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145 kw V2 Supercharging - Which software version?

145 kw V2 Supercharging - Which software version?

Which version includes this feature? I have a road trip coming up and would like to get access to higher speeds. I'm on 2019.5.15.

I requested a firmware update on the mobile app and it scheduled me for service in Kansas in 2 weeks (I'm in NJ). A chat with Tesla says I am currently up to date on software and will receive the new version when appropriate.

Thanks

Teslanene | 18. april 2019

I updated to the latest 8.5 and went to supercharge yesterday in Petaluma where there are videos of 145kw. I still couldn’t get close to 145km, 117km was the max.

elecfan2 | 18. april 2019

You'll find that Tesla and people here throw around the terms "released" when talking about new and unreleased features, but they're really just beta tests installed on a select few vehicles and people that do reviews in the media or YouTube. It'll get released someday to us regular folk, maybe a month or so, who knows.

stevehendler | 18. april 2019

Sounds like the feature isn't ready yet, especially considering it hasn't appeared in any release notes. Thanks for confirmation.

M3BlueGeorgia | 18. april 2019

Not much use anyway until Tesla have upgraded most of their V2 Superchargers to 145.

Once you get outside major urban cities, you generally won't need to share a paired Supercharger, so you'll see the 500mph charging.

Usual advice:
1) Charge a warm battery
2) Aim to charge when battery is between 15% and 20%
3) Try to make sure you aren't sharing a A/B pair with another car.
4) Avoid charging over 80%, and really avoid charging over 90%, unless taking a meal break. Its a lousy use of your time and of the Supercharger.

elecfan2 | 18. april 2019

You might be confusing V2 and V3, there aren't any public V3 chargers yet outside of a test installation and V2 will always be shared charging A & B stalls, this can't be fixed with a software update and will require the station to be upgraded to V3 before that will happen. All V2 superchargers should be able to support 145kW charging but since there isn't widespread software updates for the Model 3 to confirm this we'll just have to wait and see. Little information coming from Tesla officially.

Arif.K | 18. april 2019

Don't mean to hijack this conversation but I have a related question. How are these superchargers (V2, V3) able to charge faster when the 32amp onboard charger would be the ceiling.

elecfan2 | 18. april 2019

Superchargers directly charge the battery by bypassing the onboard charger.

Arif.K | 18. april 2019

Ah, interesting. I wonder what the tech is that allows that and why Tesla did not build that tech in the Wall charger they sell online.

elecfan2 | 18. april 2019

The wall "charger" is not a charger, that's why it's called a wall connector. It just provides AC current to the onboard charger, it also regulates the power delivered and tells your car how much current is available. This is similar to other connectors such as the J-1772 plug you see at public charging stations and home connectors like the Juice Box.

The way the supercharger works is they have a bank of "onboard chargers" from vehicles all stacked together in a nearby cabinet. They work together to simultaneously charge your battery directly using DC current.

Arif.K | 18. april 2019

I am guessing they don't need to do the AC to DC conversion, like it has to be done from your home circuit. If that's the case, it would be interesting if the DC energy from solar panels (via Tesla battery) could be directly fed to the Tesla M3 hence bypassing the inverter that converts it to AC.

Arif.K | 18. april 2019

Thanks for that explanation. I had submitted my response prior to reading your final comment.

elecfan2 | 18. april 2019

When you install the Tesla wall connector, you configure it with how much power your power line to it can handle like 24A or 40A or more. The portable connector that comes with the car is configured by selecting the proper "plug", and that plug will tell the connector what AC power and amperage is available. The are various plugs that you can buy from Tesla directly. I bought the 20A 120V plug that I use regularly, and it tells my car that I can draw 16A since it will only plug into a 20A 120V outlet. The 15A 120V plug already comes with the car and it tells the car that it can only draw 12A. Same thing with the NEMA 15-50 plug, it'll tell the car that you can draw 40A (actually it's 32A as the portable connector can't goto 40A) (Also note all allowable amps that can be drawn are 80% of the maximum when talking about continuous draw per electrical code). The portable connector is limited to 32A, but the onboard charger can handle up to 48A for the long range Model 3 variants when connected to a properly configured and sized Tesla wall connector, for the lesser battery sizes (standard, plus, mid) it's 32A.

elecfan2 | 18. april 2019

Well the power company provides AC current only. The wall connector or portable connector just takes the AC current from the wall or panel, puts in some information by handshaking with the car to tell it "hey, we've got up to 60A, what do you want?", and then lets the juice flow if the handshaking works out okay.

