Oops, long ramble.
This NextEV EP9 not an effort to be sniffed at.
For ANY car, even non-road legal, a 7:05 around the Nordschleife is a serious matter. To even manage that in an LMP1 car would take a pretty committed driver.
The specs are promising. 1735 kg, 635kg of which a battery pack that lasts 265 miles. Considering the downforce focused aero design, I'd say that's around 90kWh if not more. So roughtly the same pack weight AND capacity as a Tesla 100 from 18650's. But, the peak output is nearly double.
Let's be clear, this car is lighter than a Rimac, and boasts yet unseen levels of dowforce. It makes the already legendary high DF Koenigsegg One:1 seem like the EV-range-anxiety specific body in comparison.
They're throwing around figures such as even 3 G's of (I suspect) cornering. One:1 claims 2.0 G's.
The acceleration figures are impressive also, but it seems the motors are either a bit rpm-specific, or as all other EV's, it suffers diminished power from (over)heating. With such massive aero and (for a supercar) decent total weight, 7:05 is somewhat disappointing. I doubt it has 1MW on tap in the last quarter of the lap. That would be beyond amazing. Of course we can't expect this startup to match the Porsche 918 ICE road legal record holder (6:58) for cornering speed, although the claimed 2.5-3's implies it should do so at least in fast corners.
What could Tesla do with their rumored new Roadster? Would the 2170 cells coming up suffice to take BEV supercars to the next levvel, beyond this EP9 and the Rimac?
Tesla seems to have established itself as an impossible to beat player when it comes to traction control off the line. Or, we don't fully understand yet how a heavier car generates traction to overcome its own added mass.
A ~150kg lighter pack from 2170's would still match the EP9 for range in a similar body. But such a ~90kWh pack of course "only" netts half the EP9's megawatt. Would Tesla need to also go 4-motor to get the best heat management? With smaller battery power, similarly big motors to the EP9 would not heat up too quickly. Or, lighter motors would suffice but heat up easily.
Or, would Tesla put in an additional high-(dis)charge pack of around 50-100kg, to produce short bursts closer to 1MW total, and enjoy really high regen under braking to achieve more for track use?
EP9 has a gearbox per wheel, to not only be quick off the line, but also bring top speeds over 200mph. With Tesla's currrent motors, you fell in a 20% lighter sports car, the same drivetrain could be easily geared 25-30% higher. It would still get off the line like today's P100DL, but have the revs to go way beyond the currrent 155mph/250kph. Without a gear box. But, heat WILL be an issue.
Appreciate that EP9 did a whole lap of the ring in a very impressive ICE hypercar worthy time. This is not done if after 2 minutes there is a dotted like at 100kW. A modern Tesla drivetrain in a lighter body simply doesn't manage 7:05. It would do a quick 0-60 and 1/4, but that's about it. Rimac has taken cooling very seriously, and worked years on developing that when they already had a working car. EP9 get's around the Nurburgring with what must have been never less than 300kW of "juice flow". Telemetry will likely stay a secret.
Does anyone know of cell technology on the market today that approaches Tesla's Wh/kg pack figures while offering more W/kg peak output? The 2170 cells are to optimize Wh/L (volume) probably, not get high peak power. To compare Koenigsegg Regera 4.7kWh pack puts out the same 500kW peak power as a Tesla P90DL. 20x greater power to capacity ratio. Although vastly lower Wh/kg, so you don't want a 100kWh pack from such cells, it would weigh as much as the projected Roadster as a whole. In an EP9 lap time killing Roadster, you'd not want more than 400-500kg in batteries, surely. It will be difficult enough to get the rest of the car done under 1500kg, let alone the 1000kg you want. Tesla has a reputation to uphold in crash safety, and that's a "heavy" design burden.
For a quick lap around the Nordschleife yardstick, 90kWh is by no means necessary but obviously welcome. If you manage to achieve 500kW avarage around the lap, after regen, in 7 minutes you spend 35kWh. I suspect such a 7-minute lap time can be achieved with a good chassis and aero with even less. Say a 500kW peak output that thanks to great motors and cooling is available most of the time, with good regen capability. Now of the total weight can be kept under 1500kg, the current breed of hypercars will be well under pressure.
A lot will depend on whether Tesla want a $200k Roadster or a $1M standard redefiner such as the Bugatti Veyron was, and the Koenigsegg One:1 is. At $200k, no choice, it has to get cheap batteries and even motors borrowed from the sedan and SUV. A fancy chassis would need to reduce weight A LOT, and additional cooling measure would keep the power more available through a timed run.
The key metric seems to be the continuous (and interval) power output from both the battery and the motors. Peak power is a party trick that doesn't even get you to 1/4 mile. P100DL is down to 450kW from 567kW or so before a 1/4 mile is over (10 seconds). In a longer track attack, will the dotted line allow for even 200kW? In a new generation Roadster this will not be "cool"(no pun intended) IMO. When you say there is a racey 500kW, it's should be down to a journeyman 200kW after a single short GP lap.
