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1.
The energetic chemical reaction between Zn(NO 3) 2 and Li is used to create a solid‐state interface between Li metal and Li 6.4La 3Zr 1.4Ta 0.6O 12 (LLZTO) electrolyte. This interlayer, composed of Zn, ZnLi x alloy, Li 3N, Li 2O, and other species, possesses strong affinities with both Li metal and LLZTO and affords highly efficient conductive pathways for Li + transport through the interface. The unique structure and properties of the interlayer lead to Li metal anodes with longer cycle life, higher efficiency, and better safety compared to the current best Li metal electrodes operating in liquid electrolytes while retaining comparable capacity, rate, and overpotential. All‐solid‐state Li||Li cells can operate at very demanding current–capacity conditions of 4 mA cm ?2–8 mAh cm ?2. Thousands of hours of continuous cycling are achieved at Coulombic efficiency >99.5 % without dendrite formation or side reactions with the electrolyte. 相似文献
2.
The application of Li anodes is hindered by dendrite growth and side reactions between Li and electrolyte, despite its high capacity and low potential. A simple approach for this challenge is now demonstrated. In our strategy, the garnet‐type Li 6.4La 3Zr 1.4Ta 0.6O 12 (LLZTO)‐based artificial solid–electrolyte interphase (SEI) is anchored on Cu foam by sintering the Cu foam coated with LLZTO particles. The heat treatment leads to the interdiffusion of Cu and Ta 2O 5 at the Cu/LLZTO interface, through which LLZTO layer is fixed on Cu foam. 3D structure lowers the current density, and meanwhile the SEI reduces the contact of Li and electrolyte. Furthermore, the anchoring construction can endure Li‐deposition‐induced volume change. Therefore, LLZTO‐modified Cu foam shows much improved Li plating/stripping performance, including long lifespan (2400 h), high rate (maximum current density of 20 mA cm ?2), high areal capacity (8 mA h cm ?2 for 100 cycles), and high efficiency (over 98 %). 相似文献
3.
The garnet electrolyte presents poor wettability with Li metal, resulting in an extremely large interfacial impedance and drastic growth of Li dendrites. Herein, a novel ultra-stable conductive composite interface (CCI) consisting of Li ySn alloy and Li 3N is constructed in situ between Li 6.4La 3Zr 1.4Ta 0.6O 12 (LLZTO) pellet and Li metal by a conversion reaction of SnN x with Li metal at 300 °C. The Li ySn alloy as a continuous and robust bridge between LLZTO and Li metal can effectively reduce the LLZTO/Li interfacial resistance from 4468.0 Ω to 164.8 Ω. Meanwhile, the Li 3N as a fast Li-ion channel can efficiently transfer Li ions and give their uniform distribution at the LLZTO/Li interface. Therefore, the Li/LLZTO@CCI/Li symmetric battery stably cycles for 1200 h without short circuit, and the all-solid-state high-voltage Li/LLZTO@CCI/LiNi 0.5Co 0.2Mn 0.3O 2 battery achieves a specific capacity of 161.4 mAh g −1 at 0.25 C with a capacity retention rate of 92.6 % and coulombic efficiency of 100.0 % after 200 cycles at 25 °C. 相似文献
4.
The garnet electrolyte presents poor wettability with Li metal, resulting in an extremely large interfacial impedance and drastic growth of Li dendrites. Herein, a novel ultra‐stable conductive composite interface (CCI) consisting of Li ySn alloy and Li 3N is constructed in situ between Li 6.4La 3Zr 1.4Ta 0.6O 12 (LLZTO) pellet and Li metal by a conversion reaction of SnN x with Li metal at 300 °C. The Li ySn alloy as a continuous and robust bridge between LLZTO and Li metal can effectively reduce the LLZTO/Li interfacial resistance from 4468.0 Ω to 164.8 Ω. Meanwhile, the Li 3N as a fast Li‐ion channel can efficiently transfer Li ions and give their uniform distribution at the LLZTO/Li interface. Therefore, the Li/LLZTO@CCI/Li symmetric battery stably cycles for 1200 h without short circuit, and the all‐solid‐state high‐voltage Li/LLZTO@CCI/LiNi 0.5Co 0.2Mn 0.3O 2 battery achieves a specific capacity of 161.4 mAh g ?1 at 0.25 C with a capacity retention rate of 92.6 % and coulombic efficiency of 100.0 % after 200 cycles at 25 °C. 相似文献
5.
