Protective element, protective element fabrication method, and battery module in which protective element is embedded

Patent metadata

Field	Value
Publication number	US-9337671-B2
Application number	US-201214366630-A
Country	US
Kind code	B2
Filing date	Dec 17, 2012
Priority date	Dec 19, 2011
Publication date	May 10, 2016
Grant date	May 10, 2016

Abstract

A protective element including a substrate having a first insulating member and a concave portion formed thereon, a heating body layered on the concave portion of the substrate, a second insulating member layered on the substrate so as to cover at least covering the heating body, first and second electrodes layered on a surface of the substrate on which the second insulating member is layered, a heating body electrode layered on the second insulating member so as to be superimposed with the heating body, and electrically connected to a current path between the first and the second electrodes as well as onto and the heating body, and a low-melting point metal layered from the heating body electrode toward the first and the second electrodes configured to cause a blowout of the current path between the first and the second electrodes by heating.

First claim

The invention claimed is:

1. A protective element comprising:
a substrate comprising a first insulating member and a concave portion;
a heating body layered on the concave portion of the substrate;
a second insulating member layered on the substrate covering the heating body;
first and second electrodes layered on a surface of the substrate on which the second insulating member is layered;
a heating body electrode layered on the second insulating member superimposed with the heating body, and electrically connected to a current path between the first and the second electrodes and the heating body; and
a low-melting point metal layered between the heating body electrode and the first and the second electrodes so as to cause a blowout of the current path between the first and the second electrodes by heating,
wherein the heating body electrode is disposed at a same or lower position in a thickness direction of the substrate relative to the first and the second electrodes.

2. The protective element according to claim 1 , wherein the heating body and the second insulating member are embedded into the concave portion formed on the substrate.

3. The protective element according to claim 1 , wherein the heating body is disposed at a lower position relative to the first and the second electrodes in the thickness direction of the substrate.

4. The protective element according to claim 3 , wherein the second insulating member comprises a member having a thermal conductivity higher than that of the first insulating member.

5. A method for manufacturing a protective element comprising:
stacking a heating body in a concave portion formed on a substrate comprising a first insulating member;
stacking a second insulating member on the substrate covering the heating body;
stacking first and second electrodes on a surface of the substrate on which the second insulating member is stacked;
stacking a heating body electrode on the second insulating member so as to be superimposed with the heating body, the heating body electrode electrically connected to a current path between the first and the second electrodes and the heating body; and
stacking, from the heating body electrode to the first and the second electrodes, a low-melting point metal so as to cause a blowout of the current path between the first and the second electrodes by heating,
wherein the heating body electrode is disposed at a same or lower position in a thickness direction of the substrate relative to the first and the second electrodes.

6. A battery module comprising:
a battery comprising one or more battery cells;
a charging and discharging control circuit connected to the battery in series to control charging and discharging of the battery;
a protective element connected to a charging and discharging current path between the battery and the charging and discharging control circuit;
a detection circuit for detecting a voltage value of each of the one or more battery cells of the battery; and
a current control element for controlling an electric current flowing through the protective element, the protective element further comprising:
a substrate comprising a first insulating member and a concave portion;
a heating body layered on the concave portion of the substrate;
a second insulating member layered on the substrate covering the heating body;
first and second electrodes layered on a surface of the substrate on which the second insulating member is layered and connected to the charging and discharging current path,
a heating body electrode layered on the second insulating member superimposed with the heating body and electrically connected to a current path between the first and the second electrodes and the heating body; and
a low-melting point metal layered between the heating body electrode and the first and the second electrodes so as to cause a blowout of a current path between the first and the second electrodes by heating,
wherein the heating body electrode is disposed at a same or lower position in a thickness direction of the substrate relative to the first and second electrodes, and
wherein the current control element carries out a controlling process such that when a voltage value of each of the one or more battery cells detected by the detection circuit is of not within a predetermined range, a current is allowed to flow from the heating body electrode to the heating body.

7. A protective element comprising:
a substrate comprising an insulating member;
first and second electrodes layered on a surface of the substrate;
a substrate electrode layered between the first and the second electrodes on the surface of the substrate;
a low-melting point metal layered between the substrate electrode and the first and the second electrodes so as to cause a blowout of a current path between the first and the second electrodes by heating,
a cap covering the surface of the substrate;
a heating body formed on a ceiling surface portion of the cap; and
a heating body electrode layered on the surface of the substrate and electrically connected to the heating body through a conductive layer formed on the cap,
wherein the substrate electrode is disposed at a same or lower position in a thickness direction of the substrate relative to the first and the second electrodes.

8. A battery module comprising:
a battery comprising one or more battery cells;
a charging and discharging control circuit connected to the battery in series to control charging and discharging of the battery;
a protective element connected to a charging and discharging current path between the battery and the charging and discharging control circuit;
a detection circuit for detecting a voltage value of each of the one or more battery cells;
a current control element for controlling an electric current flowing through the protective element, the protective element comprising:
a substrate comprising an insulating member;
first and second electrodes layered on a surface of the substrate;
a substrate electrode layered between the first and the second electrodes on the surface of the substrate;
a low-melting point metal layered between the substrate electrode and the first and the second electrodes so as to cause a blowout of a current path between the first and the second electrodes by heating,
a cap covering the surface of the substrate;
a heating body formed on a ceiling surface portion of the cap; and
a heating body electrode layered on the surface of the substrate and electrically connected to the heating body through a conductive layer formed on the cap,
wherein the substrate electrode is disposed at a same or lower position in a thickness direction of the substrate relative to the first and the second electrodes, and
wherein the current control element carries out a controlling process such that when a voltage value of each of the one or more battery cells detected by the detection circuit is not within a predetermined range, a current is allowed to flow from the heating body electrode to the heating body.

Assignees

• Dexerials Corp

Inventors

• Komori Chisato
• Furuuchi Yuji
• Yoneda Yoshihiro
• Mukai Koichi
• Ejima Koji
• Fujihata Takashi
• Furuta Kazutaka
• Araki Toshiaki

Classifications

• H02J7/63

  against overdischarge · CPC title

• H02J7/61

  against overcharge · CPC title

• H02J7/663

  using battery or load disconnect circuits (H02J9/002 takes precedence) · CPC title

• Y10T29/49208

  by assembling plural parts · CPC title

• H01M10/0525

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