Oxygen-consuming battery with improved high rate capability
View Patent ↗An oxygen-consuming battery, such as a metal-air cell or fuel cell battery using oxygen from outside the battery as an active material, and having an improved high rate capability is disclosed. After the battery has been put into use, a light sacrificial drain is placed on the battery during periods when the battery is not being used to provide power in order to reduce degradation in rate capability that can occur over time, particularly when the battery is being used intermittently. Also disclosed is a combination of the oxygen-consuming battery and an electronic device that can be powered by the battery.
1. A battery for providing power to operate an electronic device comprising one or more metal-air cells, the one or more metal air cells comprising a housing with one or more oxygen entry ports, an first, oxygen consuming, electrode disposed in the housing, a second, counter, electrode disposed in the housing, an electrolyte disposed in the housing, a first electrical contact terminal in electrical contact with the first electrode, and a second electrical contact terminal in electrical contact with the second electrode; wherein:
oxygen from outside the housing enters the housing to reach the oxygen consuming electrode;
when the battery is ready for use and not providing power to operate the electronic device, an electrical circuit is complete between the first and second terminals of at least one of the metal-air cells; and
the electrical circuit comprises a sacrificial drain on the at least one of the metal-air cells.
2. The battery as defined by claim 1 , wherein the electrolyte is an aqueous alkaline electrolyte.
3. The battery as defined by claim 2 , wherein the electrolyte comprises potassium hydroxide.
4. The battery as defined by claim 1 , wherein the oxygen from outside the housing is contained in atmospheric air from outside the housing and contains at least 0.05 volume percent carbon dioxide, based on the volume of the oxygen at 15° C. and a pressure of 101,325 Pa.
5. The battery as defined by claim 1 , wherein the rate of oxygen able to enter the housing is further restricted to less than the rate of oxygen able to enter the housing with the air entry ports unrestricted.
6. The battery as defined by claim 1 , wherein the sacrificial drain is also present when the battery is providing power to operate the device.
7. A combination of the battery as defined by claim 1 and the electronic device that can be powered by the battery.
8. The combination of the battery and the electronic device as defined by claim 7 , wherein the electrical circuit comprising the sacrificial drain is a part of the battery.
9. The combination of the battery and the electronic device as defined by claim 7 , wherein the electrical circuit comprising the sacrificial drain is a part of the device.
10. The combination of the battery and the electronic device as defined by claim 7 , wherein the electrical circuit comprising the sacrificial drain can be opened and closed.
11. The combination of the battery and the electronic device as defined by claim 10 , wherein the electrical circuit comprising the sacrificial drain can be opened and closed by manually operating a switch.
12. The combination of the battery and the electronic device as defined by claim 11 , wherein the switch is used to turn the device on and off.
13. The combination of the battery and the electronic device as defined by claim 10 , wherein the electrical circuit comprising the sacrificial drain can be opened and closed electronically.
14. The combination of the battery and the electronic device as defined by claim 13 , wherein the electrical circuit comprising the sacrificial drain can be opened and closed by a control circuit.
15. The combination of the battery and the electronic device as defined by claim 14 , wherein the control circuit determines a device mode.