Leisure Battery Capacity. Advice.

oldgit

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Have two 105Ah wet batteries of indeterminate make failing miserbly to provide sufficient power for any length of time due to amount of stuff needing power.
They test as being OK but are 3 years old, had a hard life and suspect too frequently having been run down close to their ruin forever voltage .
Plan to replace both.
Ideally this time want max amp hours batteries but with width and length 345mm x 190 mm the same to fit in existing battery box.
Want to stick with wet due to not being sure that all charging systems (shore /genny/ alternators can cope with any other type plus cost of alternative types of battery.
STD Terminal location at either end of battery please.
Height no problems.
Can I fit a pair of these (or similar) without grief . ?
2 x 150AH LEISURE / SOLAR / OFF GRID / WIND TURBINE BATTERIES 3 Year Waranty | eBay
Yuasa available at similar price.
All comments welcome,
 
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Alex_Blackwood

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Have two 105Ah wet batteries of indeterminate make failing miserbly to provide sufficient power for any length of time due to stuff needing power.
They test as being OK but are 3 years old, had a hard life and suspect too frequently having been run down close to their ruin forever limit.
Plan to replace both.
Ideally this time want max amp hours batteries but with width and length 345mm x 190 mm the same to fit in existing battery box.
Terminal location at either end of battery.
Height no problems.
Can I fit a pair of these (or similar) without grief . ?
2 x 150AH LEISURE / SOLAR / OFF GRID / WIND TURBINE BATTERIES 3 Year Waranty | eBay
All comments welcome,
Ignore the description. A complete load of waffle! They are 150 AH batteries, nothing more and nothing less. 😵‍💫
I won't even start to advise you on what to fit, there are those on this forum who can give far better advise than I. :)
 

Refueler

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First you need to know what load you are putting on the batts .. AMPS .....

Second regardless of what people say - standard cranking battery is good for 40% use of its capacity at low to medium amp draw to give long life. Starting draws high current - but its usually not prolonged - so batterys survive it. They are immediately charged back up again once engine starts. This does not happen on the average boat ... we abuse batterys and expect them to deliver ...
Leisure batterys are more designed to deliver low to medium amp rates and about 50% of capacity ... to ensure long life. Charging back up is best if as soon as needed ...

OP says :

failing miserbly to provide sufficient power for any length of time due to amount of stuff needing power.
They test as being OK but are 3 years old,

That means one of two things :

1. Amp draw is high and capacity cannot provide over time desired....
or
2. Test is telling 'porkies' ..... only a true Load Test can give answer.
 

Supertramp

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Start by understanding what your current demand is and how you use the batteries - are they going flat at anchor overnight (domestic loads) or on passage (autopilot/instruments/fridge). Otherwise you could replace and find the same happens even with larger batteries.

I would also check if the batteries are getting a full charge and holding it - check the resting voltage 12.7-12.8 and the voltage under light load 12.4-12.5 with about 5A. I switched to a smart charger with a proper float cycle and rest when the bank is fully charged. Only the smart charger or a long motor give full charging for me.

I replaced all my lights with LEDs which made a huge difference. I use tablets for routine navigation and leave the plotter off.

I have two 5 year old 180Ah sealed lead acid leisure batteries. At anchor with 12 hours darkness and some diesel heater I use less than 10% overnight. On passage sailing for 12 hours with continuos autopilot, instruments and fridge I use about 10-15% if the solar is off. I have very rarely gone below 80%.

A fitted battery monitor is very useful.
 

PaulRainbow

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I agree with post #2, those Ebay battery descriptions are nonsense, i would avoid like the plague, especially at £180 each !

Lots of good advice in post #5. To give any really meaningful advice we'd need to know what loads you are imposing on the batteries and what charging you have.

210ah isn't a lot of power for your boat.

You also had a lengthy thread on here a short while ago regarding problems charging the batteries, how was that resolved ?

You say the batteries test as OK, how are you testing them ?
 

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Considering the cost of, any, largish battery assembly and the importance of the batteries to meet necessity and pleasure it does seem that restrictions are imposed based on the current battery boxes. I do understand its convenient to remove one set and install a new second set but looking at the location with a bit more enthusiasm might allow you to change the, non negotiable, dimensions you quote.

My understanding is battery sizes are fairly restrictive. A 200 amp LA battery will have roughly the same volume as any other 200 amp battery and based on your dimensions your 'new' battery bank (if you move forward) will have almost exactly the same resource (plus or minus a bit), in terms of amp/hours, as the current house bank. So if you are finding the current resource, in terms of amp/hours, is a bit restrictive - you are not going to change much.

If you want a bigger house bank you need to re-think the replacement, with Lithium (explore what might be possible without dismissing it out of hand - it will cost you nothing to take advice from people who have done what might be needed). And/or look at a battery bank that suits your needs - not the size of a couple of existing boxes.

And a shunt plus meter to define usage costs peanuts, is easy to install, and is almost an essential if you want to maximise battery life. You don't seem to have a monitoring system, or you would not discharge beyond safe limits - you need one what ever you do - invest and instal and you will have more detail of usage your existing bank.

You will have plenty of advice on installation - if you follow the suggestion.

Jonathan
 
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samfieldhouse

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The best thing I have ever done (yacht wise):is to fit a battery monitor. I got a NASA BM1 (around £100) and using it, found my longstanding problems with the batteries going flat was due to the charger not working properly.

Agreed. I live aboard and survive very happily on a single 130Ah AGM battery. Can't recommend an AGM highly enough.
Supported by 2x 100w panels on a Victron MPPT controller. Runs the fridge, laptop and heater.
 

