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1.
Due to high ionic conductivity and low cost, Li1.4Al0.4Ti1.6(PO4)3 (LATP) has emerged as a promising solid‐state electrolyte for next‐generation lithium (Li) metal solid‐state batterie with high safety performance and energy density. However, the extremely high impedance and surface instability of LATP with Li metal retard its practical application. Herein, a novel method is proposed to construct an ultrathin ZnO layer that is tightly coated on the LATP pellets, surface (ZnO@LATP) via magnetron sputtering, which in situ reacts with Li to form a low electronic conductivity and multifunctional solid electrolyte interphase (SEI). The formed SEI can not only effectively lower the interfacial resistance, but also overcome the side reactions of LATP with the Li metal anode and suppress the Li dendrite growth. Specifically, the interface resistance decreases from 80 554 to 353 Ω and the overpotential reduces from 1 V to 20 mV. As a result, the Li/ZnO@LATP@ZnO/Li symmetric batteries can stably cycle for more than 2000 h without short circuit at 0.05 mA cm?2 and Li/ZnO@LATP/LiFePO4 batteries show excellent cycle stability for 200 cycles at 0.1 C. This work highlights the significance of multifunctional interphase between LATP and Li metal for improvement of interfacial impedance and instability.  相似文献   

2.
Garnet-type Li7La3Zr2O12 (LLZO) solid-state electrolytes have gained significant attention as one of the most promising electrolyte candidates for high-energy-density energy storage devices due to their superior stability and high ionic conductivity. However, the problem of lithium (Li) dendrite penetration into LLZO hinders the practical application of LLZO in solid-state Li metal batteries (SSLMBs). Multidisciplinary evaluations are carried out to understand the mechanism of dendrite penetration. Herein, the formation and evolution of different types of Li dendrites within LLZO are reviewed. The Li dendrite penetration process is addressed from the perspectives of material design, Li/LLZO interfacial adaptability, and the interfacial charge transfer process. On this basis, recent efforts and solutions to inhibiting the penetration of Li dendrites in LLZO, including stabilizing LLZO phase and densification techniques, interfacial modifications, and grain boundary manipulations, are summarized. It is expected that the in-depth understanding of the Li dendrite penetration and corresponding solutions will provide a systemic guideline toward the development of LLZO-based solid-state electrolytes and the commercialization of ultra-stable SSLMBs.  相似文献   

3.
Herein, a composite polymer electrolyte with a viscoelastic and nonflammable interface is designed to handle the contact issue and preclude Li dendrite formation. The composite polymer electrolyte (cellulose acetate/polyethylene glycol/Li1.4Al0.4Ti1.6P3O12) exhibits a wide electrochemical window of 5 V (vs Li+/Li), a high Li+ transference number of 0.61, and an excellent ionic conductivity of above 10?4 S cm?1 at 60 °C. In particular, the intimate contact, low interfacial impedance, and fast ion‐transport process between the electrodes and solid electrolytes can be simultaneously achieved by the viscoelastic and nonflammable layer. Benefiting from this novel design, solid lithium metal batteries with either LiFePO4 or LiCoO2 as cathode exhibit superior cyclability and rate capability, such as a discharge capacity of 157 mA h g?1 after 100 cycles at C/2 and 97 mA h g?1 at 5C for LiFePO4 cathode. Moreover, the smooth and uniform Li surface after long‐term cycling confirms the successful suppression of dendrite formation. The viscoelastic and nonflammable interface modification of solid electrolytes provides a promising and general strategy to handle the interfacial issues and improves the operative safety of solid lithium metal batteries.  相似文献   

4.
High‐performance rechargeable all‐solid‐state lithium metal batteries with high energy density and enhanced safety are attractive for applications like portable electronic devices and electric vehicles. Among the various solid electrolytes, argyrodite Li6PS5Cl with high ionic conductivity and easy processability is of great interest. However, the low interface compatibility between sulfide solid electrolytes and high capacity cathodes like nickel‐rich layered oxides requires many thorny issues to be resolved, such as the space charge layer (SCL) and interfacial reactions. In this work, in situ electrochemical impedance spectroscopy and in situ Raman spectroscopy measurements are performed to monitor the detailed interface evolutions in a LiNi0.8Co0.1Mn0.1O2 (NCM)/Li6PS5Cl/Li cell. Combining with ex situ characterizations including scanning electron microscopy and X‐ray photoelectron spectroscopy, the evolution of the SCL and the chemical bond vibration at NCM/Li6PS5Cl interface during the early cycles is elaborated. It is found that the Li+ ion migration, which varies with the potential change, is a very significant cause of these interface behaviors. For the long‐term cycling, the SCL, interfacial reactions, lithium dendrites, and chemo‐mechanical failure have an integrated effect on interfaces, further deteriorating the interfacial structure and electrochemical performance. This research provides a new insight on intra and intercycle interfacial evolution of solid‐state batteries.  相似文献   

