batteries and soalr panels

Submitted: Wednesday, Feb 21, 2007 at 20:47
ThreadID: 123353 Views:4191 Replies:4 FollowUps:7
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Our van is still on the production list with a few months left to wait.
At this stage we have requested three solar panels and three batteries. However after doing more power usage calculations we feel sure that we need a fourth panel. The question is do we stay with three batteries with the aim to keep them fully charged or add the extra batttery in the hope that they will maintain max charge anyway? We know that not getting battereis to the full charge regularly will reduce their life. We prefer to spend as little time as possible in powered camp sites. We have an aux battery in our tow vehicle, a 64 watt portable solar panel and a Honda 2KV generator (but spend a lot of time in National Parks). We are keen to know the experience of 4 x 4 and 4 x 3 users. Any advise would be welcome.
question 2: Pros and cons on Bargman handle/light or grab rail at door.
thanks Graham

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Reply By: Pixellator - Wednesday, Feb 21, 2007 at 21:04

Wednesday, Feb 21, 2007 at 21:04
Hi Graham and Barbara

We have 4x solar panels and 4x AGM batteries in our almost two year old BT.
Despite all the accolades given about the longevity and indestructibility of the batteries, we were disappointed to have to replace our four batteries this month. Only a small proportion of our eighteen months 'on the road' all over Australia has been spent off 240 power, so, on a dollar per 'free' camp basis, it has been an expensive experience. However we remain philosophical about our experience. We have received excellent assistance and advice from all at Bushtracker, as well as Keith from OmegaLec, the manufacturer of the solar regulator.
My advice would be to have a good discussion with Steve, or John at Bushtracker about the most successful way of looking after your power system... their help is invaluable and always available.

Regarding the Bargeman, we have one on our van, but only rarely use it. We have a grab rail fitted on the inside timber panel as you enter the van... for us it is a much better aid to entry. The light on the Bargeman is a 12v incandescent, so you'd probably tend not to use it much when you're on battery power. The normal under awning light gives superior illumination. I believe the present light being used is either fluoro or LED. On that issue, if I was re-designing,I would place exterior lights on all four sides of the van, or at least on the driver's side.

Just my opinions after two years' BT experience...
AnswerID: 570689

Follow Up By:- Wednesday, Feb 21, 2007 at 21:16

Wednesday, Feb 21, 2007 at 21:16
Hi Bob,

Just getting edumecated myself, when you say 4 panels and 4 batteries what is that in watts for the panels and amps for the batteries? And what was the problem in the end?

Kind regards

FollowupID: 847268

Reply By: Tassie Bushies - Thursday, Feb 22, 2007 at 08:55

Thursday, Feb 22, 2007 at 08:55
Hi Graham & Barbara.
Well 4 & 4 is the way to go I believe. This yr spent 2.5 Months in Qld. bush & only turned geni. on once. Didn't really have to, just a top up, & to test new geni. a bit.
3 & 3 use gennies much more, can't help with 4 & 3 (ASK STEVE) he will tell you true.
Bargeman Yes( usually only turn on light when getting back to the van, helps find the key hole 2) + Grab rail inside, they cost little for the security of not falling out the door.
Regards Peter.

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AnswerID: 570690

Reply By: Bushtracker - Thursday, Feb 22, 2007 at 20:10

Thursday, Feb 22, 2007 at 20:10
Graham and Barbara,

lone Ranger here, with the advantage of the oversight of how the 1000 are going:

First of all on the issue of solar matched to batteries, what works the best in real life is about a one to one ratio of 130 watt panel to 100 Amp Hour batteries Four panels matched to three batteries, wastes solar in good weather as the system shuts down mid day with batteries fully charged and no where for the solar to go... And the converse is the opposite problem, three panels with four batteries, and you have the opposite effect, where the solar is always struggling to bring up the batteries and the lack of a full charge on the batteries abuses them and shortens their life.... And I would recommend the 100 Amp Hour AGM x Hybrid German A-200 Gel batteries, they have proven very robust…

Now, the best way to MAXIMISE battery life, is to understand how they work in practice and what shortens their lives... Here is some reading for you..

