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Battery degradation hidden in energy consumption?

theStig

Member
Apr 16, 2019
43
28
Vancouver
I've been noticing a lot of unaccounted for range loss over recent months. The latest update doesn't help.
I'm not a programmer but I believe the degradation may be hidden in the energy consumption, rather than the full charge amount.

I've documented my latest trip. This is a regular pattern even with higher temperatures.

SR+, chill mode, cabin heated up while plugged in
12c outside temp (53f) throughout the trip

Started with full charge of 377 km (used to get 386)
Drove 125 km (flat, 105 km/h average on highway)
Car shows 179 kms left

73 km lost

Return trip
added 45 km at a SC for a starting of 224 km
drove back 97 km
Car is left with 78 km

49 km loss

Total charged: 422
Total driven: 222
Remaining: 78

Total lost: 122
Percentage lost: 29%

Has someone been able to get into the cars software to analyze the algorithms and calculations for battery charge and range?

Showing a full charge close to the claimed range would avoid lawsuits and warranty claims.
All range loss issues would then be blamed on driving habits, temperature, wind resistance etc. which would be subjective and invalid as a claim. Tesla needs to be transparent with this programming.

Any thoughts?
 

Tam

Well-Known Member
Nov 25, 2012
9,524
8,655
Visalia, CA
...Showing a full charge close to the claimed range would avoid lawsuits and warranty claims...

A lawsuit based on the promise of your Model 3 warranty?

Your warranty specifically has a guarantee of 70% capacity.

That means if you thought you bought a 100% capacity at the delivery but then by the time you got home, you found out that you got only 70%, Tesla is still legally complying with your warranty.
 

gyozaman

Member
May 12, 2019
41
23
Vancouver
I have notice issues as well. There are other threads mentioning similar issues. I have a long range M3.
But for me, I have been driving with the energy screen on and toggling between 10 km and 25 km graphs.

Yesterday I fully charged to 100% at a SC (Surrey BC). I drove 12 kms home with 9km highway (90 km/hr) and the 3 km city street (50 km/hr). When I got home, my battery was 94% but my projected range was only 399 km. A 90 km loss after only driving 12 km.

Today I drove 30 km at a 50/50 mic of city and highway. When I got home my battery is 81% with a projected range of 282 km. So in 2 days I drove 42 km but loss 75 kms.

Heater was never on. Front Defroster at fan speed 1 was on 25% of the drives. It was raining but I don’t use my wipers as I coated windshield with Rain-X. Both trips did not have any hard acceleration at all.

Highways speeds are 90-110 km/hr and the energy graph shows massive draining of kw energy at these speeds.
 
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theStig

Member
Apr 16, 2019
43
28
Vancouver
12 degrees celsius. 35 feet above sea level, quite flat commute, 9km/h winds avg. Light rain. Typical Northwest day. Not that cold yet.

A 1/3 to half less deviation from the EPA rated 386 km is concerning. Especially for trips with limited charging infrastructure, which some of us have to do.

I haven't driven up the mountains yet, I'm not relaxed and enjoying this car's calculations enough to do that yet. I'm trying to understand it and want to know if anyone has analyzed it yet. That would be helpful in planning my trips.
 

VT_EE

Active Member
Apr 22, 2017
2,077
2,777
Maryland
I have notice issues as well. There are other threads mentioning similar issues. I have a long range M3.
But for me, I have been driving with the energy screen on and toggling between 10 km and 25 km graphs.

Yesterday I fully charged to 100% at a SC (Surrey BC). I drove 12 kms home with 9km highway (90 km/hr) and the 3 km city street (50 km/hr). When I got home, my battery was 94% but my projected range was only 399 km. A 90 km loss after only driving 12 km.

Today I drove 30 km at a 50/50 mic of city and highway. When I got home my battery is 81% with a projected range of 282 km. So in 2 days I drove 42 km but loss 75 kms.

Heater was never on. Front Defroster at fan speed 1 was on 25% of the drives. It was raining but I don’t use my wipers as I coated windshield with Rain-X. Both trips did not have any hard acceleration at all.

Highways speeds are 90-110 km/hr and the energy graph shows massive draining of kw energy at these speeds.
You do realize the car expends considerable energy heating the battery up to optimal temperature? You live in Canada. This drain is going to get worse as the temps go down.

Rain and snow cause considerable drag, which will also increase consumption.
 

theStig

Member
Apr 16, 2019
43
28
Vancouver
Was this considerable energy expenditure made clear to you during purchase on the website or in person through a Tesla sales associate in store?

I was not, so I only realize after the fact through my experience and these forums.

Looking at the site today, I do not see any clear literature on this. Gas savings based on an average EPA consumption is very clear.
 

Matt L

Active Member
Jul 20, 2018
1,050
1,685
OK USA
Was this considerable energy expenditure made clear to you during purchase on the website or in person through a Tesla sales associate in store?

I was not, so I only realize after the fact through my experience and these forums.

Looking at the site today, I do not see any clear literature on this. Gas savings based on an average EPA consumption is very clear.
Do gas cars come with the same information? Have you felt cheated with every car?
 

SSedan

Active Member
Jul 24, 2017
2,948
2,590
Greenville Wisconsin
Cold weather and tires pumping water out of the way will reduce range, you just never obsessed over it with ICE.

I will agree that more should be said about range loss in winter, I try to share my experiences. You will quickly get a feel for it.

Also when charging over 90% part of the reason for accelerated range loss is the lack of regen.
 
