Leisure battery failure ?

[RichardHelen262]

We have just spent 2 weeks on emu on a campsite in Spain we left yesterday drove fo about an hour when we stopped
The Sargent control panel showed that the leisure battery was at 10.5 volts.
But we had good sunlight and when we returned to the van 3 hours later it was at almost 12 volts,we then drove for another 3 hours and the battery was still just about 12v but whilst the engine was running it was well above 13v.
Once the sun went down it quickly went back down to 10.5 v
The battery is about 18 months old a 120ah and 120 solar.
On our way down to Spain we only used aires fora week and had now problem and the battery performed as it should do

 

[wildebus]

You haven't said what Sargent unit is fitted or what solar controller is fitted, but the sad truth is that the Sargent chargers by and large are very poor at charging the batteries and so looking after them.
You would expect the battery to be fully charged after being on EHU for a fortnight and then the engine keeping it charged, so to be down to such a low voltage would suggest the charging system is not working. But you would possibly have found that out when on site as you need the charger to maintain the battery for all the 12V services (lights, USB, TV, water pump, etc). Maybe the solar was enough to take care of that though?
Only way to know how good the battery is is to fully charge with a proper smart charger and do a load test (with charger and Solar off) o see how long it runs until hitting a set voltage, or over a set time. e.g. put a 6A load (TV plus some lights would be about right) on for 10 hours after battery fully charged and then turn off everything. Battery should be around 12.05V

The other thing is is the Voltage quoted by the Sargent panel right anyway? Have you put a meter on the battery itself to see? I find the voltage stated by the Sargent unit to be pretty inaccurate generally and you might not have any problem with the battery itself at all.

 

[RichardHelen262]

You haven't said what Sargent unit is fitted or what solar controller is fitted, but the sad truth is that the Sargent chargers by and large are very poor at charging the batteries and so looking after them.
You would expect the battery to be fully charged after being on EHU for a fortnight and then the engine keeping it charged, so to be down to such a low voltage would suggest the charging system is not working. But you would possibly have found that out when on site as you need the charger to maintain the battery for all the 12V services (lights, USB, TV, water pump, etc). Maybe the solar was enough to take care of that though?
Only way to know how good the battery is is to fully charge with a proper smart charger and do a load test (with charger and Solar off) o see how long it runs until hitting a set voltage, or over a set time. e.g. put a 6A load (TV plus some lights would be about right) on for 10 hours after battery fully charged and then turn off everything. Battery should be around 12.05V

The other thing is is the Voltage quoted by the Sargent panel right anyway? Have you put a meter on the battery itself to see? I find the voltage stated by the Sargent unit to be pretty inaccurate generally and you might not have any problem with the battery itself at all.

It is the Sargent ec500
The solar is going through the Sargent unit
It all worked perfectly on the way down even staying on an aire for two days without ehu and that was using lights, tv and shower inc the extractor fan and blown heating,
I have put a meter on the battery and it is showing the same as the Sargent 10.5v .
This was within a couple of hours of coming off ehu and nothing switched on.
I will buy another battery today and see how that goes on, fingers crossed it is just premature failure of the battery.

This is the battery I have fitted at the moment

 

[RichardHelen262]

The sun has been out for a couple of hours now and the battery is back up to 11.9v

 

[RichardHelen262]

After just another 15 minutes it is up to 12.5v and the sun is still low this seems to be charging very quickly considering the sun is low and only 120 solar

 

[Glandwr]

A totally dead battery can show 12v plus across the terminals IF it is connected to a charger of any type that is working. The only accurate way to check is after dark and with no other input.

 

[barryd]

No expert but it sounds to me like the solar is working as is the engine in charging the battery but your EHU is not charging it. If that was the case it probably would be ok driving down aire hopping but once in situ for a week if its maybe only being getting charged from the solar when it should have been charging from the EHU this could be why its depleted over time. Maybe get a meter on it when you plug the EHU charger in when its low. See if it suddenly goes up or not.

 

[wildebus]

After just another 15 minutes it is up to 12.5v and the sun is still low this seems to be charging very quickly considering the sun is low and only 120 solar

When a battery has lost capacity it will both discharge AND recharge much faster as it is reacting as it if were a smaller capacity battery.
It is quite a common thing and there is a tendency for people to think not that the battery is bad but their charger has suddenly become very good!

 

[RichardHelen262]

When a battery has lost capacity it will both discharge AND recharge much faster as it is reacting as it if were a smaller capacity battery.
It is quite a common thing and there is a tendency for people to think not that the battery is bad but their charger has suddenly become very good!

This is what I was thinking I shall go and buy a new battery.
Thank you

 

[maingate]

This is what I was thinking I shall go and buy a new battery.
Thank you

Before you buy a new battery, try this.

I had a similar sort of problem and it happened because my solar controller had developed a fault. See if you can borrow a test meter, set it to DC volts and check the output from the solar panel to the controller and the voltage coming out of the controller. If the input is in the low twenties, the panel is OK. There should be an inline fuse between the solar controller and the Sargeant (a system I am not familiar with). Remove the fuse and using the meter check the voltage out of the solar controller to the Sargeant unit.

You will be very unlucky to have bought a faulty battery (unless you have abused it), that's why I think the fault could be elsewhere. If possible you could just remove the above mentioned fuse and leave it out if you are travelling and see if the alternator boosts your voltage up to where it should be. That would indicate a faulty controller or possibly a sargeant fault.

What I have said might sound complicated but it will only take a few minutes and is easy to do. I believe batteries are more expensive in Europe and it might save you spending money but still having the problem.

 

[AllanD]

Have you checked the battery terminal connections are properly tightened?

 

[molly 2]

My old LB failed last year 2x110 amp led acid ,I changed to 1 lead carbon 110 amp , it has served my needs over 16 months . The controller in my 328 sargent is a very cheap pwm . But it dose top up engine battery as well so a bit of a pain to swop for mppt .

 

[RichardHelen262]

Update

We found a guy close to where we stayed last night that does camper van conversions and repairs
He spoke perfect English
He only had one battery in that he had bought for a conversion he was doing so let me buy that and fit it,
He did put his meter on and did some checks
When he put his meter on the battery it showed 12.96v then he had me switch lights on and I only managed to switch one led light on straight away it fell like a brick straight down to 10.5v the battery is only 100ah and is a agm which isn’t ideal but it will do for now

 

[wildebus]

Update

We found a guy close to where we stayed last night that does camper van conversions and repairs
He spoke perfect English
He only had one battery in that he had bought for a conversion he was doing so let me buy that and fit it,

He did put his meter on and did some checks
When he put his meter on the battery it showed 12.96v then he had me switch lights on and I only managed to switch one led light on straight away it fell like a brick straight down to 10.5v

I presume the above is the original battery? the voltage drop sounds like a cell has failed?

the battery is only 100ah and is a agm which isn’t ideal but it will do for now

Battery warranties can be tricky things as a lot depends on how they were treated, both by the user AND the charging system, but it is worthwhile if you have the space to keep the old one and see if it is a manufacturing fault when you get back to the UK.

 

[RichardHelen262]

I presume the above is the original battery? the voltage drop sounds like a cell has failed?


Battery warranties can be tricky things as a lot depends on how they were treated, both by the user AND the charging system, but it is worthwhile if you have the space to keep the old one and see if it is a manufacturing fault when you get back to the UK.

I bought the battery from Alpha batteries about 18 months ago, I will contact them when I get home,
If they say no it isn’t the end of the world