High-performance lithium–selenium batteries enabled by nitrogen-doped porous carbon from peanut meal

Biomass-derived porous carbon displays a great potential for lithium–selenium (Li–Se) batteries owing to its green resource and inherent structural advantages, which can effectively restrict the shuttle effect of Se cathode. Peanut meal, by-product of the extraction of peanut oil, is a promising precursor for N-doped porous carbon. However, peanut meal is difficult to be activated in solution due to its high hydrophobicity. Thus, non-reports have been available for peanut meal-derived porous carbon used as Li–Se battery cathode host. In this work, we have innovatively proposed a very simple method of activating peanut meal by directly physically grinding the activator with the peanut meal and then annealing it to convert it into nitrogen-doped three-dimensional porous carbon (N-PC) with rich nanoscale pore size structures, which is then used as the Se host for Li–Se batteries. The N-PC shows a high specific surface area of 938.872 m2 g−1. The Se/N-PC composite cathode delivers a specific capacity of 461.4 mA h g−1 for 250 cycles at 0.2 C, corresponding to a high-capacity retention of 97.2%. Moreover, the Se/N-PC composite maintains a high capacity over 340.1 mA h g−1 after 1,000 cycles at a high current density of 2 C. Our work effectively resolves the hydrophobic biomass activation problem and manufactures abundant and low-cost Se host for Li–Se batteries.