Issue 36, 2019

Oriented porous LLZO 3D structures obtained by freeze casting for battery applications

Abstract

All solid-state lithium batteries are, potentially, higher energy density and safer alternatives to conventional lithium-ion batteries (LIBs). These are particularly attractive characteristics for large-scale applications such as electric vehicles and grid energy storage systems. However, the thin film deposition techniques used to make current devices are not readily scalable, and result in low areal capacities, which translate to low practical energy densities. To overcome these deficiencies, it is necessary to design thicker electrodes similar to what are used in LIBs (30–100 μm), in which the active material is composited with an ionic conductor and an electronically conducting additive, to overcome transport limitations. In this paper, we propose a method for making such an electrode, starting with a porous scaffold, i.e. Li7La3Zr2O12 (LLZO), made by freeze casting, which is then infiltrated with the active material LiNi0.6Mn0.2Co0.2O2 (NMC-622) and other components. The freeze casting technique results in the formation of oriented channels with low tortuosity, which run roughly parallel to the direction of the current. The scaffolds were characterized with synchrotron X-ray micro-tomography for structural analysis, as well as synchrotron X-ray fluorescence to map the elemental distribution in the infiltrated composite. A hybrid half-cell was constructed and cycled as proof of principle, and it showed good stability. In addition, a bilayer structure consisting of a porous layer combined with a dense LLZO film was successfully made as a prototype of an all solid-state battery. A mathematical model was established to propose optimized scaffold structures for battery performance.

Graphical abstract: Oriented porous LLZO 3D structures obtained by freeze casting for battery applications

Supplementary files

Article information

Article type
Paper
Submitted
18 jun. 2019
Accepted
19 ago. 2019
First published
20 ago. 2019

J. Mater. Chem. A, 2019,7, 20861-20870

Author version available

Oriented porous LLZO 3D structures obtained by freeze casting for battery applications

H. Shen, E. Yi, M. Amores, L. Cheng, N. Tamura, D. Y. Parkinson, G. Chen, K. Chen and M. Doeff, J. Mater. Chem. A, 2019, 7, 20861 DOI: 10.1039/C9TA06520B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements