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1.
Rechargeable batteries with a Li metal anode and Ni‐rich Li[NixCoyMn1?x?y]O2 cathode (Li/Ni‐rich NCM battery) have been emerging as promising energy storage devices because of their high‐energy density. However, Li/Ni‐rich NCM batteries have been plagued by the issue of the thermodynamic instability of the Li metal anode and aggressive surface chemistry of the Ni‐rich cathode against electrolyte solution. In this study, a bi‐functional additive, adiponitrile (C6H8N2), is proposed which can effectively stabilize both the Li metal anode and Ni‐rich NCM cathode interfaces. In the Li/Ni‐rich NCM battery, the addition of 1 wt% adiponitrile in 0.8 m LiTFSI + 0.2 M LiDFOB + 0.05 M LiPF6 dissolved in EMC/FEC = 3:1 electrolyte helps to produce a conductive and robust Li anode/electrolyte interface, while strong coordination between Ni4+ on the delithiated Ni‐rich cathode and nitrile group in adiponitrile reduces parasitic reactions between the electrolyte and Ni‐rich cathode surface. Therefore, upon using 1 wt% adiponitrile, the Li/full concentration gradient Li[Ni0.73Co0.10Mn0.15Al0.02]O2 battery achieves an unprecedented cycle retention of 75% over 830 cycles under high‐capacity loading of 1.8 mAh cm?2 and fast charge–discharge time of 2 h. This work marks an important step in the development of high‐performance Li/Ni‐rich NCM batteries with efficient electrolyte additives.  相似文献   

2.
The manganese dissolution leading to sharp capacity decline as well as the sluggish reaction kinetic are still major issues for manganese‐based materials as aqueous zinc‐ion batteries (ZIBs) cathodes. Here, a potassium‐ion‐stabilized and oxygen‐defect K0.8Mn8O16 is reported as a high‐energy‐density and durable cathode for neutral aqueous ZIBs. A new insight into suppressing manganese dissolution via incorporation of K+ ions to intrinsically stabilize the Mn‐based cathodes is provided. A comprehensive study suggests that oxygen defects improve electrical conductivity and open the MnO6 polyhedron walls for ion diffusion, which plays a critical role in the fast reaction kinetics and capacity improvement of K0.8Mn8O16. In addition, direct evidence for the mechanistic details of simultaneous insertion and conversion reaction based on H+‐storage mechanism is demonstrated. As expected, a significant energy output of 398 W h kg?1 (based on the mass of cathode) and an impressive durability over 1000 cycles with no obvious capacity fading are obtained. Such a high‐energy Zn‐K0.8Mn8O16 battery, as well as the basic understanding of manganese dissolution and oxygen defects may open new opportunities toward high‐performance aqueous ZIBs.  相似文献   

3.
Mg batteries as the most typical multivalent batteries are attracting increasing attention because of resource abundance, high volumetric energy density, and smooth plating/stripping of Mg anodes. However, current limitations for the progress of Mg batteries come from the lack of high voltage electrolytes and fast Mg‐insertable structure prototypes. In order to improve their energy or power density, hybrid systems combining Li‐driven cathode reaction with Mg anode process appear to be a potential solution by bypassing the aforementioned limitations. Here, FeS x (x = 1 or 2) is employed as conversion cathode with 2–4 electron transfers to achieve a maximum energy density close to 400 Wh kg?1, which is comparable with that of Li‐ion batteries but without serious dendrite growth and polysulphide dissolution. In situ formation of solid electrolyte interfaces on both sulfide and Mg electrodes is likely responsible for long‐life cycling and suppression of S‐species passivation at Mg anodes. Without any decoration on the cathode, electrolyte additive, or anode protection, a reversible capacity of more than 200 mAh g?1 is still preserved for Mg/FeS2 after 200 cycles.  相似文献   

