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1.
《Ceramics International》2021,47(19):26732-26737
Herein, we propose a new anode material, PbNb2O6, for use in lithium-ion batteries. PbNb2O6 can be synthesized via a simple and traditional solid-state method. The as-prepared powder exhibits an average size distribution of about 0.5 μm. When tested in a lithium-ion cell, the PbNb2O6 electrode can exhibit a charge capacity of 245.2 mAh g−1 at 200 mA g−1, and after 80 cycles, the capacity can retain a charge capacity of 181.4 mAh g−1, showing 0.32% capacity fading per cycle. Furthermore, the capacity of the PbNb2O6 electrode is 223.1 mAh g−1, even when cycled at 1000 mA g−1, and a capacity of 150.7 mAh g−1 is maintained up to 500 cycles. In addition, the lithiation mechanism of PbNb2O6 is investigated via various techniques. Interestingly, PbNb2O6 exhibits high capacity without the contribution of two redox couples of niobium after the initial cycles. Finally, all Results suggest that PbNb2O6 has potential for use as an electrode in lithium-ion batteries.  相似文献   

2.
《Ceramics International》2021,47(22):31597-31602
Lithium-ion batteries (LIBs) present the advantages of long cycle life, high voltage, and energy density and are widely made in the field of energy storage. LiVOPO4 (LVOP), a cathode material used in LIBs, has a high conceptual capacity of 159 mAh g−1 and high operating voltage of 3.9 V. However, its low electrical conductivity and cycle performance limit its commercial applications. According to the X-ray diffraction results, orthogonal crystal LVOP and monoclinic crystal Li3V2(PO4)3 (LVP) coexisted in the synthesised composite material. The transmission electron microscopy results also indicated that the LVOP and LVP phases coexist, which were coated by carbon layer of about 2.5 nm. The discharge of LVOP–LVP composite material initially was 143.2 mAh g−1, and that after 120 cycles was 132.2 mAh g−1 (at 0.1 C and 3–4.5 V). Thus, the electronic conductivity and first discharge specific capacity of the material enhanced due to the introduction of fast ion conductor LVP into LVOP. Electrochemical performance improved because the introduction of LVP led to an increase in Li+ pervasion channels in the original material and the acceleration of the Li+ transmission speed.  相似文献   

3.
《Ceramics International》2020,46(6):7625-7633
A long-lived cycling property is an important factor for the extensive use of the lithium-ion batteries. In this study, a NaAlO2 layer was initially coated on the LiNi0.5Co0.2Mn0.3O2 surface. Electrochemical tests indicate that the coated surface achieves better cycling stability and a higher capacity at 25 °C. In addition, the 1 wt % NaAlO2-coated sample exhibits the best performance, and it also exhibits a discharge specific capacity of 189.6 mAh∙g−1 at 0.1C in the first cycle. After 800 cycles at 1C, the capacity retention of the 1 wt % NaAlO2-coated sample is approximately 73.31%, a value that is 21.26% higher than the pristine sample. The electrochemical impedance spectroscopy (EIS) analysis reveals a decrease in the LiNi0.5Co0.2Mn0.3O2 charge transfer impedance and a significant increase in lithium ion diffusion after the application of the NaAlO2 coating. The high ion diffusion coefficient and low charge transfer impedance are conducive to the better rate performance of NaAlO2-coated LiNi0.5Co0.2Mn0.3O2.  相似文献   

4.
The LiNi0.80Co0.15Al0.05O2 (NCA) cathode is endowed with a high energy density and excellent cycling performance. However, the preparation conditions for this material are quite harsh. Therefore, it is rather significant to obtain well-qualified NCA by simple solid-phase synthesis. In this study, the solid-phase synthesis of NCA cathode material is carried out by mixing two types of raw materials via stirring or sand milling. The effects of different particle sizes on the structure and morphology of NCA materials are analyzed. Owing to the different particle sizes of the raw materials, the diffusion path of Li+ between the solid phases differs greatly. The XRD results show that the samples mixed by stirring have a worse cation mixture than those mixed by sand milling due to the larger particle size, smaller sintering surface energy, and insufficient sintering strength. The electrochemical results show that the sample mixed by sand milling has a higher specific capacity at a low rate, the initial discharge capacity is 199.22?mAh?g?1, and the capacity retention rate is 86.9% after 50 cycles. In contrast, the initial discharge capacity of the sample mixed by stirring is 184.86?mAh?g?1, and the capacity is 171.93?mAh?g?1 after 50 cycles with a 93.0% capacity retention rate.  相似文献   

