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
JOURNAL OF POWER SOURCES
·
2025
·
IF 7.9
Jiao Ma,Qin Zhu,Zhihui Qian,Wei Bai,Rui Liu,Long Shi,Yongsheng Yang,Yujiao Guo,Mingwu Xiang,Junming Guo
The drawbacks of Jahn-Teller (J-T) effect, capacity decay at high temperature and the dissolution of Mn generated at elevated current density limit the large-scale application of LiMn 2 O 4 batteries . Herein, a Si 4+ /Al 3+ co-doping strategy of LiMn 2 O 4 is carefully developed to stabilize the [MnO 6 ] framework, thereby inhibiting the J-T distortion and ultimately alleviating Mn dissolution. The incorporation of Si 4+ and Al 3+ in LiMn 2 O 4 promotes the formation of a single-crystal truncated octahedral structure, with preferential grain growth along the {111}, {100} and {110} crystal plane, which decreases Mn dissolution and enhances the Li + transfer pathways. Furthermore, the integration of Si 4+ /Al 3+ co-doping producing smaller particles can shorten the migration paths of electrons and ions. Consequently, the optimized LiSi 0.05 Al 0.09 Mn 1.86 O 4 displays a decent initial discharge specific capacity of 103.2 mAh·g −1 and an excellent capacity storage percentage of 79.7 % after 1000 cycles at 10 C. Meanwhile, the optimal sample also exhibits respectable first discharge capacities of 91.9 mAh·g −1 and 61.8 mAh·g −1 at ultra-high rates of 20 C and 40 C, along with superior capacity storage ratios of 70.9 % and 70.7 % after 1000 cycles. More importantly, the optimized sample shows remarkable first discharge specific capacity of 107.1 mAh·g −1 at 55 °C and 10 C and exciting capacity storage rate of 61.9 % after 500 cycles. This study serves as a guide for advancing high-performance, high-stability LiMn 2 O 4 cathode materials for use in lithium-ion batteries.
研究领域:
材料科学
·
电化学
·
能源存储
·
无机化学
·
固态化学
·
锂离子电池
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Bao Zhang,Yongkang Liu,Yunfeng Gu,Ziliang Feng,Enfeng Zhang,Peng Luo,Quanyi Zhang,Peng Dong,Yingjie Zhang,Yannan Zhang
Spinel lithium manganate (LiMn 2 O 4 ) is considered a highly promising cobalt-free cathode material for lithium-ion batteries (LIBs) owing to its three-dimensional Li-ion diffusion channels and the abundance of manganese. However, its practical applications are limited due to the substantial capacity deterioration induced by the Jahn-Teller effect and interfacial instability with the organic electrolyte. In this work, we propose a polyanion-based surface engineering strategy that enables simultaneous doping and the formation of a protective coating on the LiMn 2 O 4 cathode. Boric acid surface modification can selectively stabilize the MnO₆ octahedron, while effectively suppressing manganese dissolution and interfacial side reactions. Additionally, the partial surface boron component reacts with PF 6 − in the electrolyte to form thermodynamically stable BF 4 − , which reduces the generation of HF in the electrolyte and stabilizes the cathode electrolyte interphase (CEI). Therefore, the modified BO3-LMO exhibits remarkable cycling stability, with a capacity retention rate of 80.6 % after 900 cycles at 1C, which is significantly superior to that of the unmodified LMO (61.1 %). Additionally, the BO3-LMO demonstrates excellent rate capability and thermal stability, retaining high performance even at elevated temperatures (55 °C) and under high-rate operation (5C). Through a combination of advanced characterization techniques—such as XRD refinement, XPS, HR-TEM and density functional theory calculations, we uncover the origins of the improved electrochemical stability after surface modification. The BO3-LMO demonstrates a higher density of states at the Fermi level, stronger Mn O electron bonding, and a lower lithium-ion diffusion energy barrier. This integrated strategy not only solves the interfacial instability and structural degradation challenges but also establishes a scalable strategy for designing high-performance, cobalt-free spinel manganese-based lithium-ion batteries (LIBs).
研究领域:
材料科学
·
电化学
·
储能技术
·
表面工程
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）