JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 55
·期 7
·2913-2922
·
IF 3.442
Zhong Zeqin,Chen Lingzhen,Huang Shaozhen,Shang Weili,Kong Lingyong,Sun Ming,Chen Lei,Ren Wangbao
Single-crystalline LiNi 0.5 Co 0.2 Mn 0.3 O 2 (denoted as SC-523) with micron size had been successfully synthesized through a facile method. Electrochemical impedance spectroscopy and differential scanning calorimetry were carried out to identify the improved electrochemical performance and desired thermal stability. Even after 100 cycles, SC-523 still delivered a discharge capacity of 151.1 mA h g −1 (capacity retention with 90.3%) at 1 C in voltage range from 3.0 to 4.5 V (vs. Li/Li + ), while polycrystalline spherical LiNi 0.5 Co 0.2 Mn 0.3 O 2 (denoted as PC-523) only exhibited 141.7 mA h g −1 (capacity retention with 78.4%). Besides, SC-523 shows a higher decomposition temperature of 332.13 °C, 14.61 °C higher than that of PC-523 during the thermal decomposition. Consequently, single-crystalline particles with robust morphological integrity ensure the enhanced cycling stability and thermal 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
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Hao Chen,Li Xiao,Pengcheng Liu,Han Chen,Zhimei Xia,Longgang Ye,Yujie Hu
Herein, a strategy is presented for improving the electrochemical performance of a LiNixCoyMn1–x–yO2 layered oxide involving the coating of rock salt-type LiTiO2 on the surface via a hydrothermal method followed by a calcination process. A thickness of approximately 10 nm of LiTiO2 coated on the surface of LiNi0.5Co0.2Mn0.3O2 (NCM523) has been achieved, and the optimal molar ratio (LiTiO2/NCM523) is found to be 1.0 mol %. The LiTiO2@LiNi0.5Co0.2Mn0.3O2 when used as a cathode material exhibits not only a higher capacity retention but also a more enhanced rate performance in comparison with that of pristine NCM523. The LiTiO2 layer protects the NCM523 active particles from being eroded by the electrolyte and reduces the volume change of the electrode active particles before and after lithium-ion intercalation/deintercalation during cycling. These new findings contribute toward the design of a stable structured nickel-based cathode material for lithium-ion batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
Materials Today Communications
·
2023
·
IF 3.8
Mihong Cao,Luyi Wang,Qian Zhang,He Zhang,Shengwen Zhong,Jun Chen
In this work, a conductive slurry containing CNTs is used as a modification reagent for the Super-P (SP) conductive agent. After CNTs is recombined with SP, spherical SP particles with a diameter of about 60 nm are evenly dispersed on the surface of CNTs nanotubes with a diameter of 20 nm, which effectively improves the specific surface area of the conductive agent. As a result, the battery using 1.5 % CNTs/SP composite conductive agent shows a smaller EIS impedance value, which makes the comprehensive behaviors of the LiNi 0.5 Co 0.2 Mn 0.3 O 2 battery significantly improved. The CNTs/SP battery shows larger CV curve area and smaller potential difference between oxidation and reduction peaks. In addition, the initial charge and discharge capacity of CNTs/SP battery are 181.7 and 184.7 mAh/g respectively with initial Coulombic efficiency of 98.4%, which are much higher than the pristine SP battery (173.7 and 182.0 mAh/g respectively with initial Coulombic efficiency of 95.4 %). After 70 cycles, the discharge capacity of CNTs/SP battery can still remain at 175.3 mAh/g with capacity retention ratio of 97.2 %, which are also much higher than the pristine SP battery (142.5 mAh/g with capacity retention ratio of 82.8 %). Moreover, compared with the pristine SP batteries, the CNTs/SP batteries show larger discharge capacities at different rates of 0.2 C, 0.5 C, 1.0 C, 2.0 C, 3.0 C and 5.0 C. After combining SP with CNTs nanowires, the discharge capacity, initial coulombic efficiency, cycle stability and rate capability of LiNi 0.5 Co 0.2 Mn 0.3 O 2 electrode are effectively improved, which provides a new idea for the development of novel conductive agent for high-performance cathode materials of lithium ion batteries .
