All-solid-state lithium-sulfur (Li-S) batteries offer the possibility of high theoretical energy densities and long cycle lifetime. Finding new multiporous insulating materials or wide bandgap semiconductors suitable for the transportation of Li-ions is a key problem for the application of solid state lithium-sulfur (Li-S) batteries. In this study, an sp2-hybridized multiporous boron nitride (d-BN) is found to be able to be used as a solid electrolyte or filter in Li-S batteries due to the lower energy barriers of Li-ion diffusion along its [110] direction. By means of density functional theory (DFT) calculations, it is also found that the d-BN is more stable than most reported BN polymorphs. In addition, the elastic properties, ideal tensile strength, electronic structure, lattice thermal conductivity and phonon lifetime of d-BN are also investigated.