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DOE OSTI · 1725768

Kinetic Limitations in Single-Crystal High-Nickel Cathodes

Wang, Feng·Ge, Mingyuan·Wi, Sungun·Liu, Xiang·Bai, Jianming·Ehrlich, Steven·Lu, Deyu·Lee, Wah-Keat·Chen, Zonghai
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Abstract

High-nickel cathodes attract immense interest for use in lithium-ion batteries, to boost Li-storage capacity while reducing cost. For overcoming the intergranular-cracking issue in polycrystals, single-crystals are considered an appealing alternative, but aggravating concerns on compromising the electrochemical kinetics of electrodes. We report here a quantitative assessment of electrochemical reaction in single-crystal LiNi 0.8 Mn 0.1 Co 0.8 O 2 using operando hard X-ray microscopy/spectroscopy, revealing a strong dependence of redox kinetics on the state of charge (SOC) - being sluggish at low SOC while increasing rapidly as SOC increases both in the bulk electrode and individual particles. The observation is corroborated by transport measurements and finite-element simulation, indicating that the sluggish kinetics in single-crystals is governed by ionic transport at low SOC and may be alleviated through synergistic interaction with polycrystals integrated into a same electrode. Finally, with the elucidated mechanistic origin and alleviation solution of kinetic limitations in single-crystal high-Ni cathodes, this work constitutes a step forward in enabling their practical deployment.

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25 ENERGY STORAGEHigh-Nickel cathodesX-ray spectromicroscopyhigh-nickel cathodeskinetic limitationslithium-ion batteriessingle crystalsingle crystalsx-ray spectromiscroscopy

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Wang, Feng, Ge, Mingyuan, Wi, Sungun, Liu, Xiang, Bai, Jianming, Ehrlich, Steven, Lu, Deyu, Lee, Wah-Keat, Chen, Zonghai. 2020-11-20. Kinetic Limitations in Single-Crystal High-Nickel Cathodes. https://doi.org/10.1002/anie.202012773

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