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Discussion Starter #1 (Edited)
It's June, and once again time for the Pikes Peak International Hillclimb. In the last 5 to 10 years, electric vehicles--both in the automobile and motorcycle classes--have gone from being a non-entity to dominating the race. Last year, of course, Volkswagen spent a small fortune to make the ultimate Pikes Peak race car--electric, of course. Their efforts paid off when they beat the all time record by a significant margin.

This year, there has been less talk about Pikes Peak EVs. But when the competitor list came out in January, one of the entries was tantalizingly titled "2019 Palatov D2EV". But there were not any details available beyond this.

We can now reveal a little more about this entry. This entry is being done by Borg Warner subsidiary Cascadia Motion (formerly Rinehart Motion Systems and AM Racing). Cascadia is supplying motors, inverters and systems integration. Our own Frodus, now an employee at Cascadia, has been taking the lead on integration over the past month. The company I work for, EVDrive, has also contributed significantly. The car itself was designed and built by local (Portland) race car builder Palatov Motorsport, which has made several (gas powered) Pikes Peaks cars in recent years.

I can't give out any specific numbers, but the power to weight ratio of this thing is mind blowing. At these power levels, it all comes down to putting it in a package that can be tamed, and piloting it by a driver with the skill and courage to push it to the limits. To that end, Cascadia and Palatov have tapped Greg Tracy, himself a multiple champion at Pikes Peak and a professional stunt driver who has driven for Hollywood block busters such as The Fast and The Furious and the Bourne movies.

Here is a little teaser. The main event is in ten days.


https://youtu.be/Klydsui19p8
 

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I hope after the event there is more technical information about the car. It appears to have the expected dual-core HVH motor, but that's about all that is visible in the teaser. For instance, AWD became popular at Pike's Peak long ago, but the gravel is all gone so I don't know if that's still required for winning performance.
 

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Hi Brian,

Dennis Palatov has disclosed it publicly, so I can say it here: The car is, in fact, AWD.
Thanks. The Palatov website features blogs and some other information for earlier Pikes Peak cars, but not this one. Perhaps some day there will be some 2019 information.
 

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Discussion Starter #8
Thanks. The Palatov website features blogs and some other information for earlier Pikes Peak cars, but not this one. Perhaps some day there will be some 2019 information.
He actually does have a blog for this one:

http://dpcars.net/d2x/index.htm

He called it D2X when he started because he wasn't ready to reveal it was EV. But there is actually quite a bit of information there, plus lots of cool pictures and videos.

Edit: The 2019 he begins talking about on page 2.
 

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He actually does have a blog for this one:

http://dpcars.net/d2x/index.htm
Ah, thanks.... the DP Cars website, not the Palatov Motorsport website (where I found those other Pike's Peak entries).

He called it D2X when he started because he wasn't ready to reveal it was EV. But there is actually quite a bit of information there, plus lots of cool pictures and videos.

Edit: The 2019 he begins talking about on page 2.
The Palatov site for the D5 (a development of the D2) vaguely talks about an EV option, and electric variants of other models have been the subject of blogs and product pages since 2010. The vehicle is designed as a traditional race car, with the long-established mid-rear longitudinal engine, and the electric version just replaces the engine with a motor; it's not a new design. It's the electric and AWD variant of the latest generation of the D2. There's nothing wrong with that - when you have a winning formula you don't change too much - but it's not a path to interesting design.

In the D2 section of the DP Cars site, the new car being electric was mentioned at the beginning of page 2, but there's no further information on that page. Most of the way down page 2, a photo appears with a front final drive unit and a teaser comment about the "special build", showing that it has a typical AWD system; the AWD is new for this platform, but there's nothing specifically EV so far, and page 3 shows that they are still building LS-engine cars of this platform in the new generation.

On page 3 they do show an amusing generator set (to be complete by partners, presumably Cascadia), powered by a GSXR1000 engine. I get the novelty value, and the desire for a compact unit, but it seems like a way to make a zero-emission race vehicle as dirty as a typical-gas engined car; it doesn't use a clean or efficient engine for the stationary unit.

The closest this all gets to technical specs (other than acceleration data) is buried in the discussion of the tow van replacement, which notes that "this year's Pikes Peak car is heavier than what we've built in the past". That's typical of racing vehicles, which are only clearly described after they are museum pieces.

