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1.
H2V3O8 Nanowire/Graphene Electrodes for Aqueous Rechargeable Zinc Ion Batteries with High Rate Capability and Large Capacity
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Qiang Pang Congli Sun Yanhao Yu Kangning Zhao Ziyi Zhang Paul M. Voyles Gang Chen Yingjin Wei Xudong Wang 《Liver Transplantation》2018,8(19)
Aqueous rechargeable zinc ion batteries are considered a promising candidate for large‐scale energy storage owing to their low cost and high safety nature. A composite material comprised of H2V3O8 nanowires (NWs) wrapped by graphene sheets and used as the cathode material for aqueous rechargeable zinc ion batteries is developed. Owing to the synergistic merits of desirable structural features of H2V3O8 NWs and high conductivity of the graphene network, the H2V3O8 NW/graphene composite exhibits superior zinc ion storage performance including high capacity of 394 mA h g?1 at 1/3 C, high rate capability of 270 mA h g?1 at 20 C and excellent cycling stability of up to 2000 cycles with a capacity retention of 87%. The battery offers a high energy density of 168 W h kg?1 at 1/3 C and a high power density of 2215 W kg?1 at 20 C (calculated based on the total weight of H2V3O8 NW/graphene composite and the theoretically required amount of Zn). Systematic structural and elemental characterization confirm the reversible Zn2+ and water cointercalation electrochemical reaction mechanism. This work brings a new prospect of designing high‐performance aqueous rechargeable zinc ion batteries for grid‐scale energy storage. 相似文献
2.
Fabrication of Hierarchical Potassium Titanium Phosphate Spheroids: A Host Material for Sodium‐Ion and Potassium‐Ion Storage
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Zhixuan Wei Dongxue Wang Malin Li Yu Gao Chunzhong Wang Gang Chen Fei Du 《Liver Transplantation》2018,8(27)
Identifying suitable electrode materials for sodium‐ion and potassium‐ion storage holds the key to the development of earth‐abundant energy‐storage technologies. This study reports an anode material based on self‐assembled hierarchical spheroid‐like KTi2(PO4)3@C nanocomposites synthesized via an electrospray method. Such an architecture synergistically combines the advantages of the conductive carbon network and allows sufficient space for the infiltration of the electrolyte from the porous structure, leading to an impressive electrochemical performance, as reflected by the high reversible capacity (283.7 mA h g?1 for Na‐ion batteries; 292.7 mA h g?1 for K‐ion batteries) and superior rate capability (136.1 mA h g?1 at 10 A g?1 for Na‐ion batteries; 133.1 mA h g?1 at 1 A g?1 for K‐ion batteries) of the resulting material. Moreover, the different ion diffusion behaviors in the two systems are revealed to account for the difference in rate performance. These findings suggest that KTi2(PO4)3@C is a promising candidate as an anode material for sodium‐ion and potassium‐ion batteries. In particular, the present synthetic approach could be extended to other functional electrode materials for energy‐storage materials. 相似文献
3.
Jingyang Wang Yan Wang Dong‐Hwa Seo Tan Shi Shouping Chen Yaosen Tian Haegyeom Kim Gerbrand Ceder 《Liver Transplantation》2020,10(10)
Over the last decade, Na‐ion batteries have been extensively studied as low‐cost alternatives to Li‐ion batteries for large‐scale grid storage applications; however, the development of high‐energy positive electrodes remains a major challenge. Materials with a polyanionic framework, such as Na superionic conductor (NASICON)‐structured cathodes with formula NaxM2(PO4)3, have attracted considerable attention because of their stable 3D crystal structure and high operating potential. Herein, a novel NASICON‐type compound, Na4MnCr(PO4)3, is reported as a promising cathode material for Na‐ion batteries that deliver a high specific capacity of 130 mAh g?1 during discharge utilizing high‐voltage Mn2+/3+ (3.5 V), Mn3+/4+ (4.0 V), and Cr3+/4+ (4.35 V) transition metal redox. In addition, Na4MnCr(PO4)3 exhibits a high rate capability (97 mAh g?1 at 5 C) and excellent all‐temperature performance. In situ X‐ray diffraction and synchrotron X‐ray diffraction analyses reveal reversible structural evolution for both charge and discharge. 相似文献
4.
