Engineering of Lignocellulose Pulp Binder for Ah‐Scale Lithium–Sulfur Batteries

Bamboo-derived lignin-containing cellulose nanofibril is developed as a tough binder for lithium–sulfur batteries, constructs a rigid network with abundant oxygen-containing groups to suppress the volume changes and shuttle effect, opens up a Li⁺ transport channel, and endows the pouch cell with an initial discharge capacity of 1.078 Ah.

Abstract

Natural binders play attractive roles in stabilizing lithium–sulfur (Li–S) battery systems due to their polymeric skeleton and abundant functional structures, but the complex extraction and modification hinder the practical use. Here, lignocellulose, the unbleached product of the pulp industry, is directly developed as a robust binder in Li–S batteries. Benefiting from various oxygen-containing functional groups woven strong hydrogen-bonded network framework, robust mechanical stability, lithium polysulfide anchoring capacity, and high-speed Li⁺ transport channel. The Li–S cell battery delivers an initial discharge capacity of 996 mAh·g⁻¹ at a current density of 0.5 C and can stably run 500 cycles. Moreover, an Ah-scale pouch cell is constructed and delivers notable gravimetric and volumetric energy densities of 322 Wh·kg⁻¹ and 432 Wh·L⁻¹, respectively. This work expands the application boundaries of bulk lignocellulose pulp in advanced energy storage systems.