Surfaces and Interfaces
·
2024
·
IF 5.7
Fangfang Shang,Hengdao Quan,Xiaoxun Ma
In this study, 3-trifluoromethylpyrazole (TMPZ) was developed as a multifunctional electrolyte additive to enhance wettability between separator and electrolyte, CEI formation and remove HF to improve the performance of Li/NCM622 batteries by experiment and theoretical calculation. After 200 cycles at 30 °C, the discharge capacity retention of batteries at 1 C with 0.5 wt% TMPZ additive is remarkably enhanced from 68.3 % to 83.2 %. The enhanced electrochemical performance of the batteries by adding TMPZ additive is evaluated by the spectroscopic characterization and theoretical calculation. It is demonstrated that TMPZ can generate uniform and dense CEI film via ring-opening electrochemical polymerization of TMPZ on the NCM622 electrode surface. The CEI film helps to suppress the breakdown of LiPF 6 electrolyte and the leaching of transition metals, effectively avoiding harmful side reactions between the NCM622 electrode and the electrolyte. Furthermore, introducing TMPZ can enhance the wettability between separator and electrolyte, therefore providing more channels of Li + to accelerate reaction kinetics of batteries.
研究领域:
材料科学
·
电化学
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产品关联
DOI
高影响因子
RSC Advances
·
2023
·Vol. 13
·期 48
·33905-33910
·
IF 3.9
Kai Huang,Jinxia Zhou,Huili Yang,Tianzheng Xie,Tu Lan,Suichang Ong,Heng Jiang,Yibo Zeng,Hang Guo,Ying Zhang
The Ni-rich NCM622 is a promising cathode material for future high energy lithium ion batteries, but unstable electrochemical performance of NCM622 hinder its large scale commercial application. The cycling peformance of nickel-rich LiNi0.6Co0.2Mn0.2O2 (NCM622) cathode materials can be improved by surface coating. Here, a one-step approach based on TiF4 is used to successfully manufacture modified NCM622 cathode materials with a TiO2–LiF coating. The TiO2–LiF coated NCM622 preserves 79.7% capacity retention which is higher than the pure NCM622 (68.9%) at 1C after 200 cycles within 2.7–4.3 V. This material serves as the cathode for lithium-ion batteries (LIBs). The uniform TiO2–LiF coating layer can alleviate structural degradation brought on by unfavorable side reactions with the electrolyte has been validated. TiO2–LiF coated on NCM622 cathode materials can be modified easily by one-step approach.
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DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 19
·2212150
·
IF 19
Zhongsheng Wang,Chunlei Zhu,Jiandong Liu,Xinhong Hu,Yulu Yang,Shihan Qi,Huaping Wang,Daxiong Wu,Junda Huang,Pengbin He,Jianmin Ma
Tailoring inorganic components of cathode electrolyte interphase (CEI) and solid electrolyte interphase (SEI) is critical to improving the cycling performance of lithium metal batteries. However, it is challenging due to complicated electrolyte reactions on cathode/anode surfaces. Herein, the species and inorganic component content of the CEI/SEI is enriched with an objectively gradient distribution through employing pentafluorophenyl 4-nitrobenzenesulfonate (PFBNBS) as electrolyte additive guided by engineering bond order with functional groups. In addition, a catalytic effect of LiNi 0.6 Mn 0.2 Co 0.2 O 2 (NCM622) cathode is proposed on the decomposition of PFBNBS. PFBNBS with lower highest occupied molecular orbital can be preferentially oxidized on the NCM622 surface with the help of the catalytic effect to induce an inorganic-rich CEI for superior electrochemical performance at high voltage. Moreover, PFBNBS can be reduced on the Li surface due to its lower lowest unoccupied molecular orbital , increasing inorganic moieties in SEI for inhibiting Li dendrite generation. Thus, 4.5 V Li||NCM622 batteries with such electrolyte can retain 70.4% of initial capacity after 500 cycles at 0.2 C, which is attributed to the protective effect of the excellent CEI on NCM622 and the inhibitory effect of its derived CEI/SEI on continuous electrolyte decomposition.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Meiting Huang,Haoxuan Yu,Liang Chen,Haitao Yang,Zhihao Wang,Yifeng Li,Kechun Chen,Chenxi Xu,Liming Yang,Xubiao Luo
