首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
A flexible and wearable aqueous lithium‐ion battery is introduced based on spinel Li1.1Mn2O4 cathode and a carbon‐coated NASICON‐type LiTi2(PO4)3 anode (NASICON=sodium‐ion super ionic conductor). Energy densities of 63 Wh kg?1 or 124 mWh cm?3 and power densities of 3 275 W kg?1 or 11.1 W cm?3 can be obtained, which are seven times larger than the largest reported till now. The full cell can keep its capacity without significant loss under different bending states, which shows excellent flexibility. Furthermore, two such flexible cells in series with an operation voltage of 4 V can be compatible with current nonaqueous Li‐ion batteries. Therefore, such a flexible cell can potentially be put into practical applications for wearable electronics. In addition, a self‐chargeable unit is realized by integrating a single flexible aqueous Li‐ion battery with a commercial flexible solar cell, which may facilitate the long‐time outdoor operation of flexible and wearable electronic devices.  相似文献   

2.
Structural and morphological control is an effective approach for improvement of electrochemical properties in rechargeable batteries. One‐dimensionally assembled structure composed of NASICON‐type Na3V2(PO4)3 nanoparticles were fabricated through an electrospinning method to meet the requirements for the development of efficient electrode materials in Na‐ion batteries. High‐temperature treatment of electrospun precursor fibers under an argon flow provides a nonwoven fabric of nanowires comprising crystallographically oriented nanoparticles of NASICON‐type Na3V2(PO4)3 within a carbon sheath. The mesostructure comprising NASICON‐type Na3V2(PO4)3 and carbon give a short sodium‐ion transport pass and an efficient electron conduction pass. Electrochemical properties of NASICON‐type Na3V2(PO4)3 are improved on the basis of one‐dimensional nanostructures designed in the present study.  相似文献   

3.
Herein, we introduce a 4.0 V class high‐voltage cathode material with a newly recognized sodium superionic conductor (NASICON)‐type structure with cubic symmetry (space group P213), Na3V(PO3)3N. We synthesize an N‐doped graphene oxide‐wrapped Na3V(PO3)3N composite with a uniform carbon coating layer, which shows excellent rate performance and outstanding cycling stability. Its air/water stability and all‐climate performance were carefully investigated. A near‐zero volume change (ca. 0.40 %) was observed for the first time based on in situ synchrotron X‐ray diffraction, and the in situ X‐ray absorption spectra revealed the V3.2+/V4.2+ redox reaction with high reversibility. Its 3D sodium diffusion pathways were demonstrated with distinctive low energy barriers. Our results indicate that this high‐voltage NASICON‐type Na3V(PO3)3N composite is a competitive cathode material for sodium‐ion batteries and will receive more attention and studies in the future.  相似文献   

4.
Flexible lithium‐ion batteries are critical for the next‐generation electronics. However, during the practical application, they may break under deformations such as twisting and cutting, causing their failure to work or even serious safety problems. A new family of all‐solid‐state and flexible aqueous lithium ion batteries that can self‐heal after breaking has been created by designing aligned carbon nanotube sheets loaded with LiMn2O4 and LiTi2(PO4)3 nanoparticles on a self‐healing polymer substrate as electrodes, and a new kind of lithium sulfate/sodium carboxymethylcellulose serves as both gel electrolyte and separator. The specific capacity, rate capability, and cycling performance can be well maintained after repeated cutting and self‐healing. These self‐healing batteries are demonstrated to be promising for wearable devices.  相似文献   

5.
Li1 +x Ti2 − x Ga x (PO4)3(x= 0−0.2) NASICON double phosphates are prepared and studied by high-temperature X-ray diffraction, 7Li NMR spectroscopy, impedance spectroscopy, and calorimetry. Doping with Ga3+ cations increases cation mobility in LiTi2(PO4)3. Ion conductivity, NMR spectroscopy, and calorimetry data imply the occurrence of a phase transition in LiTi2(PO4)3 and in products of partial gallium-for-titanium substitution. Original Russian Text ? I.Yu. Pinus, I.V. Arkhangel’skii, N.A. Zhuravlev, A.B. Yaroslavtsev, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 8, pp. 1235–1239.  相似文献   

