Correlative full field X-ray compton scattering imaging and X-ray computed tomography for in situ observation of Li ion batteries
Chu Lun Alex Leung, Matthew D. Wilson, Thomas Connolley, Stephen P. Collins, Oxana V. Magdysyuk, Matthieu Boone, Kosuke Suzuki, Matthew C. Veale, Enzo Liotti, Frederic Van Assche, Andrew Lui, Chun Huang
Abstract
Increasing electrode thickness is gaining more attention as a potential route to increase energy density for Li ion batteries although the realizable capacity and rate capability are usually limited by Li+ ion diffusion during (dis)charge, especially at increased (dis)charge rates. It remains challenging to visualize and quantify the low atomic number Li+ chemical stoichiometry distribution inside the electrode within commercially standard battery geometry, e.g. coin cells with stainless steel casings. Here, we map the distribution of Li + chemical stoichiometry in the electrode microstructure inside a working coin cell battery to show the amount of electrode materials contributing to energy storage performance using innovative in situ correlative full-field X-ray Compton scattering imaging (XCS-I) and X-ray computed tomography (XCT). We design and fabricate an ultra-thick (∼1 mm) cathode of LiNi0.8Mn0.1Co0.1O2 with a microstructure containing vertically oriented pore arrays using a directional ice templating method. This novel technique paves a new way to map low atomic number elements in 3D structures and study how the microstructure improves Li + ion diffusivity and energy storage performance.