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Discussion Starter #1
At my 30k service I asked if they had a battery condition report as I was concerned my battery had lost a significant amount of capacity as my electric range averages 24-22 miles then drops after 0.5mile to 19miles and my average consumption is 54.3 mpg which is a third of the 166mpg advertised !

The battery was inspected and tested in at MK Audi they said it would only take an hour so I waited. Turns out my battery is fine and has lost 2ah out of 25ah which equates to a 8% loss of capacity over 30k miles. This means that at that rate of loss, at 100k when the warranty expires (at my yearly millage I should hit before the 8 years is up) I will have lost 6.66ah or a 27% capacity loss which is just shy of the 30% needed to have battery replaced under warranty. This assumes a constant loss figure , batteries don't always decline with a linear curve.... So I may end up with a replacement at this level of degradation.

The cell voltages were all the same which is good as it means the car is wearing the battery evenly. They all read 3.67v and I count 96 cells giving 352v which is bang in the middle of what the pack should provide 280v-390v (the car was at about 50% charge when I took it in) . Interestingly if you then figure out the capacity in kWh it comes out to 8.8kWh at this voltage which is the quoted capacity of the pack. The useable figure is only quoted at 7kWh

(I may of done some maths wrong here.....)

So it looks like the loss figure is probably accurate given rounding errors etc...

So with a battery that is in manufacture spec on a car that is still in warranty I am filling to get even slightly close to the quoted figures I was sold the car on . I realise there are lots of other factors involved but 1/3 of the quoted figure is not acceptable.

I really do wonder how they got to a 30mile range and 166mpg figures ! I have never had a car which the consumption is so different to the manufacture quoted figures......

In summary it looks like the technology is good and working as intended, just that what I was sold as far as range and consumption was greatly over estimated...

Anyone else had one of these reports done ?

upload_2019-3-14_17-54-26.jpeg
upload_2019-3-14_17-54-26.jpeg
 

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Obviously, they merely downloaded what the BMS is telling them.

Whether the battery can and does deliver what the BMS says it can is a completely different matter, as they didn't test it.
 

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Discussion Starter #3
I don't know if that was necessarily the case I wasn't told exactly what was involved, but I'm fairly sure they didn't take the car for a test drive. they must complete some kind of load test though ?

From the data and what I have calculated myself it seems the pack is working as intended. My issue is the car doesn't offer anything close to what I was told when I bought it .

I'm very interested in other peoples experiences ........
 

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The NEDC figure pre-assumes a certain mix of EV versus ICE driving.

You are evidently not following that mix.
 

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Discussion Starter #5
Do you have a link to what that data is ? Do you know what tests I should be asking them to perform ? My car suggests the mix is about 50/50
 

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Any PHEV has an absolutely massive range of MPG, depending almost entirely on the pattern of driving and the driver.

For example, I owned a Prius Plug-In for nearly five years. IIRC, the "official" mpg figure for that was something like 135mpg. The actual mpg I got varied from about 65mpg to around 170mpg, depending almost wholly on the distance driven, speeds etc.

Over the five years I owned it the average was somewhere around 145 to 150mpg, but that was dominated by a 16 mile each way commute every weekday, where I could charge at both ends. Going on holiday the consumption would drop right down to 60 to 70mpg, less on any motorway trips.

The standard mpg test methodology isn't geared up to be able to deal with PHEVs, and often gives meaningless predictions. If my daily use had been my old commute, of around 50 miles each way on mainly a fast dual carriageway, with no opportunity to charge at work, then over five years I doubt that the Prius Plug-in would have averaged half the advertised fuel economy figure.
 

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The longest range I have achieved on my GTE with a brand new battery is 22 miles.

To get the NEDC range you would essentially have to drive at 30-40 mph continuously. It is an outdated system for measuring range, with a top speed of 30 mph for most of the drive cycle and only a brief spike to 75 mph.

Do you drive like this? Don't think so.

http://www.car-engineer.com/wp-content/uploads/2012/12/NEDC.png

NEDC is a stupid, outdated system of measuring range and economy of vehicles; it is depressing that it is still used.

Further, the loophole that PHEVs exploit to get 150+ mpg is that they are tested starting with a full battery. So, they consume relatively very little fuel by the end of the cycle (I believe it's repeated a few times; most PHEVs could do the first cycle on a full battery.)

The problem is, manufacturers like VW and Audi are not allowed to advertise any figure other than NEDC.

So you will continue to see this hilariously outdated range figure on PHEVs and BEVs. Luckily, WLTP testing will be mandatory soon on EVs, and this range figure should be more accurate.

When I come to power (a terrifying thought for anyone who knows me!) I would make it mandatory for car manufacturers to offer several "real-world" figures for all vehicles:

- Fuel economy / electric efficiency or range in urban cycle (Artemis)
- Fuel economy / electric efficiency on range in rural cycle (Artemis)
- Fuel economy / electric efficiency or range at a constant 130km/h / 70mph
- The above three figures available at 0'C, 15'C and 30'C with climate control set to a steady 18'C with air con on if needed.
 

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Discussion Starter #9
Thanks I get what your saying and understood a lot of what would effect the consumption due to my usage style which is completely random. What I was told though was the car would function as an efficient hybrid when not in EV or Dynamic. I never thought I would get 160mpg but I am sorely disappointed I don't get more than my old diesel !

The whole point of the test i had done today was to confirm the battery was good and my issue was my expectations from what I was told when I bought the car.

I also hope that the iso may help other people who are in a similar situation. The dealer I am speaking too has said here have been "quite a few people" who have been very disappointed with the cars and had these checks done to confirm if there were issues
 

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Discussion Starter #10
The longest range I have achieved on my GTE with a brand new battery is 22 miles.

