I’ve often wondered why Lenny hates AGM batteries? (1 Viewer)

[chaser]

AGM batteries were, I am sure, around a lot earlier than stop-start vehicles. They have been used as Leisure Batteries longer than stop-start vehicles as well I have no doubt and are perfectly fine for that purpose.

I bow to all on here who know far more about batteries than I do and you have got all the gizmos that tell you all manner of things about them.
I have none of these things apart from a volt meter on the solar thingy that keeps telling me the batteries are charged up and switches off at least by 11 o clock in any sort of sun .
We have two agms that have been in since I built it over three years ago and nothing has changed in that time ,they just keep working, never seen anything below 12.5 volts with a compressor fridge on all the time , never been on hookup unless it was free.

 

[ChrisL]

AGM batteries were, I am sure, around a lot earlier than stop-start vehicles. They have been used as Leisure Batteries longer than stop-start vehicles as well I have no doubt and are perfectly fine for that purpose.

I did a bit of research after reading your post and you are correct, they were developed in the 80's well before stop start vehicles, they were apparently developed for use in motorcycles and aircraft because of their tolerance for vibration, as for their suitability for leisure use, as some people have had bad results and some good it's probably down to how much lead is in them and having the correct charging profile.

 

[Hoovie]

I did a bit of research after reading your post and you are correct, they were developed in the 80's well before stop start vehicles, they were apparently developed for use in motorcycles and aircraft because of their tolerance for vibration, as for their suitability for leisure use, as some people have had bad results and some good it's probably down to how much lead is in them and having the correct charging profile.

I like AGM over Wet Cell batteries primarily as you won't get leaking acid. You can generally position them on their side as we;; which can be very handy. Just overall a better more flexible battery.
Same as Wet batteries, there are good AGM batteries and not so good AGM batteries. Also different battery technologies are better at certain functions.
A while back the 'talk of the town' for batteries was the Trogan T105 6V Wet Traction Battery and a "proper" installation would have 2 or 4 of these installed . But my understanding is that these are not too good at the higher currents that an Inverter might demand. Really is a case of no one size fits all.

I believe the Gel battery came about due to a German demand for a leisure battery that would not spill in the event of an accident? (I think that is right but it is funny how so many German vans get fitted with Wet batteries ).
I really don't know if Gel is better than AGM (there are massive Gel fanboys who will tell you they are of course) but they seem pretty even to me in terms of specs.
I actually have Gel batteries in my Motorhome without realising it! I thought I got 3 AGM Lead Carbons back in 2020, but when I checked a couple of months ago I found they were Gels and supplied just as that particular model was moving from AGM to Gel.
Doesn't actually bother me either way as I think they perform pretty much the same (my last two installations of AGMS, one 400Ah bank and one 630Ah bank worked perfectly).

 

[ChrisL]

I like AGM over Wet Cell batteries primarily as you won't get leaking acid. You can generally position them on their side as we;; which can be very handy. Just overall a better more flexible battery.
Same as Wet batteries, there are good AGM batteries and not so good AGM batteries. Also different battery technologies are better at certain functions.
A while back the 'talk of the town' for batteries was the Trogan T105 6V Wet Traction Battery and a "proper" installation would have 2 or 4 of these installed . But my understanding is that these are not too good at the higher currents that an Inverter might demand. Really is a case of no one size fits all.

I believe the Gel battery came about due to a German demand for a leisure battery that would not spill in the event of an accident? (I think that is right but it is funny how so many German vans get fitted with Wet batteries ).
I really don't know if Gel is better than AGM (there are massive Gel fanboys who will tell you they are of course) but they seem pretty even to me in terms of specs.
I actually have Gel batteries in my Motorhome without realising it! I thought I got 3 AGM Lead Carbons back in 2020, but when I checked a couple of months ago I found they were Gels and supplied just as that particular model was moving from AGM to Gel.
Doesn't actually bother me either way as I think they perform pretty much the same (my last two installations of AGMS, one 400Ah bank and one 630Ah bank worked perfectly).

I too have three lead carbon gels in my motorhome, before that in my camper I had one Leoch lead carbon agm, it worked well for the short time I had it and charged very quickly using a schaudt B2B it went with the camper when I bought a motorhome and went full time so I don't know if it has lasted well or not.

 

[TheCaller]

I've been watching this AGM vs Gel argument go back & forth over the past 10 years.

My conclusion is that given the correct charging environment is available for the battery type in use, Gels are usually preferred because of their longer life & greater usable capacity - they can be taken to a lower SOC without long term damage.

However - the limitation of Gels is their lower discharge rate. This can become a problem for users wanting to power large inverters - something that appears to be increasingly popular.

