Dual weld plug for an electrochemical cell

Patent metadata

Field	Value
Publication number	US-10109844-B2
Application number	US-201615341083-A
Country	US
Kind code	B2
Filing date	Nov 2, 2016
Priority date	Nov 2, 2016
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

The present invention is directed to an electrochemical cell having plate electrodes housed inside a mating “clamshell” casing. When mated together, the casing components are form-fitting with respect to the internal battery structure so as to reduce the overall size of the electrochemical package. A header assembly containing both a glass-to-metal seal opening for a terminal lead and an electrolyte fill opening is used in conjunction with the clamshell casing. The electrolyte fill opening is constructed with an elongated opening with at least two different radii. A first and second sealing element is welded within the electrolyte fill opening at different depths within the header to block the flow of electrolyte and form a hermetic seal.

First claim

What is claimed is:

1. An electrochemical cell, which comprises:
a) a casing comprising a casing sidewall having a header opening;
b) a header hermetically sealed to the casing sidewall in the header opening, the header having a thickness extending from a bottom header surface to a top header surface, wherein the header comprises an electrolyte fill opening, the electrolyte fill opening comprising:
i) a first opening portion comprising a first opening sidewall extending upwardly from the bottom header surface to a first ledge,
ii) wherein the first ledge extends laterally from an upper edge of the first opening sidewall to a second opening portion,
iii) the second opening portion comprising a second opening sidewall extending upwardly from the first ledge to a second ledge,
iv) wherein the second ledge extends laterally from an upper edge of the second opening sidewall to a third opening portion; and
v) the third opening portion comprising a third opening sidewall extending upwardly from the second ledge to the upper header surface,
vi) wherein the first, second and third opening portions have respective first, second and third diameters aligned substantially perpendicular to the header thickness with the first diameter being less than the second diameter, and with the second diameter being less than the third diameter;

c) an electrode assembly housed inside the casing, the electrode assembly comprising an anode prevented from direct physical contact with a cathode by an intermediate separator, wherein the anode and cathode are activated with an electrolyte filled into the casing through the electrolyte fill opening;
d) a first sealing member comprising a lower annular plug sidewall extending upwardly to an annular lip, the annular lip having a fourth diameter that is greater than the first diameter of the first opening portion, but less than the second diameter of the second opening portion, wherein, with the annular lip contacting the first ledge, the annular plug sidewall of the first sealing member is in a seal-contact relationship with the first opening sidewall, and wherein the lip of the first sealing member is welded to the header to thereby close the first opening portion; and
e) a second sealing member dimensioned to fit in the third opening portion, wherein the second sealing member is welded to the header to thereby close the third opening portion and create a hermetically sealed casing at the electrolyte fill opening.

2. The electrochemical cell of claim 1 wherein the first sealing member is characterized as having been welded to the first ledge of the header at a first welding energy and the second sealing member is characterized as having been welded to the header at a second welding energy, the second welding energy being greater than the first welding energy.

3. The electrochemical cell of claim 2 wherein the first welding energy ranges from about 1 Joule to about 2Joules and the second welding energy ranges from about 1.5Joules to about 3 Joules.

4. The electrochemical cell of claim 1 wherein the first and second sealing members are composed of a metallic material selected from the group consisting of titanium, nickel, copper, MP35N, and combinations thereof.

5. The electrochemical cell of claim 1 wherein the second sealing member comprises a sphere or a plate.

6. The electrochemical cell of claim 1 wherein the first, second and third opening portions are coaxial.

7. The electrochemical cell of claim 1 comprising a primary or secondary chemistry.

8. The electrochemical cell of claim 1 wherein the second sealing member has a fifth diameter that is in a contact relationship with the third diameter of the third opening sidewall.

9. An electrochemical cell, which comprises:
a) a casing comprising:
i) a first metal casing member having a first surrounding sidewall extending to and meeting with a first major face wall; and
ii) a second metal casing member having a second surrounding sidewall extending to and meeting with a second major face wall;

b) a header supported by at least one of the first and second casing members, the header having a thickness extending from a bottom header surface to a top header surface, wherein the header comprises an electrolyte fill opening, the electrolyte fill opening comprising:
i) a first opening portion comprising a first opening sidewall extending upwardly from the bottom header surface to a first ledge,
ii) wherein the first ledge extends laterally from an upper edge of the first opening sidewall to a second opening portion,
iii) the second opening portion comprising a second opening sidewall extending upwardly from the first ledge to a second ledge,
iv) wherein the second ledge extends laterally from an upper edge of the second opening sidewall to a third opening portion; and
v) the third opening portion comprising a third opening sidewall extending upwardly from the third ledge to the upper header surface,
vi) wherein the first, second and third opening portions have respective first, second and third diameters aligned substantially perpendicular to the header thickness with the first diameter being less than the second diameter, and with the second diameter being less than the third diameter;

c) wherein a first outer edge of the first surrounding sidewall faces the second major face wall with the first surrounding sidewall being in a hermetically sealed relationship with the second surrounding sidewall to thereby seal the first and second casing members together; and
d) an electrode assembly housed inside the casing, the electrode assembly comprising an anode prevented from direct physical contact with a cathode by an intermediate separator, wherein the anode and cathode are activated with an electrolyte filled into the casing through the electrolyte fill opening;
e) a first sealing member comprising a lower annular plug sidewall extending upwardly to an annular lip, the annular lip having a fourth diameter that is greater than the first diameter of the first opening portion, but less than the second diameter of the second opening portion, wherein, with the annular lip contacting the first ledge, the annular plug sidewall of the first sealing member is in a seal-contact relationship with the first opening sidewall, and wherein the lip of the first sealing member is welded to the header to thereby close the first opening portion; and
f) a second sealing member dimensioned to fit in the third opening portion, wherein the second sealing member is welded to the header to thereby close the third opening portion and create a hermetically sealed casing at the electrolyte fill opening.

10. The electrochemical cell of claim 9 wherein the first sealing member is characterized as having been welded to the first ledge of the header at a first welding energy and the second sealing member is characterized as having been welded to the header at a second welding energy, the second welding energy being greater than the first welding energy.

11. The electrochemical cell of claim 9 wherein the second sealing member comprises a sphere or a plate.

12. The electrochemical cell of claim 9 wherein the first sealing member has a cavity extending from the annular lip to a lower cavity portion surrounded by the lower annular plug sidewall where the cavity meets a plug bottom wall.

13. The electrochemical cell of claim 9 wherein the first, second and third opening portions are coaxial.

14. A method of providing an electrochemical cell, the method comprising the steps of:
a) providing an electrode assembly comprising an anode prevented from direct physical contact with a cathode

Assignees

• Greatbatch Ltd

Inventors

• Dai Xiangyang
• Freitag Gary
• Grubb Kenneth L
• Hallifax Paul T
• Roy Mark J
• Serpe Lou

Classifications

• H01M50/627

  Filling ports · CPC title

• H01M50/103

  prismatic or rectangular (H01M50/109, H01M50/11 take precedence) · CPC title

• H01M2/362

  Electricity · mapped topic

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M2220/30

  Batteries in portable systems, e.g. mobile phone, laptop · CPC title