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Mobility scooter batteries as marine batteries?

slawosz

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As my main battery might be dying, instead of getting huge new one, I am thinking about building a bank based of those ones: 2 x 12v 17AH MOBILITY SCOOTER BATTERIES - SAME SIZE AS 18AH 20AH 21AH 22AH | eBay
Are they suitable for boat? Reason is that my main battery is cockpit locker, quite high as boat is very narrow and there is no better place. And I could place smaller batteries in more suitable places, under the bunks.
 

LittleSister

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I suspect those batteries may neither put out enough amps for engine cranking, nor have enough amp hours capacity to be useful as domestic batteries.

For battery cranking, consider AGM batteries such as Red Flash These are tiny, and can also be used stood on their sides or ends, but they are pricey. They have relatively low amp-hours capacity, but high CCA (cold cranking amps) and are easily capable of putting out very high amps for the short period required for engine starting. I've had Red Flash ones on previous boats and found them very satisfactory and long-lasting for this purpose.

I suspect that for domestic high-capacity batteries 'there's no substitute for cubes' (and weight!).
 

slawosz

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Just to specify - I have low energy needs - sounder + log, lights if sailing during nights (never happened yet) and VHF. Outboard engine only. 3.3 HP outboard pushes my boat quite well. Oh, and I have 20 W solar pannel with controller.
 

Refueler

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The Scooter battery's will be powering brushless motors at a moderately low ampage.
The point is that such batterys can supply reasonable loads - BUT there is a matter you should build into the system - charge level protection.
You need to find out exactly what composition they are and what is acceptable lowest voltage level they can safely be discharged to. If you can sort the charger that the Scooter uses then solved.

Dropping batterys in when changing formats is not just a matter of change ... you have to make sure you can maintain them and charge to gain the benefit.

The statement "2 x12 Volt 17Ah Deep Cycle Cyclic batteries " is a misleading one ... and does not mean you can discharge these to low level and just charge up again without possible consequences. Deep Cycle is only in reality another 15 - 20% discharge potential more than a conventional cranking battery. Cranking battery of 17A/hr would be ok with supplying about 40 - 50% of its capacity ... ~ 7 - 8A/hr. So your 17A/hr Deep cycle is good for about 10 A/hr .... but get it charged up asap.

Your Solar panel will be good for this but slow .... 20W rated but actual ? probably lucky if 10 - 15W out ... that's ~ 1A charge rate ...

I think you were also looking in another thread to use a small SLA battery ?? What happened to that idea ?
 

Poey50

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As my main battery might be dying, instead of getting huge new one, I am thinking about building a bank based of those ones: 2 x 12v 17AH MOBILITY SCOOTER BATTERIES - SAME SIZE AS 18AH 20AH 21AH 22AH | eBay
Are they suitable for boat? Reason is that my main battery is cockpit locker, quite high as boat is very narrow and there is no better place. And I could place smaller batteries in more suitable places, under the bunks.
I'd be concerned by the word "reconditioned" and what that might mean. (Swapped out old batteries from mobility scooters and wiped down with a damp cloth?) Elsewhere they are described as "new". They are also said to be the result of a cancelled order. Needs a large pinch of caveat emptor, IMHO.
 
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TernVI

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Personally I would prefer not to buy batteries of a brand I'd never heard of.
I would be put off by any hint of 'not brand new'.
Ideally, freshly filled with acid while I watch.
For an extra £20 you can get Lucas or Yuasa.
For a 12V system, a single bigger battery might be better? Or do you intend to alternately take them home to charge?
 

Refueler

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OP's wish to split the battery system into smaller units and then be able to place in other areas - is something that I have contemplated on previous boats of mine.
The question is whether the batterys he linked to are worth it. Maybe the specific ones he linked to are not - I don't like reconditioned either - but the concept he's considering is fine.
In reality its not really that much different to most of us with two or more large batterys .... he just doesn't need large batterys.

I hope OP has not been frightened off ....
 

pvb

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As my main battery might be dying, instead of getting huge new one, I am thinking about building a bank based of those ones: 2 x 12v 17AH MOBILITY SCOOTER BATTERIES - SAME SIZE AS 18AH 20AH 21AH 22AH | eBay
Are they suitable for boat? Reason is that my main battery is cockpit locker, quite high as boat is very narrow and there is no better place. And I could place smaller batteries in more suitable places, under the bunks.
The batteries you linked to are used, and are silly money. For the size of battery I guess you have, weight isn't a big issue. Just get a replacement - but buy new!
 

slawosz

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Hi everyone,
@Refueler is right.
I want to get rid of one heavy battery with awkward access and use few smaller ones - say 4x20Ah in a reasonable price. I want max 80 AH. The link is maybe unfortunate, I can go for something like this: Yuasa REC22-12 Cyclic/Golf Battery 12V 22Ah
I own Achilles 24, and it's really teeny tiny boat. I don't need starting battery, just basic electric - lights sounder log, VHF now and maybe Autopilot in the future.
I am looking for a recommendation as well.
 

