1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Battery help

Discussion in ''How To' & 'Handy Hints'' started by Josht3, Jul 9, 2019.

  1. Josht3

    Josht3 New Member

    Messages:
    24
    Location:
    Perth, WA
    9D0B9B3A-554A-4DE7-823B-38BBC7A5E713.jpeg 4B035D18-39E5-4EBA-9546-AA8927E8247D.jpeg Hey guys! So I’m new to this camping and battery thing but I was wondering if someone savvy could help me out.

    I have a mate of a mate who’s selling second hand deep cycle batteries, he has two types and I’m not sure which one I should be choosing, he recommended the 75ah over the 100ah one as the 75ah amg would be more suitable for camping and the 100ah more suitable for 4WD’s and should be charged through a dc charger and not through an alternator or something like that, although he’s not too battery savvy either, that’s just what he’s been told. I have taken them both to battery world to have them checked and they are in great condition, but he wasn’t too keen to give me advice as I wasn’t buying one. I have to drop one or the other back tonight and I’m not too sure which one!

    I’ve attached photos, please help!

    Thanks
     
  2. Mr Beckstar

    Mr Beckstar Well-Known Member

    Messages:
    1,021
    Location:
    Bateau Bay, NSW
    @Josht3, do you still need information about this or is it sorted?
     
  3. AC-T3

    AC-T3 Well-Known Member

    Messages:
    961
    Location:
    Woy Woy
    Sort of sad. If only the facts could be resurrected, you know, like the atmospheric % dilution ratios and such like that make the difference between a safe and unsafe installation. Think I remember most of the details posted by various.
     
    Mr Beckstar and Grantus like this.
  4. drivesafe

    drivesafe Active Member

    Messages:
    145
    Hi Rob, here is a reduced version of my post on gas ratios and safe battery locations.


    Under NORMAL use, neither Wet Cell or AGM batteries gas, especially when being charged by an alternator. Furthermore, the voltages required to cause excessive gassing in either type of battery is higher than most alternators operate at.

    Also, the voltages required to cause a Wet Cell battery to gas excessively are actually slightly higher than the voltages that will cause most AGMs to start releasing excess gas.

    The most common cause of batteries gassing is when charging with a battery charger.

    Next, most people think that a battery will produce unlimited amounts of hydrogen if over charged.

    This is not correct. All batteries have set limited amount of hydrogen they can produce, based on the Ah size of the battery.

    There are sets calculations you can use to determine the minimum area surrounding a battery, above which the battery will not need to be vented.

    Now, for hydrogen to become dangerous, it must reach a hydrogen to atmosphere ration of 4.1%, The international maximum safe level set for hydrogen is a ratio of 2% hydrogen to atmosphere.

    A good few years back, I used these calculations, based on the interior cubic area of my Range Rover Vogue, and calculated that I could fit three 100Ah batteries in the rear of my RR and if all three were caused to totally gas out, releasing all the hydrogen available, the ratio of hydrogen to atmosphere would not reach 2%, let alone get to the explosive level of 4.1%.

    A rough guess is, as the cubic area inside a Kombi is a bit less than double that of my RR, you could safely fit four 100Ah batteries and they could not produce enough hydrogen reach the ratio of hydrogen to atmosphere of 2%.

    The exact reverse is the case when you mount a battery in any form of enclosure.

    The potential of a battery exploding and the additional damage caused when fitting a battery in an enclosure, can easily be one hundred times greater than if you simply mounted the battery in an open area, like a Kombi engine bay or in the cab.

    THIS APPLIES EVEN WHEN THE ENCLOSURE IS VENTED.

    When a battery is caused to gas, if the battery is in an open area, the gas being released, mixes with the surrounding atmosphere and the ratio of hydrogen to atmosphere reduces very quickly.and the hydrogen content of the atmosphere will become so low that the mix, just a short distance from the battery, is no longer dangerous.

    When a battery is placed in an enclosure, and gasses, because there is a limited amount of atmosphere surrounding the battery, the ratio of hydrogen to atmosphere quickly reaches and stays at a dangerous level while ever the battery is gassing.

    With a battery in the open, the only place the hydrogen will be able to get to dangerous ratios, is in the battery itself, and with a 100Ah Wet cell battery, the amount of area inside the battery, in the top of the battery, is between 200 and 400 cubic centimetres, depending on how much water is left in the battery.

    Using the dimensions of the average 100Ah battery and placing it in an enclosure that has no more than a 2cm clearance all round, you will have a cubic atmosphere area of almost 6.000 cubic centimetres, able to accumulate a hydrogen enriched atmosphere.

