BUGGER Battery Isues

Trusting a 3 - 4 year old battery is as smart as trusting an old bloke of 66 going on 67. As my wife will assure you - don't!

Max

Thanks Mainey,

I now have two 100 amp AGM deep cycle so have 200 amp hours and will hook up in parallel as for the 6 mm cable don't know (auto electrician did it) so am going to pull it out and run battery cable from my main battery to the new batteries in the ute tray.

All others I have seen the cables are somewhat larger than the ones put in for me. The person I'm getting the batteries off indicated the cables are bit small and they should be battery cables.

So more work I did not need at the moment :).

Brian

col,
without suggesting things are not as they would appear...

Considering the thought that a 12v Deep Cycle battery should be receiving about 14.4 Volts and also receiving sufficient Amps from an Alternator that's rated @ 50 (plus) Amps. . .

I often wonder why a Deep Cycle battery won't become fully charged?

After all, the 240v battery charger will charge @ about 14.4 Volts and usually less than 10 Amps.

Mainey . . .

The Alternator only produces 14.4V until the motor starts to warm up. When the warm up commences the temperature regulation in the alternator will start to drop the output voltage and when the motor is warmed up the output will be in the range of 13.4 to 14.0 V. You will only get the high current that Mainey is suggesting for a few minutes - the rest of the time the battery will only be receiving the same voltage from the alternator as a multistage charger supplies when it has switched to folat. This is explained in http://www.ranox.com.au/452.html His voltages may be a little different to my experience but that is just nit picking, the theory still holds up.

If you wish to charge your batteries fully you can do no better than installing this battery booster. The booster is fully adjustable, you can set the charge and float voltages in 0.1 V steps and the output current between 5 & 25 A in 1 A steps. You are able to tailor the output to suit any type of 12 V battery. The latest model is fitted with input voltge sensing so that you do not need an external battery isolator with it.

PeterD

An AGM Deepcycle battery will charge fully off 13.8 volts - I do it all the time.

Col,
Derek Bester, from ABR, who has an extensive technical and mechanical background wrote the following on the EO battery information page.
Link ->Charging Deep Cycle battery

""Recharging
When a battery recharges, the charge is not consistent - as a guide it will bulk charge until about 60 - 80% full and then slow down and the *BALANCE* of the charge may take as long as the first 80%.
In the example above, the 60 amp hours used will take roughly 2 hours to *FULLY RECOVER* on a 100 amp alternator, lets say 45 amps in the first hour and 15 amps in the next.""

In simplistic terms it does state the Deep Cycle battery will be "bulk charged" till approximately 70% charged, then the balance (as in the rest of the charge) will be charged at a reduced rate, till the Deep Cycle battery *fully recovers* (from it's discharged state) in just two hours.


Now maybe we can forget the 'stories' often printed that a vehicle Alternator will not fully charge a Deep Cycle battery, because Derek has actually shown by clear example how it is so easily achieved !!

Mainey . . .

Mainey, you may call them stories but facts are facts, its not the alt that prevents full charging but the regulator, these facts also apply to lead acid batteries. You state facts from Derek Bester, i also can put names forward try Collyn Rivers his credentials are electrical engineer. As i stated before even battery manufactures state that you cannot charge a battery to 100% of capacity. You are partly right how the charge rate works, once the regulator tapers off it comes down to a trickle and will take many hours of constant charging to gain a few more % above the 70 to 80 % already charged. Another respected electrical namei is John Payne and is into marine electrics and electronics, and he also states that10% of nominal battery capacity is not uncommon. A simple test is after a long period of non stop driving put a 240 volt smart charger on the battery and see how much more power it will take and how much longer you can run your fridge of that battery. I have done this using a christy generator which has a modified regulator and have found i have more usable power than what the car alt can supply. I also would not take all the facts a 12 volt auto electrician tells me as after speaking to many sparkys around oz have not got one consistant story about some of the issues on this matter. Col

Derek Bester is not an electrical engineer versed in deep cycle battery theory, if he was he would have designed his own battery booster and would not have been involved in selling battery isolators.

I agree with Col, most auto electricians do not know much about deep cycle battery theory. They will mostly tell you that alternators do not have temperature compensation in their regulators. If they knew that then they would realise the futility of attempting to charge batteries that are not under the bonnet from the alternator.

