284 mile range after 15.5k miles - what’s going on?

[olerass]

I got the feeling that my M3P battery has degraded too much. It’s 1 year old, has driven 15500 miles (25000km), and displays 284 miles (457 km) range at 99% (I can rarely charge it to 100% anymore), a degradation nearing 10%.

Today I took it on a long trip starting from 99% and driving it down to 3%. In this time it used only 62kWh. Where did the remaining 13 kWh go? Is this really normal or should i get it looked at? According to TeslaFi my range degradation is far worse than others (the blue line is mine), but I’m not sure how accurate it is:

I charge daily to 80%, occasionally (every month) go below 10%, and rarely charge to 100% (maybe 5 times in total). I use the car for normal driving to and from work. No track racing if anything like that.

 

[Zoomit]

If your battery doesn’t experience occasional idle storage periods when above 85% SOC, the 96 bricks will become imbalanced and your available battery capacity will be diminished. If you want to read the Tesla Service Manual section on this, here ya go.

Brick Balancing​

Note that the capacity of a pack is limited by the brick with the lowest capacity. When that brick is charging, it will gain voltage faster than other bricks. The HVBMS will stop charge when any brick reaches its ceiling voltage (~4.2V). If one brick has a significantly lower capacity that others, the pack will be limited by that brick which will get to 4.2V faster than the other ones. We refer to the brick with the lowest capacity as: min CAC. In periscope, its value can be seen by viewing the signal: 'BMS_cacMin'

Another limitation could come from bricks being imbalanced, or some bricks with a voltage higher/lower than others. This would limit ability to charge the pack as the brick with a higher voltage than others would reach the ceiling voltage early. Same idea when discharging, the brick with the lowest voltage would hit the floor voltage early which would cause the HVBMS to open contactors from low power​

To mitigate this imbalance, Batman has some bleed resistor that can be placed and removed in parallel of each brick via a FET relay. Batman can put that resistor across the brick with the highest voltage which would slightly discharge that brick and bring it back to the level of the other bricks. Batman closes a FET which puts that resistor across the brick. The HVBMS will order Batman to put that bleed resistor across the brick with the highest voltage when Delta V is > 5mv MinBrickV > 4.0v (~85% SOC) && HVBMS State == STAND BY.​

Note that Batman can also do balancing when the HVBMS is asleep.​

The best way to balance the Model 3 pack is to set charge limit to 90% or higher and let the vehicle sit idle for hours (plugged in or not). 24 hours of balancing can reduce imbalance by 1mV.​

Note, this is a totally different issue from BMS calibration error, which may be a factor here as well.

 

[KenC]

Stopping at 99% is indicative of cell imbalancing. Charge to 90% for a week. Also TeslaFi is temp-dependent, so some of the drop could be Winter temps, that Spring should be reversing. You should probably take it to your service center and have them check, since it seems you only have 64.5kWh usable.

 

[Uncle Paul]

Watching all the TeslaFi data can drive you crazy. Just enjoy your new car.

 

[InternetDude]

Watching all the TeslaFi data can drive you crazy. Just enjoy your new car.

That’s a very ignorant and unhelpful reply. It’s not a “new” car, it’s 1 year old and he’s experiencing something abnormal regarding range and capacity. To the OP, I suggest you read the forums here some more and talk to Tesla to have them check into it. And by talk to them I don’t mean phone them because that’s impossible. Use the app for support.

 

[olerass]

@Zoomit thanks that’s very helpful. I’ve had the car sit at 92% since you posted this but there’s still no change in the range displayed. Is it unrealistic to expect it to climb a few km over two days if it a balancing issue?

 

[WarpedOne]

It will climb after next charge. Imbalance accumulates slowly and it also decreases slowly.
There are just two options: there is something wrong with your pack or it is not. Only service can tell.

 

[Zoomit]

[QU

@Zoomit thanks that’s very helpful. I’ve had the car sit at 92% since you posted this but there’s still no change in the range displayed. Is it unrealistic to expect it to climb a few km over two days if it a balancing issue?

As @WarpedOne mentioned, it'll probably take a recharge or two to see the difference. It wouldn't hurt to drain it to below 15% and charge it above 90% to help reset the Battery Management System calibration. I'm not positive what charge levels are critical for this but 15 and 90% are probably good.

 

[toolman335]

How often do you charge it to 99%, and why do you do it? What is the typical level that you charge it to?
When you went from 99% down to 3%, how many miles of range did you get? I find that the miles estimate is always way off. In nice weather I know I could get 320+ if I drove it to zero.
I've learned a few things in my 8 months of ownership.
1- If you have to charge it to 100%, don't leave it sitting at that charge level. That is only for a long trip and make sure you charge to that level and begin driving asap.

2- Many might disagree with me, but I find that 90% is a great level to charge to. About once a month I top off to 100% for a long trip and run it down to 10% or so. That seems to reset everything. People who charge to 60-80 seem to report degradation/range loss issues more often than the 90 crowd(yes I know I'll catch heat for that lol).

3- At the 6 week mark my 100% was down to 290. Now it's back up to 308. Natural fluctuation due to many variables is ok. Don't lose sleep over it.

