I ased my contact at Skoda UK how the 12 volt battery is charged, since there isn't an alternator and this is the answer I received.

 

I can confirm as your vehicle is a Hybrid model hybrid vehicle it does not have an alternator. Your vehicle is equipped with a three-phase current drive which can act as the sole drive for the vehicle or in combination with the combustion engine. It also performs the tasks of the starter and alternator. While driving your vehicle it will put a small percentage of charge back in to your battery through recuperation. However, the main battery re charge will come from physically plugging your vehicle in to be charged. Regarding your 12volt while the vehicle is in Hybrid mode I would also advise you to refer to your owners manual. This will explain the system in more detail specifically relating to:
• Starting and driving
• Select Drive
• Operation
Press the mode button
You can see the state of charge in hybrid mode
Driving with hybrid drive - charging the high-voltage battery operation
Driving with hybrid drive - Maintaining the state of charge of the high-voltage battery » Operation.
This replenish the HV battery when vehicle is in motion not the 12v battery which maintains its power from the HV battery.

 VagProf's reply on an earlier thread was more helpful on this matter.

Edited 2 August, 20214 yr by Jim2015

Jim - I recently raised this question of charging the 12v battery with the Octavia specialist in CZ. He bounced it back to Skoda in Sheffield (?main customer services centre) who replied to me word-for-word the same as the response you received, so a bit of cut & paste going on there, I think. They added in the reply to me that I ought to buy a home charger. In 50+ years of motoring I have never needed, or used, a battery charger; is this progress? Lady Norris is heavily narked about this and says if that's the case they should supply 12v chargers with the cars.

 

I replied like this (my remarks in Bold) :

 

You say "For the most efficient charging I would advise a home charger". If the 3-phase current drive performs the task of the alternator, why do I need a home charger? 

 

And "charging from the mains socket or domestic or public AC charger is to the HV battery but the vehicle is equipped with Power and control electronics for the charging of the 12-volt battery and the supply to the vehicle electrical system". So, again, why do I need a home charger?

 

Their subsequent reply addressed only the HV battery (which I charge several times a week using the supplied lead plugged into a domestic outlet), so that reply was no use. So for when the car is not used for several days it looks like I have no alternative but to buy a battery charger. I said above that I have not used one before, but what I have used over a period of 12 years is a CTEK battery conditioner for a Caterham and then a Morgan. Worked like a dream. 

 

I'd be grateful therefore is anyone can offer any advice on which charger I should buy (indeed, what type of battery is fitted in these hybrids - lead/acid, gel, AGM, SLI ?). Having used CTEK conditioners previously I am leaning towards something like this. 

The deal is that the 12V battery is charged by the High Volt (HV) battery and the HV battery can be charged by the ICE (in some modes on the Superb iV which is essentially the same setup as the Octavia iV/Glof GTE/Passat GTE etc) or when plugged into the mains.

 

There is no requirement to charge the 12V battery by itself - the car does that in the background all by itself.

 

I think the Skoda response about a charger refers to the most efficient way to charge the HV battery (not the 12V battery) - ie a wall charger will charge at a higher rate than using the 13 amp plug/lead option. 

14 minutes ago, aerofurb said:

The deal is that the 12V battery is charged by the High Volt (HV) battery and the HV battery can be charged by the ICE (in some modes on the Superb iV which is essentially the same setup as the Octavia iV/Glof GTE/Passat GTE etc) or when plugged into the mains.

 

There is no requirement to charge the 12V battery by itself - the car does that in the background all by itself.

 

I think the Skoda response about a charger refers to the most efficient way to charge the HV battery (not the 12V battery) - ie a wall charger will charge at a higher rate than using the 13 amp plug/lead option. 

The Octy iV has a 3,5kW onboard charger, so a higher-rated wall charger will be no better than a 13-amp socket. However, an answer in another thread stated that a wall box was being installed whilst grants are still available to future proof the owner as in future an EV may be purchased.

My point was actually one regarding the charging of the 12V battery - not the HV battery charge rates.....

 

I stand to be corrected but I was under the impression from my research (I looked at an Octavia iV vRS versus the Superb iV Sportline Plus but went for the Superb given the various reports of the Octavia Mk IV infotainment/software 'issues'...) that the 'running gear' was effectively the same between the Octavia iV and Superb iV (and the VW etc counterparts.

 

Looking at various sites, they all claim the charge rates on the Octavia iV and Superb iV are the same as each other and quicker via a wall box than using the 13 Amp standard UK domestic power supply. Apparently, you don't get the full 3.6kW out of the standard plug socket.

 

 ŠKODA Octavia iV (2020) Charging Guide | Pod Point (pod-point.com)

 

ŠKODA Superb iV (2020) Charging Guide | Pod Point (pod-point.com)

 

 

 

 

Anyway, I'll slope back off to the Superb forum, as I was saying, I was just trying to assist with the query over the 12V battery charging query.

 

 

 

3 hours ago, aerofurb said:

Apparently, you don't get the full 3.6kW out of the standard plug socket.

Let's do the simple maths - voltage from 'normal' 13A socket = 220V -10% +20%

 

13A @ 220V -10% (198V) = 2.57kW

13A @ 220V (nominal) = 2.86kW

13A @ 220V +20% (264V) = 3.43 kW

 

So even if you are lucky enough to have the maximum voltage specified for a UK single phase supply you can only get 3.43kW - getting this maximum voltage is very unusual (the maximum I've ever seen in a domestic installation is 240V (the old pre-harmonised nominal voltage) which corresponds to 3.12kW.