Self‐Polarized Organic–Inorganic Hybrid Ferroelectric Cathode Coatings Assisted High Performance All‐Solid‐State Lithium Battery

Abstract

Ferroelectrics can significantly boost electrochemical performances of all‐solid‐state batteries by constructing built‐in electric field to reduce the space charge layer at cathode/solid‐state electrolyte interface. However, the construction mechanism of ferroelectric built‐in electric field is poorly understood. Herein, the guanidinium perchlorate (GClO4) ferroelectrics as the cathode coatings in the LiCoO2‐based all‐solid‐state lithium battery are reported, which has state‐of‐the‐art specific capacity of 210.6 mAh g−1 (91.6% of the liquid battery). Systematic studies reveal that the flexoelectric effect originating from the lattice mismatch between GClO4 and LiCoO2 gives GClO4 coatings the single‐domain state and upward self‐polarization. Consequently, a vertically downward built‐in electric field is generated relative to the cathode, which transports the lithium ions inside the electrolyte to the three‐phase interface to alleviate the space charge layer. These findings highlight that the microstructural characteristics of ferroelectric and electrode materials are the primary concern for building an effective built‐in electric field.

Functional dielectric materials for high-performance solid-state batteries

“…Cui et al used an organic–inorganic hybrid ferroelectric material, guanidinium perchlorate (C(NH 2 ) 3 ClO 4 ), as an LCO cathode coating to investigate the effect of the built-in electric field in ferroelectric materials on the SCL. 83 The ferroelectricity of C(NH 2 ) 3 ClO 4 arises from the relative displacement between C(NH 2 ) 3 + and ClO 4 − . 84 C(NH 2 ) 3 ClO 4 crystallizes through the stacking of organic C(NH 2 ) 3 + and inorganic ClO 4 -linked by hydrogen bonds (Fig.…”

Polymer‐Based Solid‐State Electrolytes for High‐Energy‐Density Lithium‐Ion Batteries – Review

“…The total interfacial resistance of the LCO-BTO (mass-loading: 8.9 mg cm Besides the inorganic BTO and STO, the organic-inorganic hybrid ferroelectric guanidinium perchlorate (GClO 4 ) can also be used at the interfaces to prevent SCLs. [147] GClO 4 coating has a single-domain state with an upward self-polarization effect, creating a built-in electric field perpendicular to the cathode/electrolyte interface to alleviate the SCLs, as depicted in Figure 13c. The self-polarization was primarily attributed to the flexoelectric effect arising from the lattice mismatch between the GClO 4 coating and the LCO cathode.…”

“…Reproduced with permission. [147] Copyright 2023, John Wiley and Sons. d) Zn 2+ concentration distribution at the anode/electrolyte interface with different amounts of immobilized SO4 2− .…”

Accumulative Delocalized Mo 4d Electrons to Bound the Volume Expansion and Accelerate Kinetics in Mo6S8 Cathode for High-Performance Aqueous Cu2+ Storage

“…In terms of common wisdom, a dual composite strategy or Janus engineering could provide high-performance electrodes at the lattice structure and bonding structure levels, respectively. − To date, some explorations have been proposed for stable and fast multivalent ion storage, and these strategies involve surface coating, , nanoengineering, − superlattice structure, , heterojunction engineering, , and cathode electrolyte interface (CEI) layers . Lei et al prepared CuS 1– x @PANI heterojunction engineering with high ionic conductivities while alleviating volume expansion, which provides a convenient pathway for electron and ion transport and cycling stability .…”

“…In terms of common wisdom, a dual composite strategy or Janus engineering could provide high-performance electrodes at the lattice structure and bonding structure levels, respectively. 11−22 To date, some explorations have been proposed for stable and fast multivalent ion storage, and these strategies involve surface coating, 11,12 nanoengineering, 13−15 superlattice structure, 16,17 heterojunction engineering, 18,19 and cathode electrolyte interface (CEI) layers. 20 al.…”