5.
Commercial LiCoO2 has been modified with LaF3 as a new coating material. The surface modified materials were characterized by X-ray diffraction (XRD), transmission electronic microscopy (TEM), field emission scanning electron microscopy (FE-SEM), auger electron spectroscopy (AES) and galvanostatic charge–discharge cycling. The LaF3-coated LiCoO2 had an initial discharge specific capacity of 177.4 mAh g−1 within the potential ranges 2.75–4.5 V (vs. Li/Li+), and showed a good capacity retention of 90.9% after 50 cycles. It was found that the overcharge tolerance of the coated cathode was significantly better than that of the pristine LiCoO2 under the same conditions – the capacity retention of the pristine LiCoO2 was 62.3% after 50 cycles. The improvement could be attributed to the LaF3 coating layer that hinders interaction between LiCoO2 and electrolyte and stabilizes the structure of LiCoO2. Moreover, DSC showed that the coated LiCoO2 had a higher thermal stability than the pristine LiCoO2.  相似文献   

6.
《Ceramics International》2019,45(12):14829-14841
In the present work, a new class of anode material for high energy applications of Li-ion battery is prepared by easy and large-scale producible process. Herein, the nanocomposite of MnO and reduced graphene oxide (rGO) is prepared by anchoring MnO nanoparticles into 3D matrix of rGO hydrogel followed by annealing process. The composite which has homogeneous distribution of MnO particles on conducting rGO layers demonstrated superior electrochemical performance such as high reversible capacity, stable cycle life and better rate capability. It has shown initial discharge capacity of 2358 mAh g−1 and retained 570 mAh g−1 after 100 cycles as compared to pristine MnO which shown initial discharge capacity of 820 mAh g−1 and retained only 45 mAh g−1 after 100 cycles. The retained capacity of new MnO/rGO anode is much higher than the theoretical capacity of conventional graphite anode. Moreover, the MnO/rGO nanocomposite shows six times higher Li+ ion diffusion of 4.18 × 10−12 cm2 s−1 as compared to 6.84 × 10−13 cm2 s−1 of MnO. In addition, the study provides insight of charge-discharge process, which conducted in initial, discharge and charge states of pristine MnO and MnO/rGO composite using ex-situ X-ray diffraction and X-ray photon spectroscopy techniques.  相似文献   

7.
《Ceramics International》2022,48(3):3397-3403
The high-Ni layered metal oxide, LiNi0.8Co0.1Mn0.1O2 (LNCM811), has received widespread attention in the energy field because of its high specific capacity, but its large-scale applications are hindered due to severe capacity fading. Herein, a uniform and thin Li2O–B2O3–LiBr-glass (LBBrO-glass) coating was deposited on LNCM811 by a liquid-phase coating and thermal treatment method. The experimental results suggested that the LBBrO-glass coating acted as a protective layer that inhibited transition metal dissolution and side reactions, which helped improve the electrochemical properties of LNCM811. Remarkably, after 200 cycles, the 2 wt% coating (LBBrO@LNCM-2) delivered a superior capacity retention of 88.9%, while only 71.8% was obtained for the pristine material (LNCM811). The discharge capacity of LBBrO@LNCM-2 was 163.5 mAh g?1 at 5C, while it was only 139 mAh g?1 for the pristine material.  相似文献   