Applying interlayers is the main strategy to address the large area specific resistance (ASR) of Li/garnet interface. However, studies on eliminating the Li 2CO 3 and LiOH interfacial lithiophobic contaminants are still insufficient. Here, thermal-decomposition vapor deposition (TVD) of a carbon modification layer on Li 6.75La 3Zr 1.75Ta 0.25O 12 (LLZTO) provides a contaminant-free surface. Owing to the protection of the carbon layer, the air stability of LLZTO is also improved. Moreover, owing to the amorphous structure of the low graphitized carbon (LGC), instant lithiation is achieved, and the ASR of the Li/LLZTO interface is reduced to 9 Ω cm 2. Lithium volatilization and Zr 4+ reduction are also controllable during TVD. Compared with its high graphitized carbon counterpart (HGC), the LGC-modified Li/LLZTO interface displays a higher critical current density of 1.2 mA cm −2, as well as moderate Li plating and stripping, which provides enhanced polarization voltage stability. 相似文献
6.
Applying interlayers is the main strategy to address the large area specific resistance (ASR) of Li/garnet interface. However, studies on eliminating the Li 2CO 3 and LiOH interfacial lithiophobic contaminants are still insufficient. Here, thermal‐decomposition vapor deposition (TVD) of a carbon modification layer on Li 6.75La 3Zr 1.75Ta 0.25O 12 (LLZTO) provides a contaminant‐free surface. Owing to the protection of the carbon layer, the air stability of LLZTO is also improved. Moreover, owing to the amorphous structure of the low graphitized carbon (LGC), instant lithiation is achieved, and the ASR of the Li/LLZTO interface is reduced to 9 Ω cm 2. Lithium volatilization and Zr 4+ reduction are also controllable during TVD. Compared with its high graphitized carbon counterpart (HGC), the LGC‐modified Li/LLZTO interface displays a higher critical current density of 1.2 mA cm ?2, as well as moderate Li plating and stripping, which provides enhanced polarization voltage stability. 相似文献
7.
Solid-state Li metal batteries (SSLMBs) have attracted considerable interests due to their promising energy density as well as high safety. However, the realization of a well-matched Li metal/solid-state electrolyte (SSE) interface remains challenging. Herein, we report g-C 3N 4 as a new interface enabler. We discover that introducing g-C 3N 4 into Li metal can not only convert the Li metal/garnet-type SSE interface from point contact to intimate contact but also greatly enhance the capability to suppress the dendritic Li formation because of the greatly enhanced viscosity, decreased surface tension of molten Li, and the in situ formation of Li 3N at the interface. Thus, the resulting Li-C 3N 4|SSE|Li-C 3N 4 symmetric cell gives a significantly low interfacial resistance of 11 Ω cm 2 and a high critical current density (CCD) of 1500 μA cm −2. In contrast, the same symmetric cell configuration with pristine Li metal electrodes has a much larger interfacial resistance (428 Ω cm 2) and a much lower CCD (50 μA cm −2). 相似文献
8.
Solid electrolytes which possess excellent lithium-ion conductivity and chemical compatibility with electrode materials are necessary for the commercialization of all-solid-state lithium batteries. However, a single solid electrolyte meeting above requirements is difficult. Consequently, the composite electrolytes have attracted more attention. In this paper, Li6PS5Cl–xLi6.5La3Zr1.5Ta0.5O12 (LLZTO) (x = 0, 2.5 wt%, 5 wt%, 10 wt%) composite electrolytes are prepared by a simple planetary grinding process. It has been found that adding an appropriate amount of LLZTO can increase the lithium-ion conductivity. At 30 °C, the lithium-ion conductivity increases from 2.6 × 10−4 S/cm (Li6PS5Cl) to 5.4 × 10−4 S/cm (Li6PS5Cl-5 wt% LLZTO). Besides, the addition of LLZTO to the Li6PS5Cl can influence the growth rate of the SEI. It has been shown that the SEI growth rate obeys a parabolic rate law, and the growth rates of Li6PS5Cl, Li6PS5Cl-2.5 wt% LLZTO, Li6PS5Cl-5 wt% LLZTO, and Li6PS5Cl-10 wt% LLZTO are 8.62, 3.53, 3.33, and 3.38 Ω/h1/2 at 60 °C, respectively. In lithium plating and stripping experiment, the voltage of symmetrical Li/Li6PS5Cl/Li cell suddenly drops to 0 V after cycling 39 h at 0.103 mA/cm2 (0.097 mAh/cm2). On the contrary, the Li/Li6PS5Cl–xLLZTO (x = 2.5 wt%, 5 wt%, 10 wt%)/Li symmetrical cell exhibits a stable voltage profile over 100 h at the same test conditions. The corresponding interfacial impedance of Li/Li6PS5Cl–xLLZTO (x = 2.5 wt%, 5 wt%, 10 wt%) remains stable after 10, 30, and 50 charge/discharge cycles. 相似文献
9.
