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[Doug S]

This is good stuff, guys, REALLY good stuff! Even the most reluctant of riders/drivers will have to concede EVs are worth having when they're getting their butts handed to them by EVs.

[NEW2elec]

Doug S, your so right.  That's the "get on board or get left behind" moment. 

ZeroBrian, your right in the fact it's not "currently" a Zero product, watching the history of Carroll Shelby and Ford's complicated relationship, I think maybe Zero needs to see the video most of all.

A side question from an electronic layman if I could.
I saw some use of Skeleton ultra capacitors with batteries to better capture the kinetic energy with regen braking and discharge it for the acceleration after braking and leveling out the high amp demands on the battery cells.  They talked about using them in buses and other large EVs but it seemed like a great thing for road racing as well if the space allows.
I didn't know if anyone had tried this concept out or if it's just a non starter project for some reason.
Thanks.

[ZeroBrian]

Doug S, your so right.  That's the "get on board or get left behind" moment. 

ZeroBrian, your right in the fact it's not "currently" a Zero product, watching the history of Carroll Shelby and Ford's complicated relationship, I think maybe Zero needs to see the video most of all.

A side question from an electronic layman if I could.
I saw some use of Skeleton ultra capacitors with batteries to better capture the kinetic energy with regen braking and discharge it for the acceleration after braking and leveling out the high amp demands on the battery cells.  They talked about using them in buses and other large EVs but it seemed like a great thing for road racing as well if the space allows.
I didn't know if anyone had tried this concept out or if it's just a non starter project for some reason.
Thanks.

Heh... Thanks. I think.

Buffering the primary traction battery with an ulta-capacitor (or even alternate chemsitry) is definitely an interesting concept and I expect we may see more "creative" solutions like this when you need to maximize range and keep the pack cost as low as possible (I.e. large, on-road vehicles).  Especially when you have a very good understanding of the duty cycle of the vehicle so you can optimize the energy recovery opportunity.  Commercial trucks and buses make a lot of sense to me based on this.  Mostly, these concepts run into challenges around the power conversion between the two packs as the current flow between the two needs to be controlled.  For the Lightfighter, we have pretty high peak power and continuous power requirements, and the duty cycle can change pretty dramatically from track to track.  It also kind of works against the philosophy of simplification of the systems to be able to run the bike without an army of Engineers and programmers.  All that said, what remains interesting to me after all of these years (>10 since the 2009 IOM TXGP race!) is that we're still at the tip of the iceberg for the development possibilities.  We just need more people/teams out there continuing to try these ideas and push the technology...       

[Doug S]

There's nothing magic about ultracaps, they're just one more technology that may or may not be useful for EVs.

Their main advantage is that they can charge and discharge extremely fast. So for a quick burst of acceleration, they're hard to beat. I suppose you could also regen much faster than with a battery pack, but I think generally a battery pack is able to handle any regen currents you want on and EV.

Their downsides are fairly important, too, though. First, their energy density (last I looked) was about 1/10th that of a li-ion battery. So they're really not very good for primary energy storage. They are making gains, though, and last time I looked was a while ago, so they may be much closer now.

Second, their charge/discharge curve is perfectly linear. That may sound good, but mostly it isn't. They go from maximum voltage at full charge to 0 volts when discharged. That's not very vehicle friendly -- you have lots of voltage to work with at full charge, but less and less as it discharges. A battery, conversely, is very non-linear...which again, is pretty much a good thing. For instance, the battery in my 2014 Zero SR (and many Zeros) goes from 116VDC at 100% SoC to maybe 92-95VDC at 0% SoC, with a lot of the curve lying between 100VDC and 110VDC. That's a lot easier to design a drivetrain around.

They might make very good supplementary storage, especially for a racing vehicle. They could supply a few seconds of ultra-high current when coming out of corners, which would be excellent. (In racing it's partly about going fast, but it's more about NOT going SLOW, so the harder you can accelerate out of corners, the better off you are.) But as Brian points out, it would add a ton of complexity, a fair amount of weight and a management headache for the electronics. Plus the batteries are getting better and better at supplying high currents for a short burst, so there may not be all that much advantage anyhow.

