Since their introduction, lithium ion batteries (LIBs) have become ubiquitous for powering portable electronic devices. However, the charging rate of graphite (by far the most common anode material) is limited by lithium diffusion into the material.

A critical issue of LIBs technology is the low theoretical specific capacity of conventional graphite anodes, limited to 372 mAh/g¹. For this reason, a large fraction of current research is focusing on alternative anode materials

Thus, surface engineering of carbon particles (active material design) and modification of carbon electrode structure (electrode design) are necessary to alleviate these critical limiting factors. Herein, we are providing a novel synthetic approach to obtain N-doped carbon nanotubes (N-CNTs) starting from the synthesis of polypyrrole nanotubes (PPy-NTs) followed by pyrolysis. This approach leads to materials and electrodes with the highly porous nature of PPy-NTs and great graphitic texture with copious heteroatom functionalities².

The N-CNTs were used as the negative electrode coupled with a positive C-LFP (C-coated LiFePO₄) with a fractal granularity, prepared in our lab through an eco-friendly water-based synthesis, resulting in a hybrid device with good electrochemical properties.

References

1.            Scrosati, B. & Garche, J. Lithium batteries: Status, prospects and future. Journal of Power Sources 195, 2419-2430 (2010).

2.            Dubal, D.P. et al. Synthetic approach from polypyrrole nanotubes to nitrogen doped pyrolyzed carbon nanotubes for asymmetric supercapacitors. Journal of Power Sources 308, 158-165 (2016).