abstract |
One embodiment of the invention is an alkali metal-selenium battery comprising an anode, a selenium cathode, an electrolyte, an electronically insulating porous separator, and an electronically conducting graphene separator layer comprising a solid graphene foam, paper or fabric that is permeable to lithium ions or sodium ions but is substantially non-permeable to selenium or metal selenide, wherein the graphene separator layer is disposed between the selenium cathode layer and the electronically insulating porous separator layer and the graphene separator layer contains pristine graphene sheets or non-pristine graphene sheets having 0.01% to 20% by weight of non-carbon elements, wherein the non-pristine graphene is selected from graphene oxide, reduced graphene oxide, graphene fluoride, graphene chloride, graphene bromide, graphene iodide, hydrogenated graphene, nitrogenated graphene, boron-doped graphene, nitrogen-doped graphene, chemically functionalized graphene, or a combination thereof. |