Elon's "Step Change in SC Technology"

[lolachampcar]

Anyone heard anything about the step change in super charger technology that Elon mentioned during the conference call today. They are already charging at 1C. Any word on the capacity of the existing chargers as I would assume the hardware that is going in today has the current capacity to accommodate the "step change" once the system engineering and testing is done.

 

[strangethingintheland]

Anyone heard anything about the step change in super charger technology that Elon mentioned during the conference call today. They are already charging at 1C. Any word on the capacity of the existing chargers as I would assume the hardware that is going in today has the current capacity to accommodate the "step change" once the system engineering and testing is done.

I had simply assumed it was related to the previous reference he made (to up the charging from 90kV to 120kV) at the time of the original SC announcement.

 

[CapitalistOppressor]

I had simply assumed it was related to the previous reference he made (to up the charging from 90kV to 120kV) at the time of the original SC announcement.

That's what I assume. It has been mentioned several times, including in the Q3 conference call if I recall. Never any details, but the current SuperChargers have a 120kWh head apparently, which they split between two vehicles (90/30). Seems to me like there's no reason it couldn't output 120kWh to a single vehicle if they get the kinks worked out.

For that matter, the initial discussions about the Model S seemed to describe a faster charging system then the current SuperChargers. Might be they had some bugs they wanted to work out, so they deployed something slightly less capable, and are now ready to implement the original plan.

 

[jkirkebo]

That's what I assume. It has been mentioned several times, including in the Q3 conference call if I recall. Never any details, but the current SuperChargers have a 120kWh head apparently, which they split between two vehicles (90/30). Seems to me like there's no reason it couldn't output 120kWh to a single vehicle if they get the kinks worked out.

Well, to charge the Model S at 120kW the connector would have to sustain a current of 340A. Can it really tolerate that ?

The other option is to charge at 255A like today but up the voltage from 365V nominal to 485V nominal. This means a new battery layout, and would thus be a more likely feature for the Model X.

And I think the 120kW split is dynamic. I'm quite sure it can do 60/60 when the current ramps down on the primary vehicle, but it would be nice if it could do 80/40, 70/50 etc.

 

[apacheguy]

The other option is to charge at 255A like today but up the voltage from 365V nominal to 485V nominal. This means a new battery layout, and would thus be a more likely feature for the Model X.

Can you explain what you mean by a new battery layout? The way I understand it, the Model X will use the same batteries as Model S (60 and 85 kw versions).

 

[GSP]

The step change that is needed would be $25k Supercharger installations, instead of $250k. Something to lower energy and demand charges would be helpful also.

The only problem with the existing Superchargers is that there are not enough of them yet.

GSP

 

[strider]

Can you explain what you mean by a new battery layout? The way I understand it, the Model X will use the same batteries as Model S (60 and 85 kw versions).

He means changing the combination of series vs parallel wiring of cells to give a different electrical layout. Parallel wiring (+ ends all wired together, - sides all wired together) yields the same voltage but higher current. Series (+ of one cell connected to - of the next) yields the same current but higher voltage. Physical layout remains the same.

 

[jkirkebo]

He means changing the combination of series vs parallel wiring of cells to give a different electrical layout. Parallel wiring (+ ends all wired together, - sides all wired together) yields the same voltage but higher current. Series (+ of one cell connected to - of the next) yields the same current but higher voltage. Physical layout remains the same.

Yep. The Model S battery has something around 98 cells in series, since the max voltage is somewhere around 405V as displayed when SuperCharging. Upping this to for example 130 cells in series will give a max voltage of about 540V and increase SC charging speed by around 33%, equaling about 120kW.

This depends on the SuperCharger being able to output 540V though. Also the cable&connector must be rated for that much.

Limiting to 500V means around 120 cells in series and a charging power of ~110kW max.

 

[lolachampcar]

It would seem difficult to then manage two different pack voltages out in the wild. This would also mean that the increase in SC performance would only apply to certain vehicles. I got the impression from the comments that it would be a good thing for everyone which would point more towards allowing the full 120kw to go to existing cars via increase current.

 

[apacheguy]

It would seem difficult to then manage two different pack voltages out in the wild. This would also mean that the increase in SC performance would only apply to certain vehicles. I got the impression from the comments that it would be a good thing for everyone which would point more towards allowing the full 120kw to go to existing cars via increase current.

I have the same impression. I'm fairly confident the "step" 120 kw charging would apply to the current Model S. After all, this was Elon's plan from the beginning, per his announcement at the Hawthorne unveiling. It just doesn't make sense for them not to incorporate this tech into the Model S, especially when it is already there, it just has to be improved.

So, granted, either the amps or the volts are going to have to jump to get to 120, but I don't see why they would change the battery
layout for the Model X so that has me thinking that it will work on our cars as well.

 

[Todd Burch]

I was thinking that Tesla limited Superchargers to 90 kW in software so that they could do longer-term battery testing at 120 kW. Production started before the long-term testing was complete, and now Elon believes there is enough data to show that 120 kW is not overly detrimental to battery life. So I suspect this will be mostly be a software upgrade. Not sure if the existing Superchargers already have the hardware to support 120 kW.

 

[Bipo]

Not sure if the existing Superchargers already have the hardware to support 120 kW.

Maximum current supported by the plug may be the problem... I don't know if it can deal with more than 240 A.