PVDF/Palygorskite Nanowire Composite Electrolyte for 4 V Rechargeable Lithium Batteries with High Energy Density

Pengcheng YAO, Bin ZHU, Haowei ZHAI, Xiangbiao LIAO, Yuxiang ZHU, Weiheng XU, Qian CHENG, Charles JAYYOSI, Zheng LI, Jia ZHU, Kristin M. MYERS, Xi CHEN, Yuan YANG*

*Corresponding author for this work

Research output: Journal PublicationsJournal Article (refereed)peer-review

241 Citations (Scopus)

Abstract

Solid electrolytes are crucial for the development of solid state batteries. Among different types of solid electrolytes, poly(ethylene oxide) (PEO)-based polymer electrolytes have attracted extensive attention owing to their excellent flexibility and easiness for processing. However, their relatively low ionic conductivities and electrochemical instability above 4 V limit their applications in batteries with high energy density. Herein, we prepared poly(vinylidene fluoride) (PVDF) polymer electrolytes with an organic plasticizer, which possesses compatibility with 4 V cathode and high ionic conductivity (1.2 × 10-4 S/cm) at room temperature. We also revealed the importance of plasticizer content to the ionic conductivity. To address weak mechanical strength of the PVDF electrolyte with plasticizer, we introduced palygorskite ((Mg,Al)2Si4O10(OH)) nanowires as a new ceramic filler to form composite solid electrolytes (CPE), which greatly enhances both stiffness and toughness of PVDF-based polymer electrolyte. With 5 wt % of palygorskite nanowires, not only does the elastic modulus of PVDF CPE increase from 9.0 to 96 MPa but also its yield stress is enhanced by 200%. Moreover, numerical modeling uncovers that the strong nanowire-polymer interaction and cross-linking network of nanowires are responsible for such significant enhancement in mechanically robustness. The addition of 5% palygorskite nanowires also enhances transference number of Li+ from 0.21 to 0.54 due to interaction between palygorskite and ClO4- ions. We further demonstrate full cells based on Li(Ni1/3Mn1/3Co1/3)O2 (NMC111) cathode, PVDF/palygorskite CPE, and lithium anode, which can be cycled over 200 times at 0.3 C, with 97% capacity retention. Moreover, the PVDF matrix is much less flammable than PEO electrolytes. Our work illustrates that the PVDF/palygorskite CPE is a promising electrolyte for solid state batteries. © 2018 American Chemical Society.
Original languageEnglish
Pages (from-to)6113-6120
Number of pages8
JournalNano Letters
Volume18
Issue number10
Early online date31 Aug 2018
DOIs
Publication statusPublished - 10 Oct 2018
Externally publishedYes

Keywords

  • energy storage
  • nanowire
  • palygorskite
  • PVDF
  • Solid state battery

Fingerprint

Dive into the research topics of 'PVDF/Palygorskite Nanowire Composite Electrolyte for 4 V Rechargeable Lithium Batteries with High Energy Density'. Together they form a unique fingerprint.

Cite this