Welcome to Tesla Motors Club
Discuss Tesla's Model S, Model 3, Model X, Model Y, Cybertruck, Roadster and More.
Register

Slower supercharging on Model 3

This site may earn commission on affiliate links.
That doesn't explain why larger battery Model 3 is also slower than 70 Model S.

Physics. To sustain high charge rates, the most important factor is heat transfer (away from the cell). The larger cells in the Model3 make it harder to evacuate heat internally plus the cooling system may be less performant in the 3 (to save costs, also Elon has been quite explicit, everything about the S/X is better than the corresponding element on the 3).

There is a reason Tesla is not rushing to put the 2170 into the S/X despite them being (a lot!) cheaper.
 
Instead Tesla can just do 100/120k mile warranties then just ignore that when a battery fails at 130k and charge just a trade in fee of say $1000 for labor. They can then repair the old battery and use it in another car that fails after 130k.

I'm not sure repairing batteries by hand would be economical. Although it does make me wonder whether there's a good economical way to refurbish packs - aka a machine that opens up a pack, tests each cell, swaps out each dead cell for a new one, and seals it back up. So the packs could be sold aftermarket for a small fraction the cost of new ones, providing people with old cars an economic option for replacement. How much labour is involved in a swap?
 
If you check out Bjørns video of roadtrip with Ampera/Bolt it shows DC charging speed. Looks like car is limited by how many amps the charger can put out untill the car orders tapering.

Maximum achived 45 kw, doesent say where but likely just before tapering starts on 55% ish SOC. Charger is 50kw 125A.
Bjørn makes a detour for a rare 80kw charger only to find he cant charge there as it`s offline and he dosent have access.

25% SOC = 41 kw
60% SOC = 40 kw
70% SOC = 23 kw

If you arrive with 0% and charge to 60% you will get 40kw charging speed on average and it will take you just shy of 1h.

Compared to any Tesla this is really bad.
For DCFC trips it mostly comes down to miles per minute charge rate.

Jeff has reported 60 kWh to cover 190 miles at 70 mph in a Bolt, for a consumption rate of 3.16 miles a kWh
It would be a poor idea to plan a trip based on arrivals at charging stations with less than 10% SoC, and charging in the taper zone increases charging time ~ two-fold so a Bolt is at its best collecting 30 kWh for 45 minutes every 80 minutes (95 miles) of driving after the start charge is used.

I'm not sure about the Model 3 yet
Perhaps 4 miles a kWh at 70 mph, and perhaps as low as 50 kW or as high as 70 kW charge rates and ?? tapering after 65%
So somewhere in the range of 20-30 minutes charge every 110 miles.

This will be relevant when CCS exists where you want to go. In my case, for now no where.
 
Last edited:
Certainly there are variables, but one you take them Into account for most supercharger legs, deliberately arriving with 20 miles is absolutely not risky.
"Absolutely not risky"? Do you have weather information readily available with wind direction and velocity for the next 100 miles of your trip? If rain is imminent, do you know how much and over what portion of your next leg?
I don't. Even Tesla trip charge predictor graph shows such low rated miles levels as risky.
 
"Absolutely not risky"? Do you have weather information readily available with wind directions for the next 100 miles of your trip? If rain is imminent, do you know how much and over what portion of your next leg?
I don't. Even Tesla trip charge predictor graph shows such low rated miles levels as risky.
I wouldn't target less than 20 miles at end of trip, unless coming home from a trip I do frequently. However, lowering speed is nearly always the magic solution.
 
  • Like
Reactions: transpondster
"Absolutely not risky"? Do you have weather information readily available with wind directions for the next 100 miles of your trip? If rain is imminent, do you know how much and over what portion of your next leg?
I don't. Even Tesla trip charge predictor graph shows such low rated miles levels as risky.

My range calculator that I made almost a decade ago did ;) It involved realtime weather forecasts, including scaling weather for changes with altitude relative to the stations that the forecasts were for. And when you wanted to plan a trip for further out than that, it used historic climatological data.
 