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
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Lecai Wang,Li Li,Xiaoxiao Zhang,Feng Wu,Renjie Chen
Compound-hierarchical-sphere-structured LiNi0.5Co0.2Mn0.3O2 was synthesized to improve the electrochemical performance of this material in lithium-ion battery cathodes. The product was found to have a large specific surface area, good electron and ion conductivities, a stable interface, and a robust nano/microhierarchical structure, all of which improved the rate capability, capacity, and cycling stability of this material. When this material was cycled between 3.0 and 4.3 V, a high discharge capacity of 180.8 mA h g–1 was obtained at 0.2C with 94.0% capacity retention after 100 cycles. In addition, a superior discharge capacity of 148.9 mA h g–1 was observed at a high current density of 1600 mA g–1. This compound-hierarchical-sphere LiNi0.5Co0.2Mn0.3O2 is readily prepared using our ternary coprecipitation method. We also propose an effector unit theory to explain the enhanced cycling stability of this substance and believe that the present results will assist in the design of cathode materials for lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Jishen Hao,Zhiyong Yu,Hanxing Liu,Wei Song,Jun Liu,Linghua Kong,Chuanhua Li
Herein, NiF 2 artificial interface was proposed for the first time to enhance the electrochemical performances of LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523) under 4.5 V. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images verify NiF 2 layer is successfully constructed on the surface of NCM523. The 1.0 wt% NiF 2 -modified NCM523 delivers a much higher capacity retention (86.9%) than pristine sample (69.0%) after 100 cycles under 4.5 V at 30 °C, even exceeding pristine NCM523 under 4.2 V (82.2%). Beyond that, the cycling stability of NCM523 under 4.5 V at 55 °C is also visibly improved due to the NiF 2 protective layer. Electrochemical impedance spectroscopy analyses confirm that NiF 2 suppresses the increase of interface resistance and therefore makes for the interface kinetics behaviors during cycling. In addition, the measurements of SEM, TEM and XPS support that the inhibition of the SEI (solid electrolyte interphase) growth can be attributed to the restrained side reactions between electrolyte and NCM523 by NiF 2 artificial layer at 4.5 V.
研究领域:
材料科学
·
电化学
·
电池技术
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 36
·17120-17128
·
IF 3.3
Tangzhe Cao,Huaming Xie,Ying Lei,Wei Zou,Hui Li,Kang Yang,Tong Zan,Liming Li,Yongxian Fang
Polyvinylidene fluoride (PVDF) binder is an important part of lithium-ion batteries, where a slight structural difference can significantly affect the capacitance and service life of batteries. Herein, ATR-FTIR technology and a rheological test were employed to investigate the crystal forms and rheological behavior of three different PVDF binders, respectively. The results showed that PVDF-CG has low molecular weight, high α/β phase ratio, strong adhesive action and stripping strength, which are closely associated with the durability and electrochemical properties of LiNi0.5Co0.2Mn0.3O2 single-crystal (denoted as SC) materials. The SCs with PVDF-CG binder exhibited a capacity retention of 93.44% after 100 cycles at a rate of 1C and high rate performance (92 mA h g−1 at 10C), which was higher than that of PVDF-HSV900 (90.31%, 86 mA h g−1 at 10C) and PVDF-Solvay 5130 (90.52%, 72 mA h g−1 at 10C). The XPS and HR-TEM analysis showed that the cycled SCs bonded with HSV900 and Solvay 5130 as binders suffered from severe interface structural degradation, while SCs with PVDF-CG maintained a well-layered structure and the formation of a surface NiO-like rock-salt phase was greatly inhibited. This work demonstrated that the capacity, rate capability and interface stability of SC cathodes are significantly affected by the mode and strength of the adhesion and stripping strength of PVDF binders, which are closely associated with α/β phase ratios, providing a useful reference for the development of efficient binders.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2024
·
IF 7.1
Zejia Wu,Jiashu Yuan,Hui Wang,Zaifa Pan,Jie Gao,Yonggao Xia
