文章信息/Info

Title:

In-Situ Surface Modification of LNMO Cathode with LYTP for Lithium-Ion Batteries

文章編號:

1674-3962(2025)10-0922-07

作者:

王正午; 黃憶雪; 張恩鳳; 劉永康; 豐子良; 張寶; 董鵬; 張英杰; 張雁南

昆明理工大學冶金與能源工程學院 鋰離子電池及材料制備技術國家地方聯合工程研究中心，云南 昆明 650093

Author(s):

WANG Zhengwu;  HUANG Yixue;  ZHANG Enfeng;  LIU Yongkang;  FENG Ziliang;  ZHANG Bao;  DONG Peng;  ZHANG Yingjie;  ZHANG Yannan

National and Local Joint Engineering Laboratory for Lithium-Ion Batteries and Materials Preparation Technology,Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology,Kunming 650093, China

關鍵詞:

鋰離子電池; 高電壓鎳錳酸鋰; 表面包覆; 磷酸鈦釔鋰; 電化學性能

Keywords:

lithium-ion batteries;  high voltage lithium nickel manganese spinel (LNMO); surface coating;  yttrium lithium titanium phosphate (LYTP); electrochemical performance

分類號:

TQ131.1+1; TM912

DOI:

10.7502/j.issn.1674-3962.202403012

文獻標志碼:

A

摘要:

尖晶石LiNi0.5Mn1.5O4（LNMO）因其高工作電壓（>4.7 V）和優良的質量能量密度（≥650 Wh·kg-1）可以成為一種有前途的鋰離子電池（lithium-ion batteries,LIBs）無鈷正極材料。然而，在高工作電壓下較差的循環性阻礙了其商業應用。采用凝膠溶膠法在LNMO表面成功原位構筑了一層無機導電Li1.4Y0.4Ti1.6(PO4)3(LYTP)包覆層。對改性前后LNMO的表面形貌、晶體結構和電化學性能進行了綜合研究。結果表明，LYTP表面改性具有良好的多功能保護層作用，有效降低了錳在電解液中的溶解，提高了鋰離子的遷移效率。值得注意的是，LNMO@LYTP的容量保持率在500次循環后仍高達82%，顯著高于未包覆的LNMO正極。即使在10C倍率條件下，LNMO@LYTP也具有116 mAh·g-1的放電比容量。該研究為錳基正極材料的表面改性領域提供了數據，并為進一步提高其他高壓錳基LIBs正極材料的電化學性能提供了思路。

Abstract:

Spinel LiNi0.5Mn1.5O4 (LNMO) is a promising cobalt-free cathode material for lithium-ion batteries (LIBs) due to its high operating voltage (>4.7 V) and excellent bulk energy density (≥650 Wh·kg-1). However, the commercial application of this material is hindered by its poor cyclability at high operating voltage. This work successfully constructed an inorganic conductive coating layer, Li1.4Y0.4Ti1.6(PO4)3 (LYTP), on the surface of LNMO using the gel-sol method. The study comprehensively investigated the surface morphology,crystal structure and electrochemical properties of LNMO before and after modification. The results indicate that the LYTP surface modification has a good multifunctional protective layer effect. It effectively reduces the dissolution of manganese in the electrolyte and improves the migration efficiency of lithium ions. The capacity retention of LNMO@LYTP remains high at 82% even after 500 cycles, which is significantly higher than that of the uncapped lithium nickel manganate cathode. The LNMO@LYTP has a discharge specific capacity of 116 mAh·g-1 even at 10C multiplication. This study contributes to the field of surface modification and provides ideas for further improving the electrochemical performance of other high-voltage manganese-based LIBs.