ErikKiekens
New member
Again somebody tries to convince me that car batteries (much cheaper) work just as well as marine batteries. What was the story again?
Erik
Erik
car battery on a boat
- Thread starter ErikKiekens
- Start date
GrahamM376
New member
They work well as starter batteries but not for longer low current draws as with domestic loads.
ghostlymoron
Well-known member
Most people use a car battery for starting the engine but use a Leisure type to power their lights, instruments and other auxiliary's. The starter battery is recharged in a few minutes so doesn't need to be anything special. The Leisure battery needs more careful management to avoid ruining it.
boatmike
Well-known member
Batteries are either designed as "cranking" batteries where they need to pump out high amps for short periods or "service" batteries that are designed to give lower outputs for longer periods like a disability scooter or golf cart. Car batteries are cranking type and don't serve well as service batteries on a boat but as others have said are fine as engine start batteries. Then there are hybrids sold as "leisure" batteries which arguably do both and are still relatively cheap. Basically all will work but not as well as batteries designed for a specific job.
VicS
Well-known member
Leisure batteries are only modified starter batteries..... In some cases I suspect the modification is little more than a different label 
lw395
Well-known member
Main problem with car batteries tends to be they are not big enough.
One of my boats came with two truck batteries which did very well as house batteries.
One of my boats came with two truck batteries which did very well as house batteries.
skipmac
Well-known member
Leisure batteries are only modified starter batteries..... In some cases I suspect the modification is little more than a different label
I have seen comments to that effect before. Is that the case with all batteries called leisure batteries or just some? That isn't a term used on this side of the pond but there are batteries sold as "marine" or "dual purpose" starting and domestic use that are certainly starting batteries that may or may not be slightly modified.
Not sure if this is an option in the UK but in the states by far the best bang for the buck in true, deep cycle batteries are the 6V batteries used for golf carts, fork lifts and such. Trojan T105s are a brand name but there are many alternatives. Rolls I believe also makes one.
You of course have to buy them in pairs and hook in series to supply 12V. Another nice feature, they aren't too much larger than a large auto starting battery so much easier to handle.
KellysEye
Active member
>Leisure batteries are only modified starter batteries..... In some cases I suspect the modification is little more than a different label
I know you put a smiley on that but it is misleading and may persuade somebody to buy the wrong battery. As said Cold Cranking Amp batteries are for starting the engine and golf cart batteries are best for domestic batteries, Trojans seem to be the favourite.
I know you put a smiley on that but it is misleading and may persuade somebody to buy the wrong battery. As said Cold Cranking Amp batteries are for starting the engine and golf cart batteries are best for domestic batteries, Trojans seem to be the favourite.
Whatever type of deep cycle battery you use for your service load, it does not have to have the word "marine" attached to it, that only means that it costs twice the price that it would otherwise.
dylanwinter
Active member
I am of the opinion that in the age of modest power consumers such as led lights and an hour of laptop of an evening, bit of mobile phone charging, it makes buggerall difference. Big batteries are better than small ones. On Katie L I have a big car battery that was rejected from my neighbours merc for the sin of being four years old. I also have a modest leisure battery - about the size of the merc battery - I cannot tell you if one is any better than the other or holds its charge better, or is declining slower. . I do know that the old car battery was free and the leisure battery was £60.
D
D
prv
Well-known member
The point is that "leisure" batteries are neither. They sort of claim to occupy a position in between starting batteries and deep-cycle batteries, but the suspicion is that in at least some cases this is mostly marketing. Certainly even the ones that are specially-made are a lot closer to the "car battery" end of the scale than the "golf-cart battery" end.
Pete
prv
Well-known member
Those sound like our "leisure batteries", yes. Not usually marketed as specifically marine, most of them find their way into caravans etc, but they are what would generally be found in a chandlery and commonly used on boats whose owners aren't picky about their electrical arrangements.
Yep, we can get those here. Also true deep-cycle 12v batteries, and deep-cycle AGMs which is what I have.
Pete
macd
Active member
+1
The only place you're likely to see a marine battery is in old coastal fortifications.
"Leisure" batteries, as Vic wrote, are mostly a con.
Car batteries are designed to start engines. Nowadays you occasionally see batteries advertised as 'smart', but none are smart enough to know whether they're on the M25 or halfway across Biscay. They'll work happily in either place.
So, Erik, if you want a battery to start a boat engine, get a suitably-rated car or van battery. Your engine handbook should tell you what CCA rating it needs. If you want a domestic battery, able to tolerate relatively deep discharges, get something suitable for that.
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prv
Well-known member
My engine battery is marked up as being for a snowmobile
(It's just a 30Ah AGM starting battery, same idea as the better-known Red Flash series.)
Pete
ghostlymoron
Well-known member
I agree that some sailors are quite obsessive about batteries and charging and spend more time checking their BM1 than their wind instruments. Not a problem for me, I've got neither.
SteveSarabande
Active member
I just got two leisure batteries, cheap as chips on some online site. Both add up to 200ah. They start my 10hp vetus just fine and last ok for domestics.
I need to rethink my charging strategy now I am living off grid.
I need to rethink my charging strategy now I am living off grid.
GrahamM376
New member
In some cases I suspect the modification is little more than a different label
I think your suspicions are right. I used to do business with a battery manufacturer many years ago who had a pile of different labels and just stuck on whatever the customer asked for and adjusted the price accordingly. This practice no doubt continues.
Topcat47
Well-known member
I recyled a Motorbike battery for use as a starting battery. All went well until I had a short run of starting problems. Basically it couldn't cope with more than four attempts to start the little SOB before dying. I currently have an old (>10) 80 amp "leisure" battery as a starting battery and an Exide 85ah "caravan" battery as a service battery. Maplin solar panels keep them high when I'm not on board. Bought on price per AH.
wallacebob
Active member
As has been previously stated there is some suspicion of the labelling of "Leisure" batteries, and this http://www.caravanclub.co.uk/media/6552072/technical.pdf?type=archive useful doc from the caravan Club tends to support the theory. From personnel experience (caravan) the Banner brand here seems to be true leisure use type battery.
I use a cheap car battery I got for £5 at scrappy on my lowly boat, but I don't need much juice!
I use a cheap car battery I got for £5 at scrappy on my lowly boat, but I don't need much juice!
Mistroma
Well-known member
I'd agree. I remember meeting to someone socially and he was in the battery business. I think the company was Manbatt and they sold Numax but it was many years ago.
I asked about their range of lorry, caravan and marine batteries as specs. were identical apart from the price. He said that the only difference was the label. I asked if he could be certain and he replied with a laugh "pretty sure as I've often spent time sticking the labels on them".