Constructing efficient artificial solid electrolyte interface (SEI) film is extremely vital for the practical application of lithium metal batteries. Herein, a dense artificial SEI film, in which lithiophilic Zn/Li xZn y are uniformly but nonconsecutively dispersed in the consecutive Li +-conductors of Li xSiO y, Li 2O and LiOH, is constructed via the in situ reaction of layered zinc silicate nanosheets and Li. The consecutive Li +-conductors can promote the desolvation process of solvated-Li + and regulate the transfer of lithium ions. The nonconsecutive lithiophilic metals are polarized by the internal electric field to boost the transfer of lithium ions, and lower the nucleation barrier. Therefore, a low polarization of ≈50 mV for 750 h at 2.0 mA cm −2 in symmetric cells, and a high capacity retention of 99.2 % in full cells with a high lithium iron phosphate areal loading of ≈13 mg cm −2 are achieved. This work offers new sights to develop advanced alkali metal anodes for efficient energy storage. 相似文献
10.
Li−O 2 batteries with bis(trifluoromethanesulfonyl)imide-based ionic liquid (TFSI-IL) electrolyte are promising because TFSI-IL can stabilize O 2− to lower charge overpotential. However, slow Li + transport in TFSI-IL electrolyte causes inferior Li deposition. Here we optimize weak solvating molecule (anisole) to generate anisole-doped ionic aggregate in TFSI-IL electrolyte. Such unique solvation environment can realize not only high Li + transport parameters but also anion-derived solid electrolyte interface (SEI). Thus, fast Li + transport is achieved in electrolyte bulk and SEI simultaneously, leading to robust Li deposition with high rate capability (3 mA cm −2) and long cycle life (2000 h at 0.2 mA cm −2). Moreover, Li−O 2 batteries show good cycling stability (a small overpotential increase of 0.16 V after 120 cycles) and high rate capability (1 A g −1). This work provides an effective electrolyte design principle to realize stable Li deposition and high-performance Li−O 2 batteries. 相似文献
11.
Uneven lithium (Li) electrodeposition hinders the wide application of high-energy-density Li metal batteries (LMBs). Current efforts mainly focus on the side-reaction suppression between Li and electrolyte, neglecting the determinant factor of mass transport in affecting Li deposition. Herein, guided Li + mass transport under the action of a local electric field near magnetic nanoparticles or structures at the Li metal interface, known as the magnetohydrodynamic (MHD) effect, are proposed to promote uniform Li deposition. The modified Li + trajectories are revealed by COMSOL Multiphysics simulations, and verified by the compact and disc-like Li depositions on a model Fe 3O 4 substrate. Furthermore, a patterned mesh with the magnetic Fe−Cr 2O 3 core-shell skeleton is used as a facile and efficient protective structure for Li metal anodes, enabling Li metal batteries to achieve a Coulombic efficiency of 99.5 % over 300 cycles at a high cathode loading of 5.0 mAh cm −2. The Li protection strategy based on the MHD interface design might open a new opportunity to develop high-energy-density LMBs. 相似文献
12.
Without excess Li, anode-free Li-metal batteries (AFLMBs) have been proposed as the most likely solution to realizing highly-safe and cost-effective Li-metal batteries. Nevertheless, short cyclic life puzzles conventional AFLMBs due to anodic dead Li accumulation with a local current concentration induced by irreversible electrolyte depletion, insufficient active Li reservoir and slow Li + transfer at the solid electrolyte interphase (SEI). Herein, SrI 2 is introduced into carbon paper (CP) current collector to effectively suppress dead Li through synergistic mechanisms including reversible I −/I 3− redox reaction to reactivate dead Li, dielectric SEI surface with SrF 2 and LiF to prevent electrolyte decomposition and highly ionic conductive (3.488 mS cm −1) inner layer of SEI with abundant LiI to enable efficient Li + transfer inside. With the SrI 2-modified current collector, the NCM532/CP cell delivers unprecedented cyclic performances with a capacity of 129.2 mAh g −1 after 200 cycles. 相似文献
13.
