AGM OR LEAD BATTERY (1 Viewer)

[Stealaway]

I have no idea how to conduct an accurate capacity test, I assume this is a ‘bench test’ exercise running a known Ah demand on the battery for a defined period or until failure?

All I can say about our batteries is that they didn’t die during 4 days off EHU this weekend.

Obviously it will depend on your demand.
How many hours did you watch the TV of an evenings over those four days.
We expect ours to provide three hours TV every night before we go to bed at midnight - without fail.

 

[Lenny HB]

I have no idea how to conduct an accurate capacity test, I assume this is a ‘bench test’ exercise running a known Ah demand on the battery for a defined period or until failure?

First charge the battery fully and leave it to settle for an hour then:-

For example if it's a 100a/h battery load it with a 5 amp load and run for 5 hours, this will represent a 25% discharge. (adjust load/time to suit the size of the battery)
Disconnect the load and leave to stand for at least 30 min then measure the voltage.
Repeat the test and you will have discharged the battery to 50%.
You can repeat again then it will be 75% discharged.

Always best to test each battery individually if in any doubt.

 

[Lenny HB]

All I can say about our batteries is that they didn’t die during 4 days off EHU this weekend.

With our Gels, last year in a rainy not much sun October we lasted 14 days.

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[RogerIvy]

I have no idea how to conduct an accurate capacity test, I assume this is a ‘bench test’ exercise running a known Ah demand on the battery for a defined period or until failure?

All I can say about our batteries is that they didn’t die during 4 days off EHU this weekend.

There are a few methods to accurately test capacity. This week I’ve been testing some supposedly 420ah LifePO4 cells that actually test out to 240ah. Seller lied. We’ve tested loads of cells and batteries.
I have a spare 50a smart shunt that I can give you if you want to test. You would need to put some sort of load onto it.
Alternately you can buy an inexpensive small tester of the web. They test to a max of 185kw so around 12a before your battery voltage drops. Dead easy to use and very accurate.

 

[Richard n Ann]

Just buy a decent battery monitor and it tells you what should be left by magic

 

[cyberyacht]

I'ver got an 82AH Exide gel collecting cobwebs in my garage if anyone wants to make me an offer I can't refuse. (No horses heads though)

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[Newfie]

Read this

Battery Technology Advances mean big savings and better batteries for Caravans/Motorhomes

The best Leisure Battery is also one of the cheapest - Powerframe Varta LFD90 and Bosch L5. A Deep cycling and Starter battery in one.

www.aandncaravanservices.co.uk

 

[Pusscat]

Have a look at EFB batteries…http://www.aandncaravanservices.co.uk/battery-technology.php, apparently seen as a very effective replacement improvement over AGM For leisure. I’ve had Yuasa L36-EFB 100amp for several years now and no problems, about £120 each.

 

[ChrisL]

For an extra £40 you could get a lead carbon gel battery with a 5 year guarantee and an estimated 1500 cycles at 50% dod rather than the 200 of the Yuasa. I guess it comes down to how long you might be keeping the van and your budget.

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[Newfie]

After a lot of reading I’m replacing my 2 Banner AGM 92AH batteries with 2 of these
12v 90AH Varta LFD 90 Professional Leisure Battery £214 including next day delivery

 

[Carolina]

Sorry for ignorance, but are AGM batteries good for engine battery use? Our battery failed today and RAC recommended AGM.

 

[cmcardle75]

Sorry for ignorance, but are AGM batteries good for engine battery use? Our battery failed today and RAC recommended AGM.

They're generally considered very good to engine battery use. Stop/start systems often specify them as a requirement. It is leisure usage where they are more controversial.

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[Carolina]

They're generally considered very good to engine battery use. Stop/start systems often specify them as a requirement. It is leisure usage where they are more controversial.

Thank you. We'll order one tomorrow.

 

[Drexxer]

You are on borrowed time, got ride of mine when I picked up the van and fitted 3 Gels. Last van AGM's lasted 18 months.

Lenny, which Gels did you go for?

 

[Lenny HB]

Lenny, which Gels did you go for?

