ACS Sustainable Chemistry & Engineering
·
2023
·
IF 8.4
Jing Wang,Youlong Xu,Yao Niu,Yali Liu,Xianghua Yao
A critical challenge in the commercialization of spinel lithium manganate materials is the bulk structure damage and capacity degradation due to manganese dissolution during battery operation. Hence, Li3PO4 with good ionic conductivity was homogeneously deposited on the surface of spinel lithium manganate by the sol–gel method, aiming to improve the stability and cycling of the spinel structure by an epitaxial layer. The structural and electrochemical characterizations reveal that the presence of the Li3PO4 epitaxial coating prevents the direct contact of the cathode surface and electrolyte, thus enhancing the stability of the structure and reducing the extent of manganese dissolution. Further studies have shown that the contribution of the Li3PO4 layer promotes the diffusion coefficient of lithium ions, which increases from 7.89 × 10–12 to 4.43 × 10–11 cm2 s–1. Meanwhile, the Li3PO4 coating regulates the concentration of oxygen vacancies on the surface of the spinel, effectively reducing the transfer resistance and increasing the electronic conductivity to 3.50 × 10–5 cm–1. Specifically, the discharge specific capacity of the 1.0 wt % Li3PO4-modified electrode is still 115.4 mAh g–1 after 300 cycles, with the capacity retention increased to 90.8%. Even at a high rate of 10C, it still demonstrates excellent rate capability, with the discharge specific capacity more elevated than that of the unmodified material at about 40 mAh g–1. This strategy can simultaneously solve the interfacial instability and bulk structure degradation, thus improving the electrochemical performance of lithium manganate materials.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
IONICS
·
2024
·
IF 2.4
Zheng Tingting,Wang Zhixing,Wang Siwu,Li Xinhai,Guo Huajun,Peng Wenjie,Wang Jiexi,Yan Guochun
Spinel LiMn 2 O 4 -based lithium-ion batteries are widely applied in electric two-wheeler and low-speed vehicles due to their low cost and low toxicity. Nevertheless, the Mn deposition at the anode originated from Mn dissolution of LiMn 2 O 4 causes a poor elevated temperature cycle life of graphite/LiMn 2 O 4 batteries. Herein, a graphite/LiFePO 4 cell with specific Mn 2+ added in the electrolyte is provided as an efficient evaluation method to research Mn 2+ deposition. Besides, an effective strategy by adding a ligand hexamethylenetetramine (HMTA) as an electrolyte additive is proposed to prevent Mn 2+ depositing. HMTA effectively “locks in” Mn 2+ through strong coordination, as confirmed by Raman spectroscopy and density functional theory (DFT) calculations. Moreover, the CV and XPS results indicate that the adsorption of HMTA is able to significantly inhibit side reactions at the anode/electrolyte interface. By adopting this strategy, the capacity retention of graphite/LiMn 2 O 4 cell is enhanced from 68.9% to 79.0% at 0.5 C after 100 cycles under 60 °C when adding 0.5% HMTA additive into the blank electrolyte. This work provides a new insight into revealing the mechanism of Mn 2+ regulation by introducing HMTA and improving the electrochemical performance of graphite/LiMn 2 O 4 batteries at elevated temperature.
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
APPLIED SURFACE SCIENCE
·
2023
·
IF 6.7
Wangqiong Xu,Qiling Li,Fengrui Sui,Shimei Guo,Ruijuan Qi,Cuiqiong Yan,Lijuan Chen,Shubiao Xia,Junming Guo,Zhe Li,Rong Huang,Feixiang Cheng
Ni doping is a commonly used strategy to improve the electrochemical performance of LiMn 2 O 4 . Uncovering the structural changes of Ni-doped LiMn 2 O 4 during electrochemical cycling, particularly at the atomic level, is important to understand the mechanism of the relationship between Ni doping and performance improvement. Herein, we investigate the chemical and structural evolutions of the Ni-doped LiMn 2 O 4 electrodes before and after 1000 cycles at 10 C with atomic resolution and correlate them with changes in the electrochemical properties . We found that Ni 2+ ions doped into the Mn 16d sites to form a more steady LiNi x Mn 2-x O 4 phase construction, which can effectively stabilize the spinel structure by hindering Jahn − Teller distortion. Comprehensive atomic imaging demonstrated that Ni doping can suppress the formation of the unexpected Mn 3 O 4 , and rock-salt MnO phases on the surface and subsurface of LiMn 2 O 4 during cycling, which is conducive to stabilizing the MnO 6 octahedron and inhibiting the migration of Mn. Resultantly, splendid long cycling stability of 88.92 % after 1000 cycles at 10 C (1 C = 148 mAh g −1 ) for the optimized LiNi 0.05 Mn 1.95 O 4 sample is presented. Our study provides an ingenious avenue for regulating the surface optimization and reconstruction of electrode materials .
