Battery With Enhanced Resistance to Dendrite Formation

Patent metadata

Field	Value
Publication number	US-2019131592-A1
Application number	US-201816232169-A
Country	US
Kind code	A1
Filing date	Dec 26, 2018
Priority date	Nov 16, 2016
Publication date	May 2, 2019
Grant date	—

Abstract

A battery includes a case having a feedthrough port, a feedthrough assembly disposed in the feedthrough port, and a cell stack disposed within the case. The feedthrough port includes an inner conductor and an insulator core separating the inner conductor from the case. The cell stack includes an anode, a cathode, and a separator insulating the anode from the cathode, wherein the anode and cathode are offset from one another. An insulating boot surrounding the cell stack insulates the cell stack from the case. The insulating boot has an opening configured to receive therein the feedthrough assembly, which may include overmolded insulation. The interior surfaces and interior walls of the battery case may be thermal spray-coated with a dielectric material to prevent lithium dendrite formation between cathode and anode surfaces.

First claim

1 . (canceled)

2 . A battery, comprising:
a case having a feedthrough port; a feedthrough assembly disposed in the case and extending into the feedthrough port, the feedthrough assembly including
a ferrule having a lumen;
an inner conductor disposed within the lumen of the ferrule;
an insulating core disposed within the lumen of the ferrule and separating the inner conductor from the ferrule; and
feedthrough insulation disposed circumferentially around a portion of the ferrule;
a cell stack disposed within the case, the cell stack including
an anode having a main anode body and an anode tab projecting from the main anode body;
a cathode having a main cathode body and a cathode tab projecting from the main cathode body; and
one or more separator layers disposed between the main anode body and the main cathode body and electrically insulating the anode from the cathode; and
an insulating boot formed from a material having a thickness, the insulating boot surrounding the cell stack to electrically insulate the cell stack from the case, the insulating boot having a body and an annular lip projecting outwardly from the body, the lip circumscribing an aperture in the insulating boot, the feedthrough assembly being disposed in the lip so that the lip circumferentially surrounds at least a portion of the feedthrough insulation, the portion of the feedthrough insulation being at least three times the thickness of the material forming the insulating boot.

3 . The battery as claimed in claim 2 , wherein the material of the insulating boot is selected from the group consisting of polyethylene (PE), polycarbonate (PC), ethylenetetrafluorethylene (ETFE), polyetheretherketone (PEEK), polypropylene (PP), and mixtures thereof.

4 . The battery as claimed in claim 3 , wherein the material of the insulating boot has an average pore diameter of up to 0.05 μm.

5 . The battery as claimed in claim 3 , wherein the feedthrough insulation comprises a material selected from the group consisting of polyethylene (PE), ethylenetetrafluorethylene (ETFE), polyetheretherketone (PEEK), polypropylene (PP), polyurethane (PU), polycarbonate (PC), silicones, and mixtures thereof.

6 . The battery as claimed in claim 2 , wherein the separator layers and the insulating boot are formed from the same material.

7 . The battery as claimed in claim 2 , wherein the insulating boot forms a liquid-tight seal with the feedthrough insulation, the liquid-tight seal being formed by heat sealing, a compression joint, an adhesive or a combination thereof.

8 . The battery as claimed in claim 7 , wherein the insulating boot is heat-sealed to the feedthrough insulation by laser welding, radio-frequency welding, resistive welding, friction welding, or a combination thereof.

9 . The battery as claimed in claim 2 , wherein the insulating boot includes a first portion and a second portion that are initially separate from one another, the second portion being sealed to the first portion.

10 . The battery as claimed in claim 2 , wherein the insulating core is formed of glass.

11 . The battery as claimed in claim 2 , wherein the feedthrough insulation is an electrically insulating material.

12 . The battery as claimed in claim 2 , wherein the annular lip of the insulating boot is bonded to the feedthrough insulation.

13 . The battery as claimed in claim 2 , wherein the portion of the feedthrough insulation is between 10 times and 15 times the thickness of the material forming the insulating boot.

14 . A method of manufacturing an electrochemical cell, the method comprising:
providing a case having a feedthrough port; preparing a cell stack including an anode, a cathode and one or more separator layers electrically insulating the anode from the cathode; assembling a feedthrough assembly in an insulating boot, the insulating boot being formed from a material having a thickness, the insulating boot having a body and an annular lip projecting outwardly from the body, the lip circumscribing an aperture in the insulating boot, the feedthrough assembly including
a ferrule having a lumen;
an inner conductor disposed within the lumen of the ferrule;
an insulating core disposed within the lumen of the ferrule and separating the inner conductor from the ferrule; and
feedthrough insulation disposed circumferentially around a portion of the ferrule;
assembling the feedthrough assembly in the lip of the insulating boot so that the lip circumferentially surrounds at least a portion of the feedthrough insulation, the portion of the feedthrough insulation being at least three times the thickness of the material forming the insulating boot; inserting the cell stack into the insulating boot to form a covered cell assembly; and inserting the covered cell assembly into the case to form a completed electrochemical cell.

15 . The method as claimed in claim 14 , wherein the insulating boot is formed from a material selected from the group consisting of polyethylene (PE), polycarbonate (PC), ethylenetetrafluorethylene (ETFE), polyetheretherketone (PEEK), polypropylene (PP), and mixtures thereof.

16 . The method as claimed in claim 15 , wherein the insulating boot is formed from a material having an average pore diameter of up to 0.05 μm.

17 . The method as claimed in claim 14 , wherein the separator layers and the insulating boot are formed from the same material.

18 . The method as claimed in claim 14 , wherein the step of assembling the feedthrough assembly in the lip of the insulating boot includes forming a liquid-tight seal between the insulating boot and the feedthrough insulation by heat sealing, a compression joint, an adhesive or a combination thereof.

19 . The method as claimed in claim 18 , wherein the insulating boot is heat-sealed to the feedthrough insulation by laser welding, radio-frequency welding, resistive welding, friction welding or a combination thereof.

20 . The method as claimed in claim 14 , wherein the feedthrough insulation is disposed around the portion of the ferrule by an overmolding process.

21 . The method as claimed in claim 14 , wherein the step of assembling the feedthrough assembly in the insulating boot includes assembling the feedthrough assembly in a first portion of the insulating boot and assembling a second portion of the insulating boot to the first portion of the insulating boot to enclose the cell stack.

Assignees

• Pacesetter Inc

Inventors

• Bruch Russell
• Armstrong Jeffrey
• Beauvais Joseph

Classifications

• H01M4/131 Primary

  Electrodes based on mixed oxides or hydroxides, or on mixtures of oxides or hydroxides, e.g. LiCoOx · CPC title

• H01M4/133

  Electrodes based on carbonaceous material, e.g. graphite-intercalation compounds or CFx · CPC title

• C01G5/00

  Compounds of silver · CPC title

• C01G31/02

  Oxides · CPC title

• H01M50/176

  for prismatic or rectangular cells (H01M50/181 takes precedence) · CPC title