4.
The realization of manganese oxide anode materials for lithium‐ion batteries is hindered by inferior cycle stability, rate capability, and high overpotential induced by the agglomeration of manganese metal grains, low conductivity of manganese oxide, and the high stress/strain in the crystalline manganese oxide structure during the repeated lithiation/delithiation process. To overcome these challenges, unique amorphous MnOx–C nanocomposite particles with interdispersed carbon are synthesized using aerosol spray pyrolysis. The carbon filled in the pores of amorphous MnOx blocks the penetration of liquid electrolyte to the inside of MnOx, thus reducing the formation of a solid electrolyte interphase and lowering the irreversible capacity. The high electronic and lithium‐ion conductivity of carbon also enhances the rate capability. Moreover, the interdispersed carbon functions as a barrier structure to prevent manganese grain agglomeration. The amorphous structure of MnOx brings additional benefits by reducing the stress/strain of the conversion reaction, thus lowering lithiation/delithiation overpotential. As the result, the amorphous MnOx‐C particles demonstrated the best performance as an anode material for lithium‐ion batteries to date.  相似文献   

5.
An increase in the energy density of lithium‐ion batteries has long been a competitive advantage for advanced wireless devices and long‐driving electric vehicles. Li‐rich layered oxide, xLi2MnO3?(1?x)LiMn1?y?zNiyCozO2, is a promising high‐capacity cathode material for high‐energy batteries, whose capacity increases by increasing charge voltage to above 4.6 V versus Li. Li‐rich layered oxide cathode however suffers from a rapid capacity fade during the high‐voltage cycling because of instable cathode–electrolyte interface, and the occurrence of metal dissolution, particle cracking, and structural degradation, particularly, at elevated temperatures. Herein, this study reports the development of fluorinated polyimide as a novel high‐voltage binder, which mitigates the cathode degradation problems through superior binding ability to conventional polyvinylidenefluoride binder and the formation of robust surface structure at the cathode. A full‐cell consisting of fluorinated polyimide binder‐assisted Li‐rich layered oxide cathode and conventional electrolyte without any electrolyte additive exhibits significantly improved capacity retention to 89% at the 100th cycle and discharge capacity to 223–198 mA h g?1 even under the harsh condition of 55 °C and high charge voltage of 4.7 V, in contrast to a rapid performance fade of the cathode coated with polyvinylidenefluoride binder.  相似文献   

6.
Rechargeable aqueous Zn‐based batteries, benefiting from their good reliability, low cost, high energy/power densities, and ecofriendliness, show great potential in energy storage systems. However, the poor cycling performance due to the formation of Zn dendrites greatly hinders their practical applications. In this work, a trilayer 3D CC‐ZnO@C‐Zn anode is obtained by in situ growing ZIFs (zeolitic‐imidazolate frameworks) derived ZnO@C core–shell nanorods on carbon cloth followed by Zn deposition, which exhibits excellent antidendrite performance. Using CC‐ZnO@C‐Zn as the anode and a branch‐like Co(CO3)0.5(OH)x·0.11H2O@CoMoO4 (CC‐CCH@CMO) as the cathode, a Zn–Co battery is rationally designed, displaying excellent energy/power densities (235 Wh kg?1, 12.6 kW kg?1) and remarkable cycling performance (71.1% after 5000 cycles). Impressively, when using a gel electrolyte, a highly customizable, fiber‐shaped flexible all‐solid‐state Zn–Co battery is assembled for the first time, which presents a high energy density of 4.6 mWh cm?3, peak power density of 0.42 W cm?3, and long durability (82% capacity retention after 1600 cycles) as well as excellent flexibility. The unique 3D electrode design in this study provides a novel approach to achieve high‐performance Zn‐based batteries, showing promising applications in flexible and portable energy‐storage systems.  相似文献   

7.
Sodium manganese hexacyanoferrate (NaxMnFe(CN)6) is one of the most promising cathode materials for sodium‐ion batteries (SIBs) due to the high voltage and low cost. However, its cycling performance is limited by the multiple phase transitions during Na+ insertion/extraction. In this work, a facile strategy is developed to synthesize cubic and monoclinic structured NaxMnFe(CN)6, and their structure evolutions are investigated through in situ X‐ray diffraction (XRD), ex situ Raman, and X‐ray photoelectron spectroscopy (XPS) characterizations. It is revealed that the monoclinic phase undergoes undesirable multiple two‐phase reactions (monoclinic ? cubic ? tetragonal) due to the large lattice distortions caused by the Jahn–Teller effects of Mn3+, resulting in poor cycling performances with 38% capacity retention. The cubic NaxMnFe(CN)6 with high structural symmetry maintains the structural stability during the repeated Na+ insertion/extraction process, demonstrating impressive electrochemical performances with specific capacity of ≈120 mAh g?1 at 3.5 V (vs Na/Na+), capacity retention of ≈70% over 500 cycles at 200 mA g?1. In addition, the TiO2//C‐MnHCF full battery is fabricated with an energy density of 111 Wh kg?1, suggesting the great potential of cubic NaxMnFe(CN)6 for practical energy storage applications.  相似文献   

