Revealing the reversible solid-state electrochemistry of lithium-containing conjugated oximates for organic batteries

Abstract

In the rising advent of organic Li-ion positive electrode materials with increased energy content, chemistries with high redox potential and intrinsic oxidation stability remain a challenge. Here, we report the solid-phase reversible electrochemistry of the oximate organic redox functionality. The disclosed oximate chemistries, including cyclic, acyclic, aliphatic, and tetra-functional stereotypes, uncover the complex interplay between the molecular structure and the electroactivity. Among the exotic features, the most appealing one is the reversible electrochemical polymerization accompanying the charge storage process in solid phase, through intermolecular azodioxy bond coupling. The best-performing oximate delivers a high reversible capacity of 350 mAh g −1 at an average potential of 3.0 versus Li + /Li 0 , attaining 1 kWh kg −1 specific energy content at the material level metric. This work ascertains a strong link between electrochemistry, organic chemistry, and battery science by emphasizing on how different phases, mechanisms, and performances can be accessed using a single chemical functionality.

Impact of the Microstructure on Electrochemical Performances of Dilithium Benzoquinone Dioximate as a Positive Material for a Li-Ion Battery

“…By investigating them closely, some small, rounded grains (∼5−25 nm) can be distinguished and seem to be "glued" to the big particles. These observations are consistent with a growth process and most probably here with a progressive polymerization of small organic grains as proposed by Wang et al 13 The SAED pattern obtained on the large particles present a dots pattern (see inset in Figure 5b), which is characteristic of monocrystalline sample and the indexation of the direction can be in accord with (00l) interplanar distance from PNND (Figure S11b). 19 The chemical characterizations obtained by EELS showed the absence of contribution in the Li K-edge (Figure S13a, black dot line) and the presence of white lines in the C K-edge and N K-edge (Figure S13b, black dot line) confirming that the crystalline area was the active material and the complete lithium deinsertion after the charge process.…”

“…Very recently, an electroactive molecule, easily synthesized by the action of hydroxyl amine on p-benzoquinone, was revealed as solid-state positive electrode for Li-ion batteries. 13 In this work, five lithiated dioxime (lithium dioximate) have been investigated and exhibited interesting electrochemical performance with redox around 2.5−3.2 V vs Li + /Li and capacity in the range of 210−360 mAh g −1 . In addition to the electrochemistry investigation, this work elucidated the redox mechanism of this class of compounds thanks to an ex-situ infrared study and by using the diffraction technique to understand the role of the crystalline structure.…”

“…Very recently, an electroactive molecule, easily synthesized by the action of hydroxyl amine on p -benzoquinone, was revealed as solid-state positive electrode for Li-ion batteries . In this work, five lithiated dioxime (lithium dioximate) have been investigated and exhibited interesting electrochemical performance with redox around 2.5–3.2 V vs Li + /Li and capacity in the range of 210–360 mAh g –1 .…”

Reliable Organic Carbonyl Electrode Materials Enabled by Electrolyte and Interfacial Chemistry Regulation

“…Optimizing the types and proportions of salts, solvents, and/or additives could reach this goal. In addition to carbonyl electrode materials, these design strategies may be extended to other promising organic electrode materials such as lithium-containing conjugated sulfonamides and oximates to enhance their electrochemical performance. , …”

An Investigation of Conjugated Sulfonamide Materials as Binders for Organic Lithium-Ion Batteries

“…Sulfonamide-based small molecules have been recently investigated as stable electrolytes for lithium–sulfur, lithium–oxygen, − and high voltage lithium-ion batteries − and as additives for zinc ion batteries, highlighting the potential for sulfonamide groups to facilitate ion conduction. More recently, aromatic sulfonamides have been utilized as a novel organic cathode material for metal-ion batteries − and as ion conductors in solid-state electrolytes. , These encouraging results provide motivation to further investigate sulfonamides as a part of functional binder additives toward ongoing energy application research.…”