11 minutes ago, xman said:

Imo it was NOT a hydrogen explosion.

 

No it was indeed an internal source. 

Edited 5 April, 20206 yr by digifish

11 minutes ago, digifish said:

And here is the outtake

 

https://www.youtube.com/watch?v=BGilVlhzACY

 

 

 

 

Was that an explosion? 💥It looks as if you have a 300amp battery charger judging from those connector leads.

😁

Edited 5 April, 20206 yr by xman

3 minutes ago, xman said:

Was that an explosion? 💥It looks as if you have a 300amp battery charger judging from those connector leads.

😁

 

They're connected to an Arc Welder, it charges quicker

 

Pro tip. 

 

I’ve finally managed to connect my charger to the Superb. After a few hours I’m at stage 4, absorption. As battery is EFB I've used the normal program. Couldn’t resist checking voltage; meter reads 14.6V, manual states 14.4V. 
I wonder if this is the temperature compensation feature coming into play or whether my unit is slightly out of spec? Ambient temp here is 13 deg C. 
Does this sound about right to those in the know?

 

Edited 6 April, 20206 yr by Howardd

Every thing is fine. Temp compensation, if your unit has it would be good, better if it actualy takes battery temperature.

 

Standard figures are usually quoted at 20-25 deg C. Charging voltages ideally decrease with increasing temperature, approx -0.025V per deg C, so 14.6v would be correct for ambient of around 12-17 deg C.

Again, many thanks XMan for providing this useful info. I now know that my charger is almost certainly performing to spec. 
The CTEK manual states that temp. compensation is incorporated in the unit but, unfortunately, goes into no further details. 
 

I don't see how the charger can tell what the ambient temperature is when it generates so much heat itself so I would probably bet that they don't have temperature compensation.

1 hour ago, SuperbTWM said:

I don't see how the charger can tell what the ambient temperature is when it generates so much heat itself so I would probably bet that they don't have temperature compensation.

 

Ctek mxs 5.0 has temperature compensation.

 

 

Just a guess but temperature might be sampled before bulk charging commences, and when charging current has dropped sufficiently during the absorbtion and subsequent phases.

Edited 7 April, 20206 yr by xman

@xman I still can't see it working very well, those chargers are a very dense brick, what if you have been using the charger previously and its already hot?

 

As you've said, you really need to know the temperature of the battery.

There may be a temperature sensor in the intermediate connector and a bit of electronic/software wizardry involved.

 

 

Edited 7 April, 20206 yr by xman

The Superb’s battery is now fully charged so I’ve moved onto our Citigo. 
Problem: I can’t identify the battery type because there’s all sorts of electrical gubbins on top of the battery which I’m reluctant to remove (see photo). I’ve even RTFM to no avail. 
So, I’ve elected to charge it as though it is EFB, reasoning that this is less likely to result in an overcharge than if I select AGM and the battery is in fact EFB. 
I note that final float voltage on my CTEK charger is given as 13.6 V for both normal (FB & EFB) and AGM batteries so I’m wondering what the ramifications of charging an AGM as though it’s a EFB really are?

I’ll stop now as I’m confusing myself! But any advice on this (hello XMan) would be gratefully received. 

Looks like on the LHS you should be able to unclip the plastic and lift for access

Theres a Charge Eye in the lid - its not an AGM as they don't have that feature.

Also a small car so very unlikely to have AGM.

Edited 7 April, 20206 yr by BigEjit

Thanks TWM. I did unclip the plastic as you suggest (and a similar clip on the other side) but to no avail. I’m reluctant to really pull on it as, of course, if anything went wrong we don’t have Skoda dealer backup at the moment. 

BigEjit, thanks for this. I’ll go and have a look shortly to see if I can see electrolyte. Yes, I think Citigo unlikely to have AGM especially as my Superb 280 definitely doesn’t. 
just seen your edit re. charge eye. Fantastic! Many thanks. 

Edited 7 April, 20206 yr by Howardd

2 hours ago, Howardd said:

I note that final float voltage on my CTEK charger is given as 13.6 V for both normal (FB & EFB) and AGM batteries so I’m wondering what the ramifications of charging an AGM as though it’s a EFB really are?

Float voltage is ideal.

 

If you charge AGM using EFB program, it will not actually fully charge the AGM battery by the time the indicator thinks/shows its fully charged as AGM requires a higher charging voltage than EFB.

 

But leaving it on standby for a few hours should see it top off the AGM albeit slowly at float voltage.

 

Heres a handy chart to roughly estimate SOC vs resting voltage. Make sure the car has been stood at least an hour or two with nothing turned on before measuring. Everything needs to be off, doors closed etc for several minutes to make sure all electronics have gone to sleep.

 

Note: EFB = WET

 

 

Extra note: Actual voltages vary with temperatures and individual battery manufacturers so don't forget this is a rough guide.

 

Edited 7 April, 20206 yr by xman

Thanks again xman for a really helpful reply. Appreciated. 

Thanks all for the great info. Given my knowledge was very limited I followed CTEK advise “charge all auto stop/start batteries using AGM mode” and just found out my battery is EFB.

 

could I have caused damage to the battery by using the AGM mode two days in a row? 

It’ll be fine. AGM are more at risk of drying out if charged as a flooded battery, it doesn’t matter anywhere near as much EFB charged as AGM.
 

 

5 hours ago, BigEjit said:

It’ll be fine. AGM are more at risk of drying out if charged as a flooded battery, it doesn’t matter anywhere near as much EFB charged as AGM.
 

 

I find this all very confusing...

I thought all Stop/Start cars had to be charged using the AGM mode. So that's what I did the first time I charged my battery.

Then I read (on here I think) that no it should be charged as an EFB. So that's what I did the second time I charged it.

Now, as I say...confusion rules!!!

Don’t worry about it. Just let the charger get on with it. It’s not going to do any harm at all being a Ctek. There’s no electronics in a starter battery so you aren’t going to damage it by picking the wrong charging program once in a while for a quick top up charge. 
 

An occasional recharge esp on low mileage cars helps the battery stay at peak performance and allows stop start to operate more frequently - a good sign in itself that the battery is hunky dory. 

I’m looking at the CTEK mxs5, it comes with the M6 eyelets as standard, is that the size used on the superb bolts or is the M8 required?

xmans chart is interesting, My 2020 superb with 11k mileage on it starts ok for the 7 months i've had it BUT when at rest the voltage drops back down to 12.2v, ive had it checked by a battery specialist and he said its ok, When i drive it the voltage fluctuates all the way up to 14.8v, but an hour after stopping it goes back to 12.2-3 and its been like that months,  Its an EFB exide battery and i put it on charge last week with my Ring smart charger with EFB mode on and it charged to 12.6 in about 4 hours but within an hour or so it was back down to 12.2 again,  Question is this shall i ask skoda to change it because it's worrying me with the cold weather round the corner...ps i drive it for over an hour 3 times a week.

Can you charge start/stop superb using cigarette lighter plug like this https://www.ctek.com/uk/battery-chargers-12v-24v/ctx-indicator-plug-12v?

On 30/12/2021 at 10:46, Stuom said:

Can you charge start/stop superb using cigarette lighter plug like this https://www.ctek.com/uk/battery-chargers-12v-24v/ctx-indicator-plug-12v?

 

That’s what I do, with the non-indicator version that came with my CTEK charger.