Battery

Hi my  motorhome .has been at the dealership  since the start  of lockdown  .have been monitoring  the charge on the  batteries.  Both saying 12.2 volts. Never gone  above this could someone  tell me how far off fully charged are they.they did both go  flat at some point. So would they be damaged.  Should  I ask for new ones under the warranty

It will vary a bit depending on the technology of the batteries but fully charged and rested for several hours after charging they should read 12.6-12.8v. 

12.2v indicates around 50% but this only applies if the battery is under no load at all so are the batteries connected up or are you using a DVM. It does not take much load to bring the terminal voltage down to that value even if the SoC is 100%

The voltage is no indicator of a "damaged" battery. At 12.6v it would indicate a battery is fully charged but it could be that the overall capacity is significantly reduced. As has been discussed here many times it is quite hard to really assess the condition of a battery if all you have to go on is voltage.

Thanks for the  reply the  lesiure battery  must be keeping the alarm going and the tracker not sure what the engine  battery  would be charging.if it is not plugged  into electic then the 80 watt solar panel would be charging  the batteries.  Would this keep them to 12.2 volts only

On our Broadway the solar panel keeps both batteries well above the 12.7 nominal voltage during daylight hours (alarm but no tracker). Assuming enough daylight is getting to the panel and that the meter isn’t faulty then something is wrong. Certainly if the batteries have been completely discharged then I’d be worried but at 50% it’s difficult to prove damage. Worth a try though. It depends whether your dealer can back-charge to AS as a warranty claim.

It does actually depend on what the sun is providing at the time as well as what loads are active. The vehicle does draw from the starter battery even when off, it depends how long after turning off the ignition you take the measurement. 

The only reliable way is to disconnect the battery and then leave them for at least several hours. I certainly would not depend on the rather dubious Sargent readout.

BornAgain wrote:On our Broadway the solar panel keeps both batteries well above the 12.7 nominal voltage during daylight hours (alarm but no tracker). Assuming enough daylight is getting to the panel and that the meter isn’t faulty then something is wrong.

its not keeping the batteries that you are saying above 12.7 its the solar charge going into your battery and will show up to 13.6 and 13.8 on a float charge and on a boost up to 14.6 and 14.8. as H/F has said is how to test a battery and do not trust the sargent control  read out and a volt meter will not tell you if a battery is now holding its full amp capacity as to the battery condition

Mids wrote:Hi my  motorhome .has been at the dealership  since the start  of lockdown  .have been monitoring  the charge on the  batteries.  Both saying 12.2 volts. Never gone  above this could someone  tell me how far off fully charged are they.they did both go  flat at some point. So would they be damaged.  Should  I ask for new ones under the warranty

I have just had the same problem with my van been at A/S workshop from 1 dec 2020 and damaged my batteries and my vehicle battery has been tested by Peugeot and needs replacing and is getting done under the 2 year warranty as for my leisure just another problem to sort with A/S. when you leave your vehicle with the dealer its now in there control to make sure items like the batteries are kept to a safe charge and not let them become damage as its sound like yours have done as well

This is my panel showing good voltage as this is the voltages from the solar going into the batteries but the vehicle battery has been tested with a cca meter and is faulty and needs replacing[You must be registered and logged in to see this link.]

Glyne/HF what is the easiest what to see 'how healthy' a battery is. Agreed, it might be reading 12.7+ volts but may have seriously diminished capacity...
Is it a controlled 'drop test', connecting a known load for a known period? Is this, in effect, what the CCA test does?

bolero boy wrote:Glyne/HF what is the easiest what to see 'how healthy' a battery is. Agreed, it might be reading 12.7+ volts but may have seriously diminished capacity...
Is it a controlled 'drop test', connecting a known load for a known period? Is this, in effect, what the CCA test does?

You can test all the old ways from in the past drop test load test may show as ok but now is done with a cca meter you test the battery if says replace you have to put on charge then retest after the battery has settled and if it still says replace and shows the amps as well below what it should be clearly is not holding its full charge

Traditional Drop tests are very much NOT recommended by most battery manufacturers, if nothing else we would do it with the cell caps off and stop as soon as some cells started to bubble. Not possible with sealed batteries.

Modern digital testers leave a little to be desired but are the best "instant" readout however pro ones are £1k+

The alternative is to fully charge the battery off the vehicle then apply a known load of 5-10A for enough time to drop the capacity to at least 80% (for the spec of the battery), rest the battery then meter it.

