Moving forward very very slowly, so I have had a look at the "battery area" in the CAN Gateway of my wife's 2015 VW Polo 6C 1.2TSI 110PS, and found that the original battery is:- Capacity= 59AH, Battery Technology = EFB, Manufacturer = JCB, Serial Number = 111111111 - that must just be default factory settings as it is a 59AH EFB, Exide with a unique serial number.  

So, in the listing for battery technology options in that controller there are:- Fleece, GEL and Binary AGM that roughly cover fitting an AGM battery - so which one to chose as it looks like the three options loosely describe an AGM battery?

At the moment I can't check the BDM subsystem of CAN Gateway in my 2010 Audi S4 as it has a security blocker on the diagnostic port and that can not be removed unless I move the car out of the garage - a job for another day, though I'd think as that is an older car it will have only fields to input the older BEM format of new battery details - time will tell!

1 hour ago, rum4mo said:

 

Go on, explain how that is connected with the comments that I was replying to ie, "Next time I buy a car it will NOT have start/stop and it will not have keyless starting either."

Ah! I was suppose to be answering, "Sounds like you will either be buying a very old car or an EV then, none of this is VAG trying to be clever, it is called progress/emissions reduction". 

I see much of these 'progressive' additions as having 2 goals: to make cars complex (too difficult for servicing outside a dealership with trained techs) and to hike the cost (profit for the manufacturers and garages).

I can see water on a windscreen, so I know when to 'flick' the wipers: I know when I get too close to a car in front and how to apply sufficient braking. None of these 'progressive changes' have any bearing on emissions or economy. Why does the battery need so much electronics? What was wrong with just a simple volt meter and why can't you just change the battery when it dies. It's all unnecessary madness. 

38 minutes ago, rum4mo said:

which one to chose as it looks like the three options loosely describe an AGM battery?

I read somewhere (may of been Ross tech forums) that someone had only ever seen it set to fleece or efb, including on his AGM fitted Audi which was fleece.

16 minutes ago, Confused_Cheese said:

I read somewhere (may of been Ross tech forums) that someone had only ever seen it set to fleece or efb, including on his AGM fitted Audi which was fleece.

 

I did a quick search on that forum, but it was picking up too many threads, maybe I need to refine my search terms. 

 

I did do a general search on Google including "Fleece" and "battery technology" and one return chatted about AGB, and then in brackets Fleece so that ties in, but I wonder why VW Group then included "Gel" and "binary AGM" - that was what confused me slightly.

 

Unfortunately my mate has a 2018 VW T-Roc 1.5TSI 150PS and it has the same EFB battery as the VW Polo 1.2TSI, same or similar for my older daughter's 2019 SEAT Leon Cupra - I think.  I just need to get a look at a VW Group car that is newish and has an AGM battery fitted to stop me digging deeper into this.

 

I might need to look at the Golf forums that that link came from to see if anyone actually reported what they changed their car to when fitting AGM.

Edited 16 February, 20206 yr by rum4mo

51 minutes ago, TerFar said:

Ah! I was suppose to be answering, "Sounds like you will either be buying a very old car or an EV then, none of this is VAG trying to be clever, it is called progress/emissions reduction". 

I see much of these 'progressive' additions as having 2 goals: to make cars complex (too difficult for servicing outside a dealership with trained techs) and to hike the cost (profit for the manufacturers and garages).

I can see water on a windscreen, so I know when to 'flick' the wipers: I know when I get too close to a car in front and how to apply sufficient braking. None of these 'progressive changes' have any bearing on emissions or economy. Why does the battery need so much electronics? What was wrong with just a simple volt meter and why can't you just change the battery when it dies. It's all unnecessary madness. 

 

I should have snipped out the beginning of that quoted posting I suppose.

 

If the motor trade had given EFBs a miss things might have been a bit easier as it seems like very few people are getting reasonable life out of them.

