Cathode insulator design

Patent metadata

Field	Value
Publication number	US-10629862-B2
Application number	US-201715803973-A
Country	US
Kind code	B2
Filing date	Nov 6, 2017
Priority date	Nov 4, 2016
Publication date	Apr 21, 2020
Grant date	Apr 21, 2020

Abstract

Disclosed herein are electrochemical cells that generally relate to the conversion of chemical energy to electrical energy. More particularly, the present disclosure is directed to primary lithium electrochemical cells possessing insulator pocket structures, which substantially envelope cathode components to prevent lithium cluster formation therein.

First claim

What is claimed is:

1. An electrochemical cell, comprising:
a) a casing comprising:
i) a container having a sidewall extending to an open end; and
ii) a lid closing the open end of the container, wherein a terminal pin extends through an opening in the lid, the terminal pin being in non-conductive relation with the lid;

b) an electrode assembly housed inside the casing, the electrode assembly comprising:
i) an anode comprising lithium supported on an anode current collector, wherein the anode current collector comprises at least one anode lead conductively connected to the casing;
ii) a cathode comprising a cathode active material supported on a cathode current collector, wherein the cathode current collector comprises a cathode tab extending outwardly beyond a perimeter edge of the cathode current collector, the perimeter edge from which the cathode tab extends being spaced closer to the lid than a remainder of the cathode current collector; and
iii) at least one separator positioned between the anode and the cathode to prevent direct physical contact between them;

c) an insulator compartment comprising:
i) a first insulator member having a first surrounding sidewall extending from a first major face wall to a first outer edge, the first major face wall being disposed adjacent to an inner surface of the lid with the first surrounding sidewall extending away from the lid toward the perimeter edge of the cathode current collector, wherein the terminal pin extends through a first opening in the first major face wall; and
ii) a second insulator member having a second surrounding sidewall extending from a second major face wall to a second outer edge, the second major face wall being disposed adjacent to the perimeter edge of the cathode current collector with the second surrounding sidewall extending away from the perimeter edge toward the lid, wherein the cathode tab extends through a second opening in the second major face wall,
iii) wherein the first and second insulator members are mated to each other with one of the first and second outer edges of the first and second surrounding sidewalls facing the other of the first and second major face walls so that at least a portion of the second surrounding sidewall is in an overlapping, direct contact relationship with at least a portion of the first surrounding sidewall to thereby form the insulator compartment residing between the perimeter edge and the lid, and
iv) wherein the terminal pin is connected to the cathode tab in the insulator compartment; and

d) an electrolyte provided in the casing to activate the electrode assembly.

2. The electrochemical cell of claim 1 , wherein the terminal pin is composed of molybdenum.

3. The electrochemical cell of claim 1 , wherein the insulator compartment defines a perimeter gap with respect to an inner surface of the container sidewall.

4. The electrochemical cell of claim 1 , wherein the electrode assembly further comprises at least two cathode plates, each cathode plate having a cathode tab conductively connected to the terminal pin inside the insulator compartment, and wherein at least a portion of the anode resides between the at least two cathode plates.

5. The electrochemical cell of claim 1 , wherein the anode has a serpentine shape with at least two pairs of cathode plates interleaved between respective folds of the serpentine anode, and wherein each pair of cathode plates has a cathode tab housed inside the insulator compartment where the cathode tabs corresponding to each of the at least two pairs of cathode plates are conductively connected to a cathode bridge, and wherein the cathode bridge is conductively connected to the terminal pin in the insulator compartment.

6. The electrochemical cell of claim 5 , wherein the second opening in the second major face wall of the second insulator member is configured to receive the cathode tabs and the cathode bridge and to further extend beyond an outer periphery of the cathode tabs and the cathode bridge to define an uncovered region of the electrode assembly.

7. The electrochemical cell of claim 1 , wherein one of the first outer edge of the first insulator member and the second outer edge of the second insulator member contacts the other of the first and second major face walls.

8. The electrochemical cell of claim 1 , wherein the electrode assembly has an uninsulated upper surface possessing a plurality of cavities.

9. The electrochemical cell of claim 1 , wherein the cathode active material is selected from the group consisting of silver vanadium oxide, copper silver vanadium oxide, V 2 O 5 , MnO 2 , LiCoO 2 , LiNiO 2 , LiMn 2 O 4 , TiS 2 , Cu 2 S, FeS, FeS 2 , Ag 2 O, Ag 2 O 2 , CuF 2 , Ag 2 CrO 4 , CF x , copper oxide, and copper vanadium oxide, and mixtures thereof.

10. The electrochemical cell of claim 1 , wherein a gap extends from an outer-most one of the first surrounding sidewall of the first insulator member and the second surrounding sidewall of the second insulator member to an inner surface of the container sidewall.

11. The electrochemical cell of claim 1 , wherein the terminal pin extending through the opening in the lid is supported in a ferrule by an electrically insulating material, the ferrule being electrically connected to the casing.

12. The electrochemical cell of claim 1 , wherein an inner portion of the terminal pin is received in a couple that is conductively connected to the cathode tab in the insulator compartment by a conductive ribbon.

13. The electrochemical cell of claim 1 , wherein the first and second insulator members are composed of a material that is impervious to lithium ion flow therethrough and which is selected from the group consisting of polyethylene, polyethylenechlorotrifluoroethylene, polypropylene, ETFE, and PTFE, and combinations thereof.

14. The electrochemical cell of claim 1 , further comprising an insulator bag at least partially enveloping the electrode assembly.

15. The electrochemical cell of claim 1 , wherein the casing is configured as a deep drawn casing structure.

16. The electrochemical cell of claim 1 , wherein the insulator compartment inhibits fluid flow communication of the electrolyte between the at least one anode lead conductively connected to the casing and the remainder of the electrode assembly.

17. The electrochemical cell of claim 1 being dischargeable without lithium precipitating from the electrolyte in an amount sufficient to permit internal loading of the electrochemical cell.

18. An electrochemical cell, comprising:
a) a casing comprising:
i) a container having a sidewall extending to an open end; and
ii) a lid closing the open end of the container, wherein a terminal pin extends through an opening in the lid, the terminal pin being in non-conductive relation with the lid;

b) an electrode assembly housed inside the casing, the electrode assembly comprising:
i) an anode comprising lithium supported on an anode current collector, wherein the anode current collector comprises at least one anode lead conductively connected to the casing;
ii) a cathode comprising a cathode active material supported on a cathode current collector, wherein the cathode current collector comprises a cathode tab extending outwardly beyond a perimeter edge of the cathode current collector, the perimeter edge from which the cathode tab extends being spaced closer to the lid than a remainder of the cathode current collector; and
iii) at least one separator positioned between the anode and the cathode to prevent direct physical contact between them;

c

Assignees

• Greatbatch Ltd

Inventors

• Roy Mark J
• Freitag Gary
• Lehnes Joseph M
• Dianetti David

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M2200/00

  Safety devices for primary or secondary batteries · CPC title

• H01M4/38

  of elements or alloys · CPC title

• H01M6/02

  Details (of electrodes H01M4/00; of non-active parts H01M50/00) · CPC title

• H01M4/382

  Lithium (H01M4/405 takes precedence) · CPC title