Ultracaps are fascinating, and wonderful for many uses, but just not really suited all that well for EVs, in my opinion. At least not yet.

[NEW2elec]

ZeroBrian, it was meant to be a complement.  You did fantastic with a small team and budget like Shelby and perhaps the backing and support follows.

Thanks for taking the time to break down some of the challenges with using the ultra caps.  I had been kicking around the idea since seeing Fully Charged's story about Skeleton.

Doug S thanks to you as well.  I was thinking of a "capacitor tank" to help with slowing down into the corners and shooting out of the apex with the quick discharge.  I guess if it were easy it would have been done already.   

[Doug S]

I was thinking of a "capacitor tank" to help with slowing down into the corners and shooting out of the apex with the quick discharge.  I guess if it were easy it would have been done already.   

That's exactly what I meant by "supplementary storage". It's worth exploring. In fact, isn't that exactly what the F1 car guys are doing now? But...yeah. If it was easy to do, everybody would be doing it.

[Biff]

From what I heard, F1 uses a specially developed  lithium cell by A123 that has extremely high charge and discharge rate, and still good energy density. I also heard they are are extremely expensive maybe 30x the price / wh than typical EV cells. I suspect they don't have a great cycle life (they can afford to change batteries fairly regularly).

-ryan

[nicktulloh]

I saw it posted on the FB page and there will be a part 2 so I thought I'd post it here.  So this guy is a Zero engineer but this is his creation of a light powerful electric race bike.  Also it's a 400V system so I "assume" it will level 3 charge.  Maybe some dots will be connected, who knows.  Enjoy.

https://www.youtube.com/watch?v=E0x_LFOuezM&feature=youtu.be

FFS - amature?

[NEW2elec]

Thanks Nick.

You can be my proofreader from now on.  But I have dysgraphia so you will stay busy.

Rally I kant spell shet.   

[Doug S]

*sigh* I remember my grammar nazi days. It was years before I grew up and accepted that some people just can't spell. It doesn't mean their ideas are any less worthwhile.

BUT if I see the word "whoa" spelled "woah" one more time, I think my head's going to explode!

[NEW2elec]

So yeah it looks like it might be a good idea to use ultracapacitors in a motorcycle for racing.  Or at least these guys thought so.

https://electricmotorcycles.news/nawa-racer-is-powered-by-the-world-first-hybrid-battery-system/

Doug S thanks for the backup by the way.

[Frank]

I would like to see some independent testing: saying the lithium is only 30% efficient when regenerating doesn't sound right....

[Doug S]

De nada, NEW2elec. I'm old and just plain tired of trolls.

I saw that release this morning as well, and I'm with you, Frank. Several claims these guys are making seem to cross well over the line into hype-land. That claim is one of the worst. But also, "ultra-fast charging" is a good point for ultracaps, but that only represents 0.1 kWh out of the 9.1 kWh energy storage system! Or, their claim that "...the efficiency improvements made by a hybrid ultracapacitor battery system can reduce the size of the lithium-ion battery by up to half, or extend the range by up to double..." Well, that's just plain ole bullshit, plain and simple.

Let's put their prototype on the same track as the Lightfighter, and then on the street with a Zero and an Energica and see how their claims hold up.

[Richard230]

Like I said in my original post, I believe that bike shown in the linked article is wishful thinking and not based on anything but a computer screen.   

[Frank]

I've always thought the best use of super-caps would be to combine them with an "energy" (versus "power") battery so as to maintain short-term performance while optimizing space and weight used for the pack. 

Assuming that 50% of the .1 kWh (100 watt-hr) is accessible, if my arithmetic is correct, the caps could potentially provide a 10-second burst at 180 kW.  That's pretty substantial.  Can someone please check my numbers?