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[CazPaul]

I know all about these different figures but if everything keeps working what else can we do?

Bang on, we’re the same as you you, a couple of solar panels, these gel batteries x2 are in their 19th year and still working.

 

[MisterB]

This is taken from the Will Prowse DIY Solar Forum - i dont claim that its accurate - just posting for the grown ups to argue discuss ........


Quote:

"I have been wondering for some time if the "don't discharge your batteries beyond 50%" rule really applies to AGM batteries. AGM batteries claim to be deep discharge, and 50% discharge doesn't seem very deep to me! So I did a little research...

If you look at the data for Odyssey AGM batteries, you find that they are good for 630 discharges to 50% but only 400 discharges to 80%. Seems obvious that the 50% depth of discharge (DoD) is better. But hang on, if you flatten your batteries to 80% DoD, you won't have to do the recharging as often, so fewer cycles. The important parameter is your lifetime capacity in Amp-hours, which you get by multiplying the battery capacity * DoD * number of discharges. For a 225 Ah battery, your lifetime capacity is 71,000 Ah if discharged to 50%, but is 72,000 Ah if discharged to 80%. Indeed, If you look at Odyssey's data for 100% DoD, you still get 72,000Ah of lifetime capacity! For Odyssey batteries, there is absolutely no reason to worry about your DoD, you're not gaining anything by starting up that generator when your battery gets to 50%.

But we don't have Odyssey batteries, we have Harris batteries for which there is a dearth of information about its discharge cycles vs. DoD. So instead I created an "Average" battery from Trojan, Concorde, Odyssey and Rolls AGM products (these were the only ones I could find with detailed DoD data)."



Broken Link Removed

"I've included the 3 data points for the Harris battery, and you can see that its number of discharges under-performs the average, but has much the same overall shape. So now you can see how DoD relates to total capacity for our average AGM battery:"


Broken Link Removed

"So going from 50% DoD to 80% DoD will just lose you 6% of your lifetime output from your battery. Not really worth worrying about.

Take home message: If you're using AGM batteries, don't get too fixated upon getting them recharged once you get to 50% depth of discharge. Any time up to 80% is good. More important is not to leave them discharged any longer than you have to."

 

[ChrisL]

This is taken from the Will Prowse DIY Solar Forum - i dont claim that its accurate - just posting for the grown ups to argue discuss ........


Quote:

"I have been wondering for some time if the "don't discharge your batteries beyond 50%" rule really applies to AGM batteries. AGM batteries claim to be deep discharge, and 50% discharge doesn't seem very deep to me! So I did a little research...

If you look at the data for Odyssey AGM batteries, you find that they are good for 630 discharges to 50% but only 400 discharges to 80%. Seems obvious that the 50% depth of discharge (DoD) is better. But hang on, if you flatten your batteries to 80% DoD, you won't have to do the recharging as often, so fewer cycles. The important parameter is your lifetime capacity in Amp-hours, which you get by multiplying the battery capacity * DoD * number of discharges. For a 225 Ah battery, your lifetime capacity is 71,000 Ah if discharged to 50%, but is 72,000 Ah if discharged to 80%. Indeed, If you look at Odyssey's data for 100% DoD, you still get 72,000Ah of lifetime capacity! For Odyssey batteries, there is absolutely no reason to worry about your DoD, you're not gaining anything by starting up that generator when your battery gets to 50%.

But we don't have Odyssey batteries, we have Harris batteries for which there is a dearth of information about its discharge cycles vs. DoD. So instead I created an "Average" battery from Trojan, Concorde, Odyssey and Rolls AGM products (these were the only ones I could find with detailed DoD data)."



Broken Link Removed

"I've included the 3 data points for the Harris battery, and you can see that its number of discharges under-performs the average, but has much the same overall shape. So now you can see how DoD relates to total capacity for our average AGM battery:"


Broken Link Removed

"So going from 50% DoD to 80% DoD will just lose you 6% of your lifetime output from your battery. Not really worth worrying about.

Take home message: If you're using AGM batteries, don't get too fixated upon getting them recharged once you get to 50% depth of discharge. Any time up to 80% is good. More important is not to leave them discharged any longer than you have to."

There is another factor that you appear not to have included, that is battery voltage at deep depths of discharge, an AGM battery at 80% dod is likely to be putting out around 11.66 volts, how will the 12v devices in the motorhome perform at that voltage?

 

[MisterB]

There is another factor that you appear not to have included, that is battery voltage at deep depths of discharge, an AGM battery at 80% dod is likely to be putting out around 11.66 volts, how will the 12v devices in the motorhome perform at that voltage?

i think you misread my post. i have no opinion on the benefits or otherwise of AGM batteries !!!

my post was for information only from another source, i dont endorse the information or even understand half of it, though i do know what AGM stands for ......

