Sealing assembly, lithium ion battery comprises the same, and method for preparing sealing assembly

1. A sealing assembly for a battery, comprising:

a ceramic ring having a receiving hole, wherein the ceramic ring is selected from a group consisting of alumina ceramic ring, zirconia ceramic ring, aluminum nitride ceramic ring, boron nitride ceramic ring, silicon nitride ceramic ring, and alumina-zirconia composite ceramic ring;

a metal ring fitted over the ceramic ring for sealing an open end of the battery,

a column formed in the receiving hole which comprises a metal-metal composite,

wherein the metal-metal composite comprises:

a metal porous body, wherein the metal porous body comprises a first metal and a second metal, and the first metal is Cu; the second metal is at least one selected from a group consisting of W and Mo; and

a metal material filled in pores of the metal porous body, wherein the metal material is Cu,

wherein the expansion coefficient of the metal-metal composite is regulated to be approximate to the expansion coefficient of the ceramic ring.

2. The sealing assembly for a battery according to claim 1 , wherein the metal material is filled in the pores of the metal porous body by means of melt infiltration.

3. The sealing assembly for a battery according to claim 1 , wherein based on the total weight of the metal porous body, the content of the first metal is about 5 wt % to about 40 wt %, and the content of the second metal is about 60 wt % to about 95 wt %.

4. The sealing assembly for a battery according to claim 1 , wherein the metal porous body comprises Cu and Mo, and based on the total weight of the metal porous body, the content of Cu is about 10 wt % to about 40 wt %, the content of Mo is about 60 wt % to about 90 wt %.

5. The sealing assembly for a battery according to claim 1 , wherein the metal porous body comprises Cu and W, and based on the total weight of the metal porous body, the content of Cu is about 5 wt % to about 20 wt %; the content of W is about 80 wt % to about 95 wt %.

6. The sealing assembly for a battery according to claim 1 , wherein the weight ratio of the metal material to the metal porous body is about (1 to 2):(1 to 19).

7. The sealing assembly for a battery according to claim 1 , wherein the sealing assembly is configured as a sealing assembly for a negative pole of the battery.

8. A method for fabricating a sealing assembly of a battery, comprising:

providing a ceramic ring having a receiving hole, wherein the ceramic ring is selected from a group consisting of alumina ceramic ring, zirconia ceramic ring, aluminum nitride ceramic ring, boron nitride ceramic ring, silicon nitride ceramic ring, and alumina-zirconia composite ceramic ring;

filing a mixture comprising a first metal and a second metal into the receiving hole of the ceramic ring, and sintering the mixture to obtain a metal porous body, wherein the first metal is Cu, the second metal is at least one selected from a group consisting of W and Mo;

filing a metal material into the receiving hole of the ceramic ring and above the sintered metal porous body, treating the metal material at a temperature above a melting point of the metal material to allow the melted metal material to infiltrate into the metal porous body, and obtaining a metal-metal composite after cooling, wherein the metal material is Cu; and

welding a metal ring to the ceramic ring so as to fit the metal ring over the ceramic ring,

wherein the expansion coefficient of the metal-metal composite is regulated to be approximate to the expansion coefficient of the ceramic ring.

9. The method according to claim 8 , wherein based on the total weight of the metal porous body, the content of the first metal is about 5 wt % to about 40 wt %, and the content of the second metal is about 60 wt % to about 95 wt %.

10. The method according to claim 9 , wherein the first metal is Cu, and the second metal is Mo, and based on the total weight of the metal porous body, the content of Cu is about 10 wt % to about 40 wt %, the content of Mo is about 60 wt % to about 90 wt %.

11. The method according to claim 9 , wherein the first metal is Cu, and the second metal is W, and based on the total weight of the metal porous body, the content of Cu is about 5 wt % to about 20 wt %, the content of W is about 80 wt % to about 95 wt %.

12. The method according to claim 8 , wherein the weight ratio of the metal material to the metal porous body is about (1 to 2):(1 to 19).

13. The method of claim 8 , wherein the first metal and the second metal is sintered at the same time to obtain the metal porous body.

14. The method according to claim 8 , wherein the sintering is performed under a temperature of about 1200 to about 1400° C. for about 1 to 3 hours.

15. The method according to claim 8 , wherein the metal ring is welded to the ceramic ring by means of brazing, wherein the brazing is performed under a temperature of about 570 to about 660° C. for about 5 to 30 minutes under a vacuum or an inert atmosphere.

16. The method according to claim 15 , wherein in the step of brazing, an Al—Si alloy is used, wherein the weight of Si is about 12 wt % or less.

17. A lithium ion battery, comprising:

a shell having at least one open end;

a sealing assembly for sealing the open end to form a sealed space; and

a pole core and an electrolyte solution received in the sealed space, wherein

the sealing assembly comprises:

a ceramic ring having a receiving hole, wherein the ceramic ring is selected from a group consisting of alumina ceramic ring, zirconia ceramic ring, aluminum nitride ceramic ring, boron nitride ceramic ring, silicon nitride ceramic ring, and alumina-zirconia composite ceramic ring,

a metal ring fitted over the ceramic ring for sealing an open end of the battery,

a column formed in the receiving hole which comprises a metal-metal composite,

wherein the metal-metal composite comprises:

a metal porous body, wherein the metal porous body comprises a first metal and a second metal, and the first metal is Cu; the second metal is at least one selected from a group consisting of W and Mo,

a metal material filled in pores of the metal porous body, wherein the metal material is Cu; and

the metal ring of the sealing assembly is connected with the shell, and the core column of the sealing assembly is connected with the pole core,

wherein the expansion coefficient of the metal-metal composite is regulated to be approximate to the expansion coefficient of the ceramic ring.