 

[olerass]

I just got off the phone with a Tesla service technician who took a good look at my car and its data on the 99% to 3% drive. All in all everything seems to be ok and as expected. This was his main points:

• The kWh display in the car under trip/since last charge does NOT currently include power used to heat the battery, aircon and the 12v subsystem. It used to do this in previous updates but it doesn't anymore. He could see from their logs that my car spent 15-20% of it's power on this, which fits pretty well with the difference between the reading on my display (62kWh), the actual battery size (75kWh) and the amount spent here (20% of 75 = 15 kWh, 75-62 = 13 kWh).

• The range displayed next to the battery icon (the one that can be changed between range and %) is based on my driving style and thus is different from every car and driver. I specifically remember reading some posts about this NOT being based on driving style, but he said that there's confusion because Tesla has changed how it works multiple times, and the several last updates have ben based on driving style but former ones it was not.

• The car apparently spends energy heating the battery. I was under the impression that M3 only heats battery from waste energy from the motors, but he said that it actually also heats the battery using some other mechanism (something with oil, don't remember the exact details).

• My battery does not have any significant imbalance. I asked him specifically if he could see this at his end and he confirmed.

All in all my stats look fine according to Tesla. I'm not sure what to believe since I read multiple sources that contradict the above information, but to be fair that could also just be out of date info as he said.

I hope this can help anyone else with the same issues/concerns. I plan on taking the car for a long drive when it gets real summer (it's only 15c here now), without AC, to confirm the kWh usage gets a lot closer to 75kWh due to no ac and less need to heat battery. Only then will I have true piece

 

[KenC]

I just got off the phone with a Tesla service technician who took a good look at my car and its data on the 99% to 3% drive. All in all everything seems to be ok and as expected. This was his main points:

• The kWh display in the car under trip/since last charge does NOT currently include power used to heat the battery, aircon and the 12v subsystem. It used to do this in previous updates but it doesn't anymore. He could see from their logs that my car spent 15-20% of it's power on this, which fits pretty well with the difference between the reading on my display (62kWh), the actual battery size (75kWh) and the amount spent here (20% of 75 = 15 kWh, 75-62 = 13 kWh).

• The range displayed next to the battery icon (the one that can be changed between range and %) is based on my driving style and thus is different from every car and driver. I specifically remember reading some posts about this NOT being based on driving style, but he said that there's confusion because Tesla has changed how it works multiple times, and the several last updates have ben based on driving style but former ones it was not.

• The car apparently spends energy heating the battery. I was under the impression that M3 only heats battery from waste energy from the motors, but he said that it actually also heats the battery using some other mechanism (something with oil, don't remember the exact details).

• My battery does not have any significant imbalance. I asked him specifically if he could see this at his end and he confirmed.

All in all my stats look fine according to Tesla. I'm not sure what to believe since I read multiple sources that contradict the above information, but to be fair that could also just be out of date info as he said.

I hope this can help anyone else with the same issues/concerns. I plan on taking the car for a long drive when it gets real summer (it's only 15c here now), without AC, to confirm the kWh usage gets a lot closer to 75kWh due to no ac and less need to heat battery. Only then will I have true piece

Interesting, but as you already know, alot of us would disagree with the tech.
• if the display changed its methodology in what it included in usage, Tesla should have informed us. Imagine all the people who would do the math, like you did, and think something were wrong. Why hasn't that happened?
• driving style? No. Why would Tesla change how it works multiple times? Why cause confusion? Why wouldn't this new range display now match the trip display?
• I think he said the same thing; the motor passes wasted heat into the oil/fluid, which then gets circulated to the battery.
• 99%, indicates only a small imbalance, probably not "significant".

 

[animorph]

Our Model 3 battery chart looks like the OP's but I haven't checked in with Service yet. Several TMC members seem to have the same problem, but many don't.

Here's one possibility:

Reduced Range - Tesla Issued a Service Bulletin for possible fix

OP is in Denmark. That car's battery display will be different, so we can't really say much from a U.S. point of view. Otherwise, I'd think the Service guy was making stuff up again.

At the very least, yes there are energy losses that are not measured, not the least of which are internal battery losses. That's why the trip kWh energy used number is always low. If you drive slow it will be closer to actual battery capacity. If you drive faster it will be lower.

 

[woodguyatl]

@Zoomit thanks that’s very helpful. I’ve had the car sit at 92% since you posted this but there’s still no change in the range displayed. Is it unrealistic to expect it to climb a few km over two days if it a balancing issue?

I regularly charge to 80%. I experienced the same issue as you. I’ve left the car set to 90% for past few weeks. Estimated range at 90% has slowly but consistently increased over the last month. It might be slow because we are hardly driving it or perhaps it is just a slow process to balance the cells.

 

[toolman335]

Every time I supercharge it lowers the range by 1 or so miles.
When I go a few weeks of charging at home to 90% it slowly creeps back up.
It's just a number. Your driving style and climate conditions are what will determine how much range you get. Stop stressing.

 

[mtndrew1]

I bought the Remote for Tesla app and it has some more granular information.

On the lower display it appears to show the kWh remaining out of total kWh pack capacity and indicates my total pack capacity is currently 68.9 kWh.

I’m not sure where this information comes from or if it includes the pack buffer but it would corroborate the range loss displayed on the screen.