AGM battery

Agree with Bob, I've had mine for 3 years and they are going great. They have seen some extreme heat and have been down to 10.2 V a couple of times.
They are not cheap, but if I can get 8 years like Bob I will be happy.

Andy

I agree with Bob's first point, too.

How are you charging your second battery? Off an ECU or temperature regulated alternator? If so, it will never get the charge it needs to last, particularly if it's down the back or in the camper: a DC-DC charger would fix that.

How's the wiring? If your second battery is in the engine bay, minimum 8 gauge cabling, IMO. If it is down the back, minimum 6 gauge.

Are you running cabled negatives back the the crank battery or a manufacturers chassis earth point, or have you made your own chassis earth points? Are the connections clean and good, especially the chassis earths?

Do you have soldered or crimped lugs and terminals? If crimped, are they all still good? None loose, dirty or corroded, particularly those that regularly get wet?

Do you regularly discharge your battery below 50%? Routine discharges below 50% will shorten the life of a battery, even deep cycle batteries which are designed for deeper discharge. But not ALL the time. And if you do, they have to be properly recharged ASAP (multi stage mains, solar or DC-DC charger).

Etc

Cheers

Like Bob and Andy, I have an Optima Yellow Top (D34).
I have mine fitted as a second battery under the bonnet of a 120 Series Prado and have had mine for two and a half years and it is going strongly DESPITE my attempts to kill it.
The main practice that I must rectify is the charging from the alternator. Unfortunately, the Prado alternator only charges in the low 13s voltage wise. The D34 Optima needs a minimum of 13.65v up to 15.0v from the alternator.
I intend to fit a DCDC charger (at least 25amp capacity) to rectify this situation.
I stress, the battery has been brilliant - it is the charging regime that is letting me down.

Harry

The use of a booster diode will correct the low voltage problem in the prado, refer to my add in the classified section.

Cheers
Leigh

have a look at these diode boosters Harry. Derek Bester at Sidewinder does them for $35. You just swap existing fuse for one of these. Not saying it does what a dcdc charger does but it has made enough difference on mine to keep my aux battery fully charged. Mine's a Prado 120 too. I was losing charge on it all the time until I put this in. 2 minute job.

http://www.sidewinder.com.au/page226.html

if you just google "alternator booster diode" you'll find plenty of discussion about them - Pradopoint also has plenty of stuff to read up.

Agree. I fitted 2x105AH Supercharge allrounders as my auxillary batteries back in December 2008 and they are still going strong. I have installed a Projecta DC20 12Volt to 12Volt changer in the tub of my ute and close to the batteries and this has worked exceptionally well for me.

Whilst the diode addition will boost the overall voltage of the alternator output by approximately the voltage drop across that diode, and whilst it will improve the charge characteristics of a single battery set, it will not make any appreciable difference to the charge going to your remote battery.
The reason for this is that the alternator regulator is sensing the voltage at the terminals of the crank battery.
This voltage will rise quite rapidly to that of the alternator, and 0.6v extra does not take long to achieve.
The remote battery, which is very likely to be some fractional order of magnitude larger than the crank battery, will require much longer to achieve a full charge but will exhibit a surface charge voltage similar to the alternator output fairly soon after charging begins.
Voltage drop in the connecting cables will also be a factor.
Now the problem.
The regulator, which is a constant voltage device, will attempt to maintain the alternator voltage at its set level independent of load, it does this by adjusting the output current just enough to satisfy those loads and to keep the crank battery voltage at the set level. When the battery reaches this level, the regulator ramps the output down until the voltage again begins to decline whereupon it ramps it up again etc. etc.
Once the crank battery has reached the set voltage, whether that be 0.6v higher or not, the regulator will cut back the alternator's output
to just what is required for the loads.
The remote battery will not get the optimum charge current that it requires for timely charging and, while many people think their remote battery is fully charged (because they only relate to the surface charge voltage), that is generally not the case.
A DCDC charger by contrast, is a staged charger that carries out the bulk of its duties in constant current mode which delivers a faster charge to the remote battery, it also takes care of the voltage drop problem.

For under bonnet applications there is no difference with charging directly off the alternator or a DCDC charger. If the aux is located in a caravan then yes the situation would have to be looked at.

A DCDC charger only acts as a constant current source to protect the charger it does not deliver a faster charge.

Example a ctek will act as a constant current source limitings its output current to 20A to protect itself, ie the charge voltage will start off slightly above the batteries terminal voltage and then slowly increase until the battery reaches approximately 80% SOC or 14.4V, it will then switch to constant voltage mode. It would take the ctek around 3 hours to bring an Optima upto the 90% SOC mark.

