Percentage or Miles/Kilometers : which do you use and why?

[MaryAnning3]

% is a metric humans are accustomed to as its normalized to 0-100.

Even though this is technically a matter of opinion, I feel strongly that percent is the right answer. Partly, it is a matter of time scales. Degradation occurs on time scales of months or years. You don't need to be thinking about and remeasuring your battery capacity everyday. You can do that once a month or less. On a daily basis, you need to make smart decisions regarding when to charge and how high, and what you need to make those decisions is percent. For example, at a supercharger I might charge from 15% to 80% knowing that I will arrive at my destination 84 miles away at 50%. Focusing on percent will help you naturally make good decisions and extend your battery longevity.

To estimate range I use 28 miles per 10 percent, which is 84 miles per 30%, and do a little interpolation as needed. Every month or two I check my mileage range and it is always excellent. (You can do that, for example, at 67% and multiple by 1.5 (roughly); no need to charge to 95% or something, which is probably not great for your battery just for the purpose of a measurement.)

Using percent will help you take care of your battery and that will keep that number (range in miles), that you are not checking, nice and high!

 

[Kenz]

I wish Tesla would show both side by side and do away with the toggle.
There is plenty of room to show both.
Maybe if enough people ask for it they will show both.

 

[JulienW]

I wish Tesla would show both side by side and do away with the toggle.
There is plenty of room to show both.
Maybe if enough people ask for it they will show both.

Kinda have a solution and what I'm using. Tried Miles agin but just don't like since they are not relative to my driving. The Stats app shows all 3 Tesla Rated Range (Miles), Percentage of charge and Estimated Range (Miles). Have an Apple Watch and have the Estimated Range as a Complication (top right and can Select % or Rated Rage) and now I'm using Percent on the my 3. Not ideal but gives me both. Just leaves off Tesla Rated Range but again don't find it insightful for me.

 

[Firetechy]

I know that it has been discussed at length that the available mileage is "EPA ideal" and a "perfect conditions" estimate.

I humbly disagree with the assertion. Given my observations and testing, I believe it is learned based on usage by the vehicle/vs available battery capacity. I have, on 4 separate times, increased my available mileage by driving for a charge or 2 at 60MPH or less.

Purchased my M3MR in March. My normal commute is 100mi round trip at 70-75 MPH, which consumes more energy (248 Wh/mi average.) Within the first few weeks of ownership, I "lost" 5-6 miles of range.

BTW... I have only SC'd 3 times, all other charging is L2.

I noticed the increase the first time after a trip from the house and back that took the battery down to 20% SOC. Averaging 198 Wh/mi, when I charged back up, I had close to original mileage available (projecting from 85% charge.)

I have also noticed that my "EPA ideal" miles are much less than what I will have projected in the energy usage graph. To confirm, I would go back to commuting and then do it again and would have the same results (with my distance traveled and projected usage equaling the original range.) During these 60 MPH limit trips, I would add distance traveled to projected and routinely met the rated mileage of the battery.

So, I know YMMV but I have done this 4 if not 5 times with the same results, which tells me that this is not a static projection and must be, at the very least influenced, on vehicle consumption vs miles traveled.

-FT

 

[darth_vad3r]

I know that it has been discussed at length that the available mileage is "EPA ideal" and a "perfect conditions" estimate.

I humbly disagree with the assertion. Given my observations and testing, I believe it is learned based on usage by the vehicle/vs available battery capacity. I have, on 4 separate times, increased my available mileage by driving for a charge or 2 at 60MPH or less.

Purchased my M3MR in March. My normal commute is 100mi round trip at 70-75 MPH, which consumes more energy (248 Wh/mi average.) Within the first few weeks of ownership, I "lost" 5-6 miles of range.

BTW... I have only SC'd 3 times, all other charging is L2.

I noticed the increase the first time after a trip from the house and back that took the battery down to 20% SOC. Averaging 198 Wh/mi, when I charged back up, I had close to original mileage available (projecting from 85% charge.)

I have also noticed that my "EPA ideal" miles are much less than what I will have projected in the energy usage graph. To confirm, I would go back to commuting and then do it again and would have the same results (with my distance traveled and projected usage equaling the original range.) During these 60 MPH limit trips, I would add distance traveled to projected and routinely met the rated mileage of the battery.

So, I know YMMV but I have done this 4 if not 5 times with the same results, which tells me that this is not a static projection and must be, at the very least influenced, on vehicle consumption vs miles traveled.

-FT

What’s throwing you off is that there is recalibration ongoing, but that is the BMS fine-tuning its estimate of energy in your battery. Its easily shown by using a stats app or reading the CAN bus. The Tesla energy gauge is an energy gauge, not a guess-o-meter like other cars.

Driving to lower SoC and charging higher helps it make better estimates, as opposed to many shallow cycles of say 80 to 70% repeatedly.

Also, the energy graph predictions are based on a different number than the energy gauge miles because of some fudge factors (see: “energy buffer” and driving below dashboard zero).

The rated miles on the display tick down about 5% faster than energy graph IIRC. Each model car and trim has its own internal constant.

