Varta LFD90 - Vent or not?

[arthur49]

Maybe I'm being too fastidious ........ but here goes.

 

My two new LFD90s arrived today - great service from Battery Megastore. The box contained some vent tubing. The batteries will be installed under the bunk where I sleep (where current battery is located). One metre behind in same bunk is the Truma heater/boiler, and adjacent to LFD90s is the Sargent EC155.albeit it is in a small wooden ventilated cupboard.

 

I'm grateful to Allan of aandncaravan services for the detail on his website on the LFD90s and Allan sees no need to vent these batteries.

 

And this is where my fastidiousness kicks in. Vent holes are provided so for complete peace of mind should I vent them?

 

The batteries arrived with two transport plugs in the vent holes, one either side, which were immediately removed and batteries put on CTEK charger..

 

If I do decide to vent batteries presumably I put a transport plug back in one vent hole and vent the other one? Or do I vent both sides?

[Robbo]

I vènted my two LFD90's. Just replace the plugs at one end and vent the other end.

 

I used a plastic T adaptor to join the 2 vent tubes together adjacent the batteries and then a single vent tube to the outside world. The adaptor is available from Halfords. Probably a Y adaptor would be best.

 

 

[Brian Kirby]

Is there a risk if you vent them? Is there a risk if you don't? To me, the answer to the first question is no, and to the second possibly, albeit only under exceptional circumstances. Personally, I'd vent.

[aandncaravan]

If you want to vent a LFD90/Bosch L5, remove both transport 'bungs' and just vent one end to a pipe.

Use the 'spare' vent plug that comes as part of the terminal covers to plug the vent hole the other end.

 

Doesn't matter which end you choose to vent to the outside.

 

 

 

[arthur49]

Thank you Robbo, Brian and Allan ...... vent it is ..... :-D :-D :-D

[dipsticks]

Are the LFD90 batteries maintenance free ? I seem to recall reading somewhere that they were. If they are will they still be so when the vents are used I wonder. I'm asking because my existing, coming up 10 years old Varta's, use a lot of water charged by solar.

[Keithl]

dipsticks - 2018-02-07 1:42 PM

 

Are the LFD90 batteries maintenance free ?

 

Yes, Quote from Varta website...

 

" VARTA® Professional Dual Purpose batteries. Long-lasting and maintenance-free, they’re ideal for seasonal use."

 

https://www.varta-automotive.com/en-gb/products/varta-professional-dual-purpose

 

 

dipsticks - 2018-02-07 1:42 PM

 

If they are will they still be so when the vents are used I wonder.

 

Yes, they have a 'Labyrinth' of passages in the construction to recombine any gases. My LFD 90 is now over 6 years old and still going strong with no maintenance.

 

 

dipsticks - 2018-02-07 1:42 PM

 

I'm asking because my existing, coming up 10 years old Varta's, use a lot of water charged by solar.

 

Your ten year old Varta will be an 'old style' lead acid battery and not the 'Powerframe' technology of the LFD 90.

 

Keith.

[Derek Uzzell]

If the ‘coming up to 10 years old’ Varta batteries are using a lot of water, presumably that water-loss is being addressed by the batteries’ electrolyte-level being topped up, meaning that the batteries are ‘maintainable’ and that their cell-caps can be removed.

 

Varta LFD batteries are ‘maintenance free’ in that (short of a surgical operation) adding water to the batteries’ cells is not practicable, and adding a vent-tube will not change that. Varta LFDs are not sealed in the way that gel and AGM batteries are sealed and, if you tilt an LFD battery far enough it will leak electrolyte. But neither of those factors will normally matter.

 

Some batteries are plainly marketed as being 'maintenance free’ but could in fact be ‘maintained’. The showing-its-age starter battery that was removed from my 2009 Skoda car had a large label VERY firmly glued across its upper surface and obscuring the cell-caps. However, scraping off the label meant that the cell-caps could be removed in the time-honoured way. The electrolyte-level was fine, though, so topping the battery up would not have rejuvenated it.

[dipsticks]

Thanks very much for that information Keith and Derek, the two existing batteries I have, are, I believe, Varta Semi-Traction batteries and will be 10 years old in June this year. I have never allowed them to discharge below 12.3 volts and have topped them up 3 times a year. They still seem to work fine and fulfill all my requirements presently, but I am starting to wonder how long can this go on and therefore I avidly read all the useful information I can, relative to getting the best replacements.

 

I have read Allan's recommendations regarding continuous charging, and since I was unaware of that causing more rapid wear, my batteries have been on solar charge constantly for 9 years. I have 125 watts of panel and use an American Morningstar Sunsaver MPPT controller so it would appear that I have been lucky with the longevity of these so far.

 

The only way I have tried to reduce gassing, without a lot of effort, has been to use a simple switch (effectively tells the controller that the battery is gel rather than flooded) to reduce the absorbtion voltage for the charging algorithm from 14.4v to 14.0v when I am not using the van.

