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Lithium‐metal anodes (LMAs) are the ultimate choice for realizing high‐energy‐density batteries; however, its use is hindered by problematic Li growth in the form of dendrites. To alleviate dendritic Li growth, the preparation of LMAs with a lithiophilic current collector (CC) is effective; however, applying a lithiophilic CC to LMAs is still challenging due to the manufacturing complexity involved in the separate lithiophilic treatment and lithiation processes. Herein, a facile one‐pot LMA fabrication method by utilizing thiourea (TU) as a precursor is proposed. A lithiophilic Cu2S layer is formed on Cu foam (CF) by the in situ electrochemical oxidation of TU (CuxSCF), and the lithiation of CC is performed via subsequent Li electrodeposition (Li@CuxSCF). The Cu2S on CuxSCF can lead to uniform Li deposition by providing lithiophilic sites, and it is converted to form ionic‐conductive Li2S‐rich solid electrolyte interphase layer. Resultantly, CuxSCF significantly enhances the cycling performance of LMAs compared to CF. Specifically, a LiFePO4/Li@CuxSCF full‐cell lithium‐metal battery (LMB) with a low n/p ratio (1.6) exhibits capacity retention of 95.6% at 0.5 C (220 cycles) and can maintain 85.0% of initial capacity (425 cycles, n/p = 4) at 2.0 C. LMBs with LiNi0.6Co0.2Mn0.2 and LiNi0.8Co0.1Mn0.1 also exhibit improved electrochemical performance.

All‐solid‐state Li‐metal battery (ASSLB) represents advantageous energy storage system for automotive applications. For ASSLB, inorganic solid electrolyte is essential in determining safety and cycling performance. However, significant challenges persist in practical construction of ASSLB with optimized electrolyte. Specifically, electrolyte's structural instability influencing its electrochemical performance remains critical issue within typical operating temperatures for ASSLB in electric vehicles. Herein, this challenge is fundamentally addressed by substituting trace amount of lithium with cadmium, which lacks crystal field stabilization energy. This strategy of atomic interaction modification has induced electrolyte's structural distortion and electronic alteration by deliberately introducing disorder at local lithium sites. Li symmetric cell with cadmium‐substituted antiperovskite solid electrolyte exhibits outstanding critical current density of 11.5 mA cm−2 (5.75 mAh cm−2) and excellent stability for 3000 h at 10.0 mA cm−2 (5.0 mAh cm−2). This study highlights explicit research direction for breakthrough of ASSLB, focusing on understanding how local distortion affects complex inorganic materials.

Lithium-sulfur (Li-S) battery is a promising energy storage system due to its cost effectiveness and high energy density. However, formation of Li dendrites from Li metal anode and shuttle effect of lithium polysulfides (LiPSs) from S cathode impede its practical application. Herein, ultrafine ZnS nanodots are uniformly grown on 2D MXene nanosheets by a low-temperature (60 °C) hydrothermal method for the first time. Distinctively, the ZnS nanodot-decorated MXene nanosheets (ZnS/MXene) can be easily filtered to be a flexible and freestanding film in several minutes. The ZnS/MXene film can be used as a current collector for Li-metal anode to promote uniform Li deposition due to the superior lithiophilicity of ZnS nanodots. ZnS/MXene powders obtained by freeze drying can be used as separator decorator to address the shuttle effect of LiPSs due to their excellent adsorbability. Theoretical calculation proves that the existence of ZnS nanodots on MXene can obviously improve the adsorption ability of ZnS/MXene with Li + and LiPSs. Li-S full cells with composite Li-metal anode and modified separator exhibit remarkable rate and cycling performance. Other transition metal sulfides (CdS, CuS, etc.) can be also grown on 2D MXene nanosheets by the low-temperature hydrothermal strategy., (© 2023 Wiley-VCH GmbH.)

Lithium (Li) metal anodes (LMAs) are promising anode candidates for realizing high-energy-density batteries. However, the formation of unstable solid electrolyte interphase (SEI) layers on Li metal is harmful for stable Li cycling; hence, enhancing the physical/chemical properties of SEI layers is important for stabilizing LMAs. Herein, thiourea (TU, CH 4 N 2 S) is introduced as a new catalyzing agent for LiNO 3 reduction to form robust inorganic-rich SEI layers containing abundant Li 3 N. Due to the unique molecular structure of TU, the TU molecules adsorb on the Cu electrode by forming CuS bond and simultaneously form hydrogen bonding with other hydrogen bonds accepting species such as NO 3 - and TFSI - through its NH bonds, leading to their catalyzed reduction and hence the formation of inorganic-rich SEI layer with abundant Li 3 N, LiF, and Li 2 S/Li 2 S 2 . Particularly, this TU-modified SEI layer shows a lower film resistance and better uniformity compared to the electrochemically and naturally formed SEI layers, enabling planar Li growth without any other material treatments and hence improving the cyclic stability in Li/Cu half-cells and Li@Cu/LiFePO 4  full-cells., (© 2023 Wiley-VCH GmbH.)

