Electricity storage device

Patent metadata

Field	Value
Publication number	US-10115956-B2
Application number	US-201515128741-A
Country	US
Kind code	B2
Filing date	Mar 11, 2015
Priority date	Mar 27, 2014
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

An electricity storage device includes an electrode assembly, a case, a first terminal, and a second terminal. The electrode assembly includes one or more first electrodes and one or more second electrodes, which are stacked alternately with one or more separators in between. The case accommodates the electrode assembly. The first terminal and the second terminal are located on a wall portion of the case. First tabs and second tabs are provided on ends of the first and second electrodes, respectively. A circuit breaker is arranged between the second terminal and the electrode assembly. A part of the first terminal and the first tabs are arranged along the width direction of the electrode assembly, and the circuit breaker and the second tabs are arranged along the width direction of the electrode assembly.

First claim

The invention claimed is:

1. An electricity storage device comprising:
an electrode assembly, in which one or more first electrodes and one or more second electrodes, which are electrodes, are stacked alternately with one or more separators in between;
a case, which accommodates the electrode assembly;
a first terminal and a second terminal, which are exposed to an outside from a wall portion of the case, a part of each terminal protruding toward the electrode assembly, wherein
each first electrode has a first tab, which has a shape protruding from an end of the first electrode,
each second electrode has a second tab, which has a shape protruding from an end of the second electrode, and
the electrode assembly has an end face on which the first and second tabs are located, the end face facing the wall portion,

a circuit breaker, which is arranged between the second terminal and the electrode assembly and is joined to the second terminal;
a first conductor, which is joined to the first tabs and the first terminal; and
a second conductor, which is joined to the circuit breaker and the second tabs, wherein
the first conductor has a first bend portion, which is bent into a shape of a crank when viewed along a stacking direction of the electrodes,
the second conductor has a second bend portion, which is bent into a shape of a crank when viewed along a stacking direction of the electrodes,
a direction that is perpendicular to both the stacking direction of the electrodes and a direction along which the wall portion and the end face face each other is defined as a width direction of the electrode assembly,
a part of the first terminal and the first tabs are arranged along the width direction of the electrode assembly,
the circuit breaker and the second tabs are arranged along the width direction of the electrode assembly,
the first conductor includes
a terminal joint portion, which is joined to the first terminal, and
a first tab joint portion, which is arranged closer to the wall portion than the terminal joint portion and includes a first tab joint face joined to the first tabs and a first opposed face facing the wall portion,

the second conductor includes
a breaker joint portion, which is joined to the circuit breaker, and
a second tab joint portion, which is arranged closer to the wall portion than the breaker joint portion and includes a second tab joint face joined to the second tabs and a second opposed face facing the wall portion,

the breaker joint portion and the terminal joint portion are displaced from each other along the facing direction,
the first bend portion and the second bend portion are bent such that the first opposed face and the second opposed face approach each other along the facing direction, and
the second bend portion of the second conductor is narrower than the first bend portion of the first conductor in the stacking direction of the electrodes.

2. The electricity storage device according to claim 1 , further comprising an insulating cover, which is arranged between the wall portion and a set of the first tab joint portion and the second tab joint portion,
wherein the insulating cover contacts both the first opposed face and the second opposed face.

3. The electricity storage device according to claim 1 , wherein
the first tab joint portion and the second tab joint portion are each plate-shaped, and
at least one of the first tab joint portion and the second tab joint portion includes a thick portion and a thin portion, which have different thicknesses.

4. The electricity storage device according to claim 1 , wherein at least one of the first bend portion and the second bend portion has a constricted section.

5. The electricity storage device according to claim 1 , wherein the electricity storage device is a rechargeable battery.

6. The electricity storage device according to claim 1 , further comprising a first insulating member having an insulating property, which is integrated with the terminal joint portion and located between the terminal joint portion and the end face of the electrode assembly, wherein,
in a face of the first bend portion that faces the electrode assembly, a part that is closest to the electrode assembly is defined as a first facing portion, and a distance from the first facing portion to the first tab joint face is defined as a bend portion distance,
in a state in which the first tabs are gathered on a side closer to the electrode assembly and the first conductor, which is joined to the first tabs, has been displaced toward the electrode assembly,
a distance along the facing direction between the first insulating member and the end face of the electrode assembly is defined as a separation distance, and
a value obtained by adding up the thicknesses of a total number of the first tabs and doubling the added-up value is defined as a tab stacking distance,

the electricity storage device comprises a second insulating member having an insulating property, which is integrated with the circuit breaker and located between the circuit breaker and the end face of the electrode assembly,
in a face of the second bend portion that faces the electrode assembly, a part that is closest to the electrode assembly is defined as a second facing portion, and a distance from the second facing portion to the second tab joint face is defined as a bend portion distance,
in a state in which the second tabs are gathered on a side closer to the electrode assembly and the second conductor, which is joined to the second tabs, has been displaced toward the electrode assembly,
a distance along the facing direction between the second insulating member and the end face of the electrode assembly is defined as a separation distance, and

when a value obtained by adding up the thicknesses of a total number of the second tabs and doubling the added-up value is defined as a tab stacking distance, the following expression is satisfied: (Bend portion distance)<(Tab stacking distance)−(Separation distance).

7. An electricity storage device comprising:
an electrode assembly, in which one or more first electrodes and one or more second electrodes, which are electrodes, are stacked alternately with one or more separators in between;
a case, which accommodates the electrode assembly;
a first terminal and a second terminal, which are exposed to an outside from a wall portion of the case, a part of each terminal protruding toward the electrode assembly, wherein
each first electrode has a first tab, which has a shape protruding from an end of the first electrode,
each second electrode has a second tab, which has a shape protruding from an end of the second electrode, and
the electrode assembly has an end face on which the first and second tabs are located, the end face facing the wall portion,

a circuit breaker, which is arranged between the second terminal and the electrode assembly and is joined to the second terminal;
a first conductor, which is joined to the first tabs and the first terminal; and
a second conductor, which is joined to the circuit breaker and the second tabs, wherein
the first conductor has a first bend portion, which is bent into a shape of a crank when viewed along a stacking direction of the electrodes,
the second conductor has a second bend portion, which is bent into a shape of a crank when viewed along a stacking direction of the electrodes,
a direction that is perpendicular to both the stacking direction of the electrodes and a direction along which the wall portion and the end face face each other is defined as a width direction of the electrode assembly,
a part of the first terminal and the first tabs are arranged along the width direction of the electrode assembly,
the circuit breake

Assignees

• Toyota Jidoshokki Kk

Inventors

• Mune Shimpei
• Yamashita Yusuke
• Okuda Motoaki
• Tachibana Tomoaki

Classifications

• H01G11/74 Primary

  Terminals, e.g. extensions of current collectors · CPC title

• H01M50/583

  in response to current, e.g. fuses · CPC title

• H01M50/176

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

• H01M50/533

  characterised by the shape of the leads or tabs · CPC title

• H01G11/26

  characterised by their structure, e.g. multi-layered, porosity or surface features · CPC title