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arXiv · 2211.08060

Exploring the nanoscale origin of performance enhancement in Li$_{1.1}$Ni$_{0.35}$Mn$_{0.55}$O$_2$ batteries due to chemical doping

Thomas Thersleff·Jordi Jacas Biendicho·Kunkanadu Prakasha·Elias Martinez Moreno·Leif Olav Jøsang·Jekabs Grins·Aleksander Jaworski·Gunnar Svensson
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Abstract

Despite significant potential as energy storage materials for electric vehicles due to their combination of high energy density per unit cost and reduced environmental and ethical concerns, Co-free lithium ion batteries based off layered Mn oxides presently lack the longevity and stability of their Co-containing counterparts. Here, we demonstrate a reduction in this performance gap via chemical doping, with Li$_{1.1}$Ni$_{0.35}$Mn$_{0.55}$O$_2$ achieving an initial discharge capacity of 159 mAhg$^{-1}$ at C/3 rate and a corresponding capacity retention of 94.3% after 150 cycles. We subsequently explore the nanoscale origins of this improvement through a combination of advanced diffraction, spectroscopy, and electron microscopy techniques, finding that optimized doping profiles lead to an improved structural and chemical compatibility between the two constituent sub-phases that characterize the layered Mn oxide system, resulting in the formation of unobstructed lithium ion pathways between them. We also directly observe a structural stabilization effect of the host compound near the surface using aberration corrected scanning transmission electron microscopy and integrated differential phase contrast imaging.

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Thomas Thersleff, Jordi Jacas Biendicho, Kunkanadu Prakasha, Elias Martinez Moreno, Leif Olav Jøsang, Jekabs Grins, Aleksander Jaworski, Gunnar Svensson. 2022-11-15. Exploring the nanoscale origin of performance enhancement in Li$_{1.1}$Ni$_{0.35}$Mn$_{0.55}$O$_2$ batteries due to chemical doping. https://doi.org/10.1002/aenm.202203889

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