    The problem gets worse. Most people will not make a battery compartment for their auxiliary battery. They simply mount the battery in a spare cupboard, which will have many times the available space around the battery for the hydrogen to accumulate in.

    And it gets even worse. As above, venting the battery compartment does not make the battery safe, venting can help to reduce the amount of hydrogen that will be retained in the enclosure, while the battery is gassing and once the battery the battery has stopped gassing, the venting will HOPEFULLY, eventually allow any hydrogen buildup to escape.

    But there is still another problem. Most people have absolutely no idea how to set up correct venting.

    To set venting up so that it gives you the best possible results, you need a minimum of two vents. One located at as low a position on one side of the enclosure and a second vent must be positioned as high as possible on the opposite side of the enclosure.

    This is the minimum type of venting setup but note, you must not put the vent on the high side, in the roof of the enclosure, as this could be accidentally cover.

    This whole fiasco about putting a battery in a vented compartment comes from people not understanding what is required to making a battery as safe as possible.

    When someone states a battery must be in a vented compartment, they actually have the cart before the horse.

    The full and correct statement would be “If you have no other choice but to put a battery in an enclosure, then that enclosure must be vented” Using a battery enclosure is the LAST choice, not a mandatory requirement.

    I hope this helps to make battery use somewhat safer for those planning on adding a second battery to their Kombi.
     
    AC-T3 and Grantus like this.
  5. Mr Beckstar

    Mr Beckstar Well-Known Member

    Messages:
    1,021
    Location:
    Bateau Bay, NSW
    @drivesafe how/where are your batteries mounted in your Kombi? Do you have the AGM or the Wet Cell? What’s your amp-hour rating? Are you using a deep cycle battery or not? You’ve explained all the “don’ts” above but, personally, I’d find it much easier to relate to the actual installation you’ve got, which I’m sure would be well designed.
     
    David H, tintop and Grantus like this.
  6. syncro

    syncro Well-Known Member

    Messages:
    9,325
    Location:
    Southern Highlands
    I have my battery in the factory location under the driver's seat. I have my auxiliary battery in the factory location under the passenger's seat.
     
    old grey and Luckyphil like this.
  7. Luckyphil

    Luckyphil Well-Known Member

    Messages:
    5,991
    Location:
    Gosford
    Hydrogen produced underneath & methane above :)
     
  8. rstucke

    rstucke Well-Known Member

    Messages:
    1,015
    Location:
    Wamberal NSW AUS
    Read this from Century
     

    Attached Files:

    Last edited: Aug 13, 2019
  9. rstucke

    rstucke Well-Known Member

    Messages:
    1,015
    Location:
    Wamberal NSW AUS
  10. tintop

    tintop Well-Known Member

    Messages:
    502
    Location:
    Canberra
    thanks rstucke, that info is in line with my expectations of the AGM VRLA batteries in my Kombi and Sprinter
     
    Mr Beckstar and rstucke like this.
  11. rstucke

    rstucke Well-Known Member

    Messages:
    1,015
    Location:
    Wamberal NSW AUS
    That's how I see it as well
     
    Mr Beckstar likes this.
  12. syncro

    syncro Well-Known Member

    Messages:
    9,325
    Location:
    Southern Highlands
    What would be the result of these "explosions"?
     
    Mr Beckstar likes this.
  13. rstucke

    rstucke Well-Known Member

    Messages:
    1,015
    Location:
    Wamberal NSW AUS
    You might want to research that yourself, I've got a couple of horror stories that I was witness to.
     
    Mr Beckstar likes this.
  14. rstucke

    rstucke Well-Known Member

    Messages:
    1,015
    Location:
    Wamberal NSW AUS
    @drivesafe, we got off on the wrong foot
    please add your opinions and info ( in a civil way)
    There are people here that want your thoughts and value them.
     
  15. chris taylor

    chris taylor Well-Known Member

    Messages:
    1,900
    Location:
    adelaide sth aust
    Agreed rstucke,All info is valuable.
     
    Mr Beckstar likes this.
  16. syncro

    syncro Well-Known Member

    Messages:
    9,325
    Location:
    Southern Highlands
    Was it an over pressure failure or combustion? A lot of stuff on the internet is BS. Now what is your witness experience?
     
    Mr Beckstar likes this.
  17. AC-T3

    AC-T3 Well-Known Member

    Messages:
    961
    Location:
    Woy Woy
    Thanks @drivesafe and @rstucke for re-posting. Feeling happy with the 2 batteries in factory designed compartments in my T3. Just as VW would have designed it, I'm sure.
     
