Carbon nanotubes (CNTs) are attractive additives for battery electrodes because of their excellent electrical and thermal conductivity. However, these properties typically degrade by an order of magnitude in assemblies of CNTs compared to the properties measured in individual CNTs. This discrepancy can be bridged by aligning CNTs into yarns, sheets, or vertically aligned forests. In our work, we study aligned CNTs organized in micro-scale honeycomb structures which are desirable due to their mechanical robustness, conductivity, and high surface area. Because of their mechanical robustness, their surface chemistry can be modified to design battery electrodes.

 Here we focus on developing Li-ion battery anodes with a well-defined honeycomb morphology. These honeycombs are fabricated using chemical vapour deposition of CNTs from lithographically patterned catalyst particles. The grown CNTs are subsequently compacted using an elasto-capillary self-aggregation process and thus shaped into honeycomb patterns with varying cell diameters. These electrodes are tested and compared against unaligned CNT powders decorated with the same active nanoparticles, i.e. Iron(III)-Oxide (Fe₂O₃). The influence of the cell sizes and aspect ratios on the electrode performance is measured after the decoration with Fe₂O₃ as an active material.