I fitted Sonnenschine they make the Exide ones, recently Exide have been cheaper either are good basicly the same battery.

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[Richard n Ann]

Fitted the 80ah Exide ES900 gel 2 years ago, holds charge very well according to the battery monitor

 

[Propshaft]

I had gel batteries when they packed up in Spain bought two AGM batteries that was 6 or 7 years ago they are getting a bit tired now so will probably replace with AGM by the way these batteries have been used quite heavily we always wild camp charge the bike batteries through the inverter and use small electric kettle

 

[Lenny HB]

You have just been lucky AGM are about the worst choice for leisure batteries.

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[Drexxer]

I fitted Sonnenschine they make the Exide ones, recently Exide have been cheaper either are good basicly the same battery.

What amph are they please Lenny?

 

[Lenny HB]

What amph are they please Lenny?

Sonnenschine is78ah Tanya list them as 75 but that is incorrect Exide is 80ah, Exide are cheaper at the moment.

 

[Gerryatric71]

Duplicated information.

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[Northernraider]

Although my agm’s lasted 7yrs I did replace them with gels… only because of the chances that I got lucky with the agm’s….

incidentally, I can’t see all the posts on this thread I think someone has me on ignore…

Mange tout

 

[Clive Mott]

Get your charging systems checked first. If you need to save weight or space or need more energy then go LiFeP04

 

[LostinWales]

Hi All,
We currently have a sail boat with 4 leisure batteries at 110Ah each and 1 start battery of 85Ah higher CCA value (although that also powers the anchor windlass too). We have owned the boat for 16 years, selling to buy an MH .
As we used anchorages a lot, and spend days/nights at sea, we needed to have a better power balance than normal SLI batteries could give, and so eventually have ended up with AGM2 (Euro) batteries.
We changed the charging system to an optimal smart system with the correct profile, which is essential for longevity and delivery. Our setup has a 'normal' 240v charger in the hookup, but feeds into a Sterling Alternator to Battery Charger unit (A2B). The smart charging profile is selected in this unit, and combines Alternator output (and sneakily raises alternator output for battery charging, as these are set by the manufacturer to be optimised for normal vehicle profile use) with the 240v charger. The solar is also input to this unit, although with an MPPT quality unit, that would not be necessary.
I did swap out the original 60A Hitachi alternator for an 80A unit. It will be held to consistently provide 60 to 65A output whule required in stage 1 of the 4 stage charge cycle, also temperature controlled to ensure no overheating. This drops to a float charge when the cycle is done providing a trickle o around 2-3A at 13.9v on absorption charge.
The unit has a splitter to prioritise the start battery to ensure that is ready to start the vehicle.
The battery temperature is monitored, and the charge cycle automatically accounts for this.

Averagely, for the same nominal Ah capacity, we are able to access 80% with the AGM2 batteries, rather than the 50 % for the SLIs. The AGM2 technology is also able to take a faster deep charge cycle, so the batteries can be replenished faster.
I think the comments in this thread about gas discharge are the VRLA variant of AGM (I have these on my motorcycles), but I do not have an issue on the boat with gas detection, it does not happen as described elsewhere in this thread.. As you might imagine, with propane gas equipment in a sealed hull, I am keen not for it all to go off bang or poison us in our sleep, so we have 3 detectors of different sorts.
Our current batteries have been on the boat for 5 seasons, and kept trickle charged over winter on hookup. So far, these have proved to work very well with little performance drop off.

It was an additional cost but so worth it.

Bit of reference:

AGM vs Flooded Batteries: What You Need to Know

Both AGM and Flooded batteries have their own pros and cons. Learn more about the variations that should be considered before purchase or use.

www.crownbattery.com

Alternator to Battery Chargers up to 130A

Instruction Manual PDF Product Information PDF Alternator to battery chargers DC Voltage Max Alt amps Size L x W x D mm Weight Kg Part Number 12 80 250 x 180 x 70 2.5 AB1280 12 130 250 x 180 x 70 2.5 AB12130 24 80 250 x 180 x 70 2.5 AB2480 Remote control ABNRC NOT RECOMMENDED FOR USE WITH...

sterling-power.com

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[Essgeebee]

Yes. It's corrosive and poisonous.

