Operando SANS investigation of the sodium-ion pore-filling mechanism of in hard carbon anode in sodium-ion batteries

In this proposed work, we aim to study the pore-filling behaviour in high-performance hard carbon via operando SANS using modified single-layer pouch cells, aiming to provide representative evidence of the hard carbon in real-world applications throughout the plateau region, as well as the storage mechanism in the sloping regions. We will investigate the discharging/sodiation process and the under-reported charging/desodiation process (i.e., removal of the Na cluster from pores) during charging. More specifically, the SANS data will be analysed to get some information about the pore size, geometry, pore size distribution, SLD to attempt to quantify levels of sodiation. These significant insights will provide direct evidence for (or against) the pore-filling mechanisms. We expect to be able to provide clear instructions on the porosity design for hard carbon as an anode for Na-ion storage and be able to compare these results meaningfully with those of other hard carbon. Hard carbon design is quite varied and challenging to get right to justify this argument.