Tailored Organic Cathode Material with Multi‐Active Site and Compatible Groups for Stable Quasi‐Solid‐State Lithium‐Organic Batteries

Abstract

Quasi‐solid‐state lithium‐organic batteries have attracted widespread attention in view of their high safety, good mechanical strength, compromise ionic conductivity, and environmental friendliness. However, most organic electrode materials suffer from the undesirable interfacial compatibility, thus causing poor cycling stability. Herein, a quinone‐fused aza‐phenazine (THQAP) is reported with multi‐active site and compatible groups as the cathode material for constructing poly(vinylidene fluoride hexafluoro propylene) (PVDF‐HFP)‐based quasi‐solid‐state lithium‐organic batteries. Benefitting from the high compatibility between cathode material (THQAP) and gel polymer electrolytes (PVDF‐HFP), the dissolution and shuttle reaction of THQAP with hydroxyl groups are suppressed compared with its counterparts (QAP) without hydroxyl groups. As a result, THQAP in quasi‐solid‐state lithium‐organic batteries not only delivers excellent reversible capacity of 240 mAh g−1 at 50 mA g−1, but also exhibits stable cyclability with capacity retention of 78% (160 mAh g−1) after 200 cycles at 200 mA g−1. This study offers a promising strategy to develop quasi‐solid‐state lithium‐organic batteries with higher capacity and cycling stability.

“Like Compatible Like” Strategy Designing Strong Cathode‐Electrolyte Interface Quasi‐Solid‐State Lithium–Sulfur Batteries

“…The decrease in the local electron density near the hydrogen atom in the O─H group and the increase in the local electron density of both the oxygen atom in the C═O group and the nitrogen atom in the N‐H group, which clearly demonstrates the strong H‐bonding between them. [ 41 ] These indicate that the O─H introduced through the reaction of PEI and GMA can participate in the formation of H‐bonding, which in turn effectively enhances the interfacial compatibility between the polar organosulfur polymer cathode and the polar GPE, and constructs a strong cathode‐electrolyte interface. In contrast, the polarity differences and weak interactions between the nonpolar G/S and the polar GPE lead to the instability of the interface, which in turn affects the electrochemical performance (Figure 5g).…”

Solid-state electrolytes for inhibiting active species crossover in lithium metal batteries: a review

“…7(g), quinone-fused aza-phenazine (THQAP) is compatible with poly(vinylidene fluoride hexafluoro propylene) (PVDF-HFP) based polymer electrolytes. 100 The hydroxyl groups in THQAP and F of PVDF-HFP can form hydrogen bonds which could inhibit the dissolution of THQAP.…”

A Pyrazine‐Based 2D Conductive Metal‐Organic Framework for Efficient Lithium Storage†

“…[ 10 ] Recently, organic molecules containing redox active units such as disulfide, imide, aromatic azo and organic radical have emerged as an alternative to transition‐metal oxide cathodes, due to their merits of flexible structure, rich sources, and environmental friendliness. [ 11‐16 ] Despite these advantages, organic materials typically suffer from partial dissolution in the electrolytes as well as low intrinsic conductivity, resulting in limited lifetime and low rate performance. [ 11 ]…”