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
·
2023
·
IF 15.1
Xiaoyu Zhao,Yaxin Gong,Kai Gao,Yanfei Wang,Hui Ying Yang
A composite electrode material, LiMn 2 O 4 -Pyr-2D, was designed by combining a 2D pyrazine-linked covalent organic framework (COF), namely Pyr-2D, with LiMn 2 O 4 (LMO). Pyridine (Pyr) was used to form a planar and conjugated structure, which enabled the formation of ordered and stable molecular building blocks with regular pores and uniform element distribution. This structural design effectively mitigated the rate of Mn dissolution and the Jahn-Teller effect-induced structural collapse of LMO at high temperatures, thereby significantly enhancing its resistance to elevated temperatures and improving the efficiency of lithium extraction from geothermal brine. Furthermore, the fast ion diffusion rate at high temperatures was utilized to improve the lithium extraction efficiency. The experimental results demonstrate that LiMn 2 O 4 -Pyr-2D exhibited an initial discharge capacity of 154.00 mAh/g in a LiCl solution at 60 ℃ and maintained a capacity retention rate of 92.52% after 20 cycles of lithium extraction in geothermal water from Tibet at 60 ℃. The unit energy consumption was 0.46 Wh/mol with an extraction capacity was 47.03 mmol/g. Overall, this approach introduces a novel and highly efficient method for electrochemically extracting lithium from high-temperature brine.
研究领域:
材料科学
·
电化学
·
能源材料
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
ELECTROCHEMISTRY
·
2020
·Vol. 88
·期 6
·532-539
·
IF 1.099
Ruifang CHEN,BiXia WEN,Changwei SU,Wei BAI,Junming GUO
LiMn2O4 cathodes are prepared by a rapid microwave-induced solution combustion method. Their initial discharge capacity is significantly improved by introducing trace Ni. For example, the LiMn1.975Ni0.025O4 (LMNO-0.025) cathode releases an initial discharge capacity of 134.1 mAh g−1 at 1 C, even 144.5 mAh g−1 at 0.5 C, which is far higher than of the pristine LiMn2O4 cathode (119.7 mAh g−1 at 1 C) and close to its theoretical capacity of 148.2 mAh g−1. After 1000 cycles, the capacity retention of the LMNO-0.025 sample reaches 56.53 % at 1 C, and it can be presented the higher capacity retentions of 66.79 % at 5 C and 66.89 % at 20 C. The robust structure stability proved by XRD, SEM and HRTEM data, and the good kinetics testified by CV and EIS data of the Ni-doped material are responsible to improve the high-rate capability and long cycle properties.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Chao Zou,Yun Huang,Ling Zhao,Wenhao Ren,Zhixing Zhao,Jiapin Liu,Xing Li,Mingshan Wang,Bingshu Guo,Yuanhua Lin
The electrode deterioration and capacity decay caused by the dissolution of transition metal ions have been criticized for a long time. The branched polyethyleneimine (PEI) was employed as a functional binder for spinel lithium manganese oxide (LiMn2O4, LMO) and layer structure lithium cobalt oxide (LiCoO2, LCO) to resolve the problem. Due to the chelation reaction of amine groups, PEI polymer binder can effectively absorb soluble transition metal ions, which is beneficial to reduce the loss of active materials. For PEI-based cathode, the uniform distribution of key components is achieved by the rapid curing process of water, which endow PEI-based cathode with a higher Li+ diffusion coefficient and improved electrochemical reaction kinetics. In addition, the fixed binder coating is favorable to protecting the active materials from parasitic reaction with the lithium hexafluorophosphate (LiPF6)-based electrolyte. Therefore, the PEI-based cell shows superior rate capability and long-term cycle performance. Functional binders of this study provide a simple and effective strategy to achieve higher capacity and longer cycle stability for transition metal oxide electrodes.