To get the NEDC range you would essentially have to drive at 30-40 mph continuously. It is an outdated system for measuring range, with a top speed of 30 mph for most of the drive cycle and only a brief spike to 75 mph.

Do you drive like this? Don't think so.

http://www.car-engineer.com/wp-content/uploads/2012/12/NEDC.png

NEDC is a stupid, outdated system of measuring range and economy of vehicles; it is depressing that it is still used.

Further, the loophole that PHEVs exploit to get 166 mpg is that they are tested starting with a full battery. So, they consume relatively very little fuel by the end of the cycle.

The problem is, manufacturers like VW and Audi are not allowed to advertise any figure other than NEDC.

So you will continue to see this hilariously outdated range figure on PHEVs and BEVs. Luckily, WLTP testing will be mandatory soon on EVs, and this range figure should be more accurate.

When I come to power (a terrifying thought for anyone who knows me!) I would make it mandatory for car manufacturers to offer several "real-world" figures for all vehicles:

- Fuel economy / electric efficiency or range in urban cycle (Artemis)
- Fuel economy / electric efficiency on range in rural cycle (Artemis)
- Fuel economy / electric efficiency or range at a constant 130km/h / 70mph
- The above two figures available at 0'C, 15'C and 30'C.
I completely agree just feel like I am a beta tester in a car I have spent a lot of money on and intended to keep for a long time ....
 

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it sounds to me as if your expectations were falsely raised by the mythical numbers from official testing. TBH I doubt that this is that uncommon. I've owned hybrids, a plug in hybrid and now a BEV with range extender, since 2005. I've got very used to the way that the official test figures are complete garbage. It doesn't matter what the make of car, as the test figures are dictated by a common process, one that give very misleading results for PHEVs, in particular.

The biggest single factor, apart from the pattern of use, driver behaviour, etc, is outside air temperature. Hybrids, and to a much greater extent PHEVs, have a very wide winter to summer mpg variation. Winter consumption in my Prius PHEV used to be around 115 to 120mpg, summer this would increase to 165 to 170mpg. The hybrids I had before were similar, with winter often giving less than 50mpg, and summer giving well over 60mpg.
 

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Discussion Starter #12
it sounds to me as if your expectations were falsely raised by the mythical numbers from official testing. TBH I doubt that this is that uncommon. I've owned hybrids, a plug in hybrid and now a BEV with range extender, since 2005. I've got very used to the way that the official test figures are complete garbage. It doesn't matter what the make of car, as the test figures are dictated by a common process, one that give very misleading results for PHEVs, in particular.

The biggest single factor, apart from the pattern of use, driver behaviour, etc, is outside air temperature. Hybrids, and to a much greater extent PHEVs, have a very wide winter to summer mpg variation. Winter consumption in my Prius PHEV used to be around 115 to 120mpg, summer this would increase to 165 to 170mpg. The hybrids I had before were similar, with winter often giving less than 50mpg, and summer giving well over 60mpg.
My expectations were that a 2017 PHEV with a much lager battery would perform better than a 2008 Prius my Father owned, even if just being used as a hybrid ! It's frustrating as the rest of the car is really nice
 

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Thanks I get what your saying and understood a lot of what would effect the consumption due to my usage style which is completely random. What I was told though was the car would function as an efficient hybrid when not in EV or Dynamic. I never thought I would get 160mpg but I am sorely disappointed I don't get more than my old diesel !
The biggest issue with the GTE and e-tron is that it was always considered as a short range battery EV, with a petrol engine for power boost, performance and longer distances. In this configuration it is a fantastic vehicle. It achieves the performance of a GTI without the fuel economy compromise of a 2 litre engine. The 1.4 litre engine sips fuel when you consider that the car can output over 210 hp under acceleration. Most of the time, the e-motor net power is zero, and the net efficiency of the car is roughly the same as a 1.4L Golf TSI - i.e. about 45-to-the-gallon. However, expecting it to behave well as a regular hybrid is going to be disappointing.

If it was designed as a proper hybrid, then it would be designed a bit like the Prius, with a planetary gearbox, tiny efficient engine, and dual motor/generator setup. That setup can deliver 70+ mpg on motorway cruising, but comes with a significant compromise in terms of performance. It is however possible to make a "sporty" Prius; for instance, the Lexus 250h has 187 hp, almost as much as the GTE/E-tron.

The problem with the GTE is it just uses a regular six-speed gearbox and a single electric motor. This restricts the operation of the engine and e-motor to the crankshaft RPM. All it can do in hybrid mode is recuperate energy from braking and hills, and supplement operation of the engine during acceleration. However, it cannot keep the engine at an optimal load point at all times, and so will not most efficiently use the engine at all times.

The Prius arrangement allows the engine to operate at an ideal RPM for the given load point, further improving efficiency beyond a regular hybrid. The motor-generator setup acts as a variable speed gearbox essentially giving the vehicle a CVT without all of the headaches of a real CVT (Toyota call it e-CVT.) However, this would be a significant deviation from the Golf/A3 line, and it removes some of the sporty elements of the GTI. People don't enjoy their engines sitting at redline during acceleration; they like shifting through gears and they like "kickdown", even though the e-CVT is the most efficient configuration in terms of power delivery. So this is probably why VAG didn't use this configuration.
 

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Discussion Starter #14
Thanks really good explanation. Wish I had had it explained to me like that when I was buying the car would of managed my expectations.... potentially not bought it with the type of driving I do. One thing for sure the next car will be an EV loving the EV mode feeling and sounds =)
 
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