 

[AdamMacDon]

I find the kilometers display completely useless. I drive mostly in the city and admittedly I drive a bit more on the aggressive side, if I didn't care about performance I would have bought a Leaf or Bolt. Just like the KM's remaining in my Dodge Charger, I find it a completely inaccurate and pointless. Sometimes as much as losing 5km when driving 500 meters, and that's not going anywhere near full throttle and with a 50km average it still varies by up to 10x. I'd much rather have something like my gas gauge in my ICE vehicles. That way it isn't constantly bouncing up and down everywhere, and I can do my own math on realistic distance I can travel on a charge based on percentage and trip odometer. Same reason I always ignored "distance to empty" displays in my gas cars.

 

[N54TT]

Miles is a better indication of the batteries full capacity (which will degrade). at end of charge. That degradation can only be seen with miles and can’t be noticed if you are just looking at percentage at end of charge. But Percentage is a better/easier indication, as you drive, of how much left you have of the batteries full capacity. I like using miles when charging and percentage when driving. It’s a pain to keep switching so I just leave it on miles...unless I’m out on a road trip that requires multiple supercharges...then I’ll switch to percentage.

 

[cypho]

I wish there was an option to completely remove the battery gauge from the display until the charge drops below X miles/%.

I always start the day with 10x more range than I need. Why clutter the screen with information that serves no purpose other than to induce range anxiety.

 

[mknox]

I wish Tesla would show both side by side and do away with the toggle.

They should show both, but the miles/km should be from the Energy App estimate, not the silly linear scale that they currently use on the battery gauge which does no actual prediction of how far you can really go.

 

[Zelfiris]

My commute is short and I have been mainly using just percentage - so I know roughly when to charge. I try to charge it between 20% to 30%. I guess my primary concern has been the battery's health.

Now if I need to travel (not day to day short commute) then I'll change it to KM to keep an eye on the range left.

 

[jerry33]

They should show both, but the miles/km should be from the Energy App estimate, not the silly linear scale that they currently use on the battery gauge which does no actual prediction of how far you can really go.

AFAIK, the only really reliable way is to set a destination and look at what the Nav system tells you. Every other kind of measure only measures past behaviour. Kind of like the stock market charts.

 

[AlanSubie4Life]

the miles/km should be from the Energy App estimate

This estimate is also useless, unless you're talking about the number out of the Navigation estimate (which is the only useful predictor I'm aware of). The straight range estimator (not based on destination) is silly since it only involves the last 30 miles of driving, takes no account of hills or conditions, etc. I've never found it to be remotely accurate for an arbitrary drive. For example, my P3D+ currently shows 238 miles of estimated range with 254 rated miles, which is laughable (I'd make it about 195-205 miles max, depending on the type of driving assuming it is flat).

When I get home tonight, I suspect I will have about 237 rated miles, and the range estimate will be below 200 miles.

That estimator based on past driving works alright if you live somewhere perfectly flat and drive the same route every day. The results will be fairly consistent then. But any hills and it's just kind of silly.

 

[jerry33]

My commute is short and I have been mainly using just percentage - so I know roughly when to charge. I try to charge it between 20% to 30%. I guess my primary concern has been the battery's health.

Now if I need to travel (not day to day short commute) then I'll change it to KM to keep an eye on the range left.

Tesla recommends charging daily, not waiting until you are down. Waiting until 20% is not the way to do best battery health.

 

[darth_vad3r]

They should show both, but the miles/km should be from the Energy App estimate, not the silly linear scale that they currently use on the battery gauge which does no actual prediction of how far you can really go.

Which of the 6 different range predictions available from the energy app would you choose?

 

[qdeathstar]

percentage is more dramatic. Like, when you pull into a super charger at 9 percent your like “whoa that was close” instead of “gee, i still had 27 miles of range”...

 

[westernvine]

I'd love a different option:

• No number of any kind

I want it to be like an iPhone battery display... sure, there are options to show a percent or whatever, but why need it for daily charging and commutes, etc.? It'll still be visible like a progress bar, sort of, and go brown at 20%.

When navigating to a destination, maybe bring it back, so you have the option for road trips or to check on any degradation.

 

[darth_vad3r]

I'd love a different option:

• No number of any kind

I want it to be like an iPhone battery display... sure, there are options to show a percent or whatever, but why need it for daily charging and commutes, etc.? It'll still be visible like a progress bar, sort of, and go brown at 20%.

When navigating to a destination, maybe bring it back, so you have the option for road trips or to check on any degradation.

Good idea, except existing yellow instead of brown

They should let you “complicate” the display as much as you want with any or all (or none) of the following at the same time:
km, mi, %

 

[jerry33]

I'd love a different option:

• No number of any kind

I want it to be like an iPhone battery display... sure, there are options to show a percent or whatever, but why need it for daily charging and commutes, etc.? It'll still be visible like a progress bar, sort of, and go brown at 20%.

When navigating to a destination, maybe bring it back, so you have the option for road trips or to check on any degradation.

Since you plug in your car every day (or should), for most people it doesn't matter locally because they never get anywhere close to running out. On trip the Nav system's estimate and trip graph work just fine. I really don't see what all the fuss is about. The current display works just fine (although rated/typical range is a bit conservative).

 

[Xenius]

Typically percent. Less worry that way.

 

[derotam]

Ok ok time to throw more wood on the fire!

So for all those people who swear by using %....if you go to buy a used Tesla, are you just going to look at the % at full charge and see that it shows 100% and be like ok we are all good here...?