Nanomaterials
·
2021
·Vol. 11
·期 12
·3393
·
IF 5.076
Shasha Qu,Wenbin Wu,Yunfan Wu,Yanping Zhuang,Jie Lin,Laisen Wang,Qiulong Wei,Qingshui Xie,Dong-Liang Peng
Lithium cobalt oxide (LCO) is the most widely used cathode materials in electronic devices due to the high working potential and dense tap density, but the performance is limited by the unstable interfaces at high potential. Herein, LiF thin film is sputtered on the surface of LCO electrodes for enhancing the electrochemical performance and reducing the voltage polarization. The polarization components are discussed and quantified by analyzing the relationship between electrochemical polarization and charger transfer resistance, as well as that between concentration polarization and Li-ion diffusion coefficients. In addition, the decreased charge transfer resistance, increased lithium-ion diffusion coefficients, and stabilized crystal structure of LiF-coated LCO are confirmed by various electrochemical tests and in-situ XRD experiments. Compared to that of pristine LCO, the capacity and cycling performance of LiF-coated LCO is improved, and the overpotential is reduced upon cycling. This work provides reference for quantifying the various polarization components, and the strategy of coating LiF film could be applied in developing other analogous cathode materials.Keywords:voltage polarization;lithium cobalt oxide;lithium fluoride;lithium-ion battery
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
ELECTROCHIMICA ACTA
·
2024
·
IF 5.5
Di Zhang,Pengfei Lv,Wei Qin,Yuanhua He
Lithium-metal anodes have attracted widespread attention owing to their high specific capacity. However, they still suffer from poor stability under high-rate cycling and safety issues, which are mainly induced by the significant growth of Li dendrites and the collapse of the solid electrolyte interphase during extended cycling. Effective protective coatings can withstand severe environmental corrosion during handling and cycling. In this study, we develop a convenient and controllable surface fluorination process to develop a dense and uniform ultrathin lithium fluoride (LiF) protective coating on the Li metal surface by vacuum evaporation . Advanced comprehensive analyses demonstrate that the 200 nm-thick LiF protective coating provides sufficient Li ion transmission channels for efficient transport. This reinforces the structural integrity to withstand volume changes during Li plating/stripping. The highly conformal LiF protective coating minimizes corrosion reactions with carbonate electrolytes and inhibits dendrite formation. Dendrite-free deposition is realized at a high current density of 3 mA cm – 2 . LiF@Li|LiFePO 4 full cells with a 200 nm LiF-coated Li anode exhibit up to 85.31% capacity retention over 600 cycles. Stable Li deposition is achieved for 1200 h under lean electrolyte conditions using a 200-nm LiF-coated Li anode. The developed protective coating shows excellent stabilizing effects on Li anodes and is expected to facilitate the optimization and practical application of Li metal anodes with sufficient interphase stability.
研究领域:
材料科学
·
电化学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry C
·
2023
·
IF 3.7
Huiyan Wu,Hailong Huang,Lingzhi Cao,Yiyang Liu,Jianxing Dai,Cuilan Ren,Min Ge,Yuan Qian,Shuxian Hu,Xiaobin Fu,Hongtao Liu
In this study, it was demonstrated that Na+ ionic doped crystals could be formed during the solidification of FLiNaK melts. The ionic adulterating behavior between Li+, Na+, and K+ ions was investigated in detail by using various 1D/2D solid-state NMR methods and theoretical calculations. 2D 19F–23Na and 19F–7Li HETCOR NMR showed that the Na+ ions could be doped into LiF and KF crystals to generate new adulterating phases. Furthermore, the doped ionic Na+ ions exhibited different dynamics in LiF and KF crystals, which is correlated to the bonding length of the lattice and the Na–F coordinated interactions. This study provides more insights into the ionic doped crystal phase formation in such simple alkali metal fluorides, which may be of greater significance in the application as optical devices.
