best value for money battery for camping?

[ozzyboy]

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]

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]

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]

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]

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]

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]

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?...=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]

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]

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]

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