The anode plays a critical role relating to the energy density in all-solid-state lithium batteries (ASLBs). Silicon (Si) and lithium (Li) metal are two of the most attractive anodes because of their ultrahigh theoretical capacities. However, most investigations focus on Li metal, leaving the great potential of Si underrated. This work investigates the stability, processability, and cost of Si anodes in ASLBs and compares them with Li metal. Moreover, single-crystal LiNi 0.8 Mn 0.1 Co 0.1 O 2 is stabilized with lithium silicate (Li 2 SiO x ) through a scalable sol-gel method. ASLBs with a cell-level energy density of 285 Wh kg -1 are obtained by sandwiching the Si anode, the thin sulfide solid-state electrolyte membrane, and the interface stabilized LiNi 0.8 Mn 0.1 Co 0.1 O 2 . The full cell delivers a high capacity of 145 mAh g -1 at C/3 and maintains stability for 1000 cycles. This work inspires commercialization of ASLBs on a large scale with exciting manufacturing lines for large-scale, safe, and economical energy storage., (© 2022 Wiley-VCH GmbH.)

Uncontrolled lithium dendrite growth and dramatic volume change during cycling have long been severely impeding the practical applications of Li metal as the ultimate anode. In this work, ultrathin MgF 2 nanosheets encapsulated inside nitrogen-doped graphene-like hollow nanospheres (MgF 2 NSs@NGHSs) are ingeniously fabricated to address these problems by a perfect combination of atomic layer deposition and chemical vapor deposition. The uniform and continuous Li-Mg solid-solution inner layer formed by the MgF 2 nanosheets can reduce the nucleation overpotential and induce selective deposition of Li into the cavities of the NGHSs. Furthermore, the Li deposition behavior and mechanism of the hybrid host are comprehensively explored by in situ optical microscopy at the macroscopic level, in situ transmission electron microscopy at the microscopic level, and theoretical calculations at the atomic level, respectively. Benefiting from a synergistic modulation strategy of nanosheet seed-induced nucleation and Li-confined growth, the designed composite demonstrates an endurance of 590 cycles for asymmetric cells and a lifespan over 1330 h for corresponding symmetric cells. When applied in LiFePO 4 full cells, it provides a reversible capacity of 90.6 mAh g -1 after 1000 cycles at 1 C., (© 2022 Wiley-VCH GmbH.)

Integrating solid-state electrolyte (SSE) into Li-metal anodes has demonstrated great promise to unleash the high energy density of rechargeable Li-metal batteries. However, fabricating a highly cyclable SSE/Li-metal anode remains a major challenge because the densification of the SSE is usually incompatible with the reactive Li metal. Here, a liquid-metal-derived hybrid solid electrolyte (HSE) is proposed, and a facile transfer technology to construct an artificial HSE on the Li metal is reported. By tuning the wettability of the transfer substrates, electron- and ion-conductive liquid metal is sandwiched between electron-insulating and ion-conductive LiF and oxides to form the HSE. The transfer technology renders the HSE continuous, dense, and uniform. The HSE, having high ion transport, electron shut-off, and mechanical strength, makes the composite anode deliver excellent cyclability for over 4000 h at 0.5 mA cm -2 and 1 mAh cm -2 in a symmetrical cell. When pairing with LiFePO 4 and sulfur cathodes, the HSE-coated Li metal dramatically enhances the performance of full cells. Therefore, this work demonstrates that tuning the interfacial wetting properties provides an alternate approach to build a robust solid electrolyte, which enables highly efficient Li-metal anodes., (© 2022 Wiley-VCH GmbH.)

