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LiNO3 is an effective additive for improving the performance of Li metal anodes. However, the practical application of LiNO3 is limited due to its poor solubility. Here, a novel electrolyte additive of MgAl layered double hydroxides (LDHs) with open interlayered anionic vacancies is proposed. The electropositive MgAl LDHs promote the spontaneous coordination of NO3− into anionic vacancies of LDH interlayers via memory effect, rehydrating to original NO3−‐MgAl LDHs structure and accelerating LiNO3 dissolution. The reconstructed NO3−‐MgAl LDHs play a crucial role as sustainable nitrate resources, preventing partial NO3− from participating in the Li+ solvent sheath to reduce the solvation binding energy. Moreover, MgAl LDHs absorb the anions due to electrostatic attraction, accounting for more dissociated Li+ and active Li+ migration in carbonate electrolytes. NO3− stored in MgAl LDHs is also preferentially reduced to form Li3N‐rich solid electrolyte interphase (SEI), decreasing the activation energy barrier for Li+ transport and striving to form a uniform Li deposition. The cells assembled with MgAl LDHs and LiNO3 additives deliver high Coulombic efficiency, excellent rate capability, and high capacity retention. This strategy provides new insights into LiNO3‐promotor design and excavates the potential of LDHs materials for Li metal batteries. [ABSTRACT FROM AUTHOR]

The rampant dendrites and hydrogen evolution reaction (HER) resulting from the turbulent interfacial evolution at the anode/electrolyte are the main culprits of short lifespan and low Coulombic efficiency of Zn metal batteries. In this work, a versatile protective coating with excellent zincophilic and amphoteric features is constructed on the surface of Zn metal (ZP@Zn) as dendrite‐free anodes. This kind of protective coating possesses the advantages of reversible proton storage and rapid desolvation kinetics, thereby mitigating the HER and facilitating homogeneous nucleation concomitantly. Furthermore, the space charge polarization effect promotes charge redistribution to achieve uniform Zn deposition. Accordingly, the ZP@Zn symmetric cell manifests excellent reversibility at an ultrahigh cumulative plating capacity of 4700 mAh cm−2 and stable cycling at 80 % depth of discharge (DOD). The ZP@Zn//V6O13 pouch cell also reveals superior cycling stability with a high capacity of 326.6 mAh g−1. [ABSTRACT FROM AUTHOR]

Carbonate‐based electrolytes are incompatible with lithium (Li) metal anode because the generated solid electrolyte interphase (SEI) undergoes repeated breakage‐repair, resulting in the accumulation of inactive Li including Li+ compounds and electrically isolated dead Li0 in the SEI. Therefore, exploiting a suitable strategy to construct a stable SEI while efficiently rejuvenating the inactive Li capacity is urgent and more thoughtful than just building a stereotyped SEI layer. Herein, an innovative strategy is proposed of high‐concentration additive (HCA) of LiNO3 inspired by (localized) high‐concentration electrolyte and inactive Li restoration methodology via triiodide/iodide (I3−/I−) redox couple to improve the compatibility of carbonate‐based electrolytes. The HCA of LiNO3 can maintain the cation–anion aggregates solvation structures in the carbonate‐based bulk electrolyte and induce the in situ formation of superior‐ionic‐conductivity NO3−‐derived SEI. Moreover, the reversible I3−/I− redox couple can further optimize the SEI and constantly rejuvenate the inactive Li including solvent/LiNO3‐derived Li2O, a derivative has almost been acquiescent in LiNO3‐additive electrolytes, and dead Li0 into delithiated cathode. Consequently, epitaxy‐like planar Li deposition, better reversibility, and higher capacity retention can be realized and are systematically verified by Li||Cu half cells, full cells with excess/limited Li (N/P ratio = 1.5) and anode‐free lithium metal batteries. [ABSTRACT FROM AUTHOR]

