SOLID STATE IONICS
·
2024
·
IF 3
Jiatai Wang,Yan Wang,Shunli Hou,Geng Zhou,Yuanyuan Li,Xiaocen Yan,Changjuan Deng,Xiaoyi Hou,Jian Li
Lithium-ion batteries (LIBs) as energy storage devices have been booming recently to fill the demand for energy requirements. High‑nickel ternary cathode material LiNi 0.815 Co 0.15 Al 0.035 O 2 (NCA), extremely possible to be the next generation of cathode materials for applications due to its high energy density , low cost, and environmental friendliness. However, the rate capability and cycling stability of this cathode material is mediocre. In this work, NCA-based cathode materials have been modified by sodium (Na + ) doping through a high-temperature solid-state reaction, the results show that Na + -doping can effectively improve the electrochemical performance of NCA. Electrochemical test results show that Na + -doping improves Li + diffusion coefficient , inhibits NCA polarization, and reduces the charge transfer impedance. As-prepared 2%Na-NCA at the current density of 1.0C shows a discharge-specific capacity of 149.16 mAh/g and a retention rate of 96.49% after 100 cycles, but the retention rate of the Pure-NCA was (84.47%). Furthermore, 2% Na-NCA shows 121.07 mAh/g at 5.0C, with an increase of 27.05 mAh/g over the Pure-NCA (94.02 mAh/g). The results of the study showed that doping with sodium ions can effectively improve the rate capabilities and cycling stability of NCA.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2021
·Vol. 28
·期 2
·305-316
·
IF 2.232
Wang Hao-yang,Cheng Xue,Li Xiao-feng,Pan Ji-min,Hu Jun-hua
To probe the coupling effect of the electron and Li ion conductivities in Ni-rich layered materials (LiNi 0.8 Co 0.15 Al 0.05 O 2 , NCA), lithium lanthanum titanate (LLTO) nanofiber and carbon-coated LLTO fiber (LLTO@C) materials were introduced to polyvinylidene difluoride in a cathode. The enhancement of the conductivity was indicated by the suppressed impedance and polarization. At 1 and 5 C, the cathodes with coupling conductive paths had a more stable cycling performance. The coupling mechanism was analyzed based on the chemical state and structure evolution of NCA after cycling for 200 cycles at 5 C. In the pristine cathode, the propagation of lattice damaged regions, which consist of high-density edge-dislocation walls, destroyed the bulk integrity of NCA. In addition, the formation of a rock-salt phase on the surface of NCA caused a capacity loss. In contrast, in the LLTO@C modified cathode, although the formation of dislocation-driven atomic lattice broken regions and cation mixing occurred, they were limited to a scale of several atoms, which retarded the generation of the rock-salt phase and resulted in a pre-eminent capacity retention. Only NiO phase “pitting” occurred. A mechanism based on the synergistic transport of Li ions and electrons was proposed.
研究领域:
材料科学
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电化学
·
能源存储技术
✓ 已验证
DOI
高影响因子
IONICS
·
2021
·Vol. 28
·期 2
·767-777
·
IF 2.817
Zang Guojing,He Min,Liao Youhao,Li Minsui,Hong Mingyao,Li Weishan
To improve the comprehensive performance of fibrous membrane based on poly(methyl vinyl ether-alt-maleic anhydride) P(MVE-MA)- and poly(vinylidene fluoride-co-hexafluoropropylene) P(VdF-HFP)-blended copolymers, a small amount of nano-Al 2 O 3 was doped by electrospinning technique to apply for high-energy-density cathode material of nickel-rich LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) based Li-ion battery. The results indicated that the electrospinning membrane and corresponding gel polymer electrolyte (GPE) only doped with 3.0 wt.% nano-Al 2 O 3 presented the proper structure and delivered the best electrochemical characterization. Due to the uniform distribution of nanoparticles on the fibers with higher density, the specific surface area and porosity of the fiber membrane were increased, leading to the improved fracture stress of 172.0 MPa for the membrane and ionic conductivity of 2.1 × 10 −3 S cm −1 for the GPE at room temperature. Contributed from the proper pore structure and the enhanced interfacial stability, the capacity retention of 89.4% was achieved for the Li/GPE/NCA coin cell after 200 cycles in the voltage range of 3.0 V and 4.3 V under room temperature using the GPE doped with 3 wt.% Al 2 O 3 , compared with that of 63.6% for the GPE without nanoparticles. Similarly, the discharge capacity of the coin cell under 7 C rate (123.2 mAh g −1 ) maintained 65% of that at 0.3 C (189.4 mAh g −1 ), showing good rate performance of the developed GPE. Therefore, the significant improvement in electrochemical stability of the GPE achieved by doping a small number of nanoparticles provided a simple and feasible solution for the development of high-energy-density Li-ion batteries.
