21700 battery cell comparison

The 21700 cell has been mass-produced lately by many companies who were producing 18650, and some of these companies have completely moved to 21700 production. 21700 cells have better energy density (gravimetric and volumetric), higher cycle life, and lower cost per kWh than 18650 cells. 21700 cells make the battery pack more reliable due to the lower number of cells in parallel and reduce costs at the battery pack level. [pdf]