Although absolutely disappointing in itself, these rates are slightly better than I feared based on the released/leaked Model 3 charging picture where the LR version was getting 70.6kW after more than 7 minutes at near optimum SOC.
The likely pretty small 52-55kWh SR battery, with the slower 2170 form factor may in fact make alternative charging stations a very viable option to SR owners. They may well be better on route for them, and going to the SC will not save them real time. Only cost, if that. If a SC is in the middle of nowhere vs a ChaDeMo at prime location next to a big mall, guess which one gets the business? This may well aleviate the stress on the SC network for what the SR cars are concerned.

These slow rates make Model 3 lose against Model S and likely also X in a road trip race at legal speeds. As they should. And it's all thanks to the 99% focus on cost/kWh, the 1% on durability+safety+practiclity.

For Model S and X, bound to get on the slow cell bandwagon, the only way it would not be a downgrade, would be for a bigger pack to be used. Say, an 85-90kWh pack from 2170's costs less than a 75kWh 18650 pack, Tesla could decide to change it over, and the owner would not suffer a charge speed loss. The capacity left on the table helps Tesla out with durability and the owner with charge speed (low and high SOC are slow). Could the 85kWh packs for 75 S/X cars be about this...? Similar to 60(75) packs before, the extra range could be unlocked at a price. Tesla created value without added cost, likely even a saving.
The higher energy density of 2170's should allow for the 100 to be upgraded to 120, with not loss of chargings speed, even a slight improvement.

Where that leaves Tesla for the future though, its competitors looking to take the fast charging road accepting higher cell costs while Tesla committed billions to make their cheap as possible and consequently slow...no idea here. Their upcoming faster chargers are only good for Semi trucks witth huge batteries, or supplying say 6 or 8 stalls from one charger, a cost measure more than a service one.

I was expecting the Model 3 to charge quicker than todays Model S, due to improvements in cell chemistry. Remember the 350kW charging is childs play tweet from Elon? If 350kW is childs play, than what is this?
It was always about density, not speed. Some high profile vloggers impplied about some secret breakthrough, but then it's still secret today.

That doesn't explain why larger battery Model 3 is also slower than 70 Model S.
The large form factor of the new cells reduces wall surface vs content. Heat is dissipated slower, cells can't be pushed as hard. You have lower cost by using less metal and rolling up frewer internals, and soldering fewer cells together to make a pack, but charging will be slower.
 
The argument that the battery is the most expensive part of the car is losing ground.
50/55kWh at a cost falling from $200/kWh towards half of that as GF1 builds momentum, means that the cars delivered afted the reservation holder will pay $35K+ for a car with a €5,000-6,000 battery in it. 40.9% more range costs you $9,000.

One aspect with the small and slow charging batteries in Model 3, both versions, is for people who can't home charge. If you need to charge twice a week and basically waste your time if it's not near a store you frequent anyway, it's nice to have the bigger battery that makes it roughly twice in 3 weeks. If saves you time in your life. For those buyers, it takes a green heart to coose the costly Model 3 over the competition.
And really, as Model 3 reaches new owners, the percentage of Teslas that will see zero home charging is going to spike up while at the same time spiking Supercharger attendance. Especially with so make 3's being delivered over the first 1.5 years.
 
Although absolutely disappointing in itself, these rates are slightly better than I feared based on the released/leaked Model 3 charging picture where the LR version was getting 70.6kW after more than 7 minutes at near optimum SOC.
If 70 kW is the peak SC rate for the larger battery Model 3 then we are probably looking at ~ 50 kW for the base version. Fortunate for us the highway efficiency is good, or this would be a less than happy state of affairs. This seems to point towards 3.8 miles per minute charge rate in the base Model 3 at low SoC on the combined EPA drive cycle. Or about 30 minutes when SC jumping.
 
