but the same physical size.
Good luck on your trip.

<hr width=100% size=1>dickh
I'd rather be sailing... /forums/images/icons/smile.gif

 

[byron]

<font color=blue>Go to your local battery/tyre/exhaust shoppe. You will get deep discharge 110 amp batteries for around £46 each.
I recently changed 3 of mine and got the ones that you don't even have to check the water on for that money.

<hr width=100% size=1>http://www.alexander-advertising.co.uk

 

[ccscott49]

Agree with Byron on this one, also the chap who said, will the expensive ones last twice as long as the cheap ones? if not, whats the point of expensive ones. Think about an alternator smart regulator aswell.

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[Evadne]

I would advise you go for the cheaper option. As you will have read in numerous articles over the last year, the difference between a "Deep Cycle Marine" lead acid and a bog-standard car battery of the same capacity is not as huge as the cost difference. If you really deep-cycle a lead acid, regardless of its construction (down to say, 25-50% of its capacity) then battery life is frighteningly short regardless of what you use. The chemistry is very simple and battery life is down to the quality of the plating which isn't necessarily proportional to the cost. The best way to keep a battery running is to keep it charged.

If you keep it topped up and rarely run electrics without some sort of charging (i.e. typical coastal cruising scenario) then a car battery will do you fine. I've used one for the last 18 years with only one change due to an accidental total discharge.

Blue water cruising (i.e running electrics while sailing with some auxhillary charging) is between the two and I would go for the biggest battery I could fit, and if a caravan Deep cycle is half the price of a Marine one then that would be the one to choose. Experience is everything here, but not as important as a battery-friendly charging regime. A low-quality battery, well looked-after, will last better than an expensive one, neglected. Like lots of things, now I come to think of it....

yours,

Chalky


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[Maxidom]

Thanks everyone - some things to ponder on. I personally like the idea of fitting 2 x 110 amp hour batteries and may try and fit a second battery box near the main battery box. A smart charger or adverc sounds a good investment. Thanks

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[colvic]

An Adverc charging system and four car batteries of 75amp have kept us running for almost 4 years as liveaboards. Sealed to be maintance free, they survived being under water for over an hour and are stil working perfectly.

The "smart charger" is the thing to aim for.

Phil

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[Jools_of_Top_Cat]

I have fitted last year two elecsol batteries 125Ah deep discharge and starter as they are carbon re-enforced. This meant not having to carry a further two standard starter batteries.


They are a British company in North Wales and I have no connection but have been very pleased with their product. <A target="_blank" HREF=http://www.elecsol.com/>elecsol website</A>


<hr width=100% size=1><font color=blue> Julian </font color=blue>

<A target="_blank" HREF=http://www.ukstaffords.com>http://www.ukstaffords.com</A>

 

[Chris_Robb]

the advantage of cheap batteries is that you can charge them hard - let them gas a bit, and refill them with water. Low maintenance batteries cannot be refilled with water, I believe, if over cooked perhaps by accident

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[bedouin]

That's my philosophy too. Just bought two new 110AH "Heavy Duty" batteries for £49 a piece. These can be charged hard at 14.8V and topped up with water if I boil too much off.

Posher batteries would cost almost twice as much and couldn't be charged as hard, so would require more use of the engine.

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[tr7v8]

100Ahish will always be the cheapest battery in terms of Ah per £ apparently as it ist is sold in the largest quantity. £ 49 seems a damn good price even though.

<hr width=100% size=1>Jim

Draco 2500

 

[qsiv]

Letting them gas a bit...

I'd just say be a liitle careful of the hydrogen build up. We have a blower fan that pressurises the battery boxes, and a vent that allows the slight pressure to ease the gas overboard. as I recall the blower cuts in automatically based on battery temperature. The rationale behind pushing with the blower rather than sucking<g> is to ensure that the hydrogen never passes over an active, sparking dc motor. Dutch attention to detail is quite worrying sometimes.... even if they dont line the curf on screwheads up like English builders do.

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