8.
《Ceramics International》2017,43(12):8819-8823
Bi2O3 is a promising sodium storage material due to its high gravimetric specific capacity. However, Bi2O3 possesses lower electrochemical performance due to its poor electrical conductivity and structural integrity during Na+ insertion/extraction process. Here, we prepared a carbon coated Bi2O3 nanocomposite by a redox reaction and a carbon coating process. In this nanocomposite, the carbon layer can avoid the direct contact between Bi2O3 and electrolyte, which inhibits the repeated formation and decomposition of solid electrolyte interface film. Additionally, the carbon layer can enhance the electrical conductivity of Bi2O3 and suppress its aggregation due to its volume change during charge and discharge process. In addition, nano-sized Bi2O3 can reduce the transport distance of Na+ and electron. The nanocomposite shows excellent cycling performance and rate capability as anode for sodium-ion batteries. A high capacity of 421 mAh g−1 can be maintained after 100 cycles at 1500 mA g−1 and 392 mAh g−1 can be shown at 3200 mAh g−1.  相似文献   

9.
Li-rich layered cathode material (Li1.2Ni0.13Co0.13Mn0.54O2) is subjected to severe irreversible oxygen evolution for the first cycle, barren rate performance, capacity fading and voltage decay despite the ultrahigh specific capacity over 250?mAh?g–1. In this paper, MoOx was grown on the surface of lithium-rich material (LLO) via in situ hydrolysis deposition to ameliorate these problems. The surface of LLO was successfully coated with an amorphous MoOx modification layer, and a spinel phase was induced on the interlayer between the bulk material and the cladding layer, which was characterized by XRD, SEM, XPS and TEM. The Li1.2Ni0.13Co0.13Mn0.54O2 modified with 3?wt% MoOx exhibits the excellent electrochemical performance. The material performs higher capacity retention of 85.8% with 224.2?mAh?g–1 compared with the pristine one which retains 75.1% with 187.4?mAh?g–1 after 100 cycles at 0.5?C (1?C?=?250?mA?g–1) and exhibits high rate performance of 192.0?mAh?g–1 at 5?C. These outstanding electrochemical properties are attributed to the presence of oxygen vacancies in the MoOx that can effectively accommodate the oxygen from the Li2MnO3 during the first cycle of activation and promote oxygen reversible redox process. The MoOx coating layer can also eliminate side reactions on the surface of the material and maintain the integrity of the oxygen array. Furthermore, the 3d orbitals of lower oxidation state Mo in MoOx extend and partially overlap to form wide t2g bands, combined with the spinel phase possessing fast Li+ diffusion channels, which can significantly reduce the Li+ diffusion energy barrier and improve its rate performance.  相似文献   

10.
《Ceramics International》2019,45(10):13144-13149
Anatase TiO2 is widely used in lithium ion batteries (LIBs) due to its excellent safety and excellent structural stability. However, due to the poor ion and electron transport and low specific capacity (335 mAh g−1) of TiO2, its application in LIBs is severely limited. For the first time, we report a binder-free, carbon-coated TiO2@graphene hybrid by using copper foam as current collector (TG-CM) to enhance the ionic and electronic conductivity and increase the discharge specific capacity of the electrode material without adding conductive carbon (such as super P, etc.) and a binder (such as polyvinylidene fluoride (PVDF), etc.). When serving as an anode material for LIBs, TG-CM displays excellent electrochemical performance in the voltage range of 0.01–3.0 V. Moreover, the TG-CM hybrid delivers a high reversible discharge capacity of 687.8 mAh g−1 at 0.15 A g−1. The excellent electrochemical performance of the TG-CM hybrid is attributed to the increased lithium ion diffusion rate due to the introduction of graphene and amorphous carbon layer, and the increased contact area between the active material and electrolyte, and small resistance with copper foam as the current collector without an additional binder (PVDF) and conductivity carbon (super P).  相似文献   