8.
Rechargeable Zn-MnO2 batteries are boosted by the reversible intercalation reactions in mild aqueous electrolytes, but they still suffer from cathode degradation. Herein, Zn-MnO2 batteries with high durability and high energy density are achieved by supplementing MnO2 deposition and dissolution in a mild aqueous electrolyte. The main finding is that adjusting Mn2+ concentration to a critical range enables a reversible MnO2/Mn2+ redox conversion without the involvement of oxygen evolution. This can recycle the by-products from MnOOH disproportionation (MnOOH → MnO2 + Mn2+), resulting in a battery with extremely high durability (16 000 cycles without obvious capacity fading), high energy density (602 Wh kg−1 based on the active mass of the cathode), and high-rate capacity (430 mAh g−1 at 19.5 A g−1). The utilization of a 3D carbon nanotube foam skeleton can accommodate the volume change during MnO2 deposition/dissolution and provide paths for efficient charge and mass transport. This work provides a feasible way to push the development of Zn-MnO2 batteries in mild aqueous electrolytes.  相似文献   

9.
Potassium‐ion batteries have been regarded as the potential alternatives to lithium‐ion batteries (LIBs) due to the low cost, earth abundance, and low potential of K (?2.936 vs standard hydrogen electrode (SHE)). However, the lack of low‐cost cathodes with high energy density and long cycle life always limits its application. In this work, high‐energy layered P2‐type hierarchical K0.65Fe0.5Mn0.5O2 (P2‐KFMO) microspheres, assembled by the primary nanoparticles, are fabricated via a modified solvent‐thermal method. Benefiting from the unique microspheres with primary nanoparticles, the K+ intercalation/deintercalation kinetics of P2‐KFMO is greatly enhanced with a stabilized cathodic electrolyte interphase on the cathode. The P2‐KFMO microsphere presents a highly reversible potassium storage capacity of 151 mAh g?1 at 20 mA g?1, fast rate capability of 103 mAh g?1 at 100 mA g?1, and long cycling stability with 78% capacity retention after 350 cycles. A full cell with P2‐KFMO microspheres as cathode and hard carbon as anode is constructed, which exhibits long‐term cycling stability (>80% of retention after 100 cycles). The present high‐performance P2‐KFMO microsphere cathode synthesized using earth‐abundant elements provides a new cost‐effective alternative to LIBs for large‐scale energy storage.  相似文献   

10.
Rechargeable aqueous zinc‐ion batteries hold great promise for potential applications in large‐scale energy storage, but the reversible insertion of bivalent Zn2+ and fast reaction kinetics remain elusive goals. Hence, a highly reversible Zn/VNx Oy battery is developed, which combines the insertion/extraction reaction and pseudo‐capacitance‐liked surface redox reaction mechanism. The energy storage is induced by a simultaneous reversible cationic (V3+ ? V2+) and anionic (N3? ? N2?) redox reaction, which are mainly responsible for the high reversibility and no structural degradation of VNxOy. As expected, a superior rate capability of 200 mA h g?1 at 30 A g?1 and high cycling stability up to 2000 cycles are achieved. This finding opens new opportunities for the design of high‐performance cathodes with fast Zn2+ reaction kinetics for advanced aqueous zinc‐ion batteries.  相似文献   

