Microwave assisted preparation of LiFePO4/C coated LiMn1.6Ni0.4O4 for Li-ion batteries with superior electrochemical properties
Microwave assisted preparation of LiFePO4/C coated LiMn1.6Ni0.4O4 for Li-ion batteries with superior electrochemical properties
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DOI：
10.1016/j.apmt.2022.101697
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发表时间：
2023-02
影响因子：
8.3
通讯作者：
F. Vásquez;N. Rosero-Navarro;R. Jalem;A. Miura;Y. Goto;Y. Tateyama;J. A. Calderón;K. Tadanaga
中科院分区：
文献类型：
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作者：
F. Vásquez;N. Rosero-Navarro;R. Jalem;A. Miura;Y. Goto;Y. Tateyama;J. A. Calderón;K. Tadanaga
LiMn1.6Ni0.4O4（LMNO）尖晶石是一种很有前途的高电位无钴电极。然而，它对电解质的化学稳定性相对较差。无机涂料由于具有优异的化学和电化学性能而得到了广泛的应用。一个很有前途的例子是LiFePO4/C （LFP/C）橄榄石包覆的LMNO尖晶石颗粒，其中橄榄石提供了很高的化学稳定性。在大气合成条件下，它们之间的化学不相容性使得该过程极具挑战性。本文提出了一种简单实用的微波辐照法制备LFP/ c包覆LMNO的方法。该工艺显著改善了尖晶石结构的晶体有序性，并在避免副反应的同时提供了两种材料之间充分的物理相互作用。采用LFP/C包覆LMNO电极的锂离子电池在25°C和60°C下的放电容量均高于未包覆尖晶石的锂离子电池。此外，LFP/C涂层的LMNO颗粒在25°C下的循环性能（高达500次循环）和60°C下的C速率性能优越，而使用未涂层尖晶石则不可能。
LiMn1.6Ni0.4O4(LMNO) spinel is a promising cobalt-free electrode for high potential applications. However, its chemical stability against electrolytes is relatively poor. Inorganic coatings have widely used to achieve superior chemical and electrochemical properties. A promising example is LiFePO4/C (LFP/C) olivine coated LMNO spinel particles, in which olivine provides a high chemical stability. Chemical incompatibility between them during atmospheric synthesis conditions makes the process extremely challenging. Herein, we propose a simple and practical route to prepare LFP/C-coated LMNO using microwave irradiation. This process significantly improves the crystallographic order of the spinel structure and provides sufficient physical interaction between both materials while avoiding side reactions. Li-ion battery using LFP/C-coated LMNO electrode exhibits a higher discharge capacity at 25°C and 60°C than those of uncoated spinel. Moreover, cyclability (up to 500 cycles) at 25°C and C-rate capability performances at 60°C are superior in LFP/C-coated LMNO particles and not possible using uncoated spinel.