3D porous hierarchical Li2FeSiO4/C for rechargeable lithium batteries

Lithium iron silicates (Li2FeSiO4) are promising cathodes for rechargeable lithium batteries owing to their high capacity, low cost, and superior stability. However, Li2FeSiO4 suffers from extremely low electronic and ionic conductivity. Herein, we used a two-step method to fabricate carbon-painted, three-dimensional (3D) porous hierarchical Li2FeSiO4 (3D Li2FeSiO4/C) as an efficient cathode, based on a facile hydrothermal reaction followed by carbon nanopainting. The hierarchical porous structure endows the Li2FeSiO4/C with efficient electrolyte storage and penetration, whereas the 3D carbon nanopainting provides an expressway for rapid electron transport. As a result, this 3D Li2FeSiO4/C exhibits a high electrochemical activity towards Li cycling, outperforming its counterpart without carbon painting and other Li2FeSiO4 materials. This research highlights the potential of engineering 3D porous structure to circumvent the poor conductivity in battery materials.