11.
Silicon (Si) and lithium metal are the most favorable anodes for high‐energy‐density lithium‐based batteries. However, large volume expansion and low electrical conductivity restrict commercialization of Si anodes, while dendrite formation prohibits the applications of lithium‐metal anodes. Here, uniform nanoporous Si@carbon (NPSi@C) from commercial alloy and CO2 is fabricated and tested as a stable anode for lithium‐ion batteries (LIBs). The porosity of Si as well as graphitization degree and thickness of the carbon layer can be controlled by adjusting reaction conditions. The rationally designed porosity and carbon layer of NPSi@C can improve electronic conductivity and buffer volume change of Si without destroying the carbon layer or disrupting the solid electrolyte interface layer. The optimized NPSi@C anode shows a stable cyclability with 0.00685% capacity decay per cycle at 5 A g?1 over 2000 cycles for LIBs. The energy storage mechanism is explored by quantitative kinetics analysis and proven to be a capacitance‐battery dual model. Moreover, a novel 2D/3D structure is designed by combining MXene and NPSi@C. As lithiophilic nucleation seeds, NPSi@C can induce uniform Li deposition with buffered volume expansion, which is proven by exploring Li‐metal deposition morphology on Cu foil and MXene@NPSi@C. The practical potential application of NPSi@C and MXene@NPSi@C is evaluated by full cell tests with a Li(Ni0.8Co0.1Mn0.1)O2 cathode.  相似文献   

12.
Potassium‐ion batteries (KIBs) are emerging as one of the most promising candidates for large‐scale energy storage owing to the natural abundance of the materials required for their fabrication and the fact that their intercalation mechanism is identical to that of lithium‐ion batteries. However, the larger ionic radius of K+ is likely to induce larger volume expansion and sluggish kinetics, resulting in low specific capacity and unsatisfactory cycle stability. A new Ni/Mn‐based layered oxide, P2‐type K0.44Ni0.22Mn0.78O2, is designed and synthesized. A cathode designed using this material delivers a high specific capacity of 125.5 mAh g?1 at 10 mA g?1, good cycle stability with capacity retention of 67% over 500 cycles and fast kinetic properties. In situ X‐ray diffraction recorded for the initial two cycles reveals single solid‐solution processes under P2‐type framework with small volume change of 1.5%. Moreover, a cathode electrolyte interphase layer is observed on the surface of the electrode after cycling with possible components of K2CO3, RCO2K, KOR, KF, etc. A full cell using K0.44Ni0.22Mn0.78O2 as the cathode and soft carbon as the anode also exhibits exceptional performance, with capacity retention of 90% over 500 cycles as well as superior rate performance. These findings suggest P2‐K0.44Ni0.22Mn0.78O2 is a promising candidate as a high‐performance cathode for KIBs.  相似文献   

13.
Zn batteries potentially offer the highest energy density among aqueous batteries that are inherently safe, inexpensive, and sustainable. However, most cathode materials in Zn batteries suffer from capacity fading, particularly at a low current rate. Herein, it is shown that the ZnCl2 “water‐in‐salt” electrolyte (WiSE) addresses this capacity fading problem to a large extent by facilitating unprecedented performance of a Zn battery cathode of Ca0.20V2O5?0.80H2O. Upon increasing the concentration of aqueous ZnCl2 electrolytes from 1 m to 30 m, the capacity of Ca0.20V2O5?0.80H2O rises from 296 mAh g?1 to 496 mAh g?1; its absolute working potential increases by 0.4 V, and most importantly, at a low current rate of 50 mA g?1, that is, C/10; its capacity retention increases from 8.4% to 51.1% over 100 cycles. Ex situ characterization results point to the formation of a new ready‐to‐dissolve phase on the electrode in the dilute electrolyte. The results demonstrate that the Zn‐based WiSE may provide the underpinning platform for the applications of Zn batteries for stationary grid‐level storage.  相似文献   

14.
Aqueous dual‐ion batteries (DIBs) are promising for large‐scale energy storage due to low cost and inherent safety. However, DIBs are limited by low capacity and poor cycling of cathode materials and the challenge of electrolyte decomposition. In this study, a new cathode material of nitrogen‐doped microcrystalline graphene‐like carbon is investigated in a water‐in‐salt electrolyte of 30 m ZnCl2, where this carbon cathode stores anions reversibly via both electrical double layer adsorption and ion insertion. The (de)insertion of anions in carbon lattice delivers a high‐potential plateau at 1.85 V versus Zn2+/Zn, contributing nearly 1/3 of the capacity of 134 mAh g?1 and half of the stored energy. This study shows that both the unique carbon structure and concentrated ZnCl2 electrolyte play critical roles in allowing anion storage in carbon cathode for this aqueous DIB.  相似文献   

