The most boring question of 2018 so far?

Homer J

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With any luck the question title may have inspired you to open this thread. Disappointingly it really is a mundane question - nevertheless I would like some advice

My three 85amph batteries have given up the ghost in the cold and I need to replace them so I have some questions

1) What type? Should they be AGM?
2) What make should I buy (obviously I will be restricted to those that fit the space?)
3) Where should I buy them from?

Any advice gratefully received but please make them comprehensible to the hard of thinking, I'm not terribly technical.

PS - could I have killed them by having the battery charger switched on 24/7 when plugged into the mains?
 
Your choice depends on how you use them and the depth of your pockets. The advantage of AGMs is that they tolerate a greater number of charge/discharge cycles, will accept higher charge rates and have a low discharge rate. Therefore popular with liveaboards and those who make high demands regularly on their domestic batteries. deep cycle wet batteries also tolerate more cycles but are slower to recharge. For engine start batteries, if you have an efficient split charging system do not need to be large capacity, but high cranking power (expressed as CCA). Batteries intended for diesel cars are fine, although if you are short of space an AGM such as a Red Flash may be worth considering.

As to makes and suppliers, there are so many and you will find recommendations for a variety depending on who you ask.
 
With any luck the question title may have inspired you to open this thread. Disappointingly it really is a mundane question - nevertheless I would like some advice

My three 85amph batteries have given up the ghost in the cold and I need to replace them so I have some questions

1) What type? Should they be AGM?
2) What make should I buy (obviously I will be restricted to those that fit the space?)
3) Where should I buy them from?

Any advice gratefully received but please make them comprehensible to the hard of thinking, I'm not terribly technical.

PS - could I have killed them by having the battery charger switched on 24/7 when plugged into the mains?

Many times I have answered this type of question. I bought some Numax 120 amp hr leisure from the local farm shop, they are used for electric fences. They lasted 9 years until they failed last year. Cost me about £80 each at the time. I am not a believer in buying Agms after that good experience!
Stu
 
I've used traditional lead acid leisure batteries from https://www.batterymegastore.co.uk/ and my current pair of 110ah batteries have lasted over 9 yrs and still going strong. When laid up ashore I leave a Cetek maintenance charger connected. Good prices and free next day delivery. Make sure you get the correct size and terminal orientation. Used for both engine starting and domestic power.
 
PS - could I have killed them by having the battery charger switched on 24/7 when plugged into the mains?

It all depends upon how clever your battery charger is.

My classic car batteries are on permanent mains charger 24/7 and last for 10 years with a Ctek intelligent charger. The ones on the boat are on permanent charge as well but that's solar rather than mains.

Richard
 
Aren't AGM batteries safer, which less chance of gas leaks etc?

Nothing dangerous about wet batteries if you use them properly.

I am a fan of AGMs. My boat has them, standard equipment (all 5 of them?) and I expect them to outlast my ownership of the boat. The Red Flash in my Morgan is now 14 years old. Just plug in the trickle charger when not in use for any length of time.

You need to take a long term view and be realistic about how you use them as the entry cost is high. The Morgan battery is £140, compared with £60 for a normal car battery.
 
Where are you?

Batteries are expensive to ship and are DAC so have to go overland.

Next question?

What do you expect of them?

As liveaboards, when in Portugal, our requirements are very different to our day sailing and short cruises in the UK.

In the UK we use cheap and cheerful wet leisure batteries (85AH for about £65), sourced from the local caravan shop. They don't last as long but the UK boat has long periods of inactivity sand engine never fails to start off either of these batteries after the winter, even though the batteries have received no charge for up to 8 months!

All about horses for courses.
 
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One reason to keep batteries charged is that they are then virtually immune to freezing. I have kept my very basic batteries fully charged, either with mains or a solar panel. This means that they last some seven years or more. Whether it is worth paying twice as much for twice the life is a complicated question which we will each answer in own way.
 
It's a little surprising that all three of your batteries failed together - does point towards the charger. I make sure my batteries are fully charged at the end of October and then don't charge them again until the Spring. The service battery is called on to run the lights and radio occasionally through the Winter but is still in a good state when the sun comes out again.
 
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