PDA

View Full Version : best value for money battery for camping?



ozzyboy
3rd July 2013, 01:59 PM
I have an ark battery box for the camper trailer. Did have a 100 amp battery however this got so low on charge, I couldn't recharge it.

While out camping, I run a 80 litre waeco, led lighting and battery chargers.

Any thoughts on what is a good priced battery, that will do what I need, usually 3 days at a time??

cheers

ozz

Cuppa
3rd July 2013, 02:46 PM
Despite what some folk claim, running an 80 litre Waeco off a 100h battery for three days just isn't going to cut the mustard & the result will be that you murder your battery (of any brand) prematurely.

That said it is possible that your attempts at murder have not yet been completely successful & that you could potentially resurrect the one you have already have. I have had an AGM battery which my smart charger simply refused to charge, basically giving me an error code indicating the battery was dead & gone to heaven. However after putting said battery on a small, non-intelligent trickle charger (an ancient motorcycle battery charger) & leaving it overnight I managed to get sufficient charge into it, so that the next day when I put it back onto the smart charger, it was back in favour, & able to be fully charged. That was several months ago, & the battery (used for standby lighting during power failures) is still holding it charge well.

If you want your battery to last, & to get value for money from it you really have to treat it more kindly. This means not discharging it below 50% of it's capacity. In other words with a 100ah battery you have only 50ah of useable capacity. This is close to, or below what an 80 litre Waeco will use in a 24 hour period. With no other input (solar, alternator or gennie) whilst you could possibly be able to just about keep the Waeco going for 3 days (although I'd doubt 72 hours) doing so will, as you've likely discovered, kill the battery. You could probably get away with it a few times before the battery karks it, but I doubt you'd get more than a year, if that, out of a battery used that way. Keep the battery above that 50% mark & you can get MUCH longer. I have some AGM's that are now over 8 years old & still going strong, & hope to get another couple of years out of them. Their voltage has never been below 12.3v. Of course this means having greater battery capacity (& weight) to get you through the 3 days.
If getting at least 200ah & preferably 300ah is not feasible then my advice would be to continue doing what you are doing, but buy the cheapest batteries you can find. Paying more for good batteries that then essentially get severely abused is just wasting good money 'cos you'll kill'em anyway.


Cuppa

Ps. Even if buying 200ah, I'd still go for cheapies & accept that they would only get a limited life. 300ah & buying better quality starts to make sense.

threedogs
3rd July 2013, 02:52 PM
Look at the Trojan range in wet cell and also look at an 80watt solar panel
to help your battery out a bit more. Wet cell give more bang per buck but be aware of fumes etc in confined spaces.
Not sure on your set up but we [mates] take an ice box for drinks and use the Engel for food ,milk etc.
That way its not being opened all the time, works great leaving plenty of 12v for camp lighting

Cuppa
3rd July 2013, 03:37 PM
Sorry TD, but as usual I find myself in disagreement with you about batteries (& solar)

Trojan wets are excellent quality batteries, but as you say fumes can be an issue if being charged inside the vehicle. They are 'old school'. If they are being properly charged, they will gas & this is not only potentially dangerous in the confined interior of the car, but also very unpleasant. If they don't gas they are not being fully charged, meaning that you have even less useable capacity. Whilst as I said, I agree that Trojan wets are good quality batteries I would still advocate for cheapies unless setting up with a GOOD (read well balanced) charging system.
Wet batteries, when charged to their full capacity (unlike crank batteries) also need regular topping up maintenance. Again if they don't need topping up they are not being properly charged.

I had some wet deep cycle batteries inside a vehicle once, they didn't stay there long , & I would NEVER advise anyone else to do so from both a safety perspective & just because they stink. However if they are not being charged in the car that is a different matter, but still leaves the issue of possibly paying for quality that won't ever see it's lifetime potential.

Actually I think there is little reason to buy wet deep cycle batteries these days, unless keeping costs down for a large battery bank are are the aim, & that's not going to be an issue in a 4wd.

Also don,t buy Calcium or gel types, they can be really finicky, & many chargers & alternators are not set up to charge Calcium batteries properly.

Best are AGM,s (absorbed glass mat - similar but not the same as gel, although they are often incorrectly referred to as gel).
They don't gas (unless there is a serious overcharging problem when a pressure relief valve lets go), can be placed in any orientation (easier to fit) & charge more quickly than wet batteries (important if relying on alternator charging whilst driving or limited hours of sunshine with solar). Also no concerns about acid spillage.
There are different types of AGM's, intended for different uses. For mobile use in vehicles that see corrugations etc the DC series are generally considered the best option (not to be confused with DC - direct current which all the batteries produce).
Other types are better, for example, for uninterruptible power supplies, golf buggies & scooters etc. generally these types will not stand up to vehicular vibration for as long as the DC series batteries.

AGM,s have been around for a couple of decades now, & are well proven. The new generation of batteries that are now starting to see more widespread usage in the RV scene are the Lithiums. Not the same as those that power our cordless drills etc, but LiFeP04. These are being developed primarily for powering electric vehicles, but have started being used as 'house batteries in RV. They are still in the early stages of development, & whilst a number of folk are swearing by them, they are not yet at the stage where they are fit & forget, requiring a degree of uderstanding & monitoring by their owners. They have a few significant advantages over previous battery types, the main one of interest to us is that they are about half the weight of AGM's, & discharging them completely does them no harm. Kimberley Kampers already offer them as an (expensive option) & just in the past few days I have read of a new 'complete system' available on the market. It is 400ah (essentially equivalent to 800ah of AGM, the weight of 200ah AGM, at a cost of $7,500. Still out of reach of most folk, but in a few years time when prices have come down, & the control systems built on a mass scale, these are most likely what we'll all be fitting.