研究领域:
材料科学
·
电化学
✓ 已验证
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2026
·
IF 9.1
Jing Li,Beichen Sun,Wenbiao Ma,Xiao Du,Fengfeng Gao,Zhonglin Zhang,Xiaogang Hao
Electrochemically switched ion exchange (ESIX) is a promising technology for lithium extraction from high Mg/Li ratio salt lake brines, yet conventional lithium manganese oxide composite electrodes suffer from loose interfacial binding and particle agglomeration. To address this issue, for the first time, we developed a precursor-hydrothermal lithiation strategy that integrates MnOOH crystal seed pre-anchoring and C-O-Mn interfacial chemical bonding to fabricate a uniform and stable carbon nanotube/lithium manganese oxide composite membrane electrode. In this strategy, MnOOH nanoparticles were pre-loaded onto carbonylated carbon nanotubes as crystal seeds and subsequently converted into spinel lithium manganese oxide, while the C-O-Mn interfacial chemical bonds were formed to anchor the lithium manganese oxide nanoparticles onto the carbon nanotube scaffold. The resulting composite membrane exhibited a low charge transfer resistance of 21.5 Ω and fast lithium ion diffusion kinetics (2.68 × 10 −12 cm 2 ·s −1 ). When tested in actual brine from the Qarhan Salt Lake, it achieved a lithium intercalation capacity of 20.21 mg·g −1 and a Li + /Mg 2+ separation factor of 116, while maintaining excellent cycling stability with a capacity retention rate of 93.07%, significantly outperforming the control samples prepared by conventional methods. Mechanistic analysis suggests that the C-O-Mn interfacial chemical bonds contribute to enhanced electron/ion transport, facilitate the stabilization of the interfacial structure, and help suppress the detachment of active materials, thereby substantially enhancing the electrode performance. This work provides an interfacial engineering strategy for high-performance ESIX electrodes.
✓ 已验证
DOI
高影响因子
RSC Advances
·
2026
·Vol. 16
·期 30
·27223-27231
·
IF 6.1
Wangqiong Xu,Xianrong Li,Xueqing Kang,Lijuan Chen,Baiyan Guo,Qiling Li,Kun Xu,Yiming Cao,Zhe Li,Yongsheng Liu
Spinel LiMn2O4 is one of the most promising cathode materials due to its green, low-cost, and abundant resources. However, issues such as manganese dissolution, electrolyte decomposition, and inadequate cycling stability have hampered its further application. Herein, we designed a modification strategy for LiMn2O4 cathodes using N-methyl-2-pyrrolidone (NMP), water, and ethanol mixed solution as the carbon source to in situ coat LiMn2O4 truncated octahedra particles. It is found that the amorphous carbon layer serves as a structure stabilization agent to enhance the electrochemical performance of LiMn2O4. Specifically, the coating carbon layer can effectively minimize the acid corrosion, facilitate Li+ diffusion, improve the interface between the electrode and electrolyte, and strengthen cycle stability. As a result of these improvements, the optimized 2 mL C/LiMn2O4 sample exhibits outstanding long-term performance, with an initial discharge specific capacity of 107.6 mAh g−1 and a capacity retention of 50.56% after 2000 cycles at 10C. This outstanding performance makes our material a promising candidate cathode for lithium-ion battery in future applications.