I use one of these which works quite well.

View attachment 530924

I have a Cairn terrier who emits copious amounts of hydrogen sulphide - or some other foul-smelling gas that obviously has sulphur in it. Will your recommended device distinguish between the two? I’d hate to have to chuck my battery outside. Much easier if it’s the dog.

 

[Spriddler]

I have a Cairn terrier who emits copious amounts of hydrogen sulphide - or some other foul-smelling gas that obviously has sulphur in it. Will your recommended device distinguish between the two? I’d hate to have to chuck my battery outside. Much easier if it’s the dog.

It probably would detect both but fortunately it hasn't need to as I always get a visual warning when my Westie has released a whiffy one because he gets up and moves away from that unpleasantly aromatic spot.

 

[PhilandMena]

Your going to get a lot of different advice on here ! A lot of it good, some of it bad and whilst I generally agree with Lenny HB about AGM leisure batteries, there is a new type of AGM leisure battery that IMO is worth considering. Pure Lead Carbon batteries. These are cheaper than Gel batteries. (Gel batteries would last longer though !), They have a much longer life than your standard AGM batterie and can be safety discharged to a much lower lever than a standard AGM battery without any long term damage. There are quite a few manufacturers producing them now and I'll attach a link for one as to give you some idea what there all about.
As Lenny says if your on hook up all the time any old knackered 12 Volt lead Acid battery will do.

Leoch Pure Lead Carbon AGM 12V 100Ah Battery (PLH+C 100)

The Leoch PLH+C 100 AGM Battery. Designed for solar, golf, lighting, industrial, leisure applications and much more. More power than your lead WET acid batteries and has faster charging abilities. 12V 100Ah power output. Dimensions - 341.5L x 175W x 213H

www.tayna.co.uk

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[Spriddler]

.Dup.

 

[PhilandMena]

So all of you with AGM's more than a couple of years old please do a capacity test and post the results here.

An Interesting question and I make just take you up on your suggestion. However, and I'm sure you would agree for this test tom be meaningful, members would have to use the same method to do the test.
IMO (and I would welcome your comment) the test should be done as follows. Assuming the AH rating of the battery is known.
1. Fully charge the battery with a good charger.
2. Disconnect battery and record voltage level each day over the next 2 weeks.
3. After two weeks, attach a drain of a know wattage to the battery, say 2 or 4 amps and record voltage reading each hour until battery is discharged by 50%.
4. Remove drain and calculate capacity (Not 100% certain of how to use the math for this and would welcome advice ???)
5 Check battery voltage each hour to see if battery recovers and if so by how much (Again lost on the math side and would welcome advice ???)

I might do this test with pictures on my Exide ET650 leisure batteries I fitted in 2018. I would not expect them to be at full capacity but uncertain how one determines the % of remaining capacity. Anyone know for certain without guessing ?

 

[ChrisL]

Your going to get a lot of different advice on here ! A lot of it good, some of it bad and whilst I generally agree with Lenny HB about AGM leisure batteries, there is a new type of AGM leisure battery that IMO is worth considering. Pure Lead Carbon batteries. These are cheaper than Gel batteries. (Gel batteries would last longer though !), They have a much longer life than your standard AGM batterie and can be safety discharged to a much lower lever than a standard AGM battery without any long term damage. There are quite a few manufacturers producing them now and I'll attach a link for one as to give you some idea what there all about.
As Lenny says if your on hook up all the time any old knackered 12 Volt lead Acid battery will do.

Leoch Pure Lead Carbon AGM 12V 100Ah Battery (PLH+C 100)

The Leoch PLH+C 100 AGM Battery. Designed for solar, golf, lighting, industrial, leisure applications and much more. More power than your lead WET acid batteries and has faster charging abilities. 12V 100Ah power output. Dimensions - 341.5L x 175W x 213H

www.tayna.co.uk

There are also lead carbon gel batteries available, i have recently installed three 110 ahs, time will tell how well they perform.

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