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QuantumScape presentation

Discussion in 'EV (Electric Vehicle) Discussion' started by bwilson4web, Dec 9, 2020.

  1. bwilson4web

    bwilson4web BMW i3 and Model 3

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    • Ceramic separator eliminates the SEI layer where lithium combines with electrolyte
    • pouch cells, no cylindrical
    • substantial volume change (not quantified in presentation) between charged and discharged - their graphic shows lithium metal deposited on the anode with a thickness that grows during charge and shrinks during discharge. This can lead to significant mechanical stress unless these cells are packaged in a way that won't lead to separator stress.
    Curious, these are technical challenges that will push off adoption. Some problems can be solved with packaging pouch cells into prismatic. However, the volume change appears to be substantial. A clever prismatic housing might solve part of the problem.

    I won't be investing in QuantumScape but it is interesting.

    Bob Wilson
     
    #1 bwilson4web, Dec 9, 2020
  2. GasperG

    GasperG Senior Member

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    Interesting, you probably won't hear about that "feature" in their one and a half hour "detailed" technical presentation (I didn't watch it).

    The other thing about solid-state was cold temp performance, it seems they solved this problem, but again their data is not in the form I would like, are all li-ions that bad as plotted on their graph, it would also be good to see their cell at +30°C, so one could evaluate the relative hit of cold temps:

    [​IMG]
     
    #2 GasperG, Dec 10, 2020
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