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Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique.

ABSTRACT: Electrochemical strain microscopy (ESM) is a powerful atomic force microscopy (AFM) mode for the investigation of ion dynamics and activities in energy storage materials. Here we compare the changes in commercial LiFePO₄ cathodes due to ageing and its influence on the measured ESM signal. Additionally, the ESM signal dynamics are analysed to generate characteristic time constants of the diffusion process, induced by a dc-voltage pulse, which changes the ionic concentration in the material volume under the AFM tip. The ageing of the cathode is found to be governed by a decrease of the electrochemical activity and the loss of available lithium for cycling, which can be stored in the cathode.

SUBMITTER: Simolka M

PROVIDER: S-EPMC7155899 | biostudies-literature | 2020

REPOSITORIES: biostudies-literature

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Comparison of fresh and aged lithium iron phosphate cathodes using a tailored electrochemical strain microscopy technique.

Simolka Matthias M Kaess Hanno H Friedrich Kaspar Andreas KA

Beilstein journal of nanotechnology 20200407

Electrochemical strain microscopy (ESM) is a powerful atomic force microscopy (AFM) mode for the investigation of ion dynamics and activities in energy storage materials. Here we compare the changes in commercial LiFePO<sub>4</sub> cathodes due to ageing and its influence on the measured ESM signal. Additionally, the ESM signal dynamics are analysed to generate characteristic time constants of the diffusion process, induced by a dc-voltage pulse, which changes the ionic concentration in the mate ...[more]

PMID: 32318319

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