Banner Battery Capacity Issues

[mrbigfeet]

Has anyone else had cause to question the amount of electricity that gets stored in their Banner Battery? I have a 115 ampere hour Energy Bull fitted to my caravan. I also have a 150 watt solar panel and charger fitted as I prefer to be on non electric sites. This should ensure a continuous good state of charge. I also have a CTEK 10 amp charger and used it on the battery twice during the first year. At the end of year 1 I removed the battery from my caravan and measured 80 ampere hour capacity. I contacted the supplier and was told this was normal for a 1 year old battery and the battery had not failed for warranty purposes. I continued to use the caravan under the same conditions and at the end of year 2 I measured 55 ampere hour capacity. I again contacted the supplier and and got the same response. I then left the battery on my garage bench for 9 months. I recharged it in "recond" mode and again got 55 ampere hours. I am currently being told that I have not used the battery correctly. What is correctly?

[Derek Uzzell]

Welcome to the Out&AboutLive forums.

 

Banner “Energy Bull” batteries come in three different types - gel, AGM or wet-acid.

 

I’m guessing that your battery is wet-acid type and the "959 01” product that has a quoted (K20) capacity of 115Ah. The 959 01 battery is described here

 

http://www.bannerbatterien.com/backend/datasheets/EN/010959010101.pdf

 

and perhaps you could confirm that this is what you have.

 

It would also be helpful if you could say how you are measuring your battery’s Ah capacity and confirm that the battery’s electrolyte level has always been regularly checked and topped up when necessary. Wet-acid Energy Bull batteries are far from maintenance-free and water ‘loss’ can be significant even in normal use.

 

I’m doubtful that a simple answer can be provided on this forum to your “What is correctly?” question. If I were in your position I’d be asking whoever is currently telling you that you have not been using the battery correctly to justify that statement.

 

(For what it’s worth, my Rapido motorhome is fitted with a wet-acid Banner Energy Bull 957 51 100Ah (K20) battery and Rapido ’s User Manual advises an expected lifespan for that battery of 3 years.)

 

 

[Tracker]

This is an interesting topic that affects many people and it would be good to see how a different battery, perhaps the tow car one, measures up for capacity if only as a comparative exercise as I doubt the issue is restricted to Banner alone?

 

Perhaps details of the device used to ascertain battery capacity could be given in case anyone else has experience of similar devices?

 

Leisure batteries seem to me to be the weak spot of many vans and caravans with much misleading hype and much misunderstanding from owners?

 

This seems to be often due to inadequate handbook instructions to owners, or from converters in the way the charging regime is set up and applied in construction, and from battery and charger suppliers who appear content to sell their wares without worrying too much about how it is set up and used?

 

We seem to have the situation where vans are designed to be on a mains hookup where that alone tends to mask the system inadequacies that off grid camping quickly highlights.

 

 

 

[aandncaravan]

It is normal for batteries to lose capacity as they are used. This occurs for two primary reasons.

 

The first is that every time a battery is charged and then discharged some of the material used during the chemical process does not convert back to Lead.

This is something that occurs in most Lead based batteries.

 

The second is 'Wear and Tear' caused by general deterioration, like corrosion, damage from over charging, discharging very deeply, etc.

 

So the Battery retailer is right, it will lose capacity over time. Except that yours does sound like it might be losing more than most?

 

Battery warranties generally only cover 'failure' from a manufacturing defect. Not from deterioration, which will happen naturally but which can be accelerated by heavy use.

 

I would suggest that his 'Correctly' is anything that he can apply to avoid giving you another battery??

 

Most battery manufacturers say that for optimum life, and maximum capacity during that life, you should discharge the battery to no more than around 12.5v (depending on technology). That both the current you take out and the current you put in should be no greater than about 20 amps, although 30amps charge/discharge can be acceptable for short periods.

 

To give you an idea how usage affects life, the Victron Energy Long Life Gel battery will give 4,500 cycles if you only discharge down to 30%, or about 12.6v.