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bogich

Member
Mar 17, 2019
28
50
Virginia, US
It got colder in the northern hemisphere, which causes range loss and higher Wh/m.
My humble advice - relax, enjoy the car, and if you still think buying it was a mistake, just sell it. The resale value is great compared to other brands.
In my view 20% to 30% higher energy use is to be expected, when interior or battery heater is to be used, especially on a rainy day, where there is higher drag.
Besides, this car does not have a heat pump. I would suggest - try Hyundai Kona, might do better in the cold(FWD, heat pump, bigger battery), but please do not complain if it is not even half as fun as M3! :)
 

KenC

Active Member
Sep 4, 2018
3,769
3,502
Maine
Both in Vancouver? Call Fox Mulder. Or it could be the metric/imperial conversion playing tricks on you.

All jokes aside, rain can easily add 5% to your consumption, and temps, in the low 50s can easily knock off another 10% from the 70s. Still, seems hard to explain all the range loss.

Here's my efficiency vs temp chart:
IMG_3968.jpg
 
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ZOMGVTEK

Member
May 19, 2015
559
442
'Merica
Was this considerable energy expenditure made clear to you during purchase on the website or in person through a Tesla sales associate in store?

I was not, so I only realize after the fact through my experience and these forums.

Looking at the site today, I do not see any clear literature on this. Gas savings based on an average EPA consumption is very clear.

There’s no doubt Tesla could do a better job explaining this, especially since so many people appear to be entirely baffled how much has impact on consumption. Almost everything impacts consumption. Speed, temperature, road and weather conditions are big ones. This is the unfortunate reality, and it impacts all vehicles, so presumably Tesla is avoiding brining it up since it’s not specific to them or EV’s. It’s easy to get single digit MPG’s in a combustion car rated for 40. It’s very uncommon for so many people to track consumption as closely as they do with EV’s, so this largely goes unnoticed. People just put more fuel in. Strangely this isn’t the case with an EV, people loose their minds at the perception of battery degradation or worse than expected range, even if it’s not really an issue. Somewhat understandable, but yet Tesla isn’t doing anything out of the ordinary. A battery holds energy, just like a tank of fuel. How far you can go with that energy is going to vary a LOT based on the conditions you drive in. For some people, they will deplete a full battery having never moved one mile, and it’s also possible for that same car to go twice as far as the EPA says at very low speeds and ideal conditions. So it’s really challenging to say how far your car will go in your conditions. Its largely up to the operator to use their judgement and make an educated guess based on predicted conditions and experience, just the same as it’s always been.
 

SageBrush

REJECT Fascism
May 7, 2015
12,590
16,783
New Mexico
OP: it is you and the weather, not the car.

You
Heater and dehumidifier use
Possible more brake use

Weather
Decrease in tyre pressure
Increase in air density
Higher road friction
Colder battery

You can reduce the winter related consumption a lot if you care to learn and adapt a little rather than just cast about for someone to blame.
 
Last edited:

AlanSubie4Life

Efficiency Obsessed Member
Oct 22, 2018
10,924
13,719
San Diego
Started with full charge of 377 km (used to get 386)
Drove 125 km (flat, 105 km/h average on highway)
Car shows 179 kms left

You drove at:

(377rkm-179rkm *130.5Wh/rkm)/ 125km =
207Wh/km (331Wh/mi)

Return trip
added 45 km at a SC for a starting of 224 km
drove back 97 km
Car is left with 78 km

(224rkm-78rkm)*130.5Wh/rkm/ 97km =

196Wh/km (315Wh/mi)

That was your trip meter efficiency on the return assuming your data is good.

Total charged: 422
Total driven: 222
Remaining: 78


You used 198rkm + 146rkm = 344rkm

to travel 222km.

Means you drove a factor of 344/222 above rated efficiency of 130.5Wh/rkm (209Wh/mi)

which means you did on average:

130.5Wh/rkm*344rkm/222km = 202Wh/km

To me this seems a bit high overall for a flat drive even when running heat, at 105km/h. But it is conceivable if it was windy or rainy. I do wonder if you were careful to track all your losses when parked though.


Has someone been able to get into the cars software to analyze the algorithms and calculations for battery charge and range?

Yes, sort of, there is very little analysis required though, see this post:

Suspicious range numbers

Feel free to post detailed trip meter data and rated miles before and after if you still have questions. It is pretty straightforward though; rated km use is completely deterministic and predictable, except in some rare special cases where something goes wrong.

If the overall picture still does not make sense with the trip data, etc., then maybe there is something wrong. But likely it will make sense if we look at the numbers.
 
Last edited:

AlanSubie4Life

Efficiency Obsessed Member
Oct 22, 2018
10,924
13,719
San Diego
.
See this topic:

V10 and Battery "Degradation"

Also check my message from Model S battery degration topic. We should investigate this little further on.

Somebody else has reported 7-10 % drops on range after version 10.

Sudden Loss Of Range With 2019.16.x Software

While there are certainly cars with range loss as referenced in these threads, the OP’s thought that the range loss is “hidden” cannot be supported with available data. Even in these threads, the vehicles with loss of range show a reduced number of available rated miles/km. It is not hidden.

The OP’s issue is (apparently) just an issue of driving above rated consumption due to whatever factors.

That is distinct from range loss. Unless Tesla is being super duper tricky and changing the trip meter Wh/mi scaling. (Which is pretty unlikely.)
 

SammichLover

Banned
Dec 8, 2018
2,618
1,651
Yup
rain can easily add 5% to your consumption,
More like easily 25% if it is actively raining hard anywhere around highway speeds. Not just pushing water with your wheels, pushing a lot of water with the body of your car as you constantly run into a stream of slow moving droplets.

The same amount of energy lost with an ICE vehicle, just easier to notice in a BEV because the ICE has all that other inefficiency to cloak over these losses so % of total fuel use is a somewhat smaller number.
 
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