11.
《Ceramics International》2020,46(8):11570-11576
This paper we use ZnCl2 to activates and reduces rice husks to produce SiOx@N-doped carbon core-shell nanocomposites with inner voids is a facile and effective strategy to improve the electrochemical performance. As an anode material for the lithium-ion batteries, the composites exhibit a high reversible capacity (1315 mAh g−1 after 100 cycles at 100 mA g−1) and long-term stability (584 mAh g−1 after 500 cycles at 500 mA g−1). Such outstanding cycling stability is attributed to the small size of the SiOx particles with inner voids and the carbon layer coating can guarantee good structural integrity for long cycle stability. As a cathode material for Li–S batteries, the composite displays a high capacity and good stability (675 mAh g−1 after 100 cycles at 0.1C). Its good performance and facile preparation will improve the utilization of rice husk waste.  相似文献   

12.
《Ceramics International》2019,45(16):19799-19807
Na2MnPO4F has drawn worldwide attention as cathode materials for sodium-ion batteries with great promise due to its high theoretical capacity (124 mAh g−1) and working voltage plateau (3.6 V). Unfortunately, its electrochemical performances are largely limited by the intrinsic low electron conductivity and sluggish diffusion of Na+. Herein, a reduced graphite oxide nanosheets and nano-carbon co-modified Na2MnPO4F nanocomposite is prepared via a simple hydrothermal method. And the composite possesses a three-dimensional “pellets-on-sheets” structure, in which core-shell structured nanoparticles (Na2MnPO4F nanoparticles coated by carbon coating layers) are uniformly anchored on the surface of well-dispersed reduced graphite oxide nanosheets. Such unique structure is favorable for fast Na+ and electron transports and supplies sufficient active sites for Na+ insertion. As the cathode of sodium-ion battery, the as-prepared dual carbon-modified Na2MnPO4F composite exhibits a super discharge capacity of 122 mAh g−1 at 0.05 C and high rate-performance (42 mAh g−1 at 2 C) as well as long cycle performance (77% capacity retention after 200 cycles at 0.1 C). Meanwhile, it presents two obvious potential platforms of about 3.7 V and 3.5 V during the charge and discharge process, respectively, revealing its potential applications in high energy density batteries.  相似文献   

13.
High nickel cathode material LiNi0.85Co0.10Al0.05O2 (NCA) has attracted public attention because of its high energy density and low cost in production, but the material also faces the problem of rapid capacity decay due to the phase transition upon redox process. In this study, the co-modification with Na and Nb cations is employed to stabilize the lattice and promote the electrochemical behavior of the NCA material upon the application at 4.5 V. X-ray diffraction (XRD) investigations show that the co-modification of Na and Nb in the lattice reduces the disordering of the lattice and suppresses the volume change during the redox process, thereby increasing the specific capacity and the cyclic performance for the NCA material upon 4.5 V application. The Co-doped sample presents a specific capacity of 212.5 mAh/g when cycled 0.1 C, together with a capacity retention of 94.3% at 0.5 C after 100 cycles. This shows an obvious promotion when compared to that of undoped one (208.7 mAh/g and 78.2%). Furthermore, at a current density of 5 C, the Co-doped sample displays a high specific capacity of 152.2 mAh/g, while the value for the pristine NCA is only 129 mAh/g. Such improvement in rate performance can be attributed to the increased diffusion coefficient (from 7.57 × 10?13 to 3.27 × 10?12 cm2 s?1) due to the expanded space of lithium slab after co-doping of Na and Nb. The Na–Nb co-doping approach in this report offers a simple route to provide cathode materials with improved cyclability and enhanced rate behavior, demonstrating high potential for commercial application.  相似文献   