Yanyi Liu Michael Clark Qifeng Zhang Danmei Yu Dawei Liu Jun Liu Guozhong Cao 《Liver Transplantation》2011,1(2):194-202
Nanostructured V2O5 thin films have been prepared by means of cathodic deposition from an aqueous solution made from V2O5 and H2O2 directly on fluorine‐doped tin oxide coated (FTO) glasses followed by annealing at 500°C in air, and studied as film electrodes for lithium ion batteries. XPS results show that the as‐deposited films contained 15% V4+, however after annealing all the vanadium is oxidized to V5+. The crystallinity, surface morphology, and microstructures of the films have been investigated by means of XRD, SEM, and AFM. The V2O5 thin film electrodes show excellent electrochemical properties as cathodes for lithium ion intercalation: a high initial discharge capacity of 402 mA h g?1 and 240 mA h g?1 is retained after over 200 cycles with a discharging rate of 200 mA g?1 (1.3 C). The specific energy density is calculated as 900 W h kg?1 for the 1st cycle and 723 W h kg?1 for the 180th cycle when the films are tested at 200 mA g?1 (1.3 C). When discharge/charge is carried out at a high current density of 10.5 A g?1 (70 C), the thin film electrodes retain a good discharge capacity of 120 mA h g?1, and the specific power density is over 28 kW kg?1. 相似文献
5.
Xinxin Cao Anqiang Pan Sainan Liu Jiang Zhou Site Li Guozhong Cao Jun Liu Shuquan Liang 《Liver Transplantation》2017,7(20)
Sodium (Na) super ion conductor structured Na3V2(PO4)3 (NVP) is extensively explored as cathode material for sodium‐ion batteries (SIBs) due to its large interstitial channels for Na+ migration. The synthesis of 3D graphene‐like structure coated on NVP nanoflakes arrays via a one‐pot, solid‐state reaction in molten hydrocarbon is reported. The NVP nanoflakes are uniformly coated by the in situ generated 3D graphene‐like layers with the thickness of 3 nm. As a cathode material, graphene covered NVP nanoflakes exhibit excellent electrochemical performances, including close to theoretical reversible capacity (115.2 mA h g?1 at 1 C), superior rate capability (75.9 mA h g?1 at 200 C), and excellent cyclic stability (62.5% of capacity retention over 30000 cycles at 50 C). Furthermore, the 3D graphene‐like cages after removing NVP also serve as a good anode material and deliver a specific capacity of 242.5 mA h g?1 at 0.1 A g?1. The full SIB using these two cathode and anode materials delivers a high specific capacity (109.2 mA h g?1 at 0.1 A g?1) and good cycling stability (77.1% capacity retention over 200 cycles at 0.1 A g?1). 相似文献
6.
Hierarchically Porous Li4Ti5O12 Anode Materials for Li‐ and Na‐Ion Batteries: Effects of Nanoarchitectural Design and Temperature Dependence of the Rate Capability
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George Hasegawa Kazuyoshi Kanamori Tsutomu Kiyomura Hiroki Kurata Kazuki Nakanishi Takeshi Abe 《Liver Transplantation》2015,5(1)
Integrated design of both porous structure and crystalline morphology is expected to open up the way to a new class of materials. This report demonstrates new nanostructured Li4Ti5O12 materials with hierarchically porous structures and flower‐like morphologies. Electrochemical studies of the electrodes of Li‐ion and Na‐ion batteries clearly reveal the advantage of nanoarchitectural design of active materials. In addition, the temperature dependence of Na+‐insertion/extraction capacity in relation to Li4Ti5O12 electrodes is for the first time evaluated and it is found that elevation of the cell operating temperature effectively improves the rate capability of the Na‐ion batteries. Based on the new findings, it is suggested that specially designed Li4Ti5O12 materials allow for high‐performance Na‐ion batteries that are available as large‐scale storage devices for applications such as automotive and stationary energy storage. 相似文献
7.