The electrolytes in lithium metal batteries have to be compatible with both lithium metal anodes and high voltage cathodes, and can be regulated by manipulating the solvation structure. Herein, to enhance the electrolyte stability, lithium nitrate (LiNO 3) and 1,1,2,2-tetrafuoroethyl-2′,2′,2′-trifuoroethyl(HFE) are introduced into the high-concentration sulfolane electrolyte to suppress Li dendrite growth and achieve a high Coulombic efficiency of >99 % for both the Li anode and LiNi 0.8Mn 0.1Co 0.1O 2 (NMC811) cathodes. Molecular dynamics simulations show that NO 3− participates in the solvation sheath of lithium ions enabling more bis(trifluoromethanesulfonyl)imide anion (TFSI −) to coordinate with Li + ions. Therefore, a robust LiN xO y−LiF-rich solid electrolyte interface (SEI) is formed on the Li surface, suppressing Li dendrite growth. The LiNO 3-containing sulfolane electrolyte can also support the highly aggressive LiNi 0.8Mn 0.1Co 0.1O 2 (NMC811) cathode, delivering a discharge capacity of 190.4 mAh g −1 at 0.5 C for 200 cycles with a capacity retention rate of 99.5 %. 相似文献
14.
Solid‐state Li metal batteries (SSLMBs) have attracted considerable interests due to their promising energy density as well as high safety. However, the realization of a well‐matched Li metal/solid‐state electrolyte (SSE) interface remains challenging. Herein, we report g‐C 3N 4 as a new interface enabler. We discover that introducing g‐C 3N 4 into Li metal can not only convert the Li metal/garnet‐type SSE interface from point contact to intimate contact but also greatly enhance the capability to suppress the dendritic Li formation because of the greatly enhanced viscosity, decreased surface tension of molten Li, and the in situ formation of Li 3N at the interface. Thus, the resulting Li‐C 3N 4|SSE|Li‐C 3N 4 symmetric cell gives a significantly low interfacial resistance of 11 Ω cm 2 and a high critical current density (CCD) of 1500 μA cm ?2. In contrast, the same symmetric cell configuration with pristine Li metal electrodes has a much larger interfacial resistance (428 Ω cm 2) and a much lower CCD (50 μA cm ?2). 相似文献
15.
The sluggish sulfur redox kinetics and shuttle effect of lithium polysulfides (LiPSs) are recognized as the main obstacles to the practical applications of the lithium-sulfur (Li−S) batteries. Accelerated conversion by catalysis can mitigate these issues, leading to enhanced Li−S performance. However, a catalyst with single active site cannot simultaneously accelerate multiple LiPSs conversion. Herein, we developed a novel dual-defect (missing linker and missing cluster defects) metal–organic framework (MOF) as a new type of catalyst to achieve synergistic catalysis for the multi-step conversion reaction of LiPSs. Electrochemical tests and first-principle density functional theory (DFT) calculations revealed that different defects can realize targeted acceleration of stepwise reaction kinetics for LiPSs. Specifically, the missing linker defects can selectively accelerate the conversion of S 8→Li 2S 4, while the missing cluster defects can catalyze the reaction of Li 2S 4→Li 2S, so as to effectively inhibit the shuttle effect. Hence, the Li−S battery with an electrolyte to sulfur (E/S) ratio of 8.9 mL g −1 delivers a capacity of 1087 mAh g −1 at 0.2 C after 100 cycles. Even at high sulfur loading of 12.9 mg cm −2 and E/S=3.9 mL g −1, an areal capacity of 10.4 mAh cm −2 for 45 cycles can still be obtained. 相似文献
16.
Li metal is considered an ideal anode material because of its high theoretical capacity and low electrode potential. However, the practical usage of Li metal as an anode is severely limited because of inevitable parasitic side reactions with electrolyte and dendrites formation. At present, single-component artificial solid electrolyte interphase cannot simultaneously meet the multiple functions of promoting ion conduction, guiding lithium ion deposition, inhibiting dendrite growth, and reducing ... 相似文献
17.