Cuppa



Cuppa

muletopia
5th July 2013, 10:18 PM
I read Cuppa's comments on LiFeP04 batteries with interest, Googling " Technomad" or searching for 12 deep cycle Lithium ion batteries leads to technomad. These people agree that the technology is currently bleeding edge and expensive. Thay point out that in addition to the advantages Cuppa mentions that these batteries are also good for pehaps twice the number of charge/discharge cycles than lead acid batteries such that the price/discharge cyle is actually less for the Li ion batteries. So if the price of these batteries and controlers comes down and you only want a week off power does it become cheaper/more convenient to fit a large Li ion battery set and not bother with solar power? It would seem to be lighter, simpler and easier to install than a PV system. Then sunlight/shade is not a problem and the fragile external panels are removed.
Muletopia

Cuppa
5th July 2013, 10:53 PM
I think that's the way it's headed Muletopia.
However LiFeP04 (Lithium Iron Phosphate) are not the same as Lithium ion. Li ion are the type use in many cordless tools. There are a number of different types of 'Lithium' batteries, & other forums have seen lots of heated debates about their merits, often with those arguing talking about different types of 'Lithium'.

I have asked a friend who has 2 or 3 years experience setting up LiFePo4 systems for himself & others what the current cost to set up as you suggest might be, utilising already owned battery charger at home. Will feed back when I learn more.

Cuppa

Cuppa
6th July 2013, 01:29 PM
The good info on what is required to run an 80 litre fridge for 72 hours is a battery or batteries with a useable capacity of around 200ah. This is based on an average current draw as stated by Waeco for their 80 litre fridge of 2.9amps at an ambient temperature of 32 degrees.C. It also takes into account that the fridge probably won't be needed for the full 72 hours (ie. during the drive back home). A single 100w or 120w solar panel would extend the 72 hours significantly.

Note the word useable. With lead acid batteries (wet, AGM, gel) this means that 400ah batteries are required. Cost for these would be around $1200 to $1400. Weight would be around 120kg.

In comparison to get a useable 200ah with LiFePo4 you would need a battery pack with a capacity of 200ah, which would also cost around $1200, but would only weigh less than 40kg & take up less than half the space of of their Lead acid equivalents.
In addition they have a much longer life. If the battery were discharged 100% on each occasion it were used, it would give 1000 x 3 day weekends. If discharges were less life would be even longer. So long term cost is much less.

The price to pay for this cutting edge technology if unwilling to pay the huge markups the few companies who are are marketing 'all up systems', & instead going DIY is a need to understand a new technology. I'm not there yet, but it seems there actually isn't that much to understand, just a couple of new (to me at least) words. These centre around the charging requirements of LiFePo4. Basically they charge far more quickly than lead acid, & can take pretty much however many amps you can throw at them. A battery pack is made up of several 'cells' strapped together, & it is important to ensure that when charging that none of the cells rises above a certain voltage & gets out of balance with the rest. This is achieved by using a doohickey called a 'cell logger' which monitors the voltage of each cell, & cuts off the charge if voltage difference between cells rises beyond a preset amount. In practice after an initial 'balancing, it is very rare for cells to get out of balance. The folks I know who use them have all been using them for up to a couple of years now, & not found this to be an issue. The companies who sell the expensive 'all in' systems use the same batteries, but charge an arm & a leg for their 'battery management systems'. For the Diy'er, folks I know have proven, in multiple systems, & in full time use over a couple of years that these battery management systems can be put together quite easily & at little cost ..... Less than $75. Those selling proprietary battery management systems have a vested interest in persisting with stories of batteries exploding, paranoia is good for their business. I know of at least 50 folk now using DIY battery management on LiFePo4 without problem. The rare problem of batteries catching fire have been in electric vehicles where there are quite different parameters used compared to RV use.

The details of the BMS, both DIY & proprietary are still guarded closely, but if anyone is genuinely interested in Diy LiFePo4 I can put you in touch with someone.

http://www.evworks.com.au/index.php?product=BAT-LFP200AHA

200ah would be 4 of those cells strapped together.

Just to be clear, I am no expert on this stuff & have no direct experience of LiFePo4 myself, just passing on the bits & pieces I know. However if I were starting the fit out of my Patrol camper now, there is no doubt that I would use the LiFePo4’s in place of the 105kgs of AGM batteries I have (3 x 120ah).

Cuppa

threedogs
6th July 2013, 01:44 PM
Think we are a bit limited by the size of batteries required , need to learn how to use what power we have in a smarter way.
LEDs for lighting helps heaps. 300 lumens is a ball park figure for Camp lighting, My campsites look like the Queen Mary docked
sometimes and using minimum power, I have all my/other drinks on ice. Usually as night rolls on I disconnect lights,
My MP3 plays background tunes during the day no doof doof., I have a special light and bracket to look over the campfire cooking.
and another dedicated light over my prep bench, all led strip. powered from an 18 ah motor bike size deep cycle. I worked on 9 hrs a night usage
which I'll never use unless I forget to unplug it. might have to put them on a timer LOL, Lights on say 6.00pm in winter and off at 1.00am So using 5 hrs
You get the picture. Plus I use a box similar to your ARK that if need be I can take down to the river with a light pole and light and stay there fishing for a while.
Still have my 105 AH Trojan with water kit in the GU for Engel duties and awning led strip light, and another 100 ah seal in my camper for anything I like. And all backed up
with an 80 watt solar panel if needed

P4trol
6th July 2013, 02:23 PM
Is the LiFePo4 batteries you mention the same (but different size!) as LiPo used in remote control helicopters?