Your onboard charger converts from AC to DC so that it can charge the battery with DC current. At a supercharger, the bank of chargers convert the AC current from the nearby transformer to DC and then funnel that into your car's battery (bypassing the onboard charger).

elecfan2 | 18. april 2019

Yeah I wish they'd do direct DC charging from the powerwall to the car, but apparently that's not how it's done. Not sure why, maybe the efficiencies are negated by requiring thicker cables to the car. Running high amperage over cables using DC requires thicker cables, that's why V3 superchargers will have water cooled cables. Other DC quick chargers out there are using water cooled cables at high charge rates too.

Arif.K | 18. april 2019

I have solar panels and I see that this process is a terrible waste of energy by converting back and forth. The solar panels generate DC which my inverter converts to AC and feeds it back to the grid. There is obviously x loss in that conversion. I have not read the specs of the Tesla powerwall but if it stores the energy in DC straight from the panels, it would be interesting if it could feed that DC energy straight to the Tesla. So no conversion to AC and no loss.

Tronguy | 18. april 2019

@Arif.K: I'll make this is short as I can. Ta-Da: I'm a real, no kidding electronics engineer. No, I haven't broken down a Tesla into teeny little bits to figure out how it goes (but, never fear, if I did want to do that, I could). But the broad strokes of what's going on is pretty clear.
You'll note that the TWC and the mobile adapter take in AC and hand it off to the car. The car's battery is around 350VDC. This is nothing like a rectified 120 VAC or 250 VAC that comes in off of a potential wall socket.
So, the modern way to handle stuff like this is to first, rectify the AC voltage and, second, run it through a DC-DC converter. Rectification is pretty efficient; one can get to a DC voltage without much trouble with synchronous FETs with efficiencies in the 95%+ range. I wouldn't be surprised if it was 98%+.
Next: One feeds the rectified DC into a couple-three mongo transistors that have the primary of a transformer. The transistors flip on and off in pairs at, usually, some fixed frequency, pushing current back and forth through the primary of the transformer. The time the transistors are left "on" is usually variable and set by a switcher controller, whose programming, I'm sure, is something to behold.
The secondary of the transformer has more synchronous rectifiers that generates a mongo DC voltage that is used to charge the battery. That voltage is set to whatever the Tesla battery potential might be.
Increase the time the transistors are left on: More current into the battery. Decrease it: Less current. But, and this is the point, everything has to go through those switching transistors and the transformer.
There are limits in everything. First off, big-ass transistors that can switch 100's of amps are physically huge, have losses, and have to be attached to big heat sinks. Further, the bigger the transistors are, the bigger their gate-source capacitance, making it more and more difficult to make them switch fast. So, really big transistors that can do 100's of amps at these voltages are difficult or impossible to switch, say, at 2 MHz.
Next: That transformer. Said transformer consists of coils of wire or the equivalent embedded in some (usually) ferretic material. The ferretic material takes the magnetic field generated by the coil and, pretty much, makes a magnetic current that's much larger than, say, what that coil can do in air. Which is good because this means that the transformer is miniaturized over, say, an air-coil transformer. Big magnetic currents can carry more power, so this is all to the good. However, try to make too much magnetic current in a given ferretic core and said core will _saturate_. Take my word for it, that's a very bad thing to happen to a transformer and can cause a Musk-style Rapid Unscheduled Disassembly event if it occurs. (Unless you mean that to happen: See, "Magamps").
So, there's limits, here, too. The higher in frequency one switches the transformer at, the smaller it can be, but, see transistor switching frequencies, above. Further, making a 10 kg transformer (more material, less likelihood of saturation) has its own problems, since now one needs more wire, and lots of wire is antithetical to high switching frequencies more problematic, and so on. And you don't want to spend zillions, or carry the weight around, of a really high-power AC to DC converter. (Back at work, I've got a pet one I use to power telco gear. It cost around 20 grand, takes in 400 VAC, and puts out 50V at 15 kW, and was cheap at the price at the time.)
Now, a Supercharger has a high voltage present, bigger than the 350V in the Tesla. But a Buck Converter doesn't need to switch at really high frequencies, needs (pretty much) one big-ass coil, a transistor to ground, one to the battery, and an appropriate controller. Not nearly as complicated as a DC-DC converter with a transformer, and there it is.