 

I'm just wondering now, when these batteries that I have expire, if the LFD9's will be as durable in use if I operate the new ones in the same manner. I must admit it will be great if they do as well, as topping up the existing ones is a tedious job as both front seats need to be removed,

[aandncaravan]

That you are needing to top up the batteries so frequently is a sign that something, like Solar, is overcharging them.

 

 

The Varta LFD Powerframe batteries should be more durable in almost all situations than the old 'Hobby' battery. However, topping up three times a year is a lot of lost fluid, so not sure how the LFD's will adapt to such overcharging?

While we have overcharged them at higher voltages than that for days, not charged them at 14v for months/years.

 

The manufacturer spec specifically states long term float should be at 13.2v - 13.4v.

 

 

Suggest you look at a more suitable regulator that has a 13.2v - 13.4v float voltage or maybe stick with batteries that can have the water replaced?

 

 

 

 

 

 

[dipsticks]

Thank you for that information Allan. I will contact Morningstar and ask them for advice on using my existing regulator for the LFD90 batteries. I would think they will have a good solution as the regulator is easily re-programmed so they should be able to give information in respect of the battery makers recommendations. I hope so anyway, as it was an expensive regulator and has performed perfectly so far. At least they always answer questions and have been helpful in the past.

 

I guess I could also cheat the temperature sensor as Phil (plwsm2000) has suggested, as a resistor and maybe another switch is a lot cheaper than a new regulator whilst the one I have seems to perform so well otherwise.

 

So much praise is heaped on the LFD90's I would like to go for them and it would be a treat to avoid topping up so I will consider the points Allan raised.

 

Grateful for all your help and advice.

[aandncaravan]

We have always said that the Varta LFD/Bosch L Powerframe range of batteries don't lose ANY fluid and are safer inside a motorhome than either Gel or AGM, which contrary to Myth, do lose fluid.

 

We have updated the AGM battery page and added a Tech spec document from Banner for their AGM battery which states the battery does lose fluid >1g/Ah. See : http://www.aandncaravanservices.co.uk/agm-batteries.php

 

So while the Varta LFD/Bosch L ranges are claimed to be absolutely zero fluid loss, the Banner AGM, like all AGM and Gel are low loss, not zero loss.

 

Again confirming that if you think that a Varta needs a vent pipe, an AGM and Gel battery needs one even more so.

 

 

 

 

 

[Derek Uzzell]

Allan

 

if you recheck the Banner technical data sheet for their AGM 59201 battery

 

http://www.aandncaravanservices.co.uk/resources/Banner%20AGM%2059201%20data%20sheet.pdf

 

you’ll find that Banner quotes a water consumption of < 1g/Ah not > 1g/Ah.

 

Less than 1g/AH implies a potential consumption that could be no greater than 0.99g/Ah and might be zero, but it does not indicate that fluid loss will actually occur.

 

Greater than 1g/Ah would indicate that consumption above 1g/Ah will always take place with no limit on the amount of water that would be consumed.

[aandncaravan]

Hello Derek, you are right, I used the wrong symbol, but I disagree on the interpretation.

To me it states there will be fluid loss, if there wasn't any at all it would say zero, just as the Powerframes do..

The battery failure chart below, taken from a 'Lifetime' study of thousands of batteries, shows that 30% of VRLA batteries (Gel and AGM) died from drying out.

That is, they lost so much fluid, the battery was not just degraded, but destroyed.

 

[spospe]

Is the function of a vent pipe on an LFD90 just a safety precaution should the battery start gassing uncontrollably, say at the end of its life when the electrolyte - gas recovery system could become overwhelmed?

[aandncaravan]

Spospe, You could ask exactly the same question about the vent on an AGM and Gel battery?

Which, contrary to popular myth all have vents.

 

AGM and Gel batteries are known as Valve Regulated Lead Acid (VRLA) batteries where the valve controls the regulation of the battery fluid to the outside world.

The valve is designed to open when the pressure inside the battery reaches a set level. They are sometimes incorrectly referred to as 'Sealed' batteries when they are not, the valve is designed to open in normal use.

 

By using this valve to raise the pressure inside the battery, the recombination of the Hydrogen and Oxygen back to Water is more efficient, but not always 100%, hence the loss of some fluid. Especially where the batteries have high current draw devices or fast charging systems, typical in more modern Motorhomes.

 

 

The well documented issue with VRLA batteries is that as a battery deteriorates, creating debris, the valve can become blocked raising pressure beyond safe levels. This accelerates battery degradation, producing more heat and pressure so accelerating degradation still further. This produces still more heat, etc.

Battery explosion is often the end result with this process which is known as 'thermal runaway'.

 

Wet batteries, especially a Powerframe, don't suffer thermal runaway.

