Patent Description:
The present invention relates to a battery module.

For example, <CIT> discloses a power supply device including: a battery stack formed by stacking a plurality of battery cells with a spacer being interposed therebetween; a gas duct disposed on an upper surface of the battery stack; and a top cover that covers and protects a bus bar and a circuit board connected to the battery stack. The top cover is attached to the gas duct using a set screw.

As disclosed in <CIT>, there has been known a battery module including: a plurality of stacked battery cells; and a cover body provided to cover the plurality of battery cells in order to protect a bus bar connected to the battery cells or the like. In such a battery module, a structure for attaching the cover body is required to be constructed in a simple manner in order to prevent an increased number of components of the battery module and a complicated operation of attaching the cover body.

Thus, it is an object of the present invention to solve the above-described problem and to provide a battery module to realize a structure for attaching a cover body with a simple configuration.

According to the battery module thus configured, the cylindrical portion and the projection provided at one end portion of the duct main body portion are used to attach the cover body, whereas the duct extension portion and the clip portion provided at the other end of the duct main body portion are used to attach the duct. Thus, respective structures for attaching the cover body and the duct can be each constructed in a simple manner.

Embodiments of the present invention will be described with reference to figures. It should be noted that in the figures referred to below, the same or corresponding members are denoted by the same reference characters.

<FIG> is a perspective view showing a battery module according to an embodiment of the present invention. <FIG> is an exploded assembly diagram showing the battery module in <FIG>. Each of <FIG> is a perspective view showing an internal structure of the battery module in <FIG>. <FIG> is a perspective view showing a battery cell unit included in the battery module in <FIG>. <FIG> is a perspective view showing a battery cell included in the battery cell unit in <FIG>.

Referring to <FIG>, a battery module <NUM> is used as a power supply for driving a vehicle such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or a battery electric vehicle (BEV).

In the present specification, for convenience of description of the structure of battery module <NUM>, the "Y axis" represents an axis extending in parallel with a stacking direction of a plurality of below-described battery cells <NUM>, the "X axis" represents an axis extending in a direction orthogonal to the Y axis, and the "Z axis" represents an axis extending in a direction orthogonal to the Y axis and the X axis. An obliquely rightward upward direction in the plane of sheet of <FIG> is "+Y axis direction", and an obliquely leftward downward direction in the plane of sheet of <FIG> is "-Y axis direction". An obliquely rightward downward direction in the plane of sheet of <FIG> is "+X axis direction" and an obliquely leftward upward direction in the plane of sheet of <FIG> is "-X axis direction". An upward direction in the plane of sheet of <FIG> is "+Z axis direction" and a downward direction in the plane of sheet of <FIG> is "-Z axis direction". Typically, battery module <NUM> is mounted on a vehicle in such a posture that the +Z axis direction corresponds to the upward direction and the -Z axis direction corresponds to the downward direction.

First, an overall structure of battery module <NUM> will be described. As shown in <FIG>, battery module <NUM> has a plurality of battery cell units <NUM> (21A, 21B, 21C, 21D, 21E, 21F).

The plurality of battery cell units <NUM> are arranged side by side in the Y axis direction. Battery cell unit 21A, battery cell unit 21B, battery cell unit 21C, battery cell unit 21D, battery cell unit 21E, and battery cell unit 21F are arranged side by side in this order from the negative side to the positive side in the Y axis direction. It should be noted that the number of battery cell units <NUM> included in battery module <NUM> is not particularly limited as long as two or more battery cell units <NUM> are included.

As shown in <FIG>, each of battery cell units <NUM>, i.e., each of battery cell units 21A to 21F includes a plurality of battery cells <NUM> and a case body <NUM>.

In each battery cell unit <NUM>, two battery cells <NUM> are arranged side by side continuously in the Y axis direction. The number of battery cells <NUM> included in each battery cell unit <NUM> is not particularly limited as long as a plurality of battery cells <NUM> are included.