It is widely recognized that SiOx is a feasible anode material for the next generation lithium‐ion batteries because of its high capacity, low cost, environmental friendliness, and abundant available storage. However, the enormous volume expansion and irreversible by‐products during lithiation can result in the rapid capacity degradation and low coulombic efficiency. The commercial binders of carboxymethyl cellulose (CMC) and polyvinylidene difluoride cannot afford the volume change. Herein, a rational crosslinked binder is synthesized through an in situ condensation reaction between CMC and phthalic acid (PA). With rich hydroxyl groups bonded to the homogeneous SiO2 nanodomain, the enormous volume expansion of the SiOx anode can be restricted efficaciously. Therefore, the SiOx@CMC‐PA electrode delivers a reversible specific capacity of 671 mAh g−1 at 500 mA g−1 after 200 cycles and a high average coulombic efficiency of 99.2%, much higher than 226.3 mAh g−1 of SiOx@CMC electrode. It demonstrates that this work offers a cost effective and available strategy to achieve high performance binder for Si‐based anode materials. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surficial CuO modification enhances Li affinity of Ni foam for easy thermal infusion. • The influence of different morphologies of CuO on guiding Li plating/stripping behavior is investigated. • CuO nanoneedle arrays can overcome the nucleation barrier and redistribute the Li+ flux. • The composite electrode delivers outstanding electrochemical performances. Undesirable dendrite growth and infinite volume expansion are the major barriers to the potential application for next-generation safe Li metal batteries. To solve these problems, we herein report electroplating CuO nanoneedle arrays on Ni foam (NCNF) as 3D porous framework for Li metal batteries. The influence of different morphologies of CuO on guiding Li plating/stripping behavior has been investigated. The homogenous deposition of Li can be attributed to the interspace between the CuO nanoneedles, which is remarkably superior over granular CuO on Ni foam (GCNF) at high areal capacity. The hierarchical skeleton can not only decrease local current inhomogeneity but also alleviate the volume change of Li. The NCNF electrode delivers a higher Coulombic efficiency of Li deposition comparing with the bare Ni foam and GCNF. Furthermore, enhanced cycling stability with small overpotential can be achieved in symmetric cells. In a Li/LiFePO 4 full cell, the excellent cycling performance also proves the superiority of NCNF@Li composite electrode. [ABSTRACT FROM AUTHOR]

Highlights: [•] Co(OH)2 hexagonal nanosheets can be prepared via a facile microwave-assisted route. [•] Porous Co3O4 nanosheets can be obtained via the calcination of Co(OH)2 nanosheets. [•] The stability and high capacity enable them to be potential candidate for LIB anode. [ABSTRACT FROM AUTHOR]

Silicon (Si) has attracted intensive academic and commercial attention due to its extremely high theoretical capacity. However, it is still far away from practical application because of its fast capacity fading, which is caused by the huge volume change. Here, a novel network polymer binder is synthesized through in situ thermal crosslinking of water‐soluble carboxymethyl cellulose (CMC) and maleic anhydride (MAH). The as‐obtained polymer binder network can effectively restrict the huge volume change of Si anodes upon lithiation. Because of the significantly enhanced structural stability, the Si anodes with network polymer binder deliver enhanced electrochemical performance, with a capacity of 996 mAh g−1 at a high current density of 1 A g−1 after 120 cycles under high mass loading. Most importantly, a high average Coulomb efficiency (CE) of 99.4% is obtained, which is superior over the average CE (98.7%) of Si only using CMC as binder. It is considered that this novel 3D network cross‐linking binder can be used for high‐capacity anode materials in next‐generation Li‐ion batteries. [ABSTRACT FROM AUTHOR]

Recent developments of transition metal selenides as potential anode materials for lithium-ion batteries (LIBs) have attracted much attention. In this work, NiSe 2 nanosheets grown on carbon fiber cloth (denoted as NiS 2 nanosheets/CFC) are successfully prepared via simple hydrothermal and subsequent annealing methods. When investigated as anode for LIBs, NiSe 2 nanosheets/CFC exhibits high reversible capacities of 1196 mA h g−1 after 100 cycles at 0.1 A g−1, 811 mA h g−1 after 150 cycles at 0.5 A g−1, corresponding to superior capacity retention of 94%. Besides, a high-rate capability of 682 mA h g−1 at 2 A g−1 is also achieved. The excellent electrochemical performance of NiSe 2 nanosheets/CFC is mainly derived from the good electrical conductivity of carbon fiber cloth (CFC), the increased active-surface area and fast Li+ diffusion caused by the nanosheets structure with particle packing. Therefore, NiSe 2 nanosheets/CFC is anticipated to be a promising anode material for flexible Li-ion batteries. Image 1 • NiSe 2 nanosheets grown on CFC are successfully prepared. • NiSe 2 nanosheets/CFC exhibits a high capacity of 1196 mA h g−1 after 100 cycles at 0.1 A g−1. • The excellent electrochemical performance is mainly due to the good conductivity and the nanostructure. [ABSTRACT FROM AUTHOR]

Silicon (Si) is a promising high-capacity anode material for the next-generation of rechargeable lithium ion batteries (LIBs). Though there are formidable challenges from the large volumetric change during lithiation, well-designed nanostructure and reduced size of Si can remarkably alleviate the negative effects. Herein we apply a magnesiothermic reduction process to synthesize interconnected Si nanoparticles in large quantities. Earth abundant clay of halloysite with tubular structure has been used as silica precursor after acid washing. A high Si yield can be achieved upon pressing the precursor powder into a pallet before reduction. The obtained interconnected Si nanoparticles exhibit a high specific capacity of 3752.4 mA h g −1 for the first cycle at1 A g −1 and 1469.0 mA h g −1 after 400th cycles at current density of 3.5 A g −1 . Even tested at 5 A g −1 for 1000 cycles, a high capacity of 735.1 mA h g −1 is obtained. The rate capability is also evaluated and a high capacity of 1050 mA h g −1 is achieved at 10 A g −1 . [ABSTRACT FROM AUTHOR]