Rechargeable electrochemical cell
The present invention relates to a rechargeable electrochemical battery cell having a housing, a positive electrode, a negative electrode, and an electrolyte, the electrolyte containing sulfur dioxide and a conductive salt of the active metal of the cell. The total quantity of oxygen-containing compounds contained in the cell that are able to react with the sulfur dioxide, reducing the sulfur dioxide, is not more than 10 mMol per Ah theoretical capacitance of the cell.
1. Rechargeable electrochemical battery cell, comprising:
a housing,
a positive electrode,
a negative electrode,
an active metal,
an electrolyte which contains sulfur dioxide and a conductive salt of the active metal, and
a total quantity of oxygen contained in compounds which are able to react with sulfur dioxide in a reaction by which the sulfur dioxide is reduced of not more than 10 mMol per Ah theoretical charge capacitance of the rechargeable electrochemical battery cell, wherein the compounds which are able to react with sulfur dioxide are on each or in each of the positive electrode, the negative electrode, and the electrolyte.
2. The rechargeable electrochemical battery cell according to claim 1 , wherein the total quantity of oxygen in the cell that is contained in compounds which are able to react with the sulfur dioxide in a reaction by which the sulfur dioxide is reduced, is not more than 0.1 mMol per Ah theoretical charge capacitance of the cell.
3. The battery cell according to claim 1 , wherein, as the reaction product of the reaction by which the sulfur is reduced, a sulfur-oxygen compound is formed in which the sulfur has an oxidation level not exceeding +III.
4. The battery cell according to claim 1 , wherein, as the reaction product of the reaction by which the sulfur is reduced, a sulfur-oxygen compound is formed, which compound additionally contains a halogen and in which compound the oxidation level of the sulfur is +VI.
5. The battery cell according to claim 1 , wherein the electrolyte contains at least 1 mMol sulphur dioxide per Ah theoretical charge capacitance of the cell.
6. The battery cell according to claim 1 , wherein the electrolyte contains at least 10 mMol sulfur dioxide per Ah theoretical charge capacitance of the cell.
7. The battery cell according to claim 1 , wherein the active metal is selected from the group consisting of the alkali metals, alkaline earth metals, and metals of the second subgroup of the periodic system.
8. The battery cell according to claim 7 , wherein the active metal is lithium, sodium, calcium, zinc, or aluminum.
9. The battery cell according to claim 1 , wherein the negative electrode is an insertion electrode.
10. The battery cell according to claim 9 , wherein the negative electrode contains carbon.
11. The battery cell according to claim 1 , wherein the positive electrode contains a metal oxide or a metal halide or a metal phosphate.
12. The battery cell according to claim 11 , wherein the positive electrode contains an intercalation compound.
13. The battery cell according to claim 1 , wherein the electrolyte contains, as the conductive salt, a halide, an oxalate, a borate, a phosphate, an arsenate, or a gallate of the active metal.
14. The battery cell according to claim 1 , wherein the concentration of conductive salt in the electrolyte is at least 0.01 mol/l.
15. The battery cell according to claim 1 , wherein the concentration of conductive salt in the electrolyte is at least 5 mol/l.
16. The battery cell according to claim 1 , wherein the quantity of electrolyte, per Ah theoretical charge capacitance of the cell, is not more than 50 ml.
17. The battery cell according to claim 1 , wherein the quantity of electrolyte, per Ah theoretical charge capacitance of the cell, is not more than 10 ml.
18. The battery cell according to claim 1 , wherein it contains a separator that separates the negative and positive electrodes from one another, and prevents metallic lithium deposited at the negative electrode from penetrating to the surface of the positive electrode.
19. The battery cell according to claim 1 , wherein it contains an isolator that separates the negative and positive electrodes from one another electrically, the isolator being formed and arranged in such a manner that active metal deposited on the negative electrode during charging of the cell may contact the positive electrode in such a manner that locally limited short-circuit reactions occur at the surface of the positive electrode.
20. The rechargeable electrochemical battery cell according to claim 1 , wherein the total quantity of oxygen in the cell that is contained in compounds which are able to react with the sulfur dioxide in a reaction by which the sulfur dioxide is reduced, is not more than 5 mMol per Ah theoretical charge capacitance of the cell.
21. The rechargeable electrochemical battery cell according to claim 1 , wherein the total quantity of oxygen in the cell that is contained in compounds which are able to react with the sulfur dioxide in a reaction by which the sulfur dioxide is reduced, is not more than 1 mMol per Ah theoretical charge capacitance of the cell.
22. The rechargeable electrochemical battery cell according to claim 1 , wherein the total quantity of oxygen in the cell that is contained in compounds which are able to react with the sulfur dioxide in a reaction by which the sulfur dioxide is reduced, is not more than 0.5 mMol per Ah theoretical charge capacitance of the cell.
23. Battery cell according to claim 1 , wherein the quantity of oxygen in the negative electrode that is contained in compounds which are able to react with the sulfur dioxide in a reaction by which the sulfur dioxide is reduced, is not more than 6 mMol per Ah theoretical charge capacitance of the cell.
24. Battery cell according to claim 1 , wherein the quantity of oxygen in the positive electrode that is contained in compounds which are able to react with the sulfur dioxide in a reaction by which the sulfur dioxide is reduced, is not more than 8 mMol per Ah theoretical charge capacitance of the cell.
25. Battery cell according to claim 1 , wherein the quantity of oxygen in the electrolyte that is contained in compounds which are able to react with the sulfur dioxide in a reaction by which the sulfur dioxide is reduced, is not more than 10 mMol per Ah theoretical charge capacitance of the cell.
26. Battery cell according to claim 1 , wherein the electrolyte contains at least 5 mMol sulphur dioxide per Ah theoretical charge capacitance of the cell.
27. Battery cell according to claim 1 , wherein the concentration of conductive salt in the electrolyte is at least 0.1 mol/l.
28. Battery cell according to claim 1 , wherein the concentration of conductive salt in the electrolyte is at least 1 mol/l.
29. Battery cell according to claim 1 , wherein the quantity of electrolyte, per Ah theoretical charge capacitance of the cell, is not more than 20 ml.