And this is a little dated, but still relatively on track:

Do you wonder why some people talk about their batteries lasting many years, and then you hear of someone else that has actually killed batteries in a very short time??? It is most often not the batteries fault… While there have been rare occasions of defective batteries, they are only in about 1 in 200, to about 1 in 500 in actual occurrence. The premature death of batteries in practice is cause by abuse, neglect, or just plain working them too hard… I have been ask to put some guidelines on battery use on the BOG site, so here goes… If a battery has a design life of say 1000 Cycles (discharge and full recharge), if the battery is cycled less than the full cycle discharge, you might get 2000 cycles. If the battery is run down too far before being recharged, you might only get 500 cycles out of it… Understand? Now if you do not charge it properly or enough, if you run it down way to far, if you do not charge it up all the way, or if you leave it in a discharged state too long, you can get even less than 500 cycles or KILL THE BATTERIES ALTOGETHER!!! Abuse of batteries is like running cheap or wrong oil in your engine, you greatly would shorten the life in your car… Try running water in your engine until it dies…That is like running a battery clear down to about 10 volts on your satellite dish or stereo amplifier, or auxiliary freezer in the truck, and then thinking “Oh well I will charge it up good in a few days when I get to Woop Woop….” That is like topping off the oil in your Landcruiser with turpentine or something… A good way to ruin both!!! Be careful… I still have the first three AGM batteries running in my truck after years of work, with a 100 ltr fridge freezer running non stop, lights in the horse truck, and a 12v power winch running the 12’ ramp up and down…. But I am running those batteries within the guidelines of proper cycles without abusing them….!!!

A battery like the AGM with A-200 Gel, or a standard AGM, or straight Gel Cell, should be treated with care. When it gets down to 12 volts it is about 50% depleted. The less time you run it below 12 volts, the longer it will last. If you routinely charged it up from 12 volts, you might get twice the design life out of it. Now, yes it is important to exercise it and stretch that cycle down further, but that will happen naturally in bad weather off Solar, when you run it down to 11.5 or even 11 volts every couple of weeks or so…. But if you completely flatten it all the way down to 10.5-11 volts all the time, you are shortening it’s life. It is nice to have all the toys, flat screen TV’s, stereo amplifiers running outside speakers, extra fridges in the tow vehicle, microwaves, and all the rest of the creature comforts like Satellite dishes and Satellite decoders… But there is a cost to that in $, and the weak link is battery care. If you find you are going below 12v, below 11.5 all the time…. You will either invest in more solar and run more batteries, or you have to accept the fact that you will be replacing batteries on a regular basis…. Cheap batteries are not the answer, they just waste solar input with thicker plates that require more energy to excite them, require water adding maintenance, make more explosive fumes, and corrode terminals and cable, and just require a lot more maintenance. The answer is better care of the good batteries…

A lot of the current battery problems of late, are with people unknowingly misusing their 12 volt systems. When someone has crashed all three of their batteries, while we are getting it handled on a warrantee basis most of the time, the truth is that the people do not have three defective batteries, they have unintentionally ruined their batteries by running them down too low or leaving them down low for too long. Some examples of this unknowing abuse of their battery systems are like the following:

1) They are running the batteries too low with their inverters, when they really cannot afford or don't have the excess power... Some inverter choices did not have a built in Low Voltage Disconnect until the last couple years... People need to live within their power limits, and not use power hungry luxury items when the weather is off or their batteries are not full up…. Flat screen TV’s, stereos systems, satellite dishes and decoders, microwaves, and other luxury items need to be used sparingly when the batteries are not up in the upper range of being fully charged. We state that 3 –120 watt panels and 3 batteries hits the 90% of Customer satisfaction, but then many are adding more stereo, TV, satellite dish, type systems after that, when they really should go too 4 panels and 4 batteries if they are going to do that…

2) Some people are continuing to run accessories when the batteries are too low without their knowledge, fridges in tow vehicles and the like. As I have said, People are unintentionally ruining good batteries through over use-abuse running them down too low and or leaving them there too long... We have tried to build in the LVD, (Low Voltage Disconnect) to cover this, but the Anderson Plugs bypass the system and allows unintentional abuse, running them down with luxury items in the tow vehicles, stereos left on, extra fridges, and the like in the tow vehicle that is running through the Anderson Plug bypassing the LVD protection in the caravan itself and running off the batteries directly. The Anderson Plug extra connection, should be reserved for people that actually have surplus solar power, which is what it was designed for, like 4- 120 watt panels and 4 batteries. Then it makes sense.

3) Some people are even actually overcharging their batteries, with large cable running to Anderson Plugs, allowing the alternators to pump up the batteries too high when on long driving trips. The sealed batteries don't like voltages over about 14.4v for very long, and we have seen alternators on tow vehicles putting out up to 15 volts and hold them there for as long as the engine is running. This hurts the batteries over time, depleting the electrolyte. This is another case of unintentional abuse of the batteries.. And why we do not like to put in the larger battery cable size of wire back to the 20amp Anderson Plugs. If we restrict the wire size to 6mm, yes we do get about a half volt loss, but that suits the batteries better as we have seen tow vehicles put out 14.9-15 volts and the Gel, Hybrid, and AGM batteries are restricted to 14.4-14.5. This can be overcome with a large Diode, which will drop the voltage a half volt, but this will restrict the Anderson plug to charging only, not drawing power back, as the Diode blocks it in that direction… There in is its own problem, more in another section on “Anderson Plugs”..

