3D morphological analysis of copper foams as current collectors for Li-ion batteries by means of X-ray tomography

• X-ray tomography analysis of open-cell copper foams is performed.
• The effect of a dissolution treatment on the foam morphology is highlighted.
• The interest of such Cu foams as current collectors for Li-ion batteries is discussed.

As-received and chemically treated copper foams were characterized by means of laboratory X-ray tomography with a resolution of 0.5 μm. 3D image processing and analysis allowed the morphological parameters (size, sphericity, tortuosity etc.) of the pores and copper skeleton to be determined. The chemical dissolution of the Cu foam in an acid hydrogen peroxide solution results in an increase of the open pore size (from 54 to 93 μm) and a decrease of the foam thickness (from 140 to 115 μm). With an open porosity of 81.8% and a specific surface area as high as 280,000 (49,000) m2/m3 of Cu (foam), the chemically-treated Cu foam appears very attractive for use as a 3D current collector for metal (e.g. Si) based anodes for Li-ion batteries.