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[Electric Terry]

Terry

Thanks for the post of the detailed information and the sizing up of the 2170 in comparison to the density of the Farasis pack. The initial idea of the post was more in the scope of the cost of the Farassis cells being more competitive now that there will be serious competition with the Tesla cells. Regretfully this thread went south when a user got his feeling hurt because he was mis-informed on the Tesla site what a great guy Elon was.

Since you're in tune to the physical size of the cells in a Zero application - just how much space and more importantly how much weight do you feel it would take to do a 2170 installation in a Zero. As we are all aware the cost of a Zero is its own biggest hindrance to most riders. The 2170 would be a game changer in the bikes price. Using your calculations would it be possible to get a 13K  pack in the space of the frame?

If not - even if we dedicated the tank space to cells to reduce the cost of the Zero it would seem to me it would be a major advantage since then the "Electric Bike" could be more competitive on the ICE market. 

I feel strongly that in due time be it Zero, a rider or another manufacture, we will indeed see 2170 powered bikes. As you are aware while the cylinder shape of the cells takes more space, however the design in nature would lend to simple air cooling / heating of the cells which would be a major advantage to our application.

Regards

Hey Mike,

First I don't think the batteries themselves cost $1000/kWh.  You're getting that from the cost of a powertank which has its own BMS ($500-$800 or more itself), contactor, fuse, Anderson connector, and then is the price of the battery to the user, not what Zero pays for it.

My guess is it's less than half that but lets say $500/kWh to Zero.  The difference isn't enough to try to design something new, when you would need 3 times as many cells to get the same power.

I can appreciate what you are thinking about, but the danger of a user trying to tab weld his own pack (Tesla uses an automated machine that is perfect at this) could be very dangerous and I just don't think worth the risk by any means.

However I say that and if you wanted to "add" range.  You could build your own pack of 2170's that adds up to 116 volts, and have your own switch that you can connect once the bike is on that connects to your controller.

Caution, there are many dangers in doing this!!   In fact this is so dangerous that I am not recommending anyone ever try this.  You can destroy your Zero and cause your auxiliary pack to catch fire if you make a mistake or crash your bike.  But since I've said that, here you go...

One you need to make sure the packs are within 1-2 volts when connecting.   You can not leave it connected because the Sevcon will not turn on if it senses voltage, it will think the last time it turned on the contactor welded shut from arcing. 

Two, your discharge curve will be slightly different, as long as you ride real slow and charge slow this shouldn't be a problem.  However if you ride fast, you could end up pulling all power from the 2170 cells which are not designed themselves to put out a lot of power (3C discharge limit) unless you parallel like 30 or more of them together like Tesla does to get short bursts of acceleration with preheating them to 50C, and then cooling them immediately after.  A complicated process that you won't be able to do on a Zero.  Designing a liquid heating and cooling system for a bike doesn't make sense.

You also need to fuse your pack as close to the battery terminals as possible, although I just realized since you can't heat or cool these cells it's a no go.  These cells have a very high internal resistance compared to Zero's Farasis cells.  They are going to get very hot and you will need thermistors placed all over the pack with a warning light to pull over and wait for a few hours to let them cool.  This just isn't going to work.  These cells were originally designed to be in a application with very little power usage (high max energy/low power) i.e. max laptop runtime, but only using like 30 watts. 

Tesla might have them "burst" power for 2.4 seconds, and many cells can do that for a very very short time and be ok, but they were designed to have like a 1/3C discharge.  Tesla has like a 250 mile range, and this is at least 3 hours of driving.  The cells were originally designed for laptops which might be also on for 3 or more hours.  It will be hard to ride your Zero in a way that you only discharge the pack over 3 hours time.  You would need to ride at about 40 mph or slower.

Again I appreciate your persistence but this just isn't going to work right now.


Here's where I see it possibly working one day.  If Zero ever built a touring bike, and had twice the battery volume, you could possibly use batteries designed for laptops, as you would have enough to meet the power requirements of going down the highway, and short bursts of acceleration.  Would probably not be offered in the SR or DSR package, just as an S. 

You would have twice the range for perhaps the same cost in batteries, but performance is limited and where do you put twice as many batteries of the current volume?  Then comes the issue with charging.  If you are building a touring bike, you want to charge fast!  Trust me I know this.  You ideally want 15 minute charge stops.   Tesla has a handicap, it's the cells it uses.  It's charging as fast as it can with max cooling once the cell gets to 50C.  And it takes over an hour for a full charge, but 80% in 40 minutes.  Other manufacturers are already doing 80% in 20 minutes, because their cells have lower internal resistance AND cooling. 

My guess is Tesla realized this a long time ago, and part of the reason to build the Gigafactory was to make it's own custom cells.  I'd be willing to bet the 2170 cells will have lower energy density and higher power density than the current 18650's do.  As we go forward with EV's the answer is power density, where in the early days it was energy density.  Everyone was fighting for the vehicles just to have a useful daily range, but now that we have that, to also make it good for long distance trips, extremely fast charging is needed, and so the cells need to be more power dense than energy dense.  As long as Teslas can get from supercharger to supercharger, it's best to let them charge faster once they get there.

