Compact engine and house battery recommendations please

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picardy

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I am looking for the most compact way of installing 2 x batteries in my new Woden motor launch which is currently in build.

Engine is a 21hp and will likely have a 60 AH battery and I also need a 110-130ah house battery for fridge, instruments etc etc.

Space is very limited and am looking to find the smallest battery range (narrow and tall is better than lower and broader. What are my options, cost is not the primary driver here - space is my main issue!

I am happy to have any type that is suitable (eg lead acid, AGM, GEL, Lithium)

Thanks in advance
 
Red Flash 1100 for engine start and AGM or FLA of your choice that fits the space for the house. choice between types will depend on how much use you make of the house and how long you want it to last. The big advantage of the Red Flash is that it can be mounted in any orientation and is roughly half the volume of an FLA start battery. Make sure you have a good split charging system so that the engine start gets priority. The Red Flash in my Morgan is now 118 years old and just has a trickle charger when left for more than a month. on a boat a solar panel will do this easily if you don't have access to shore power..
 
My simple answer always is to visit an RV / Caravan Dealer / Shop.

Discussion of what you have and what you want usually ends up with a good result and kind on the pocket. They deal with this sort of question every day ......
 
Refueler said:
My simple answer always is to visit an RV / Caravan Dealer / Shop.

Discussion of what you have and what you want usually ends up with a good result and kind on the pocket. They deal with this sort of question every day ......
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Why would you want to do that? What do they know about batteries for boats? RVs etc choose batteries for their requirements out of the same range as boats and pay the same price for the same battery if that is what is chosen. As it happens the requirements of RVs etc are similar in many respects to those of a cruising boat so actually might use the same mix of batteries.

Engine start battery (although smaller for a 21hp diesel than a typical RV engine) and a domestic equipment of size and type appropriate to the expected pattern of usage - and budget!

See post#4 OP says space limited, therefore Red Flash (or Odyssey) as very small and powerful specifically for engine start - and commonly used on RV and particularly emergency vehicles such as ambulances. Then an FLA or AGM of biggest capacity to fit the space available. Cheap FLA, but shorter life or more expensive AGM for longer life. Many are happy with, say a 5 year life of relatively light use from a £100 FLA, others prefer to spend approx 50% more for potentially double the life with an AGM (plus quicker recharge and lower self discharge).
 
Tranona said:
Why would you want to do that? What do they know about batteries for boats? RVs etc choose batteries for their requirements out of the same range as boats and pay the same price for the same battery if that is what is chosen. As it happens the requirements of RVs etc are similar in many respects to those of a cruising boat so actually might use the same mix of batteries.

Engine start battery (although smaller for a 21hp diesel than a typical RV engine) and a domestic equipment of size and type appropriate to the expected pattern of usage - and budget!

See post#4 OP says space limited, therefore Red Flash (or Odyssey) as very small and powerful specifically for engine start - and commonly used on RV and particularly emergency vehicles such as ambulances. Then an FLA or AGM of biggest capacity to fit the space available. Cheap FLA, but shorter life or more expensive AGM for longer life. Many are happy with, say a 5 year life of relatively light use from a £100 FLA, others prefer to spend approx 50% more for potentially double the life with an AGM (plus quicker recharge and lower self discharge).
Click to expand...

I would then gather from your reply that you have rarely been to an RV / caravan dealers ..... too often what is priced X at a Chandlers and other Factors is same but cheaper at caravan dealers ...........

Second - Chandlers and other Factors are usually versed in many other matters but often poor on battery forms and use ... but caravan dealers have this matter every day ...

Why you post such a put down - fails me ...
 
Another vote for Red Flash for engine start and a vote against LiFePO4 for your application. I'd be inclined to explore lead carbon, which has good energy density, for your house battery.
 
Poey50 said:
Another vote for Red Flash for engine start and a vote against LiFePO4 for your application. I'd be inclined to explore lead carbon, which has good energy density, for your house battery.
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+1.
I replaced my house bank last year, 3x90 Ah, Leoch DC lead carbon.
The size of box is, from memory, 24 something, the same size that would normally hold 75 or 80 Ah.
 
I have found oddessy batteries very good over the years. Some of the rolls range are quite tall rather than broad so they might be worth a look.
 
Refueler said:
I would then gather from your reply that you have rarely been to an RV / caravan dealers ..... too often what is priced X at a Chandlers and other Factors is same but cheaper at caravan dealers ...........

Second - Chandlers and other Factors are usually versed in many other matters but often poor on battery forms and use ... but caravan dealers have this matter every day ...

Why you post such a put down - fails me ...
Click to expand...

Sorry you see it as a put down, not intended but you do tend to respond by directing people to caravan and RV dealers and although for some products these can be a good source, I am afraid that is not so for batteries.

You don't have to buy batteries from chandlers - indeed in my experience most chandlers in the UK do not even bother selling batteries. Force 4 do not even offer FLA or AGMs - only Lithium, presumably trying to capture the early adopters. They don't bother because they simply cannot compete with specialist battery suppliers.

There are loads of on line suppliers and absolutely no reason why you would get any better prices from a caravan or RV dealer. The sort of batteries suggested are not "marine" but generic batteries used in a wide variety of applications. Neither should you need to use the so called "expertise" of caravan dealers in choosing your batteries. The web is full of information on the subject - and you can even get good advice by asking the question on forums such as PBO.

There is nothing unusual about the OPs requirements which are very simple and straightforward. There are 2 approaches I suggested, one a low cost and the other more expensive but longer life. In fact his requirements are exactly the same as for my old boat and when I intended to keep the boat in 1992 I went the expensive route of a Red Flash and a mid price AGM. Later (many years) when those batteries were past it and I intended to sell the boat I went cheap with a small car type start battery and and a smaller capacity house because of the space limitations - both own brand from my local distributor depot. First set up would today cost about £360 with a house capacity of 115Ah and the second £170, but only 95Ah because of space issues. In the type of use I would give it the first would probably last 3 times as long as the second. Once that choice is made a few minutes on Google and you can order the batteries for the next day delivery.
 
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