 

[Dorset Diver]

What is the best way to check the capacity of my twin Gels in situ? They have been treated well but have been in the van from new, over seven years now.

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[Lenny HB]

What is the best way to check the capacity of my twin Gels in situ? They have been treated well but have been in the van from new, over seven years now.

Remember that the capacity will reduce by approx 2.5% for each year of the battery's age.

Make sure they are fully charged, preferably test each one separately.

To do a discharge test:-

First charge the battery fully and leave it to settle for an hour then:-
Disconnect all charging methods.

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.

Or you could buy one of these.

150W Intelligent Electronic Load Battery Discharge Tester Meter Detector 150V UK | eBay

Find many great new & used options and get the best deals for 150W Intelligent Electronic Load Battery Discharge Tester Meter Detector 150V UK at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

 

[ChrisL]

i think you misread my post. i have no opinion on the benefits or otherwise of AGM batteries !!!

my post was for information only from another source, i dont endorse the information or even understand half of it, though i do know what AGM stands for ......

Sorry, reading back I realise you were quoting someone else, my apologies.

 

[POH]

You need chargers with a Gel profile.
Gels charge at lower voltage than AGM's and need a long absorbtion charge.

What chargers do you have?

Hi Lenny had a look at

Not sure Lenny I will check in the next few days and get back , m/h is a pilote 740 evidence 21 plate, maybe someone might know sooner than I can check

Hi Lenny I have checked the charger /fuse box I have attached a couple of photos , see what you think maybe looking at lithium instead of gel and a inverter

Got solar panel think it's a 100w / 120w one don't think I have b2b .

 

[Lenny HB]

Hi Lenny had a look at

Hi Lenny I have checked the charger /fuse box I have attached a couple of photos , see what you think maybe looking at lithium instead of gel and a inverter


View attachment 774725 View attachment 774726 View attachment 774727 View attachment 774728

What is the make and model of the chargers?

 

[POH]

What is the make and model of the chargers?

Lenny this is the only charger/fuse box that I can see , the only other things are leisure battery and main circuit breakers .

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[Lenny HB]

Lenny this is the only charger/fuse box that I can see , the only other things are leisure battery and main circuit breakers .

View attachment 774781 View attachment 774782

It is a distribution unit with both a mains charger and a solar controller, the solar can handle 200 watts but it is only a PWM controller.
The unit can be set for standard Lead Acid, AGM, Gel & Lithium batteries.

Here is a link to the instruction manual in another thread.

Pilote 626D EHU not charging the Leisure battery

Hi We cut our trip short this weekend due to the EHU not charging the leisure battery. We usually just park up on site until ready to go home but I wanted to visit a distillery that was not within walking distance. We unplugged and I left my EHU cable on our pitch on return I plugged back in...

www.motorhomefun.co.uk

 

[POH]

It is a distribution unit with both a mains charger and a solar controller, the solar can handle 200 watts but it is only a PWM controller.
The unit can be set for standard Lead Acid, AGM, Gel & Lithium batteries.

Here is a link to the instruction manual in another thread.

Pilote 626D EHU not charging the Leisure battery

Hi We cut our trip short this weekend due to the EHU not charging the leisure battery. We usually just park up on site until ready to go home but I wanted to visit a distillery that was not within walking distance. We unplugged and I left my EHU cable on our pitch on return I plugged back in...

www.motorhomefun.co.uk

Lenny what's a PWM controller , so could I just drop a lithium in if needed providing I throw the switch over and maybe add a inverter.

 

[Lenny HB]

Lenny what's a PWM controller , so could I just drop a lithium in if needed providing I throw the switch over and maybe add a inverter.

Info attached.

 

[POH]

Info attached.

thanks lenny , it is still all gobbledegook to me I like things simple

 

[Lenny HB]

thanks lenny , it is still all gobbledegook to me I like things simple

Looked simple to me.

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[Riverbankannie]

Hi Lenny HB
After 8 years of trouble free life, I think our battery has come to it’s end. The last two nights at Twinwood, the low battery alarm beeped in the early morning about 6am. Set to come on at 11.5v.
You once had a look at it at quackers to help determine what type it was (after your battery talk). I can now confirm it is a 145 ah AGM (eek!)

Having considered all our options, all of which require some sort of help as it weighs 35kg, we have decided simplest option is to replace like for like.
We don’t use an inverter, have a 100w solar and so far in our 8 years of never paying for hook up unless included and long stays off grid at quackers and other rallies, Swaffham for a week for example, we have never run out before now.

