20700 cylindrical format cells, 4500-mAh

spinningmagnets

spinningmagnets

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Title edited to reflect new info from the tail-end of the thread.

http://www.businesswire.com/news/home/20150826005361/en/Samsung-SDI-Unveils-E-Bike-Battery-Pack-Runs

http://www.samsungsdi.com/lithium-ion-battery/e-bike

The 22700 format (22mm dia / 70mm long / cylindrical) was speculated to be the "new format" cell that Tesla and Panasonic developed for their next-generation...

Whether they both use 22mm dia or 21mm dia, mass production of fewer cell formats has been very good to the ebike community, so...I hope they both actually end up the same format.

https://endless-sphere.com/forums/viewtopic.php?f=14&t=62859
 
good to see some product after all the rumors.
..Samsung SDI has come up with a battery that has upgraded a maximum of 35% of energy volume, now known as the 21700 battery,
Click to expand...
hmm ?.. +35% increase in capacity.?
in volume alone , the 21700 is 46% more volume ?..( a 22700 would be 60% more volume !)
So it should be no problem having a 5+Ahr cell,..even without any advances in cell chemistry.
I would be surprised if there is not a 6.0Ahr cell within 12 months !

but i dont understand the fuss over the 29E ? ...isnt that a "yesterday" cell ?
 
and Flyer bikes are coming with 4ah cell for the 2016 model,which could be also a 21700 cell
http://www.flyer-bikes.com/fit/index.php/en/fit-en.html

There was a presentation of tesla which stated that this new format of cells would give 30% more energy.We have right now 3.5ah batteries 18650,with this new format we are going to see 4,5ah batteries coming out soon in 2016.
 
Why do we need another format??- am I missing something ?
It reminds me of the MTB wheel thing going on at the mo. 26, no wait, 29...actually your all wrong- 27.5- like how can you ride without them?!?
I can understand car manufacturers wanting bigger formats like the 26650, but of what benefit is an in betweener? Makes me think it's to maximise fill in an existing space.
K
 
Larger cells means fewer parts in the battery assembly, which reduces cost and theoretically improves reliability. A larger cell is also hardly to make defect-free and harder to cool in end use. I imagine 22700 is where the compromise has been struck, possibly also influenced by how far existing 18650 tooling and knowledge could be comfortably stretched.
 
It is all about optimization and finding the best ratio between cost, energy, dimension.
 

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because this is the tallest cell that still fits in the Tesla batter pack enclosure and as wide as they can go to keep the same voltage without compromising safety

telsa want backward compatibility so new packs can be added to old models

the Tesla version may have the positive and neg terminals on the same side if the can so they pack can now be base plate cooled

no more serpentine cooling lines between the cells means they can make the cell fatter
 
I admire the backwards compatibility tesla is wanting... In stark contrast to most manufacturers these days. The main reasons must be manufacturing and optimal form for their vehicles- that's cool but it's not an inherently better size for everyone except maybe.... Cost (with the gigafactory)and I can still fit 700mm between my legs :?
What's a serpentine cooling line?
 
flathill said:
because this is the tallest cell that still fits in the Tesla batter pack enclosure and as wide as they can go to keep the same voltage without compromising safety....
no more serpentine cooling lines between the cells means they can make the cell fatter
Click to expand...
Where did the 20700 cell get introduced into the discussion ?
The 22700 size is the one attributed to Tesla .
.? What has the cell/pack width got to do with voltage ?
..eliminating the cooling tubes won't help with the cell spacing along the rows where the cells are already effectively touching.
http://www.teslamotorsclub.com/showthread.php/34934-Pics-Info-Inside-the-battery-pack/page50?p=953532&viewfull=1#post953532
No, they will need to reconfigure the cell layout (pitch spacing etc). completely to fit in the 22700 size.
You might say it would be easier, ( or at least no harder), to fit in 26650......an established cell size ...with more than double the volume of the 18650 !
So... Why did they chose 22700 ?
 
If you are going to make enough of a given cell (billions?) then, you don't need to use an existing format if a possible new design has a clear benefit. 18650's have been the battery of choice for laptop computers, but they are low C-rate, and compete on lowest price. My 5 year old Toshiba uses 1600-mAh cells in a 3S/2P pack. various DIY pack builds around here from laptop cells (DarkAngel?) has verified a builder would need roughly a 20-Ah pack to reliably provide 20A (assuming the common 12S).

The high-current versions of 18650's has been driven by the cordless tool industry, where contractors will pay a premium for high-power in a small package, along with a long run-time and a long life-cycle. IMHO, we owe the current state of E-bike 18650-cell selection to the cordless tool industry.

If an 18650 cell with an adequate C-rate can now be reliably made with 3500-mAh per cell, the new 21700/22700's should be around 5000-mAh per cell? (assuming no further improvements other than larger size).

My 18V Makita cordless drill uses five 18650 cells, and if the next gen uses 21700's, the physical size wouldn't be much larger, but a 5-Ah dril pack is something that I am certain will sell well.

I think Tesla/Musk are hedging their bets with the new format. They will go in the cars, the power-walls, and I believe...also in cordless tools.
 
Samsung SDI Unveils E-Bike Battery Pack That Runs 100km with Single Charge at Eurobike 2015

http://www.businesswire.com/news/home/20150826005361/en/Samsung-SDI-Unveils-E-Bike-Battery
 
Anybody know how SDI Samsung is doing in getting these batterys and packs out the door?

Tesla's 21700 gigafactory is ramping up too.

The Packs look like they allow users to replace individual 21700 cells without soldering. Atleast in the video it suggests it. I'm convinced a battery pack that lets the average joe to replace the cells himself after 1000 battery cycles.
 
ElectricSushiChef said:
Atleast in the video it suggests it. I'm convinced a battery pack that lets the average joe to replace the cells himself after 1000 battery cycles.
Click to expand...

got link? :D
 
Hillhater said:
Its a freeking CGI. ,!
Or do you believe batteries can hover in the air unsupported also ? :roll:
Has anyone even seen, touched , one of these mythical 21700 cells yet ?
Click to expand...

Yes,
here the panasonic 4ah coming this summer
 

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