Leisure Batteries ...a sorry tale

[Johnw123]

Hi All

By trade I am an electronic engineer with many years experience but this is a story about being lazy and a bit thick It does have a happy ending and is probably a replay of many of the posts here but I hope the information will be of use

When we purchased our California (3 years ago) it remained in storage at the dealers from September thru to January. Its a long story as to why that happened so I wont bore you. Suffice to say that the leisure batteries were completely flat on receipt of the van. The one thing to never do with a lead acid battery is to allow it to go completely flat and remain there for some time. So knowing that they were flat and may have been damaged I asked the dealer to check them at the first service. The answer was that the batteries were fine !

So we used the van for lots of trips in the UK and abroad and are extremely happy with it. But....the batteries dropped quite quickly from fully charged over a few days and had to be charged up again ...not a big deal and I thought there must be a small permanent load and thats what draining them. I even (non scientifically ) ran the fridge etc over a few days just to see how long the batteries would hold up.... around 3 days so not too bad?...thats the lazy bit. So we kept using the van as as we are normally plugged in on site it was never an issue.

Then along comes covid and the van just sits there. Then I got scientific about my electricity bill and usage at home and one thing came up consistently in that the van pulled reasonable amount of power on charge and it didnt go down.... As lead acid batteries charge the rate should drop off to just a small "top up" current once they are up to full charge.

With lock down easing and the van going to be used again I took a punt (an expensive one) and purchased two new batteries. You will ask ..why not go back to the dealer? good question and mainly down to the fact that I think they are useless and life is too short to argue with them.

So two new batteries later and I will share the results of how the batteries should hold up (and should have done from day one !)

Batteries were almost fully charged when fitted and display on van showed 14.4 volts + 4 amps at 1630 dropping to zero at 1725. I then unplugged the van and noted no background current flow on van display.

5 days later 12.5 volts and 90%

4 days later at 1130 and display showed 12.4 volts 100% so I switched on the fridge which showed an initial 4 amps. one day later at the same time the van indicated 12.4 volts and 90%

5 days later the van indicated 12.3 volts and 80 % (fridge set on level 4 throughout test)

This was much better than I had seen before!

I then charged the batteries again

1146 14.4 + 6.4 amps
1350 14.3 + 3.4 amps
1500 14.3 + 2.8 amps
2015 13.2 + 1 amp

Then unplugged van

Then left van with fridge switched off until yesterday (14 days) and batteries still at 100% and 12.3 volts. You will probably note that the percentage seems to move around a bit but it is only an indicator. The voltage at any given time is probably the better indicator... if the voltage drops below 12 volts it will require a charge.

Both the old batteries would not hold a charge when left with nothing connected and one wanted a permanent charge. So in lots of ways I am kicking myself as I should have gone back to the dealer. What my tests here show is that the drain on the batteries is very small when the van is just left. The advice in winter to charge it once a month for a full day given in many posts is probably sound and should be more than OK with good batteries.

So I only have myself to blame when I should have (and do) known better . Do not let your batteries go completely flat and if they are when you collect your van be very suspicious and have it noted (or checked by a dealer that actually know what they are doing ). If they have been flat for some time demand a replacement as there is a very good chance they are damaged.

And the other thick bit? There are two batteries at 80 ampere hours ...that is a significant amount of power and should sustain the fridge for at least 4 to 5 days!

 

[Ozzy Pete]

We had our batteries replaced under warranty when I noticed a 10% drop per day. Took it in on the very last day of the 3 year warranty period and they tested them both and they agreed they were bad. We now make sure that EVERYTHING is switched off. Main console especially and our 2 cameras unplugged. Although these things are only a small drain over a long period of time they flatten the batteries.

 

[Vagophile]

Although these things are only a small drain over a long period of time they flatten the batteries.

Unless you fit solar...

 

[Eber123]

The 2x AGM batteries with 80 Ah each, shouldn't they only be used down to 50%? Meaning that at the end there are only 40 Ah per leisure battery available? I am not so good with this?

JohnW123 did you change the batteries yourself? Did you replace them with the original VW batteries or with third party batteries? May I ask how much they cost?

The reason for this is, that my camper will be 4x years at the end of July. I think the batteries are ok because I ensured that they are charged every month and the van is my daily drive. But with the Pandemic we have not used the van in camping mode for many month. Because of this I don't know how long the batteries last if they are under pressure. It might be they need to be replaced maybe sooner than later.

If I need to change the leisure batteries I was wondering if I can get better batteries. I don't want to even ask for Lithium batteries, because I can't afford them. But I was wondering if the VW original leisure batteries with 80 Ah each can be replaced with 100 Ah or even 110 Ah. For a bit more investment the electric power could be improved a bit. But as I said, I am not good with all these battery issues.

Happy charged California,
Eberhard

 

[Ozzy Pete]

Unless you fit solar...

That’s true but to plug into the mains once a month shouldn’t be a problem for most unless you live in a flat and can’t get to a power point.

 

[WelshGas]

The 2x AGM batteries with 80 Ah each, shouldn't they only be used down to 50%? Meaning that at the end there are only 40 Ah per leisure battery available? I am not so good with this?

JohnW123 did you change the batteries yourself? Did you replace them with the original VW batteries or with third party batteries? May I ask how much they cost?

The reason for this is, that my camper will be 4x years at the end of July. I think the batteries are ok because I ensured that they are charged every month and the van is my daily drive. But with the Pandemic we have not used the van in camping mode for many month. Because of this I don't know how long the batteries last if they are under pressure. It might be they need to be replaced maybe sooner than later.

If I need to change the leisure batteries I was wondering if I can get better batteries. I don't want to even ask for Lithium batteries, because I can't afford them. But I was wondering if the VW original leisure batteries with 80 Ah each can be replaced with 100 Ah or even 110 Ah. For a bit more investment the electric power could be improved a bit. But as I said, I am not good with all these battery issues.

Happy charged California,
Eberhard

You can fit larger capacity batteries. The problem is that the physical size of the batteries is critical because of where they are fitted.
I wasn’t able to find any larger capacity, quality batteries.