Tronguy | 18. april 2019

@ArifK: Regarding Solar Panels. I got them, too. Interestingly, modern panel systems have DC-DC converters on each panel. The input side of each converter is hooked to the panel and the voltage and current adjusted until the power extracted from the panel is maximized. The output sides of the DC-DC converters across a string of panels are connected in series. The collection of a bunch of these is rigged so the voltage across a string is 300V DC. Since this batch of power module outputs are connected in series, the current through them is the same; however, a panel that happens to be generating more power than the other panels gets adjusted so its output voltage is greater than the output voltage of the other panels in the string, but the total is still 300 VDC. Panels that are generating less power get less voltage across them.
A single string can be connected in parallel with other strings doing the same thing and, finally, the whole conglomeration is connected to an inverter; which, so long as the sun is up, takes in 300V at whatever current the pile of these panels is generating and converts same to AC.
The cute thing about the Powerwall is that it (a) has the inverter built in and (b) the battery is at 300V, too.
Now: There's a California standard for inverters out there that I read through back when my system got put in. The standard describes how to measure the efficiency of the inverter. Interestingly, what with coils, switching transistors, and all, these things get efficiencies in the 98% range.
So, what with my 9 kW of panels on the roof, how come I never get more than 7800 W delivered from the panels? Answer: In my case, I don't have those DC-DC converters on each panel, so the weak panel in a chain reduces the power of the other panels, even more so when the strings are in parallel with other strings of panels.
But the one, big thing that reduces the overall efficiency: Getting the power down off the roof. The I*I*R drop on the wires loses about 10%.
As far as getting the panels to drive the car: possible, but expensive, unless Tesla or somebody else starts mass-producing supercharger hardware. And, don't forget: That 300V is dead dangerous.

TeslaTap.com | 18. april 2019

I'll add to Trongus good description - The battery requires a very specific voltage that varies as the SOC reaches 100%. If you connected some random DC source (i.e. solar cells) to the battey, you would either:

1) Melt the solar panels and perhaps catch them on fire if the Solar voltage was below the battery voltage (i.e. you're putting power into the panels, something they are not designed for). Ok, they are likely fused to prevent this, but something you'd not want to try.

2) If the solar voltage was above the desired battery voltage (and you have enough current) you would destroy the battery pack (and it would likely catch the cells on fire).

The likelihood of the solar cell output voltage matched what the needed battery voltage is zero. If for one fraction of a second it was correct, it would be wrong seconds later as the battery charges. Should a cloud go by the solar array, problem 1 would immediately occur too. Bad on so many levels.

Best is to convert the solar power to AC, and then use the car's AC charger to convert it to the proper voltage/current needed to safely charge the battery.

Arif.K | 18. april 2019

@Tronguy. Thanks for the detailed explanation. I won't pretend that I understood all of it but I think I understand the gist.

About your solar installation. From your description of how shading on panel can adversely effect the entire array. I believe you are describing a string array. I have power optimizers connected to each panel. They are DC-DC converters. And the energy from all these power optimizers is then fed to the central inverter that converts to AC.

@TeslaTap, I was not suggesting plugging the Tesla directly to the panels with its fluctuating energy generation. I was just curious that if a battery such as the powerwall can store DC, if it were able to output DC straight to the car battery, would we essentially skip the car's onboard charger and hence bypass the 32amp charge limit for AC?

elecfan2 | 18. april 2019

Remember the 32A limit you are referring to is probably related to the portable connector that comes with the car. The Model 3 Long Range battery can charge at up to 48A with the onboard charger (like Model S and X current vehicles are able to do) coupled with the Tesla Wall Connector (TWC), while the lesser batteries are limited to 32A onboard charger even with the TWC.

Some older Model S (not sure if the X had this) models had the option in the past for dual chargers at 80A and then one option at 72A and could charge really fast though that isn't offered anymore. There are some private superchargers out there but they are limited to 72A charging.