Hmm, well mine is coming up to 5 yrs so not too bad although I occasionally get the message on screen so will have to replace before next winter. Anyway, been rummaging around the'net for prices and found a Yuasa EFB 60 ah s/s for £79 just now so not too bad. Guess Yuasa is not going to sell rubbish, they have a reputation to maintain.

24 minutes ago, Eccles said:

Hmm, well mine is coming up to 5 yrs so not too bad although I occasionally get the message on screen so will have to replace before next winter. Anyway, been rummaging around the'net for prices and found a Yuasa EFB 60 ah s/s for £79 just now so not too bad. Guess Yuasa is not going to sell rubbish, they have a reputation to maintain.

 

I would agree with you about Yuasa, though only based on them being a sponsor of Honda in BTTC, but I'm sure that I've read of many batteries being returned to Halfords due to being basically a bit duff/died/dead, which does not seem right!

 

So, why am I in the business of finding out about swopping to AGM, well, some years ago, I had trouble with a late 2009 Ibiza - battery draining, so as well as buying other new tools, I bought a CTEK battery analyser, and that indicated that the Ibiza battery was well past its best, though not the root cause of the battery draining, eventually that was solved by getting a BCM S/W update.  So, having that battery analyser, I make a point of using it on my batteries annually, this year, for my birthday, I am treating myself to a CTEK charger/support thing, mainly to use when making controller maps of any VW Group cars that come my way. That CTEK charger/support thing arrived and I needed to check that it worked, so I used it to run a charge including recon on my wife's 2015 Polo EFB battery, to be able to evaluate doing this recon, I checked this battery using the CTEK battery analyser and to my annoyance it gave an outcome of "replace battery 500A CCA (EN) - that battery is a 640A CCA (EN) and when I last checked it in late July the outcome was "battery good 600A CCA (EN) - so that drop was a shock, worse was after that recharge+recon it ended up being 475A CCA (EN) and repeating that test a few times over the next few days gives the same 475A CCA (EN) reading - the resolution of the CTEK analyser is 25A so it probably has not changed much before<>after the recon procedure.  There is so far, no other indication that this battery is on the way out, but I'd be a fool if I left it until it let us down.

Edited 16 February, 20206 yr by rum4mo

I have one of these electronic CCA testers and having tested 3 different batteries multiple times before and after charging the results seem very repeatable so whilst I dont neccesarily believe the CCA number it is a good comparator and by recording the results I can see any decline before it causes problems.

 

One thing that I have noticed though, it brings up a warning about switching off all current draining loads, lights, ignition etc before testing, understandable.

 

What I do find though is that the results on the bench after charging even several days after are significantly higher than if the same battery is tested on the vehicle with the battery leads connected even after waiting for the canbus to shut down to sleep mode, I think that the 20ma quiescent current is upsetting the readings or perhaps the high frequency discharges from the tester are waking it up.

 

 

 

@J.R., I can understand that difference I'd think, one thing that I read, I can't say if it is true/obvious or not is, always, just before testing a rested battery, apply a load for a short time then remove it - words like "plate tension" was included in the explanation.

 

Recently, I've always opened the bonnet and waited maybe 30 minutes for the BCM to close things back down, before testing the battery - really desperately searching or removing reasons why I am getting bad results from that Polo battery - in probably slightly in denial, but not enough to turn a blind eye to this issue.  I should order up the diesel engine size battery tray and insulation tomorrow to keep this changing to AGM going as well as getting the next size up battery.

 

Edit:- this "dog with a bone behaviour" will continue I suppose!

Edited 16 February, 20206 yr by rum4mo

I amcurrently your partner in denial 😀

Just now, J.R. said:

I amcurrently your partner in denial 😀

 

I added an edit while you were posting!

7 hours ago, rum4mo said:

 

 I'd be a fool if I left it until it let us down.

For what it's worth I always asked my former (moved now) garage whom I had found to be v. reliable over a number of years to check the battery while the car was in for MOT. I have to presume that he knew more than you or I and he would always give a little detailed report for free.