The two major issues confronting the commercialization of rechargeable lithium-sulfur (Li−S) batteries are the sluggish kinetics of the sulfur electrochemical reactions on the cathode and inadequate lithium deposition/stripping reversibility on the anode. They are commonly mitigated with additives designed specifically for the anode and the cathode individually. Here, we report the use of a single cathode modifier, In 2Se 3, which can effectively catalyse the polysulfide reactions on the cathode, and also improve the reversibility of Li deposition and removal on the anode through a LiInS 2/LiInSe 2 containing solid electrolyte interface formed in situ by the Se and In ions dissolved in the electrolyte. The amounts of dissolved Se and In are small relative to the amount of In 2Se 3 administered. The benefits of using this single modification approach were verified in Li-metal anode-free Li−S batteries with a Li 2S loading of 4 mg cm −2 and a low electrolyte/Li 2S ratio of 7.5 μL mg −1. The resulting battery showed 60 % capacity retention after 160 cycles at the 0.2 C rate and an average Coulombic efficiency of 98.27 %, comparing very well with recent studies using separate electrode modifiers. 相似文献
18.
Garnet-type electrolytes suffer from unstable chemistry against air exposure, which generates contaminants on electrolyte surface and accounts for poor interfacial contact with the Li metal. Thermal treatment of the garnet at >700 °C could remove the surface contaminants, yet it regenerates the contaminants in the air, and aggravates the Li dendrite issue as more electron-conducting defective sites are exposed. In a departure from the removal approach, here we report a new surface chemistry that converts the contaminants into a fluorinated interface at moderate temperature <180 °C. The modified interface shows a high electron tunneling barrier and a low energy barrier for Li + surface diffusion, so that it enables dendrite-proof Li plating/stripping at a high critical current density of 1.4 mA cm −2. Moreover, the modified interface exhibits high chemical and electrochemical stability against air exposure, which prevents regeneration of contaminants and keeps high critical current density of 1.1 mA cm −2. The new chemistry presents a practical solution for realization of high-energy solid-state Li metal batteries. 相似文献
19.
Li‐O 2 batteries are promising candidates for next‐generation high‐energy‐density battery systems. However, the main problems of Li–O 2 batteries include the poor rate capability of the cathode and the instability of the Li anode. Herein, an ester‐based liquid additive, 2,2,2‐trichloroethyl chloroformate, was introduced into the conventional electrolyte of a Li–O 2 battery. Versatile effects of this additive on the oxygen cathode and the Li metal anode became evident. The Li–O 2 battery showed an outstanding rate capability of 2005 mAh g ?1 with a remarkably decreased charge potential at a large current density of 1000 mA g ?1. The positive effect of the halide ester on the rate capacity is associated with the improved solubility of Li 2O 2 in the electrolyte and the increased diffusion rate of O 2. Furthermore, the ester promotes the formation of a solid–electrolyte interphase layer on the surface of the Li metal, which restrains the loss and volume change of the Li electrode during stripping and plating, thereby achieving a cycling stability over 900 h and a Li capacity utilization of up to 10 mAh cm ?2. 相似文献
20.
It is crucial to obtain a reliable electrolyte system that is used for replacing thermally unstable and the moisture sensitive LiPF 6 salt in liquid electrolytes for developing excellent cycle stability lithium ion batteries with high safety. In this work, a kind of hybrid electrolytes, adding Ga–Bi co-doped Li 7La 3Zr 2O 12 (LLZO) into LiTFSI based commercial electrolyte, was successfully prepared. The results shows that adding Ga–Bi co-doped LLZO ceramic particles is benefit for enhancing conductivity of LiTFSI based commercial electrolyte, which is 3.14 mS cm −1 from 3.02 mS cm −1. Furthermore, the LiFePO 4| |Li cell assembling with LiTFSI based electrolyte with Ga–Bi co-doped LLZO ceramic particles shows good cycle performance and coulomb efficiency (100% except for the initial cycle value of 88%) due to a passivation multi-element film formed for preventing severe corrosion to the Al foil. The battery delivered a high first cycle discharge capacity of 144.2 mAh g −1 (85% of theoretical LiFePO 4.) and a maximum value of 152.6 mAh g −1 after the 69th cycle. After the 300 stable cycle, the capacity of 130.8 mAh g −1 (85.7% of the maximum data) remained. 相似文献
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