Wrong batteries??

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Hi all,
after nearly a year if owning my 'new to me' Motorhome I find I have the wrong leisure batteries fitted!
We are away in it at the moment and a couple of nights after being 'off grid' I've found the control panel flashing red & had to turn everything off. That included using TV for an hour, lights & leaving heating (gas) running all night. They recovered after 30 mins or so (12 volts) & after the solar panel kicked in when the sun came up they were soon back up to 14 volts.??
After asking an expert (and realising the obvious!) It turns out that if your batteries say 'stop/start' on them they aren't really leisure batteries but normal car batteries 🤬 this is quite annoying after buying the Moho from a dealer!
Can anyone recommend somewhere to get a proper pair from? AGM preferably - and does anyone want to buy a car battery or 2 😬

Cheers Chris

20220514_121410.jpg
 
Your biggest problem might be that you think the batteries are charged after a bit of sun on the solar panels, (unless you have a massive solar array) all you are seeing at 14v is the solar charge volts not the actual state of charge of the battery.
 
Why do people know all about AGM batteries as the Hab battery to get when you almost could not buy a worse battery!

A standard sealed lead acid hab battery is better than AGM unless you can afford Gel which are better or Lithium which are now the best but most expensive choice.

Please don’t buy AGM - very overrated - loads of tales of woe about them on here!
 
You need a proper multimeter, not some sales gimmick display the converter fitted.
You have 92 usable amps and that shouldn't be that discharged overnight.
14v isn't the battery voltage, it's the charge voltage and will take quite a few hours to bring the batteries up to full charge.
After an hour with no charge and no load a full battery will show around 12.7v.
I would check the volts out with a multimeter directly onto the battery terminals.
 
Hi all,
after nearly a year if owning my 'new to me' Motorhome I find I have the wrong leisure batteries fitted!
We are away in it at the moment and a couple of nights after being 'off grid' I've found the control panel flashing red & had to turn everything off. That included using TV for an hour, lights & leaving heating (gas) running all night. They recovered after 30 mins or so (12 volts) & after the solar panel kicked in when the sun came up they were soon back up to 14 volts.??
After asking an expert (and realising the obvious!) It turns out that if your batteries say 'stop/start' on them they aren't really leisure batteries but normal car batteries 🤬 this is quite annoying after buying the Moho from a dealer!
Can anyone recommend somewhere to get a proper pair from? AGM preferably - and does anyone want to buy a car battery or 2 😬

Cheers Chris

View attachment 731034


That battery is suitable as a leisure battery and is AGM. I think you'll be trying to find room for more solar soon ,😀

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You need a proper multimeter, not some sales gimmick display the converter fitted.
You have 92 usable amps and that shouldn't be that discharged overnight.
14v isn't the battery voltage, it's the charge voltage and will take quite a few hours to bring the batteries up to full charge.
After an hour with no charge and no load a full battery will show around 12.7v.
I would check the volts out with a multimeter directly onto the battery terminals.
I have tested both current ( no pun intended!) Batteries and after a full charge & being left for 6 hours disconnected both read over 13 volts - so they are obviously ok.
 
Your biggest problem might be that you think the batteries are charged after a bit of sun on the solar panels, (unless you have a massive solar array) all you are seeing at 14v is the solar charge volts not the actual state of charge of the battery.
I have tested both current ( no pun intended!) Batteries and after a full charge & being left for 6 hours disconnected both read over 13 volts - so they are obviously ok..
 
That battery is suitable as a leisure battery and is AGM. I think you'll be trying to find room for more solar soon ,😀
Apparently not as according to the 'expert' leisure batteries are meant to be deep cycle and 'stop/start' ones are for heavy load over short periods??
 
Why do people know all about AGM batteries as the Hab battery to get when you almost could not buy a worse battery!

A standard sealed lead acid hab battery is better than AGM unless you can afford Gel which are better or Lithium which are now the best but most expensive choice.

Please don’t buy AGM - very overrated - loads of tales of woe about them on here!
Have you had any personal experience of them?
 
There are now a few new AGM leisure batteries available to Motorhomer's and you might like to consider the Leoch Pure Lead Carbon series of leisure batteries that can be charged with a standard Lead Acid battery charging profile. Will allow the battery to safely be discharged below 50% SOC and can be quickly charged from a low SOC and most importantly provide 0000's of cycles. Do not be put off by members who state all AGM leisure batteries are useless. This is simply not the case.

