2170 cell format: why and who makes?

[Brando]

All Things You Need to Know about 21700 Battery
All Things You Need to Know about Tesla 21700 / 20700 Battery

also mentions other formats such as 26650 and controlling heat 2170 seems the sweet spot for current chemistries
The New 21700 format Lithium Cells in 2017

As of 2017 Samsung and Panasonic seem to be the largest suppliers
note: So far Tesla/Panasonic partnership only seems to supply Tesla products.
2nd note: LG Chem did supply 18650, I think, for original Roadster upgrade pack.

 

[Brando]

Elon Musk: 21700 Will Be the Future

The Future will be 21700？ - DNK, Lithium ion Battery Pack Manufacturer and Supplier

 

[acoste]

The energy density of the 18650 and the 2170 cells is nearly the same. Total capacity / total battery weight is better.

 

[renim]

18650 is standard, protected 18650 is also known as 19670

20700 - 21700 - 20720 these are basically the same cells, perhaps differing protection.

22650, 20650, 32650 these are fat variants of 18650


20700 - 21700 - 20720 were developed to upsize for ebikes, power tools etc. packaging wise, its pretty compelling to go from a 2P to a 1P, or a 3P to a 2P configuration. Tesla just picked one from their favoured supplier, and benchmarked with Panasonic's competitors.

22650 etc, represents a tighter focus on cell cost, so Chinese suppliers and readily switch between 18650 to 22650 close to seamlessly. Its really represents a very cost focused way to have chinese LiFePO4. Different intent, generally different market.

 

[Brando]

18650 is standard, protected 18650 is also known as 19670

20700 - 21700 - 20720 these are basically the same cells, perhaps differing protection.

22650, 20650, 32650 these are fat variants of 18650


20700 - 21700 - 20720 were developed to upsize for ebikes, power tools etc. packaging wise, its pretty compelling to go from a 2P to a 1P, or a 3P to a 2P configuration. Tesla just picked one from their favoured supplier, and benchmarked with Panasonic's competitors.

22650 etc, represents a tighter focus on cell cost, so Chinese suppliers and readily switch between 18650 to 22650 close to seamlessly. Its really represents a very cost focused way to have chinese LiFePO4. Different intent, generally different market.

you are confusing/mixing the format with the chemistry. You can put any chemistry into most any package [format].
Those numbers represent the format size [size of the battery package]. width/length
21700 = 21mm by 700mm just the format, the package
Chemistries used?

The article above articles will explain why optimizing on the 2170 format with CURRENT chemistries.

 

[Brando]

you are confusing/mixing the format with the chemistry. You can put any chemistry into most any package [format].
Those numbers represent the format size [size of the battery package]. width/length
21700 = 21mm by 700mm just the format, the package
Chemistries used?

The article above articles will explain why optimizing on the 2170 format with CURRENT chemistries.

ERROR: just noticed 21mm x 70mm not 700