Leisure Batteries - again

[Guest Tracker]

My Leisure batteries are one Elecsol and one Moura, both 110 ah the first about 20 months old and the second 15 months old.

 

They are linked by 30 amp cable and fuses and soldered joints (I know, crimped would have been better!)

 

The alternator charges at 14.4 volts and the regulated solar panel charges at a similar rate even on a dull day.

 

Before use I top the charge up with the inbuilt charger which only charges at 13.8 volts, but even so should surely put something back?

 

When on charge they do show up to 13.0 volts so I assume that a charge is going in?

 

When fully charged and even after a four hour drive the batteries never show more than 12.6 volts which mean that with diesel heating they struggle to last two nights and on previous vans I have got up to four nights in winter and a lot more in summer from twin batteries.

 

It seems to me that they appear to be getting a full charge but they are incapable of storing it?

 

I am happy to buy two new batteries if I need to as this aggro is more trouble than it's worth (Varta 81310 are favourite at the moment) but before doing so I wonder if those more knowledgeable than I might have any thoughts please.

 

Unfortunately although both batteries were supplied new they came under different van warranties from different dealers so I don't have receipts - but at least I didn't pay for them!

 

Interestingly the Elecsol weighs 25.5kg and the Moura 23.9kg whereas the Varta is shown as 29.5kg - does more weight = more lead = more power = better durability?

[lennyhb]

13.8 v is normal max voltage for a leisure battery charger in a Motorhome they are set at 13.8v to avoid any possibility of the batteries gassing when left permanently on charge, so you can never achieve a full charge from the in built charger.

 

I would disconnect each battery in turn check the voltages you may find that one has a duff cell & dragging the good battery down, you could also carry out charging tests on each battery in turn.

 

If you find one battery is duff it is still best to replace both at the same time.

 

Regarding the warranty on the batteries you may not have a receipt, but what about a credit card or bank statement showing payment? Also the batteries should have a manufactured date on them so decent dealer would replace without a receipt.

 

 

[spospe]

Tracker

 

Battery technology is not a perfect thing and variations between batteries of the same make and size are quite normal, so variations between different makes are only to be expected.

 

More weight probably does mean more lead, but this is not necessarily a good thing, because it all depends on how that weight is used. Originally batteries had plates of solid lead (usually called Plante batteries) and these were both heavy and of relatively low capacity, due to the restricted surface area. Later developments led to the battery plate being made of a kind of lead paste, which increased the surface area and thus the capacity, at the expense of plate life (they tend to crumble and the resulting debris falls to the bottom of the cell and eventually shorts the plates out).

 

The answers to your questions are ....

 

a) Perform a capacity test of you existing batteries to see exactly what state they are in. Use a known load, for example, the fan on your diesel heater, or some lights and time how long the battery will support the load before the voltage drops to 11.5 volts. Better would be to use a hydrometer, as this gives a more accurate measure of capacity, but I am guessing that you might not have such a device, or maybe unwilling to prise the top of a 'sealed' battery. My advice is that when a battery drops to 70% of its rated capacity it should be changed. So first use a battery charger (not the on board 12 volt unit) to fully charge the batteries to a maximum of 14.7 volts for lead-acid or 14.4 for gel and then carry out the above test.

 

b) If changing, always use batteries of the same type and capacity. Do not mix lead-acid and gel. Always replace batteries at the same time.

 

c) Soldering connections is a perfectly good way of joining cables if done correctly. Crimping was introduced for speed and simplicity. Best of all crimp and then solder the crimped joint.

 

d) The on board 12-volt power unit will never fully charge the batteries. It will put a useful charge into them, but as it cannot reach, the 14.7 volts (lead-acid) or 14.4 volts (gel) needed for 100% charge there will always be some space for a bit more. Likewise, the alternator cannot fully charge either the starter, or the leisure batteries. You need a sophisticated charger, such as one of the CTEC units to do this, (some of the solar panel chargers are OK in this respect).

 

This is a complex subject and it is difficult to give a short, comprehensive reply, if I have missed anything, ask again.

 

[Guest Tracker]

Thanks guys.