Jie Zhang Ting He Wei Zhang Jinzhi Sheng Ibrahim Saana Amiinu Zongkui Kou Jinlong Yang Liqiang Mai Shichun Mu 《Liver Transplantation》2017,7(5)
Searching for a new material to build the next‐generation rechargeable lithium‐ion batteries (LIBs) with high electrochemical performance is urgently required. Owing to the low‐cost, non‐toxicity, and high‐safety, the family of manganese oxide including the Na‐Mn‐O system is regarded as one of the most promising electrode materials for LIBs. Herein, a new strategy is carried out to prepare a highly porous and electrochemically active Na0.55Mn2O4·1.5H2O (SMOH) compound. As an anode material, the Na‐Mn‐O nanocrystal material dispersed within a carbon matrix manifests a high reversible capacity of 1015.5 mA h g?1 at a current density of 0.1 A g?1. Remarkably, a considerable capability of 546.8 mA h g?1 remains even after 2000 discharge/charge cycles at the higher current density of 4 A g?1, indicating a splendid cyclability. The exceptional electrochemical properties allow SMOH to be a promising anode material toward LIBs. 相似文献
8.
A Novel High Capacity Positive Electrode Material with Tunnel‐Type Structure for Aqueous Sodium‐Ion Batteries
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Yuesheng Wang Linqin Mu Jue Liu Zhenzhong Yang Xiqian Yu Lin Gu Yong‐Sheng Hu Hong Li Xiao‐Qing Yang Liquan Chen Xuejie Huang 《Liver Transplantation》2015,5(22)
Aqueous sodium‐ion batteries have shown desired properties of high safety characteristics and low‐cost for large‐scale energy storage applications such as smart grid, because of the abundant sodium resources as well as the inherently safer aqueous electrolytes. Among various Na insertion electrode materials, tunnel‐type Na0.44MnO2 has been widely investigated as a positive electrode for aqueous sodium‐ion batteries. However, the low achievable capacity hinders its practical applications. Here, a novel sodium rich tunnel‐type positive material with a nominal composition of Na0.66[Mn0.66Ti0.34]O2 is reported. The tunnel‐type structure of Na0.44MnO2 obtained for this compound is confirmed by X‐ray diffraction and atomic‐scale spherical aberration‐corrected scanning transmission electron microscopy/electron energy‐loss spectrum. When cycled as positive electrode in full cells using NaTi2(PO4)3/C as negative electrode in 1 m Na2SO4 aqueous electrolyte, this material shows the highest capacity of 76 mAh g?1 among the Na insertion oxides with an average operating voltage of 1.2 V at a current rate of 2 C. These results demonstrate that Na0.66[Mn0.66Ti0.34]O2 is a promising positive electrode material for rechargeable aqueous sodium‐ion batteries. 相似文献
9.
Na‐ion technology is increasingly studied as a low‐cost solution for grid storage applications. Many positive electrode materials have been reported, mainly among layered oxides and polyanionic compounds. The vanadium oxy/flurophosphate solid solution Na3V2(PO4)2F3‐y O2y (0 ≤ y ≤ 1), in particular, has proven the ability to deliver ≈500 Wh kg‐1, operating on the V3+/V4+ (y = 0) or V4+/V5+ redox couples (y = 1). This paper reports here on a significant increase in specific energy by enabling sodium insertion into Na3V2(PO4)2FO2 to reach Na4V2(PO4)2FO2 upon discharge. This occurs at ≈1.6 V and increases the theoretical specific energy to 600 Wh kg?1, rivaling that of several Li‐ion battery cathodes. This improvement is achieved by the judicious modification of the composition either as O for F substitution, or Al for V substitution, both of which disrupt Na‐ion ordering and thereby enable insertion of the 4th Na. This paper furthermore shows from operando X‐Ray Diffraction (XRD) that this energy is obtained in the cycling range Na4V2(PO4)2FO2–NaV2(PO4)2FO2 with a very small overall volume change of 1.7%, which is one of the smallest volume changes for Na‐ion cathodes and which is a crucial requisite for stable long‐term cycling. 相似文献
10.
