Rechargeable battery with resistive layer for enhanced safety
An improved high energy density rechargeable (HEDR) battery with an anode energy layer, a cathode energy layer, a separator between the anode and cathode energy layers for preventing internal discharge thereof, and at least one current collector for transferring electrons to and from either the anode or cathode energy layer, includes a resistive layer interposed between the separator and one of the current collectors for limiting the rate of internal discharge through the failed separator in the event of separator failure. The resistive layer has a fixed resistivity at temperatures between a preferred temperature range and an upper temperature safety limit for operating the battery. The resistive layer serves to avoid temperatures in excess of the upper temperature safety limit in the event of separator failure in the battery, and a fixed resistivity of the resistive layer is greater than the internal resistivity of either energy layer.
1. A battery, comprising:
a first electrode;
a second electrode;
a separator interposed between the first electrode and the second electrode, the separator configured to prevent an internal discharge;
at least one current collector coupled with the first electrode and/or the second electrode, the at least one current collector configured to transfer electrons; and
a resistive layer interposed between the separator and the at least one current collector, the resistive layer configured to prevent a temperature of the battery from exceeding a threshold by at least limiting a rate of internal discharge through the separator in response to an increase in the temperature of the battery, the resistive layer having a fixed resistivity at temperatures below the threshold, the fixed resistivity of the resistive layer being greater than the internal resistivity of each of the first electrode and the second electrode, and the fixed resistivity of the resistive layer remaining constant as the temperature of the battery increases.
2. The battery of claim 1 , wherein the resistive layer is porous and comprises:
a ceramic powder defining an interstitial space;
a binder for partially filling the interstitial space for binding the ceramic powder; and
a conductive component dispersed within the binder for imparting resistivity to the resistive layer, the interstitial space remaining partially unfilled for imparting porosity and permeability to the resistive layer.
3. The battery of claim 2 , wherein the resistive layer is compressed.
4. The battery of claim 2 , wherein the resistive layer comprises greater than 30% ceramic powder by weight.
5. The battery of claim 2 , wherein the resistive layer comprises greater than 50% ceramic powder by weight.
6. The battery of claim 2 , wherein the resistive layer comprises greater than 70% ceramic powder by weight.
7. The battery of claim 2 , wherein the resistive layer comprises greater than 75% ceramic powder by weight.
8. The battery of claim 2 , wherein the resistive layer comprises greater than 80% ceramic powder by weight.
9. The battery of claim 2 , wherein the resistive layer is permeable to transport of ionic charge carriers.
10. The battery of claim 1 , wherein the resistive layer is non-porous and has a composition comprising:
a non-conductive filler;
a binder for binding the non-conductive filler; and
a conductive component dispersed within the binder for imparting resistivity conductivity to the resistive layer.
11. The battery of claim 10 , wherein the resistive layer is impermeable to a transport of ionic charge carriers.
12. The battery of claim 1 , wherein the fixed resistivity of the resistive layer is at least twice as great as the internal resistivity of each of the first electrode and/or the second electrode.
13. The battery of claim 12 , wherein the fixed resistivity of the resistive layer is at least five times as great as the internal resistivity of each of the first electrode and/or the second electrode.
14. The battery of claim 12 , wherein the fixed resistivity of the resistive layer is at least ten times as great as the internal resistivity of each of the first electrode and/or the second electrode.
15. The battery of claim 1 , wherein the resistive layer lacks a physical phase transformation at temperatures between a preferred temperature range and the threshold for transforming the resistivity of the resistive layer.
16. The battery of claim 15 , wherein the resistive layer lacks a transformation from solid phase to non-solid phase for transforming the resistivity of the resistive layer from low resistivity to high resistivity at temperatures between a maximum operating temperature and the threshold.
17. The battery of claim 1 , wherein the resistive layer is non-sacrificial at temperatures below the threshold.
18. The battery of claim 17 , wherein the resistive layer is sacrificial at temperatures above the threshold.
19. The battery of claim 18 , wherein the resistive layer comprises a ceramic powder that chemically decomposes above the threshold for evolving a fire retardant gas.
20. The battery of claim 18 , wherein the resistive layer comprises a ceramic powder that chemically decomposes above the threshold for evolving a gas for delaminating the at least one current collector from the resistive layer.
21. The battery of claim 1 , wherein the first electrode comprises an anode, wherein the at least current collector comprises an anode current collector for transferring electrons to and/or from the anode, and wherein the resistive layer is interposed between the separator and the anode current collector.
22. The battery of claim 21 , wherein the resistive layer is interposed between the anode current collector and the anode.
23. The battery of claim 21 , wherein the resistive layer is interposed between the anode and the separator.
24. The battery of claim 21 , wherein the anode comprises:
a first anode energy layer; and
a second anode energy layer interposed between the first anode energy layer and the separator, wherein the resistive layer is interposed between the first anode energy layer and the second anode energy layer.
25. The battery of claim 1 , wherein the first electrode comprises a cathode, wherein the current collector comprises a cathode current collector for transferring electrons to and/or from the cathode, and wherein the resistive layer is interposed between the separator and the cathode current collector.
26. The battery of claim 25 , wherein the resistive layer is interposed between the cathode current collector and the cathode.
27. The battery of claim 25 , wherein the resistive layer is interposed between the cathode and the separator.
28. The battery of claim 25 , wherein the cathode comprises:
a first cathode energy layer; and
a second cathode energy layer interposed between the first cathode energy and the separator, wherein the resistive layer is interposed between the first cathode energy layer and the second cathode energy layer.
29. The battery of claim 1 , further comprising:
a first current collector for transferring electrons to and/or from the first electrode; and
a second current collector for transferring electrons to and/or from the second,
wherein the resistive layer comprises a first resistive layer and a second resistive layer, wherein the first resistive layer is interposed between the separator and the first current collector, and wherein the second resistive layer is interposed between the separator and the second current collector.
30. A method, comprising:
resisting, by a resistive layer of a battery, an internal discharge resulting from a failure of a separator of the battery, the resistive layer preventing a temperature of the battery from exceeding a threshold by at least limiting a rate of the internal discharge, the resistive layer being interposed between a separator and a current collector within the battery, the resistive layer having a fixed resistivity at temperatures below a threshold, the fixed resistivity of the resistive layer being greater than an internal resistivity of a first electrode of the battery and a second electrode of the battery, and the fixed resistivity of the resistive layer remaining constant as the temperature of the battery increases.