Binary Network of Conductive Elastic Polymer Constraining Nanosilicon for a High-Performance Lithium-Ion Battery

Abstract

Silicon-based anodes are attracting more interest in both science and industry due to their high energy density. However, the traditional polymeric binder and carbon additive mixture cannot successfully accommodate the huge volume change and maintain good conductivity when cycling. Herein, we report a multifunctional polymeric binder (PPTU) synthesized by the cross-linking of conducting polymer (PEDOT:PSS) and stretchable polymer poly­(ether-thioureas) (PETU). The multifunctional polymeric binder could be curved on the surfaces of nanosilicon particles, forming an interweaving continuous three-dimensional network, which is beneficial to electron transfer and the mechanical stability. Furthermore, the binder is elastic and adhesive, and which can accommodate the huge volume change of silicon to keep its integrity. Utilizing this multifunctional polymeric binder instead of commercial poly­(acrylic acid) binder and carbon black mixtures, the nanosilicon anode demonstrates enhanced cycling stability (2081 mAhg–1 after 300 cycles) and rate performance (908 mAhg–1 at 8 Ag–1). The multifunctional polymeric binder has high conductivity, elasticity, and self-healing properties is a promising binder to promote progress toward a high performance lithium-ion battery.

In Situ Construction of a Multifunctional Interface Regulator with Amino-Modified Conjugated Diene toward High-Rate and Long-Cycle Silicon Anodes

“…The FTIR spectra of PA dried at 60, 120, and 150 °C are shown in Figure a. Obviously, all the three samples show two characteristic peaks at 3435.1 and 1633.7 cm –1 , corresponding to the −NH 2 stretching and N–H deformation vibration, respectively . However, compared with the other two samples, the sample dried at 150 °C exhibits two new peaks at 1687.7 and 1384.8 cm –1 , which are the CC bond and C–H vibration, respectively, indicating that the conjugated CC functional bond has been developed, which can be also verified by the migration of the −NH 2 peak to 3402.3 cm –1 .…”

Porous interface for fast charging silicon anode

“…Advanced polymer design would accommodate large anisotropic stresses from the silicon core during fast charging. Recently, conductive elastic polymer constructed by cross‐linking of conducting polymer (PEDOT:PSS) and stretchable polymer poly(ether‐thioureas) were utilized in silicon anodes, performing an excellent rate performance of 908 mAh g −1 at 8 A g −1 31 . Self‐expanding Li + transport channels were designed to construct a fast‐charging anode and realize fast‐charging batteries, reaching 342 mAh g −1 under a 6 C rate 37 …”

Scalable Fabrication of Silicon‐Graphite Microsphere by Mechanical Processing for Lithium‐Ion Battery Anode with Large Capacity and High Cycling Stability

“…[1][2][3] Silicon (Si) is the next-generation anode material, owing to the advantages of high theoretical capacity (4200 mAh g À 1 , ten times higher than that of conventional graphite anodes), abundant reserves on the earth, low cost and reasonable voltage platform (below 0.5 V vs. Li/Li + ). [4,5] However, silicon anode suffers from the huge volume expansion (4 00 %) during lithiation, structural collapse caused by the delithiation and poor electrical conductivity, thus, the poor electrochemical performance of which hinders the commercial application. [6,7] In order to solve the above problems, numerous strategies have been developed.…”

“…As the emerging market of portable electronic devices and electric powered vehicles, even the advent of electric powered aircrafts in the future, there is a fast growing demand for lithium‐ion batteries (LIBs) with high energy density and long cycle stability [1–3] . Silicon (Si) is the next‐generation anode material, owing to the advantages of high theoretical capacity (4200 mAh g −1 , ten times higher than that of conventional graphite anodes), abundant reserves on the earth, low cost and reasonable voltage platform (below 0.5 V vs. Li/Li + ) [4,5] . However, silicon anode suffers from the huge volume expansion (∼400 %) during lithiation, structural collapse caused by the de‐lithiation and poor electrical conductivity, thus, the poor electrochemical performance of which hinders the commercial application [6,7] …”