A Practicable Li/Na‐Ion Hybrid Full Battery Assembled by a High‐Voltage Cathode and Commercial Graphite Anode: Superior Energy Storage Performance and Working Mechanism
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Jin‐Zhi Guo Yang Yang Dao‐Sheng Liu Xing‐Long Wu Bao‐Hua Hou Wei‐Lin Pang Ke‐Cheng Huang Jing‐Ping Zhang Zhong‐Min Su 《Liver Transplantation》2018,8(10)
With the rapidly growing demand for low‐cost and safe energy storage, the advanced battery concepts have triggered strong interests beyond the state‐of‐the‐art Li‐ion batteries (LIBs). Herein, a novel hybrid Li/Na‐ion full battery (HLNIB) composed of the high‐energy and lithium‐free Na3V2(PO4)2O2F (NVPOF) cathode and commercial graphite anode mesophase carbon micro beads is for the first time designed. The assembled HLNIBs exhibit two high working voltage at about 4.05 and 3.69 V with a specific capacity of 112.7 mA h g?1. Its energy density can reach up to 328 W h kg?1 calculated from the total mass of both cathode and anode materials. Moreover, the HLNIBs show outstanding high‐rate capability, long‐term cycle life, and excellent low‐temperature performance. In addition, the reaction kinetics and Li/Na‐insertion/extraction mechanism into/out NVPOF is preliminarily investigated by the galvanostatic intermittent titration technique and ex situ X‐ray diffraction. This work provides a new and profound direction to develop advanced hybrid batteries. 相似文献
11.
Yalong Jiang Yuanhao Shen Jun Dong Shuangshuang Tan Qiulong Wei Fangyu Xiong Qidong Li Xiaobin Liao Ziang Liu Qinyou An Liqiang Mai 《Liver Transplantation》2019,9(27)
Sodium‐based energy storage technologies are potential candidates for large‐scale grid applications owing to the earth abundance and low cost of sodium resources. Transition metal phosphides, e.g. MoP, are promising anode materials for sodium‐ion storage, while their detailed reaction mechanisms remain largely unexplored. Herein, the sodium‐ion storage mechanism of hexagonal MoP is systematically investigated through experimental characterizations, density functional theory calculations, and kinetics analysis. Briefly, it is found that the naturally covered surface amorphous molybdenum oxides layers on the MoP grains undergo a faradaic redox reaction during sodiation and desodiation, while the inner crystalline MoP remains unchanged. Remarkably, the MoP anode exhibits a pseudocapacitive‐dominated behavior, enabling the high‐rate sodium storage performance. By coupling the pseudocapacitive anode with a high‐rate‐battery‐type Na3V2O2(PO4)2F@rGO cathode, a novel sodium‐ion full cell delivers a high energy density of 157 Wh kg?1 at 97 W kg?1 and even 52 Wh kg?1 at 9316 W kg?1. These findings present the deep understanding of the sodium‐ion storage mechanism in hexagonal MoP and offer a potential route for the design of high‐rate sodium‐ion storage materials and devices. 相似文献
12.