If you discharge so only around 20% power is left (80% DOD, at around 12.2v) you will lose 3,000 cycles.

 

In broad terms, the more you deviate from the above guidelines, the greater the loss in capacity while you are using those cycles. In other words, as you have discovered the shorter each useful cycle in terms of power.

A heavily used battery can be down be down to 50% capacity within two years. It may still hold it's charge and behave perfectly normally, it will just act like a battery half the size.

 

When a battery manufacturer quotes the cycle life, it is normally 'useful' cycles, not 100% of the batteries capacity. With some batteries the final cycles in a batteries life may be 25% of what it delivered when new.

 

Yuasa batteries, on paper, have a lower number of cycles than say an equivalent Banner, but they are generally 'fuller' cycles and close to 100% capacity.

Some manufacturers quote a cycle as an operation where the battery will charge up and then give back some power, even if the power it gives is only a few Ah.

 

 

 

.

 

 

[mrbigfeet]

I am just a normal caravanner with concerns about the quality of the batteries we are being sold. I am concerned that maybe nobody knows how to treat a battery "correctly" in caravan and motor-home use. This means that we can be told and sold anything without a comeback. I think it might be useful if campers related their experiences so that others might benefit. As such, my experience is detailed below.

My battery is a Banner Energy Bull 115/135 959 01. I bought it in January 2014. Because of my previous experience of short lived caravan batteries, I did ask the supplier and Banner as to how I should look after my battery in my situation. I received no definitive answer other than to keep it charged up. My caravan has all led lights, a motor mover and an led tv. My solar charge controller is of the mppt type with a remote control panel that has a display. I was thus able to monitor the battery voltage during use. I can also see charge and discharge currents during use. This is how I can monitor the state of the battery. During a normal day, with no mains hook up the voltage read 13.8v; this represents continuous float charge from the solar panel. I use the mover once on arrival at site and once when leaving site. Each time only for a few seconds. I know that this energy was quickly replaced because I saw the voltage back at 13.8v. My lights are used for 3 to 4 hours a night and the tv maybe 1 to 2 hours a day. Each day I can see that the battery is recharged because the voltage may read 14.4v first thing but eventually dropped each day to 13.8v.

I do periodically check the water level in the battery and top up if required.

At the end of year 1 I removed the battery to my garage. I fully charged it with my CTEK mxs 10 charger in the "recond" position. I then connected my capacity tester. This is a purchased item that has a resistive load that can be adjusted from 0 to 10 amps and a display. I set the load to 5 amps (roughly the 20 hour rate for a 115 amp-hour battery) and started the discharge. The unit maintains a constant 5 amps until the voltage drops to 10.5 volts (this is the voltage specified by Banner and others as the cut off voltage). The unit then displays the ampere hours removed from the battery. I then immediately recharged the battery. I got a reading of 80 ampere hours.

In year 2 I used the battery in the same way and at the end of the year 2 repeated the capacity test. This time I got a capacity of 55 ampere hours. I repeated the test 2 further times and got the same result.

In year 3 I left the battery on my garage bench. In September 2016 I repeated the test and got 55 ampere hours.

Now, maybe I am doing something wrong but as a normal camper I don't know what it is or what else to do! This is why I say that words like "when used correctly" and "gives more power and for longer" are meaningless unless qualified in some way. For now my opinion is that I might as well buy as cheap a battery as I can because I can't see it lasting any less than the Banner.

[aandncaravan]

Dropping a battery down to 10.5v once will shorten it's life.

 

The attached Exide battery chart shows that battery life will drop from over 1000 cycles to a handful if you fully discharge it? This is a battery that is designed to deep discharge.

The chart shows how discharging a battery no lower than 30% (12.7v) is the ideal for maximum life and a 95% discharge below 12v is the worst..

 

You will also see that the second battery discharge chart, from Yuasa, shows that a VRLA Gel battery like the EXIDE G80 is fully discharged at 11.9v.