Each of battery cells <NUM> is a lithium ion battery. Battery cell <NUM> has an output density of <NUM> W/L or more. Battery cell <NUM> has a prismatic shape and has a thin plate shape in the form of a rectangular parallelepiped. The plurality of battery cells <NUM> are stacked such that the Y axis direction corresponds to the thickness direction of each battery cell <NUM>.

Each of battery cells <NUM> has an exterior package <NUM>. Exterior package <NUM> is constituted of a housing having a rectangular parallelepiped shape, and forms the external appearance of battery cell <NUM>. An electrode assembly and an electrolyte solution are accommodated in exterior package <NUM>.

Exterior package <NUM> has a cell side surface <NUM>, a cell side surface <NUM>, and a cell top surface <NUM>. Each of cell side surface <NUM> and cell side surface <NUM> is constituted of a flat surface orthogonal to the Y axis direction. Cell side surface <NUM> and cell side surface <NUM> are oriented oppositely in the Y axis direction. Each of cell side surface <NUM> and cell side surface <NUM> has the largest area among the areas of the plurality of side surfaces of exterior package <NUM>. Cell top surface <NUM> is constituted of a flat surface orthogonal to the Z axis direction. Cell top surface <NUM> is oriented in the +Z axis direction.

Battery cell <NUM> further has a gas-discharge valve <NUM>. Gas-discharge valve <NUM> is provided in cell top surface <NUM>. Gas-discharge valve <NUM> is provided at the center portion of cell top surface <NUM> in the X axis direction. When internal pressure of exterior package <NUM> becomes more than or equal to a predetermined value due to gas generated inside exterior package <NUM>, gas-discharge valve <NUM> discharges the gas to the outside of exterior package <NUM>. The gas from gas-discharge valve <NUM> flows through a below-described duct <NUM> and is discharged to the outside of battery module <NUM>.

Battery cell <NUM> further has electrode terminals <NUM> that are a pair of a positive electrode terminal 16p and a negative electrode terminal 16n. Electrode terminals <NUM> are provided on cell top surface <NUM>. Positive electrode terminal 16p and negative electrode terminal 16n are provided on both sides with gas-discharge valve <NUM> being interposed therebetween in the X axis direction.

Case body <NUM> has a rectangular parallelepiped appearance. Case body <NUM> is composed of a resin. In each battery cell unit <NUM>, case body <NUM> accommodates a plurality of battery cells <NUM>. Case body <NUM> has a case top portion <NUM>. Case top portion <NUM> has a wall shape having a thickness direction corresponding to the Z axis direction with case top portion <NUM> being disposed in parallel with the X-Y axes plane.

As shown in <FIG>, the plurality of battery cells <NUM> are stacked in the Y axis direction across battery cell units 21A to 21F arranged side by side in the Y axis direction. The plurality of battery cells <NUM> are stacked such that cell side surfaces <NUM> of battery cells <NUM> adjacent to each other in the Y axis direction face each other and cell side surfaces <NUM> of battery cells <NUM> adjacent to each other in the Y axis direction face each other. Thus, positive electrode terminals 16p and negative electrode terminals 16n are alternately arranged in the Y axis direction in which the plurality of battery cells <NUM> are stacked. Positive electrode terminal 16p and negative electrode terminal 16n adjacent to each other in the Y axis direction are connected to each other by a bus bar (not shown) disposed in case top portion <NUM>. Thus, the plurality of battery cells <NUM> are electrically connected together in series.

As shown in <FIG>, battery module <NUM> further has a pair of end plates <NUM> (42P, 42Q) and a pair of binding bars <NUM>. The pair of binding bars <NUM> and the pair of end plates <NUM> collectively hold the plurality of battery cell units <NUM> (the plurality of battery cells <NUM>) arranged side by side in the Y axis direction.