I think it would be well over 1k to change to lithium what with purchase price and paying for fitting of new charger etc.
This is our charger which is currently set to Pb but has a gel setting.

Am currently considering these two batteries from Alpha batteries, the cheaper one seems to promise more cycles but the Leoch one currently fitted to new IH.

This is our solar regulator setup and current battery as uncovered so far. If a son were able to help just exchange, what should we do to disconnect ?
Remove solar lead and how? Turn off anything else? Remove negative then positive from existing battery?

And is this the battery master? What to do with that?

I know you are currently fully hands on with Northernraider (very jealous) but your input appreciated even if it is to say don’t get another AGM!

 

[Riverbankannie]

Just to add, we are a bit battery brand skeptic after visiting the premises of Bristol Batteries many years ago for our previous van. An HGV was just in from China delivering new batteries.
When we specified what we wanted, the chap went to the warehouse and got one and then asked what label we wanted on it. All the different brand labels were under the counter.

 

[chaser]

Just what is a cycle and how do you know how many it's done, ? Our batteries are never below 12.5 but the solar puts them back to 14 by dinnertime , is that a cycle? Or does it mean down to 12 and back up again or what?

 

[Pausim]

This is our charger which is currently set to Pb but has a gel setting.

Your CBE charger has Pb and Gel settings but no AGM setting. Why not get a Gel battery instead of AGM. Think how happy you will make Lenny HB .

As you are thinking of buying AGM from Alpha Batteries it might be worth following the advice in their AGM guide.

A Detailed Guide to AGM Batteries - Alpha Batteries

With AGM products becoming more widespread in their use, knowing when you can or should use one and how to look after it properly is all the more important - our guide is here to help.

www.alpha-batteries.co.uk

 

[Riverbankannie]

Your CBE charger has Pb and Gel settings but no AGM setting. Why not get a Gel battery instead of AGM. Think how happy you will make Lenny HB .

As you are thinking of buying AGM from Alpha Batteries it might be worth following the advice in their AGM guide.

A Detailed Guide to AGM Batteries - Alpha Batteries

With AGM products becoming more widespread in their use, knowing when you can or should use one and how to look after it properly is all the more important - our guide is here to help.

www.alpha-batteries.co.uk

I had read that but I can only assume that our normal pattern of use/charging is Ok as has been fine for 8 years.
Not necessarily buying from alpha, depends if can get one locally. I think Bristol Batteries might have one

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[Riverbankannie]

The largest capacity gel that I have found that Will physically fit is 100ah which is quite a step down
Max dimensions available are L350 D 170 H 300

 

[Speve]

The largest capacity gel that I have found that Will physically fit is 100ah which is quite a step down
Max dimensions available are L350 D 170 H 300

heres a couple although not Gel or Agm I think they do have three AGMs biggest 128a

135Ah Leisure Batteries

We sell 135Ah Leisure Batteries at the cheapest prices anywhere. Our 135Ah Leisure battery is an extremely high quality product at a budget price. With a price beat guarantee you can be certain of the best deal in the UK.

www.tayna.co.uk

 

[Speve]

12V 150AH Expedition Plus AGM Deep Cycle Leisure Battery

12V 150Ah fit-and-forget AGM lead-acid battery for leisure, marine & many other deep cycle applications – from Expedition’s exclusive battery range. TECHNICAL INFORMATION Brand - Expedition Voltage - 12V Capacity (Ah) - 150 Construction - AGM Ideal Charge Voltage - 14.6 – 14.8V Top Up Charge...

www.wiredcampers.co.uk

 

[Just smiffy]

The largest capacity gel that I have found that Will physically fit is 100ah which is quite a step down
Max dimensions available are L350 D 170 H 300

Hi Annie, your agm in the last 3yrs has probably been way down on capacity and probably only giving out around 100-110ah or less, with the 100ah gel battery you mentioned you will be able to take it down safely much more then you could with the agm and will be comparable to a new 150ah agm battery…

You will also have the correct charging profile connected too and no need for a vent tube… this is my understanding and I’m sure Lenny HB will be along tonight and shoot me down.. or admit his preaching is getting through to me.

As for changing your battery disconnect the solar + wire where it states PV on the controller, then as you’ve said disconnect battery negative then positive… reconnect new battery in reverse and let the controller see the battery so it can set itself to 12v then reconnect the + wire back into the controller…

Make sure you set your victron controller to GEL in the victron app…

Tayna batteries are recommended but there is another one I can’t think off right now… and don’t attempt to lift them as they are very heavy…

Good luck..

 

[Just smiffy]

Plus I would go for Exide or Varta…

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