 

They are both on the bench on charge with a Halfords 'intelligent' (allegedly!) battery charger but before charging and after standing for two days with just the solar panel putting in a little in the dullness of short February days they were both showing around 12.5 volts even after an hour or two standing on the bench uncharged and unconnected.

 

I don't have any receipts because I didn't pay for them!

 

I am cosidering a 'drop' current / voltage test at the local battery 'specialist' but will that tell me what I need to know or will it just give me an idea of their engine starting ability which may or may not help me?

 

I must confess to finding it a fascinating subject so please keep it coming - how sad is that!

 

Thanks.

 

[spospe]

Tracker

 

The usual battery test equipment that folk in the garage trade have is just for starter battery use. I have never seen a specific tester for leisure batteries and my personal method is as described in my earlier post i.e. use a load which is representative of the load you would use in the van when you are away and time this to the 70% discharged point (after making sure that the batteries are fully charged).

 

From what you are saying, it does sound like your batteries are gracefully on the way out (i.e. a slow fail and not a catastrophic sudden fail).

 

Using our van as we do, for between 120 and 150 nights per year, I expect leisure batteries to last about 3 years, anything more is a bonus.

 

Do not belive in 'no maintenance' lead-acid batteries, they all need topping-up, usually twice a year at our rate of use. Make sure that you use either distilled water, or water from a soft-water area.

 

[colin]

My money's on the Elecsol being duf.

[Guest Tracker]

Currently they are both on charge in parallel and after about 4 hours charging the voltage going in has risen from 13.3 to 14.4.

 

I'll leave them on charge until the charger says that they are fully charged and goes into maintainence mode at which point I will check the separate voltages again then disconnect and leave for 24 hours before checking individually again to see which has lost what.

 

I hope that this detail will help others who find themselves with leisure battery concerns and once again I thank all contributors.

 

I also emailed both manufacturers describing the problems and I await with some interest their response - if any?

[Brambles]

Tracker, The varta you have suggested is a good battery, but take a look at the 90 Ah offering, its is actually a better battery and with having solar panels will consume a lot less water if repeatedly fully charged.

The capacity at 90 Ah is comarable to the batteries you have when new.

Just because it says 110 does not mean 110 Ah. might be at C/100 rating but sure ain't at C/20 industry standard. The 90 Ah will cope better with deep discharging as well and have longer life...hence why slightly more expensive than the 110 Ah.

(the 90 Ah is Calcium technologgy and the 110 is hybrid)

http://www.varta-automotive.com/fileadmin/templates/downloads/en/Folder/Folder_hobby.pdf

[Brambles]

Tracker, what model/number is your Moura battery please?

You might (probably) have a complete mismatch between your batteries and this will not have done them any good.

[Guest Tracker]

Jon,

 

The Moura is model 0191 plus and the Elecsol does not have a model number except to say that it is carbon fibre and your theory of incompatiblity is interesting as both batteries appear to have charged well.

 

Charging finished late last night at which time the Elecsol showed at 12.94v and the Moura 12.91v as soon as the charger switched off. Withing two hours they were showin 12.89 and 12.87 and after a twelve hour rest they both at 12.79v.

 

That seems to me to be about right for fully charged batteries but I will see how they look in another 24 hours.

 

I had a reply from Elecsol suggesting that a cell equalisation charge may be needed. I have never heard of this - any thoughts anyone please?

 

So it might not be the batteries after all?

 

But if I do need to change one of them which one would work well with the Varta you linked to as that seems to be of a different type again as it mentions calcium?

 

Many thanks for your help.

[Brambles]

Interesting - so far so good. Come back to this in a minute.

 

Equalisation charge,

 

When you constantly charge and discharge cells they get a bit out of balance and one cell will end up lower than the rest. What happens is the 5 other cells get fully charged and the voltage rises but the poor 6th cell lacks behind and is no where near fully charged. It can be more than one cel lagging behind but because all the voltages added up are greater than 14.4, or whatever your end point volage is, the charger folds back to maintenance charge.

Equalisaton charge is where you apply a much higher voltage (but constant current) and bring the low cells up to fully charged. It also helps desulphate the battery if the sulphation crystals are not too hard.

