A Multifunctional Conductive Binder Network Stabilizing Black Phosphorus Anodes for Long‐Cycle‐Life Lithium‐Ion Batteries

Abstract Black phosphorus (BP) is a highly promising anode material for lithium‐ion batteries, boasting an exceptional theoretical capacity (2596 mAh g −1 ), a suitable lithiation potential (0.7 V vs Li + /Li), and favorable ion diffusion kinetics. However, its practical application is hampered by substantial volume expansion during cycling and the dissolution of soluble lithium polyphosphides (Li x Ps), leading to rapid capacity decay and poor cycling stability. To mitigate these issues, a novel 3D conductive polymer binder, denoted as “CP‐Si”; is developed. This binder is synthesized through in situ polymerization of poly( 3,4 ‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) using a silane‐functionalized carboxymethyl cellulose template. The CP‐Si network establishes robust cross‐linking via strong electrostatic and hydrogen‐bonding interactions, which significantly enhances the electrode's mechanical integrity and facilitates efficient electron transport. Furthermore, the abundant polar functional groups within CP‐Si effectively chemisorb Li x Ps intermediates, suppressing their shuttling and promoting the formation of a stable solid electrolyte interphase. As a result, the BP‐based anodes with the CP‐Si binder delivers outstanding long‐cycle performance, retaining a high reversible capacity of 741.0 mAh g −1 after 3000 cycles at a high current density of 2.0 A g −1 . This work provides a fundamental design strategy for multifunctional binders, paving the way for high‐performance, next‐generation energy storage devices.