研究领域:
材料科学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
Small
·
2025
·
IF 12.1
Jiabin Fang,Kang Wu,Lijun Qin,Jianguo Li,Wangle Zhang,Ting Gong,Hao Feng
Silicon anodes lose energy density during cycling due to baneful volume expansions and unfavorable interfacial rearrangements. In this work, silicon active materials are synthesized upon carbon black (CB@Si) using alternating pulses of SiCl4 and Si 2 H 6 by H/Cl exchange mechanism via atomic layer deposition. The loading and thickness of the deposited silicon material can be precisely tuned by changing the deposition cycle. 13.6 nm is demonstrated as the optimal thickness of the silicon layer based on the trade-off between capacity and stability. Next, a nanoporous fluorinated lithicone (LiFHQ) is controllably deposited onto CB@Si by molecular layer deposition. The pores in LiFHQ act as a buffer layer to relieve the silicon bulk from severe deformation by squeezing or ripping of pores, while the rich F groups in LiFHQ helps to construct a robust LiF-rich natural solid electrolyte interphase (nSEI)/LiFHQ hybrid skin. Molecular dynamics (MD) calculations verify that these pores allow a faster Li + permeation kinetics compared to a dense AlFHQ layer. The anode exhibits an impressive capacity retention of 70.2% at 2 A g −1 after 1000 cycles. This work demonstrates the advantages of atomic/molecular layer deposition strategies to synthesize the bulk and surface configurations of silicon anodes with high energy densities.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NATURE
·
2025
·Vol. 646
·期 8083
·102-107
·
IF 48.5
Liu Xiangsi,Li Shuyang,Yuan Chen,Zheng Bizhu,Cheng Gangya,Chen Yufan,Lu Xingyu,Gu Danyu,Lv Baijiang,Li Hao,Yan Zihan,Qian Hui,Zhu Yizhou,Sun Dalin,Song Yun,Xiang Yuxuan
The electrolyte–electrode interface serves as the foundation for a myriad of chemical and physical processes. In battery chemistry, the formation of a well-known solid–electrolyte interphase (SEI) plays a pivotal role in ensuring the reversible operations of rechargeable lithium-ion batteries (LIBs) 1 , 2 . However, characterizing the precise chemical composition of the low crystallinity and highly sensitive SEI presents a formidable challenge 3 . Here, taking lithium fluoride (LiF)—a widely studied and considered crucial SEI component 4 , 5 , 6 , 7 —as an example, we use 19 F solid-state nuclear magnetic resonance (NMR) and identify that LiF formed in SEI (LiF SEI ) has fruitful spectroscopy features that originated from the formation of limited LiF–LiH solid solutions: H-rich phase (LiH 1 − y F y ) and F-rich phase (LiF 1 − x H x ), which is further validated by 6 Li isotope NMR, synchrotron X-ray diffraction and cryo-electron microscopy (cryo-EM). By characterizing SEI formed in various electrolytes, we confirm the dominance of LiH 1 − y F y in high-coulombic-efficiency electrolyte, which can be rationalized by the fact that LiF–LiH solid solution shows improved ionic conductivity over LiF. As a proof of concept, we demonstrate that LiH 1− y F y -rich coating layer presents obvious advantages compared with LiF-rich coating layer in lithium-metal batteries. This revised understanding of the heterogeneous nature of SEI components would provide new insights for electrode–electrolyte interface design.
研究领域:
电化学
·
材料科学
·
能源化学
·
固体化学
·
电池技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 36
·2303020
·
IF 19
Yi Sun,Kuanxin Zhang,Run Chai,Yueda Wang,Xianhong Rui,Kang Wang,Huaxia Deng,Hongfa Xiang
Considered the promising anode material for next-generation high-energy lithium-ion batteries, SiO x has been slow to commercialize due to its low initial Coulombic efficiency (ICE) and unstable solid electrolyte interface (SEI) layer, which leads to reduced full-cell energy density, short cycling lives, and poor rate performance. Herein, a novel strategy is proposed to in situ construct an artificial hybrid SEI layer consisting of LiF and Li 3 Sb on a prelithiated SiO x anode via spontaneous chemical reaction with SbF 3 . In addition to the increasing ICE (94.5%), the preformed artificial SEI layer with long-term cycle stability and enhanced Li + transport capability enables a remarkable improvement in capacity retention and rate capability for modified SiO x . Furthermore, the full cell using Li(Ni 0.8 Co 0.1 Mn 0.1 )O 2 and a pre-treated anode exhibits high ICE (86.0%) and capacity retention (86.6%) after 100 cycles at 0.5 C. This study provides a fresh insight into how to obtain stable interface on a prelithiated SiO x anode for high energy and long lifespan lithium-ion batteries.