There seems to be a fair amount of care taken when charging them - fancy chargers and "charging bags" used to control explosion risk.

My unqualified opinion is that bang for buck includes: cost, capacity, frequency of use and weight.

If someone has the cost of the different batteries (just a typical ballpark figure will do) it would be good. I would hazard a guess and say the lead acid cranking battery would be cheapest. How many of them can you stuff for buying even a modest deep cycle one?

I reckon buy at least two of them, and a quality charger to treat them right when you get home. Some people may have room for a generator to recharge them when needed. Set up a voltmeter or some sort of alarm to let you know when you get to 50/60% or whatever criteria. Then start generator, or even the vehicle.

Cranking batteries wouldn't complain if you actually had to use them for cranking either.

Also mentioned is making better use of the power with led lights and low current devices. Make some shade and airflow for the fridge

Cuppa
6th July 2013, 02:55 PM
There are indeed many ways to utilise power whilst camping TD, & most certainly finding ways to use less power is a very good strategy. However this doesn't help those who need or have an 80 litre plus fridge. It does seem however that many folk buy large fridges on the basis of their size without first thinking about the amount of power which will be required to run them. 80litre & 100 litre fridges which seem like a good value at time of purchase can quickly become far more expensive when their power requirements are met.

All too often the same old bullshit about how long such fridges can be run on 100ah batteries gets regurgitated. It makes no difference to me, but I have to admit to finding it difficult to sit by & watch misinformation spewed out as it misleads the hopeful & unwary, costing them their hard earned, & not giving them satisfaction. I can understand why such misinformation is perpetuated by fridge manufacturers, they want to sell their fridges, but why folks who are end users often perpetuate the nonsense I just don't know. The only reason I can think of is is that for some obstinate refusal to accept that they, like many others got suckered is easier than accepting reality.

If a Waeco 80 litre fridge uses an average 2.9amps (Waeco's figure) over a 24 hour period it is going to use 69.6ah. Even if the 100ah battery it's running off is fully charged (which with most VSR type dual battery systems it won't be) that is still only 24 hours usage.

No way can it last 3 days, not unless the owner has access to some sort of special magic not available to mere mortals.

The OP does have an 80 litre fridge & asked about a replacement for his probably rooted 100ah battery. I have tried to explain why it is rooted. At around half way through the three days the the so called battery protection setting of the fridge would have turned off the fridge. Chances are the cut out threshold is under 11v, this isn't battery protection, it's well into battery killing voltage. Fridge manufacturers persist with this nonsense because it suits them. At least the better fridges have a high, medium & low battery protection setting. The High setting has some chance of protecting the battery from over discharge, but this would mean the fridge would run for much less time until cut out.

When the fridge cuts out, the battery voltage slowly rises again until the fridge says " ok, enough power" & starts up again, sucking yet more out of the already half dead battery. This continues until the battery gives up. (With LiFePo4 a characteristic is that the voltage doesn't drop as capacity is used, they hold their full voltage until about 98% discharged - this is why it is often said that 100ah of LiFePo4 is equivalent to 200ah of conventional battery - that and the fact that such discharge does the battery no harm).

The bottom line is that if you want to run a fridge which uses 70ah in 24 hours you need the capacity to do so, either that or get a smaller fridge which uses less power. If the decision remains to run the big fridge and to carry sufficient battery capacity to do so then LiFePo4 offers one alternative to conventional wet & AGM batteries for similar outlay cost, & are cheaper in the long term. In car charging (smart charging not needed with LiFePo4) and/or solar can both reduce the size of the battery bank needed (dramatically) and the length of time the user can use the fridge off grid.

Currently it would be possible to run an 80 litre Waeco pretty much indefinitely with a DIY 100ah LiFePo4 battery bank (weighing around 18kg) in conjunction with a 120w solar panel & a conventional (VSR type) dual battery setup + data logger , for an all up cost of under $1000.

Cuppa

Cuppa
6th July 2013, 03:37 PM
Is the LiFePo4 batteries you mention the same (but different size!) as LiPo used in remote control helicopters?

There seems to be a fair amount of care taken when charging them - fancy chargers and "charging bags" used to control explosion risk.

My unqualified opinion is that bang for buck includes: cost, capacity, frequency of use and weight.

If someone has the cost of the different batteries (just a typical ballpark figure will do) it would be good. I would hazard a guess and say the lead acid cranking battery would be cheapest. How many of them can you stuff for buying even a modest deep cycle

Not certain, but I think LiPo are different to LiFePo4
Many types of 'lithium' batteries, some more volatile than others.
Fancy battery charging /management systems CAN be done cheaply DIY, & as I understand it are not actually that fancy.
Some folk need the reassurance that comes with an expensive proprietary system, some are happy with a time proven DIY system ..... Horses for courses.

AGM battery 200ah - around $450 for a decent one
LifePo4 100ah (equivalent to AGM 200ah) $520 (see link posted earlier) has longer life & less weight, & does not deteriorate/lose charge over time if not used.

