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Can you get a picture of the negative terminal of an individual cell?
The Rav4EV uses the 2900 mAh NCR18650PD with a C shaped vent designed to break the bond wire on the terminal when it opens. The C shaped vent is pictured in the Tesla patent but more recent patents also describe a circle shaped vent.
Pansonic recently released the NCR18650BE cell which is also an NCA cell rated at 2C max just like the PD cell, but rated at 3300 mAh! This cell has the same triangular postive terminal as the PD cell but has a circular vent. No other Panasonic cells besides the PD and BE have negative terminal vents! The nominal voltage of a NCA cell is 3.65V so a 3.3 Ah cell would result in a 85.5 kWh pack
The 3400 mAh NCR18650B is a high energy cell not suitable for EV use. The latest high energy cell is the NCR18650G rated at 3600 mAh. Neither of these cells has the Tesla vent on the neg terminal.
Tesla does not use the BMS to balance the pack. They use active impedance control to shuttle charge between bricks. It is always working and it much safer than a typical BMS (battery murder system)
The NCR1850B can deliver 2C. I found not mutch for the NCR18650BE but it looks like its also rated for 2C or less. The 18650PD can deliver 10A which is more then 3C. And the 18650G is not yet on the market maybe for OEMs. http://www.dampfakkus.de/akku_liste-nach-marke.php?marke=Panasonic