4) Some people are actually adding more toys on board later; some have even directly connected to the battery system, allowing them to use power and run the batteries lower than they are designed for.... After having abused or killed their batteries, they are often “in denial” as many do not understand how the electrical system works, and we cannot entirely stop them from unintentionally abusing it...

And then, all of this ends up our fault of course... There is no easy way to handle this... Some people are just using too much power with elaborate stereo and TV and satellite systems, and other accessories like Satellite Decoders and extra fridges, and the like... For instance one person, came in with an
unaccountable power draw draining their batteries overnight, that was chased down to a Satellite Decoder that was drawing 3 amps 24 hours a day in power even when not in use!!! Ouch!!... It is very hard for us to regulate how much power people are able to use, and about one in twenty of our Bushtracker Owners just do not understand or pay attention to the power available, as they are unintentionally abusing their battery systems one way or another. It is an ongoing challenge for us...

One way we have tried to overcome this is to try and educate the Owners on how to live with 12volt storage battery systems, so we are ever increasing the size of the Owners Manual with added information… Well and good, but some people do not read the Owners Manual… . It is almost a joke about men, that they do not read the Owners Manual until they have broken something. We strongly recommend that our Owners Manual is read to prevent damage.

Another way we have tried to overcome this is to continue to evolve automated LVD and HVD systems. For instance, we now have an LVD (Low Voltage Disconnect) that we can put in the Anderson Plug line. If people leave a stereo on, a fridge running, something that is a current draw through the Anderson Plug, we have a neat LVD device that will automatically cut out the circuit and only put it back in when the voltage rises to a preset level in the batteries… Good idea, but it costs around $400, so the protective cure is more costly than the occasional case of people ruining their batteries.

Another and the best way may be by building a stronger battery that is better able to survive the abuse.... This has been what we have tried to do. We have the first 500 in the country. They are the 100 Amp Hour Hybrid AGM (Absorbed Glass Matt) battery with German A-200 Gel. We have severely tested them with huge cycles, and even left them down in a badly discharged state, abusing them for days as a severe test only. While we do not encourage or advise such extreme abuse, we have tested them to that level ourselves in our own Quality Control research. We are not saying that they cannot be ruined, but they survived some rigorous testing that would have ruined other batteries… But you need to understand that you still can kill them, and the better the care, the longer they last…

We are always trying to build better systems and equipment to keep the Clients from unintentionally ruining their equipment. Part of that care are things in place now, like LVD disconnects we have had built into the inverters, and LVD and Audible Alarms in the new 40 amp Regulators…. But we cannot completely make it foolproof… In the end, there is only so much the “Lone Ranger” can do without your help… That is where you come in…

Also see TIP # 78 Maintenance on Maintenance Free Batteries,
TIP # 83 On Discovered Battery Maintenance Problem
TIP # 95 On Battery Cycles in Storage
And TIPs # 133 adn 133 (A) On Code Secrets to the Talking Battery Charger...

Take care… and Kind Regards

AnswerID: 570691

Follow Up By: gottabjoaken - Wednesday, Feb 28, 2007 at 23:50

Wednesday, Feb 28, 2007 at 23:50

with talk of three or four batteries, what is your opinion on using larger batteries ao as to reduce the number of cells, considering the suggestion that any one cell failing can damage the whole bank, so fewer cells the better ?

ie 2 x 200AHr rather than 4 x 100 AHr

FollowupID: 847269

Follow Up By: Bushtracker - Thursday, Mar 01, 2007 at 18:41

Thursday, Mar 01, 2007 at 18:41
Hello gottabejoaken Ken,
What you say makes sense from your perspective.... It only stops making sense when you put it into practice like I have done living with Marine 200 AH batteries since about 1979..

Let me explain why, a couple of things you could not be expected to know, or might have not considered...

1) 200 AH batteries weigh 150 pounds each. If you ever tried to muscle one around in tight corners you would soon learn to absolute HATE messing with them. They would be a leading cause of back injuries here, and anywhere that had to service them...

2) Also: Most of the 200 AH batteries are MADE with one cell a bit weaker than the rest... Now this is an OUTRAGEOUS CLAIM, that the Manufacturers would deny.... But I used to have a Company that equipped major world cruising yachts, and we would see it time and time again. The cell failure would drag down the battery, and it would not be in the location that you would assume it to be, it was in a location that seemed to be just a bit light on manufacture, and the batteries would make an early death drug down by the weak cell at about 2 years life... It was if they were designed to do so with "Planned Obsolescence"... It proved to be better to have them broken up into smaller blocks, and while you could still get a weak battery, you could replace one if you caught it in time and nurse the rest of the set for an additional year or two in severe duty.. The 200 AH size in big earth moving equipment are sometimes just given the heave on this timetable because of the long term experience, same as on some larger yachts..