It is fair to say that early adoption of new technologies is not for everyone. I'm not trying to 'sell' LiFePo4, I don,t even have any myself, just letting folk who might be interested know that there is an alternative available which would suit the needs of less space, less weight, & similar outlay cost for 4wd purposes.


Cuppa

BigRAWesty
6th July 2013, 05:47 PM
Coming from a model background Lipo and life batteries are widely used.
A single cell Lipo crates 3.6V and life 3.2v. So to get your 12v you need to add multiple cells in series. Now this is ok for discharge, but come charge time you need to monitor each cell and charge, or "balance" each cell independently to eliminate the risk of over charge.
Lipo and liFe are very sensitive and will ignite if disrespect.

Now uses. Lipo are good for high voltage quick discharges..
LiFe are a slower discharge but can be drained a lot further without damage and risk of cell rupture.

So although the technology is there, converting it to cars is a big job.
You need a charger that not only steps 12v to the required voltage but also has the ability to charge each cell individually to ensure each cell charges to 100% and not over charges..

Our model charges for an average 5A/h 3cell Lipo (11.1V) your looking at $50+.
Now you could get a 6 cell charger which gives you 10A/H. Still f all.

so thus is why you don't really see Lipo and LiFe in automotive. Its just not cost effective.. and the fact that and damage to cells in a crash results in a largish fire ball and lots of smoke..:p

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

threedogs
6th July 2013, 05:56 PM
Price wise a half decent deep cycle battery will cost $350 that's for a yellow optima job
Some consider them top of the tree {not me} Full River do a great battery as well but will cost maybe $450
But you may find a price of $280 will get a battery that will suit your needs , shop around.
Stay away from re birthed batteries, IMO.
A lot depends on use, place etc

Cuppa
6th July 2013, 10:48 PM
Coming from a model background Lipo and life batteries are widely used.
A single cell Lipo crates 3.6V and life 3.2v. So to get your 12v you need to add multiple cells in series. Now this is ok for discharge, but come charge time you need to monitor each cell and charge, or "balance" each cell independently to eliminate the risk of over charge.
Lipo and liFe are very sensitive and will ignite if disrespect.

Now uses. Lipo are good for high voltage quick discharges..
LiFe are a slower discharge but can be drained a lot further without damage and risk of cell rupture.

So although the technology is there, converting it to cars is a big job.
You need a charger that not only steps 12v to the required voltage but also has the ability to charge each cell individually to ensure each cell charges to 100% and not over charges..

Our model charges for an average 5A/h 3cell Lipo (11.1V) your looking at $50+.
Now you could get a 6 cell charger which gives you 10A/H. Still f all.

so thus is why you don't really see Lipo and LiFe in automotive. Its just not cost effective.. and the fact that and damage to cells in a crash results in a largish fire ball and lots of smoke..:p


Hi Kallen, you are correct about the need for monitoring each cell when charging. This is part of the automatic cell management system which has been developed & successfully used in over 50 RV's ( & growing) with battery banks of up to 800ah. 200ah to 400ah are the most common bank sizes. The battery management system can be put together for under $75 making it cost effective. It has been done so that the system is fail safe as well as low cost & utilises readily available & proven technology. This flies in the face of much of the 'accepted beliefs', but the proof of the pudding is in the eating & the beliefs that have been challenged are now changing. The cynics have started to accept that what they considered not feasible is, albeit having been developed by folks without letters after their names. A few folks with egg on their faces have since wanted to gain the knowledge developed by these pioneers, who understandably have taken great pleasure in refusing them. Hence a continuing 'secretiveness' about it all.

The folks have their own private online forum on which the details of the battery management etc are available. Membership is dependent upon agreement not to sell or share this info, & this has come about because of the negativity aimed at the folks involved & the desire of some to exploit for personal profit. I know a number of the members of that forum but am not a member myself. I do however know a number of these people who have been running their LiFePo4 RV systems both safely & successfully since a couple of years before the technology was adopted by Kimberley Kampers. I have seen their vehicles & know several who live full time in their vehicles, with capabilities that their cynics can only dream about. eg. running air conditioners from battery systems...... all without expensive proprietary battery management systems or fires & explosions.

Initially the folk involved were open & sharing with their knowledge as they worked through how to do things, but the naysayers were so vehement & persistent, as can occur on online forums, that eventually that sharing was withdrawn & the private forum formed.

The following two quotes from a friend of mine who runs the forum.


It's the understanding as a result of learning that costs little yet is priceless that makes all the difference About the only easy way to make a comparison for that bit is, buying a border collie pup doesn't mean you have just purchased a champion sheep dog. The cost of training it yourself is minimal, the knowledge and patience to do it is priceless. Setting up and using a lithium battery pack goes along the same lines, without the knowledge you need someone to build a fail safe system to protect the battery, then you are paying for someone else’s time and knowledge and that rarely comes cheap.
The private forum has the needed information but comes with a condition that what you learn is for your personal use, not to be shared or published outside the private forum.


