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Anode‐free lithium (Li) metal batteries (AFLBs) featured high energy density are viewed as the viable future energy storage technology. However, the irregular Li deposition and unstable solid electrolyte interphase (SEI) on anode current collectors reduce their cycling performance. Here, we propose a concept of anion‐recognition electrodes enabled by anion‐π interactions to regulate the inner Helmholtz plane (IHP) and electrolyte solvation chemistry for high‐performance AFLBs. By engineering the electrodes with electron‐deficient aromatic‐π systems that possess high permanent quadrupole moment (Qzz), the anion‐π interactions can be generated to concentrate the anions on the electrode surface and tune the IHP structure to construct a stable anion‐derived SEI layer, thus achieving highly reversible Li plating/stripping process. Through designing various current collectors with different Qzz values, the intimate correlations among the surface charge of the electrode, competitive adsorption of the IHP, and SEI structures are demonstrated. Particularly, the modified carbon cloth current collector with a high Qzz value (+35.1) delivers a high average Li stripping/plating Coulombic efficiency of 99.1 % over 230 cycles in the carbonated electrolyte, enabling a long lifespan and high capacity retention of LiNi0.8Co0.1Mn0.1O2‐based AFLBs with a commercial‐level areal capacity (4.1 mAh cm−2). [ABSTRACT FROM AUTHOR]

The structures and properties of the electric double layer (EDL) on zinc (Zn) anodes significantly influence the cycling and rate performance of aqueous Zn batteries (ZBs). Here, a strategy is reported to regulate the EDL structure through work function (Wf) engineering to effectively enhance the electrochemical performance of ZBs, which is enabled by electrolyte‐tailored growth of heterogenous metal with a large Wf on the Zn anode. The metal‐to‐metal charge transfer in heterostructured Zn metal induced by the disparity of Wf increases the surface charge density, which enriches the Zn ions and shortens the thickness of EDL. The compressed EDL weakens the repulsive force of Zn deposits to achieve a tightly stacked and dendrite‐free Zn deposition. Besides, the formed H2O‐deficient EDL structure enables the inorganic‐rich solid electrolyte interphase (SEI) with high Zn‐ion conductivity to inhibit the notorious parasitic reactions and improve the electrode reaction kinetics. Consequently, the Zn||Zn symmetric cells demonstrate an ultra‐long cycling life over 2700 cycles (the cumulative capacity reaches 5400 mA h cm−2) at a high current density of 50 mA cm−2. The Zn anodes show a high average Coulombic efficiency of 99.70% over 3650 cycles. The Zn||MnO2 full cells exhibit excellent practical‐level performance under cyclic continuous mode (3000‐cycle life at high rates) and cyclic intermittent mode (1170‐cycle life with 83.05% capacity retention). Practical pouch cells are also demonstrated with outstanding cycling performance. [ABSTRACT FROM AUTHOR]

Anode‐free lithium (Li) metal batteries (AFLBs) featured high energy density are viewed as the viable future energy storage technology. However, the irregular Li deposition and unstable solid electrolyte interphase (SEI) on anode current collectors reduce their cycling performance. Here, we propose a concept of anion‐recognition electrodes enabled by anion‐π interactions to regulate the inner Helmholtz plane (IHP) and electrolyte solvation chemistry for high‐performance AFLBs. By engineering the electrodes with electron‐deficient aromatic‐π systems that possess high permanent quadrupole moment (Qzz), the anion‐π interactions can be generated to concentrate the anions on the electrode surface and tune the IHP structure to construct a stable anion‐derived SEI layer, thus achieving highly reversible Li plating/stripping process. Through designing various current collectors with different Qzz values, the intimate correlations among the surface charge of the electrode, competitive adsorption of the IHP, and SEI structures are demonstrated. Particularly, the modified carbon cloth current collector with a high Qzz value (+35.1) delivers a high average Li stripping/plating Coulombic efficiency of 99.1 % over 230 cycles in the carbonated electrolyte, enabling a long lifespan and high capacity retention of LiNi0.8Co0.1Mn0.1O2‐based AFLBs with a commercial‐level areal capacity (4.1 mAh cm−2). [ABSTRACT FROM AUTHOR]

