鋰離子電池富鋰正極材料的包覆改性研究進展

楊溢; 何亞鵬; 張盼盼; 郭忠誠; 黃惠

doi:10.13374/j.issn2095-9389.2020.11.04.003

鋰離子電池富鋰正極材料的包覆改性研究進展

doi: 10.13374/j.issn2095-9389.2020.11.04.003

楊溢^{1, 2},
何亞鵬^{1, 2},
張盼盼^{1, 2},
郭忠誠^{1, 2, 3},
黃惠^{1, 2, 3, ,}

1.
昆明理工大學冶金與能源工程學院，昆明 650093
2.
云南省冶金電極材料工程技術研究中心，昆明 650106
3.
昆明理工恒達科技股份有限公司，昆明 650106

基金項目: 國家自然科學基金資助項目（52064028，22002054，51504111）；中國博士后科學基金資助項目（2018M633418）

詳細信息

通訊作者:
E-mail: huihuanghan@kmust.edu.cn

中圖分類號: TM912.9
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- 被引次數: 0
出版歷程
- 收稿日期: 2020-11-03
- 網絡出版日期: 2021-02-01
- 刊出日期: 2022-01-08

Research progress on coating modification of lithium-rich cathode materials for lithium-ion batteries

YANG Yi^{1, 2},
HE Ya-peng^{1, 2},
ZHANG Pan-pan^{1, 2},
GUO Zhong-cheng^{1, 2, 3},
HANG Hui^{1, 2, 3
, ,}

1.
Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093, China
2.
Metallurgical Electrode Material Engineering Technology Research Center of Yunnan Province, Kunming 650106, China
3.
Kunming Hendera Science and Technology Co. Ltd., Kunming 650106, China

More Information

Corresponding author: E-mail: huihuanghan@kmust.edu.cn

摘要

摘要: 隨著新能源汽車及儲能行業的快速發展，傳統正極材料難以滿足人們對電池高能量、高密度鋰電池的要求。富含Li和Mn的層狀氧化物xLi₂MnO₃·(1–x)LiMO₂ (M=Ni，Mn，Co)，其高比容量可超過250 mA·h·g^–1，有希望成為下一代鋰離子電池最理想的正極材料。但是，富鋰材料仍存在首次循環不可逆容量高、循環性能差和倍率容量低等問題，為解決這些問題，本文闡述了富鋰正極材料的結構和電化學反應之間的構效關系，討論了金屬氧化物、金屬氟化物、碳、導電聚合物和鋰離子導體等涂層材料對富鋰正極材料電化學性能的影響規律及作用機理，同時還對以上涂層在富鋰正極材料中應用的優缺點進行了總結。最后，對鋰離子電池富鋰正極材料的包覆改性的未來發展發現作出展望。
- 鋰離子電池 /
- 富鋰材料 /
- 包覆改性 /
- 倍率性能 /
- 循環穩定性
Abstract: With the rapid development of new energy vehicles and the energy storage industry, traditional cathode materials often do not meet people’s expectations of high energy output and high density for lithium-ion batteries. The layered oxide xLi₂MnO₃·(1?x)LiMO₂ (M=Ni, Mn, Co), rich in Li and Mn, is expected to be an ideal anodic material for the next generation of lithium-ion batteries owing to its high specific capacity exceeding 250 mA·h·g^?1. However, the Li-rich materials still suffer from high irreversible capacity loss at the first cycle, poor cycle performance, and inferior rate capacity. The voltage decay mechanism of lithium-rich manganese-based cathode materials involves factors such as surface phase transition, anion redox, transition metal migration, and oxygen release. As a commonly used modification method, the coating can effectively solve these problems. At present, the coating modification mechanism of cathode materials mainly includes the following three types. (1) Surface coatings can reduce the direct contact between lithium-rich materials and electrolytes. They stabilize the interface, prevent excessive metal dissolution, and effectively prevent the surface structure of the active material from collapsing. (2) Surface coatings can reduce oxygen activity, improve irreversible oxygen loss, inhibit solid electrolyte interphase (SEI) film growth, and improve material thermal stability. (3) Surface coatings can improve the conductivity of the positive electrode active material, which builds a conductive network on the surface to provide a fast transmission channel for electrons and lithium ions. Surface modification can optimize the surface and structure of the lithium-rich layered material, and the modified material shows a higher discharge capacity and good cycle stability, with superior rate performance and thermal stability. This paper expounded upon the lithium-rich cathode material structure and electrochemical reaction between the structure–activity relationship and discussed the influence of metal oxides, metal fluoride, carbon, conductive polymer, and lithium-ion conductors on the coating material, the electrochemical performance of lithium-ion battery cathode materials, and the mechanism of action. We also summarized the advantages and disadvantages of the abovementioned coating in the application of lithium-ion battery cathode materials. Finally, future developments in the coating modification of lithium-rich cathode materials for lithium-ion batteries were discussed.
- lithium ion batteries /
- Li-rich materials /
- coating modification /
- rate performance /
- cycle stability