All lithium technology batteries are li-ion, just as calcium, flooded, agm, gel, starter, deep cycle are all lead acid batteries, it's just the way they store and release their energy, I won't even attempt to explain how that happens with Li-ion batteries here, the eyes would roll and everyone would nod off
LiFeP04 or lithium ferrous batteries are the safest of the breed, they don't burst into flames, tortured they will release a vapour a bit like boiled petrol but it dissipates or settles out into droplets as soon as it cools. The battery is stuffed if you torture it that far, it's the electrolyte boiled away, there is only about a tablespoon in each cell packet and you can't replace it. The alloy of these metals combined make them unaffected by water where pure lithium reacts badly in water, you can dead short it or shoot a hole through it and all that will come out is this boiled electrolyte vapour.
The ones that caught fire in the Boeing 787 were lithium manganese, nearly as unstable as lithium polymer (LiPo) they need to have your full attention when charging them and if you very fast discharge them, they suffer thermal runaway and burst into flames if you stray outside the safety zones even a little bit. Lithium ferrous don't do any of these things, but a big wander outside the safety zones will kill them, just like a lead acid battery, but no explosive gas is produces, just the quick dispersing petrol like vapour but it is flammable while in the vapour stage just the same.

The fail safe nature of the Diy battery management system they have developed ensures full safety.

My mate has given me permission to pass his contact details to anyone who has learned enough to decide that they want to set up a LiFePo4 system for themselves, but warns there is a waiting list to join their forum because of a preference to assist folks on a one to one basis.
Cuppa

BigRAWesty
7th July 2013, 05:25 PM
It is possible, by all means. But the risk of what happens when overcharge or over discharge is a big factor I think. And it can happen.. no matter how fool proof your system is, and no matter how many fail safes you have, it only takes one small wire to break on a corrugated road and bag she goes..
Over charge or discharge a lead acid sealed battery nothing happens.
Do the same with a Lipo or life battery... Well... You tube Lipo fire..
But the burn of a cell is only 5-10 seconds. But its a chain reaction.. so if you have 20 cells, you can quite safely wave bye bye to your vehicle..
Also having this chemistry in a moving vehicle introduces the risk of eruption in a crash.. or any situation where a cell can be damaged..


So yea, I'd love to run LiFe batteries, but ill stick to lead acid for the time being.. :D

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

BigRAWesty
7th July 2013, 05:55 PM
I just reread the first post and I believe we have strayed.. really.. us noooooo.... :p

Anyway. Best battery.. I got my 120A/h lead acid battery for free.. was 'stuffed' according to the trucking company.. but they turf them as soon as they look like not performing.. as they can't afford down time of a call out..
So the turf out perfectly good batteries.. sure, not new, no warranty and you may get a dud, but they are perfectly fine for our uses.
Mine is 3 years in my possession now, abused the crap out of it.. left uncharged for months, over discharged and left it on cement... Lol
Now its in the car and can carry a 55 ltr weaco and led lighting for 3 days.. so I have no issues with my freebie.. when it starts to fail, ill go get a new one..

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

ozzyboy
7th July 2013, 06:14 PM
was thinking of getting something like this.

http://www.ebay.com.au/itm/Thumper-Redback-Extreme-120-AH-AGM-SLA-Battery-Deep-cycle-12-Volt-Caravan-4WD-/111109909375?pt=AU_Electronics_Batteries_Chargers&hash=item19deaaab7f

my concern is, I had a 120ah battery, and the thing didn't last 12 months. Wife bought it while we were in rocky, lost receipt :(

Cuppa
7th July 2013, 06:44 PM
was thinking of getting something like this.

http://www.ebay.com.au/itm/Thumper-Redback-Extreme-120-AH-AGM-SLA-Battery-Deep-cycle-12-Volt-Caravan-4WD-/111109909375?pt=AU_Electronics_Batteries_Chargers&hash=item19deaaab7f

my concern is, I had a 120ah battery, and the thing didn't last 12 months. Wife bought it while we were in rocky, lost receipt :(

By all means go for it mate, but don't expect it to last any better than the previous one if you intend to to run it flat by trying to run an 80 litre fridge for 3 days at a time without any additional charging input. Under such use 12 months lifespan would be good.

These deep cycle batteries are NOT designed to be run until flat before recharging if you want them to last - regardless of what anyone might tell you.

Cuppa
7th July 2013, 06:56 PM
It is possible, by all means. But the risk of what happens when overcharge or over discharge is a big factor I think. And it can happen.. no matter how fool proof your system is, and no matter how many fail safes you have, it only takes one small wire to break on a corrugated road and bang she goes..


A failsafe charging system takes into account that wire breaking ....... or it wouldn't be fail safe.

BigRAWesty
7th July 2013, 06:58 PM
By all means go for it mate, but don't expect it to last any better than the previous one if you intend to to run it flat by trying to run an 80 litre fridge for 3 days at a time without any additional charging input. Under such use 12 months lifespan would be good.

These deep cycle batteries are NOT designed to be run until flat before recharging if you want them to last - regardless of what anyone might tell you.

That's the thing though. Its free. So abuse the Hell out of it and find there limits before forking out your hard earned..

Kallen Westbrook
Owner of
Westy's Accessories (http://www.nissanpatrol.com.au/forums/showthread.php?15134-Westy-s-Accessories.-A-small-back-yard-builder.)

Cuppa
7th July 2013, 07:11 PM
I just reread the first post and I believe we have strayed.. really.. us noooooo.... :p

Anyway. Best battery.. I got my 120A/h lead acid battery for free.. was 'stuffed' according to the trucking company.. but they turf them as soon as they look like not performing.. as they can't afford down time of a call out..