You can help by leaving on maintentance charge for extended periods, 5 to 10 days should be enough depending on trickle charge rate.

You can usually tell as well if a cell is begining to fail as when bulk charging it will gas a lot more before the other cells. Also look in the caps for dark grey or dark brown deposits..usually a sign of overcharging or sulphation (brown). The acid shoud be clear and not have bits of brown floating in it - sulphated lead, or grey bits - lead.

 

So now you know how to equalise, extended trickle charge, or a proper job by increasing the charge voltage which really needs a proper equalisation charger.

 

Your voltages seems fine, but next step is to do a discharge test. A known load for x hours and see how much the batteries drop in volts at end of test. Alernatively see how long it takes for the voltage to drop to 12.4 volts. Test each battery separetly.

 

Now another problem you can get with batteries is stratisfication of the acid, If you are never getting any gassing the acid never gets mixed and the acid tends to concentrate more at bottom of battery. So at 13.8 volts max, you wil eventually get acid stratisfying but I doubt you have that problem if driving occassionally because of movemnet and the alternator is 14.4 volts, but it could happen in one cell on its own if it is lagging behind the others never getting fully charged and gassing.

 

 

[Brambles]

Ahhh! you mentioned linking with the Varta.

Yu reall shoudl stick to similat technology. I think the Moura is calcium (-ve plate) silver (+ve plate), I will need to check if I can find it but most Moura batteries are calcium silver. The Varta 110 Ah hybrid is Calcium Antinony, and the 90Ah Varta is Calcium Calcium.

I am not sure of comsumption of calcum silver of the top of my head but do know they have lower internal resistance and higher charge voltage (14.8)

Calcium Animony is 14.4 volts.

Calcium Antimony ( suspect that is what the Elexsol is) is classed low maintemtance - in other words it does usesome water.

 

Calcium Calciium uses very little water and is classed Zero mainitenance as teh reserve of acid wil last the life of the battery when charging at 14.4 volts max.

They all have different charge and discharge characteristics so should not be mixed in paralled.

If forcing me for an answer and you really want to pair up, I would say varta 90 Ah with the Moura, and the 110Ah with the Elecsol.

However I would not do this so in a way teh answers are immaterial, I would buy two new batteries and I would go for Calcium Calcium or Calcium Silver. Calcium Calcium is 1st choice although I would go with silver if doubling up as a starter battery (e.g. a boat)

 

A pair of batteries should be traeted as just that, if one dies after the 1st year of use , then both need replacing.

I had a pair of batteries at work years ago and one died after 6 months (lucas), the supplier replaced both as bought as a pair to use as a pair. I am not sure how many suppliers would do this though.

 

[Guest Tracker]

Thanks Jon.

 

I don't have any easy way of charging at high volts so I will have to settle for an extended trickle charge with the automatic charger.

 

Before I do that I can do a discharge test. I have a bank of 3 x 12v 21w bulbs set in parallel so that is a known 63w or 5.25 amp discharge.

 

Should I run that for say 4 hours and see what happens?

 

Before starting perhaps I should give each battery a good shake to stir up the acid although neither have ever been topped up - the Moura being semi sealed and I have not been able to get the top off with reasonable force - and I don't want to resort to unreasonable force just yet!

 

 

The Elecsol label just says 'carbon fibre monobloc' with no other useful info. The Moura label says' intelligent battery silver alloy sealed for life'.

 

Does that tell you anything more?

 

I am loathe to buy two new batteries when both of these seem good but I can see where you are coming from and if that is what I have to do to make the van usable in winter then so be it!

Thanks.

[Brambles]

Tracker - 2010-02-10 2:34 PM

 

Thanks Jon.

 

I don't have any easy way of charging at high volts so I will have to settle for an extended trickle charge with the automatic charger.

 

Before I do that I can do a discharge test. I have a bank of 3 x 12v 21w bulbs set in parallel so that is a known 63w or 5.25 amp discharge.

 

Should I run that for say 4 hours and see what happens?

 

Before starting perhaps I should give each battery a good shake to stir up the acid although neither have ever been topped up - the Moura being semi sealed and I have not been able to get the top off with reasonable force - and I don't want to resort to unreasonable force just yet!