Whereas the alternator will reach 14.4V within a few seconds of the alternator starting to charge and is not current limited, the Optima when charged directly of the alternator would only take around 50 minutes to reach the same SOC.

Hi All
I also have 2 optima D34 in my Pajero. Have had them for 4 years and have been brilliant . Had them survive the Simpson in 43 C driving at 15kph for 2 days!! They must have been super hot under the bonnet. I also have then in 4.5ltjohn Deere tractors and last anywhere from 6-8 years . Sure they are only 55 amp hour but if u are moving regularly they are fine Cannot speak highly enough of there performance
Cheers
Greg

Bonz, what sort electricty does he have? Thanks in advance. John

John
They are very expensive electron filled units. The dense type of electrons too.

I will point him to this post and let him explain, but they're pretty trick

G day Bonz
Been a while since I have tormentened fellow members of ExplorOz, but we plan to do the Anne Beadell, and the Connie Sue Highways, in July, and August, and although my batterys are just 18 months old, they are definately on the way out.
Sad part is that I drive daily to work, 90 km round trip, and a few hunting trips up in High Country. There has been one trip to Capy York, but nothing too super "corrugated"

May have to look at the Optima AGM's

Ches Bucky

Hey Bucky, I wouldnt have thought that that would be an issue for batteries these days? M ine have been in the Patrol for ages and are both happy.

Evening Bucky.

Just became aware of Bonz suggesting that I have the be all and end all of batteries.

Short answer is I do have such animals, three (3) of them to be exact. They are 110AH Lithium Ion batteries and cost me AUD$950.00 ea to get them to my front door from China.

If setup correctly, they do not over heat, do not over charge, charge to to a 100% in ridiculously short amount of time, do not vent gas of any kind, weigh a 1/3 of the weight of a 100AH Lead Acid Calcium(LAC) battery, and are noticeably small in size compared to the 100AH LAC. They fully sealed and have no 'liquid or semi liquid' electrolite like other batteries.

I used these three as a battery bank for a caravan that I just recently sold, and will be used in some sort of RV that will replace the caravan one day.

They are leading edge technology developed for Hybrid cars and are available in 3 different models which allow for (a cranking battery (b) cranking/deep cycle battery and (c) Deep cycle only.

The price varies substantially (upwards) as each model has a different Battery Management Unit (BMU) for each of the different uses.

They have a critical charging regime that must be adhered to (nothing onerous) or else you can kill them pretty much instantly.

So! are they for your application - in a nutshell, MOST DEFINITELY NOT. Bonz gets starry eyed with technology.

Recommendation for your application :

Delkor 75Ah Cranker - R J Batteries, Hallam, Vic

CAT 100Ah or 75Ah Deep Cycle/Cranker - William Adams, Clayton

Regards

DD

There ya go, told ya he knew stuff.........

Bonz, how does one contact Dust Devil? Thanks in advance.

He is of the Dust John, but reply here and I may be able to rouse him

Bonz/Dust Devil, Am very interested in the Li-Ion batteries that you have purchased, looking to get a couple of these myself. Would be nice to chat with you and get your thoughts on them. Thanks in advance. John

John.

You can contact me on 0430 468 480.

DD

Garry,

Older model alternators charge at around 14.4V - 14.6V with the ambient temperature at around 22C.

DCDC chargers, Ctek chargers at 14.4V and Redarc at 14.5V, as you can see they are all more or less the same except that the DCDC charger is current limited to 20A (20A versions) to protect the charger from overloading. An alternator is not current limited so can charge the battery a lot faster up till around the 90% SOC mark if the battery will accept it.

Most normal lead acid and AGM batteries will charge happily at these voltages.

In the case of some newer alternators they charge at a lower voltage once the engine bay warms up, fitting a booster diode will restore voltages to near normal alternator levels.

As already mentioned the Optima's will happily charge directly of an alternator, they will go from 0% SOC to 90% SOC in around 50 minutes and are an excellent choice for under bonnet applications though not cheap.

Cheers
Leigh

the same

So ya batteries are not lasting long....yeh well.

look at how you are treating your batteries.

It is known that how batteries are teated has a very strong effect on their life.

I read a research paper a while back, where a particular well regarded stationary deep cycle battery was tested.
They proved that they could reduce the life of a battery known to last 10 years when treated well......(last within established specs).... to 60 days.
And that miss-treatment did not include over discharge beyond normal specs.

cheers

Hi Bantam
All I will say , in my application of vineyard tractors(15 all up ), all have optima, that Wet Cell batteries do not perform!! 3 years is maximum life if ur lucky
All were regularly topped up. Vibration is the killer.
Horses for courses tho I will admit
Cheers
Greg

You may be using optima batteries now, and they are a fine product within their limitations....but compared to what.

what batteries where you using in the past.