There is eventually a photo of the rear of the car, and there was that photo of the front drive components; between them they contain essentially the sum total of all design information available:

This appears to show the dual-core HVH/AMR motor flanked by battery packs. The packs sit in what are presumably normally aero tunnels, leaving the fancy rocker rear suspension holding the spring/shock units out of the non-existent airflow. :rolleyes: The usual Quaife, Porsche, or whatever transaxle is replaced by a simple bevel-gear final drive, and shaft runs up the middle to another final drive at the front.

The only technically interesting part is how the AWD is done. This is just a guess based on the photos, but it looks like front drive comes off the front of the dual motor assembly, and rear drive off the rear. There are a range of possible configurations:
  • this could be a dual-core motor with output taken off of each end, driving shafts to both axles at the same speed;
  • this could be a dual-core motor with solid drive to the rear and drive to the front through some sort of clutch (over-running, controlled friction, or even viscous);
  • this could be a dual-core motor with a centre differential; or,
  • what appears to be a dual-core motor could be separate front and rear motors, despite the common housing (unlikely because the relative front and rear power levels would not be appropriate).
There is presumably reduction gearing other than in the final drives, although speed is so high that perhaps the final ring-and-pinion sets are enough. If one reduction drive is shared between front and rear, it could be mounted at either end of the motor (presumably the rear), and the reduced output sent back through the motor's hollow shaft.

If they are driving both axles solidly at the same speed, or just letting the front over-run the rear for corners and powering when the rear slips enough, this is likely the result of their Pikes Peak experience... that with enough power that the car is usually drifting, so more sophisticated front to rear power distribution is unnecessary.

I'm sure the car will do well. It will be interesting to see how it works, and what the design really is.
 

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Discussion Starter #11
The only technically interesting part is how the AWD is done. This is just a guess based on the photos, but it looks like front drive comes off the front of the dual motor assembly, and rear drive off the rear. There are a range of possible configurations:
  • this could be a dual-core motor with output taken off of each end, driving shafts to both axles at the same speed;
  • this could be a dual-core motor with solid drive to the rear and drive to the front through some sort of clutch (over-running, controlled friction, or even viscous);
  • this could be a dual-core motor with a centre differential; or,
  • what appears to be a dual-core motor could be separate front and rear motors, despite the common housing (unlikely because the relative front and rear power levels would not be appropriate).
There is presumably reduction gearing other than in the final drives, although speed is so high that perhaps the final ring-and-pinion sets are enough. If one reduction drive is shared between front and rear, it could be mounted at either end of the motor (presumably the rear), and the reduced output sent back through the motor's hollow shaft.

If they are driving both axles solidly at the same speed, or just letting the front over-run the rear for corners and powering when the rear slips enough, this is likely the result of their Pikes Peak experience... that with enough power that the car is usually drifting, so more sophisticated front to rear power distribution is unnecessary.

I'm sure the car will do well. It will be interesting to see how it works, and what the design really is.
If you watch the teaser in the first post very carefully you may find clues that suggest a different solution...
 

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If you watch the teaser in the first post very carefully you may find clues that suggest a different solution...
I had fast-forwarded and skipped through it, and saw nothing of value. So I watched it again, complete with audio, and found it to be the usual egotist's test of my patience ("I'm a cowboy and I'm gonna ride a big bull"... yeah, there's bull there all right ;)), but I did see that at 0:36 it appears to have separate front and rear motors mounted in-line (nearly the two-motor option in my list, but the rear motor is itself a dual-core). That goes with the three inverters (for three cores) suggested by labels for one side (negative) of the DC link cable connections (at 0:39). Thanks for the tip; I had skimmed the video too quickly and missed these details. :) In hindsight, the motor detail is sort of visible in the photo shown in my earlier post, but that photo (from the DP Cars site) is much lower resolution and blocked by a frame tube, so I have an excuse... :D

Assuming that these are separate front and rear motors (not just three cores in tandem), this is the most capable of the alternatives which I listed, providing control of front to rear power distribution without resorting to friction devices by powering front and rear with separate motors. Of course we know from the images that it uses a single (although dual-core) motor for the rear, and a single motor for the front, so it depends on conventional axle differentials.

I realize that the teaser video is a promotional piece, not intended to convey information.