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That battery is suitable as a leisure battery and is AGM. I think you'll be trying to find room for more solar soon ,😀
I have to say we only have one solar panel & I don't know what rating it is but it's performing really well - looking at the controller it was putting power out even in the rain/clouds!

20230317_104357.jpg
 
By the way I would like to give a huge thank you to everyone for their comments - that is exactly what I was after and as usual you have not disappointed 😁
 
AGM are not a good choice for leisure batteries and don't get worse ones than Banner I know from personal experience of them.

If your batteries were flat in the morning on good sunny days in June with a single solar panel it will take 4 to 5 days to fully recharge your batteries at this time of year two to three times that & that assumes you are not using them.
The battery should charge up to 14.4v or 14.7v depending of the type of AGM and won't be charged until the voltage drops to 13.8v.for an AG

I have tested both current ( no pun intended!) Batteries and after a full charge & being left for 6 hours disconnected both read over 13 volts - so they are obviously ok..
Voltage is only an approximate guide I expect if you do a slow discharge test they won't have much capacity, when my Banner AGM's failed at 18 months old one had 10 ah the other 11 ah.
 
You need a proper multimeter, not some sales gimmick display the converter fitted.
You have 92 usable amps and that shouldn't be that discharged overnight.
14v isn't the battery voltage, it's the charge voltage and will take quite a few hours to bring the batteries up to full charge.
After an hour with no charge and no load a full battery will show around 12.7v.
I would check the volts out with a multimeter directly onto the battery terminals.
Sorry to hijack the post … so if I have a 110amh battery that after two hours off charge shows a steady voltage of over 12.8 v but only last a couple of hours when used in the van ( TV and some lights) what technically could cause that ?
 
Sorry to hijack the post … so if I have a 110amh battery that after two hours off charge shows a steady voltage of over 12.8 v but only last a couple of hours when used in the van ( TV and some lights) what technically could cause that ?
A :swear2: battery, see my post #13

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AGM are not a good choice for leisure batteries and don't get worse ones than Banner I know from personal experience of them.

If your batteries were flat in the morning on good sunny days in June with a single solar panel it will take 4 to 5 days to fully recharge your batteries at this time of year two to three times that & that assumes you are not using them.
The battery should charge up to 14.4v or 14.7v depending of the type of AGM and won't be charged until the voltage drops to 13.8v.for an AG
They went down to 11 volts during the night but recovered to over 12 after 30 minutes or so - without being plugged in or any type of charging. In the morning after the sun came up the solar had charged them back up to over 14volts & everything was working ok. It really points to the fact that they aren't deep cycle batteries I think??
 
They went down to 11 volts during the night but recovered to over 12 after 30 minutes or so - without being plugged in or any type of charging. In the morning after the sun came up the solar had charged them back up to over 14volts & everything was working ok. It really points to the fact that they aren't deep cycle batteries I think??
Just crap AGM batteries.
 
Voltage is only an approximate guide I expect if you do a slow discharge test they won't have much capacity, when my Banner AGM's failed at 18 months old one had 10 ah the other 11 ah.
I agree completely Lenny HB but can't really test them till we get home in a week or so 👍
 
I had Banner AGM in the first Autotrail I had but they did not last long. Techno used to like Hankook sealed lead acid and I had a pair of those which lasted 5 years then I had a pair of Varta sealed lead acid which are still going strong but I have not long changed to Lithium.

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They went down to 11 volts during the night but recovered to over 12 after 30 minutes or so - without being plugged in or any type of charging. In the morning after the sun came up the solar had charged them back up to over 14volts & everything was working ok. It really points to the fact that they aren't deep cycle batteries I think??
But you had your gas heating on al night which probably has a 12v fan as well to circulate the hot air. That can use a fair few amps.
 
Sorry to hijack the post … so if I have a 110amh battery that after two hours off charge shows a steady voltage of over 12.8 v but only last a couple of hours when used in the van ( TV and some lights) what technically could cause that
Storage capacity is down....batteries failing.

Just yesterday I charged an old 100ah battery showing 3v.
Once fully charged (13.6v) and rested for a couple of hours (12.6v) the voltage was good but storage capacity was down to 45%.....that's a capacity of just 45amps instead of 100amps for a healthy battery.
 
But you had your gas heating on al night which probably has a 12v fan as well to circulate the hot air. That can use a fair few amps.
Yes but we have 2 leisure batteries - I would hope they would last longer than that?