To face the large–scale retirement of lithium–ion batteries (LIBs), direct regeneration of spent NCM622 (LiNi 0.6 Co 0.2 Mn 0.2 O 2 ) cathode can effectively alleviate the current resource and environmental pressures. During the recycling process, the binder polyvinylidene fluoride (PVDF) inevitably becomes an inherent impurity in the active material. Whether the inherent impurity can assist the regeneration of spent NCM or not is becoming a focus of attentions. Hereby, a closed–loop direct regeneration strategy that transforms the inherent PVDF impurity into a F dopant is proposed, and a LiNO 3 –LiOH eutectic molten system is utilized to repair the elemental loss and structural defects in highly degraded NCM622 cathode while achieving F doping. It is found that the fluorine element is uniformly doped into both the surface and bulk phases of the whole material. The F–containing regenerated NCM cathode (R–NCM622–F) shows a stable layered structure with markedly suppressed lattice oxygen escape, as substantiated by the experimental analysis and theoretical calculation. As a result, the obtained R–NCM622–F exhibits a satisfactory repaired specific capacity of 169.6 mAh g −1 and excellent cycling stability, which retains 85.8 % of its initial capacity after 200 cycles. Meanwhile, it can deliver a considerable capacity of 120mAh g −1 even at a high rate of 5C. Clearly, our regeneration strategy obviates the necessity for intricate pretreatments, and instead employs the inherent PVDF impurity to achieve the direct regeneration process, thereby offering a promising avenue to the large–scale direct regeneration of layered cathodes.
研究领域:
材料科学
·
环境科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Yongshun Liang,Lang Xu,Ya Li,Jie Ding,Yiyao Li,Kaijiao Duan,Wei Bai,Junming Guo,Mingwu Xiang
Layered Ni-rich oxides LiNi x Co y Mn 1-x-y O 2 (x ≥ 0.6, x + y = 1) are considered the best promising cathode material for high-performance lithium-ion secondary batteries. However, the time-consuming and complicated preparation process of spherical precursors greatly increases the consumption of energy and time, whilst suffering the challenges of liquid waste and Li uniform distribution. Herein, a simple microwave liquid phase flameless combustion method with the advantages of time-saving and energy-conservation has been proposed to synthesize Ni-rich LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM 622 ). The NCM 622 powders with uniform element distribution are obtained by heating the liquid mixture of raw materials in a simple domestic microwave oven only for 5 minutes and without waste liquid production. Subsequently, the microwave-synthesized NCM 622 powders are further calcined in high-temperature with different temperatures and time in order to obtain the final products with high crystallinity and good electrochemical performances. As a result, the optimal NCM 622 cathode material calcined at 800 °C for 14 h exhibits excellent irregular polyhedral morphology and low degree of Li + /Ni + mixing, whilst displays high first discharge capacity of 179.1 mAh g −1 and 204.9 mAh g −1 with the capacity retention of 88.21 % and 81.36 % (100 cycles) in 3–4.3 V and 3–4.5 V (0.2 C), respectively.
研究领域:
材料科学
·
能源技术
✓ 已验证
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Jiale Fu,Daobin Mu,Borong Wu,Jiaying Bi,Xiaojiang Liu,Yiyuan Peng,Yiqing Li,Feng Wu
