Efficient potential-tuning strategy through p-type doping for designing cathodes with ultrahigh energy density

Zhiqiang Wang; Da Wang; Zheyi Zou; Tao Song; Dixing Ni; Zhenzhu Li; Xuecheng Shao; Wanjian Yin; Yanchao Wang; Wenwei Luo; Musheng Wu; Maxim Avdeev; Bo Xu; Siqi Shi; Chuying Ouyang; Liquan Chen

doi:10.1093/nsr/nwaa174

Efficient potential-tuning strategy through p-type doping for designing cathodes with ultrahigh energy density

Natl Sci Rev. 2020 Jul 27;7(11):1768-1775. doi: 10.1093/nsr/nwaa174. eCollection 2020 Nov.

Authors

Zhiqiang Wang¹, Da Wang², Zheyi Zou², Tao Song², Dixing Ni¹, Zhenzhu Li³, Xuecheng Shao⁴, Wanjian Yin³, Yanchao Wang⁴, Wenwei Luo¹, Musheng Wu¹, Maxim Avdeev⁵, Bo Xu¹, Siqi Shi², Chuying Ouyang¹, Liquan Chen⁶

Affiliations

¹ Department of Physics, Laboratory for Computational Materials Physics, Jiangxi Normal University, Nanchang 330022, China.
² State Key Laboratory of Advanced Special Steel, School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China.
³ Soochow Institute for Energy and Materials Innovations (SIEMIS), College of Physics, Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China.
⁴ State Key Lab of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China.
⁵ Australian Nuclear Science and Technology Organisation, Kirrawee DC, NSW 2232, Australia.
⁶ Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.

Abstract

Designing new cathodes with high capacity and moderate potential is the key to breaking the energy density ceiling imposed by current intercalation chemistry on rechargeable batteries. The carbonaceous materials provide high capacities but their low potentials limit their application to anodes. Here, we show that Fermi level tuning by p-type doping can be an effective way of dramatically raising electrode potential. We demonstrate that Li(Na)BCF₂/Li(Na)B₂C₂F₂ exhibit such change in Fermi level, enabling them to accommodate Li⁺(Na⁺) with capacities of 290-400 (250-320) mAh g^-1 at potentials of 3.4-3.7 (2.7-2.9) V, delivering ultrahigh energy densities of 1000-1500 Wh kg^-1. This work presents a new strategy in tuning electrode potential through electronic band structure engineering.

Keywords: Li(Na)BCF2/B2C2F2 cathodes; electrochemical potential tuning; p-type doping strategy; ultrahigh energy densities.