Accordion‐Like Fluorinated Graphite Nanosheets with High Power and Energy Densities for Wide‐Temperature, Long Shelf‐Life Sodium/Potassium Primary Batteries
Zhenya Luo, Duanwei Chen, Xiao Wang, Jianyu Huang, Yong Pan, Weixin Lei, Junan Pan
Abstract
Abstract Sodium and potassium are considered to be the most promising anode candidates due to their easy availability, low‐cost and similar chemical properties to lithium. Here, novel 3D accordion‐like fluorinated graphite nanosheets (FGNSs) are reported as cathodes for sodium primary batteries (SPBs) and potassium primary batteries (PPBs). The FGNSs‐x cathode exhibits unprecedented power and energy density due to the impressive 3D structure, high F/C ratio (1.0), and more surface CC bonds (7.14%). The FGNSs‐1.0 exhibits very high specific capacities of 831.3 and 834.1 mAh g −1 for SPBs and PPBs, respectively, close to the theoretical capacity. Besides, the maximum energy density of FGNSs‐1.0 in SPBs and PPBs are 1960.5 and 2144.6 Wh kg −1 , respectively. The maximum power density for Na/CFx and K/CFx batteries could reach up to 7076.8 and 6227.4 W kg −1 , respectively. The electrochemical performance of FGNSs‐1.0 at extreme temperatures (−30 to 100 °C), long storage time (60 days), high mass loading (3.6 mg cm −2 ), and pouch‐type cell is also evaluated for the first time. Surprisingly, FGNSs‐1.0 has outstanding performance in these projects. Therefore, the new‐type Na/CF x and K/CF x primary battery systems developed here have broad application prospects in high‐energy applications that require high‐power, low‐cost, and normal use under extreme conditions.