Developing high-voltage Li ion batteries (LIBs) is an important trend to meet the requirement of high energy density battery . However, high voltage will cause a series of problems harming the cycle performance of LIBs at the same time. This work is to investigate the effect of inorganic substance Li 2 SiO 3 on the electrochemical performance of LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) cathode at high cutoff voltage of 4.6 V. XRD result shows that the structure of NCM622 cathode material is not affected by mixing Li 2 SiO 3 . However, XPS and EIS tests indicate that Li 2 SiO 3 has an evident influence on suppressing the decomposition of LiPF 6 and carbonate solvents at high voltage, reducing interfacial solid film impedance and modifying electrode/electrolyte interface. In addition, Li 2 SiO 3 retards the transition metal dissolution by consuming HF. Therefore, it enhances the electrochemical properties of the NCM622 cathode significantly. The highest discharge capacity increases to 191.7 mA h g -1 by mixing Li 2 SiO 3 , compared with the value of 180 mA h g -1 in the case of NCM622 cathode. The NCM622 electrode mixed with Li 2 SiO 3 also exhibits a better capacity retention of 73.4% after 200 cycles and a high rate capability at 20C with the value of 89 mA h g -1 , in contrast with 62.2% and 31 mA h g -1 attained in the NCM622 cathode.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Ruijia Diao,G.P. Nayaka,Chengyi Zhu,Xiaohua Yu,Yannan Zhang,Ju Rong,Xiao Wang,Yingjie Zhang,Peng Dong,Mingyu Zhang,Xi Yang,Zhaolin Zhan
A facile hydrothermal method is successfully developed for the synthesis of CePO4 coated LiNi0.6Co0.2Mn0.2O2 (NCM 622) cathodes. The as-prepared samples are characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), electrochemical workstation, electrochemical impedance spectroscopy (EIS) and inductively coupled plasma emission spectrometry (ICP). Compared to the pristine NCM 622 cathode, the rate capacity and cyclic performance are significantly improved after coating. Even under a 10 C charge/discharge rate, the initial discharge capacity of the 3.0-NCM sample is up to 95.2 mAh . g -1 . Furthermore, the as- prepared 3.0-NCM sample exhibits excellent cyclic performance with 96.8% capacity retention at 1 C under 55 o C after 100 cycles, while the pure NCM 622 only delivers poor capacity retention of 71.4%. The above conclusions can be characterized that CePO4 coating layer can effectively avert the secondary reaction between electrolyte and cathode material. In addition, the CePO4 coating layer can significantly suppress the dissolution of cathodes in the electrolyte, which contributes to the excellent rate performance and cycle stability.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
Energy Storage Materials
·
2026
·
IF 19.3
Haoruo Xiao,Shuhan Wang,Kai Wan,Chenrui Zeng,Yang Zhang,Yan Huang,Chaozhu Shu,Zhenxing Liang
Direct regeneration of mixed cathode materials remains challenging due to the lack of feasible separation techniques and the compositional/structural heterogeneity of degraded components. This study proposes a mixed upcycling regeneration (MUR) strategy aimed at converting mixed spent layered oxide cathodes into refreshed cathode material with uniform composition and consistent structure. By constructing a LiOH-Ni(OH) 2 -Na 2 SO 4 ternary eutectic-salt system, we successfully transform a mixture of spent polycrystalline LiNi 0.8 Co 0.1 Mn 0.1 O 2 (S-NCM811), LiNi 0.5 Co 0.2 Mn 0.3 O 2 (S-NCM523) and LiCoO 2 (S-LCO) into single-crystalline LiNi 0.6 Co 0.2 Mn 0.2 O 2 (MUR-NCM622). This strategy achieves compositional homogenization and precise transition-metal compensation of the regenerated product in the molten-salt medium, while leveraging Ostwald ripening to accomplish the structural transformation from polycrystalline to single-crystalline. Notably, the introduction of Ni(OH) 2 not only compensates for the nickel loss of the spent cathode during cycling but also significantly reduces cation disorder in the regenerated product, thereby synergistically enhancing both compositional integrity and structural ordering. The regenerated single-crystalline MUR-NCM622 demonstrates a significant advantage in electrochemical stability over commercial polycrystalline NCM622 (PC-NCM622). This work provides a viable technical route for efficient and high-value recycling of complex mixed cathodes.
