Lithium battery having a protected lithium electrode and an ionic liquid catholyte
Active metal and active metal intercalation electrode structures and battery cells having ionically conductive protective architecture including an active metal (e.g., lithium) conductive impervious layer separated from the electrode (anode) by a porous separator impregnated with a non-aqueous electrolyte (anolyte). This protective architecture prevents the active metal from deleterious reaction with the environment on the other (cathode) side of the impervious layer, which may include aqueous or non-aqueous liquid electrolytes (catholytes) and/or a variety of electrochemically active materials, including liquid, solid and gaseous oxidizers. Safety additives and designs that facilitate manufacture are also provided.
1. An electrochemical cell structure, comprising:
a cathode structure comprising a catholyte, the catholyte comprising an ionic liquid; and
a protected anode structure comprising,
an anode comprising a material selected from the group consisting of an active metal, active metal ion, active metal alloy, active metal alloying metal and active metal intercalating material, and
an ionically conductive protective architecture on a first surface of the anode, the architecture comprising a substantially impervious ionically conductive layer that protects the anode from contact with catholyte.
2. The electrochemical cell of claim 1 wherein the ionic liquid has a melting point below 100° C.
3. The electrochemical cell of claim 1 wherein the ionic liquid is selected from the group consisting of imidazolium derivatives, pyridinium derivatives, phosphonium compounds, and tetralkylammonium compounds.
4. The electrochemical cell of claim 1 wherein the ionic liquid is selected from the group consisting of 1-Ethyl-3-methylimidazolium tosylate (EMIM-Ts), 1-Butyl-3-methylimidazolium octyl sulfate (BMIM-OctSO 4 ), 1-Ethyl-3-methylimidazolium hexafluorophosphate, and 1-Hexyl-3-methylimidazolium tetrafluoroborate.
5. The electrochemical cell of claim 1 , wherein the active metal of the anode material is lithium.
6. The electrochemical cell of claim 1 , wherein the anode material is lithium metal.
7. The electrochemical cell of claim 1 , wherein the anode material is an active metal intercalating material comprising carbon.
8. The electrochemical cell of claim 7 , wherein the active metal intercalating material is carbon.
9. The electrochemical cell of claim 1 , wherein the cell is a lithium ion cell.
10. The electrochemical cell of claim 9 , wherein the cathode structure further comprises a lithium metal oxide cathode.
11. The electrochemical cell of claim 10 , wherein the metal oxide is selected from the group consisting of CoO 2 , NiO 2 , Mn 2 O 4 and FePO 4 .