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圖 1 氧化鋁包覆富鋰納米管的合成路線示意圖^[52]

Figure 1. Schematic of the route for synthesizing Al₂O₃-coating Li-rich nanotubes^[52]

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圖 2 FATO包覆Li_1.2Mn_0.54Ni_0.13Co_0.13O₂顆粒中的氧空位機制示意圖^[53]

Figure 2. Schematic of oxygen vacancies mechanism in FATO-coated Li_1.2Mn_0.54Ni_0.13Co_0.13O₂ particles^[53]

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圖 3 LMNCAF合成的示意圖^[54]

Figure 3. Schematic of the synthesis of LMNCAF^[54]

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圖 4 （a）原始LNMO及不同比例CoF₂改性材料的循環性能^[57]；（b）充電狀態（4.8 V）下原始和1% MgF₂修飾富鋰電極的熱重曲線^[55]

Figure 4. (a) Cycling properties of bare LNMO and modified materials with different proportions of CoF₂^[57]; (b) DSC tracking of the original and 1% MgF₂–coated lithium-rich electrode under charged state (4.8 V)^[55]

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圖 5 HRTEM圖像和電子衍射圖譜。（a）由混合尖晶石和層狀結構組成的顆粒表面HRTEM圖像；（b）混合尖晶石結構的電子衍射圖譜；（c）層狀結構的電子衍射圖譜；（d）混合尖晶石和層狀結構合并后的電子衍射圖譜；（e）混合尖晶石結構的晶向指數；（f）層狀結構的晶向指數；（g）混合尖晶石和層狀結構合并后的晶向指數^[68]

Figure 5. HRTEM images and electron diffraction patterns: (a) HRTEM image of particle surface composed of mixed spinel and layered structure; (b) electron diffraction pattern of mixed spinel structure; (c) electron diffraction pattern of layered structure; (d) electron diffraction pattern of mixed spinel and layered structures combined; (e) orientation index of mixed spinel structure; (f) orientation index of layered structure; (g) orientation index of mixed spinel and layered structures combined^[68]

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圖 6 生物質葡萄糖作為碳源包覆富鋰材料示意圖^[71]

Figure 6. Schematic of biomass glucose as carbon source-coated lithium-rich material^[71]

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圖 7 （a）PI–LNMCO-450的TEM圖像；LNMCO和PI–LNMCO在2.0~4.8 V電壓范圍內的循環行為（b）和倍率性能（c）^[74]

Figure 7. (a) TEM images of PI–LNMCO-450 samples; cyclic behaviors (b) and rate performances (c) of LNMCO and PI–LNMCO in the voltage range of 2.0–4.8 V^[74]

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圖 8 （a）LiPPA–PPy的濕法涂裝過程；原始富鋰材料和LiPPA–PPy改性材料的循環性能（b）和倍率性能（c）^[75]

Figure 8. (a) Wet-coating process of LiPPA–PPy; The cyclic behaviors (b) and rate performances (c) of pristine Li-rich materials and LiPPA–PPy modified materials ^[75]

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圖 9 （a）Li_1.2Ni_0.2Mn_0.6O₂/PEDOT:PSS樣品合成示意圖；（b）PEDOT:PSS結構^[76]

Figure 9. (a) Synthesis of Li_1.2Ni_0.2Mn_0.6O₂/PEDOT:PSS samples; (b) structure of PEDOT:PSS ^[76]

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圖 10 （a）LiCoPO₄修飾Li_1.2Ni_0.18Mn_0.59Co_0.03O₂的TEM圖像；在400 °C（b）和500 °C（c）下煅燒制備的Li–Mn–PO₄涂層樣品的TEM圖像^[78]；在400 °C和500 °C下煅燒制備的Li–Mn–PO₄涂層樣品的循環性能（d）和倍率性能（e）^[79]

Figure 10. (a) TEM images of the LiCoPO₄-modified Li_1.2Ni_0.18Mn_0.59Co_0.03O₂; TEM images of the Li–Mn–PO₄-coated samples after calcination at 400 °C (b) and 500 °C (c)^[78]; cycle performances (d) and rate capabilities (e) of the as-prepared Li(Li_0.17Ni_0.25Mn_0.58)O₂ and Li–Mn–PO₄-coated samples after calcination at 400 and 500 °C^[79]

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