High-Energy and Long-Lifespan Potassium–Sulfur Batteries Enabled by Concentrated Electrolyte
Journal article, 2022

Potassium–sulfur (K–S) batteries are emerging as low-cost and high-capacity energy-storage technology. However, conventional K–S batteries suffer from two critical issues that have not yet been successfully resolved: the dissolution of potassium polysulfides (KPS) into the liquid electrolyte and the formation of K dendrites on the K metal anode, which lead to inadequate cycling efficiencies with a low reversible capacity. Herein, a high-capacity and long cycle-life K–S battery consisting of a highly concentrated electrolyte (HCE) (4.34 mol kg−1 potassium bis(fluorosulfonyl)imide in a 1,2-Dimethoxyethane) and a sulfurized polyacrylonitrile (SPAN) cathode is presented The application of a HCE efficiently suppresses the dendritic growth of K, as evidenced by operando optical imaging and phase field modeling, owing to the reduced K-ion depletion on the electrode surface and a uniform Faradaic current density over the K metal anode surface. Additionally, because S is covalently bonded to the C backbone of PAN in the SPAN structure, the SPAN cathode inhibits the dissolution of KPS. These features generate synergy that the proposed K–S battery can provide a practical areal capacity of 2.5 mAh cm−2 and unprecedented lifetimes with high Coulombic efficiencies over 700 cycles.

potassium-sulfur batteries

concentrated electrolytes

high areal capacities

SPAN cathodes

dendrite-free

Author

Suyeong Lee

Chonnam National University

Hyeona Park

Chonnam National University

Josef Rizell

Chalmers, Physics, Materials Physics

Un Hyuck Kim

Hanyang University

Yangyang Liu

Moscow Institute of Physics and Technology

Xieyu Xu

Moscow State University

Shizhao Xiong

Chalmers, Physics, Materials Physics

Aleksandar Matic

Chalmers, Physics, Materials Physics

Adi Tiara Zikri

Chonnam National University

Hyokyeong Kang

Chonnam National University

Yang Kook Sun

Hanyang University

Jaekook Kim

Chonnam National University

Jang Yeon Hwang

Chonnam National University

Advanced Functional Materials

1616-301X (ISSN) 16163028 (eISSN)

Vol. 32 46 2209145

Subject Categories

Inorganic Chemistry

Materials Chemistry

Other Chemical Engineering

DOI

10.1002/adfm.202209145

More information

Latest update

3/7/2024 9