Strayed off topic? Not really. All we have talked about is a) why trying to use a 120ah lead acid battery to run what the OP wanted to run for 3 days at a time will ensure the battery's early demise & b) discussed an alternative type of battery - which I accept is not for everyone at this time, but would do what is wanted from a battery of the size to fit where the 120ah one fitted.

As I said in a previous post the best sort of batteries ozzyboy could get would be ones like your ex trucking company one - i.e. cheap. Note however my use of plural. One would still be insufficient.

Your smaller Waeco plus led lighting would use half what an ozzyboy's 80 litre Waeco + led lighting + battery chargers would. Very different scenario.

Cuppa

ozzyboy
7th July 2013, 07:12 PM
I should of mentioned in my first post, that I do have a 120w solar panel that I use. The battery still ran completely dry

ozz

Cuppa
7th July 2013, 07:24 PM
I should of mentioned in my first post, that I do have a 120w solar panel that I use. The battery still ran completely dry

ozz


Ahhhhh.....<slaps head> ... that does rather change things. Assuming 3 things, then a 120ah battery should be up to running your 80 litre Waeco over a 3 day period.
1. that there is sufficient sun.
2. that you have heavy enough cables with good battery connections connecting the panel to battery (not the skinny cables & feeble crocodile clips that many of the cheap panels are supplied with) to ensur you are not losing your panel's input to voltage drop.
3.That your panel has a blocking diode to ensure that your battery is not discharging through the panel at night (essentially an electrical one way valve - not alays needed when good regulators are used, but if using one of those regulators supplied with the panel - who knows?).

Cuppa

ps. 4. Also depends on what you mean when you say 'battery chargers' - depends what you are charging. e.g.. if charging a laptop this could pull 5 to 7 amps on some, if phones not a lot (but could still add up to significant amounts if left plugged in all the time). For charging, 'timing' can also make a difference. Possibly better to do the charging in the early afternoon once the solar has had a chance to replenish what the fridge has used overnight & the sun is still shining, rather than in the evening, making the most of the available slar input.

ozzyboy
7th July 2013, 07:28 PM
don't know much about solar panels. I remember buying it because a) I got a pretty good deal and b) a mate told me it was a good 1, with a mppt?? regulator
it does have thin cable and alligator clips tho

ozz

Cuppa
7th July 2013, 08:07 PM
Forgetting the LEDs & battery charging

Waeco needs around 75ah per day

Typical scenario
Arrive at camp after 3 hour drive - 10ah already used (assuming fridge was pre-cooled on mains & not put on battery until just before you left)
Put out solar panel before setting anything else up & catch 3 'sun hours' worth of input before dark - 20ah generated, enough to run fridge & reach evening with battery close to full charge again.
2nd 24 hours 75ah used. 35ah generated (5 sun hours @7 amps) balance in battery = 120ah - 75ah +35ah = 80ah
3rd 24 hours 75ah used 35ah generated - balance in battery = 80ah - 75ah + 35ah = 40ah

40ah = 1/3rd battery capacity. Sustainable for short periods. Ok if you put battery on charge as soon as you get back home. Use like this should see battery last better than than what you have had.

BUT..... you can see it is marginal. Toss in the LEDs & battery charging, & a cloudy day & you would be well into battery killing territory. A second panel would make a huge difference & take the worry out of running out of power or killing the battery.

And it really is worth using heavier cables because it is fair to say that that the skinny cables you have will not be allowing the 35ah per day input from the panel as I have used above, potentially a LOT less.
To calculate cable size, dependent on length, see http://hobohome.com/news/?p=581 at bottom of page. 'Round up' (not down) to nearest size. Note that size relates to the copper core in Sq mm, not to automotive cabling size (which includes insulation)

nissannewby
7th July 2013, 10:24 PM
CAT batteries are awesome value for money and have a great warranty ozzy check it out. 4 years all up, 1st 2 years they replace, 2nd 2 years they will go halves.

I know its not what your after but I bought the biggest battery CAT make, 1500 CCA and will run the fridge for a week, weighs 60kg though lol. Only cost $360

alfonso
26th July 2013, 05:32 PM
75 ah seems a lot for a fridge in a 24 hour period . 3.125 amps per hour As power is only consumed when compressor is working I thought it would be much less

Cuppa
26th July 2013, 05:54 PM
75 ah seems a lot for a fridge in a 24 hour period . 3.125 amps per hour As power is only consumed when compressor is working I thought it would be much less

Hi alfonso,
80 litres is a big fridge. Waeco themselves claim an average of 2.9Ah. Average meaning average hourly use taking into account the compressor cycling on & off. 2.9 x 24 = 69.6. This figure is based on the fridge section being maintained at 5 degrees.C in an ambient temperature of 32 degrees.C. Often folk want to run their fridge cooler than this, & in summer ambient temperatures can often be above 32 deg.c, particularly in the back of a car. Both these factors will increase cycling on times & thus increase average power consumption. Add to this that most fridge manufacturers are , shall we say, optimistic with their claimed figures, I think the possibility of 75 Ah per 24 hours to be realistic, & possibly even a bit low.

Cuppa

threedogs
26th July 2013, 06:06 PM
75ah does seem a lot , but battery wise look out for 100ah batteries from "UPS" systems as in bank shutter systems and hi-tech computer places.
you can usually pick them up for less than half price. Pic is of my AUX battery, these same batteries are used out in Port Phillip Bay on
the marker beacons. It's 115ah

those CAT batteries sound like the cats whiskers no pun intended.
some use their coolant too, but a bit aggressive on the modern motors
@ ozzyboy on a good sunny day you should be returning around 6 amps
back into your battery.