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On a practical note....large lead acid batteries are extremely heavy....and getting things on a boat is often an awkward procedure....as is fitting them because boat builders enjoy putting things in the most inaccessible place they can think of. Also it’s a double job...as the old battery needs to be removed.
Solutions include using smaller batteries in parallel or going down the lithium route (which would give you far more capacity and longevity and they enjoy being run low)
 
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William_H

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I agree with Nigel it is likely the "test" you did on the old batteries was related to short term current supply (cranking amps) capability. The only test for capacity is slow discharge. Which is probably what you are doing in using them. An amp meter checking load current will confirm your current drain is normal and I think confirm batteries have lost capacity. So if they won't do the job you want then replace. As said you want true deep cycle batteries or go lithium. ol'will
 

PaulRainbow

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On a practical note....large lead acid batteries are extremely heavy....and getting things on a boat is often an awkward procedure....as is fitting them because boat builders enjoy putting things in the most inaccessible place they can think of. Also it’s a double job...as the old battery needs to be removed.
Solutions include using smaller batteries in parallel or going down the lithium route (which would give you far more capacity and longevity and they enjoy being run low)
OP has a pair of 105ah batteries, they weigh about 12kg, 22kg not exactly "extremely heavy".
 
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PaulRainbow

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Want to stick with wet due to not being sure that all charging systems (shore /genny/ alternators can cope with any other type plus cost of alternative types of battery.
Would still like further information before making any suggestions, but just wanted to pick up on this point.

Let's say you were considering Lithium.....

First of all, the genny is almost certainly only charging the batteries using the mains charger, but that's by the by. All of the above can charge Lithiums by only directly charging the engine batteries, then using a DC-DC charger to charge the Lithiums, providing the DC-DC charger meets, or exceeds, the maximum loads.

Cost wise, you can install 314ah of Lithium cells for £300. Circa £400 for a BMS, DC-DC charger, fuse etc.
 

Neeves

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OP has a pair of 105ah batteries, they weigh about 12kg, 22kg not exactly "extremely heavy".
Try checking a suitcase onto a plane where the suitcase weighs 36kg - its not extremely heavy but might not be accepted at all, because its just 'heavy'. Many workplaces would not allow a single man to lift 36kg - because it is extremely heavy and a risk to health

Try lifting a 36kg battery from a dinghy - I think I'd describe it as heavy, if not awkward.

Similarly manoeuvring a 36 kg battery into a tight location and the battery soon starts to 'feel' heavy - even off it only weighs 36kg.

Obviously none of this matters, so much, if Old Git is actually 30 years old (which is old to a 15 year old) and he keeps his yacht with access to shore not necessitating a dinghy - but we don't know. He might actually be 75 and I would recommend against him try to lift a 36kg battery to fit in a tight space on a yacht. An LA battery times 2 off seems a really good reason to look at Lithium.

Jonathan
 

Neeves

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Your batteries may turn out to be serviceable.... we don't know. I believe the recommendation is to not mix batteries, of different age and different capacities (which means even if one battery has some life it might need to be retired (or treated differently).

My knowledge may be wrong - and I am sure I will be corrected (some will even sneer at my ignorance) - I'm kite flying.

Jonathan
 

Sandy

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What power monitoring system do you have?
Have two 105Ah wet batteries of indeterminate make failing miserbly to provide sufficient power for any length of time due to amount of stuff needing power.
They test as being OK but are 3 years old, had a hard life and suspect too frequently having been run down close to their ruin forever voltage .
Plan to replace both.
Ideally this time want max amp hours batteries but with width and length 345mm x 190 mm the same to fit in existing battery box.
As ever a few questions:
  • Are they both house, do you use one ore either of them as an engine starter battery?
  • How do you know they are failing miserably to provide sufficient power?
  • What sort of power management/monitoring system do you have?
  • How are you charging them?
  • Why do you think that 3 years is an acceptable lifespan for them?
  • Do you have a back of fag packet or spreadsheet note of your power consumption?
Only once you understand those questions can you really decide to recycle them. Some places will pay $£€ for old batteries. If you have a friendly local garage, an independent not a main distributor, you might be able to get them to desulfate them.

Lets assume they are bog standard Lead Acid, whatever that means these days, have you looked replacing them with AGMs?

A few advantages of having AGMs:
  • They can be discharged to a deeper level, but ideally don't;
  • They accept a charge faster; and
  • If they get cracked you don't have battery acid sloshing about.
 

Refueler

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I agree with Nigel it is likely the "test" you did on the old batteries was related to short term current supply (cranking amps) capability. The only test for capacity is slow discharge. Which is probably what you are doing in using them. An amp meter checking load current will confirm your current drain is normal and I think confirm batteries have lost capacity. So if they won't do the job you want then replace. As said you want true deep cycle batteries or go lithium. ol'will

Tks Will ....

thought for a mo - I was being ignored ... :eek:

Lets be honest -- I reckon that 90% of onboard capacity problems are user related ... we add gear to our boats and quite often do not consider the impact on battery drain. We think - arrr its only a few hundred mA ... but as we add gear - they add up to A's .... and soon we end up as OP ....

I have a similar situation of 2x 80A/hr domestics LA .... battery boxes designed into the boat cannot take more than 90 A/hr size ... Boat has fridge .. and all the other stuff common on coastal cruisers .... such that my 2 domestics have been killed ...
Its not stuff I added - but by previous owners and original boat design. The Solar on the cabin top just doesn't keep up ... estimated at a 50- 60W panel ..
By my reckoning - I really need not 2x 80 (160 with actual use 80 A/hrs) - but over 300 A/hrs to give me at least 150 usuable ... with solar of at least 150W or more ..
 
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