The pair of end plates <NUM> are disposed at both ends beside the plurality of battery cells <NUM> (the plurality of battery cell units <NUM>) in the Y axis direction. End plate 42P faces battery cell unit 21A in the Y axis direction, and end plate 42Q faces battery cell unit 21F in the Y axis direction.

Each of end plates <NUM> has a plate portion <NUM> and a roof portion <NUM>. Plate portion <NUM> has a plate shape having a thickness direction corresponding to the Y axis direction. Roof portion <NUM> extends, from an end portion (upper end portion) of plate portion <NUM> in the +Z axis direction, in a direction away from the stack of battery cells <NUM> in the Y axis direction. Roof portion <NUM> has a roof shape having a thickness in the Z axis direction and extending in the form of a strip along the upper end portion of plate portion <NUM>.

The pair of binding bars <NUM> are disposed at both ends of the stack of battery cells <NUM> in the X axis direction. Each of binding bars <NUM> extends in the Y axis direction. An end portion of binding bar <NUM> in the -Y axis direction is connected to end plate 42P. An end portion of binding bar <NUM> in the +Y axis direction is connected to end plate 42Q. The pair of binding bars <NUM> and the pair of end plates <NUM> apply a restraint force in the Y axis direction onto the plurality of battery cells <NUM> (the plurality of battery cell units <NUM>).

Battery module <NUM> further has duct <NUM> and a cover body <NUM>. Duct <NUM> is composed of a resin. Duct <NUM> extends in the Y axis direction with duct <NUM> facing the plurality of battery cells <NUM> (the plurality of battery cell units <NUM>) in the Z axis direction. Duct <NUM> forms a path through which gas discharged from each of the plurality of battery cells <NUM> flows. Duct <NUM> is attached to an attachment-target member <NUM>. Attachment-target member <NUM> is a member held by battery cells <NUM>, and, in the present embodiment, is constituted of the plurality of case bodies <NUM> arranged side by side in the Y axis direction. The duct according to the present invention is not limited to the above, and may be attached to a separator interposed between the battery cells stacked in the Y axis direction.

Cover body <NUM> is composed of a resin. Cover body <NUM> is provided to cover the plurality of battery cells <NUM> in the Z axis direction. Cover body <NUM> is provided to face case top portions <NUM> of case bodies <NUM> in the Z axis direction. Cover body <NUM> is provided to further cover duct <NUM>.

Cover body <NUM> is detachably attached to duct <NUM>. Hereinafter, a structure for attaching cover body <NUM> to duct <NUM> will be described.

Referring to <FIG> and <FIG>, cover body <NUM> has a flat plate portion <NUM> and an edge portion <NUM>. Flat plate portion <NUM> has a thickness in the Z axis direction and is disposed in parallel with the X-Y axes plane orthogonal to the Z axis direction. Flat plate portion <NUM> has a quadrangular shape as a whole when viewed in a plan view. Flat plate portion <NUM> is provided to face the plurality of battery cells <NUM> (the plurality of battery cell units <NUM>) in the Z axis direction. Edge portion <NUM> extends in the -Z axis direction from a peripheral edge portion of flat plate portion <NUM>. Edge portion <NUM> has a height in the Z axis direction and intermittently extends along the peripheral edge portion of flat plate portion <NUM>.

Each of <FIG> and <FIG> is a perspective view showing the duct. <FIG> is a side view showing the battery module when viewed in a direction indicated by an arrow IX in <FIG>. <FIG> is a perspective view showing a step of attaching the cover body to the duct.

Referring to <FIG> and <FIG>, duct <NUM> has a duct main body portion <NUM> and a duct extension portion <NUM>. Duct main body portion <NUM> forms a main part of duct <NUM> for allowing gas from each battery cell <NUM> to flow therethrough. Duct main body portion <NUM> extends in the Y axis direction with duct main body portion <NUM> facing, in the Z axis direction, the plurality of gas-discharge valves <NUM> arranged side by side with a space being interposed therebetween in the Y axis direction. Duct extension portion <NUM> extends in the +Y axis direction from the end portion of duct main body portion <NUM> in the +Y axis direction. Duct extension portion <NUM> has a shape of plate disposed in parallel with the X-Y axes plane.