Cuppa
26th July 2013, 06:34 PM
75ah does seem a lot

Sheesh!
http://www.nissanpatrol.com.au/forums/images/imported/2013/07/109.jpg (http://www.flickr.com/photos/cuppa500/9367305473/)

The Waeco 80 litre uses the Danfoss BD50 compressor, which when running uses 70 watts. Watts divided by the system voltage equals amps. 70w divided by 12v = 5.83amps. 5.83 x 12(hours) = 69.6 amp hours.
This equates to a 50% duty cycle which would be about right, AND surprise surprise the figure is identical to that given by Waeco!

In hotter conditions, or with the fridge turned down to what most folks prefer for their beer, a higher than 50% duty cycle would be expected.

Cuppa

threedogs
27th July 2013, 10:05 AM
I hear you Cuppa but I can only go on what happens in the real world like at camp, I could sit next to my engel 40 all weekend and doubt it would run for 1hr at a time {cycle}
On a very hot weekend my Engel lasts 3 days before I'll need to think about charging the battery, never have yet.
Bear in mind I only use my Engel for Food and a few soft drinks, if used as a beer fridge reckon I'd be lucky to get 1.5-2 days from my battery.
That is why I use an ice box for drinks for 4 blokes [96 cans], and if required I can drive recharging my aux on the way to town to get ice. I think real world scenarios on what works and what
doesn't is best advice on these forums. then what works for me may not suit others, then we modify to suit.

Cuppa
27th July 2013, 12:36 PM
In your real world you are comparing apples to oranges TD. Primarily a 40litre fridge simply cannot be compared to an 80 litre fridge in terms of power consumption. Secondly the Engel has a different type of compressor. Thirdly it is possible that your Engel has a different thickness and/or type of insulation. Fourthly by your own admission you choose to use your fridge differently to many people, which reduced power consumption.

Suggest you might do a little research ...... Look up Engel's rated power consumption for your fridge at X degrees.C in an ambient temperature of Y degrees.C & compare the figures to an 80 litre Waeco. When you've done that report back what you find!

Cuppa

P4trol
27th July 2013, 01:17 PM
Is it the danfoss (as opposed to what is in the engel) compressors that actually use more current as the battery voltage gets lower?

threedogs
27th July 2013, 02:25 PM
rather than listen to waeco marketing hype I'll listen to my fellow club members for "real world" figures not laboratory controlled figures .
wasn't trying to compare my little engel to an 80 ltr waeco, just relaying what works for me so , enough said I reckon,
@ ozzyboy what are the main duties of your waeco, just keeping food cold and some throffies, or just drinks and 6 snags.?
understanding what or the way you use it may help find an answer. anyway going away for a while hope you find your battery

Cuppa
27th July 2013, 04:38 PM
Is it the danfoss (as opposed to what is in the engel) compressors that actually use more current as the battery voltage gets lower?

Haven't heard that before.
Danfoss (now called Secop since a company takeover in 2010) are the most widely used low voltage compressors in camping, RV & portable medical fridges worldwide. Commonly used are the BD35 & the larger BD50 compressors.

The Sawafuji swing motor used in Engels is almost as efficient, & the Domus (Chinese I think) used in many of the cheaper fridges, less so I understand.

The better Waeco's use a Danfoss, whilst their cheaper models use yet another Chinese sourced compressor - 'Wanbao', which may or may not be the same as the Domus. Either way the Wanbao & the Domus have a 2 year warranty, whereas the Danfoss/Secop has 5 years.

@ TD ... Why would Waeco's marketing hype suggest that their product was actually less efficient than it's "real world" performance? Wouldn't be 'hype' would it? I'm not sure why you are having trouble accepting the matching figures from both Waeco & Danfoss.

P4trol
27th July 2013, 09:11 PM
Gee, I was hoping you had heard of it. I had to do more research!

So there is two types of motors. The the rotary one (that the DANFOSS style uses) and sawafuju. The rotary ones suffer from a large current draw on start up. The sawafuji one doesn't.
When the rotary one gets hot or runs on lower voltage, it is less efficient. The motor goes around slower and creates more heat. This makes it hotter, and less efficient.

Not very well explained, I know. The sawafuji motor is different, in that it will work like a swing. (pause)

If you think of a little kid pushing a swing. Not the coordination, just the tiny pushes they are capable of. Given the right timing, pushing the same as they would be able to push, the swing will soon be at a fair height. The sawafuji operates on this principle, able to start up with small pushes (say from a battery of less than optimum voltage. The following link is some Engel propaganda.

http://www.engelaustralia.com.au/about_SwingMotor.asp

As pointed out, we tend to operate our fridges in less than ideal conditions. This means the manufacturer special aren't real life, although if you had the same testing conditions, I have no doubt you would come up with the same results. I do think the Engel has the edge in the lower voltage conditions.

Cuppa
27th July 2013, 10:04 PM
Fords & Holdens, Patrols & Landcruisers, Engels & the others. :)

I certainly agree that manufacturers specs are not the same as real life, but I wouldn't agree that the real life figures are actually better than the manufacturers specs, which is why I've previously suggested that the manufacturers specs are at best optimistic. (some of the other stuff they tell you is at best very misleading, but it helps to sell fridges - check out Waeco's FAQ page).