pvb

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Hi everyone,
@Refueler is right.
I want to get rid of one heavy battery with awkward access and use few smaller ones - say 4x20Ah in a reasonable price. I want max 80 AH. The link is maybe unfortunate, I can go for something like this: Yuasa REC22-12 Cyclic/Golf Battery 12V 22Ah
I own Achilles 24, and it's really teeny tiny boat. I don't need starting battery, just basic electric - lights sounder log, VHF now and maybe Autopilot in the future.
I am looking for a recommendation as well.
How often might you need to replace the one battery? Weight isn't a real issue. Just get a decent battery to replace your existing battery. Maybe something like this - Exide 110 AGM Car Battery 80Ah AGM800 EK800
 

Refueler

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How often might you need to replace the one battery? Weight isn't a real issue. Just get a decent battery to replace your existing battery. Maybe something like this - Exide 110 AGM Car Battery 80Ah AGM800 EK800
I have to agree though with such .. if you can accommodate the larger single battery - then why not stick with it. Another factor is that you already have started to add to your list by saying later an Autopilot ... as you add things - your power demand increases. One of the problems with using banks of smaller batterys is if one or more deteriorate faster than the others .... they then drag the others down and you end up with a poor system. Especially if you start adding demands.
I'm not a supporter of particular brands of batterys - I'm a cheapskate and buy good second hand ones from breakers yards. They usually have a load tester to check it before you part with hard earned. They usually last me many years and they start my 43hp Perkins ... not suggesting you do same - but just commenting.
 

William_H

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West Australia
I would think scooter batteries would be ideal for OP requirements. I seem to have 2 "shop rider" scooters at home. These are at the heavy end of the range available. They have 2x40AH deep cycle batteries. Last pair I bought were around 110 squid each. from Jaycar. (Oz) A new set of batteries cost more than the purchase price. The first gopher as we call it was bought cheap for towing the ali dinghy down to the boat. Works out really well even on the steep hill back home. I found I use it for all sorts of trips where I should walk for exercise but you can carry all sorts of things on it. The second became available cheap and I could not, not buy it. Feel a bit like a handicapped person but just shrug that off and enjoy the ride.
Batteries are in series with a charger for 24v from mains. However I have a pair of 10w solar panels in series that charge 2 scooters in parallel that mostly keep them charged. I imagine under some circumstances the current drain is quite high like 12 amps or so. ol'will
 

shaunksb

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OP, I did just that in my previous 24’ Jaguar. I can’t remember the make but they were a pair of American golf cart 45ah AGM/Gel ones.

They were brilliant.

They fitted into one standard battery box. Took plenty of abuse, ran everything including tillerpilot and even my eberspacher no problem and charged up from a 20 Watt solar panel.

Edit - Ritar was the brand.
__________________________
 
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Refueler

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Golf Cart batterys are hard working items .... many are 6v and then ganged to provide the required voltage.

A larger battery that is excellent for our use - IF you can accommodate the size : Truck Batterys designed not only to start the diesel engine - but also to power the tail-lift. Truck dealers usually sell them priced on capacity ... and often a lot cheaper per A/hr than other sellers. You literally cannot get a harder working battery ...
 

slawosz

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Standard battery box is too small for my tiny yacht, picture below, hence the idea for 4x20 Ah. But I won't do it until next year. @Refueler what kind of device are breakers using to asses battery condition? Do you think normal garage could help me with mine (its lesuire battery).
Here is (old) photo of my yacht with battery in box - you can see its hard to fit anywhere....
 

slawosz

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Oh, and autopilot will be rather last 'thirsty' device. If I will have need for more power, it would mean I will have more time to sail which will mean bigger yacht :) But I don't see its going to happen (or maybe I should start playing Euromillions?).
 

Refueler

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Breakers yards usually have the large two handled load tester they press onto the battery terminals ... it basically puts a large load on the battery and you read of the load voltage. Keep it on for a short period to see if it changes. Most garages have similar ...

I have had very good life out of Breakers yard batterys ... but no g'tee others will. My reason apart from saving a cart load of money ! is that often the battery is good from a crashed / wrecked car. Very few people remove that good battery from the car they scrap - in fact many yards will be upset if you try .. they want the battery as part of the bits they can sell.

As regards your battery box ... my 2 batterys sit under the rear divan in main cabin. The box is plywood with a GRP lining to sides and bottom - sealing the ply in case of spillage. I know that in modern terms - some say this is undesirable location .. fair enough. But to change would mean serious rewiring etc.
Can you not find a space under an aft bunk close to companionway ? You post that your battery needs are minimal - so locating away under a bunk - is that not an option ?
 
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