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EP-3813151-B1 - BATTERY MODULE

EP3813151B1EP 3813151 B1EP3813151 B1EP 3813151B1EP-3813151-B1

Inventors

  • Ojima, Kazunori
  • AOKI, SADAYUKI
  • KUBOTA, OSAMU
  • WATAHIKI, YOSHITAKA

Dates

Publication Date
20260506
Application Date
20190301

Claims (4)

  1. A battery pack (BP) comprising battery modules connected in series to a pack fuse of a battery pack (BP), the battery module (BM) comprising: a plurality of battery cells, a cell blocking portion (CB) in a current path inside each of the plurality of battery cells, the cell blocking portion (CB) being configured to interrupt the current path in response to a current of a predetermined current value or higher flowing through the current path; a pair of module terminals connected to the plurality of battery cells; and a module fuse (MF) connected in series to the pair of module terminals and the plurality of battery cells, wherein each battery cell (BC) includes a cell container (C10), a storage element (C20) stored in the cell container (C10), a pair of cell terminals positioned outside the cell container (C10), and a connection terminal (C30) that electrically connects the pair of cell terminals to the storage element (C20), the module fuse (MF) is in a bus bar connected to the cell terminals of each of the plurality of battery cells, and characterized in that a current value at which the module fuse (MF) blows out is larger than a current value at which the pack fuse blow out, a current value at which the cell blocking portion (CB) interrupts the current path is larger than the current value at which the module fuse (MF) blows out, and the current value at which the module fuse (MF) blows out is larger than an average value of the current value at which the cell blocking portion (CB) interrupts the current path and the current value at which the pack fuse blows out.
  2. The battery pack (BP) according to claim 1, wherein the cell blocking portion (CB) is placed between one of the pair of cell terminals and the connection terminal (C30), and includes a current interruption valve (C40) configured to interrupt the current path between the cell terminal (CT) and the connection terminal (C30) in response to an increase in internal pressure of the cell container (C10).
  3. The battery pack (BP) according to claim 1, further comprising: a plurality of intermediate bus bars and a pair of end bus bars, wherein the plurality of intermediate bus bars each connect to a positive cell terminal of one of corresponding mutually adjacent battery cells of the plurality of battery cells in a stacking direction of the battery cells and to a negative cell terminal of the other battery cell (BC) so as to connect all of the battery cells in the battery module (BM) in series, the pair of end bus bars connects to two of the plurality of battery cells at both ends in the stacking direction of the plurality of battery cells connected via the intermediate bus bars, and to a positive-electrode cell terminal of one of the two battery cells and to a negative-electrode cell terminal of the other battery cell (BC), and the module fuse (MF) is positioned in the end bus bars.
  4. The battery pack (BP) according to claim 3, wherein the pair of end bus bars each has a slot at a bent corner, and the module fuse (MF) includes parts on both sides of the slot.

Description

Technical Field The present invention relates to a battery pack including a battery module including a plurality of battery cells. Background Art Conventionally inventions about a battery pack have been known, the battery pack having an assembled battery fuse connected to battery cells and a battery pack fuse connected to a battery unit, and the battery pack fuse has a constant set so that the battery pack fuse blows out faster than the assembled battery fuse (see Patent Literature 1). The invention described in Patent Literature 1 relates to a battery pack to be mounted on a vehicle, including the battery unit and the battery pack fuse, and has the following configuration (see the document, claim 1, for example). The battery unit includes a plurality of assembled batteries each having battery cells and an assembled battery fuse connected in series to the battery cells. The battery pack fuse is connected in series to the battery unit, and has a constant set so as to blow out faster than the assembled battery fuse when a current exceeding the rating flows through the battery unit. The battery pack fuse is placed above the battery unit in the vertical direction. With this configuration, the battery pack fuse is placed outside the case, and so a user does not have to remove a part of the case or do the work in the limited space inside the case, and so replaces the battery pack fuse easily (see the document, paragraph 0008, for example). This conventional battery pack therefore allows a user to easily replace the battery pack fuse connected in series to the battery unit (see this document, paragraph 0015, for example). EP 2 793 291 A2 discloses a rechargeable battery module which includes a plurality of rechargeable batteries, each of the rechargeable batteries including an electrode assembly including a positive electrode and a negative electrode, and a first electrode terminal and a second electrode terminal connected to the electrode assembly, and a bus bar electrically connecting the rechargeable batteries, the bus bar including a bus bar fuse part. Citation List Patent Literature Patent Literature 1 JP 2015-022959 A Summary of Invention Technical Problem To meet higher safety standards for battery packs, highly safety and more reliable protection of battery cells are required. The present disclosure provides a battery module having more improved safety than in the conventional battery pack and capable of protecting the battery cells more reliably, and provides a battery pack including the battery module. Solution to Problem The above cited problems are solved in accordance with the appended claims. In particular, a battery module including: a plurality of battery cells; a cell blocking portion in a current path inside each of the plurality of battery cells, the cell blocking portion being configured to interrupt the current path in response to a current of a predetermined current value or higher flowing through the current path; a pair of module terminals connected to the plurality of battery cells; and a module fuse connected in series to the pair of module terminals and the plurality of battery cells. A current value at which the cell blocking portion interrupts the current path is larger than a current value at which the module fuse blows out. Advantageous Effects of Invention The one aspect of the present disclosure provides a battery pack having more improved safety than in the conventional battery pack and capable of protecting the battery cells more reliably. Brief Description of Drawings Fig. 1 is a schematic circuit diagram of a battery pack according to one embodiment of the present disclosure.Fig. 2 is a graph showing the relationship between the current value I and the time T at the time of current interruption of a pack fuse, module fuses, and cell blocking portions of the battery pack shown in Fig. 1.Fig. 3 is a graph showing the relationship between the current value I and the time T at the time of current interruption of a pack fuse, module fuses, and cell blocking portions of the battery pack shown in Fig. 1.Fig. 4 is an external perspective view of a battery module according to one embodiment of the present disclosure.Fig. 5 is an exploded perspective view of the battery module in Fig. 4.Fig. 6 is a perspective view of a bus bar connecting the battery cells of the battery module shown in Fig. 5.Fig. 7 is a perspective view of a bus bar making up a module terminal of the battery module in Fig. 4.Fig. 8 is a perspective view of a battery cell making up the battery module shown in Fig. 5.Fig. 9 is an exploded perspective view of the battery cell in Fig. 8.Fig. 10 is an enlarged cross-sectional view of the battery cell taken along the line X-X of Fig. 8.Fig. 11 is an exploded perspective view of a current interruption valve shown in Fig. 10.Fig. 12 is an exploded perspective view of a storage element of the battery cell shown in Fig. 9. Description of Embodiments The following describes one e