22 hours ago, rum4mo said:

Recently, I've always opened the bonnet and waited maybe 30 minutes for the BCM to close things back down, before testing the battery - really desperately searching or removing reasons why I am getting bad results from that Polo battery - in probably slightly in denial, but not enough to turn a blind eye to this issue.  I should order up the diesel engine size battery tray and insulation tomorrow to keep this changing to AGM going as well as getting the next size up battery.

@rum4mo
The most likely reason for the poor battery result off the Polo would be due to either a discharge event in the past or something like regular short journey times not allowing a decent recharge to take place before being parked up. The lower state of charge allows the sulphuric acid in the electrolyte to crystallise and harden on the plates inside the battery. This eventually robs the battery of active material and lowers the available cold cranking amps (CCA). There’s no harm discharging a battery so long as it gets recharged to 80% or higher within a few hours of discharging. Leave it discharged a few days and permanent damage results.
 

The reason why you got a higher CCA rating in July over a later reading is probably related to ambient temperature. The warmer the battery, the faster the chemical reactions take place and the better the output. Unfortunately, heat also speeds up the decay of the battery. A good portion of internal decay and damage happens during hot summer periods but it doesn’t show until winter when temperatures drop and the chemical reactions slow leading to a non start event. 
 

The ‘replace battery’ statement comes about due to the difference between measured CCA and voltage. A relatively high voltage and a low CCA rating will trigger ‘replace’ on a test gadget. This is due to loss of active material - damage. The voltage can still be good but the volume of active material inside the battery needed to deliver the amperage to crank the engine has reduced. 

 

The label rating is the approx battery output at -18 deg C. A battery in good condition should show a CCA approx 20% higher than the label rating at room temp. As yours was lower than the label rating in summer, it ain’t far off failure should the ideal conditions align.
 

And finally, the best condition to measure battery output is disconnected from the vehicle (open circuit voltage). This removes any system noise caused by the connected circuit in the vehicle.

Once recharged, leave it for 24 hours for it to soak and stabilise then take a reading. That will be as good as you or anybody else can get. So long as your usage pattern is fairly normal and regular, there will be no harm swapping the current battery out for the same again. Upspeccing to an AGM will help prolong the life of the battery but if you still have a discharge event or constant short engine run times, it will still cause damage and kill off the battery early at some point. Engine run time is key, engine speed has no effect on charging rate. 
 

Hope that has helped clear up a few mysteries!

Nce post BE, actually I knew that engine run time was important rather than speed. Yrs ago when manufacturers were changing over from DC generators to alternators that was one of the advantages they told us we would get. I.e., alternators still charge batteries even on tick over assuming there is no heavy load such as headlamps. With the arrival of LED's, I guess even that will not be much of a problem. Must admit that a lot of my motoring is only 3 - 4 miles and at this time of year, I just take her for a spin for at least 1/2 hour, warms other bits and pieces up for a while too. Because I regard stop start as an ffing nuisance I tend to have it switched off most of the time. I assume that this does no harm??.

Switching off stop start using the dash button does no harm. The charging cycle is still active for the type of battery present. 

@BigEjit, I agree completely with all you have written, so no issue there, the only thing is, this car has over its entire life been "treated with respect" in as much as short journeys don't really feature in its normal life and I tend to keep the Auto Stop/Start disabled unless we are in terrible stop/go traffic.

 

Also this is another thing, that car will still auto Stop after only driving for about a mile even in winter, which sort of is a test of battery health and charge level in itself, I am getting close to carrying out a battery test with the battery disconnected as I agree that must be the ideal test condition.

 

Just to make this even more annoying, I deliberately stopped off at my older daughter's house to stick this CTEK battery analyser on her May 2019 Leon Cupra, which has been sitting unused since a week past Sunday - and the result for it was Battery Good - Recharge  475A, voltage was 12.4volts - it has a Moll EFB 69AH 680A EN battery - now that car prior to being parked had only been used for short runs, but it was a shock to see its CCA testing as 475A exactly the same as the 2015 Polo with its Exide EFB 59AH 640A EN!