So here are the two video frames which convey all of the technical information in the teaser:
 

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Correct. Here is the general layout...
Now that's a good teaser! :)

First, some background:
In sports racing classes, one requirement of the rules is typically to have a passenger seat, or at least a space that could be seat, even it if had no seat and was unusable (fire extinguishers are routinely mounted in that space); it was originally part of a pretense that these were modified production cars. The earlier Palatov DP1 had the engine on one side (no possibility of a passenger seat), but the DP2 has a passenger seat space... not so much for race rules (unless but because it is available in a version with a second seat, and even a potentially streetable version.

The battery pack appears to extend forward on the right-hand side into the passenger seat space, with two of three approximately equal packs on the right side and only one on the left. This makes perfect sense for the racing car, provides more space for the battery pack, improves front to rear balance (it doesn't need to be so rear-heavy), and improves side to side balance (counteracting the offset driver). It also ties into a blog comment about asymmetric airflow in this vehicle, since there is presumably a cooler on the left side for which there is no equivalent on the right side.


It also appears that there is no reduction gearbox between the rear motor and the rear final drive; the front is not so clearly shown but I'll guess that it has no reduction box, either. Apparently either the top speed is so high that the reduction available in the final drive is suitable (a record-setting pace averages over 90 mph, with the peak much higher), or it is close enough that the extra weight and bulk (and slight transmission loss) of reduction gearing was not justified. Since I don't recognize the final drive case, I have no idea what gear set ratios may be available for it.
 

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Discussion Starter #15 (Edited)
Palatov has now posted images of the battery we at EVDrive built for this car, so I can share them here. This is the greatest battery we have ever made, exceeding the 315 kWh one we made for the original Nikola Motor prototype semi truck. It's very compact, liquid cooled, with an extremely robust interconnect system (the entirety of the interconnects add less than 2% resistance beyond that of the cells themselves). Apart from dragstrip packs that drain in less than a minute, this may be the most powerful battery that has ever gone into a car. We are very proud of it.











Edit: some specs: Just under 80kWh, 840V top off voltage, and 1800A peak (30s)
 

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Nice; looks tidy and functional. :)

Can you share the cell format (cylindrical or pouch), or anything about the configuration (presumably over 200 cells in series, presumably at least two cells in parallel at the lowest level)? How about the cooling configuration: cold plate under the stack (like most current EVs with pouch cells and the Rivian prototypes), cooling plates between cells (like a GM Volt), cooling tubes between cells (like a Tesla)...
Obviously, I understand that available information will be limited.

The top-view drawing indicated that the battery pack extended into the right-hand seat area, but the photos show only packs behind the seats. Did I misinterpret the earlier drawing, or is a third pack section just not in the photos? Now that I compare the photos to the drawing, I also see that the battery packs flanking the motor are substantially longer than the blue boxes which I assumed to be battery packs in the drawing. Pack access is facilitated by bolt-in rear upper structure, but there doesn't appear to be any accommodations of this sort for the seat area.
 

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Discussion Starter #17
The three blue boxes are actually the three PM250DZ inverters. The battery boxes are in fact non symmetrical but not 2 to 1, and they are the same length.

Cells are cylindrical, 204S36P. Divided into 12S modules with embedded BMS in each module and Cold plates between each module.
 

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Here's some pictures attached!
 

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The three blue boxes are actually the three PM250DZ inverters. The battery boxes are in fact non symmetrical but not 2 to 1, and they are the same length.
So the inverters are the aluminum housings under the battery packs. This is the first time I've seen that arrangement. Now that I know what to look for, the break between the two inverters on the right side is obvious in the photos, and the length of the inverter matches the blue boxes in the drawing; in Travis's photos, the connectors on the inverters are shown so it is more obvious.

I was wondering if those might be cooling plates; that wouldn't have accounted for the inverters, but with an incomplete car and no detail of the interior of the battery cases, it's all guessing.

With the inverters accounting for the blue boxes, the two-part battery pack configuration is obvious. The removable upper rear vehicle structure is certainly nice for installation. :) In other D2 images, this structure is not removable.

Cells are cylindrical, 204S36P. Divided into 12S modules with embedded BMS in each module and Cold plates between each module.
17 modules, an odd number and so presumably accounting for the slight difference in left and right packs.
About 3 Ah per cell.
With cold plates between modules, this presumably means cooling the cells from their ends, like Rivian.
 
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