Enhanced Ion Conductivity in Conducting Polymer Binder for High‐Performance Silicon Anodes in Advanced Lithium‐Ion Batteries

Abstract

Polymer binders with high ion and electron conductivities are prepared by assembling ionic polymers (polyethylene oxide and polyethylenimine) onto the electrically conducting polymer poly(3,4‐ethylenedioxythiophene): poly(styrenesulfonate) chains. Crosslinking, chemical reductions, and electrostatics increase the modulus of the binders and maintain the integrity of the anode. The polymer binder shows lithium‐ion diffusivity and electron conductivity that are 14 and 90 times higher than those of the widely used carboxymethyl cellulose (with acetylene black) binder, respectively. The silicon anode with the polymer binder has a high reversible capacity of over 2000 mA h g−1 after 500 cycles at a current density of 1.0 A g−1 and maintains a superior capacity of 1500 mA h g−1 at a high current density of 8.0 A g−1.

The Three‐Dimensional Dendrite‐Free Zinc Anode on a Copper Mesh with a Zinc‐Oriented Polyacrylamide Electrolyte Additive

“…[13] Thei ncreased nucleation sites can be achieved owing to the uniform electric field and charge distribution through the surface modification of PA M. Therefore,z inc tends to grow uniformly and eventually forms as mooth plating surface.F rom the Raman spectra (Figure 1b), the characteristic peaks of pristine PA Misobserved at 839 cm À1 (CÀCs ide-chain vibration), 1106 cm À1 (CÀC skeletal stretching), 1319 cm À1 (C À Hbending), 1441 cm À1 (C À Ns tretching), 1610 cm À1 (N À Hb ending), 1665 cm À1 (C = O stretching), and 2925 cm À1 (C À Hs tretching), respectively, indicating that PA Mi salong-chain polymer with abundant acyl groups. [15] Thee lectrolytes with different concentrations of PA M were investigated to optimize the amount of PA M. [16] In the comparison of the electrochemical windows (Figure 1f), the zinc plating potential is decreased from À0.103 to À0.041 Vw ith the added amount of PA Mincreasing,which can be attributed to the activation of PA Mi nt he zinc plating process.T he oxygen evolution potential increases about 0.1 Vafter the addition of PA M. This widened electrochemical window is beneficial to expanding the available voltage range of the batteries.T he chemical stability of zinc was examined by immersing zinc foil in the electrolytes for 7days.The surface morphologies of the soaked zinc foils in the electrolytes with different PA Mc oncentrations are shown in Figure 1g-j. Thei ntensity changes of these peaks are clearly shown in the Supporting Information, Table S1, from which we can conclude that PA M is lied on the metal substrate by the absorption of acyl groups at side chains.O wing to the surface-enhanced Raman scattering,t he group absorbed on the metal surface generally exhibits the relatively strong intensity of Raman signal.…”

3D Network Binder via In Situ Cross‐Linking on Silicon Anodes with Improved Stability for Lithium‐Ion Batteries

“…These polymer binders show promoted binding capacity with Si materials because there can be hydrogen bonding interaction even covalent bonding interaction between the polar groups of the polymer binders and the surface layer of Si materials. Different kinds of conductive binders were also investigated for Si anodes …”

Trifunctional Electrode Additive for High Active Material Content and Volumetric Lithium‐Ion Electrode Densities

“…[1,2] Be it consumer electronics or electric vehicles, the size of the battery and the corresponding amount of deliverable energy and power strongly influences their commercial competitiveness. While there has been some works on dual-function conductive binder, [16][17][18][19][20][21][22][23] these binders have not been accepted into the industry likely due to complicated, toxic, and expensive synthesis methods that are required. As such, the electrode density and volumetric energy density of typical commercial LFP electrodes are only ≈2.0 g cm −3 and ≈1100 Wh L −1 , respectively, indicating much room for improvement.…”