3D printing of ultrathick natural graphite anodes for high-performance interdigitated three-dimensional lithium-ion batteries

Graphite has been the major anode material of choice for lithium-ion batteries (LIBs) for over 30 years. This study reports three-dimensional (3D) printing of comb-like 3D natural graphite (NG) electrodes for high-performance interdigitated 3D LIBs. Printable NG inks were developed and 3D NG electrodes with the thickness of 347.3 μm, 581.7 μm and 786.7 μm (corresponding areal mass loading: 16.3 mg cm−2, 24.4 mg cm−2 and 32.9 mg cm−2) were fabricated via a low temperature direct write 3D printing technology. The 3D-printed electrodes had tri-modally hierarchical porous microstructures with a high porosity of 54.84%. In addition, these thick electrodes showed excellent electrochemical performance with an impressive areal capacity of 13.68 mAh cm−2 @ 0.1C for electrodes with the thickness of 786.7 μm. With this type of 3D electrodes, the capacity fade over the increase of discharge rates was greatly reduced in comparison with tape casted electrodes with the same electrode thickness. This study demonstrates the potential of 3D-printed NG electrodes for high-performance LIBs.