Your Banner batteries are conventional so will drop to a slightly lower voltage, but 10.5v is very low.

 

 

I would suggest you have been poorly advised on your method of testing?

[mrbigfeet]

I will take advice. How do you suggest I test the capacity of my battery? Bear in mind that Banner and other battery manufacturers state the rated capacity is what the battery will supply down to that voltage.

[aandncaravan]

The cheapest and easiest might be to fit a Watt Meter (eBay at about £12?). You fit it between the battery and the power distribution/charger unit.

It will then tell you most, but not necessarily all, of the power going into/out of the battery.

 

The units record Volts, amps and Amp hours.

 

 

 

One other point is that when you say the battery is getting back to normal because it quickly returns to 13.8v probably isn't the case? What the display is telling you is the voltage at the battery, not the battery voltage which might be 2volts lower.

As soon as any charger, Solar or Alternator, starts charging a battery it is that voltage you see.

 

 

[veletron]

To test capacity, prob best to fully charge it (eg 24+ hrs on hookup), then apply a C/20 load that removes 50% of the stated capacity.

 

Disconnect mains charger, disable (towel) or disconnect solar panel, disconnect all loads, leave to stand for maybe 4 hours.

 

Using a decent multimeter, measure the voltage at the battery terminals, it should be 12.2V or above for Open Lead Acid. A more accurate reading can be obtained by measuring the specific gravity. it should be around 1.19

 

The battery run-down tests to 10.8V on lead-acid batteries is basically destructive testing - don't do it!

 

The NASA BM1 is a nice bit of kit for AH counting and crude SOC indication (that tries to take load/charge into account). More expensive than A&A's suggestion of a AH counter off email though.

 

Best way to avoid taking your batteries outside their comfort zone (eg below 50% charged) it to fit more of them!

 

Nigel

[Robbo]

veletron - 2016-09-20 7:15 PM

 

The NASA BM1 is a nice bit of kit for AH counting and crude SOC indication (that tries to take load/charge into account). More expensive than A&A's suggestion of a AH counter off email though.

 

Nigel

 

Agree with veletron. I installed a NASA BM-1 to monitor my Banner AGM batteries (2 years old). Think my BM-1 was about £120.

 

And yes, the Banner's were replaced with Varta LFD90 as per Allan's recommendations and all seems to be OK now. Thanks Allan (aandncaravanservices) :-D

[Derek Uzzell]

Just in case it proves significant, it might also be worth confirming the Banner battery’s date of manufacture.

 

An “Energy Bull” battery carries a 5-letter group (eg. CFBDF) next to its negative terminal.

 

The week/year date of manufacture is identified by the initial 4 letters of that group, with A=0, B=1, C=2 etc. The 1st pair of letters identifies the week and the 2nd pair of letters identifies the year.

 

So CFBD would equate to 2513 and indicate that the battery had been made in the 25th week of 2013.

 

(Apparently the 5th letter in the group provides Banner with information identifying the person in charge of the production line.)

 

There is another 5-character group next to the battery’s positive terminal and this identifies the production line and battery make-up.

[mrbigfeet]

My battery date code give week 39 2013 and I bought it in Jan 2014.

I think Tracker nailed it when he said " inadequate handbook instructions to owners". Judging by the different responses to this and other threads on the subject, people have very different views on looking after lead acid batteries. Aandncaravan provided a couple of interesting graphs to support his view. However, what comprises a "Cycle"? I know it means charges but how do you determine when a charge wont happen and what happens to the battery capacity in the mean time? Also, the State Of Charge voltages show 12.1 volts for 50% charged. I have beet told that Banner batteries are 50% at 12.5 volts but I see Banner quote 12.2 volts for a Conventional Battery (vented).

I can see that a Watt Meter can display power in and power out of a battery and that works well when you don't have solar or mains charging connected. But with a charger connected in use, I fail to understand how it can tell you the "condition" of a battery.