 

Thanks.

 

Yes to above discharge test... Do each battery seperatly.

No do not sake batteries - just et the gassing when on charge mix teh acid. If you think one needs mixing, then rock it sideways gently and slowly and it will mix acid. f you str up the lead fallen to botton of cells it can end up shorting the cells out and killing the battery - so no shaking and trat battery ike a bomb. Supplier are criminal they way the thump a new battery down on the sales counter!

 

Problems finding a spec for the Moura, I think it is a standard Calcium Silver starter battery type 019. (019 is a industry standard 100Ah starter battery) I need a number like Mxx110xx. Anyone speak portugese as in Brazil.

 

p.s. Going back to putting my Fiamma extractor fan back in Van - had it all in bits for cleaning...looks like new now, apart from filthy frame still attached to roof which I will clean now and try not to drip stains on the carpet.

 

[Guest Tracker]

Thanks - all understood!

 

The only references on the battery itself are >pe/pk< on the end casing and UEO2060 stamped on the top of the casing.

 

There are others on the labels but these may just be label references?

Anyway they are UBE5592, UBE3210 -A-PK, and UBE3204-A-PK.

 

Any help? I really appreciate your help on this Jon - many thanks.

[spospe]

Tracker

 

An equalization charge, as the name implies is used to bring all cells of a battery up to the same level (make them 'equal'). In order to do this, the normal practice is to charge the battery at a higher than normal voltage, typically 14.7 volts for a lead-acid and 14.4 for a gel type.

 

The charge is maintained until each cell reaches the same voltage (2.45 for a lead-acid and 2.4 for a gel) and is then held steady for 2 hours so as to allow all 6 cells of a 12-volt battery to 'equalise'. This gives the maximum possible state of charge and should be the starting point for any tests and / or decisions about replacement.

 

Of course, in order to carry out an equalization charge, you must be able to get at the connections for each cell of the battery and this is often not possible with modern enclosed construction.

 

Batteries are rated at so many Ampere Hours (A/H) capacity at a specific discharge rate and this is often quoted as being the "I" rate. For example, a normal leisure battery would probably have its capacity of say 110 A/H stated at the I20 rate. This means that if it is discharged at a constant load over 20 hours, it will yield 110 A/H. To do this it would have to have a load requiring a current of 5.5 amps.

 

The above is a little simplistic as it assumes that the battery will be totally discharged and normal practice recommends only discharging 70% maximum, in this case the time at 5.5 amps would be 14 hours.

 

Loading a battery to more than its quoted "I" rate will give a lower apparent capacity and using a lower rate will yield an apparently higher capacity.

 

Cold will reduce apparent capacity, so having the batteries inside the body of the van will maximise their capacity, especially for winter use.

 

 

 

 

[Guest Tracker]

Just to add to the confusion, whilstout with the dog, I spoke to a chap with an elderly KonTiki on his way to Ireland this afternoon and batteries came into the conversation. He reckons that he has two x 110ah Numax leisure batteries and they have served him well for nearly three years and are still charging and lasting well.

 

I know what has been said but buying two Numax locally would save me a hundred quid on the Vartas?

[spospe]

I may be a Philistine, but I have always bought batteries on price and a saving of £100 sounds like a good argument to me. If they last a year less than another make does that matter? I would say that the savings made up for any shortening of life and in practice, given good maintenance, ‘cheap’ batteries have lasted me as well as dearer ones.

 

Good maintenance equals a) keeping them charged b) doing equalisation changes (solar panel regulator does that for me) and c) keeping them topped-up with distilled water (remember low-maintenance does not = no maintenance)

 

[Guest Tracker]

My thoughts exactly Michael!

 

I've just found a 'Minicraft' model making power tool transformer with voltage output at 1 amp variable etween 12 and 18 volts on the dial although the no load output on full is around 24 volts.

 

The solar panel I know charges at up to 14.7 volts because I've seen it showing that so would the Minicraft transformer work if an equalisation charge is needed or would the solar panel have achieved this on one of the (very few) bright sunny days of the winter?