15.
Lithium–carbon dioxide (Li–CO2) batteries have received wide attention due to their high theoretical energy density and CO2 capture capability. However, this system still faces poor cycling performance and huge overpotential, which stems from the leakage/volatilization of liquid electrolyte and instability of the cathode. A gel polymer electrolyte (GPE)‐based Li–CO2 battery by using a novel pencil‐trace cathode and 0.0025 mol L?1 (M) binuclear cobalt phthalocyanine (Bi‐CoPc)‐containing GPE (Bi‐CoPc‐GPE) is developed here. The cathode, which is prepared by pencil drawing on carbon paper, is stable because of its typical limited‐layered graphitic structure without any binder. In addition, Bi‐CoPc‐GPE, which consists of polymer matrix filled with liquid electrolyte, exhibits excellent ion conductivity (0.86 mS cm?1), effective protection for Li anode, and superior leakproof property. Moreover, Bi‐CoPc acts as a redox mediator to promote the decomposition of discharge products at low charge potential. Interestingly, different from polymer‐shaped discharge products formed in liquid electrolyte–based Li–CO2 batteries, the morphology of products in Li–CO2 batteries using Bi‐CoPc‐GPE is film‐like. Hence, this polymer‐based Li–CO2 battery shows super‐high discharge capacity, low overpotential, and even steadily runs for 120 cycles. This study may pave a new way to develop high‐performance Li–CO2 batteries.  相似文献   

16.
Highly efficient non‐noble metal electrocatalysts are vital for metal–air batteries and fuel cells. Herein, a noble‐metal–free single‐atom Fe‐N x‐C electrocatalyst is synthesized by incorporating Fe‐Phen complexes into the nanocages in situ during the growth of ZIF‐8, followed by pyrolysis at 900 °C under inert atmosphere. Fe‐Phen species provide both Fe2+ and the organic ligand (Phen) simultaneously, which play significant roles in preparing single‐atom catalysts. The obtained Fe‐Nx‐C exhibits a half‐wave potential of 0.91 V for the oxygen reduction reaction, higher than that of commercial Pt/C (0.82 V). As a cathode catalyst for primary zinc–air batteries (ZABs), the battery shows excellent electrochemical performances in terms of the high open‐circuit voltage (OCV) of 1.51 V and a high power density of 96.4 mW cm?2. The rechargeable ZAB with Fe‐Nx‐C catalyst and the alkaline electrolyte shows a remarkable cycling performance for 300 h with an initial round‐trip efficiency of 59.6%. Furthermore, the rechargeable all‐solid‐state ZABs with the Fe‐Nx‐C catalyst show high OCV of 1.49 V, long cycle life for 120 h, and foldability. The single‐atom Fe‐Nx‐C electrocatalyst may function as a promising catalyst for various metal–air batteries and fuel cells.  相似文献   

17.
Exfoliating graphite to graphene has attracted great attention due to the fantastic properties of graphene available for designing graphene‐based materials or devices. Besides the classic solution method, herein a unique role of TiO2 in exfoliating graphite to be graphene layers effectively is reported. As a paradigm, this discovered effect of TiO2 is significant for preparing high‐performance graphene‐modified SiOx‐based anode in lithium‐ion batteries (LIBs), in which the graphite is in situ exfoliated mechanically by TiO2 to be multilayered graphene (i.e., MLG) and then the SiOx is wrapped by the MLG to construct a SiOx/TiO2@MLG. In this case, an extremely high capacity of 1484 mAh g?1, long lifespan over 1200 cycles at 2 A g?1, as well as good performance in full LIBs (vs nickel‐rich cathode) are demonstrated. It is confirmed that the MLG can enhance electric conductivity, mitigate electrolyte decomposition, and alleviate volume effect of the SiOx effectively. This result is hard to be achieved using other kinds of metal oxide besides TiO2. It is hoped that the SiOx/TiO2@MLG is practical for pursuing LIBs with an energy density beyond 300 Wh kg?1. In addition, it is believed the ingenious strategy is applicable for designing more functional materials with greater capabilities.  相似文献   