6.
Aqueous Na‐ or K‐ion batteries could virtually eliminate the safety and cost concerns raised from Li‐ion batteries, but their widespread applications have generally suffered from narrow electrochemical potential window (ca. 1.23 V) of aqueous electrolytes that leads to low energy density. Herein, by exploring optimized eutectic systems of Na and K salts with asymmetric imide anions, we discovered, for the first time, room‐temperature hydrate melts for Na and K systems, which are the second and third alkali metal hydrate melts reported since the first discovery of Li hydrate melt by our group in 2016. The newly discovered Na‐ and K‐ hydrate melts could significantly extend the potential window up to 2.7 and 2.5 V (at Pt electrode), respectively, owing to the merit that almost all water molecules participate in the Na+ or K+ hydration shells. As a proof‐of‐concept, a prototype Na3V2(PO4)2F3|NaTi2(PO4)3 aqueous Na‐ion full‐cell with the Na‐hydrate‐melt electrolyte delivers an average discharge voltage of 1.75 V, that is among the highest value ever reported for all aqueous Na‐ion batteries.  相似文献   

7.
Polyanionic LiTi2(PO4)3 material with 3D framework structure is intensively investigated to be used in lithium ion batteries. However, the LiTi2(PO4)3-based materials suffer from poor electronic conductivity hindering the application as electrode active materials. This work describes an effective and simple strategy to synthesize LiTi2(PO4)3/C core–shell structure without the addition of external carbon sources. This approach is achieved by a simple one-step solid state reaction using organometallic salt as raw material. The as-prepared LiTi2(PO4)3 exhibits uniform and thin carbon coating on the particle surface. The electrochemical properties of the LiTi2(PO4)3/C composite are investigated, and the results demonstrate that the as-prepared LiTi2(PO4)3/C shows good cycling performance and rate capability.  相似文献   

8.
Na‐ion batteries are becoming comparable to Li‐ion batteries because of their similar chemical characteristics and abundant sources of sodium. However, the materials production should be cost‐effective in order to meet the demand for large‐scale application. Here, a series of nanosized high‐performance cathode materials, Na3(VO1?xPO4)2F1+2x (0≤x≤1), has been synthesized by a solvothermal low‐temperature (60–120 °C) strategy without the use of organic ligands or surfactants. The as‐synthesized Na3(VOPO4)2F nanoparticles show the best Na‐storage performance reported so far in terms of both high rate capability (up to 10 C rate) and long cycle stability over 1200 cycles. To the best of our knowledge, the current developed synthetic strategy for Na3(VO1?xPO4)2F1+2x is by far one of the least expensive and energy‐consuming methods, much superior to the conventional high‐temperature solid‐state method.  相似文献   

9.
Aqueous zinc‐ion batteries (ZIBs) have become the highest potential energy storage system for large‐scale applications owing to the high specific capacity, good safety and low cost. In this work, a NASICON‐type Na3V2(PO4)3 cathode modified by a uniform carbon layer (NVP/C) has been synthesized via a facile solid‐state method and exhibited significantly improved electrochemical performance when working in an aqueous ZIB. Specifically, the NVP/C cathode shows an excellent rate capacity (e. g., 48 mAh g?1 at 1.0 A g?1). Good cycle stability is also achieved (e. g., showing a capacity retention of 88% after 2000 cycles at 1.0 A g?1). Furthermore, the Zn2+ (de)intercalation mechanism in the NVP cathode has been determined by various ex‐situ techniques. In addition, a Zn||NVP/C pouch cell has been assembled, delivering a high capacity of 89 mAhg?1 at 0.2 A g?1 and exhibiting a superior long cycling stability.  相似文献   

10.
A symmetric sodium‐ion battery with an aqueous electrolyte is demonstrated; it utilizes the NASICON‐structured Na3MnTi(PO4)3 as both the anode and the cathode. The NASICON‐structured Na3MnTi(PO4)3 possesses two electrochemically active transition metals with the redox couples of Ti4+/Ti3+ and Mn3+/Mn2+ working on the anode and cathode sides, respectively. The symmetric cell based on this bipolar electrode material exhibits a well‐defined voltage plateau centered at about 1.4 V in an aqueous electrolyte with a stable cycle performance and superior rate capability. The advent of aqueous symmetric sodium‐ion battery with high safety and low cost may provide a solution for large‐scale stationary energy storage.  相似文献   