5.
Perovskite‐type solid‐state electrolytes exhibit great potential for the development of all‐solid‐state lithium batteries due to their high Li‐ion conductivity (approaching 10?3 S cm?1), wide potential window, and excellent thermal/chemical stability. However, the large solid–solid interfacial resistance between perovskite electrolytes and electrode materials is still a great challenge that hinders the development of high‐performance all‐solid‐state lithium batteries. In this work, a perovskite‐type Li0.34La0.51TiO3 (LLTO) membrane with vertically aligned microchannels is constructed by a phase‐inversion method. The 3D vertically aligned microchannel framework membrane enables more effective Li‐ion transport between the cathode and solid‐state electrolyte than a planar LLTO membrane. A significant decrease in the perovskite/cathode interfacial resistance, from 853 to 133 Ω cm2, is observed. It is also demonstrated that full cells utilizing LLTO with vertically aligned microchannels as the electrolyte exhibit a high specific capacity and improved rate performance.  相似文献   

6.
There is a growing concern about the cyclability and safety, in particular, of the high‐energy density lithium–metal batteries. This concern is even greater for Li–O2 batteries because O2 that is transported from the cathode to the anode compartment, can exacerbate side reactions and dendrite growth of the lithium metal anode. The key to solving this dilemma lays in tailoring the solid electrolyte interphase (SEI) formed on the lithium metal anode in Li–O2 batteries. Here it is reported that a new electrolyte, formed from LiFSI as the salt and a mixture of tetraethylene glycol dimethyl ether and polymeric ionic liquid of P[C5O2NMA,11]FSI as the solvent, can produce a stable electrode (both cathode and anode)|electrolyte interface in Li–O2 batteries. Specifically, this new electrolyte, when in contact with lithium metal anodes, has the ability to produce a uniform SEI with high ionic conductivity for Li+ transport and desired mechanical property for suppression of dendritic lithium growth. Moreover, the electrolyte possesses a high oxidation tolerance that is very beneficial to the oxygen electrochemistry on the cathode of Li–O2 batteries. As a result, enhanced reversibility and cycle life are realized for the resultant Li–O2 batteries.  相似文献   

7.
Replacing organic liquid electrolyte with inorganic solid electrolytes (SE) can potentially address the inherent safety problems in conventional rechargeable batteries. However, solid‐state batteries (SSBs) have been plagued by the relatively low ionic conductivity of SEs and large charge‐transfer resistance between electrode and SE. Here, a new design strategy is reported for improving the ionic conductivity of SE by self‐forming a composite material. An optimized Na+ ion conducting composite electrolyte derived from the Na1+ n Zr2Si n P3? n O12 NASICON (Na Super Ionic Conductor) structure is successfully synthesized, yielding ultrahigh ionic conductivity of 3.4 mS cm?1 at 25 °C and 14 mS cm?1 at 80 °C. On the other hand, in order to enhance the charge‐transfer rate at the electrode/electrolyte interface, an interface modification strategy is demonstrated by utilization of a small amount of nonflammable and nonvolatile ionic liquid (IL) at the cathode side in SSBs. The IL acts as a wetting agent, enabling a favorable interface kinetic in SSBs. The Na3V2(PO4)3/IL/SE/Na SSB exhibits excellent cycle performance and rate capability. A specific capacity of ≈90 mA h g?1 is maintained after 10 000 cycles without capacity decay under 10 C rate at room temperature. This provides a new perspective to design fast ion conductors and fabricate long life SSBs.  相似文献   

8.
The development of high‐voltage LiCoO2 is essential for achieving lithium‐ion batteries with high volumetric energy density, however, it faces a great deal of challenges owing to the materials, structure and interfacial instability issues. In this work, a strategy is developed, through heat annealing a precoated surface layer to in situ form a high‐voltage‐stable surface coating layer, which is demonstrated to be highly effective to improve the high‐voltage performance of LiCoO2. It is discovered that LiCoO2 reacts with Li1.5Al0.5Ti1.5(PO4)3 (LATP) at 700 °C to form exclusively spinel phases in addition to Li3PO4, which are structurally coherent to the layered lattice of LiCoO2. The heat annealing of the precoated thin layer of LATP enables the formation of a high‐quality surface layer. Spinel phases possess high‐voltage‐stable structures with much weaker oxidizing ability of lattice oxygen than layered structure. In addition, the Li3PO4 is a good lithium‐ion conductor with excellent chemical stability at high voltages. All these benefits contribute to the construction of a uniform and conformal high‐voltage‐stable surface layer with favorable lithium conducting kinetics at the LiCoO2 surface. The modified LiCoO2 shows excellent 4.6 V high‐voltage cycle performance at both room temperature and 45 °C. The thermal stability is greatly enhanced as well.  相似文献   