Last edited:
My range calculator that I made almost a decade ago did ;) It involved realtime weather forecasts, including scaling weather for changes with altitude relative to the stations that the forecasts were for. And when you wanted to plan a trip for further out than that, it used historic climatological data.
I remember posts about that. Yours was a prodigious amount of work that was all the more valuable at a time when there weren't superchargers every 120 miles in most of the country. Do you still use it regularly, or just when charging opportunities are sparse?
 
If 70 kW is the peak SC rate for the larger battery Model 3 then we are probably looking at ~ 50 kW for the base version. Fortunate for us the highway efficiency is good, or this would be a less than happy state of affairs. This seems to point towards 3.8 miles per minute charge rate in the base Model 3 at low SoC on the combined EPA drive cycle. Or about 30 minutes when SC jumping.
It's been published as charge to be gained in 30 minutes, likely at ideal SOC. 130 and 170 miles respectively over 30 minutes. So an ideal average charge rate of 260 and 340mph. Using 236Wh/mi as a fair estimate, that's 61kW and 80kW. True peak charge speed may be a bit above that.
The long range car kind of needs Superchargers and fast CCS 100kW chargers, the standard car can divert to various DC chargers that offer some 50-60kW and not really lose time. Sometimes maybe take a shorter route because of it, catching back up some of the time lost.
 
Judging by the time of day I reserved, I was about 75,000th in line overall globally, behind international orders, employees, and owners.


When you factor in ownership, employee status, and geography, I feel pretty fortunate that I might be able to get a loaded RWD by the end of this year.

Now that some people are cancelling, my odds of that are improving.

But man.......that slow supercharging.....whew....not sure what to do about that.........
 
  • Funny
  • Like
Reactions: S3XY and Cloxxki
But man.......that slow supercharging.....whew....not sure what to do about that.........
It's not that much slower than a base Model S, is it? You have to look at the miles added per minute. And really you start with range similar to an S100, so you will not need to supercharge as often as an S75 owner, presuming a home/destination charger to start off your drive.
I can't find 30 minute charge data for S75 for some reason, but assuming 90kWh average over an ideal 30 minutes, that's 45kWh or (~280Wh/mi?) 160 miles. So 3LR at 170 miles in 30 minutes is not significantly slower charging than S75. Even if S75 average 100kW, it's a wash. In this metric, Model 3 is a pretty good deal. Due to all the brand hype, and whispers of new Superchargers, of course we were right to hope for more.
 
It's not that much slower than a base Model S, is it? You have to look at the miles added per minute. And really you start with range similar to an S100, so you will not need to supercharge as often as an S75 owner, presuming a home/destination charger to start off your drive.
I can't find 30 minute charge data for S75 for some reason, but assuming 90kWh average over an ideal 30 minutes, that's 45kWh or (~280Wh/mi?) 160 miles. So 3LR at 170 miles in 30 minutes is not significantly slower charging than S75. Even if S75 average 100kW, it's a wash. In this metric, Model 3 is a pretty good deal. Due to all the brand hype, and whispers of new Superchargers, of course we were right to hope for more.



Ssshhhh.... Play along.

I'm really fine with it. But some people might get spooked and cancel.
 
30 minutes for 170 miles of range incredibly fast. No other manufacturer can come remotely close to this. FWIW, there are more cells in a 18650 pack so the difference in taper makes sense to me.

Whatever the reason, we all need to drop this notion that a reduced charging rate is going to discourage locals. They're building a SC in Honolulu specifically for locals. The same goes for SF, LA and other metro areas. There's been a fundamental change in the purpose of SC stations.

Tesla wants Supercharging to be done as quickly as possible so drivers don't have to wait. It makes no sense to punish all of your customers in an attempt to discourage someone who is paying to charge. Let's be realistic - anyone willing to drive to a SC station so they can pay for 30 minutes of charging is willing to drive there so they can pay for 40 minutes of charging.