NEW JOURNAL OF CHEMISTRY
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2025
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IF 2.5
Tiantian Wang,Lei Ni,Xu Sun,Hejie Lu,Haiqiang Li,Maosen Fu,Xiao Ma
Co-free binary cathode materials (LiNixMn1−xO2, x ≥ 0.5) are promising candidates for lithium-ion batteries (LIBs) due to their high specific capacity and low cost. The degradation of the low-temperature electrochemical performance of these materials not only hinders their practical application but also emerges as a critical research focus in energy storage technologies. In this work, the effect of Sm doping on the structure and electrochemical performance of LiNi0.55Mn0.45O2 (NM5545) cathode materials (x% Sm-NM5545, x = 0, 0.5, 1.0, 1.5) is systematically investigated over a wide temperature range (−10 to 45 °C). Sm doping significantly enhances the structural stability and enlarges interlayer spacing, which likely facilitates Li+ transport. Compared with undoped NM5545, the 1.0% Sm-NM5545 cathode materials exhibit remarkable improvements in capacity retention, which increases by 14.1%, 8.0%, and 9.4% after 100 cycles at temperatures of −10 °C, 25 °C, and 45 °C (1.0C, 3.0–4.45 V), respectively. Meanwhile, the discharge-specific capacity of 1.0% Sm-NM5545 cathode materials increases by 7.9 mA h g−1, 9.1 mA h g−1, and 12.9 mA h g−1 at the above respective temperatures. Electrochemical impedance spectroscopy and galvanostatic intermittent titration technique analyses confirm that Sm doping has enhanced the lithium-ion migration rate while reducing the charge transfer resistance in the modified materials. Furthermore, post-cycling characterization via scanning electron microscopy and X-ray photoelectron spectroscopy reveals that Sm doping effectively reinforces the structural integrity, suppresses crack propagation during high voltage cycling, and inhibits detrimental cathode–electrolyte interfacial reactions.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Honglin Yan,Yuan Ha,Tao Ye,Xiaoya Gao,Xiangting Yue,Zhimin Li
Ni-rich LiNi x Mn 1- x O 2 cathodes have been extensively probed to resolve the electrochemical performance degradation in the absence of Co 3+ compared to LiNi x Co y Mn 1- x - y O 2 cathodes for lithium-ion batteries. Herein, LiNi 0.6 Mn 0.4 O 2 (NM64) and a series of nonmagnetic Al 3+ ions substituted NM64 cathode materials are designed and prepared via a sol–gel route. It is found that the inferior electrochemical performance of NM64 derives from the magnetic frustration arising from Mn ions and the unstable Mn 3+ ions, which will lead to severe Li/Ni mixing, and weak structural and interfacial stabilities of the cathode. The superconducting quantum interference device (SQUID) analysis proves that the nonmagnetic Al 3+ ion can lower the Li/Ni disorder in NM64 cathode by relieving magnetic frustration. Moreover, the dQ/dV and XPS analyses confirm that both structural and interfacial stabilities are enhanced for NM64 cathode owing to Al 3+ substitution, contributing to fewer byproducts after a long cycle. Consequently, LiNi 0.582 Mn 0.388 Al 0.03 O 2 cathode delivers a high discharging capacity of 179 mAh g −1 at 1.0C with a capacity retention of 87.6% after 100 cycles. This study not only gives an in-depth understanding of the mechanism of electrochemical performance degradation for NM64 cathode, but also demonstrates an efficient solving approach through Al 3+ complementary substitution.
研究领域:
材料科学
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电化学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Energy
·
2024
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IF 9
Bao Zhang,Heng Wen,Keyi Xian,Na Lu,Chao Zheng,Zhiming Xiao,Xinyou He,Long Ye,Jiexi Wang,Lei Ming,Chunhui Wang,Xing Ou
Ultrahigh nickel cobalt-free layered oxide cathode is considered to be one of the most promising lithium-ion cathode materials due to its high specific capacity and low price. Unfortunately, high nickel cathode materials have problems such as high cation mixing, thermal stability and structure instability, and how to address these problems has been the direction of researchers. Introducing heteroatoms into bulk phase is an essential and effective method for dealing with the above issues. In this paper, the comprehensively reinforced crystal and framework structure has been obtained in LiNi 0.9 Mn 0.1 O 2 (NM-WMM) cathode material by the synchronously doping of W 6+ , Mg 2+ and Mo 6+ . Thanks to the pillar function of all the doping elements and robust metal-O bond of W 6+ and Mo 6+ , the structural and chemical stability of the designed materials have been effectively strengthened, contributing to enhance their cycling performance and high-temperature properties, and optimize the reaction kinetics synchronously. As expected, NM-WMM materials deliver a prominent capacity retention rate at both 25 °C (91 %, 200 cycles, 1 C) and 50 °C (93.9 %, 100 cycles, 1 C). This proves that the multi-element doping modification strategy is beneficial to improve the cyclic performance and thermal stability of Ni-rich Co-free cathode materials.
研究领域:
材料科学
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电化学
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能源存储
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固态化学
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电池技术
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2025
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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
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电化学
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储能技术
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表面工程
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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）