Sodium‐rich NASICON‐structured cathodes for boosting the energy density and lifespan of sodium‐free‐anode sodium metal batteries
Junxiong Wu,
Cong Lin,
Qinghua Liang,
Guodong Zhou,
Jiapeng Liu,
Gemeng Liang,
Man Wang,
Baohua Li,
Liang Hu,
Francesco Ciucci,
Qiang Liu,
Guohua Chen,
Xiaoliang Yu
Affiliations
Junxiong Wu
Department of Mechanical Engineering Research Institute for Smart Energy, The Hong Kong Polytechnic University Hong Kong China
Cong Lin
Department of Mechanical Engineering Research Institute for Smart Energy, The Hong Kong Polytechnic University Hong Kong China
Qinghua Liang
Department of Chemical Engineering The University of Melbourne Parkville Victoria Australia
Guodong Zhou
Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Hong Kong China
Jiapeng Liu
Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Hong Kong China
Gemeng Liang
Institute for Superconducting & Electronic Materials University of Wollongong Wollongong New South Wales Australia
Man Wang
Department of Mechanical Engineering Research Institute for Smart Energy, The Hong Kong Polytechnic University Hong Kong China
Baohua Li
Shenzhen Key Laboratory on Power Battery Safety and Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate School (SIGS) Shenzhen China
Liang Hu
Department of Mechanical Engineering Research Institute for Smart Energy, The Hong Kong Polytechnic University Hong Kong China
Francesco Ciucci
Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Hong Kong China
Qiang Liu
Department of Mechanical Engineering Research Institute for Smart Energy, The Hong Kong Polytechnic University Hong Kong China
Guohua Chen
Department of Mechanical Engineering Research Institute for Smart Energy, The Hong Kong Polytechnic University Hong Kong China
Xiaoliang Yu
Department of Mechanical Engineering Research Institute for Smart Energy, The Hong Kong Polytechnic University Hong Kong China
Abstract Rechargeable sodium metal batteries (SMBs) have emerged as promising alternatives to commercial Li‐ion batteries because of the natural abundance and low cost of sodium resources. However, the overuse of metallic sodium in conventional SMBs limits their energy densities and leads to severe safety concerns. Herein, we propose a sodium‐free‐anode SMB (SFA‐SMB) configuration consisting of a sodium‐rich Na superionic conductor‐structured cathode and a bare Al/C current collector to address the above challenges. Sodiated Na3V2(PO4)3 in the form of Na5V2(PO4)3 was investigated as a cathode to provide a stable and controllable sodium source in the SFA‐SMB. It provides not only remarkable Coulombic efficiencies of Na plating/stripping cycles but also a highly reversible three‐electron redox reaction within 1.0–3.8 V versus Na/Na+ confirmed by structural/electrochemical measurements. Consequently, an ultrahigh energy density of 400 Wh kg−1 was achieved for the SFA‐SMB with fast Na storage kinetics and impressive capacity retention of 93% after 130 cycles. A narrowed voltage window (3.0–3.8 V vs. Na/Na+) further increased the lifespan to over 300 cycles with a high retained specific energy of 320 Wh kg−1. Therefore, the proposed SFA‐SMB configuration opens a new avenue for fabricating next‐generation batteries with high energy densities and long lifetimes.