With the wide application of ternary lithium-ion batteries, the increased usage of batteries has resulted in a corresponding rise in the amount of discarded batteries. Here, we propose an efficient and prioritized lithium extraction process with a low environmental impact for the recovery of valuable metal components from spent LiNi0.5Co0.2Mn0.3O2 cathode materials. SO2 calcination–water leaching was used to recover Li, while H2SO4 acid leaching facilitated the recovery of Ni, Co, and Mn, yielding a precursor solution for the treatment of discarded NCM batteries. The effects of calcination temperature, calcination time, water leaching time, water leaching liquid–solid ratio, different battery ratios, acid leaching time, acid leaching liquid–solid ratio, and acid leaching temperature were optimized. The acid leaching process was controlled by surface chemical reactions through kinetic analysis. Under optimal conditions, Li was converted to soluble Li2SO4, achieving an impressive leaching rate of 99.7%. Ni, CO, and Mn were converted to their respective oxides. Furthermore, it was demonstrated that the formation of Li2Mn(SO4)2 from Mn with Li during calcination enhances the leaching efficiency across different battery composition ratios. The activation energies of Ni, Co, and Mn during the acid leaching process were determined by kinetic calculations, yielding values of 130.19, 133.05, and 134.09 kJ mol–1, respectively. This study provides a novel method for recycling spent NCM cathode materials.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Pengcheng Zhao,Yao Li,Xiaoyu Wang,Xiaoman Liu,Pei Gao,Peng Guo,Xiaoxiang Wang,Chunfei Wu,Boxiong Shen
With the large-scale application of power batteries, a large number of spent lithium-ion batteries (LIBs) will be formed in recent years. The improper disposal of spent LIBs will pose significant environmental pollution. LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM), as a typical type of LIBs cathodes material, are widely used and can be highly recycled. However, the existing hydrometallurgical and pyrometallurgical recycling processes consume large amounts of energy and introduce serious secondary pollution. This work presents a simple straightforward direct regeneration process that uses urea solvothermal treatment followed by calcination to obtain urea-regenerated spent NCM (UR-S-NCM). Surprisingly, the specific capacity of the regenerated NCM of UR-S-NCM recovers completely and reaches 166 mAh/g, higher than that of fresh NCM (F-NCM) at 156 mAh/g. After 100 charge/discharge cycles, the specific capacity of UR-S-NCM is 37 % higher than that of F-NCM at the same condition. Additionally, the CO 2 emissions per kilogram of the regenerated UR-S-NCM are only 1.79 kg, about 31 % of pyrometallurgy and 48 % of hydrometallurgy, respectively. The surface smoothness, grain boundaries and layered structure of UR-S-NCM are recovered from S-NCM to the same situation of F-NCM. Smooth surface facilitates Li + migration into and out of UR-S-NCM, grain boundaries reduction diminishes electrolyte corrosion, and the layered structure accommodates more Li + compared to the spinel structure of S-NCM. This work provides an eco-friendly direct regeneration process and offers a new insight for LIBs regeneration.
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 APPLIED ELECTROCHEMISTRY
·
2025
·Vol. 56
·期 1
·13
·
IF 3
Zhang Weijian,Han Jiaxing,Zhao Yuhui,Zhang Wei,Bao Yingqing,Wu XiaoZhen,Zhen Aigang,Zhu Binglong,Zhang Chunqiang,Qin Hengfei,Zhuang Yan
The rapid expansion of the lithium-ion battery market has intensified the need for recycling and regeneration of used lithium-ion batteries. The present research aimed to directly regenerate secondary agglomerated particles derived from spent lithium nickel cobalt manganese oxide (LiN 0.5 Co 0.2 Mn 0.3 O 2 ) cathode materials into single-crystal particles by employing a ternary molten salt mixture composed of lithium hydroxide, lithium carbonate, and sodium sulfate. The effects of calcination temperature (800 ℃, 850 ℃, and 900 ℃) and calcination duration (10, 12, and 14 h) on the electrochemical performance of the regenerated materials were investigated. Electrochemical evaluation indicated that calcination at 850 °C for 12 h yielded a discharge-specific capacity of 116.7 mAh g⁻¹ during the first cycle at a rate of 1 C (1 C = 160 mAh g⁻¹) and maintained a capacity retention of 84.4% after 400 cycles at 1 C. The regeneration process effectively restored the layered crystal structure of the cathode material, and the regenerated samples exhibited electrochemical properties comparable to those of commercial single-crystal counterparts, confirming the feasibility of using ternary molten salts for direct regeneration of spent lithium nickel cobalt manganese oxide cathodes. Graphical