 

This has made me suspect my CTEK battery analyser, so I checked the Polo just as soon as we got home ( 30 mile round trip with a stop in the middle) and first reading Replace Battery 500A EN, voltage was 12.7volts, I repeated this test on the Polo 30 minutes later and got Battery Good 525A EN, voltage was 12.6volts - finally I checked an old UPS GEL battery I have to support cars when the main battery is removed and it got the result Replace Battery 100A EN, voltage was 12.2volts - so that one needs recharging. So it looks like this CTEK battery tester can be trusted to give an indication of battery health.

 

It would have been an answer to what I have been seeing if that CTEK battery tester proved to be duff, but so far that does not seem to be the case thankfully.

 

For me this looks like I've just opened a can of worms by checking out my newer CTEK charger/support unit - but there you go!

In my situation, I am almost thinking about buying another battery analyser, but a different slightly cheaper one really to check this CTEK one and see if I can make more sense out of things, I'm a retired test engineer so I can't believe in maybes or grey areas, a bit like a dog with a juicy bone!

 

Edit:- my bigger battery tray and bigger battery insulating cover arrive at my local VW dealer's parts department tomorrow, but I think I'll ride out this winter before actually moving this battery change thing on any more - unless thinks turn bad for me!

Edited 17 February, 20206 yr by rum4mo

The thing is with hand held testers is that they only give a relative indication of output. They cannot be calibrated and are not representative of the testing required to determine actual output. 
 

Midtronics is recognised as probably the best you can get but even those can’t be 100% relied on. 
 

The EN test required to determine true battery output is a week long test of discharging and recharging on a conditioned battery. Everything else is an approximation. 
 

The best indicator of battery health is actuation of Stop Start. If it operates quite frequently, all is well! 
 

If you are storing a battery, keep the voltage as close to 12.72v as possible. Check it once a month and recharge if necessary. Voltage is king, CCA is secondary. Usually a check once every 3 months will be enough if it’s not used at all.

 

A battery in vehicle will vary the voltage according to system demands. 12.5v can be seen on a connected battery whereas it will be 12.8 disconnected. 

Edited 17 February, 20206 yr by BigEjit

This CTEK one is a rebadged Midtronics one it seems.

 

I was/am being lazy with that exUPS GEL battery as I don't need it to be very fit for what I use it for, maybe I'm relying on the fact that in theory these GEL batteries can get left for long periods without losing change - well this one is an "ex" UPS one for a reason, ie its time had come.

 

Yes I understand the actual connected current drain with influence the voltage measured across the terminals, that was what I used years ago on a late 2009 Ibiza that used to drain its battery, checking the voltage with a test lead connected across the battery let me know when the BCM had closed down all the unused power consumers after the car was switched off and locked up.

1 hour ago, BigEjit said:

@rum4mo

 

 

The label rating is the approx battery output at -18 deg C. A battery in good condition should show a CCA approx 20% higher than the label rating at room temp. As yours was lower than the label rating in summer, it ain’t far off failure should the ideal conditions align.
 

 

That makes absolute sense but I think my tester at least gives readings corrected for measuring at 20°c, the readings I have been taking recently were maybe at 10-12°c so will be conservative.

 

I will only know for sure if I test a brand new battery and it does indeed show 20% higher than the rated CCA figure, none of the batteries that I have tested including my 11 month old Varta come anywhere near close.

 

At the end of the day its a comparator but I really need to start off with a good reference point.

 

Mine can measure straight CCA, EN CCA and several others, there is quite a difference in the readings of the first two.

 

I bought it to replace my well served analogue electric toaster one as the scale is so small between an OK and a good battery according to its original capacity that its only really any good to confirm that a battery is dead and also it has to be fully charged to get a meaningfull reading.

 

The new one is great but i really need to get my head around the various test regimes and have a known starting point, I'll keep my eyes open for a brand new car.

As none of these readings are "direct" results, I've always assumed that the CCA was corrected for an ambient of 20C.