Referring to <FIG> and <FIG> as well as <FIG>, duct <NUM> further has a cylindrical portion <NUM> and a pair of projections <NUM> (<NUM>, <NUM>1T).

Cylindrical portion <NUM> extends, in the -Y axis direction in the form of a cylinder, from the end portion of duct main body portion <NUM> in the -Y axis direction so as to have a tip with an opening. Duct main body portion <NUM> is provided between duct extension portion <NUM> and cylindrical portion <NUM> in the Y axis direction. Cylindrical portion <NUM> communicates with a flow space <NUM>, which will be described later. As shown in <FIG>, a hose H for discharging gas from each of battery cells <NUM> is fitted to cylindrical portion <NUM>.

Each of projections <NUM> is provided at a position away from the opening of cylindrical portion <NUM> in the +Y axis direction. Projection <NUM> protrudes from outer peripheral surface 73a of cylindrical portion <NUM>. Projection <NUM> has a thickness in the Z axis direction and extends in the Y axis direction in the form of a rib. An end portion of projection <NUM> in the +Y axis direction is connected to duct main body portion <NUM> (a duct side wall portion 141P described later). The pair of projections <NUM> are symmetrically provided with respect to the Y-Z axes plane including the central axis of cylindrical portion <NUM>. Projection <NUM> is provided at a position away from projection 271T in the +X axis direction. Each of projections <NUM> is provided such that an end portion of hose H fitted to cylindrical portion <NUM> can be brought into abutment therewith.

As shown in <FIG> and <FIG>, a notch portion <NUM> is provided in an edge portion 236P of edge portions <NUM> of cover body <NUM>, edge portion 236P being along the peripheral edge portion of the end portion of flat plate portion <NUM> in the -Y axis direction. In a state in which cover body <NUM> is attached to duct <NUM>, cylindrical portion <NUM> and the pair of projections <NUM> are disposed in notch portion <NUM>.

Cover body <NUM> further has a pair of anchoring portions <NUM> (<NUM>, 241T). The pair of anchoring portions <NUM> can be respectively anchored to the pair of projections <NUM> in the Z axis direction.

Each of anchoring portions <NUM> has an arm portion <NUM> and a claw portion <NUM>. Arm portion <NUM> extends in the -Z axis direction from the peripheral edge portion of flat plate portion <NUM>. When viewed in the Y axis direction, arm portion <NUM> is provided to partially overlap with a portion of edge portion <NUM> notched by notch portion <NUM>. An end portion of arm portion <NUM> in the +Z axis direction forms a fixed end supported by flat plate portion <NUM>, and an end portion of arm portion <NUM> in the -Z axis direction forms a free end. Arm portion <NUM> is elastically deformable with respect to the fixed end thereof in a direction away from outer peripheral surface 73a of cylindrical portion <NUM>. Claw portion <NUM> protrudes, in a direction toward outer peripheral surface 73a of cylindrical portion <NUM>, from the tip portion of arm portion <NUM> in the -Z axis direction.

When attaching cover body <NUM> to duct <NUM>, cover body <NUM> is disposed just above duct <NUM> and is slid toward duct <NUM> in the -Z axis direction. On this occasion, claw portions <NUM> of the pair of anchoring portions <NUM> are respectively brought into abutment with the pair of projections <NUM> in the Z axis direction, with the result that arm portions <NUM> are each elastically deformed in the direction away from outer peripheral surface 73a of cylindrical portion <NUM>. When cover body <NUM> is further slid in the -Z axis direction, claw portions <NUM> climb over projections <NUM>. Arm portions <NUM> are each restored in the direction toward outer peripheral surface 73a of cylindrical portion <NUM>, with the result that claw portions <NUM> are anchored to projections <NUM> in the Z axis direction.

