Rechargeable hearing aid battery with slotted grommet

Patent metadata

Field	Value
Publication number	US-2020083497-A1
Application number	US-201916567478-A
Country	US
Kind code	A1
Filing date	Sep 11, 2019
Priority date	Sep 11, 2018
Publication date	Mar 12, 2020
Grant date	—

Abstract

A rechargeable hearing aid battery includes a stack of active materials forming a core, a two-part casing including an inner casing and an outer casing, and a grommet. The grommet includes an opening through which a conductive tab extends. The conductive tab is configured to electrically connect an electrode of the core to one of the outer casing and the inner casing. The grommet is configured to insulate a portion of the tab from the core and to insulate the core from one of the outer casing and the inner casing. Furthermore, the grommet is configured to separate the inner casing from the outer casing and to seal a gap formed between the inner and outer casing.

First claim

What is claimed is:

1 . A button cell battery comprising:
a casing comprising:
an inner casing;
an outer casing that at least partially surrounds the inner casing, wherein together the outer casing and the inner casing define an internal volume;
a core disposed in the internal volume, the core comprising:
a first electrode;
a second electrode;
at least one separator layer disposed between the first electrode and the second electrode; and
a first tab having a first end and a second end, wherein the first end is attached to one of the first electrode and the second electrode and the second end is attached to one of the outer casing and the inner casing; and
a grommet disposed at least partially between the inner casing and the outer casing, the grommet comprising an opening, wherein the core is separated from one of the outer casing and the inner casing by the grommet, and wherein the tab extends through the opening.

2 . The button cell battery of claim 1 , wherein the opening is a rectangular slot.

3 . The button cell battery of claim 1 , wherein the first tab is welded to one of the outer casing and the inner casing.

4 . The button cell battery of claim 1 , wherein the opening is disposed in a bottom wall of the grommet, wherein the bottom wall of the grommet is solid other than the opening.

5 . The button cell battery of claim 1 , the grommet further including a sidewall attached to and extending upwards relative to an outer periphery of the bottom wall of the grommet;
wherein the grommet bottom wall is disposed between a lower surface of the outer casing and an upper surface of the inner casing, and the grommet sidewall is disposed between an outer surface of a sidewall of the inner casing and an inner surface of a sidewall of the outer casing.

6 . The button cell battery of claim 1 , wherein the grommet is configured to seal a gap between the inner casing and the outer casing.

7 . The button cell battery of claim 1 , the core further comprising a mandrel, wherein the first electrode, the second electrode, a first separator layer, and a second separator layer are arranged in a stack, wherein the first separator layer and the second separator layer are disposed on opposite sides of the first electrode or second electrode, wherein the stack is wound in a spiral configuration around the mandrel.

8 . The button cell battery of claim 7 , wherein a height of the mandrel parallel to an axis of the mandrel is greater than a height of the stack parallel to the axis of the mandrel.

9 . The button cell battery of claim 7 , wherein a height of each of the first separator layer and the second separator layer parallel to an axis of the mandrel is greater than a height of both the first electrode and the second electrode parallel to the axis of the mandrel.

10 . The button cell battery of claim 7 , wherein the first electrode is welded to the mandrel before winding the stack about the mandrel.

11 . The button cell battery of claim 10 , wherein the first electrode is an anode of the button cell battery and the second electrode is a cathode of the button cell battery.

12 . The button cell battery of claim 10 , wherein the first electrode is an cathode of the button cell battery and the second electrode is a anode of the button cell battery.

13 . A method of assembly for a button cell battery, the button cell battery comprising an active core, an inner casing defining an upper cavity, an outer casing defining a lower cavity, and a grommet that is configured to separate the active core from the outer casing, the method comprising:
inserting the active core into one of the upper cavity and the lower cavity, the active core comprising a stack, the stack comprising a first electrode and a second electrode; inserting a tab through an opening in the grommet, wherein a first end of the tab is attached to one of the first electrode and the second electrode; and fitting the inner casing to the outer casing, wherein the grommet separates the inner casing from the outer casing.

14 . The method of claim 13 , wherein the opening is a rectangular slot.

15 . The method of claim 13 , further comprising folding an upper edge of the outer casing over the grommet and the inner casing.

16 . The method of claim 13 , the stack further comprising a first separator layer, and a second separator layer, wherein the first separator layer and the second separator layer are disposed on opposite sides of the first electrode, the method further comprising:
welding the first electrode to a mandrel; and winding the stack in a spiral configuration around the mandrel to form the active core.

17 . The method of claim 16 , further comprising welding the mandrel to the inner casing.

18 . The method of claim 16 , further comprising welding the mandrel to the outer casing.

19 . A button cell battery comprising:
a casing comprising:
an inner casing; and
an outer casing that at least partially surrounds the inner casing, wherein together the inner casing and the outer casing define an internal volume;
a core disposed in the internal volume;

a first tab configured to electrically couple a portion of the core to one of the inner casing and the outer casing; and a grommet disposed within the internal volume between the core and at least one of the outer casing and the inner casing, wherein:
the grommet is configured to electrically insulate the outer casing from the inner casing,
the grommet is configured to electrically insulate the core from one of the outer casing and the inner casing, and
the grommet is configured to electrically insulate a portion of the first tab from the core.

20 . The button cell battery of claim 19 , wherein the first tab extends through a rectangular slot in the grommet.

Assignees

• Energizer Brands Llc

Inventors

• Sabrowsky Benjamin
• Syvertsen Marc
• Imhoff Casey
• Proffit Danielle
• Karsseboom Jacob

Classifications

• H01M10/0427 Primary

  Button cells · CPC title

• H01M10/0431

  Cells with wound or folded electrodes (H01M10/045 takes precedence) · CPC title

• H01M2220/30

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

• H01M2/0222

  Electricity · mapped topic

• H01M2/06 Primary

  Electricity · mapped topic