Open‐Structured V2O5·nH2O Nanoflakes as Highly Reversible Cathode Material for Monovalent and Multivalent Intercalation Batteries
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Huali Wang Xuanxuan Bi Ying Bai Chuan Wu Sichen Gu Shi Chen Feng Wu Khalil Amine Jun Lu 《Liver Transplantation》2017,7(14)
The high‐capacity cathode material V2O5·n H2O has attracted considerable attention for metal ion batteries due to the multielectron redox reaction during electrochemical processes. It has an expanded layer structure, which can host large ions or multivalent ions. However, structural instability and poor electronic and ionic conductivities greatly handicap its application. Here, in cell tests, self‐assembly V2O5·n H2O nanoflakes shows excellent electrochemical performance with either monovalent or multivalent cation intercalation. They are directly grown on a 3D conductive stainless steel mesh substrate via a simple and green hydrothermal method. Well‐layered nanoflakes are obtained after heat treatment at 300 °C (V2O5·0.3H2O). Nanoflakes with ultrathin flower petals deliver a stable capacity of 250 mA h g?1 in a Li‐ion cell, 110 mA h g?1 in a Na‐ion cell, and 80 mA h g?1 in an Al‐ion cell in their respective potential ranges (2.0–4.0 V for Li and Na‐ion batteries and 0.1–2.5 V for Al‐ion battery) after 100 cycles. 相似文献
13.
Md. Mokhlesur Rahman Jia‐Zhao Wang Mohd Faiz Hassan David Wexler Hua Kun Liu 《Liver Transplantation》2011,1(2):212-220
This work introduces an effective, inexpensive, and large‐scale production approach to the synthesis of a carbon coated, high grain boundary density, dual phase Li4Ti5O12‐TiO2 nanocomposite anode material for use in rechargeable lithium‐ion batteries. The microstructure and morphology of the Li4Ti5O12‐TiO2‐C product were characterized systematically. The Li4Ti5O12‐TiO2‐C nanocomposite electrode yielded good electrochemical performance in terms of high capacity (166 mAh g?1 at a current density of 0.5 C), good cycling stability, and excellent rate capability (110 mAh g?1 at a current density of 10 C up to 100 cycles). The likely contributing factors to the excellent electrochemical performance of the Li4Ti5O12‐TiO2‐C nanocomposite could be related to the improved morphology, including the presence of high grain boundary density among the nanoparticles, carbon layering on each nanocrystal, and grain boundary interface areas embedded in a carbon matrix, where electronic transport properties were tuned by interfacial design and by varying the spacing of interfaces down to the nanoscale regime, in which the grain boundary interface embedded carbon matrix can store electrolyte and allows more channels for the Li+ ion insertion/extraction reaction. This research suggests that carbon‐coated dual phase Li4Ti5O12‐TiO2 nanocomposites could be suitable for use as a high rate performance anode material for lithium‐ion batteries. 相似文献
14.
Abdulrahman Shahul Hameed Akihiro Katogi Kei Kubota Shinichi Komaba 《Liver Transplantation》2019,9(45)
K‐ion batteries (KIBs) are promising for large‐scale energy storage owing to various advantages like the high abundance of potassium resources in the Earth's crust, high operational potentials, and high power due to fast diffusion of K+ ions. However, to realize the practical application of KIBs, electrode materials are needed with high operational voltage, good capacity, long cycle life, and low‐cost. This work reports a layered open framework material, K2[(VOHPO4)2(C2O4)], composited with reduced graphene oxide (rGO) as a 4 V positive electrode material for KIBs. The material is prepared by a simple precipitation reaction at room temperature. The material demonstrates reversible K‐extraction/insertion with conventional carbonate ester KPF6 solutions; however, with low specific capacity and low Coulombic efficiency. A high discharge capacity of >100 mAh g?1 with good cycling stability and higher Coulombic efficiency is achieved in a highly concentrated electrolyte, 7 mol kg?1 of potassium bis(fluorosulfonyl)amide (KFSA) in dimethoxyethane (DME) at 0.1 C rate. Due to the facile migration of K+ ions in the framework, the material exhibits excellent rate capability with a discharge capacity of 80 mAh g?1 at 10 C rate, and a good capacity retention of 67% after 500 cycles at 2 C rate. 相似文献
15.