    Mr Beckstar and syncro like this.
  18. drivesafe

    drivesafe Active Member

    Messages:
    145
    I have an 55Ah Optima D34 Yellowtop as my auxiliary batter, mounted in the back of my 2017 Tiguan.

    Because of the Tiguans 140 amp alternator and it 14.7v ( recharge ) operating voltage, I take full advantage of the Optima’s fast charging capability

    A Kombi, with its much smaller capacity alternator, 55 amp standard or 75 amp upgraded, and a constant operating voltage of around 14.3v, will not gain any real advantage from using a high performance Optima as its auxiliary battery.

    A standard Wet Cell or AGM battery will be fine and it can be a deep cycle or cranking battery, located in the engine bay, opposite the cranking battery, would be the optimum setup.

    With the auxiliary battery safely mounted in the engine bay, you are not wasting any cabin space, plus with the auxiliary battery located close to the cranking battery, because the cable run is short, you reduce the voltage drop, allowing to auxiliary battery to charge just that bit quicker.

    As to the size of the auxiliary battery. his is completely up to space available and both how long you want to free camp and how many items you want to power from the auxiliary battery while free camping.

    Hi rstucke, and while it has nothing to do with you but that first document is not all that relevant to what the OP is intending.

    It sort of covers the potential of cranking battery explosions while starting or using a vehicle, which are is a small portion of the types of explosions in the RV industry, and it doesn’t cover the greater potential of how battery chargers can cause batteries to explode.

    Then on the next page it goes on about what size charger to use on their batteries. Note, this is not about charging batteries intended use cranking use. This is about charging batteries for cyclic use. Batteries that are used in golf carts or electric forklifts by day and may need to be recharged from flat to a fully charged state overnight.

    The 10 to 15 amp charger is a commonly suggested by most battery manufacturers, to make sure their batteries are well maintained in this type of operation, without the need of using higher current chargers, which in these types of continual use, will shorten a battery’s operating life span.

    I also noticed that they state that AGMs have a lower chance of being cause to explode, not that they are safer, and even this too was only applying to while the battery was being used as a cranking battery. No mention of what sort of danger charing with a battery charger could impost on any type of battery.
     
    Mr Beckstar and rstucke like this.
  19. Maccas

    Maccas Member

    Messages:
    52
    Location:
    Gosford
    Thanks drivesafe for your words of wisdom, experience & caution, your pertinent words for my 1990 T3 TRAKKA camper conversion reproduced above.

    It's an interesting conundrum then for me.

    T3 TRAKKA camper conversions such as mine include a wooden box enclosure with lid that allows a close fitting maximum 100 AH camping battery, located under the enclosed rear rock & roll seat. It has no "venting" provision as such, it does have a single corner cutout at the top of one end, enough to feed all electric cables through into the box. A clip down wooden flat lid sits on the top of the box. The long sides of the battery is a snug fit in the box, the short sides, there is 1 cm gap at each end. I've always fitted packing spacers in those gaps to prevent movement. There's 3.5 cm space at the top of the box above the battery, needed space to run all the cables to the battery poles.
    So I've concluded, taking into account your advice, then ALL aspects of the TRAKKA camping battery install does not represent safe battery practice.

    So when it comes to my van though, on the one hand, taking into account all stated above about what NOT to do when designing space for a camping battery, seems to me then that TRAKKA at least as far back as the 1980s with its design team, has blissfully ignored all that good advice right through to the end of the VW T3 model in 1992, and perhaps blissfully continuing on into the T4 model as well.

    Yet on the other hand, some 30 or more years later with at least 4 owners of my van in differing conditions, perhaps all ignorant about best battery practice, ranging over wet cell full maintenance batteries in the 1980-1990s, venting low maintenance type later on, through to fully sealed no maintenance batteries currently, the thing for me is, despite all the van has been exposed to, it's still alive and well, no battery explosion nor fire damage. Only physical damage I can see is six acid damage circles showing on the underside of the battery box lid, obviously due to venting from the battery caps, probably during the time of a 1990 circa owner.

    Beats me. Put it down to pure luck of at least 4 owners over 29 years and 230,000 klms?
    Think I'll keep my fingers crossed!
    Cheers.
     
    Mr Beckstar likes this.
  20. rstucke

    rstucke Well-Known Member

    Messages:
    1,015
    Location:
    Wamberal NSW AUS
    I wouldn't keep my fingers crossed.
    Either remove the enclosure or vent it properly
    It's a disaster waiting to happen especially if you are charging it externally or have bad connections
     
    Mr Beckstar, drivesafe and Grantus like this.

Share This Page