Small hollow nanostructures as a new morphology to improve stability of LiMn 2 O 4 cathodes in Li-ion batteries

RADA, EVILUS; LIMA, ENIO; RUIZ, FABRICIO; MORENO, SERGIO

NANOTECHNOLOGY

IOP PUBLISHING LTD

Año: 2021 vol. 32

0957-4484

Spinel LiMn2O4 is a promising cathode material for lithium-ion batteries. However, bulkLiMn2O4 commonly suffers from capacity fading due to the dissolution of Mn into theelectrolyte during cycling. Moreover, bulk LiMn2O4 exhibits a low Li+ diffusion coefficient thatlimits the volume available to Li+ storage. Herein, we report the synthesis of small hollowporous LiMn2O4 nanostructures with a mean size of 51 nm exhibiting exposed (111) planes,assembled by nanoparticles of about 6 nm in size. The morphological features of thesenanostructures ensure a large contact area between the material and the electrolyte, shorten thepathways for Li+ diffusion and provide effective accommodation of the volume change duringcycling. Therefore, these hollow nanostructures exhibit improved discharge capacity retention(nearly 82% after 200 cycles) and a greater Li+ diffusion coefficient (3.46 × 10−7 cm s−1)compared with that of bulk LiMn2O4.