An Ion‐Exchange Promoted Phase Transition in a Li‐Excess Layered Cathode Material for High‐Performance Lithium Ion Batteries
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Jianqing Zhao Ruiming Huang Wenpei Gao Jian‐Min Zuo Xiao Feng Zhang Scott T. Misture Yuan Chen Jenny V. Lockard Boliang Zhang Shengmin Guo Mohammad Reza Khoshi Kerry Dooley Huixin He Ying Wang 《Liver Transplantation》2015,5(9)
A new approach to intentionally induce phase transition of Li‐excess layered cathode materials for high‐performance lithium ion batteries is reported. In high contrast to the limited layered‐to‐spinel phase transformation that occurred during in situ electrochemical cycles, a Li‐excess layered Li[Li0.2Mn0.54Ni0.13Co0.13]O2 is completely converted to a Li4Mn5O12‐type spinel product via ex situ ion‐exchanges and a post‐annealing process. Such a layered‐to‐spinel phase conversion is examined using in situ X‐ray diffraction and in situ high‐resolution transmission electron microscopy. It is found that generation of sufficient lithium ion vacancies within the Li‐excess layered oxide plays a critical role for realizing a complete phase transition. The newly formed spinel material exhibits initial discharge capacities of 313.6, 267.2, 204.0, and 126.3 mAh g?1 when cycled at 0.1, 0.5, 1, and 5 C (1 C = 250 mA g?1), respectively, and can retain a specific capacity of 197.5 mAh g?1 at 1 C after 100 electrochemical cycles, demonstrating remarkably improved rate capability and cycling stability in comparison with the original Li‐excess layered cathode materials. This work sheds light on fundamental understanding of phase transitions within Li‐excess layered oxides. It also provides a novel route for tailoring electrochemical performance of Li‐excess layered cathode materials for high‐capacity lithium ion batteries. 相似文献
16.
Nanoparticles Encapsulated in Porous Carbon Matrix Coated on Carbon Fibers: An Ultrastable Cathode for Li‐Ion Batteries
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Rujia Zou Qian Liu Guanjie He Muk Fung Yuen Kaibing Xu Junqing Hu Ivan P. Parkin Chun‐Sing Lee Wenjun Zhang 《Liver Transplantation》2017,7(2)
Nanostructured V2O5 is emerging as a new cathode material for lithium ion batteries for its distinctly high theoretic capacity over the current commercial cathodes. The main challenges associated with nanostructured V2O5 cathodes are structural degradation, instability of the solid‐electrolyte interface layer, and poor electron conductance, which lead to low capacity and rapid decay of cyclic stability. Here, a novel composite structure of V2O5 nanoparticles encapsulated in 3D networked porous carbon matrix coated on carbon fibers (V2O5/3DC‐CFs) is reported that effectively addresses the mentioned problems. Remarkably, the V2O5/3DC‐CF electrode exhibits excellent overall lithium‐storage performance, including high Coulombic efficiency, excellent specific capacity, outstanding cycling stability and rate property. A reversible capacity of ≈183 mA h g?1 is obtained at a high current density of 10 C, and the battery retains 185 mA h g?1 after 5000 cycles, which shows the best cycling stability reported to date among all reported cathodes of lithium ion batteries as per the knowledge. The outstanding overall properties of the V2O5/3DC‐CF composite make it a promising cathode material of lithium ion batteries for the power‐intensive energy storage applications. 相似文献
17.
Surface Mn Oxidation State Controlled Spinel LiMn2O4 as a Cathode Material for High‐Energy Li‐Ion Batteries
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Spinel lithium manganese oxide (LiMn2O4) has attracted much attention as a promising cathode material for large‐scale lithium ion batteries. However, its continuous capacity fading at elevated temperature is an obstacle to extended cycling in large‐scale applications. Here, surface Mn oxidation state controlled LiMn2O4 is synthesized by coating stoichiometric LiMn2O4 with a cobalt‐substituted spinel, for which stoichiometric LiMn2O4 is used as the starting material and onto which a LixMnyCozO4 layer is coated from an acetate‐based precursor solution. In the coated material, the concentrations of both cobalt and Mn4+ ions vary from the surface to the core. the former without any lattice mismatch between the coating layer and host material. Cycle tests are performed under severe conditions, namely, high temperature and intermittent high current load. During the first discharge cycle at 7 C and 60 °C, a high energy and power density are measured for the coated material, 419 and 3.16 Wh kg?1, respectively, compared with 343 and 3.03 Wh kg?1, respectively, for the bare material. After 65 cycles under severe conditions, the coated material retains 82% and ≈100% of the initial energy and power density, respectively, whereas the bare material retains only ≈68% and ≈97% thereof. 相似文献
18.