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2025
·
IF 5.5
Shiqiang Zhong,Jingwei Liu,Yongcong Huang,Yulin Cao,Feng Wu,Xuhui Li,Dawei Luo,Zhouguang Lu,Hua Cheng
Spinel LiMn2O4 (LMO) is a promising fast-charging cathode material because its unique three-dimensional Li-ion diffusion channels offer favorable ionic diffusivity. However, LMO encounters rapid structural degradation at high current densities. To tackle this issue, we introduce K+ ions into the interstitial 16c sites to stabilize LMO, thereby achieving excellent fast-charging capability. The K-LMO retains 75% of its theoretical capacity at an ultrahigh current density of 1.48 A g–1 (10 C, corresponding to a charging time of 5 min). Comprehensive characterizations demonstrate that the incorporation of K+ into LMO expands the LiO4 space, strengthens the Mn–O bonds and suppresses the Jahn–Teller effect, leading to improved Li-ion mobility and enhanced stability of the diffusion channels. Additionally, the volume variation induced by cycling under a high charge state is efficiently suppressed through a solid-solution transition, thus preventing structural degradation against long-term cycling. Given this, this study presents an attractive candidate material for the cathode of fast-charging lithium-ion batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
WASTE MANAGEMENT
·
2025
·
IF 7.1
Yuxue Zhang,Zhaoyong Liu,Jiahui Wang,Hui Du,Qi Sun,Ruitong Gao,Zhenming Xu
Recycling Li from spent lithium ion batteries (SLIBs) in an efficient and highly selective manner could protect the environment and introduce the circular economy principle to society. Simultaneously, the urgent need to address plastic waste, particularly polyvinyl chloride (PVC), has become a global concern. In this work, a strategy for Li extraction through synergetic pyrolysis of LiMn 2 O 4 cathode materials (LMO) and PVC is proposed. Under optimal conditions, the recovery rates of lithium and manganese reached 99.89 % and 0.02 %, respectively, demonstrating efficient separation of these elements. Temperature was found to play a critical role in the leaching rates of lithium and manganese by promoting the decomposition and reduction of LMO. Additionally, kinetic analysis shows that the activation energy ( E a ) of the synergetic pyrolysis is 139.60 KJ/mol, and the pyrolysis mechanism satisfies third-order reaction process. Eventually, the proposed mechanism involves the synergistic effects of chlorination and reduction reactions. First, HCl is generated by PVC pyrolysis under the catalytic effect of LMO. Then, the chlorination of HCl with LMO occurs by capturing structural oxygen and generating LiCl and MnCl 2 . Simultaneously, the reduction reaction between the reducing species generated by PVC pyrolysis and LMO occurs to form Li 2 O and MnO, ultimately enabling the separation of lithium and manganese. Overall, this paper presents a novel approach for future applications by providing a theoretical basis for selective Li extraction.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Wangqiong Xu,Yonghui Zheng,Yan Cheng,Ruijuan Qi,Hui Peng,Hechun Lin,Rong Huang
It is well known that the electrochemical performance of spinel LiMn2O4 can be improved by Al doping. Herein, combining X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and spherical aberration-corrected scanning transmission electron microscopy (Cs-STEM) with in situ electron-beam (E-beam) irradiation techniques, the influence of Al doping on the structural evolution and stability improvement of the LiMn2O4 cathode material is revealed. It is revealed that an appropriate concentration of Al3+ ions could dope into the spinel structure to form a more stable LiAlxMn2–xO4 phase framework, which can effectively stabilize the surface and bulk structure by inhibiting the dissolution of Mn ions during cycling. The optimized LiAl0.05Mn1.95O4 sample exhibits a superior capacity retention ratio of 80% after 1000 cycles at 10 C (1 C = 148 mA h g–1) in the voltage range of 3.0–4.5 V, which possesses an initial discharge capacity of 90.3 mA h g–1. Compared with the undoped LiMn2O4 sample, the Al-doped sample also shows superior rate performance, especially the capacity recovery performance.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2024
·Vol. 48
·期 17
·7911-7920
·
IF 2.7
Pengchao Liang,Yuanchao Li,Xiangzhen Xiao,Shumin Fan,Jingjing Ma,Jingjie Liu,Yongqiang Dong,Yuhang Zong,Guangri Xu,Li Yang
Although they possess a high working voltage and environmental compatibility, and are low in cost with abundant resources, the poor cycling performance and rapid capacity attenuation of LiMn2O4 cathodes at high temperature restrict their extensive application. In this study, LiMn2O4 materials are synthesized by a simple rheology-assisted solid-phase method using citric acid as an additive. The citric acid improves the uniformity of the mixed raw materials, resulting in a reduction in particle agglomeration. Consequently, the synthesized LiMn2O4 shows an initial capacity of 117.4 mA h g−1 with a capacity retention of 79.50% at 2C after 300 cycles and 54.78% of the initial discharge capacity at 20C. This work provides a strategy for modifying multicomponent transition metal oxides for advanced lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机固体化学
·
电池技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）