Batteries are sold as being able to supply, in the case of a 115ah battery, 5.75 amps for 20 hours. Banner quote this in their technical blurb, see below under Capacity.

http://issuu.com/bannerbatterien/docs/technischerratgebergb12.2014/71?e=0

My method of testing may well be a destructive one but how else is one to properly test a battery? By destructive it surely means "reduces charge cycles" as opposed to "destroys battery immediately"

Another puzzle. If Banner talk of supplying energy down to 10.5 volts, why do Exide talk of 0% charge below 11.8 volts? (see above graphs).

All I'm trying to do here is get an understanding of what we are being told by manufacturers, not contradict what other users are saying.

I am currently running my caravan on a second hand AGM battery that came from a mobility scooter. It was over 1 year old when I got it yet for a 100ah battery it tested, using my "destructive" tester at 98 ah. At the end of this season I will test it again and report my findings. For now though I cannot see how any expensive semi traction battery can last longer or give more energy than a cheap car starter battery.

[Rayjsj]

Derek Uzzell - 2016-09-21 7:46 AM

 

Just in case it proves significant, it might also be worth confirming the Banner battery’s date of manufacture.

 

An “Energy Bull” battery carries a 5-letter group (eg. CFBDF) next to its negative terminal.

 

The week/year date of manufacture is identified by the initial 4 letters of that group, with A=0, B=1, C=2 etc. The 1st pair of letters identifies the week and the 2nd pair of letters identifies the year.

 

So CFBD would equate to 2513 and indicate that the battery had been made in the 25th week of 2013.

 

(Apparently the 5th letter in the group provides Banner with information identifying the person in charge of the production line.)

 

There is another 5-character group next to the battery’s positive terminal and this identifies the production line and battery make-up.

 

Thanks for this valuable information Derek, very helpful.

By the way, my failed Banner battery is being replaced FOC, by Alpha batteries , it arrives tomorrow.

I bought it online back in Oct.2014 , luckily by pay pal, so i was able to e-mail them the sales invoice and invoice number ,So, was able to claim on the 4 year warranty.

They didnt want the old battery back for testing ? Which i find a bit odd. Perhaps a bad batch ?

[mrbigfeet]

Hey Rayjsj, what made Alpha consider it had failed under warranty? My supplier says mine has not failed.

[Rayjsj]

mrbigfeet - 2016-09-30 2:51 PM

 

Hey Rayjsj, what made Alpha consider it had failed under warranty? My supplier says mine has not failed.

 

The battery got red hot, gassed off nearly all of its fluid, even though fluid levels were checked regularly (although battery is sold as being maintenance free...it is not !) Then when topped up and reconnected got hot and gassing off again, not the charger, as 2nd battery also a Banner, is still fine, although it too needed topping up.

Battery doesnt now hold a charge.

Sent them an e-mail with all the information, they sent a new one, under warranty. As they should, they are not cheap batteries !

[aandncaravan]

mrbigfeet - 2016-09-29 8:47 PM

 

My battery date code give week 39 2013 and I bought it in Jan 2014.

I think Tracker nailed it when he said " inadequate handbook instructions to owners". Judging by the different responses to this and other threads on the subject, people have very different views on looking after lead acid batteries. Aandncaravan provided a couple of interesting graphs to support his view. However, what comprises a "Cycle"? I know it means charges but how do you determine when a charge wont happen and what happens to the battery capacity in the mean time? Also, the State Of Charge voltages show 12.1 volts for 50% charged. I have beet told that Banner batteries are 50% at 12.5 volts but I see Banner quote 12.2 volts for a Conventional Battery (vented).

I can see that a Watt Meter can display power in and power out of a battery and that works well when you don't have solar or mains charging connected. But with a charger connected in use, I fail to understand how it can tell you the "condition" of a battery.