The O3‐type Li‐rich layered oxides (LLOs) are approaching industrial applications as high‐energy cathode materials for Li‐ion batteries (LIBs), however, they suffer from rapid performance decay associated with oxygen activities. The interplay between surface and bulk transformations in LLOs, especially the electrochemical behaviors of oxygen anions, remains elusive. Here, by regulating the surface of an O3‐type LLO (Li1.13Mn0.517Ni0.256Co0.097O2) using an all‐fluorinated electrolyte, an enhanced capacity retention from 57.4% to 85.3% and a suppressed voltage decay from 1.34 mV cycle−1 to 0.58 mV cycle−1 within 300 cycles are realized. The performance enhancement is attributed to the thin, uniform, robust, and compact F‐rich cathode‐electrolyte interphase (CEI), which suppresses various types of oxygen‐related surface degradation and, more importantly, stabilizes the bulk oxygen reactions. Through the combined experimental and theoretical studies, this work directly reveals the intriguing association between the surface and bulk oxygen activities and demonstrates that optimizing the interphase is an effective approach for improving the stability of high‐energy battery cathodes involving oxygen redox reactions. [ABSTRACT FROM AUTHOR]

High‐energy‐density Li‐rich layered oxides (LLOs) as promising cathodes for Li‐ion batteries suffer from the dissolution of transition metals (especially manganese) and severe side reactions in conventional electrolytes, which greatly deteriorate their electrochemical performance. Herein, an in situ "anchoring + pouring" synergistic cathode–electrolyte interphase (CEI) construction is realized by using 1,3,6‐hexanetricarbonitrile (HTCN) and tris(trimethylsilyl) phosphate (TMSP) electrolyte additives to alleviate the challenges of an LLO (Li1.13Mn0.517Ni0.256Co0.097O2). HTCN with three nitrile groups can tightly anchor transition metals by coordinative interaction to form the CEI framework, and TMSP will electrochemically decompose to reshape the CEI layer. The uniform and robust in situ constructed CEI layer can suppress the transition metal dissolution, shield the cathode against diverse side reactions, and significantly improve the overall electrochemical performance of the cathod with a discharge voltage decay of only 0.5 mV cycle−1. Further investigations based on a series of experimental techniques and theoretical calculations have revealed the composition of in situ constructed CEI layers and their distribution, including the enhanced HTCN anchoring effect after lattice densification of LLOs. This study provides insights into the in situ CEI construction for enhancing the performance of high‐energy and high‐voltage cathode materials through effective, convenient, and economical electrolyte approaches. [ABSTRACT FROM AUTHOR]

The fast-charging capability of rechargeable batteries is greatly limited by the sluggish ion transport kinetics in anode materials. Here we develop an iodized polyacrylonitrile (I-PAN) anode that can boost the bulk/interphase lithium (Li)-ion diffusion kinetics and accelerate Li-ion desolvation process to realize high-performance fast-charging Li-ion batteries. The iodine immobilized in I-PAN framework expands ion transport channels, compresses the electric double layer, and changes the inner Helmholtz plane to form LiF/LiI-rich solid electrolyte interphase layer. The dissolved iodine ions in the electrolyte self-induced by the interfacial nucleophilic substitution of PF 6 - not only promote the Li-ion desolvation process, but also reuse the plated/dead Li formed on the anode under fast-charging conditions. Consequently, the I-PAN anode exhibits a high capacity of 228.5 mAh g -1 (39 % of capacity at 0.5 A g -1 delivered in 18 seconds) and negligible capacity decay for 10000 cycles at 20 A g -1 . The I-PAN||LiNi 0.8 Co 0.1 Mn 0.1 O 2 full cell shows excellent fast-charging performance with attractive capacities and negligible capacity decay for 1000 cycles at extremely high rates of 5 C and 10 C (1 C=180 mA g -1 ). We also demonstrate high-performance fast-charging sodium-ion batteries using I-PAN anodes., (© 2023 Wiley-VCH GmbH.)