9.
Various electrolyte additives are developed to construct a cathode electrolyte interphase (CEI) layer for high-voltage LiCoO2 since the cathode suffers severe interfacial degradation when increasing the cut-off voltage over 4.55 V. However, the CEI derived from the additive sacrificial reaction faces the risk of rupture due to the corrosion reaction and the volumetric variation of the cathode. Herein, a non-passivating cathode interface is realized for 4.6 V LiCoO2 with a non-sacrificial electrolyte additive (TBAClO4) by regulating the solvent environment at the interface rather than the preferential decomposition for CEI formation. Owing to the novel protection mechanism, the cell performance shows little dependence on the CEI-formation process. Therefore, an ultra-high initial coulombic efficiency (96.63%) and excellent cycling stability (81% capacity retention after 300 cycles) are achieved in Li||LiCoO2 batteries. Moreover, even with the electrolyte containing 1000 ppm H2O, the remarkable water capture ability of the additive together with its interfacial regulation enables the 4.6 V Li||LiCoO2 battery to retain 80% capacity after 200 cycles. This non-sacrificial strategy provides new insights into high-voltage electrolyte additive design for high-energy-density lithium metal batteries.  相似文献   

10.
Owing to its high theoretical specific capacity (1166 mA h g?1) and particularly its advantage to be paired with a lithium‐metal‐free anode, lithium sulfide (Li2S) is regarded as a much safer cathode for next‐generation advanced lithium–sulfur (Li–S) batteries. However, the low conductivity of Li2S and particularly the severe “polysulfide shuttle” of lithium polysulfide (LiPS) dramatically hinder their practical application in Li–S batteries. To address such issues, herein a bifuctional 3D metal sulfide‐decorated carbon sponge (3DTSC), which is constructed by 1D carbon nanowires cross‐linked with 2D graphene nanosheets with high conductivity and polar 0D metal sulfide nanodots with efficient electrocatalytic activity and strong chemical adsorption capability for LiPSs, is presented. Benefiting from the well‐designed multiscale, multidimensional 3D porous nanoarchitecture with high conductivity, and efficient electrocatalytic and absorption ability, the 3DTSC significantly mitigates LiPS shuttle, improves the utilization of Li2S, and facilitates the transport of electrons and ions. As a result, even with a high Li2S loading of 8 mg cm?2, the freestanding 3DTSC‐Li2S cathode without a polymer binder and metallic current collector delivers outstanding electrochemical performance with a high areal capacity of 8.44 mA h cm?2.  相似文献   

11.
After the research that shows that Li10GeP2S12 (LGPS)‐type sulfide solid electrolytes can reach the high ionic conductivity at the room temperature, sulfide solid electrolytes have been intensively developed with regard to ionic conductivity and mechanical properties. As a result, an increasing volume of research has been conducted to employ all‐solid‐state lithium batteries in electric automobiles within the next five years. To achieve this goal, it is important to review the research over the past decade, and understand the requirements for future research necessary to realize the practical applications of all‐solid‐state lithium batteries. To date, research on all‐solid‐state lithium batteries has focused on achieving overpotential properties similar to those of conventional liquid‐lithium‐ion batteries by increasing the ionic conductivity of the solid electrolytes. However, the increase in the ionic conductivity should be accompanied by improvements of the electronic conductivity within the electrode to enable practical applications. This essay provides a critical overview of the recent progress and future research directions of the all‐solid‐state lithium batteries for practical applications.  相似文献   

12.
Interfacial reactions between ceramic‐sulfide solid‐electrolytes and common electrodes have remained a major impediment to the development of solid‐state lithium‐ion batteries. In practice, this means that ceramic‐sulfide batteries require a suitable coating material to isolate the electrolyte from the electrode materials. In this work, the interfacial stability of Li10SiP2S12 with over 67 000 materials is computationally evaluated. Over 2000 materials that are predicted to form stable interfaces in the cathode voltage range and over 1000 materials for the anode range are reported on and cataloged. LiCoO2 is chosen as an example cathode material to identify coating compounds that are stable with both Li10SiP2S12 and a common cathode. The correlation between elemental composition and multiple instability metrics (e.g., chemical/electrochemical) is analyzed, revealing key trends in, amongst others, the role of anion selection. A new binary‐search algorithm is introduced for evaluating the pseudo‐phase with improved speed and accuracy. Computational challenges posed by high‐throughput interfacial phase‐diagram calculations are highlighted as well as pragmatic computational methods to make such calculations routinely feasible. In addition to the over 3000 materials cataloged, representative materials from the anionic classes of oxides, fluorides, and sulfides are chosen to experimentally demonstrate chemical stability when in contact with Li10SiP2S12.  相似文献   