PeterD

Sorry guys,
I believe I have very clearly indicated I did "copy" the 12v battery charging article By Derek Bester, as is shown on ABR's "Battery Power" article on our Exploroz battery power information website, which was updated on 10 June 2008 and I even posted the link direct to the article.

Therefore, obviously they are not my words at all, they are Derek's

So if you guys *don't* agree with Derek's 12v battery charging information and therefore believe it's wrong ??

( Col, as can be clearly seen I used the word 'stories' in jest )

Mainey . . .

Hi mainey, yes i understand you did copy some one else's theorys, but its my understanding from what you have posted on this thread and past threads, that you understand iwhat you read is actually fact and try to push that point without understanding or having the knowledge to have a knowledgeable opionion based on your own experiences. I have to say also that it was not clear that the word stories was used in jest, because ( dereck ) said so. I find it quite amussing that you have a photo of an electrical set up that shows absolutly nothing or any use to any body. I my self, based on past experiences would not use any of your ideas to power my 4by4 or camper trailer, as i feel you havent the facts to back up your theorys. ( only jesting ) ha ha Col

Hi mainey, also should have said by looking at your profile you have put in wiring in your electrical system based on the outside diameter of the cables run of the battery, you should be looking at the copper diameter of the cable, ie 6mm minium internal measurement for cable run from battery to fridge in back of wagon, with a maxium of 6 metres before you start having a wastefull amount of amps that affects the battery life before the need for recharging. These are all the little things that pro long the efficiency of what ever sort of battery fitted to your system. ( just Jesting ) When i get the chance i will put a photo o f my set up, all manual no soliniods or electronics, running fridge, whinch,lights and big sterio to annoy the neighbours. (Just Jesting ) Col

Its a misconception that a car alternator will not fully charge any sort of battery. It will charge the battery fully provided the alternator is putting out the correct voltage for the battery type, and you drive long enough.

Its a misconception that the Alternator regulator reads and governs the amps that go into the battery. An alternator puts out a fixed, temperature compensated voltage, with current limiting well above the battery's maximum absorption current. There is NO current sensor in the battery lead. (There may be 1 or 2 exceptions this)

Col
Hi,
I’ve looked everywhere on this website for the “photo” you have mentioned above :-> ““you have a photo of an electrical set up that shows absolutely nothing or any use to any body””

Col, will you please post the link to the “photo of an electrical set-up” you are actually referring to and yes I will clarify each and every question you have about it !
Unless of course you are only referring to the various individual pictures of the two Solar panels, Solar Regulator, three batteries, Inverter and various gauges I've installed to monitor the complete 12v power supply and distribution system.

Col, I have NEVER ever stated the “outside diameter of the cable” of my system at any time, I always state the Battery cable I use is “2 B&S” which is as my profile states “those AGM battery cables are thick (32 mm²)” and yes, it refers to the size of the actual copper cable and not the “outside” protective covering.

My power cable from the AGM battery system to fridge is about 2.8 Meter long and its 10 mm² (thick), and does give ‘zero’ Voltage drop, which is far more efficient than using the very much thinner 6mm² you mention.

Mainey . . .

Hi Mainey, when you send a follow up or a post there is always a photo of a battery with cables coming of the terminals, it was my assumption that is the set up in your vehicle, if this is not the case my apologies. Col

Hi Mike, i agree with what you say in that the alt puts out the volts and amps but its my understanding that the regulator reads and governs what goes into the battery, thats why there are so many sorts of regulators, such as what is put on a christy generator, it has a 2 way manual switch where you can govern what you put into the battery, the LED screen shows this instantly as does a multy meter wrapped around the cables. Another sort of regulator is hard to find in oz, and no good for a computerised car is a 3 stage unit which does extactly the same as a 240 volt smart charger with a pulsator to revive and stop sulphation on the battery plates, i am in the process of getting one of yhese units as they will put into the battery more than a standard regulated alt. As i have said in previous post even the battery manufactures state you can not fully charge a battery, the only units that will come close are smart chargers and regulated solar panels. I would be interested to hear how power is managed from the alt to the batt, from your point of veiw. Col

kiwicol posted:

" its my understanding that the regulator reads and governs what goes into the battery,"
- the Alternator output connects directly to all car electrical loads AND the battery. The regulator can't tell whether the 50 amps it's delivering is going to the battery or the car electrical loads.


