How long do leisure batteries hold charge for?

[Capt. Clueless]

The reason I ask is that, Prior to me buying my boat, it had stood in a yard for at least a complete season unused. Only recently, having completed all the exterior works, I moved inside to start a complete rewire. I flicked the switch to on, and everything worked/came on, even the electric bilge pump. (Unwittingly, I soaked my wife in old bilge water as she was unknowingly to me standing by the outlet cleaning the stainless steel, but thats a different story) If that had been a car battery stood for so long, I would be needing to charge it prior to turning the engine over. I was very impressed with the current battery, and my knowledge does not stem into the mechanics of a leisure battery compared to an average car battery. Is it quite usual for leisure batteries to hold charge for long lengths of time if unused please?

 

[reeac]

It's not quite clear to me whether "everything" included starting the engine. If it does then that's very impressive. I reckon that my two Elecsol leisure batteries lose about 3 to5 percent of their charge per month. So I'm sure that they wouldn't start the engine after 12 months. I give them a 24 hour charge in December and another in April. They have just completed 10 seasons of use and one has packed up big time ...probably one cell has failed so I'll be replacing both of them during fitting out next Spring.

 

[Momac]

Good news - sounds like your batteries are in good order.
But do you know with certainty they haven't been charged while the boat was ashore ?
.

 

[vyv_cox]

Two years ago I had to bring my solar panel regulator home from Greece for repair. I disconnected all my batteries (3 x 110 Ah) from each other. Six months later they showed 12.5 volts, worked perfectly including starting the engine.

 

[lw395]

It's completely random IMHO.
I've had motorbike batteries that perform great interms of starting and capacity but self-discharge fairly quickly, like a couple of months, OTOH I looked at a bike the other day that had been untouched for nearly a year, the tiny little battery started the bike no problems, despite needing a bit of cranking. (we span the motor for several bursts with the ignition off to get the oil around the motor, then it took a few goes to start)
It's not even a 'good' make of battery.
I'm not sure leisure batteries will be any different.
Don't rely on it always being as good, try to look after it with a bit of trickle charge now and then?

 

[ghostlymoron]

As luck would have it, I checked the voltage of my spare leisure battery yesterday. I replaced it with a Hankook at least six months ago and not touched it since. The voltage yesterday was 12.5. So it seems that my concerns over it were misplaced.

 

[David2452]

I replaced it with a Hankook at least six months ago and not touched it since. The voltage yesterday was 12.5. So it seems that my concerns over it were misplaced.

I really like the Hankook, I have been fitting them as a first choice for a while and a 190AH sealed leisure battery at around £130 is good value. I often fit quite large banks of four of them.

 

[ghostlymoron]

I think my previous post was unclear. The battery I tested was a numark? which I replaced due to doubts about its capacity. The Hankook seemed the best value replacement and has performed satisfactorily so far.

 

[bignick]

My understanding, limited though it is, is that "leisure batteries" are designed to tolerate a deeper level of discharge than normal "starting" batteries. To do this I believe that they have thicker lead plates than a normal battery, which should make them more tolerant of abuse. It would still be worth topping them up with distilled water and venting them while charging if they have discharged almost completely.

 

[ghostlymoron]

Your understanding is the same as mine. Most leisure batteries including my Hankook is NT top uppable so you have to be careful not to boil them as its not possible to replace the water. I'm lead to believe that there is more acid in them when new to alow for some loss.

My understanding, limited though it is, is that "leisure batteries" are designed to tolerate a deeper level of discharge than normal "starting" batteries. To do this I believe that they have thicker lead plates than a normal battery, which should make them more tolerant of abuse. It would still be worth topping them up with distilled water and venting them while charging if they have discharged almost completely.