11.
Comparison of the electrochemical insertion of lithium into ATi2(PS4)3 with A = Li, Na, Ag and ATi2(PO4)3 with Li, Ag is striking. Whereas only four lithium per formula unit (Li/f.u.) can be inserted reversibly into the phosphates, up to 7 and 10 Li/f.u. can be inserted reversibly in the thiophosphates with A = Li and Ag. Moreover, the Ag+ to Ag0 reduction in AgTi2(PO4)3 is not reversible, but in AgTi2(PS4)3 it is reversible. Strong hybridization of the Ag-5s and host antibonding bands stabilizes the formal valences Ag0, Ti+, and (PS4)4− in the discharged state of AgTi2(PS4)3; but only the formal valence Ti2+ is accessible in LiTi2(PS4)3. Unfortunately the large volume change associated with the lithium insertion renders the structure progressively more amorphous on cycling, which causes the capacity to fade quite dramatically on further cycling. The thiophosphates transform to the phosphates on heating in air.  相似文献   

12.
Herein, mesoporous sodium vanadium phosphate nanoparticles with highly sp2‐coordinated carbon coatings (meso‐Na3V2(PO4)3/C) were successfully synthesized as efficient cathode material for rechargeable sodium‐ion batteries by using ascorbic acid as both the reductant and carbon source, followed by calcination at 750 °C in an argon atmosphere. Their crystalline structure, morphology, surface area, chemical composition, carbon nature and amount were systematically explored. Following electrochemical measurements, the resultant meso‐Na3V2(PO4)3/C not only delivered good reversible capacity (98 mAh g?1 at 0.1 A g?1) and superior rate capability (63 mAh g?1 at 1 A g?1) but also exhibited comparable cycling performance (capacity retention: ≈74 % at 450 cycles at 0.4 A g?1). Moreover, the symmetrical sodium‐ion full cell with excellent reversibility and cycling stability was also achieved (capacity retention: 92.2 % at 0.1 A g?1 with 99.5 % coulombic efficiency after 100 cycles). These attributes are ascribed to the distinctive mesostructure for facile sodium‐ion insertion/extraction and their continuous sp2‐coordinated carbon coatings, which facilitate electronic conduction.  相似文献   

13.
Sodium‐ion batteries are a very promising alternative to lithium‐ion batteries because of their reliance on an abundant supply of sodium salts, environmental benignity, and low cost. However, the low rate capability and poor long‐term stability still hinder their practical application. A cathode material, formed of RuO2‐coated Na3V2O2(PO4)2F nanowires, has a 50 nm diameter with the space group of I4/mmm. When used as a cathode material for Na‐ion batteries, a reversible capacity of 120 mAh g?1 at 1 C and 95 mAh g?1 at 20 C can be achieved after 1000 charge–discharge cycles. The ultrahigh rate capability and enhanced cycling stability are comparable with high performance lithium cathodes. Combining first principles computational investigation with experimental observations, the excellent performance can be attributed to the uniform and highly conductive RuO2 coating and the preferred growth of the (002) plane in the Na3V2O2(PO4)2F nanowires.  相似文献   

14.
Li1.3Zr1.7Al0.3(PO4)3的离子交换特性   总被引:1,自引:0,他引:1  
锂作为21世纪推动科学技术发展的重要元素之一,被誉为“工业味精”、“能源之星”。目前锂及其相关盐类材料已成为信息产业、核能源、航空航天技术、新型材料及军事科技等行业重点开发领域,具有极高科学价值和广阔商业前景[1 ̄4]。氯化锂是电解制金属锂的主要原料,它的纯度是电  相似文献   

15.
The rechargeable aqueous metal‐ion battery (RAMB) has attracted considerable attention due to its safety, low costs, and environmental friendliness. Yet the poor‐performance electrode materials lead to a low feasibility of practical application. A hybrid aqueous battery (HAB) built from electrode materials with selective cation channels could increase the electrode applicability and thus enlarge the application of RAMB. Herein, we construct a high‐voltage K–Na HAB based on K2FeFe(CN)6 cathode and carbon‐coated NaTi2(PO4)3 (NTP/C) anode. Due to the unique cation selectivity of both materials and ultrafast ion conduction of NTP/C, the hybrid battery delivers a high capacity of 160 mAh g?1 at a 0.5 C rate. Considerable capacity retention of 94.3 % is also obtained after 1000 cycles at even 60 C rate. Meanwhile, high energy density of 69.6 Wh kg?1 based on the total mass of active electrode materials is obtained, which is comparable and even superior to that of the lead acid, Ni/Cd, and Ni/MH batteries.  相似文献   