14.
《Ceramics International》2020,46(14):22606-22618
This study aimed to prepare a composite coating material comprising a solid ionic conductor of lithium aluminum titanium phosphate (Li1.4Al0.4Ti1.6(PO4)3, LATP) and porous carbon through a sol-gel method. LiNi0.8Co0.1Mn0.1O2 (LNCM811) cathode material with dual-functional composite conductors (i.e., LATP@porous carbon), denoted as LATP-PC, was prepared. The dry-coating method, also called the “mechanical-fusion alloy route,” was used to modify Ni-rich LNCM811 cathode materials. X-ray diffraction (XRD), micro-Raman spectroscopy, and X-ray photoelectron spectroscopy confirmed that the LATP ionic conductor generated herein was uniformly deposited on 3D porous carbon and served as a dual-functional composite coating on LNCM811. Furthermore, the capacity retention of LATP-PC@LNCM811 was approximately 85.57% and 80.86% after 100 cycles at −20 °C and 25 °C, respectively. By contrast, pristine LNCM811 had the capacity retention of 78% and 74.96% at −20 °C and 25 °C, respectively. Furthermore, the high-rate capability of the LATP-PC@LNCM811 material was markedly enhanced to 169.81 mAh g−1 at 10C relative to that of pristine LNCM811, which was approximately 137.67 mAh g−1. The electrochemical performance of LNCM811 was enhanced by the uniform dual-conductive composite coating. The results of the study indicate that the LATP-PC@LNCM811 composite material developed herein is a potentially promising material for future high-energy Li-ion batteries.  相似文献   

15.
Electrochemical properties of mixed titanium-niobium oxide TiNb2O7 (TNO) synthesized via vacuum annealing as high potential anode material for lithium-ion batteries were investigated. Crystal structure, size, and morphology are nearly independent of the annealing atmosphere for starting materials but the color of vacuum-annealed TNO (TNO-V) is dark blue while white for the air-annealed one (TNO-A). X-ray photoelectron spectroscopy analysis also indicated that Ti4+ and Nb5+ in TNO are partially reduced into Ti3+ and Nb4+ due to the introduction of oxygen vacancy. Electronic conductivity for TNO-V was around 10−3 S cm−1 at room temperature and much higher than that for TNO-A (=10−11 S cm−1). In electrochemical testing, both TNO-A and TNO-V electrodes showed reversible capacity of 260-270 mAh g−1 at low current density of 0.5 mA cm−2, while at higher current density of 5.0 mA cm−2, TNO-V electrode retained higher reversible capacity of 140 mAh g−1 than that for TNO-A electrode (=80 mAh g−1). The enhancement of intrinsic electronic conductivity greatly contributes to improve the rate performance of TNO.  相似文献   

16.
《Ceramics International》2019,45(10):13219-13224
Hollow graphene spheres are successfully prepared and employed as the separator coating materials for lithium-sulfur batteries. The hollow graphene spheres coated separator has been proven an efficient trap to adsorb and block polysulfide, greatly alleviating the shuttle effect. In the case of using elemental sulfur as cathode active material and the weight of the diaphragm is only increased by 10.3%, the lithium-sulfur battery with hollow graphene spheres coated separator delivers a high initial specific capacity of 1172.3 mAh g−1 at the current density of 0.2 C, and the discharge capacity remains at 829.6 mAh g−1 after 200 cycles with a capacity decay of 0.146% per cycle, showing excellent electrochemical performance.  相似文献   

17.
In this study, we have successfully coated the CeO2 nanoparticles (CeONPs) layer onto the surface of the Ni-rich layered LiNi0.7Co0.2Mn0.1O2 cathode materials by a wet chemical method, which can effectively improve the structural stability of electrode. The X-ray powder diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS) are used to determine the structure, morphology, elemental composition and electronic state of pristine and surface modified LiNi0.7Co0.2Mn0.1O2. The electrochemical testing indicates that the 0.3?mol% CeO2-coated LiNi0.7Co0.2Mn0.1O2 demonstrates excellent cycling capability and rate performance, the discharge specific capacity is 161.7?mA?h?g?1 with the capacity retention of 86.42% after 100 cycles at a current rate of 0.5?C, compared to 135.7?mA?h?g?1 and 70.64% for bare LiNi0.7Co0.2Mn0.1O2, respectively. Even at 5?C, the discharge specific capacity is still up to 137.1?mA?h?g?1 with the capacity retention of 69.0%, while the NCM only delivers 95.5?mA?h?g?1 with the capacity retention of 46.6%. The outstanding electrochemical performance is assigned to the excellent oxidation capacity of CeO2 which can oxidize Ni2+ to Ni3+ and Mn3+ to Mn4+ with the result that suppress the occurrence of Li+/Ni2+ mixing and phase transmission. Furthermore, CeO2 coating layer can protect the structure to avoid the occurrence of side reaction. The CeO2-coated composite with enhanced structural stability, cycling capability and rate performance is a promising cathode material candidate for lithium-ion battery.  相似文献   