13.
A smooth interfacial contact between electrode and electrolyte, alleviation of dendrite formation, low internal resistance, and preparation of thin electrolyte (<20 µm) are the key challenging tasks in the practical application of Li7La3Zr2O12 (LLZO)-based solid-state batteries (SSBs). This paper develops a unique strategy to reduce interfacial resistance by designing an interface-based core–shell structure via direct integration of Al-LLZO ceramic nanofibers incorporated poly(vinylidene fluoride)/LiTFSI on the surface of a porous cathode electrode (HPEIC). This yields an ultrathin solid polymer electrolyte with a thickness of 7 µm. The integrated HPEIC/Li SSB with LiFePO4/C exhibits an initial specific capacity of 166 mAh g−1 at 0.1 C and 159 mAh g−1 with capacity retention of 100% after 120 cycles at 0.5 C (25 °C). The HPEIC/Li SSB with LiNi0.8Mn0.1Co0.1O2 cathode delivers a good discharge capacity of 134 mAh g−1 after 120 cycles at 0.5 C. The rational design of interface-based core–shell structure outperforms the conventional assembly of solid-state cells using free-standing solid electrolytes in specific capacity, internal resistance, and rate performance. The proposed strategy is simple, cost-effective, robust, and scalable manufacturing, which is essential for the practical applicability of SSBs.  相似文献   

14.
High ionic conductivity of up to 6.4 × 10?3 S cm?1 near room temperature (40 °C) in lithium amide‐borohydrides is reported, comparable to values of liquid organic electrolytes commonly employed in lithium‐ion batteries. Density functional theory is applied coupled with X‐ray diffraction, calorimetry, and nuclear magnetic resonance experiments to shed light on the conduction mechanism. A Li4Ti5O12 half‐cell battery incorporating the lithium amide‐borohydride electrolyte exhibits good rate performance up to 3.5 mA cm?2 (5 C) and stable cycling over 400 cycles at 1 C at 40 °C, indicating high bulk and interfacial stability. The results demonstrate the potential of lithium amide‐borohydrides as solid‐state electrolytes for high‐power lithium‐ion batteries.  相似文献   

15.
Li‐rich layered oxides (LLOs) can deliver almost double the capacity of conventional electrode materials such as LiCoO2 and LiMn2O4; however, voltage fade and capacity degradation are major obstacles to the practical implementation of LLOs in high‐energy lithium‐ion batteries. Herein, hexagonal La0.8Sr0.2MnO3?y (LSM) is used as a protective and phase‐compatible surface layer to stabilize the Li‐rich layered Li1.2Ni0.13Co0.13Mn0.54O2 (LM) cathode material. The LSM is Mn? O? M bonded at the LSM/LM interface and functions by preventing the migration of metal ions in the LM associated with capacity degradation as well as enhancing the electrical transfer and ionic conductivity at the interface. The LSM‐coated LM delivers an enhanced reversible capacity of 202 mAh g?1 at 1 C (260 mA g?1) with excellent cycling stability and rate capability (94% capacity retention after 200 cycles and 144 mAh g?1 at 5 C). This work demonstrates that interfacial bonding between coating and bulk material is a successful strategy for the modification of LLO electrodes for the next‐generation of high‐energy Li‐ion batteries.  相似文献   

16.
The development of all‐solid‐state lithium–sulfur batteries is hindered by the poor interfacial properties at solid electrolyte (SE)/electrode interfaces. The interface is modified by employing the highly concentrated solvate electrolyte, (MeCN)2?LiTFSI:TTE, as an interlayer material at the electrolyte/electrode interfaces. The incorporation of an interlayer significantly improves the cycling performance of solid‐state Li2S batteries compared to the bare counterpart, exhibiting a specific capacity of 760 mAh g?1 at cycle 100 (330 mAh g?1 for the bare cell). Electrochemical impedance spectroscopy shows that the interfacial resistance of the interlayer‐modified cell gradually decreases as a function of cycle number, while the impedance of the bare cell remains almost constant. Cross‐section scanning electron microscopy (SEM)/ energy dispersive X‐ray spectroscopy (EDS) measurements on the interlayer‐modified cell confirm the permeation of solvate into the cathode and the SE with electrochemical cycling, which is related to the decrease in cell impedance. In order to mimic the full permeation of the solvate across the entire cell, the solvate is directly mixed with the SE to form a “solvSEM” electrolyte. The hybrid Li2S cell using a solvSEM electrolyte exhibits superior cycling performance compared to the solid‐state cells, in terms of Li2S loading, Li2S utilization, and cycling stability. The improved performance is due to the favorable ionic contact at the battery interfaces.  相似文献   

