Constructing a highly efficient aligned conductive network to facilitate depolarized high-areal-capacity electrodes in Li-ion batteries

In order to prepare electrodes with high mass loading and areal capacities, the key issue is to achieve depolarization for both ion and electron transfer on the electrode material surface. In this work, through copolymerization of xanthan gum (XG) and amorphophallus konjac gum (KG) followed by an ice-templating method, aligned electrodes with high areal mass loading of active materials are prepared. In addition to firmly holding active materials together, the prepared KG–XG copolymer also facilitates improved effective porosity as well as homogeneous dispersion of conductive agents (i.e., CNTs). Consequently, with minimum inactive components (i.e., binder and conductive agents), the proposed electrode structure delivers good cycling stability and rate capability under high areal loading (as high as 200 mg cm${}^{-2}$). The excellent electrochemical performance can be attributed to the unique aligned structure where the robust conductive network provides an efficient electron and lithium-ion pathway, and the homogenous porosity is beneficial for the electrolyte percolation, hence the reduced polarization during charge transfer. In addition, this electrode preparation method is found to be universal as it is suitable for various types of anode and cathode materials. (© 2021 Wiley-VCH GmbH)