The solid electrolyte interphase (SEI) dictates the cycling stability of lithium-metal batteries. Here, direct atomic imaging of the SEI's phase components and their spatial arrangement is achieved, using ultralow-dosage cryogenic transmission electron microscopy. The results show that, surprisingly, a lot of the deposited Li metal has amorphous atomic structure, likely due to carbon and oxygen impurities, and that crystalline lithium carbonate is not stable and readily decomposes when contacting the lithium metal. Lithium carbonate distributed in the outer SEI also continuously reacts with the electrolyte to produce gas, resulting in a dynamically evolving and porous SEI. Sulfur-containing additives cause the SEI to preferentially generate Li 2 SO 4 and overlithiated lithium sulfate and lithium oxide, which encapsulate lithium carbonate in the middle, limiting SEI thickening and enhancing battery life by a factor of ten. The spatial mapping of the SEI gradient amorphous (polymeric → inorganic → metallic) and crystalline phase components provides guidance for designing electrolyte additives., (© 2021 Wiley-VCH GmbH.)

An artificial lithium-nitrate (LiNO 3 )-rich layer (LN-RL) is developed to address dendritic lithium (Li) growth by a fusing-infusing strategy, in which LiNO 3 is loaded into stainless steel mesh and a Li-metal anode (LN-RL@Li) is obtained by casting this LN-RL onto Li foil. The LN-RL enables fast Li deposition kinetics in carbonates and endows LN-RL@Li with excellent cycleability. The underneath mechanism on the contribution of LN-RL is uncovered by detailed characterizations combining with theoretical simulations. The LN-RL promotes the desolvation and capacitive adsorption of Li ions and induces in-plane Li growth along the edges of preplated Li with planar morphology. The improved cycleability of LN-RL(@Li) is demonstrated by LiǁCu cell that presents a coulombic efficiency of 97.2% after 280 cycles and LiǁLi cell that proceeds over 1000 h at 0.5 mA cm -2 in carbonates. Additionally, the LiǁLiFePO 4 cell shows a capacity retention of 58% after 400 cycles at 1 C (1 C = 170 mA g -1 ), compared to the 35% after 180 cycles for the control. This work presents not only a promising strategy for practical applications of Li-metal batteries, but also a new understanding on the role of nitrate in Li plating/stripping kinetics., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Uncontrollable growth of Li dendrites and low utilization of active Li severely hinder its practical application. Construction of an artificial solid electrolyte interphase (SEI) on Li is demonstrated as one of the most effective ways to circumvent the above problems. Herein, a novel spray quenching method is developed in situ to fabricate an organic-inorganic composite SEI on Li metal. By spray quenching molten Li in a modified ether-based solution, a homogeneous and dense SEI consisting of organic matrix embedded with inorganic LiF and Li 3 N nanocrystallines (denoted as OIFN) is constructed on Li metal. Arising from high ionic conductivity and strong mechanical stability, the OIFN can not only effectively minimize the corrosion reaction of Li, but also greatly suppresses the dendrite growth. Accordingly, the OIFN-Li anode presents prominent electrochemical performance with an enhanced Coulombic efficiency of 98.15% for 200 cycles and a small hysteresis of <450 mV even at ultrahigh current density up to 10 mA cm -2 . More importantly, during the full cell test with limited Li source, a high utilization of Li up to 40.5% is achieved for the OIFN-Li anode. The work provides a brand-new route to fabricate advanced SEI on alkali metal for high-performance alkali-metal batteries., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The key bottlenecks hindering the practical implementations of lithium-metal anodes in high-energy-density rechargeable batteries are the uncontrolled dendrite growth and infinite volume changes during charging and discharging, which lead to short lifespan and catastrophic safety hazards. In principle, these problems can be mitigated or even solved by loading lithium into a high-surface-area, conductive, and lithiophilic porous scaffold. However, a suitable material that can synchronously host a large loading amount of lithium and endure a large current density has not been achieved. Here, a lithiophilic 3D nanoporous nitrogen-doped graphene as the sought-after scaffold material for lithium anodes is reported. The high surface area, large porosity, and high conductivity of the nanoporous graphene concede not only dendrite-free stripping/plating but also abundant open space accommodating volume fluctuations of lithium. This ingenious scaffold endows the lithium composite anode with a long-term cycling stability and ultrahigh rate capability, significantly improving the charge storage performance of high-energy-density rechargeable lithium batteries., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The Li-O 2 battery (LOB) is considered as a promising next-generation energy storage device because of its high theoretic specific energy. To make a practical rechargeable LOB, it is necessary to ensure the stability of the Li anode in an oxygen atmosphere, which is extremely challenging. In this work, an effective Li-anode protection strategy is reported by using boric acid (BA) as a solid electrolyte interface (SEI) forming additive. With the assistance of BA, a continuous and compact SEI film is formed on the Li-metal surface in an oxygen atmosphere, which can significantly reduce unwanted side reactions and suppress the growth of Li dendrites. Such an SEI film mainly consists of nanocrystalline lithium borates connected with amorphous borates, carbonates, fluorides, and some organic compounds. It is ionically conductive and mechanically stronger than conventional SEI layer in common Li-metal-based batteries. With these benefits, the cycle life of LOB is elongated more than sixfold., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Bendable energy-storage systems with high energy density are demanded for conformal electronics. Lithium-metal batteries including lithium-sulfur and lithium-oxygen cells have much higher theoretical energy density than lithium-ion batteries. Reckoned as the ideal anode, however, Li has many challenges when directly used, especially its tendency to form dendrite. Under bending conditions, the Li-dendrite growth can be further aggravated due to bending-induced local plastic deformation and Li-filaments pulverization. Here, the Li-metal anodes are made bending tolerant by integrating Li into bendable scaffolds such as reduced graphene oxide (r-GO) films. In the composites, the bending stress is largely dissipated by the scaffolds. The scaffolds have increased available surface for homogeneous Li plating and minimize volume fluctuation of Li electrodes during cycling. Significantly improved cycling performance under bending conditions is achieved. With the bending-tolerant r-GO/Li-metal anode, bendable lithium-sulfur and lithium-oxygen batteries with long cycling stability are realized. A bendable integrated solar cell-battery system charged by light with stable output and a series connected bendable battery pack with higher voltage is also demonstrated. It is anticipated that this bending-tolerant anode can be combined with further electrolytes and cathodes to develop new bendable energy systems., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

