Primary alkaline battery containing bismuth metal oxide
View Patent ↗Primary alkaline batteries containing pentavalent bismuth metal oxides are disclosed.
1. A primary battery, comprising:
a cathode comprising particles consisting essentially of electrochemically active bismuth oxide in which at least 50 atomic percent of the bismuth in the bismuth oxide is pentavalent bismuth and, optionally, an electrically conductive coating, the particles having a mean particle size of from about 0.005 to 50 microns and a specific surface area from about 1 to 40 m 2 /g;
an anode;
a separator between the cathode and the anode; and
an alkaline electrolyte comprising an aqueous alkali metal hydroxide solution.
2. The battery of claim 1 , wherein the cathode further comprises a second electrochemically active material.
3. The battery of claim 2 , wherein the second electrochemically active material is selected from the group consisting of manganese dioxide, nickel oxyhydroxide, silver oxide, silver nickelate, silver copper oxide, silver permanganate, barium permanganate, barium manganate, and barium ferrate.
4. The battery of claim 2 , wherein the second electrochemically active material has a mean particle size of from about 1 micron to 100 microns.
5. The battery of claim 2 , wherein the second electrochemically active material has a specific surface area of from about 3 to 50 m 2 /g.
6. The battery of claim 1 , wherein the electrochemically active oxide comprises an alkali metal.
7. The battery of claim 1 , wherein the electrochemically active oxide comprises an alkaline earth metal.
8. The battery of claim 1 , wherein the electrochemically active oxide comprises a transition metal.
9. The battery of claim 1 , wherein the electrochemically active oxide comprises a main group metal.
10. The battery of claim 1 , wherein the particles have a mean particle size of from about 0.1 to 15 microns.
11. The battery of claim 1 , wherein at least 70% atomic percent of the bismuth in the bismuth oxide is pentavalent bismuth.
12. The battery of claim 1 , wherein at least 90% atomic percent of the bismuth in the bismuth oxide is pentavalent bismuth.
13. The battery of claim 1 , wherein the bismuth oxide also contains trivalent bismuth.
14. The battery of claim 1 , wherein the particles include the electrically conductive coating and the coating comprises a carbonaceous material.
15. The battery of claim 1 , wherein the particles include the electrically conductive coating and the coating comprises metal.
16. The battery of claim 1 , wherein the particles consist of the bismuth oxide and, optionally, the electrically conductive coating.