研究领域:
材料科学
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电化学
·
能源存储
✓ 已验证
DOI
高影响因子
Journal of Energy Chemistry
·
2016
·Vol. 26
·期 3
·481-487
·
IF 2.322
Zhen Zhang,Pengfei Zhou,Huanju Meng,Chengcheng Chen,Fangyi Cheng,Zhanliang Tao,Jun Chen
LiNi 0.915 Co 0.075 Al 0.01 O 2 (NCA) with Zr(OH) 4 coating is demonstrated as high performance cathode material for lithium ion batteries (LIBs). The coated materials are synthesized via a simple dry coating method of NCA with Zr(OH) 4 powders, and then characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). Experimental results show that amorphous Zr(OH) 4 powders have been successfully coated on the surface of spherical NCA particles, exhibiting improved electrochemical performance . 0.50 wt% Zr(OH) 4 coated NCA delivers a capacity of 197.6 mAh/g at the first cycle and 154.3 mAh/g after 100 cycles with a capacity retention of 78.1% at 1 C rate. In comparison, the pure NCA shows a capacity of 194.6 mAh/g at the first cycle and 142.5 mAh/g after 100 cycles with a capacity retention of 73.2% at 1 C rate. Electrochemical impedance spectroscopy (EIS) results show that the coated material exhibits a lower resistance, indicating that the coating layer can efficiently suppress transition metals dissolution and decrease the side reactions at the surface between the electrode and electrolyte. Therefore, surface coating with amorphous Zr(OH) 4 is a simple and useful method to enhance the electrochemical performance of NCA-based materials for the cathode of LIBs.
研究领域:
电化学
·
材料科学
·
能源存储
·
电池技术
·
无机非金属材料
·
固态化学
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2024
·
IF 5.5
Xueting Pei,Yonghui Chen,Yu Han,Dongyan Zhang,Yuan Ha,Zhimin Li,Yuan Wang
The LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) nickel-rich layered cathode material is widely used for Li-ion batteries because of its excellent structural stability and high specific capacity. However, the Li/Ni mixing effect and the generation of interfacial secondary reactions in NCA cathode materials reduce the electrochemical properties of Li-ion batteries. Herein, we report a series of vanadium (V)-doped NCA cathode (VNCA) materials with different amounts of poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) polymers in-situ coated on the surface using a liquid-phase method. The introduction of PEDOT:PSS coating not only improves the conductivity of NCA cathode materials but also protects the surface of cathode materials from cracking during the cycle. Electrochemical results show that the PEDOT:PSS (2 wt%) coating possesses high capacity retention rate (83.58%) after 200 cycles at 1 C, which is better than that of the sample without coating (66.7%). The PEDOT:PSS (2 wt%) coated cathode materials also display superior rate performance to VNCA at high magnification. This work provides new methods and theoretical guidance for the development of efficient ternary cathode materials for Li-ion batteries.
✓ 已验证
DOI
高影响因子
SOLID STATE IONICS
·
2015
·
IF 2.561
Jingyun Yin,Xiayin Yao,Gang Peng,Jing Yang,Zhen Huang,Deng Liu,Yicheng Tao,Xiaoxiong Xu
The effect of solid electrolytes , i.e. Li 10 GeP 2 S 12 and Li 3.25 Ge 0.25 P 0.75 S 4 , on the rate and low temperature performances of LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) cathode in all solid state lithium batteries is investigated. The ionic conductivities for the synthesized Li 10 GeP 2 S 12 and Li 3.25 Ge 0.25 P 0.75 S 4 at room temperature (RT) are 8.27 × 10 − 3 and 2.03 × 10 − 3 S cm − 1 , respectively. These solid electrolytes are demonstrated as electrolytes for all solid state lithium batteries containing NCA cathode for the first time. The results show that Li 10 GeP 2 S 12 based battery exhibits superior rate performance (72.3 mAh g − 1 at 1 C, RT), cycling stability (capacity retention of 87.1% after 30 cycles at 0.1 C, RT) and low temperature performance (79.2 mAh g − 1 at 0.1 C and − 10 °C), which can be ascribed to its higher ionic conductivity and lower interfacial resistance between Li 10 GeP 2 S 12 and NCA cathode. It is indicated that all solid state lithium batteries with NCA cathode and Li 10 GeP 2 S 12 solid electrolyte can realize its potential application in high power and low temperature conditions.