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They went down to 11 volts during the night but recovered to over 12 after 30 minutes or so - without being plugged in or any type of charging. In the morning after the sun came up the solar had charged them back up to over 14volts & everything was working ok. It really points to the fact that they aren't deep cycle batteries I think??


Sorry to hijack the post … so if I have a 110amh battery that after two hours off charge shows a steady voltage of over 12.8 v but only last a couple of hours when used in the van ( TV and some lights) what technically could cause that ?
The liklyhood is the voltage reading you are getting after 2 hours on the charger is the voltage coming from the charger into the battery. If you were to didconnect the charger and give the battery a couple of hours rest you would get a better indication of the true state of the battery. There is anouther condition that would be possible with the batteties indicating they are fully charged and going flat very, very quickly and that woild be when the battery capacity has more or less had its day.
 
They went down to 11 volts during the night but recovered to over 12 after 30 minutes or so - without being plugged in or any type of charging. In the morning after the sun came up the solar had charged them back up to over 14volts & everything was working ok. It really points to the fact that they aren't deep cycle batteries I think??
Not really, I think your being fooled by the voltage coming from the charger and/ or the solar panel. This is what your seeing rather than the true state of the batteries. It will take many hours to fully charge a depleted battery and its very difficult to measure a battery state when thete is a load on it.
 
What are you using now? We are off abroad for 3 months in afew weeks & I would like to get it sorted.
It was in my last van fitted a couple of of Schonennschine 78ah Gels, transferred them, to my current van and fitted a third now over 7 years old and performing like new.
Schonennschine 78ah and Exide 80 ah Gels are similar both made in the same factory buy whichever is cheaper.
 
The storage capacity of batteries deteriorates as they are cycled (charged / discharged). Heavier the use of the battery the faster the deterioration. Lead-acid batteries (and AGM is a derivative of these) don't like being discharged more than about 50% of their total. Go beyond that a few times and their ability to accept and hold a charge is compromised. It's down to the chemistry and that to take a charge there are chemical reactions between the lead and solution, and over time the materials have deteriorated as the reactions take place.

Most batteries also have a rate at which they can provide current, or accept charge. In theory batteries classed as leisure should be better able to offer a lengthy gradual discharge, and charge whereas the stop start engine battery is better at a high load for short period. Realistically, I doubt most lead-acid and AGM is really that different.

Lead-Acid voltages can be deceptive as to the state of charge. You need to let a battery settle, an hour or so, after a charge / discharge for the voltage to stabilise. 12.7V would indicate a full charge, subject to the capacity the battery can at that time hold. 12.0V is just under 50%. To charge a battery, you are putting in a bit more voltage, and of course current, than the battery would operate at. Hence your solar and even mains charger creating apparent voltages of 14V or more. Decent charging systems will also have a bulk (battery is being charged), absorption (almost full) and Float (maintaining full charge) phase, where the input voltages and currents change, float, being a lot less voltage than bulk. There may also be an equalisation option, to try and correct batteries that are perhaps struggling.

In a similar vein, as the batteries work to give out a current, a chemical reaction is taking place. Too heavy a discharge the lead plates in the battery can actually twist and buckle, and the acid can start to boil (hence the need in non sealed batteries for these to have ventilation). The battery voltage appears to drop, and later may recover a bit as the reactions stop.

It can take some time to recharge batteries. If say you have 100Ah capacity (for your good condition battery), and you have used 50%, so need 50AH, but can only charge at 20A off your charging system you will need 2.5hours. If you have solar, say a 100W panel, then it's maximum output would be around 8A, so you'd need over 6 hours to recharge, but at this time of year you may be lucky to get 75% of that panel for an hour, and then a lot less during the earlier and later daylight hours dwindling to nowt.

Some charging systems can be monitored so you can see the amount of wattage that has been put in, and used. This can help you understand the state of your batteries, what you have available to use.

This all suggest the batteries have had it. They are now well down on their capacity from original manufacturer charge rating. The significant drop in voltage during discharge shows they are working too hard to provide the electricity. The voltage during charging is the product of the charger, not battery. If having apparently had discharge to a too low voltage, and yet they seem to stabilise to a correct voltage after charging for a short time you know something is wrong.

Note that the charging voltages of lead-acid, differ from desired charging profiles of AGM, GEL, Lithium. If changing battery chemistry check your charging systems are compatible.

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