研究领域:
电化学
·
材料科学
·
能源存储
·
锂离子电池
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界面化学
·
纳米材料
✓ 已验证
DOI
高影响因子
IONICS
·
2024
·Vol. 30
·期 8
·4479-4486
·
IF 2.4
Tang Anping,Chen Juedong,Xu Guorong,Song Haishen,Wang Jinglun,Chen Hezhang
Non-intercalation cathode materials based on nanocomposites of lithium fluoride and Li-free transition metal compounds have drawn attention as materials for fabricating the cathode of lithium ion batteries owing to their high theoretical specific capacities and high redox voltages. In the present study, a nanocomposite of MnO-LiF was in situ synthesized by a quick annealing at 500 °C for just 5 min using a mixture of ammonium fluoride, manganese acetate, and lithium acetate as precursor. The synthesized composite is investigated by X-ray diffraction, scanning electron microscopy, nitrogen sorption, and charge-discharge measurements. As a lithium-ion battery cathode, it delivers respectively an initial discharge-specific capacity of 170 mAh g −1 and a discharge-specific capacity of 137 mAh g −1 in the 50th cycle at a current rate of C/20, which is equivalent to a moderate capacity retention rate of 80.6%. The novel synthesis approach proposed offers access to electrochemically active composites of lithium fluoride and Li-free transition metal oxides.
研究领域:
材料科学
·
电化学
·
纳米复合材料
·
能源存储
·
锂离子电池
✓ 已验证
DOI
高影响因子
IONICS
·
2025
·Vol. 31
·期 9
·8961-8969
·
IF 2.6
Ning Liping,Sui Zhixing,Tang Anping,Liang Ziqin,Chen Hezhang,Song Haishen,Xu Guorong
Conversion reactions have made LiF-metal oxide (MO) composites with attractive specific capacities compelling candidates for the next generation of lithium-ion battery cathode materials. However, it is necessary for the high charge voltage (> 4.5 V) to drive the redox reaction of MOs and break a strong ionic bond between Li + and F − upon charge. It is a crucial way for decrease in the charge voltage to lower the activation energy barrier of the redox process between LiF and MOs. A novel conversion cathode LiF-V 2 O 3 system is proposed in this study. Unlike most of the previously reported LiF-MOs systems, the LiF-V 2 O 3 system can work at the lower charge cut off voltage of 4.3 V. It delivers a reversible specific capacity of 197 mAh g −1 at C/20 rate in the voltage range of 2–4.3 V. Cyclic voltammetry data suggest a dominant contribution of pseudocapacitance effect in the conversion reaction of the LiF-V 2 O 3 sample.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2025
·
IF 14.9
Jie Deng,Ningxin Chen,Sida Xie,Shan Liu,Zichan Yuan,Shuaiming He,Shi Chen,Zhaohui Wang
Cellulose, the most abundant and renewable biopolymer, offers a sustainable and cost-effective solution for regulating lithium electrodeposition toward safer lithium metal batteries, thanks to its high nanofibrous structure and intrinsic lithiophilic property. In this work, we introduce interface-engineered cellulose-based separators by converting intrinsic hydroxyl groups on cellulose nanofibers (CNFs) to nitrogen functionalities through a trace conducting polymer coating. Both experimental and theoretical results reveal that the nitrogen moieties disrupt the compact hydrogen bond network within hydroxyl cellulose, enabling multiple nitrogen-lithium interactions that enhance lithium ion transport. In addition to an extraordinary Li + transference number of 0.86 and a high ionic conductivity of 1.1 mS cm −1 , the nitrogen-functionalized CNF contributes to a uniform electric field and Li + concentration distribution across the lithium metal surface. This facilitates the formation of a LiF-rich solid electrolyte interface and suppresses Li dendrite growth. Consequently, Li||Li cells demonstrate stable plating/stripping cycles for approximately 3000 h at a current density of 1 mA cm −2 with a fixed capacity of 1 mAh cm −2 , while maintaining a low overpotential of 15 mV. Our work provides valuable insights into the surface functionalization of natural biomass for advancing sustainable energy storage technologies.