3) Possibly due to heat dissapation and other factors, this overall concept is why the best size has proven to be about the 100 AH... Even when I did a re-industrialization project of 18 acres of Labs and such over 18 months with a 15 man Crew, our work vehicles were Golf cart style vehicles running on deep cycle batteries charged overnight...For the air quality. Any way, this is the Extreme of deep cycle discharge and recharge everyday that KILLS batteries. And of all the battery styles and combinations we tried, the smaller size held up better...

Any way, nice try, you are thinking.... But no, we will never go larger for the reasons above...

Regards from the Ranger...

FollowupID: 847270

Follow Up By: gottabjoaken - Thursday, Mar 01, 2007 at 22:19

Thursday, Mar 01, 2007 at 22:19
Thanks, Steve.

that does make sense.

How do I recognise that a cell is failing under normal usage conditions and monitoring?

FollowupID: 847271

Follow Up By: Bushtracker - Thursday, Mar 01, 2007 at 22:39

Thursday, Mar 01, 2007 at 22:39
You would only do the following if you thought you had a problem, as in your batteries not taking a charge well, or not holding a charge well, discharging prematurely overnight to a LVD Low voltage disconnect or something suspect... And it could also be a terminal loose or a broken cable...

Even if they were not bad, it would not hurt to run this test when you access them now and then to look for things like a terminal loose or broken cable..... To test them, once or twice a year you could check cables and terminals and do the following to see if you had a weak one in the batch:

Get as much charge as you can into them as a group, and then disconnect them all from the charge as in solar and charger off, and no load and then disconnect them from each other... If there are no mechanical problems in connection: One with a bad cell or crashed plates or something internally broken, will show up as a lower voltage battery from right away to a couple of hours depending on what the problem is.... The longer you leave it disconnected from the others as in hours, the lower it will go.... But if it is a serious problem, you should see it obviously, in an hour or two. The good batteries will come down from their equalizing finish voltage of 14-14.4 , down to stabilize at rest at 12.8-13 volts with no load, and the bad one will be much lower and continue to go down. It should be obvious with a voltmeter, if you have a bad one. A tenth or two tenths of a volt difference between the batteries is nothing to worry about. A bad one will show a big drop depending on the problem..

To confirm a bad battery, charge it alone and repeat the test. It could just have been a wiring problem and it was not getting a full charge in the first place. But if you test the bad one alone, and disconnected it fall off the edge again, you know it is st****ed.

Another example of a bad battery in a test is that if it comes up to high voltage right away under a charge, but under a load it drops dramatically right away, again it is ready for the scrap heap... It is only showing an immediate surface voltage on the plates but not accepting a proper charge, so when you put a load on it, it falls off immediately.

A marginal one might be resurrected with a big charge overnight, if the problem was a bad connection in the battery group so it was not getting a full charge in the first place... A big overnight blast might save it, burning through resistance, and it could come back online... But anyway, this is the few most common conditions to look for... OK?

Regards, Ranger

FollowupID: 847272

Follow Up By: gottabjoaken - Thursday, Mar 01, 2007 at 22:47

Thursday, Mar 01, 2007 at 22:47
thanks a heap, Steve.

very useful.

FollowupID: 847273

Reply By: Graham & Barbara - Wednesday, Feb 28, 2007 at 20:41

Wednesday, Feb 28, 2007 at 20:41
Thanks for the information. we have now decided to go four solar panels and four batteries. regards Graham
AnswerID: 570692

Follow Up By: Bushtracker - Thursday, Mar 01, 2007 at 18:48

Thursday, Mar 01, 2007 at 18:48
Graham and Barbara,
And Newbies in planning,

The 4 plus 4 level is what we recommend if someone is planning flat screen TVs or Satellite hook ups, that kind of thing pushes the borderline of what you can live with in the 3 plus 3...

That or an extension lead to power an additional fridge in the tow vehicle, medical breathing gear at night; anything like that is outside the normal van requirements pushes the need to go up to the 4 plus 4 level...

Luxury in the Bush, is measured in power and water. You never have too much, and the more you have the more luxurious you can live. Just the way it is. I personally have 4 plus 4, and 8 water tanks. Of course I do not run around with all 8 full, but as they are all plumbed separately I can select to fill them all at the last Outpost of Civilized water supply. They weigh nothing when empty, but Lifestyle is all about power and water and it sure is nice to ample supply of each. Our mainstream happy Client travels with 4 or 5, some try to get away with 3, but I travel with 8.

Regards, Ranger
FollowupID: 847274

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