In the present embodiment, the pair of projections <NUM> on the duct <NUM> side and the pair of anchoring portions <NUM> on the cover body <NUM> side are respectively anchored to each other, with the result that cover body <NUM> is attached to duct <NUM>. According to such a configuration, since projections <NUM>, which are included in duct <NUM> for the purpose of abutment with the hose in the first place, are used, the structure for attaching cover body <NUM> can be constructed in a simple manner.

Next, a structure for attaching duct <NUM> to attachment-target member <NUM> (the plurality of case bodies <NUM>) will be described.

Referring to <FIG> and <FIG>, attachment-target member <NUM> (the plurality of case bodies <NUM>) has a floor wall portion <NUM> and a pair of vertical wall portions <NUM> (<NUM>, 116T).

Floor wall portion <NUM> is constituted of a portion of case top portion <NUM> of each case body <NUM>. Floor wall portion <NUM> is disposed in parallel with the X-Y axes plane. Floor wall portion <NUM> has a wall shape having a thickness in the Z axis direction and extending in the Y axis direction across the plurality of case bodies <NUM> arranged side by side in the Y axis direction. Floor wall portion <NUM> is disposed just above each of cell top surfaces <NUM> of battery cells <NUM> accommodated in case bodies <NUM>. Floor wall portion <NUM> is disposed between positive electrode terminals 16p and negative electrode terminals 16n in the X axis direction. Floor wall portion <NUM> is provided with through holes <NUM> to expose gas-discharge valves <NUM>.

The pair of vertical wall portions <NUM> rise from floor wall portion <NUM> in the +Z axis direction. An end portion (lower end portion) of each vertical wall portion <NUM> in the -Z axis direction is connected to floor wall portion <NUM>. Vertical wall portion <NUM> has a wall shape having a thickness in the X axis direction and extending in the Y axis direction with an unchanged height in the Z axis direction across the plurality of case bodies <NUM> arranged side by side in the Y axis direction.

The pair of vertical wall portions <NUM> are provided with a space being interposed therebetween in the X axis direction. Vertical wall portion <NUM> is provided at a position away from vertical wall portion 116T in the +X axis direction. The pair of vertical wall portions <NUM> are provided at the center portions of case top portions <NUM> in the X axis direction. Through holes <NUM> are opened between vertical wall portion <NUM> and vertical wall portion 116T in the X axis direction. In a state in which duct <NUM> is not attached to attachment-target member <NUM>, a space surrounded in three directions by floor wall portion <NUM>, vertical wall portion <NUM>, and vertical wall portion 116T is opened in the +Z axis direction and the ±Y axis direction.

<FIG> is a cross sectional view showing the battery module (state in which the duct is attached to the attachment-target member) when viewed in a direction of an arrow on a line XI-XI in <FIG>.

Referring to <FIG>, <FIG> and <FIG>, duct main body portion <NUM> is disposed between the pair of vertical wall portions <NUM>. Duct main body portion <NUM> and case bodies <NUM> form flow space <NUM> for gas discharged from each battery cell <NUM>.

Duct main body portion <NUM> has a duct top wall portion <NUM>, a pair of duct side wall portions <NUM> (<NUM>, 131T), and a pair of duct side wall portions <NUM> (141P, 141Q).

Duct top wall portion <NUM> is disposed in parallel with the X-Y axes plane. Duct top wall portion <NUM> has a wall shape having a thickness in the Z axis direction and extending in the Y axis direction with an unchanged width in the X axis direction. Duct top wall portion <NUM> faces floor wall portion <NUM> with flow space <NUM> being interposed therebetween in the Z axis direction. Flow space <NUM> is formed between duct top wall portion <NUM> and floor wall portion <NUM> in the Z axis direction.