 

A Powerframe battery like the Varta LFD/Bosch L series does not gas until exceptional conditions are reached. AGM and Gel batteries will begin gassing at lower temperatures and currents than a Powerframe which has higher temperature and charging tolerances than almost any other Lead technology battery.

 

A battery doesn't gas abnormally at end of Life, that is a condition that only occurs after a battery has been used well beyond exhaustion and into destruction.

 

 

So to address your question, if things become 'abnormal' Powerframe batteries will only start gassing fluid long after Gel and AGM batteries entered meltdown, making them safer in every aspect than Gel or AGM inside the cabin. So if true merit is granted to the Powerframe technology, it doesn't need a vent at any time, certainly less so than Gel or AGM.

 

I ran the same Powerframe battery inside the cabin area of two Citroen Picasso's over a 7 year period without a vent pipe attached. Never once did we ever smell battery gas, which as those who have smelt it is a strong obnoxious substance. This was despite twice leaving the lights on and discharging the battery very low, with a consequential high Alternator charge after jump starting the vehicle.

 

 

It is universally accepted that a Gel and AGM doesn't need a vent to the exterior of the van, yet there seems to be a reluctance to grant the same acceptance to an even safer Powerframe battery because 'it is wet' technology.

 

 

 

[spospe]

You seem to be agreeing with me that a vent tube on an LFD90 is just a safety precaution in case the battery (for whatever reason) should start gassing. i.e. it is there to provide a safe exit route for the battery fumes, should the battery produce any which cannot be contained within the case.

[aandncaravan]

No I am not agreeing. I am saying it is universally regarded that a Gel and AGM don't need them, even under abnormal situations. So if the Varta LFD90 is even safer, and gasses less than Gel/AGM, then it doesn't need an external vent either.

Not even under the extreme conditions that would have an AGM exploding.

 

 

[Derek Uzzell]

This is a peculiar discussion...

 

A Varta LFD90 battery is clearly designed so that a vent-tube can be fittred to it, and in his posting of 14 February 2016 10:12 PM in this 2016 forum thread

 

http://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/BATTERIES/40856/

 

Allan said "We would never say don't fit a vent tube. Fitting one where possible is sensible.”

 

As gel batteries are relatively orientation-tolerant (eg. they can be installed on their side if wished) there’s obviously no vent-tube capability where that type of battery is concerned.

 

Some AGM batteries cannot be fitted with a vent-tube, but some can and, in the latter case, I would have thought Allan’s ‘it’s sensible to fit a tube if possible’ advice would apply.

 

I can’t see what merit there is in endlessly arguing about this. I’d follow Allan’s ‘it’s sensible’ advice, but I couldn’t care less if other people decide to do otherwise.

 

 

[aandncaravan]

Derek, the discussion was about the necessity of a vent pipe in situations where it replaces a Gel battery and an external vent pipe is not available.

 

That is quite different to 'should you use one if available'.

 

It is also about highlighting that Gel and AGM batteries are not the gas free batteries the retailers try and have us believe.

 

[aandncaravan]

Someone is fan of Concorde AGM batteries, or at least they were, until the last two came to a sudden premature end, and sent us the datasheet issued by the manufacturer. It states it's AGM batteries 'need' a charger that is at least 20A per 100Ah battery, otherwise shortened life will result. See chart below.

 

He had fitted 2 x 100Ah's on a Schaudt Elektroblock 18a charger (18a is the absolute peak, but delivers around 16a in most situations) charger, so about 8amps each battery.

We knew about the 'special' voltage but not seen that current requirement for AGM's before, but it does explain a lot.

He was a bit miffed this wasn't pointed out at purchase time.

 

 

But that wasn't the reason for this post, having gone through the manufacturers document he found several warnings on the danger from Gas escape from all VRLA batteries, not just Concorde's own batteries.

 

See the bottom of the AGM battery page : http://www.aandncaravanservices.co.uk/agm-batteries.php for more detail and the full document..

 

 

One other myth that is exploded, mentioned above, in the document is that Gel batteries can be mounted in any position.

Concorde, the largest AGM manufacturer for Commercial and military batteries so clearly a class act, say that the operation of Gels on their side can lead to burnt plates and battery damage. All Gel batteries must be operated on their base but most AGM's can be operated on their side, and even inverted for short periods.

 

I can't add the chart, need to edit it so it is smaller before I cam attach it, will do that tomorrow.

 

 

 

 

 

[aandncaravan]

Here is the text saying a 20amp AGM charger per 100Ah battery is a must to preserve battery lifetime, plus their voltage versus temperature chart.

 

 

 

Note on the chart how the Float voltage at a Summers day temperature is advised at 13.39v but that during freezing Winter temperatures a Float of 14v is acceptable.

 

That maybe suggests, that for this particular battery range, being on long term EHU at 13.8v Float where half of that time is during a cold Winter, might actually be less damaging than Float charging with 13.8v Solar in Summer?