JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2021
·Vol. 168
·期 3
·030501
·
IF 4.316
Liuyang Zhao,Huimin Xu,Hao Ru,Yueli Shi,Quanchao Zhuang,Yongli Cui,Zhicheng Ju,Yanhua Cui
Conversion-type lithium–metal fluoride batteries with high energy density, are considered to be very promising candidates for the next generation of low-cost lithium-ion batteries. Unfortunately, metal fluoride cathodes generally suffer from poor conductivity, sluggish reaction kinetics, and irreversible structural changes. Reducing particle size to nanoscale is an effective way to solve the large volume change and poor electronic conductivity of metal fluoride cathodes. In this study, a nano-control strategy was proposed, using n-propanol as an auxiliary solvent to achieve the conversion of micrometer-scale FeF3·3H2O to nanoscale FeF3·0.33H2O. Meanwhile, the particle size and morphology of iron fluorides could be controlled by regulating the synthesis temperature. The distribution of relaxation times (DRT) was used to analyze the electrochemical impedance spectroscopy (EIS). FeF3·0.33H2O synthesized at 180 °C with lower resistance showed a high capacity of 200 mAh g−1 after 160 cycles with excellent rate performance and cycle stability.
研究领域:
材料科学
·
电化学
·
能源存储技术
✓ 已验证
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 45
·期 38
·18019-18024
·
IF 3.591
Jing Ding,Xiangyang Zhou,Chucheng Luo,Juan Yang,Jingjing Tang
FeF3·0.33H2O with a special one-dimension tunnel structure has been considered as a potential cathode material. However, the low electron conductivity of FeF3·0.33H2O prevents its practical application. FeF3·0.33H2O coupled with a carbon material is an effective method to solve the low electric conductivity of FeF3·0.33H2O. Hence, we apply a facile approach using the catalyzed pyrolysis of melamine and a fluorination–annealing process to synthesize the N-doped CNTs/FeF3·0.33H2O composite with a bamboo-like morphology. The as-prepared composite displays a good cycling performance with a reversible discharge capacity of 160.7 mA h g−1 at 40 mA g−1 after 100 cycles and a good rate performance, as well as a good electrochemical performance even at a relatively high mass loading. The good electrochemical properties can be mainly ascribed to the fact that N-doped CNTs play the role of a cross-linked conductive network to provide an electron-transport expressway in the active material. This simple catalyzed pyrolysis and fluorination–annealing approach provides a promising avenue for the application of iron fluoride as a cathode material.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
DOI
高影响因子
Nanoscale Research Letters
·
2019
·Vol. 14
·期 1
·1-11
·
IF 3.159
Lu Lu,Li Sheng,Li Jun,Lan Lifang,Lu Yan,Xu Shuaijun,Huang Si,Pan Chunyang,Zhao Fenghua
The FeF 3 ·0.33H 2 O cathode material can exhibit a high capacity and high energy density through transfer of multiple electrons in the conversion reaction and has attracted great attention from researchers. However, the low conductivity of FeF 3 ·0.33H 2 O greatly restricts its application. Generally, carbon nanotubes (CNTs) and graphene can be used as conductive networks to improve the conductivities of active materials. In this work, the FeF 3 ·0.33H 2 O cathode material was synthesized via a liquid-phase method, and the FeF 3 ·0.33H 2 O/CNT + graphene nanocomposite was successfully fabricated by introduction of CNTs and graphene conductive networks. The electrochemical results illustrate that FeF 3 ·0.33H 2 O/CNT + graphene nanocomposite delivers a high discharge capacity of 234.2 mAh g −1 in the voltage range of 1.8–4.5 V (vs. Li + /Li) at 0.1 C rate, exhibits a prominent cycling performance (193.1 mAh g −1 after 50 cycles at 0.2 C rate), and rate capability (140.4 mAh g −1 at 5 C rate). Therefore, the electronic conductivity and electrochemical performance of the FeF 3 ·0.33H 2 O cathode material modified with CNTs and graphene composite conductive network can be effectively improved.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
电池技术
✓ 已验证
DOI
高影响因子
Advanced Energy Materials
·
2023
·Vol. 13
·期 23
·2300706
·
IF 27.8
Jian Peng,Xue Wang,Hong Li,Liquan Chen,Fan Wu
Metal fluoride–lithium batteries with potentially high-energy densities are regarded as promising candidates for next-generation low-cost rechargeable batteries. However, liquid-electrolyte metal fluoride–lithium batteries suffer from sluggish reaction kinetics, high voltage hysteresis due to side reactions, poor rate capability, and rapid capacity drop during cycling. Moreover, the research on sulfide all-solid-state batteries (ASSBs) with metal fluoride cathode is still lacking. Herein, four kinds of iron fluoride materials are applied to the sulfide all-solid-state lithium battery system for the first time to investigate the best cathode and corresponding methods. Electrochemical tests showed the cycling performance at different current densities (0.1, 0.3, and 1 C) and rate performance of the four cathodes with the following rules: FeF 3 -HT > FeF 3 -RT > FeF 3 ·0.33H 2 O > FeF 3 ·3H 2 O. The reversible capacities of FeF 3 -HT AASB are 519.9 mAh g −1 after 120 cycles at 0.3C and still maintains 340.7 mAh g −1 after 400 cycles even at a high rate of 1 C. In addition, electro impedence spectroscopy and cyclic voltammetry tests of the above four cathodes show that different contents of crystal water, morphologies, and particle sizes have a great influence on the lithium storage mechanism of cathode. Moreover, the reason for the FeF 3 -HT cathode's superior specific capacity and rate performance compared with other cathodes at high current densities is revealed, according to cyclic voltammogram tests under different scan rates. The cause is that FeF 3 -HT has the highest proportion of the contribution capacity of the cathode surface control process. The above research opens up a new avenue for FeF 3 -HT, FeF 3 -RT, FeF 3 ·0.33H 2 O, and FeF 3 ·3H 2 O cathodes in sulfide ASSBs.
研究领域:
材料科学
·
能源存储
·
电池技术
·
电化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）