Ji Ung Choi Jae Hyeon Jo Yun Ji Park Kug‐Seung Lee Seung‐Taek Myung 《Liver Transplantation》2020,10(27)
Herein, P′2‐type Na0.67[Ni0.1Fe0.1Mn0.8]O2 is introduced as a promising new cathode material for sodium‐ion batteries (SIBs) that exhibits remarkable structural stability during repetitive Na+ de/intercalation. The O? Ni? O? Mn? O? Fe? O bond in the octahedra of transition‐metal layers is used to suppress the elongation of the Mn? O bond and to improve the electrochemical activity, leading to the highly reversible Na storage mechanism. A high discharge capacity of ≈220 mAh g?1 (≈605 Wh kg?1) is delivered at 0.05 C (13 mAg?1) with a high reversible capacity of ≈140 mAh g?1 at 3 C and excellent capacity retention of 80% over 200 cycles. This performance is associated with the reversible P′2–OP4 phase transition and small volume change upon charge and discharge (≈3%). The nature of the sodium storage mechanism in a full cell paired with a hard carbon anode reveals an unexpectedly high energy density of ≈542 Wh kg?1 at 0.2 C and good capacity retention of ≈81% for 500 cycles at 1 C (260 mAg?1). 相似文献
19.
Rechargeable aqueous batteries with Zn2+ as a working‐ion are promising candidates for grid‐scale energy storage because of their intrinsic safety, low‐cost, and high energy‐intensity. However, suitable cathode materials with excellent Zn2+‐storage cyclability must be found in order for Zinc‐ion batteries (ZIBs) to find practical applications. Herein, NaCa0.6V6O16·3H2O (NaCaVO) barnesite nanobelts are reported as an ultra‐stable ZIB cathode material. The original capacity reaches 347 mAh g?1 at 0.1 A g?1, and the capacity retention rate is 94% after 2000 cycles at 2 A g?1 and 83% after 10 000 cycles at 5 A g?1, respectively. Through a combined theoretical and experimental approach, it is discovered that the unique V3O8 layered structure in NaCaVO is energetically favorable for Zn2+ diffusion and the structural water situated between V3O8 layers promotes a fast charge‐transfer and bulk migration of Zn2+ by enlarging gallery spacing and providing more Zn‐ion storage sites. It is also found that Na+ and Ca2+ alternately suited in V3O8 layers are the essential stabilizers for the layered structure, which play a crucial role in retaining long‐term cycling stability. 相似文献
20.
While the practical application of electrode materials depends intensively on the Li+ ion storage mechanisms correlating ultimately with the coulombic efficiency, reversible capacity, and morphology variation of electrode material upon cycling, only intercalation‐type electrode materials have proven viable for commercialization up to now. This paper reviews the promising anode materials of metal vanadates (MxVyOz, M = Co, Cu, Mn, Fe, Zn, Ni, Li) that have high capacity, low cost, and abundant resource, and also discusses the related Li+ ion storage mechanism. It is concluded that most of these (MxVyOz, M = Co, Cu, Mn, Fe, Zn, Ni) exhibit irreversible redox reactions upon lithiation/delithiation accompanied by large volume expansion, which is not favorable for industrial applications. In particular, Li3VO4 with specific intercalation Li+ ion storage mechanism and compatible merits of safety and energy density exhibits great potential for practical application. This review systematically summarizes the latest progress in Li3VO4 research, including the representative fabrication approaches for advanced morphology and state‐of‐the‐art technologies to boost performance and the morphology variation associated with Li+ ion storage mechanisms. Furthermore, an outlook on where breakthroughs for Li3VO4 may be most likely achieved will be provided. 相似文献