Non-aqueous electrolyte secondary battery
A non-aqueous electrolyte secondary battery includes: an electrode assembly; a rectangular outer casing; a sealing plate; an electrode terminal on the sealing plate; a first current collector connected to the electrode terminal; a second current collector connected to the first current collector; and a tab group connected to the second current collector. The second current collector is a flat plate, and includes a fuse portion having a slit extending in a lateral direction of the flat plate. The tab group is connected to the second current collector at a position closer to one side in the lateral direction, and is bent at a connection portion with the second current collector such that the bent tab group extends parallel to the side wall. The fuse portion includes a portion with a large sectional area on the other side of the slit in the lateral direction.
1 . A non-aqueous electrolyte secondary battery, comprising a plurality of electrode assemblies,
wherein each of the plurality of electrode assemblies comprises:
a positive electrode plate and a negative electrode plate;
a rectangular outer casing having an opening and housing the electrode assembly;
a sealing plate sealing the opening;
an electrode terminal located on the sealing plate;
a first current collector located between the electrode assembly and the sealing plate and connected to the electrode terminal;
a second current collector located between the electrode assembly and a side wall of the rectangular outer casing and connected to the first current collector; and
a tab group extending from the electrode assembly toward the side wall and connected to the second current collector,
wherein the second current collector is a flat plate including a surface parallel to the side wall, and includes a fuse portion having a slit extending in a lateral direction of the flat plate,
the tab group is connected to the second current collector at a position closer to one side of the slit than the other side of the slit opposite to the one side in the lateral direction of the flat plate, and is bent at a connection portion with the second current collector such that the bent tab group extends parallel to the side wall,
the fuse portion includes a portion on the other side of the slit in the lateral direction of the flat plate, and a sectional area of the portion on the other side of the slit in the lateral direction of the flat plate is larger than a sectional area of a portion on the one side of the slit in the lateral direction of the flat plate,
each of the plurality of second current collectors is connected to the corresponding tab group of the plurality of electrode assemblies, and
each of the plurality of second current collectors is connected to the first current collector such that each of the plurality of electrode assemblies has an electrically isolated current path, whereby, even if an abnormality occurs in one electrode assembly and the fuse portion of the corresponding second current collector is blown, the current paths of the other electrode assemblies remain electrically and structurally intact.
2 . The non-aqueous electrolyte secondary battery of claim 1 , wherein
the portion on the other side of the slit in the lateral direction of the flat plate is wider than the portion on the one side of the slit in the lateral direction of the flat plate.
3 . The non-aqueous electrolyte secondary battery of claim 2 , wherein
the slit is offset toward the one side in the lateral direction of the flat plate.
4 . The non-aqueous electrolyte secondary battery of claim 2 , wherein
the fuse portion has a cut on the one side of the slit in the lateral direction of the flat plate.
5 . The non-aqueous electrolyte secondary battery of claim 2 , wherein
the fuse portion includes an extended portion on the other side of the slit in the lateral direction of the flat plate, the extended portion being extended in the lateral direction.
6 . The non-aqueous electrolyte secondary battery of claim 1 , wherein
the fuse portion includes a protrusion on the other side of the slit in the lateral direction of the flat plate, the protrusion protruding in a thickness direction.
7 . The non-aqueous electrolyte secondary battery of claim 1 , wherein
the portion on the other side of the slit in the lateral direction of the flat plate is thicker than the portion on the one side of the slit in the lateral direction of the flat plate.
8 . A non-aqueous electrolyte secondary battery, comprising a plurality of electrode assemblies,
wherein each of the plurality of electrode assemblies comprises:
an electrode assembly including a positive electrode plate and a negative electrode plate;
a rectangular outer casing having an opening and housing the electrode assembly;
a sealing plate sealing the opening;
an electrode terminal located on the sealing plate;
a first current collector located between the electrode assembly and the sealing plate and connected to the electrode terminal;
a second current collector located between the electrode assembly and a side wall of the rectangular outer casing and connected to the first current collector; and
a tab group extending from the electrode assembly toward the side wall and connected to the second current collector,
wherein the second current collector is a flat plate including a surface parallel to the side wall, and includes a fuse portion having a thin portion that is thinner than the remaining portion in a lateral direction of the flat plate,
the tab group is connected to the second current collector at a position closer to one side of the thin portion than the other side of the thin portion opposite to the one side in the lateral direction of the flat plate, and is bent at a connection portion with the second current collector such that the bent tab group extends parallel to the side wall,
the fuse portion includes a portion on the other side of the thin portion in the lateral direction of the flat plate, and a sectional area of the portion on the other side of the thin portion in the lateral direction of the flat plate is larger than a sectional area of a portion on the one side of the thin portion in the lateral direction of the flat plate,
each of the plurality of second current collectors is connected to the corresponding tab group of the plurality of electrode assemblies, and
each of the plurality of second current collectors is connected to the first current collector such that each of the plurality of electrode assemblies has an electrically isolated current path, whereby, even if an abnormality occurs in one electrode assembly and the fuse portion of the corresponding second current collector is blown, the current paths of the other electrode assemblies remain electrically and structurally intact.
9 . The non-aqueous electrolyte secondary battery of claim 1 , wherein each of the plurality of second current collectors includes a current collector connection portion, a tilted portion, and a tab connection portion, the current collector connection portion is connected to the first current collector, the corresponding tab group is connected to the tab connection portion, the tilted portion connects the current collector connection portion and the tab connection portion, and is tilted with respect to both of the current collector connection portion and the tab connection portion.