17.
The garnet-type phase Li7La3Zr2O12 (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs.  相似文献   

18.
Thin solid‐state electrolytes with nonflammability, high ionic conductivity, low interfacial resistance, and good processability are urgently required for next‐generation safe, high energy density lithium metal batteries. Here, a 3D Li6.75La3Zr1.75Ta0.25O12 (LLZTO) self‐supporting framework interconnected by polytetrafluoroethylene (PTFE) binder is prepared through a simple grinding method without any solvent. Subsequently, a garnet‐based composite electrolyte is achieved through filling the flexible 3D LLZTO framework with a succinonitrile solid electrolyte. Due to the high content of garnet ceramic (80.4 wt%) and high heat‐resistance of the PTFE binder, such a composite electrolyte film with nonflammability and high processability exhibits a wide electrochemical window of 4.8 V versus Li/Li+ and high ionic transference number of 0.53. The continuous Li+ transfer channels between interconnected LLZTO particles and succinonitrile, and the soft electrolyte/electrode interface jointly contribute to a high ambient‐temperature ionic conductivity of 1.2 × 10?4 S cm?1 and excellent long‐term stability of the Li symmetric battery (stable at a current density of 0.1 mA cm?2 for over 500 h). Furthermore, as‐prepared LiFePO4|Li and LiNi0.5Mn0.3Co0.2O2|Li batteries based on the thin composite electrolyte exhibit high discharge specific capacities of 153 and 158 mAh g?1 respectively, and desirable cyclic stabilities at room temperature.  相似文献   

19.
The lithium–sulfur (Li–S) battery is considered a promising candidate for the next generation of energy storage system due to its high specific energy density and low cost of raw materials. However, the practical application of Li–S batteries is severely limited by several weaknesses such as the shuttle effect of polysulfides and the insulation of the electrochemical products of sulfur and Li2S/Li2S2. Here, by doping nitrogen and integrating highly dispersed cobalt catalysts, a porous carbon nanocage derived from glucose adsorbed metal–organic framework is developed as the host for a sulfur cathode. This host structure combines the reported positive effects, including high conductivity, high sulfur loading, effective stress release, fast lithium‐ion kinetics, fast interface charge transport, fast redox of Li2Sn, and strong physical/chemical absorption, achieving a long cycle life (86% of capacity retention at 1C within 500 cycles) and high rate performance (600 mAh g?1 at 5C) for a Li–S battery. By combining experiments and density functional theoretical calculations, it is demonstrated that the well‐dispersed cobalt clusters play an important role in greatly improving the diffusion dynamics of lithium, and enhance the absorption and conversion capability of polysulfides in the host structure.  相似文献   

20.
Lithium‐sulfur (Li‐S) batteries are being considered as the next‐generation high‐energy‐storage system due to their high theoretical energy density. However, the use of a lithium‐metal anode poses serious safety concerns due to lithium dendrite formation, which causes short‐circuiting, and possible explosions of the cell. One feasible way to address this issue is to pair a fully lithiated lithium sulfide (Li2S) cathode with lithium metal‐free anodes. However, bulk Li2S particles face the challenges of having a large activation barrier during the initial charge, low active‐material utilization, poor electrical conductivity, and fast capacity fade, preventing their practical utility. Here, the development of a self‐supported, high capacity, long‐life cathode material is presented for Li‐S batteries by coating Li2S onto doped graphene aerogels via a simple liquid infiltration–evaporation coating method. The resultant cathodes are able to lower the initial charge voltage barrier and attain a high specific capacity, good rate capability, and excellent cycling stability. The improved performance can be attributed to the (i) cross‐linked, porous graphene network enabling fast electron/ion transfer, (ii) coated Li2S on graphene with high utilization and a reduced energy barrier, and (iii) doped heteroatoms with a strong binding affinity toward Li2S/lithium polysulfides with reduced polysulfide dissolution based on first‐principles calculations.  相似文献   

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