High-energy lithium-metal batteries are among the most promising candidates for next-generation energy storage systems. With a high specific capacity and a low reduction potential, the Li-metal anode has attracted extensive interest for decades. Dendritic Li formation, uncontrolled interfacial reactions, and huge volume effect are major hurdles to the commercial application of Li-metal anodes. Recent studies have shown that the performance and safety of Li-metal anodes can be significantly improved via organic electrolyte modification, Li-metal interface protection, Li-electrode framework design, separator coating, and so on. Superior to the liquid electrolytes, solid-state electrolytes are considered able to inhibit problematic Li dendrites and build safe solid Li-metal batteries. Inspired by the bright prospects of solid Li-metal batteries, increasing efforts have been devoted to overcoming the obstacles of solid Li-metal batteries, such as low ionic conductivity of the electrolyte and Li-electrolyte interfacial problems. Here, the approaches to protect Li-metal anodes from liquid batteries to solid-state batteries are outlined and analyzed in detail. Perspectives regarding the strategies for developing Li-metal anodes are discussed to facilitate the practical application of Li-metal batteries., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Substantial efforts are underway to develop all-solid-state Li batteries (SSLiBs) toward high safety, high power density, and high energy density. Garnet-structured solid-state electrolyte exhibits great promise for SSLiBs owing to its high Li-ion conductivity, wide potential window, and sufficient thermal/chemical stability. A major challenge of garnet is that the contact between the garnet and the Li-metal anodes is poor due to the rigidity of the garnet, which leads to limited active sites and large interfacial resistance. This study proposes a new methodology for reducing the garnet/Li-metal interfacial resistance by depositing a thin germanium (Ge) (20 nm) layer on garnet. By applying this approach, the garnet/Li-metal interfacial resistance decreases from ≈900 to ≈115 Ω cm 2 due to an alloying reaction between the Li metal and the Ge. In agreement with experiments, first-principles calculation confirms the good stability and improved wetting at the interface between the lithiated Ge layer and garnet. In this way, this unique Ge modification technique enables a stable cycling performance of a full cell of lithium metal, garnet electrolyte, and LiFePO 4 cathode at room temperature., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The formation of lithium dendrites induces the notorious safety issue and poor cycling life of energy storage devices, such as lithium-sulfur and lithium-air batteries. We propose a surface energy model to describe the complex interface between the lithium anode and electrolyte. A universal strategy of hindering formation of lithium dendrites via tuning surface energy of the relevant thin film growth is suggested. The merit of the novel motif lies not only fundamentally a perfect correlation between electrochemistry and thin film fields, but also significantly promotes larger-scale application of lithium-sulfur and lithium-air batteries, as well as other metal batteries (e.g., Zn, Na, K, Cu, Ag, and Sn).