Sealed battery and manufacturing method of sealed battery
A sealed battery ( 1 ) is provided with a current interrupting mechanism ( 62 ) that interrupts current that flows through an electrode body ( 10 ) when an internal pressure (F) of a battery case ( 80 ) exceeds an operating pressure (G). The current interrupting mechanism includes a movable member ( 64 ) that includes a moving portion ( 64 A) that moves with a rise in the internal pressure, and a conductive member ( 63 ) that is electrically connected to the electrode body. The conductive member ( 63 ) includes a protruding portion ( 63 A) that protrudes toward the moving portion. A weld (PT) created by welding using an energy beam is interposed between the protruding portion and the moving portion. The conductive member has, around the protruding portion, an annular groove ( 63 BG) that fractures in an annular shape surrounding the weld when the internal pressure exceeds the operating pressure. The protruding portion elastically pushes against the moving portion via the weld.
1. A sealed battery comprising:
an electrode body including an electrode plate;
a battery case that encloses the electrode body; and
a current interrupting mechanism including a movable member and a conductive member, the movable member including a moving portion being configured to move with a rise in an internal pressure in the battery case, the conductive member being electrically connected to the electrode plate of the electrode body, and the current interrupting mechanism being configured to interrupt current that flows through the electrode body when the internal pressure in the battery case exceeds an operating pressure, wherein
the conductive member includes a circular through-hole, and a protruding portion disposed at a peripheral edge of the circular through-hole so as to have a circular shape and surround the circular through-hole, wherein the protruding portion protrudes toward the moving portion;
a weld made by energy beam welding is interposed between the protruding portion and the moving portion;
the conductive member has an annular groove having a circular shape and that is concentric around the protruding portion that is disposed at the peripheral edge of the circular through-hole, the annular groove is configured to fracture in an annular shape surrounding the weld when the internal pressure exceeds the operating pressure; and
the protruding portion is configured to elastically push against the moving portion via the weld.
2. A manufacturing method for a sealed battery, the sealed battery including:
an electrode body including an electrode plate;
a battery case that encloses the electrode body; and
a current interrupting mechanism including a movable member and a conductive member, the movable member including a moving portion being configured to move with a rise in an internal pressure in the battery case, the conducting member being electrically connected to the electrode plate of the electrode body, and the current interrupting mechanism being configured to interrupt current that flows through the electrode body when the internal pressure in the battery case exceeds an operating pressure, the conductive member including a circular through-hole, and a protruding portion disposed at a peripheral edge of the circular through-hole so as to have a circular shape and surround the circular through-hole, wherein the protruding portion protrudes toward the moving portion;
a weld made by energy beam welding being interposed between the protruding portion and the moving portion, and
the conductive member having an annular groove having a circular shape and that is concentric around the protruding portion that disposed at the peripheral edge of the circular through-hole, the annular groove being configured to fracture in an annular shape surrounding the weld when the internal pressure exceeds the operating pressure,
the manufacturing method comprising:
elastically abutting the protruding portion against the moving portion; and
welding the moving portion to the protruding portion by emitting the energy beam at the protruding portion.
3. The sealed battery according to claim 1 , wherein the protruding portion is configured to elastically push against the moving portion before the weld is interposed therebetween.
4. The manufacturing method according to claim 2 , wherein the protruding portion is elastically abutted against the moving portion before the welding.