 

My CTEK tester came with a "Battery Rating Comparison Table" which gives 5 different measuring standards, namely SAE/CCA, EN, EN2, IEC and DIN. Strange thing is, when comparing EN and DIN on at least my daughter's Moll EFB battery, VW Group seem to be using slightly different values when comparing EN and DIN, which is not too handy.

On 17/02/2020 at 21:16, rum4mo said:

In my situation, I am almost thinking about buying another battery analyser, but a different slightly cheaper one really to check this CTEK one and see if I can make more sense out of things, I'm a retired test engineer so I can't believe in maybes or grey areas, a bit like a dog with a juicy bone!

 

Edit:- my bigger battery tray and bigger battery insulating cover arrive at my local VW dealer's parts department tomorrow, but I think I'll ride out this winter before actually moving this battery change thing on any more - unless thinks turn bad for me!

 

Well an ex-work mate was having problems with his 2017 Audi A6 TDI as its battery was dying, aided by his only using this car now and again, ie once a fortnight roughly, he could not be bothered with the waffle that Audi would feed him even if they agreed to pay for part of the cost of a new battery, so borrowed his preferred local garage's starter pack when it failed to start, and handed in to them to get a replacement fitted.  They ordered up what seemed to be the correct battery which was an AGM one, and the failed battery removed from the car was a same capacity EFB battery which he found strange as he and I always thought all 2017 Audi A6 TDI came with an AGM battery. Anyway as he was concerned about this change of battery technology, and not wanting to offend his handy local garage, I suggested that he visited me and I would check the "battery settings" and change to suit the new Yuasa AGM battery. When I looked in the CAN Gateway channels, there was no option for battery technology, only "capacity" and "manufacturer" and "serial number" - which I found strange as the CAN Gateway in my wife's 2015 VW Polo has "battery technology" and "capacity" and "manufacturer" and "serial number"! So something strange going on there - or maybe the original battery should have been an AGM one - this car was an Approved Used Audi bought from an Audi main dealer in Warrington. 

 

Also, I seem to have regained confidence in my CTEK battery analyser as it measured 875A CCA (EN) when checking that new Yuasa AGM battery which is rated at 850A CCA (EN) - temperature was under 4C - so that means the EFB in my older daughter's May 2019 SEAT Leon Cupra is probably not too healthy for a 10 month old car!

Hey hey, good to hear that that Yuasa sounds quite pukka, what did it cost btw. I cannot quite understand the apparent state of the battery in said Leon Cupra unless perhaps she insults it as my daughter used to do:- When she lived with us she would come home from work park on the drive and leave the headlamps blazing away with the engine switched off whilst phone fiddling for half an hour. When I finally realised what she was doing and did the usual reprimand, "Well it's my car isn't it?" Yes but who will have to come out and rescue you? Which is exactly what happened a few months later when it went flat but of course dear old dad fortunately has jump leads....

That Yuasa AGM cost about £180 all in and that was for a type YBX9019 which is 95AH  and 850A CCA (EN), which sounds like a good deal from a small independent garage. As that car is a 2.0TDI that battery is a monster size wise, but correct for that car.

 

Maybe the EFB should not have been in it in the first place, but - Yuasa claim that that car has that AGM battery from factory, its application list also claims that my wife's 2015 VW Polo 1.2TSI 110PS has an AGM battery from factory, and also that my daughter's 2019 SEAT Leon Cupra has an AGM battery from factory - but I know that the Polo and the Leon both came new with EFB batteries, so sometimes aftermarket battery suppliers get things wrong?

 

Later on last night I sent that daughter a message asking if she had taken up my advice to go for a non stop 10+ miles up and down the bypass while the traffic was light - really to "freshen up" its battery - no reply, I have tried!

Sounds like a good price for an AGM of that capacity, also I very much doubt if VAG would be spending AGM money on an ordinary old Polo certainly my lil ole Fabia doesn't have one, although they may well do so on a Cupra.