"As i have said in previous post even the battery manufactures state you can not fully charge a battery."
- If you look at the manufacturers data sheets for AGM batteries, you will see that they will charge fully at voltages as low as 13.8 volts.

Sorry mike but the regulator only reads what the battery needs thats why if you remove the battery with all the electrical loads working you will do severe damage to the alt, but that may only be to the regulator, not quite sure. And yes it is the regulaor that governs the power, even when the regulator is at low out put the alt is giving out what ever it is rated at you cant change that. I am curious to understand how you see the alt stopping out put when you say the battery is full, otherwise i see you overcharging the battery. I see it as the same principle as a A/C compressor with the clutch doing as the regulator does, the only difference being the compressor stops when the clutch dissengaged. As for a fully caharged battery talk to an electrical engineer, not a automotive sparky you will find you get completly different answers, as its my understanding fully charged is complety different to charging rates. You will have to dig deeper than a manufactures home page to get the facts on what a product will do. Also you say 13.8 volts is low, you will find most 12 volt systems only put out at max about 14.2 volts and then the regulator kicks in and the volts go down to what the battery needs. Col

"Sorry mike but the regulator only reads what the battery needs thats why if you remove the battery with all the electrical loads working you will do severe damage to the alt, but that may only be to the regulator, not quite sure. "
- No, the reason for the damage is the "load dump" voltage surge that occurs when you suddenly disconnect the load from a current-carrying conductor (the stator coil).

"I am curious to understand how you see the alt stopping out put when you say the battery is full, "
- A lead-acid battery is self-regulating - when you apply 13.8 volts to it, it will automatically reduce the current it _Affordable_Storage_Drawers.aspx, as its state of charge increases.


"As for a fully charged battery talk to an electrical engineer"
- I have Honours Degree in Electrical Engineering and I've been designing building and testing electrical and electronic equipment for forty years.

"you will find most 12 volt systems only put out at max about 14.2 volts and then the regulator kicks in and the volts go down to what the battery needs. "
That's the temperature compensation dropping the voltage. It's a feedforward system where an ouput is provided which will do the job in normal conditions, but there is no measurement of effect (battery current) to see how well it's charging the battery.


Col

Col,
You posted:
""I find it quite amussing that you have a photo of an electrical set up that shows absolutly nothing or any use to any body...... there is always a photo of a BATTERY with cables coming of the terminals, it was my assumption that is the set up in your vehicle""

It's good to read your "amused", even if it's simply by a picture of an AGM battery with it's attached 32 mm² battery cables.

Yes, the "electrical set up" is (was) a picture of one of the two identical 100+ ah AGM Deep Cycle First Power batteries !


However have now changed it, hope the new picture meets with your approval ha ha

New picture is now my slide on/off 200+ Watt Solar System.

When you click on the picture you can clearly see the stainless steel 'ny-lock' locking system holding the rear panel securely in place, it just slides out when required to be put out in the sun, when I camp under the trees for shade, it's connected by a 10 Metre extension cable to the Battery system, via the solar regulator, hope it 'amuses' you just as much as the battery picture did, LOL.

Mainey . . .

Hi Mike, i am having problems here as all the material i am reading from electrical engineers are all stating that its the regulator that governs the out put to the battery either from within the alternator or across the battery, knowing the system should be operating at between 14.2-14.4 volts the reg adjusts the output voltage by switching of its field at very high speed and this appears in the system as constant voltage. In your view can you explain what the regulator is actually used for if not for my above believe. Col

Col

In Followup 7 above, I wrote "An alternator puts out a fixed, temperature compensated voltage," - that's what the temeprature-compensated regulator does. When the Alternator is cold, it puts out 14.2 volts to quickly replace the charge used in starting. When the Alternator warms up due to taking in air off the radiator, it drops its voltage to around 13.8 - the 3rd stage or float-charge voltage that any 3-stage charger puts out. This will charge the battery slowly without overcharging it, as the battery self-regulates how much current it _Affordable_Storage_Drawers.aspx - it stops drawing current when full.

During stage 1, a 3-stage charger limits the current to the battery to prevent damage. An Alternator can't limit battery current because it doesn't sense how much of its output current goes to the battery and how much to the loads.

During Stage 2, a 3-stage charger puts out a constant voltage around 14.2v - as does a cold Alternator.

