Rechargeable battery cell with active electrode depolarizer
Rechargeable battery cells are provided in which electrolyte comprises SO 2 and a conductive salt, wherein upon discharge a reaction product is produced at the positive electrode. The rechargeable battery cells can comprise carbon and a conducting element having a three-dimensional porous metal structure, and can include optional components such as a metal oxide that catalyzes at least one reduction reaction at the cathode upon discharge and/or a metal halide. Methods of making and using such rechargeable battery cells are provided.
1. A rechargeable lithium-ion battery cell, comprising:
a gas-tight housing;
at least one positive electrode comprising a porous metal structure with carbon incorporated therein, wherein the positive electrode has a thickness of at least 0.2 mm and the porous metal structure comprises at least 50% of the thickness of the positive electrode, wherein the specific surface area of the carbon used to fabricate the positive electrode is at least 200 m 2 /g, and wherein the porosity of the positive electrode is at least 50%;
at least one negative electrode; and
an electrolyte comprising SO 2 and a conductive salt;
wherein the SO 2 in the electrolyte serves as an active electrode depolarizer.
2. The rechargeable battery cell of claim 1 , wherein the positive electrode comprises at least one further component that catalyzes at least one reduction reaction at the cathode upon discharge.
3. The rechargeable battery cell according to claim 1 , wherein the positive electrode comprises a metal oxide that catalyzes at least one reduction reaction at the cathode upon discharge, and wherein the metal oxide comprises a metal selected from the group consisting of vanadium, nickel, copper, magnesium, manganese, titanium, aluminum, lead, palladium, tungsten, chromium, and combinations thereof.
4. The rechargeable battery cell according to claim 3 , wherein metal oxide is present in an amount of from 1 to 20% by weight of the weight of the carbon in electrode.
5. The rechargeable battery cell according to claim 1 , wherein the electrolyte comprises a conductive salt of an alkali metal or an alkaline earth metal selected from the group consisting of an aluminate, a halide, an oxalate, a borate, a phosphate, an arsenate, a gallate, and combinations of two or more of the foregoing.
6. The rechargeable battery cell according to claim 5 , wherein the conductive salt is a lithium tetrahaloaluminate.
7. The rechargeable battery cell according to claim 1 , wherein the electrolyte comprises a concentration of SO 2 per mole of conductive salt selected from the group consisting of from 0.5 to 20 mol SO 2 per mol conductive salt, from 0.5 to 8.0 mol SO 2 per mol conductive salt, from 1.0 to 6.0 mol SO 2 per mol conductive salt, from 1.0 to 5.0 mol SO 2 per mol conductive salt, from 1.5 to 5.0 mol SO 2 per mol conductive salt, from 2.0 mol to 5.0 mol SO 2 per mol conductive salt, from 2.0 to 4.0 mol SO 2 per mol conductive salt, 1.5 to 2.5 mol SO 2 per mol conductive salt, 1.75 to 2.25 mol SO 2 per mol conductive salt, 2.0 to 3.0 mol SO 2 per mol conductive salt, and about 2.0 mol SO 2 per mol conductive salt.