Most batteries capacity is quoted at the 20hr rate so for a 100Ah battery that would be a 60W headlamp bulb for 4 hours.

Agree with HairyFool, there is no simple and reliable test for a battery except applying a load for a timed period. If you have the time and inclination you can leave it unconnected for a few weeks and see if it holds its voltage.

BA makes a good point as when a battery deteriorates one of the effects is internal leakage goes up. 

A New, good battery should only lose around 10 to 20% charge from full if left off charge for 6 months. This gradually reduces in time with age.

Mids wrote:Hi my  motorhome .has been at the dealership  since the start  of lockdown  .have been monitoring  the charge on the  batteries.  Both saying 12.2 volts. Never gone  above this could someone  tell me how far off fully charged are they.they did both go  flat at some point. So would they be damaged.  Should  I ask for new ones under the warranty

Are we in EC700 territory.

The fact that you can monitor both batteries indicates that the EC700 is on, it may or may not be set for "Smart Charging". So both Batteries are indeed under some Load.

12.2 Volts on both batteries are the mysterious levels that you get when the Solar charge is not coping. Regardless of the "Smart Charge" there is a 'leak' path between the two batteries admitted by Sargent but not explained. Neither can I explain it with the circuitry details available but I can prove that it exists.

I spent 3 months in Spain with the original Solar controller, both Battery Voltages always started to equalised overnight to 12.2 Volts obviously with the 'van in use the EC700 was on. When this point was reached I either went for a drive to recharge or to a site with EHU. Hence I didn't encounter any of the Alarms below.

Maybe the Dealer is relying on these alarms to 'protect' the Batteries.
Whilst this 'high tech' system may work when the 'van is in use for Leisure Loads its hardly suitable during storage.


Leisure battery voltage low
With control panel power on and leisure battery selected (as active battery) and the voltage level falls below 10V Message on screen and 60 second audible beep.


With control panel power on and leisure battery selected (as active battery) and the voltage level is below 9V Message on screen and 60 second audible beep. If no action taken after 30 seconds then the system will switch the power off to prevent severe discharge of the battery.


Note: This is an emergency cut off level to protect the battery from severe damage. You should not rely on this cut off level during normal operation, but manage your power consumption to a discharge level of 11.5V or above.
This cut off only applies to power drawn from the battery by the leisure equipment that is controlled by the control panel power switch; it will not protect the battery from discharge by permanently connected equipment. 


If the vehicle battery is selected instead of the leisure battery, then similar warnings to those described above are applied to the vehicle battery. The vehicle battery low warning level is 10.9V.
Vehicle 10.9V Battery selection is changed from Vehicle battery to Leisure battery. If the leisure battery is below 9V then a further warning will occur.


This cut off level is designed to protect the vehicle battery from over discharge. The 10.9V level ensures there is sufficient power in the battery to run the vehicle electronics and start the vehicle.
This cut off only applies to power drawn from the battery by the leisure equipment; it will not protect the battery if you leave vehicle circuits switched on, such as the road lights.

Since you say both Batteries went flat at some point the dealer must be putting the 'van on Hook Up at times, since leaving it with the just the Solar charge and the EC700 on is just leaving it for both Batteries to go flat.

My solar panel has just taken control  of charging , both batteries  fully charged ,  had it plugged  in on a timer for 1 HR a day  that worked well , van is parked in full  shade all winter ,

Chris
After a good charge from the solar today and testing with the up to date equipment even with a good voltage shows replace as to the low amps[You must be registered and logged in to see this link.]

Thanks Glyne, are these photos saying that the battery 'should' be at 680 but is now only giving 473?....so,it's lost 30% of its capacity?

bolero boy wrote:Thanks Glyne, are these photos saying that the battery 'should' be at 680 but is now only giving 473?....so,it's lost 30% of its capacity?

if you look at the voltage you think its 100% full and yes it should be over 680 cca so you cant think a battery is ok because the voltage looks ok .this is my own battery that needs replacing and is getting sorted under warranty

The two values are for Cold Cranking Amps which is the current it would deliver before the voltage dropped below a set value.

The problem is the tester does not actually run that test but loads a much smaller current and targets a higher voltage and for a very short time. It repeats the test a number of times then extrapolates the results to create the displayed result. What it actually detecting is increases in cell resistance not a reduction in capacity and one does not necessarily follow the other. The tested battery might still be fine as a habitation battery, only a capacity test would show otherwise.