研究领域:
材料科学
·
电化学
·
能源存储
·
固态离子学
·
电池技术
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2019
·
IF 5.383
Chao Chen,Ming Xu,Kai Zhang,Hao An,Gang Zhang,Bo Hong,Jie Li,Yanqing Lai
The Ni-rich layered oxide (NLO) cathode materials play a key role in developing high-energy-density lithium ion battery (LIB) for wide scale deployment of clean transportation technologies. However, surface reconstruction from a layered structure to a mixed spinel/rock-salt structure during charge/discharge cycles is related to the severe voltage decay and capacity fading of the stoichiometric NLO cathode materials, thus thwarting the practical implementation. Herein, we report a heterostructured NLO cathode that tackles the structural degradation and related voltage decay problems. The efficient internal “incore” volumetric heating by direct coupling of microwave energy induces formation of Ni, Co-rich core and Al-rich shell. As a result of the encapsulation of the atomically ordered NiAl 2 O 4 after heat treatment, the solid/electrolyte interphase and surface structure of NLO cathode remains stable. By applying this NiAl 2 O 4 /NLO heterostructured material as a cathode, we demonstrate its robustness in suppressing the voltage decay (0.8% after 100 cycles) during high-voltage cell operation. Rather than the typical modifications, our work explores a more efficient structure engineering process for applications in nano-/micro-manufacturing transition-metal based electrode materials and sheds light on developing high-performance LIB in the near future.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2019
·Vol. 15
·期 50
·1904854
·
IF 10.856
Junchao Zheng,Zhuo Yang,Alvin Dai,Linbo Tang,Hanxin Wei,Yunjiao Li,Zhenjiang He,Jun Lu
Although the high energy density and environmental benignancy of LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) holds promise for use as cathode material in Li-ion batteries, present low rate capabilities, and fast capacity fade limit its broad commercial applications. Here, it is reported that surface modification of NCA cathode ( R-3m ) with 5 nm-thick nanopillar layers and Fm-3m structures significantly improves electrode structure, morphology, and electrochemical performance. The formation of nanopillar layers increases cycling and working voltage stability of NCA by shielding the host material from hydrofluoric acid and improves structural stability with the electrolyte. The modified NCA cathode exhibits an enhanced 89% capacity retention at a rate of 1 C over that of pristine NCA (75.2%) after 150 cycles and effectively suppresses working voltage fade (a drop of 0.025 V after 300 cycles) during repeated charge–discharge cycles. In addition, the diffusion barrier of Li ions in NCA crystals at 0.80 V is noticeably smaller than that of Li ions in pristine NCA (0.87 eV). These findings demonstrate that this unique surface structure design considerably enhances cycle and rate performance of NCA, which has potential applications in other Ni-rich layered cathode materials.
研究领域:
材料科学
·
电化学
·
能源存储
·
锂离子电池
·
纳米材料
✓ 已验证
DOI
高影响因子
Nanoscale
·
2025
·Vol. 17
·期 27
·16515-16522
·
IF 5.1
Zhengwei Li,Zixuan Fang,Jiajun Zhu,Wenxi Yang,Yubing Guo,Fan Wang,Jiyang Li,Mengqiang Wu
NCA (LiNixCoyAl1−x−yO2, x ≥ 0.8) cathode materials have become some of the leading candidates for lithium-ion batteries due to their superior specific discharge capacity and more cost-effective production. Yet, NCA materials are facing significant challenges such as surface reconstruction and micro-cracks, which adversely impact their electrochemical performance and practical application. Herein, a simple doping modification strategy using high-valence Mo6+ cations is proposed to address these issues. The experimental analysis results demonstrate the following: (1) the high-valence Mo6+ cations provide additional positive charge and reduce the migration barrier for Li+, thereby improving the Li+ transport kinetics of NCA; (2) Mo6+ doping not only refines the primary particle size, which compacts the stacking of particles, but also optimizes the microstructure of NCA, which prevents the development of micro-cracks and thus enhances the interfacial and bulk-phase stability of NCA; (3) acting as lattice pillars in the TM layers, the high-valence Mo6+ cations increase the thermodynamic barrier for Ni2+ migration from TM sites to lithium sites as well as strengthen the binding with oxygen atoms, thereby suppressing surface reconstruction and oxygen release. Based on the results of electrochemical testing, the prepared Li(Ni0.80Co0.15Al0.05)0.995Mo0.005O2 (NCAM-1) demonstrates a remarkable capacity retention rate of 89.3% after 100 cycles within the voltage range of 3.0–4.3 V and at a rate of 1C, which is significantly higher than the 79.1% retention observed for Li(Ni0.80Co0.15Al0.05)O2 (NCA). Additionally, NCAM-1 delivers a specific discharge capacity of 153.5 mA h g−1 at a high rate of 10C, which is substantially elevated compared to that of NCA (113.5 mA h g−1).