18.
Intrinsically stable materials are desirable for constructing energy storage devices, which aim to demonstrate durability under the harsh electrochemical conditions that are detrimental to their lifespan. However, it is demonstrated here that the intrinsic instability of an electrochemical interface can be converted from an obstacle into an advantage. In aqueous zinc-ion batteries, manganese oxide (MnO2) exhibits considerable dissolution even in electrolyte containing Mn2+ salt. Balancing with redeposition alleviates the harmful impact of dissolution on performance and alters the trajectory of the active phase. Inclusion of Mn2+ salt in the electrolyte induces MnO2 deposition on all conductive surfaces, requiring that distracting side reactions be eliminated to isolate the dynamics of the active phase. Under conditions favoring dissolution, capacity decreases dramatically and a highly crystalline tetragonal ZnMn2O4 phase forms, while redeposition helps maintain capacity and promotes a disordered cubic Zn-rich phase. Ultimately, this work aims to illuminate a path forward to unlock the potential of batteries made with materials that are fundamentally unstable in their operating environment.  相似文献   

19.
Currently, development of suitable cathode materials for zinc‐ion batteries (ZIBs) is plagued by the sluggish kinetics of Zn2+ with multivalent charge in the host structure. Herein, it is demonstrated that interlayer Mn2+‐doped layered vanadium oxide (Mn0.15V2O5·nH2O) composites with narrowed direct bandgap manifest greatly boosted electrochemical performance as zinc‐ion battery cathodes. Specifically, the Mn0.15V2O5·nH2O electrode shows a high specific capacity of 367 mAh g?1 at a current density of 0.1 A g?1 as well as excellent retentive capacities of 153 and 122 mAh g?1 after 8000 cycles at high current densities up to 10 and 20 A g?1, respectively. Even at a low temperature of ?20 °C, a reversible specific capacity of 100 mAh g?1 can be achieved at a current density of 2.0 A g?1 after 3000 cycles. The superior electrochemical performance originates from the synergistic effects between the layered nanostructures and interlayer doping of Mn2+ ions and water molecules, which can enhance the electrons/ions transport kinetics and structural stability during cycling. With the aid of various ex situ characterization technologies and density functional theory calculations, the zinc‐ion storage mechanism can be revealed, which provides fundamental guidelines for developing high‐performance cathodes for ZIBs.  相似文献   

20.
Solid‐state lithium (Li) batteries using solid electrolytes and Li anodes are highly desirable because of their high energy densities and intrinsic safety. However, low ambient‐temperature conductivity and poor interface compatibility of solid electrolytes as well as Li dendrite formation cause large polarization and poor cycling stability. Herein, a high transference number intercalated composite solid electrolyte (CSE) is prepared by the combination of a solution‐casting and hot‐pressing method using layered lithium montmorillonite, poly(ethylene carbonate), lithium bis(fluorosulfonyl)imide, high‐voltage fluoroethylene carbonate additive, and poly(tetrafluoroethylene) binder. The electrolyte presents high ionic conductivity (3.5 × 10?4 S cm?1), a wide electrochemical window (4.6 V vs Li+/Li), and high ionic transference number (0.83) at 25 °C. In addition, a 3D Li anode is also fabricated via a facile thermal infusion strategy. The synergistic effect of high transference number intercalated electrolyte and 3D Li anode is more favorable to suppress Li dendrites in a working battery. The solid‐state batteries based on LiFePO4 (Al2O3 @ LiNi0.5Co0.2Mn0.3O2), CSE, and 3D Li deliver admirable cycling stability with discharge capacity 145.9 mAh g?1 (150.7 mAh g?1) and capacity retention 91.9% after 200 cycles at 0.5 C (92.0% after 100 cycles at 0.2 C) at 25 °C. This work affords a splendid strategy for high‐performance solid‐state battery.  相似文献   

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