 

It does not alter the issue that with the batteries insitu the voltage is never above 12.6 at most and the real issue is whether it is

 

1] failing battery(ies) which looks unlikely given the way they have invididually bench charged and are holding charge at 12.79V so far.

 

2] battery incompaibility - something I don't fully understand why it should happen?

 

3] self discharging or by way of hidden use or leakage whilst in situ on the van - although meter showed about 100 millivolt discharge the solar panel at 60 watts is surely up to covering that?

 

4] none of the above - in which case - what?

 

Confusing innit!

[Brambles]

Tracker, The Numax L110 I believe is made in South Africa, probably Willard Batteries part of the Power Tech group. It appears to be a very reputable battery. Numax name is owned my Manbat in the UK who import and distribute under the Numax branding. It is always difficult to know who supplies are as they will keep fairly secret and may change suppliers at times.

If you can save £100 this represents very good value, I am surpised you can save that much but then do not know what price you are on the Varta.

Tayna have the Varta 110 at £112 Approx.

and Numax L110 at £75 Approx

If they last half the time, weighed up with the risk of murdering a battery prematurely I have to agree with spospe - why spend more. Got to be better than your Elecsol!!!

[lennyhb]

Rich,

 

Looking at your posts you have only been checking the voltage.

 

Have you checked the current draw on the batteries insitu, there may be nothing wrong with the batteries and something is drawing current. Something left on that you have overlooked or a faulty bit of kit somewhere.

 

I would put one of the batteries back in the van & connect an ammeter is series with it, depending what's live with the control panel switched off I would not expect much more than 50 - 100ma.

In my van there is the dump valve on the Truma boiler, Sat receiver in standby & the cab Radio/DVD in standby all live with the panel off.

 

 

 

 

 

 

 

 

[Guest Tracker]

Jon,

 

The 90 ah Varta Hobby you highlighted is about £125 and all are subject to carriage of between £12 and £14 each.

 

The local motor factor who also recommends Numax - not least because he sells them I suspect - has quoted me £155 for two Numax XV31MF 110ah for local collection just down the road from home - so no carriage charges - plus I do like to buy local when I can.

 

But first I need to be sure that I need them and the problem is not elsewhere?

[Guest Tracker]

Lenny,

 

Thanks for your input.

 

I did a leakage / 'all off' test last year and found about 100 ma draw which I put down to the Sargant control and dispaly panel and anything else electronic maybe permanantly wired in.

 

At that time I felt that the 60w solar panel at say 50% efficiency for say 7 hours a day - about 17.5 ah per day - should more than compensate for this 2.4 ah per day- but I will check again. Or are my calculations wrong - I'm no expert as you've probably gathered!

 

The water dump valve is manual, the sat nav is a separate Tom Tom, the cab radio has an isolating switch which means that I have to enter the code each trip but it draws nowt when idle!, the status signal booster is off and the TV also has an isolating switch and I always switch the control display panel off too!

 

Have I missed something anyone?

[lennyhb]

Rich,

 

You say you did a check last year but has something go to pot since then probably worth doing another test before prising the wallet open.

 

 

 

 

[spospe]

Rich (Tracker)

 

You posted this above:

 

"At that time I felt that the 60w solar panel at say 50% efficiency for say 7 hours a day - about 17.5 ah per day - should more than compensate for this 2.4 ah per day- but I will check again. Or are my calculations wrong"

 

Your calculations are over-optimistic for this time of year as the daily output of a 60 watt solar panel will probably (depending on the orientation of you van and the amount of shading the panel gets) not exceed 4-5 ampere hours of effective input to the battery per day. Indeed, on some of the dull days we have had recently 2 A/H would have been the best you could have expected. The energy that a panel produces at any time of the year falls off dramatically at both the start and end of the day. With a flat mounted roof panel you can forget the first and last 2 hours of the day from the point of view of getting any worthwhile charge, so this only leaves you from about 10am to about 3pm (approx) at this time.

 

The solar panel can do a good equalizing charge during the late spring to early autumn months, but there is too little sunlight (too low and too short) right now for it to be effective at rescuing a suspect battery. The panel can maintain a properly charged battery at this time of year, but not charge it from a discharged state.