AND this is the thing.

All to often people make comparisons that are simply not fair.

All too often people are comparing some sort of up market or premium battery with basic technology......not even current state of the art for batteries of the type.

Of course an optima (or any other premium battery) is going to look good against early 20th century lead acid technology, which is still in the market in every mass market brand in the low end of the range.

Then there are the well established brand names, that everbody recognises, that everybody assumes are good quality.....But simply do not make a good battery by todays standards.

NOW....AGM is a reasonably recent marketing term, starved electrolite batteries or nonspillable batteries of various types have been around a very long time.

I'm old enough to remember when the "Gates cyclon battery" first hit the electronics trade press.......this is the technology that has become optima and other spiral cell batteries...( there are others).....the thing is I dont remember the term AGM being in use then.

The truth is all the various changes to the lead acid battery mechanically and chemically that allow an AGM or other " sealed battery", can be employed in a wet cell battery and are.

In fact there are a couple of battery manufacturers that sell the very same battery structure in a variety of forms, ranging from a fully flodded battery thru to an genuine AGM battery, with the only change being the chemistry of the electrolite and how much is in the case.

NOW the optima or spiral cell battery is not a typical "AGM" product and has some significant advantages over other "AGM" batteries...but it also has a couple of drawbacks.

cheers

what about the "marine batteries"? Aren't they supposed to withstand the bouncing around in the waves and maybe corrugations?

As far as the OP is concerned I appreciate it depends on how they're set up but that aside.....?

Yes indeed, you do well to mention the marine batteries.

A good quality modern marine or rugged construction battery is everything and AGM is and more.

A modern "sealed" marine battery has clacium in the plates just like most AGM.
A modern "sealed marine battery has a modified electrolite, just like all AGM.
A modern "sealed marine battery has plates either wrapped in glass mat or glass mat packed between the plates, just like all AGM batteries.

What a modern "sealed" marine battery has that AGM does not..is plenty of electrolite...this allows them to cope with temperature better.

The other thing a modern "sealed" marine battery also does not have is a high price tag.

In general they cost about half a similar AGM.........so, how come you can tip half the acid out and charge twice the price.

Now these "marine batteries" may also be sold as, 4wd batteeries, earth moving batteries or mine batteries.

In general they have better deep cycle tolerance, longer service life, higher capacity for size and better cranking capacity than similar sized batteries that do not employ the same technologies as AGM.

AND in an N70 sized battery you will not get more bang for your buck.

SO think about this...if you are flogging your battery, and you are going to kill it by treating it bad.....why pay twice the price for a battery that will not last any longer.

better still. in marine batteris you can afford twice the battery capacity....that means you will not have to cycle anywhere near as deep...this will make your battery last longer.

Now these marine batteries are not as narrowly engineered as other batteries, so in some situations they will not come out as well and a good premium battery properly spec'ed and used.

BUT in a lot of real situations they will come out ahead of AGM, particularly where the agm is disadvantaged by its situation or has been poorly selected.......which is a large portion of applications AGM is found in.

check the specs and give it some thaught.


cheers

Bantam

I have killed all my battery's, either the Supercharge cranking, and the deep cycle, as an auxillary, or Century cranking, and deep cycle. It does not seem to matter

Best one lasted over 5 years, a Marine Pro deep cycle, in our camper. Always kept charged up. I changed it over, as a matter of precaution, when we did Cape York in 201. It is still going.

Before that trip I did change my main batterys to Century, cranking and deep cycle. The cranking battery died 6-8 months back and I replaced it with a Century 4x4 HD battery, now that is on the way out.

It could be Der Bucky ! What have you done, but I am just looking for a Battery that is not gunna die that quick.

My trips into the Victorian High Country, chasing Bambi is not really over the top, by any stretch of the imagination.

I have yet to find an acid battery that does not eventually leak out, making a bloody big mess, not to mention the damage leaking causes, and my Patrol is a 2001 GU11, no computer, so nothing much to stay on, and drain it overnight.
Kinda makes me wonder if my choices are good or bad.

One thing is that I have yet done is to measure if there are any other power leakages.

In the mean time I borrowed an top of the range battery charger, thinking my"Johnny average" one was not good enough. Not so

Fornthose reasons, listed above I recon it's time to go to AGM

Cheers
Bucky

The first and most important thing to understand is that the design life span of ya standard old technology screw top battery is 2 years.
And with good care an attention and a favorable installation you might ring 5 years out of one.....but I bet ya after 3 it is not working to spec.