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DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2019
·
IF 7.467
Shili Wang,Shimou Chen,Weiqun Gao,Lili Liu,Suojiang Zhang
In this paper, we propose a new electrolyte additive 3-Isocyanatopropyltriethoxysilane (IPTS) to improve the cycle stability and rate performance of Ni-Rich (LiNi 0·6 Co 0·2 Mn 0·2 O 2 ) cathode half-cell. Density function theory calculations suggest that IPTS has higher HOMO energy than solvent, which can decompose preferentially. Moreover, we confirm the oxidative decomposition by the linear scanning cyclic voltammetry , which can achieve stable at a cutoff voltage of 2.5–4.5 Vs. (Li/Li + ). The cyclic voltammetry curves at different scan rates indicate that the migration rate of lithium ions is higher in the cells with 0.5% additive than in the base electrolyte. After 150 cycles, the capacity retention rates in the base electrolyte and in the additive-containing electrolyte are 55.4% and 73.1%, respectively. X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy show that the additive is involved in film formation, and the obtained CEI film is very uniform and dense, which play a key role in stabilizing the electrolyte under high voltage.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2017
·
IF 4.798
Hao Wang,Daming Sun,Xiang Li,Wujie Ge,Bangwei Deng,Meizhen Qu,Gongchang Peng
Three kinds of functional organosilicons electrolyte additives, i. e. octamethylcyclotetrasiloxane (D4), octamethylcyclotetrasiloxane (OMCTS) and 2,4,6,8-tetramethyl-2,4,6,8-tetravinylcyclotetra- siloxane (ViD4), are firstly used to produce high-performance LiNi 0.6 Co 0.2 Mn 0.2 O 2 cathode for rechargeable Lithium-ion batteries (NCM622/Li half-cell) at a high potential. The electrochemical performance tests at 4.5 V suggest that ViD4 is the most promising electrolyte additive than its counterparts. Moreover, the prepared NCM622/Li half-cell with 0.5 wt.% ViD4 exhibits an improved energy density of 187.2 mAh g −1 and a good discharge capacity retention of 83.6% at 1C rate after 150 cycles at 4.5 V, which is relatively higher than that with D4 (81.3%), OMCTS (81.9%) and much better than the bare electrolyte (76.1%). The electrochemical characterizations, density functional theory calculation and surface analysis provide strong evidences that combined effects of the Si-O bond and vinyl functional group in ViD4 can promote the formation of a uniform cathode electrolyte interphase (CEI) film. Moreover, the ViD4-incorporated CEI film effectively enhances the interfacial stability between the NCM622 cathode and the electrolyte by suppressing the continuous decomposition of carbonate-based electrolyte and the exfoliation of these decomposition products. Hence, the ViD4-containing electrolyte shows a promising potential for the application in high energy density lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2021
·
IF 5.316
Wenqian Zhang,Li Xiao,Jiangfeng Zheng,Yuelian Zhong,Bo Shi,Han Chen,Haikuo Fu
The electrochemical properties and thermal stability of the LiNi 0.6 Co 0.2 Mn 0.2 O 2 (NCM622) material have been significantly improved by Nb 2 O 5 nanocoating. The electrochemical properties were researched systematically by various electrochemical tests, and the molar ratio of Nb 2 O 5 to NCM622 was evaluated as 0.5 mol%. Results showed that Nb 2 O 5 nanocoated sample exhibited good cyclic performance, whose capacity retention was 92.36%, whereas that of the bare NCM was only 87.59% after 200 cycles under 1C at 25 °C. In addition, the Nb 2 O 5 surface-coated sample exhibited a good discharge capacity of 164.05 mAh g −1 after 200 cycles under 1C at 60 °C. The result owing to the nano coating of Nb 2 O 5 , which greatly increased the thermal stability, thereby maintaining remarkable specific capacity even in high-temperature environments. The modified sample could maintain a relatively complete structure after cycling, whereas the bare sample had already collapsed. Based on the transmission electron microscopic images, the thickness of the coating layer was about 15 nm. The nanocoating of Nb 2 O 5 was prepared by solid-phase reaction. This method is simple and convenient, which is conducive to industrial production and commercialisation promotion. The Nb 2 O 5 surface coating can enhance the electrochemical properties of the cathode materials , as well as strengthen the thermal and structural stability, which can extend the battery life.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Chengyi Zhu,Jianxiong Liu,Xiaohua Yu,Yingjie Zhang,Xiaodong Jiang,Peng Dong,Yannan Zhang
4-Bromoanisole (4BA) is recommended for LiNi0.6Co0.2Mn0.2O2 (NCM 622) cathode materials as a safety electrolyte additive. The effect of anti-overcharge on NCM 622 cathodes are analyzed by cyclic voltammetry, constant current charge and discharge, AC impedance and scanning electron microscopy (SEM) measurement. The overcharge test results show that 4BA can be effectively electropolymerized at 4.45 V (vs. Li/Li + ), which can consume the overcharge current and protect the working electrode from voltage runaway. The time for the voltage rising to the overcharge state is availably delayed from about 16 hours to about 37 hours. The strategy can block off further oxidation of the active material and electrolyte, and finally promote the overcharge tolerance of the Li-ion batteries. Moreover, it is also found that the use of 4BA as a safety electrolyte additive does not obviously effect the electrochemical performance of NCM 622 and can effectively improve its cycle stability at high cut-off voltage (4.7 V).
研究领域:
材料科学
·
电化学
✓ 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）