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2023
·
IF 6.6
Mingyang Li,Fangyuan Bai,Qi Yao,Hecheng Wang,Peng Li
Lithium cobalt oxide (LCO), as a popular commercial material, can release higher capacity by increasing the charging voltage. However, deep delithiation leads to the dissolution of elements and structural disorder. Meanwhile, high-temperature performance is still in urgent need to be improved in practical application. Here, we use LiNO 3 , NaF and H 3 BO 3 as raw materials to construct the outer LiF-rich layer and the inner B, F gradient doped hierarchical nanostructures through stirring and calcination . The electrochemically stable LiF-rich surface helps to form a favorable cathode electrolyte interphase (CEI) layer to prevent electrolyte penetration. The gradient doping of B and F in the subsurface region increases the stability of the lattice at high temperature and high potential. The unique structure enables treated LCO to demonstrate stable cycling under high voltage (4.6 V) with a capacity retention of 93.2% after 800 cycles and displayed 95.2% retention for 100 cycles under high temperature (45 °C). The postmortem analyses after long cycles prove the strategy of surface modification helps to protect the structure and reduce adverse reactions. This study provides a simple and extendable method for improving the cycling stability of cathodes at high temperature and high voltage.
研究领域:
材料科学
·
电化学
·
能源存储
·
锂离子电池
·
固态化学
·
纳米结构
✓ 已验证
DOI
高影响因子
Advanced Science
·
2022
·Vol. 9
·期 11
·2104841
·
IF 17.521
Shulan Mao,Zeyu Shen,Weidong Zhang,Qian Wu,Zhuoya Wang,Yingying Lu
The energy density of batteries with lithium cobalt oxide (LCO) can be maximized by increasing the cut-off voltage to approach the theoretical capacity limit. However, it is not realized in the practical applications due to the restricted cycle life caused by vulnerable cathode surface in deep delithiation state, where severe side reactions, oxygen/cobalt loss and structure degradation often happen. Here, an outside-in oriented nanostructure on LiCoO 2 crystals is fabricated. The outer electrochemically stable LiF and Li 2 CoTi 3 O 8 particles perform as physical barrier to prevent damage of both cathodes and electrolytes, while the inner F doping promote Li ions diffusivity and stabilize the lattice oxygen. With the spinel-like transition layer between them, a solid and complete lithium-ion transport channel generation along the lithium concentration gradient. Under the protection from this structure, the LiCoO 2 withstand the high voltage of 4.6 V and the LCO/graphite pouch full cell with high loading density exhibits 81.52% energy density retention after 135 cycles at 4.5 V.
研究领域:
材料科学
·
储能
·
电化学
✓ 已验证
DOI
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2025
·
IF 3.2
Zhangqi Li,Shizhuan Xu,Peng Wang,Jinzhao Zou,Jian Chen,Changqing Cao,Jin Lin
Although uranium trifluoride (UF 3 ) holds promise for applications in molten salt reactors, its high-temperature physicochemical properties in molten salt systems have yet to be thoroughly explored. In this study, the solubility and dissolution kinetics of UF 3 in molten 2LiF-BeF 2 (66–34 mol %, FLiBe) eutectic salt were investigated using the isothermal saturation method within the temperature range of 823 K to 973 K. High-purity UF 3 compacts (∼99.70 %) were synthesized via an optimized solid-phase reaction protocol and subsequent compacting. The UF 3 -saturated FLiBe molten salts were prepared by immerse dissolution of nickel mesh-wrapped UF 3 compacts and bulk uranium in the molten salt, eliminating the filtration step. Experimental findings showed that the dissolution equilibrium of UF 3 in the FLiBe salt was 120 h. The solubility of UF 3 exhibited a linear increase (R 2 > 0.99) from 4.16 wt. % to 12.60 wt. % as the elevation of temperature. Crystallographic analysis confirmed that the typical UF 3 phase was the only uranium-bearing phase throughout the dissolution process, while deconvolution X-ray photoelectron spectroscopy (XPS) verified the exclusive presence of the U 3+ species under all temperature conditions. Notably, the dissolution kinetics conformed to a mass transport control model.
研究领域:
核化学
·
材料科学
·
物理化学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）