With some of the newer technology changes.....changes in composition of the plates, different acid formulations and introduction of glass mats, the normal life expectancy of a battery flooded or AGM can run out to arround 5 years.....treated well ya might ring 7 years out of it but that is pushing your luck.....again I bet ya it wont be to spec after 3 years

Yes in stationary power application it is common to get 10 years out of batteries...but those batteries are treated very well and designed around that expectation.

Those are the realities of battery life...for good quality battereies under good circumstances.

Treated badly and the life of batteries can be dramatically reduced.

THE BIG 3 are
1/Temperature...the better manufacturers publish graps of life expectation V temperature......and the effects are dramatic.

The best life I have had from standard batteries in a vehicle was in my L300 which I ran for about 15 years......I put it down to the battery not being under the bonnet.

2/Cycle depth.....the deeper you cycle a battery the shorter its life will be, AND dramaticly so for many modest batteries one over deep cycle and the battery is shot.

3/Failure to promptly and fully recharge.....Again a dramatic reducer of battery life...........and this one is often combines with cycle depth.

ALL too often people are running batteries that are too small and not having the capacity or giving the time for them to fully recharge.

Combine the 3....and people all too commonly do ...and you have a good quality reputable battery chucking the towel in 6 to 12 months.


Overcharging is less of a problem than it used to be, failure to top up screw top batteries is less of an issue because the sealed batterys are more common and ALL the better quality general use batteries these days are sealed.
And vibration is only an issue for some.


Just facts of life....if you think your problem will be solved by going AGM...you are dreaming.

I've read plenty of posts from people complaining their $400-500 AGM, they where told would solve all their problems did not last as long as the $150 flooded wet cell battery it replaced.

As for the Century batteries...that is one of those brands I have no confidence in and have heard a string of strories about failure in.
The marine pros thoug seem to still have a far reputation.

My recommendation...bang for bucks is good modern sealed marine cranking batteries...or whatever they want to print on the case.

Buy twice as many or replace them twice as often.

cheers

I had a Remco 110 ah agm 2.5 years under the bonnet of my LC100 and then over 5 years in the ute tray/canopy of my Defender. To be fair, the Defender had 170w of solar on the canopy roof and a pretty nifty and expensive controller which I kept a keen eye on. Don't know how long it eventually lasted as I sold the car with solar batt setup with it. Best setup I ever had. Would rarely be down on SOC with alternator and solar to feed it.

Think I'll go marine next - I inherited the current setup and will put up with it for now ;(

If you had not gatherd by my post above.....you can not go far wrong with a good sealed marine battery.
Personally I like the "supercharge seamaster gold", these have a solid rep and a good following in boating circles.

I run them in both cranking and aux positions.

Another battery that has a very good following is the Catipillar "earthmoving battery".....same construction...not sure who makes them for Caripillar, but apparantly they are well priced iff you have a Catipliiar parts depot handy.
Those who are in the eartmoving business, are realy keen on these, because they buy them on the bosses account and get good discounts....( all above board of course).

Ya should get into an N70 sized battery for well under $200 if ya shopping well.


cheers

I like the marine batteries too, but my choice is the Century N70ZM (100Ah) - if you're in Adelaide, you can get them for $153 from this mob (no association, just happy customer)
http://www.batterydiscounters.com.au/marine.html

Wendy-jane and Bantam

Thanks guys
Got me thinking
And that's scarey !

The hydro eye is a rudimentary hydrometer in one of the cells that gives a rough indication of charge......a hell of a lot of batteries have em these days......I don't trust em.....but yeh OK for a quick glance.

I recon they are more valuable for the battery shops....they can tell at a glance that they are giving you a battery that is charged...or they can just look along their shelves and see what they need to give a tickle up.

As for the waranty...don't know.

Another thing about the seamaster gold.....it is a "sealed maintenence free" battery....but once it is out of waranty, ( 2 years from memory) you can peel the top sticker off .....and low and behold the vent valves can be screwed out and the electrolite topped up.......not may sealed batteries you can do that with.

Remember...there is no such thing as a totally sealed battery.....they all can and will vent if over charged or over heated.
Sealed batteries in ..um..."less than luxurious" situations will slowly loose some electrolite over a year or two.
At lease the seamaster you can top up.

As for all those fugure in the tables.
Google em...there are sites that will explain all the standard figures.
Unfortunately not all battery manufacturers will give you a full spread of figures for all battery types.

Mostly automotive batteries you will get RC25..which is how long the battery will run till "flat" at 25 amps, and Cold Cranking Amps....they wont spec AH capacity.

The realy good commercial battery manufacturers will give you full spec and graphs for everthing.


cheers

Wendy-jane and Bantam

Thanks guys
Got me thinking
And that's scarey !

remember..whatever you decide......give it a run and tell us how it all goes.

cheers