ElectricMotorcycleForum.com
General Category => Electric Motorcycle News => Topic started by: Richard230 on November 26, 2013, 09:24:03 PM
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Here is an article by WebBikeWorld describing the few new and slightly improved motorcycles that were shown at the Tokyo Motor Show this year. Near the bottom of the page are shown the electric motorcycles, scooters and a car (including whatever that Kawasaki thing is) that were at the show. Unfortunately, nothing appears ready to hit the market. Electric vehicles seem to remain mostly an effort to gain attention and maybe to judge the public's reaction to various electric concept vehicle ideas.
http://www.webbikeworld.com/motorcycle-news/2013/2013-tokyo-motor-show.htm (http://www.webbikeworld.com/motorcycle-news/2013/2013-tokyo-motor-show.htm)
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More about Kawasaki's J Concept. I still don't get it. Plus they are apparently using it to showcase their "GIGACELL high-capacity nickel-metal hydride battery technology". What's up with that? I thought that battery technology was out and Lithium was in?
http://blog.motorcycle.com/2013/12/11/videos/watch-kawasaki-j-concept-transform-video/?utm_source=mo12122013&utm_medium=email&utm_campaign=weekly (http://blog.motorcycle.com/2013/12/11/videos/watch-kawasaki-j-concept-transform-video/?utm_source=mo12122013&utm_medium=email&utm_campaign=weekly)
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http://www.khi.co.jp/english/gigacell/intro/spec.html (http://www.khi.co.jp/english/gigacell/intro/spec.html)
Energy density per unit weight 21Wh/kg
The 5.1 kWh module weighs 248 kg (~550 lb).
Power density is a little better - 500W/kg. This is at least close to Zero's packs - a ZF2.8 module can put out around 22 kW for short bursts, or around 1200W/kg.
I don't think Lithium-based batteries have much to worry about for vehicle applications. Kawasaki is aiming their Gigacell NiMH at grid balancing, wind storage, and other applications where gravimetric density is not a concern.
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Given how stable, long lasting and forgiving NiMH is, I'd say that it could be a good choice for those tasks as well.
And it does a good job in the Prius as well, NiMH has shown its worth as a traction pack too.
I think we all accept the future as it appears is lithum, both Lithium-Sulpher, and Lithium-Air will eventually and hopefully arrive and vastly improve the battery packs we use. I truly hope in a few years time I look back at the bikes we ride today, and shake my head wondering at how obsolete and short ranged they were...
Then hop on my new electric bike and do a 400 mile ride on a single charge.
That's MY dream.
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I think for cars we will quickly see high-C rate lithium phased out. 40-50 kWh packs should be relatively inexpensive to produce, that's a 2-3C discharge rate for a conventional sedan and a 1-2C charge rate.
Less expensive EVs - targeting a $20-25k price point - may stay with a 20 kWh pack, and will still need to discharge at 4-5C and charge at 2+C.
In some ways I like to think of the battery as the "engine" and the motor/controller as the "transmission". As with a gas motorcycle, the "engine" weight dominates the vehicle .. so that it's difficult to make a big/powerful engine unless you are willing to tolerate a heavy vehicle.
Current racing bikes do this with a high C-rate battery pack, to get 100-130 kW out of the battery for short periods of time.
Even though this power/bike+rider weight ratio is higher than on a car, there is still room to improve. MotoGP power levels are around 200 kW, that probably represents a cap on how much power is useful. So we will likely continue to need high C-rate packs for racing for the forseeable future, and perhaps for sporting applications too.
However, by the time we have 50-60 kWh packs for your 400 mile ride, Justin, we will probably only need 2-3C of maximum discharge rate even for a sportbike, and a touring bike can get away with 1-2C.
If an assembled battery reaches the target price of $125/kWh, then a 20 kWh pack will cost $2500 and a 40 kWh pack will cost $5000. Price will obviously be somewhat higher than cost, but when costs reach this level then the primary design decision for pack size will be bike mass/size and target charge/discharge rates.
My dream bike: Tesla builds an aerodynamic 40 kWh touring bike with Supercharger inlet. ~300 miles of highway range, 50% charge = 150 highway miles in 20 minutes on Supercharger.
They could build this with technology available today. It would be big, heavy, and expensive even in volume - probably 800 pounds and $30000 to $35000. More realistically, $45k in low volume production.
I don't think they will.. it's not in their core business line. Maybe they could license their battery packs and Supercharger inlet to a third party. (Brutus?)
Without the high-power DC charging stations - and CHAdeMO and J1772 DC look to be locked into a depressing scorched-earth war - then touring bikes are not really practical. So maybe it will be 3-5 years until the fast DC standards settle, and battery prices come down, before we see a true touring bike.