18.
《Ceramics International》2017,43(12):8590-8595
To improve the electrochemical performance of silicon-based anode material, lithium fluoride (LiF) and pitch carbon were introduced to co-modify a silicon/graphite composite (SG), in which the graphite acts as a dispersion matrix. The pitch carbon helps to improve the electronic conductivity and lithium ion transport of the material. LiF is one of the main components of the solid electrolyte interphase (SEI) formed on the silicon surface, helping to tolerate the large volume changes of Si during lithiation/delithiation. The modified SG sample delivered a capacity of over 500 mA h g−1, whereas unmodified SG delivered a capacity of lower than 50 mAh g−1 after 100 cycles at 100 mA g−1. When performed at 4 A g−1, the reversible capacity of the modified SG was 346 mAh g−1, much higher than that of SG (only 37 mA h g−1). The enhanced cycling and rate properties of the modified SG can be attributed to the synergetic contribution of the pitch carbon and LiF which help accommodate the volume change, reduce the side reaction, and form a stable solid electrolyte interface layer.  相似文献   

19.
《Ceramics International》2019,45(15):18462-18470
Herein, porous NiMoO4@C nanowire is purposefully synthesized using oleic acid as carbon source, and further evaluated as high performance anode material for Li-ion batteries (LIBs). Compared with the pure NiMoO4, porous NiMoO4@C nanowire exhibits high reversible charge/discharge specific capacity, excellent cycle stability and preeminent rate capability. A stable reversible lithium storage capacity of 975 mAh g−1 can still be maintained after 100 cycles at 200 mA g−1. When the current density decreases back from 3000 mA g−1 to 100 mA g−1, a high discharge specific capacity of 884 mAh g−1 is recovered. The porous structure and carbon layers can enhance the electronic transmission and structural stability, shorten the path lengths for ion and electron transport, and provide a mechanical buffer space to accommodate the volume expansion/contraction during the repeated Li+ insertion/extraction processes. All the results highlight that the porous NiMoO4@C nanowire composite would be a promising candidate for high performance anode material of LIBs owing to its excellent electrochemical properties.  相似文献   

20.
《Ceramics International》2021,47(20):28634-28641
In this study, ZnIn2S4 (B-ZIS) and ZnIn2S4/C (S-ZIS) composites anode are synthesized using hydrothermal method and followed by ball-milling process. The initial discharge/charge capacities for bare ZnIn2S4 (B-ZIS) are 524 and 378 mAh g−1 under a current density of 1 A g−1, which suffers from gradually capacity fading. To improve its cycle stability, high-energy ball-milling process (HEBM) with carbon black is applied to fabricate S-ZIS spherical particles. The as-obtained composite anode exhibits enhanced electrochemical performances not only on cycle stability, but also reversible capacity. The discharge and charge capacity of S-ZIS approach to 823 and 679 mAh g−1 at the first cycle and retain 468 and 459 mAh g−1 after 500 cycles at the high current density of 1 A g−1. Furthermore, ex situ X-ray diffraction (XRD) and ex situ X-ray photoelectron spectroscopy (XPS) techniques are used to monitor the evaluation of crystal structure of B-ZIS during charge and discharge processes. The results indicate that the metallic Zn and In were observed at low potential voltage during sodiation process and successfully converted back to spinel phase at above 0.5 V. The presence of high reversibility nature of B-ZIS may leads to the superior cycling and excellent rate capability of S-ZIS which makes ZnIn2S4 a potential anode material of sodium ion batteries.  相似文献   

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