The pair of duct side wall portions <NUM> extend, in the Z axis direction toward floor wall portion <NUM> (in the -Z axis direction), from both end portions of duct top wall portion <NUM> in the X axis direction. Each of duct side wall portions <NUM> has a wall shape having a thickness in the X axis direction and extending in the Y axis direction with an unchanged height in the Z axis direction. The pair of duct side wall portions <NUM> are provided with a space being interposed therebetween in the X axis direction. Duct side wall portion <NUM> is provided at a position away from duct side wall portion 131T in the +X axis direction. Flow space <NUM> is formed between duct side wall portion <NUM> and duct side wall portion 131T in the X axis direction.

Duct side wall portion <NUM> faces vertical wall portion <NUM> in the X axis direction. Duct side wall portion 131T faces vertical wall portion 116T in the X axis direction. A space is provided between duct side wall portion <NUM> and vertical wall portion <NUM> in the X axis direction. A space is provided between duct side wall portion 131T and vertical wall portion 116T in the X axis direction. The size of each of these spaces may be such a size that leakage of a small amount of gas from flow space <NUM> is permitted.

Each of duct side wall portions <NUM> is disposed in parallel with the X-Z axes plane. The pair of duct side wall portions <NUM> are provided with a space being interposed therebetween in the Y axis direction. The pair of duct side wall portions <NUM> are connected to both end portions of duct top wall portion <NUM> and both end portions of each of the pair of duct side wall portions <NUM> in the Y axis direction.

Duct side wall portion 141P is provided at a position away from duct side wall portion 141Q in the -Y axis direction. Flow space <NUM> is formed between duct side wall portion 141P and duct side wall portion 141Q in the Y axis direction. Duct side wall portion <NUM> has a wall shape having a thickness in the Y axis direction and extending in the X axis direction with an unchanged height in the Z axis direction.

Each of <FIG> and <FIG> is a side view showing a step when attaching the duct to the attachment-target member. Referring to <FIG>, <FIG>, and <FIG>, each vertical wall portion <NUM> of attachment-target member <NUM> (the plurality of case bodies <NUM>) has claw portions <NUM>. Each of claw portions <NUM> has a protruding shape protruding in the X axis direction.

Claw portions <NUM> are provided in each of vertical wall portions <NUM>, i.e., vertical wall portion <NUM> and vertical wall portion 116T. Each of claw portions <NUM> is provided in vertical wall portion <NUM> to protrude toward duct side wall portion <NUM> from the inner surface of vertical wall portion <NUM> facing duct side wall portion <NUM> in the X axis direction. Each of claw portions <NUM> is provided in vertical wall portion 116T to protrude toward duct side wall portion 131T from the inner surface of vertical wall portion 116T facing duct side wall portion 131T in the X axis direction.

Claw portions <NUM> are provided at the upper end portion of each vertical wall portion <NUM>. The plurality of claw portions <NUM> are provided in each vertical wall portion <NUM> with a space being interposed therebetween in the Y axis direction. The plurality of claw portions <NUM> are provided such that claw portions <NUM> of vertical wall portion <NUM> and claw portions <NUM> of vertical wall portion 116T face each other in the X axis direction.

As shown in <FIG>, in each case body <NUM> of attachment-target member <NUM>, vertical wall portion <NUM> is provided with a first protrusion 121P and a second protrusion 121Q. First protrusion 121P and second protrusion 121Q are provided at both end portions of case body <NUM> in the Y axis direction. Each of first protrusion 121P and second protrusion 121Q has a protruding shape protruding in the X axis direction.

As shown in <FIG> and <FIG>, when the plurality of case bodies <NUM> are arranged side by side in the Y axis direction, respective first protrusions 121P and second protrusions 121Q of adjacent case bodies <NUM> in the Y axis direction are connected together in the Y axis direction, thereby forming claw portions <NUM>.

