High‐Performance Li–Se Battery Enabled via a One‐Piece Cathode Design

• Published in: Advanced energy materials 2020-02, Vol.10 (5), p.n/a
• Main Authors: Kim, Soochan, Cho, Misuk, Lee, Youngkwan
• Format: Article
• Language: English
• Subjects: Cathodes; Chemical reactions; Cycle ratio; Decay rate; electrodeposition; Electrodes; Energy storage; highly stable cycling; Li–Se batteries; one‐piece electrodes; Polymers; Separators; solid polymer electrolytes
• ISSN: 1614-6832; 1614-6840
• DOI: 10.1002/aenm.201903477

A high‐performance Li–Se battery is demonstrated by adopting a novel Se cathode design. The Se cathode is a one‐piece body combined with a Se deposited current collector and a solid polymer electrolyte (SPE). In the preparation of the Se cathode, Se is electrodeposited on Ni‐foam, and the pores are filled with SPE layers. Through this electrodeposition, the cathode is easily fabricated, and charge transports are facile. The use of the SPE layer offers a durable Se electrode, enhancing ion pathways, securing safety, and suppressing undesirable electrochemical reactions. Li–Se batteries assembled with the one‐piece Se cathode and Li‐metal anode, without using conductive carbon, polymer binder, and separator, exhibit ultrastable performance with a low capacity decay of 0.001% per cycle at 1 C over 3000 cycles. The rational design of a one‐piece electrode may hold great promise for the future development of energy storage devices with facile fabrication process and long‐term stability. A one‐piece Se cathode without a carbon, binder or separator is prepared by a simple manufacturing system which involves combined electrodeposition of selenium and incorporation of a solid polymer electrolyte. Moreover, the Li–Se battery with a one‐piece Se cathode presents enhanced safety and ultrastable battery performance with a low capacity decay of 0.001% per cycle at 1 C over 3000 cycles.