Patent Application Publication  Feb. 28, 2019 Sheet 12 of 13  US 2019/0067732 Al  FIG. 10  10000  ~  Na/Na2C606-Conventional-Gravimetric  ~  Na/Na2C606-conventional•Vo!umetrk  ...-.•,t,••••••  Na/Na2C606-inventlve-Gravlmetrk  ~  Na/Na2C606-inventlve-Vo!umetrk  100  1000  Gravimetric energy (Wh/Kg) or Volumetric energy (Wh/L)  ..................................................................................................................................................................................................................... 