A 3-stage charger drops to the Float Voltage (Stage 3) when it senses that the battery current has dropped to 1/40 C. An Alternator can't sense battery current, so it progressively drops to the Float Voltage as the Alternator warms up. This timing is designed to suit typical driving conditions where less than 1% of battery capacity is used to start the engine.

If you have heavily discharged the battery and only drive for half an hour, the battery will not recharge fully. But if you are a typical traveller and have used 50% of charge to run a fridge, then after 4 hours driving the battery will be close to full. If you have a wetcell deep cycle you will have to drive for a lot longer.

Mike now i am confused, are we talking about a standard regulator standard on on 99.99% of vehicles, or the 3 stage unit as they are as stated by your last post completely different. So how does a battery self regulate when it has no moving or mechanical parts, and by what you are saying you cannot over charge a battery as it will deny the input. When you say after 4 hrs travelling the battery will be close to full is that the total capcity the battery can take or is it the max the alt and reg can put into the battery, as its my understanding that they are 2 different issues. Yes heat is a factor and thats why the reserve capacity is the scale to use when buying a battery for your set up as all the other scales are heat affected. I would also like your opinion on the christy generator which puts out more volts and amps than the standard vehicle alt, by using a manual switch to change the out put of the regulator, as stated by the manufacturer. I have to totally disagree about what the alt reads, it only reads the battery not the power consumption being put to the battery, once the battery gets below a certain point the regualtor will then kick in and supply the battery with more amps, when just suppling a fridge only a trickle is needed, but put a whinch into the equation working at full power the regulator will put every thing the alt has to offer, and this is why 24 volts is a better system for 4by4 whinch challenge compitions. Col

It seems I'm wasting my time explaining in extensive detail. Everyone else can understand this type of explanation.

I give up.

Hey Mike, yeah probably is a waste of your time :-) :-)

Mainey . . .

Hi
I think there is aliitle cross confusion
1ST:- Col,you are partly correct the regulator has to adjust for a wide range of revs.
An alternator output encreases as revs encrease to control this to the required voltage the field current is regulated by switching or controlilng it .
2;-What Mike is saying is that the regulator CANNOT CONTOL CURRENT IS CORRECT . it contols voltage.
3:-The current that goes into the battery is dependent on the differance between the battery voltage,say 12 v for LOW BAT & the alternator controlled output volts 14.2 v THIS WILL GIVE A HIGH CURRENT which will taper off as the battery volts approaches the alt output volts & as Mike has said the alternator will bring in a temperature compensated voltage of around 13.8v .
4:- When the battery voltage reachs the alternator output volts their will be no potential differance between the two & the battery will cease to be charged

Hi all \, i agree to disagree and will keep on my path to get a 3 stage regulator to fit to my alt to give me more power and battery maintenance than the standard regulator. I also will keep my belief from the literature from many authors that i have read and the auto sparkys that i have dealt with to be fact. AS for the statement that a battery will stop accepting a charge when full, how many times have i heard or seen a battery destroyed by over charging, from poor regulating of the input and the heat then destroys the battery. Col

"AS for the statement that a battery will stop accepting a charge when full, how many times have i heard or seen a battery destroyed by over charging, from poor regulating of the input and the heat then destroys the battery. "

If you don't understand the importance of having the correct charging voltage on a battery, then no wonder it's been such a hard slog.

Mike it hasnt been a hard slog as i do understand the basics, i get a minimum of 3 years from my lead acid batterys, made in australia, having stayed with the same brand, size and age per 2 set and have never been let down. This undersatnding has worked for me for the last 20 yrs of camping 4by4, sometimes as my last trip was for 10 mths living and serving of my batterys and a christy gen set. I do not run and electronic or solinoid units between my batterys and have survived entirely of my basic knowledge of what my alt (55 amps ) and my batterys and my usage dictate how when and how much i should charge my batterys. Once again i will state its the regulator on the alt that dictates what power you can use out of the battery with out destroying the battery, being a lead acid or deep cycle. I will agree to disagree. But also enjoy the input and time put in by yourself and others as hopefully others have picked up pointers from all sides. Col

Hi,

Yeah I have the same a simple solonoid and has worked for 3 years happy so far.

I would however like a gauge in the cabin to show me what charge is in the dual batteries so if a problem happens I can act before I find the beer warm. Considering also a gauge in a cabin to show what temp the fridge is at.

Just like everything more pressing matters arise and the above plans go down the list a bit.

Brian

Same system was in previous van and 4wd and it worked 100 % for 5 years.