Title: Ionic/electronic conductivity regulation of n-type polyoxadiazole lithium sulfonate conductive polymer binders for high-performance silicon microparticle anodes

Abstract

Low-cost silicon microparticles (SiMP), as a substitute for nanostructured silicon, easily suffer from cracks and fractured during the electrochemical cycle. A novel n-type conductive polymer binder with excellent electronic and ionic conductivities as well as good adhesion, has been successfully designed and applied for high-performance SiMP anodes in lithium-ion batteries to address this problem. Its unique features are attributed to the strong electron-withdrawing oxadiazole ring structure with sulfonate polar groups. The combination of rigid and flexible components in the polymer ensures its good mechanical strength and ductility, which is beneficial to suppress the expansion and contraction of SiMP s during the charge/discharge process. By fine-tuning the monomer ratio, the conjugation and sulfonation degrees of the polymer can be precisely controlled to regulate its ionic and electronic conductivities, which has been systematically analyzed with the help of an electrochemical test method, filling in the gap on the conductivity measurement of the polymer in the doping state. The experimental results indicate that the cell with the developed n-type polymer binder and SiMP (~0.5 μm) anodes achieves much better cycling performance than traditional non-conductive binders. It has been considered that the initial capacity of the SiMP anode is controlled by the synergetic effectmore » of ionic and electronic conductivity of the binder, and the capacity retention mainly depends on its electronic conductivity when the ionic conductivity is sufficient. Here, it is worth noting that the fundamental research of this work is also applicable to other battery systems using conductive polymers in order to achieve high energy density, broadening their practical applications.« less

Authors:

Yu, Yuanyuan  ^[1];

• Search DOE PAGES for author "Yu, Yuanyuan"
• Search DOE PAGES for ORCID "0000-0001-5333-1151"

Gao, Huihui ^[1]; Zhu, Jiadeng ^[2]; Li, Dazhe ^[1]; Wang, Fengxia ^[1]; Jiang, Chunhui ^[1]; Zhong, Tianhaoyue ^[1]; Liang, Shuheng ^[1]; Jiang, Mengjin  ^[1]

• Search DOE PAGES for author "Jiang, Mengjin"
• Search DOE PAGES for ORCID "0000-0001-7403-712X"

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+ Show Author Affiliations

1. Sichuan Univ., Chengdu (China)
2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Publication Date:

Mon Oct 12 00:00:00 EDT 2020

Research Org.:

Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1855688

Grant/Contract Number:  

AC05-00OR22725

Resource Type:

Accepted Manuscript

Journal Name:

Chinese Chemical Letters

Additional Journal Information:

Journal Volume: 32; Journal Issue: 1; Journal ID: ISSN 1001-8417

Publisher:

Elsevier

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; n-Doping; Conductive binder; Electronic conductivity; Ionic conductivity; High-performance silicon microparticle anodes