16.
Lithium‐ion batteries (LIBs) are being used to power the commercial electric vehicles (EVs). However, the charge/discharge rate and life of current LIBs still cannot satisfy the further development of EVs. Furthermore, the poor low‐temperature performance of LIBs limits their application in cold climates and high altitude areas. Herein, a simple prelithiation method is developed to fabricate a new LIB. In this strategy, a Li3V2(PO4)3 cathode and a pristine hard carbon anode are used to form a primary cell, and the initial Li+ extraction from Li3V2(PO4)3 is used to prelithiate the hard carbon. Then, the self‐formed Li2V2(PO4)3 cathode and prelithiated hard carbon anode are used to form a 4 V LIB. The LIB exhibits a maximum energy density of 208.3 Wh kg−1, a maximum power density of 8291 W kg−1 and a long life of 2000 cycles. When operated at −40 °C, the LIB can keep 67 % capacity of room temperature, which is much better than conventional LIBs.  相似文献   

17.
研究了LiZr2(PO4)3在水溶液中的Na/Li和Ag/Li离子交换行为.结果表明,LiZr2(PO4)3对Na+和Ag+离子均具有很高的选择性,且对Ag+的选择性高于Na+.LiZr2(PO4)3与Ag+的离子交换反应是通过形成固溶体的形式进行的,而与Na+的离子交换反应则是通过置换进行的.温度升高有利于提高LiZr2(PO4)3上Na/Li和Ag/Li的离子交换反应速度.  相似文献   

18.
Sodium‐ion batteries are similar in concept and function to lithium‐ion batteries, but their development and commercialization lag far behind. One obstacle is the lack of a standard reference electrode. Unlike Li foil reference electrodes, sodium is not easily processable or moldable and it deforms easily. Herein we fabricate a processable and moldable composite Na metal anode made from Na and reduced graphene oxide (r‐GO). With only 4.5 % percent r‐GO, the composite anodes had improved hardness, strength, and stability to corrosion compared to Na metal, and can be engineered to various shapes and sizes. The plating/stripping cycling of the composite anode was significantly extended in both ether and carbonate electrolytes giving less dendrite formation. We used the composite anode in both Na‐O2 and Na‐Na3V2(PO4)3 full cells.  相似文献   

19.
Na superionic conductor (NASICON) structured cathode materials with robust structural stability and large Na+ diffusion channels have aroused great interest in sodium-ion batteries (SIBs). However, most of NASICON-type cathode materials exhibit redox reaction of no more than three electrons per formula, which strictly limits capacity and energy density. Herein, a series of NASICON-type Na3+xMnTi1−xVx(PO4)3 cathode materials are designed, which demonstrate not only a multi-electron reaction but also high voltage platform. With five redox couples from V5+/4+ (≈4.1 V), Mn4+/3+ (≈4.0 V), Mn3+/2+ (≈3.6 V), V4+/3+ (≈3.4 V), and Ti4+/3+ (≈2.1 V), the optimized material, Na3.2MnTi0.8V0.2(PO4)3, realizes a reversible 3.2-electron redox reaction, enabling a high discharge capacity (172.5 mAh g−1) and an ultrahigh energy density (527.2 Wh kg−1). This work sheds light on the rational construction of NASICON-type cathode materials with multi-electron redox reaction for high-energy SIBs.  相似文献   

20.

A new type of three-dimensional (3D) oxy-phosphate materials are explored for the application of Li and Na batteries. The molybdenum tungsten oxy phosphate, MoWO3(PO4)2, was synthesized by solid-state method and evaluated for Li/Na insertion/de-insertion electrode material for the first time. The cell at charged state (vs. Li+/Li) showed a discharge capacity of 786 mAh g−1 within the voltage window of 0.3 V with amorphization of crystalline MoWO3(PO4)2 as observed from ex-situ powder XRD analysis. The structural integrity was revealed in this material, even with nearly more than 5 Li+ ions into the lattice, leading to the discharge capacity of 250 mAh g−1. The reversible charge/discharge behavior with insertion/de-insertion of 2.4 Li+ ions in the voltage range of 1.65 − 3.5 V resulted in 110 and 95 mAh g−1 at C/10 and C/5 rates, respectively. On the other hand, poor cycling performance was noticed for Na ion insertion and desertion, with a discharge capacity of 250 mAh/g within the voltage range of 0.3 − 3.5 V (vs. Na+/Na).

  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号