Batteries are sold as being able to supply, in the case of a 115ah battery, 5.75 amps for 20 hours. Banner quote this in their technical blurb, see below under Capacity.

http://issuu.com/bannerbatterien/docs/technischerratgebergb12.2014/71?e=0

My method of testing may well be a destructive one but how else is one to properly test a battery? By destructive it surely means "reduces charge cycles" as opposed to "destroys battery immediately"

Another puzzle. If Banner talk of supplying energy down to 10.5 volts, why do Exide talk of 0% charge below 11.8 volts? (see above graphs).

All I'm trying to do here is get an understanding of what we are being told by manufacturers, not contradict what other users are saying.

I am currently running my caravan on a second hand AGM battery that came from a mobility scooter. It was over 1 year old when I got it yet for a 100ah battery it tested, using my "destructive" tester at 98 ah. At the end of this season I will test it again and report my findings. For now though I cannot see how any expensive semi traction battery can last longer or give more energy than a cheap car starter battery.

 

 

 

Just because manufacturers documentation quotes that a '115ah battery, can supply 5.75 amps for 20 hours' it doesn't mean it is a good idea to let it.

There is usually other advice supplied in their other documents that then tells you how to best care for the battery, usually with advice not to drop it below 50%, ideally only 30% if you want maximum life.

 

I am 100% sure that the Banner documentation is correct, the 115Ah battery WILL supply '5.75 amps for 20 hours', but don't expect it to do so more than once!!

The 'Multifit' Graph I posted above shows reduced cycles the greater it is discharged, by if you follow all three battery graphs back to 100% discharge you will also see it results in a single cycle.

 

What a battery CAN do and what you should ask it to do in realistic use is not the same at all.

You might argue that is misleading, and we would agree.

 

You write :

"I can see that a Watt Meter can display power in and power out of a battery .... But I fail to understand how it can tell you the "condition" of a battery".

 

It is one of the best guides to battery ability. Most batteries lose a small amount of capacity each time they are discharged then charged, there are several factors involved in this. They are not 100% efficient until they suddenly die as some seem to think.

In fact even a brand new unused battery is unlikely to be 100% efficient, it will probably needed 107Ah to charge it up.

 

Lets assume we have a magical 100Ah battery that, for arguments sake, we are able to draw out 100Ah of energy.

To charge this '100Ah' battery when new takes 107Ah.

After being charged and discharged 30 times you might need to put in 112Ah but only get out 96Ah.

After 200 'uses' it might need 130Ah to charge it fully but only give out 79Ah, that is 51Ah lost.

You can see that if we are now recording how much power goes in and what we take out, it will give us a good idea of it's efficiency?

 

Now this doesn't mean such a battery is about to die, even an 'inefficient' battery might be holding good charge and appearing to behave acceptably.

But in terms of a battery charged by a Solar Panel it is a disaster. My 'imaginary' Solar panels 35Ah a

day might be enough to fully charge a battery after a nights use when the battery is new, but wasting 51Ah (more than an entire days potential Solar charge) is not good.

 

 

You can see that each subsequent cycle will be shorter (in delivering usable power) than the one before.

So by the time a battery is 3 years old that 'cycle' might be delivering just 30Ah. Yet for most manufacturers it still counts as a Cycle.

By 4 years it might be just 20Ah for a 140Ah charge and you probably start to notice!!. But that still might be counted as a 'Cycle' by some manufacturers even though it is of little real value.

 

So in answer to your question on what is a 'Cycle', make up your own mind, I have never found a good definition that they all adhere to.

Some manufacturers only count what they see as 'useful' cycles, others every one, even when of little value.

We suspect a Yuasa battery that quotes only 200 cycles might deliver far more real world power than a '400 cycle' Lion, for example.

 

 

The above figures are for demonstration of what can happen, they are not real figures. However, a Wattmeter WILL give you real figures.

 

A budget battery at 2 years old could be down to 60% efficiency but still be giving 'good service' in the eyes of it's owner. He just doesn't realise how poor it has become.