What you say about the efficiency of the the two diferent types of motor may well be the case but it leaves me wondering why it is that there are many many more danfoss powered fridges out there than Engels, & also why it is that Engel give only a 3 year warranty, vs Danfoss' 5 year warranty?

Could you share the link with the info about the 'problems' with rotary compressors.

I guess at the end of the day efficiency is about how the whole package works. I can see from what you've reported for example, that an Engel may be better at lower voltage than a rotary, but this will only come into play when the battery capacity is getting low & the voltage dropping off. As per my posts elsewhere about ensuring good battery life this is a situation best avoided, & thus, for those who try to ensure optimum battery life, having a compressor which is more efficient at those lower voltages is of no benefit. If getting the longest use out of a battery charge at the expense of battery life is the aim, then there may be a case for choosing an Engel. As for getting hot causing less efficiency in the rotaries, I have run our fridge in the bus at ambient temperatures up to 47 degrees quite successfully. Whilst at that sort of temperature the fridge cycles on more often & thus uses more power, but I have never observed it to be drawing more current whilst running. It always uses the same whilst running whatever the temperature ........ although I'll qualify that by saying my monitor only reads to one decimal place, so it is possible that there have been minor differences I have not seen.

P4trol
27th July 2013, 11:18 PM
My guess is there is a patent on the Engels, which they aren't licensing.

Most of the literature I see on the danfoss compressors is that it is now controlled by an electronic board. One bloke believes that prolonged low voltage kills this board.

The waeco UK Site says it happens to all compressors.

"
Also, if the supply voltage from the battery becomes too low, electronics and motors tend to overheat. This occurs with all electronics and all motors no matter who the manufacturer is. And that is why we do not allow this to happen to WAECO products.
"

From http://www.waeco.co.uk/page.aspx?page=faq&s=4

Also on the same page, some models (or maybe all models?) have a 'my beer isn't cold enough switch' (emergency) which bypasses this elec-trickery controlling/protecting the compressor. You are on you own then. I was unaware of the electronic protection in my earliest post.

I'm unaware of the reason for warranty time differences. You know how we only have so many heartbeats in a lifetime...

Cuppa
28th July 2013, 08:45 AM
My guess is there is a patent on the Engels, which they aren't licensing.



Ah but............;)
Patents haven't stopped designs being copied in overseas countries & then imported to compete with the patented product. It's possible they exist, but to date I haven't seen or heard of an Engel copy.
As it is both types of compressors do a good job & have good reputations, & the issue with low voltage only come into play when a battery is being 'abused', so with battery protection built in to the rotary compressors it's not really an issue.

I'm not really wanting to be argumentative, but rather, hope that this discussion may be helpful to others down the track when they are thinking of buying a fridge, which after all is not a small investment. It is my belief that many fridges are purchased on the basis of their capacity & what will fit into the available space, without necessarily considering what will be required to run it. Such decisions are influenced by misleading statements from Manufacturers like can be read here (http://www.waeco.com.au/cfx/faq.asp) (check the 'How long will my refrigerator keep running for on my battery? section) & then compare it to here (http://www.portablefridgesonline.com.au/fridge-faqs/fridge-faq-battery-and-electrical-setup.html), (How long will it run on a battery for? section).

Returning to the power consumption of the 80 litre Waeco, I note from the UK waeco page link in P4trol's most recent post that they provide a more comprehensive table of power consumption for all of their models than I've seen on our local Waeco site.
http://www.waeco.co.uk/page.aspx?page=powercon&s=4
In this the 80 litre fridge (CF80) specs say 5.5 amps current draw when running, which is what I would expect, and a consumption of 84Ah in 24 hours, suggesting it has a higher than 50% duty cycle, & this is at the slightly lower (than on the Aussie site) ambient temperature of 30deg.C. Not hard to imagine this rising to 100Ah on a 40+deg.C day. No doubt some extra insulation, even just a transit bag, would improve this.

I recall reading somewhere that not only the volume of the fridge, but it's shape (dimensions) also contribute to it's overall efficiency. As I recall the most efficient portables are 40 litres & below & I can't remember what the 'best' shape is. Tall & narrow, or low & wide? I'm guessing the former would be the more efficient, which if correct also doesn't sit in the CF80's favour, it being low & wide. This shape makes it more convenient to use (less rummaging around to find what you want), but at a possible price of higher power consumption.
Arguably the best portables on the market, the Trailblaza's (http://www.norcoast.com.au) have a combination of extra thick insulation, a tall & deep shape & a Danfoss compressor. However the extra insulation (up to 5" thick) makes for a fridge that is just too bulky for many, & they are priced way above the more commonly available brands too.

Cuppa

rex
28th July 2013, 10:40 AM
do agree with u cuppa just fridge size I run my 40 litre engel on 100 ah batt with 80watt solar panel was out for 10 days battery never got below 12.5 volts the whole time could not be happier with the set up

threedogs
28th July 2013, 10:49 AM
Same sort of set up I use and like you could not be Happier..

lightnites
25th August 2013, 09:02 PM
I agree that it all comes down to what works in the field, not "on paper" figures.
I could run 2 x Ironman 50L fridges (one on freeze) off a 120ah glass mat battery matched to 2 x fold out 80w solar panels, indefinitely.
That's with full sun (in the Kimberley) and fridges with transit bags in shade. Panel input is more than current draw. Simple!