研究领域:
电化学
·
材料科学
·
能源存储
·
固态化学
·
电池技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Xiaoya Gao,Zhimin Li,Honglin Yan,Dongyan Zhang,Yuan Wang,Yuan Ha
Ni-rich layered LiNi 0.80 Co 0.15 Al 0.05 O 2 (NCA) cathode materials have attracted extensive attention in power lithium ion batteries on account of their high specific capacities and low voltage delay. However, they still suffer from inferior cycling stability, especially operating at a high cutoff voltage. In this paper, a surface modification strategy was proposed by utilizing Al(PO 3 ) 3 as a coating material to enhance the cycling performance of NCA in 2.7–4.6 V (vs. Li/Li + ). The surface modification effects of Al 3+ lattice doping and Al(PO 3 ) 3 coating were verified to be well achieved. In particular, besides the functions in stabilizing surface crystal structure of the NCA and isolating the erosion from electrolyte, the Al(PO 3 ) 3 coating could eliminate the residual lithium on the NCA surface to in-situ generate the Li 3 PO 3 which was conductive to the rate performance. Accordingly, the Al(PO 3 ) 3 -modified NCA cathode delivered excellent cycling performance, of which the initial discharge capacity was 235.9 mAh . g −1 at high cutoff voltage of 4.6 V, with a capacity retention of 71.6% after 100 cycles at 1 C. This work demonstrates the feasibility of surface modification on NCA via the phosphate coating with multiple functions, and provides an efficient approach to improve the cycling stability of Ni-rich layered cathode materials at higher cutoff voltage.
研究领域:
材料科学
·
电化学
·
锂离子电池
·
能源存储
·
表面工程
·
固态化学
✓ 已验证
DOI
高影响因子
BIOMACROMOLECULES
·
2024
·
IF 5.5
Xiao Sun,Aoting Li,Ning Li,Guonan Ji,Ziyuan Song
Heteropolypeptides bearing two or more functional side chains are promising polymeric materials for various biomedical applications. However, conventional preparation of heteropolypeptides relies on the synthesis and purification of each N-carboxyanhydride (NCA) monomer in a separate manner, which substantially increases the time and cost. Herein, we report the facile preparation of heteropolypeptides with up to 86% yield within several hours, which are obtained from a mixture of crude NCA monomers. The combination of n-hexane precipitation and biphasic segregation effectively removed >90% impurities from crude NCA mixtures, allowing for the successful polymerization process. Various heteropolypeptides with monomodal distribution and narrow dispersity were efficiently prepared, whose compositions were predetermined by the feeding ratios of amino acids. We believe that this work significantly simplifies the preparation of various heteropolypeptides, boosting the downstream studies of these promising materials.
研究领域:
高分子科学
·
材料科学
·
生物技术
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
EUROPEAN POLYMER JOURNAL
·
2022
·
IF 5.546
Feiyi Zhang,Lanlan Yu,Zhun Deng,Shuli Liu,Chenxuan Wang,Lei Liu
A variety of natural proteins have shown anti-adhesive functionality against the non-specific adsorption by proteins and bacteria. A deep understanding of the contribution of amino acid composition to the antifouling performance of a natural protein is crucial for engineering a protein-based coating layer. Herein, we synthesized five types of homo poly(amino acid)s via the ring-opening polymerization of α-amino acid N -carboxy anhydride (NCA) to include exclusively one type of amino acid from lysine (K), glutamic acid (E), tyrosine (Y), alanine (A), and phenylalanine (F). Homo poly(amino acid)s were covalently immobilized on the surfaces of quartz and polyurethane (PU), respectively. The amino acid composition effects on the wetting and anti-bacterial adhesion of a homo poly(amino acid) coating layer were evaluated. We found that the wettability of homo poly(amino acid) coating layers exhibited a dependence on the intrinsic properties of amino acid side-chain, such as the hydration free energy and dipole moment of side-chain. The activity of a homo poly(amino acid) coating layer against bacterial adsorption was found to be independent of the wetting property of the amino acid side-chain. Our findings are different from the conventional opinion that the hydration property of a material surface coating layer correlates to its anti-bacterial functionality, emphasizing the complexity of the amino acid composition contribution to the activity against the non-specific adsorption of bacteria for a protein-mimicking system.
研究领域:
材料科学
·
生物材料
·
生物物理学
·
高分子化学
·
微生物学
✓ 已验证
DOI
高影响因子