When someone tells you their battery is 6 years old and 'still going strong', you can bet they don't have a Watt Metter to tell the real story? Batteries deteriorate with use, that is how the chemistry works.

If it is 6 years old and been used regularly, Physics says it can't be a 'good' battery,

 

You write :

"For now though I cannot see how any expensive semi traction battery can last longer or give more energy than a cheap car starter battery".

 

Because not all Wet/Flooded Lead batteries are made the same way.

The Varta LFD/Bosch L5 range as so special because it maintains efficiency right to end of life, up to 70% more electrical conductivity than a normal battery of the same age. It will still slowly degrade, but much less than other technologies.

 

It uses a high Silver Alloy for the Grid which is not Stamped or Pressed in the usual way, but 'Rolled'. This gives the Grid a molecular structure which is highly resistant to the corrosion that blights all other Lead Acid batteries, including AGM and Gel. It is a patented process, called Powerframe. No one can copy it without license.

 

The process stops corrosion that would otherwise cause a resistance to electrical flow, both into and out of the battery. Bosch quote 70% improved electrical flow.

This means the battery charges faster, gives up it's stored energy without reduced 'electrical loss', needs less Ah to charge up, is able to handle higher current discharges, handles higher temperatures better, etc.

 

In a normal battery (including AGM and Gel which still suffer Grid corrosion) the corrosion builds up on the Grid tending to not only impede electrical flow, but also dislodge the Paste from the Plate.

So a Powerframe battery lasts much longer, giving much more of it's power right to end of life.

 

So not all Wet batteries are the same, not by any means. New technologies are evolving all the time.

 

 

Why did A and N Caravan get into batteries in such a big way?

Because they are the biggest cause of failure of the Motorhome chargers we repair. You can see from the example above, that a budget battery two years old might need 140Ah to charge it up but only gives back 55Ah (wasting 85Ah) is going to place a much greater load on any MH charging system (Alternator, Mains, generator or Solar) than a Powerframe battery. Not because each charge and discharge is a greater load in itself, but the charger will have to go through almost 2 charging cycles versus an LFD to deliver the same 100Ah. That is a load on the charger nearly 4 times a Varta LFD in real terms for each 100Ah drawn out of the battery.

How long do you need to drive on Alternator for that? 6 hours versus 2 hour driving?

 

Once again figures exaggerated to show the trend, but if Bosch/Varta claim 70% better efficiency for the LFD we are not talking small figures.

 

 

See the photo below of a typical aged battery on the left and Powerframe battery of the same age on the right. It doesn't take a genius to work out that the Grid growth/corrosion on the left is going to stop the energy in the battery getting out, as well as providing a resistance to the charge going in.

An ordinary battery will corrode faster if the power charge/discharge is higher than ideal, or if the temperatures are elevated, etc. A Bosch L5, Varta LFD90 is pretty much immune to all these.

Oh, yes, it is also cheaper to produce, 20% lower production energy costs, so you save there as well.

 

It really is an amazing battery for the money.

 

 

 

[mrbigfeet]

Wow Rayjsj, that really is some fault. Not what you would expect from an expensive battery.

Many thanks Aandncaravan for your information. I wish I had known about the Powerframe battery sooner; I would DEFINITELY NOT have bought a Banner battery! I will not be buying another and would advise others to consider the Powerframe first.

Caravan and motor-home batteries seem to be yet another product where the manufacturers can make unproveable claims about their products. My expectations are that if I pay more money for more capacity then that is what I get. I don't expect that when the product fails to meet the manufacturers claims that I will be told that I must have used it wrong without being told how to use it right! It is all very well saying not to take it below a certain capacity but when you are not connected to a mains supply, how do you do that? A solar panel seemed to be the answer but unfortunately for me that did not work. I wonder how many other campers have been told that it is the way they use their battery that caused its failure? I wonder if any other camper has found a working solution???