✓ 已验证
产品关联
DOI
高影响因子
npj Computational Materials
·
2022
·Vol. 8
·期 1
·1-9
·
IF 12.256
Sha Wuxin,Guo Yaqing,Cheng Danpeng,Han Qigao,Lou Ping,Guan Minyuan,Tang Shun,Zhang Xinfang,Lu Songfeng,Cheng Shijie,Cao Yuan-Cheng
LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523) has become one of the most popular cathode materials for current lithium-ion batteries due to its high-energy density and cost performance. However, the rapid capacity fading of NCM severely hinders its development and applications. Here, the single crystal NCM523 materials under different degradation states are characterized using scanning transmission electron microscopy (STEM). Then we developed a neural network model with a two-sequential attention block to recognize the crystal structure and locate defects in STEM images. The number of point defects in NCM523 is observed to experience a trend of increasing first and then decreasing in the degradation process. The space between the transition metal columns shrinks obviously, inducing dramatic capacity decay. This analysis sheds light on the defect evolution and chemical transformation correlated with layered material degradation. It also provides interesting hints for researchers to regenerate the electrochemical capacity and design better battery materials with longer life.
研究领域:
材料科学
·
电化学
·
人工智能
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Chao Chen,Tao Tao,Wen Qi,Hong Zeng,Ying Wu,Bo Liang,Yingbang Yao,Shengguo Lu,Ying Chen
LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM 523) is one of the commercialized NCM cathode materials for lithium ion batteries . In this work, we demonstrate that a 0.5 wt% SiO 2 nanoparticles-coated NCM 523 shows an improved cycling performance and thermal stability, compared with the pure NCM 523. The structural integrity of the NCM 523 during cycling processes can be maintained by the SiO 2 coating layer with a thickness of about 20–30 nm. The 0.5 wt% SiO 2 -coated NCM 523 cathode exhibits a capacity retention of 82.5% over 100 cycles at 0.1 C between 2.5 and 4.3 V, while that of the pristine material is only 68%. Also, the 0.5 wt% SiO 2 -coated sample exhibits a higher reversible capacity (153.4 mAh g −1 ) and better capacity retention (92.4%) over 50 cycles than those of the pure NCM 523 (114.3 mAh g −1 , 66.0%) in the electrolyte with lithium difluoro (oxalato)borate at 1 C in the voltage range of 2.8–4.5 V. The SiO 2 coating layer plays a critical role in improving the electrochemical performance of NCM 523 cathode.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米材料
·
电池技术
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
·
2020
·Vol. 45
·期 4
·6041-6053
·
IF 3.741
Yanfang Xie,Fuzhong Wu,Xinyi Dai,Yi Mai,Yijing Gu,Huixin Jin,Junqi Li
Summary Nickel-cobalt-manganese ternary cathode materials are known as one of the most promising future cathode materials for Li-ion batteries (LIBs) due to their high discharge capacity, environmental friendliness, and low cost. In this paper, submicron LiNi 0.5 Co 0.2 Mn 0.3 O 2 (NCM523) primary particles with good crystallinity and dispersibility have been synthesized combine a coprecipitation method used ethanol as solvent with solid-phase sintering technology. A feeding strategy through separate dropping of sodium carbonate and ammonia is adopted; the structure and properties of NCM523 under different pH conditions are investigated. It is found that the NCM523 synthesized at pH = 8 (NCM523-8) exhibits a uniform particle size of about 300 nm, with good crystallinity. The NCM523-8 exhibits an excellent high-potential cycling performance, with an initial discharge capacity of 193.6 mAh g −1 at 0.2 C in the voltage of 3.0 to 4.5 V, and the capacity retention is 91% after 100 cycles. It also shows excellent rate performance with a reversible capacity of 130 mAh g −1 at 5 C. The superior high-potential electrochemical performance is attributed to the improved lithium-ion diffusion coefficient and stabilized structure by the special structural characteristics as evidenced by cyclic voltammetry, electrochemical impedance spectroscopy, and X-ray diffraction.
研究领域:
材料科学
·
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）