Technically Zero could be able to charge faster than any of the car manufacturers if you could start charging with the pack very warm, and then hold it there.  But you would need cooling, and that's not going to happen on a motorcycle very easily. 

Terry

[Erasmo]

I still don't think that the Tesla Gigafactory cells are going to be offered to any company not associated with the factory any time soon.  The companies that have an interest in the factory need the cells for their own products and are not going to want to hand them out to the public until all of their battery needs are satisfied - and that could take a while.   

Tesla will indeed use the batteries in their own products, that's the whole reason they build the factory in the first place. On the other hand it will free up capacity in the other factories, Tesla bought a lot of batteries from them, like a lot a lot.

[Low On Cash]

Thanks to all for the reply’s - My $1000 kw estimate was for “ready to use power”. I was using a retail figure of the tank battery and not meant to represent the wholesale or retail of the Zero’s pack itself.

My original post was more inline of a lower price of the Zero pack to hopefully make electric bikes more affordable and competitive.  Keep in mind, cells become 5-6% more efficient each year, this means that in a few years, our Zero pack size will reduce considerable in size.

I feel a fair retail estimate for the Zero pack is around $700 kw or around $9,000 retail. In retrospect, a 13kw / 2170 pack at $4000, would be half of the cost of the current Farisis pouch pack. In long term, If Zero or in fact any manufacture could offer an electric bike for $5000 less than current prices, it would be a major step forward in making them affordable.

As we look at the cost of the Zero motorcycle less electronics, we have to realize the actual bikes value is around $5,000, the rest is electronics. If manufactures can build and sell a motorcycle with an engine and transmission for $7000 and make money, then we know the Zero chassis must be $4-5k. Using these figures, the end user is paying a retail amount of around  $10,000 for the pack since a DSR/SR is around $18,000 delivered.

Since I have been building battery packs way before 1992 when I designed the first electric radio control helicopter, I could easily buy a Tesla Wall 2 and build a 2170 Zero pack, however I have no desire to build batteries, I’m perfectly happy with the power and range of my “Stock” 2017 DSR.

The 2170 cells could easily be factory or sub factory welded in any arrangement to fit the Zero’s present or modified battery case or arranged to conform to any manufactures specs. I have worked with companies in the RC industry who perform this service for numerous RC manufactures.

Again, I feel the cylinder shape of the 2170 cells would be an advantage over pouch cells since it provides a void between the cells for uniform air cooling or heating, which is an important factor in different climates. Another advantage would be for “Race” applications where cooling is needed for aggressive use and fast charging, something the pouch cells can not provide.
Keep in mind, unlike a larger pouch cell, due to the relative small amperage of each 2170 individual cell, very little heat is generated in the cell itself. This combined by the fact there is air volume around each cell allows them to cool more efficiently then pouch cells.

The 2170 cell is roughly 10% larger than the 18650, and has 30% more capacity so its power density is pretty amazing. It is my understanding that Panasonic designed the 2170 chemistry and the first cells were produced in Japan by Panosonic.
As we all know, Tesla will be the world manufacture, what a switch - now we’ll be shipping cells to china and Japan instead of the opposite, Trump will like that! The Panasonic Corporation will also be the conduit to third party vendors. The short term for Tesla and the 2170 cell is production for the Tesla Wall 2 to recover cost - then of course the 2170 will be the bread and butter to power all future Tesla models to include the Tesla 3 & X.


The motivation and timing for Tesla’s development of the 2170 cell was to make Model 3 a reality.  Essentially, when Elon announced the Model 3, it was impossible to build the car with the quoted range at the published price. Using the18650 cells from Panasonic for the Model 3 was not even an option for cost/performance reasons. If not for the 2170’s existence, the Model 3 project would have less range, more cost, or be scraped!  The primary reason for the Model 3’s delay is simple, it was waiting for the 2170 cell to happen.
 
Regarding cost - Tesla announced once production is up to speed, their cost on the 2170 may be as low as $100 kw. At present, the larger Power Wall systems are at a cost of only $250 kw.  Even though the chemistry is out of the bag for other companies to benefit, few if any manufactures will be able to compete with Tesla since no one, not even China or Japan can compete with the Giga factory.

Regards - Mike

[Justin Andrews]

Other manufacturers are already doing 80% in 20 minutes, because their cells have lower internal resistance AND cooling. 

For example the Energica Ego is supposed to be able to charge this quickly, and I suspect even that will be obsolete tech in a couple of years time. So your right Tesla needs to play catch up.

[Low On Cash]

By the way Electric Terry - I wanted to mention you are my Electric Bike Hero and the reason I bought my 2017 DSR!

Thanks for all your efforts!

[Killroy]

By the way Electric Terry - I wanted to mention you are my Electric Bike Hero and the reason I bought my 2017 DSR!

Thanks for all your efforts!

Mike, after all that heated discussion, its nice to hear your positive message.