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To be fair, with decent charging times, which are already almost reachable with DC charging. A 200 mile at 60-70 mph range bike would probably make a decent touring bike as well. Stopping for a bite to eat after 150 or so miles is pretty normal, and in that time you'd be able to top off the battery for the next leg of the ride.
This is why I think next years Zeros with power tank and DC charging options might "almost" make a useful long range bike.
I'm hanging on for a year or two, as I reckon the touring electric is almost with us.
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As far as MotoGP power levels being at the limits, I actually suspect that the tractability and super fine traction control afforded an electric drivetrain may actually allow for a big hike in what people think is possible for top power limits on a racing motorcycle. But this relates to sportbikes, and a market I think Brammo is interested in. In order to make an impression on people Brammo needs to take the Literbikes head on in power and range. Mission Motorcycles looks like it will do just that this year, and I believe an street going Empulse RR could do just that as well. EBoz already beat his lap time on the stock Japanese liters bikes at Miller on last year's RR. The issue is charge time and price. $15,000 with a 3C charge rate is a tall order. And range would still be an issue when highway cruising. But these bikes would require 150kW+ motors and hence a fairly high discharge rate from the cells as well.
I wonder if not all of the current available CHAdeMO chargers being able to do bikes with 100V systems give J1772DC an edge if they don't make the same mistake. Or everyone will just lease Tesla's tech, should they make it available.
For the record I'd much rather Brammo or Zero made a touring bike than Tesla. But that's me.
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Bikes will be an insignificant percentage of users charging from DC. Those charging systems are going to be designed with their primary use case, which is charging high voltage car battery packs. So bikes will have to adopt a similar pack configuration. Zero and Brammo are still relatively low voltage. Mission, Lightning, BRD, KTM, and likely other manufacturers are building higher voltage systems that would be better suited for DC charging.
The J1772 DC and CHAdeMO fight is going to delay standards adoption, unfortunately. But perhaps the resolution of that war will coincide with high-voltage production bikes.
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If an assembled battery reaches the target price of $125/kWh, then a 20 kWh pack will cost $2500 and a 40 kWh pack will cost $5000. Price will obviously be somewhat higher than cost, but when costs reach this level then the primary design decision for pack size will be bike mass/size and target charge/discharge rates.
Ive seen suggestion that Tesla are paying $170 per Kwh for their custom Panasonic 18650 cells, and the Chinese cells have already dropped to $75 per Kwh for 4100mAh 18650's. If you trust them! Tesla seem to have come up with a bit of a master stroke by building their packs from 18650. Hopefully its something Zero/Brammo are looking into.
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Most of the capacity tests I've seen on high-Ah chinese knockoff cells show them at half label capacity or less. I wouldn't put any faith in a white label 18650 claiming that much capacity.
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Ive seen suggestion that Tesla are paying $170 per Kwh for their custom Panasonic 18650 cells, and the Chinese cells have already dropped to $75 per Kwh for 4100mAh 18650's. If you trust them! Tesla seem to have come up with a bit of a master stroke by building their packs from 18650. Hopefully its something Zero/Brammo are looking into.
I think you'll find early Brammo packs used that or a similar form to the 18650s. They moved to prismatics, and I don't think they did so lightly.
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The Valence modules in the Enertia Classic did indeed use cylindrical cells (I think 3.2V 1.4Ah 18650?), inside of Valence-assembled modules. The density wasn't great, but their longevity seems to be pretty good. Compare the durability of the Enertia Classics to the 2009-2010 era Zero bikes with Molicel cells.
Another way of looking at it though: Brammo designed the Enertia with 6 components to the battery, going down to the module at the lowest level. They probably could have designed better modules, but I guess they viewed other engineering tasks as being more important.
Brammo designed the Empulse with 7 modules, each module consisting of 36 cells for a total of 252 cells. This is a fair leap up in complexity for them, particularly for battery modules assembled in the US (labor = $$).
Going to a 18650 type assembly is another leap in complexity of this order, as a similar size 18650 pack will involve one or two thousand cells.
There are other reasons to prefer pouch cells over cylindrical cells - typically better power - but I don't doubt Brammo is keeping "tabs" on advances in cylindrical cells and price drops.
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I still don't get it. Plus they are apparently using it to showcase their "GIGACELL high-capacity nickel-metal hydride battery technology". What's up with that? I thought that battery technology was out and Lithium was in?
Nickel is heavy! I swapped out my 3 kWh NiMH battery pack in my Vectrix for a 6 kWh Li-ion pack and reduced the weight of the bike by 5 lbs.
It does seem strange that Kawasaki would use NiMH.