In <FIG> and <FIG>, respective case bodies <NUM> of battery cell unit 21A, battery cell unit 21B, battery cell unit 21C, battery cell unit 21D, battery cell unit 21E, and battery cell unit 21F are shown as a case body 31A, a case body 31B, a case body 31C, a case body 31D, a case body 31E, and a case body 31F, respectively. For example, first protrusion 121P provided in case body 31C and second protrusion 121Q provided in case body 31D adjacent to case body 31C are connected to each other in the Y axis direction to form a claw portion <NUM>.

On the other hand, at the end portion of vertical wall portion <NUM> in the -Y axis direction, first protrusion 121P provided in case body 31A is disposed solely. At the end portion of vertical wall portion <NUM> in the +Y axis direction, second protrusion 121Q provided in case body 31F is disposed solely to form a claw portion <NUM>.

Referring to <FIG>, <FIG>, and <FIG>, groove portions <NUM> are provided in each duct side wall portion <NUM> of duct <NUM>. Each of groove portions <NUM> has a recessed shape recessed in the X axis direction.

Groove portions <NUM> are provided in each of duct side wall portions <NUM>, i.e., duct side wall portion <NUM> and duct side wall portion 131T. Duct side wall portion <NUM> is provided with groove portions <NUM> each recessed from the outer surface of duct side wall portion <NUM> facing vertical wall portion <NUM> in the X axis direction so as to be separated away from vertical wall portion <NUM>. Duct side wall portion 131T is provided with groove portions <NUM> each recessed from the outer surface of duct side wall portion 131T facing vertical wall portion 116T in the X axis direction so as to be separated away from vertical wall portion 116T.

The plurality of groove portions <NUM> are formed in each duct side wall portion <NUM> with a space being interposed therebetween in the Y axis direction. The plurality of groove portions <NUM> are provided such that groove portions <NUM> of duct side wall portion <NUM> and groove portions <NUM> of duct side wall portion 131T face each other in the X axis direction. The plurality of groove portions <NUM> are provided to respectively correspond to the plurality of claw portions <NUM> provided in vertical wall portion <NUM>. With such a configuration, respective sets of claw portions <NUM> and groove portions <NUM> are provided at a plurality of positions with a space being interposed therebetween in the Y axis direction.

Each of duct side wall portions <NUM> (<NUM>, 131T) is further provided with a groove portion <NUM>. Groove portion <NUM> is provided at the end portion of duct side wall portion <NUM> in the -Y axis direction. The recessed shape of groove portion <NUM> is opened in the +Z axis direction and the -Y axis direction.

Each of groove portions <NUM> has a first segment portion <NUM> and a second segment portion <NUM>. First segment portion <NUM> extends in the Y axis direction. In a state in which duct <NUM> is attached to attachment-target member <NUM> (the plurality of case bodies <NUM>), claw portion <NUM> is disposed in first segment portion <NUM>. First segment portion <NUM> anchors claw portion <NUM> in the Z axis direction.

First segment portion <NUM> extends in the Y axis direction along the end portion (upper end portion) of duct side wall portion <NUM> in the +Z axis direction. First segment portion <NUM> has a recessed shape forming a step in the X axis direction with respect to the outer surface of duct side wall portion <NUM> at its end portion in the -Z axis direction and extending in the Y axis direction as its longitudinal direction.

Second segment portion <NUM> extends in a direction intersecting the Y axis direction and is connected to first segment portion <NUM>. Second segment portion <NUM> extends in the Z axis direction orthogonal to the Y axis direction. Second segment portion <NUM> has a recessed shape forming steps with respect to the outer surface of duct side wall portion <NUM> at its both end portions in the Y axis direction and extending in the Z axis direction as its longitudinal direction. The end portion (upper end portion) of second segment portion <NUM> in the +Z axis direction and the end portion of first segment portion <NUM> in the -Y axis direction are connected to each other. First segment portion <NUM> extends in the +Y axis direction from a position at which first segment portion <NUM> and second segment portion <NUM> are connected to each other. Second segment portion <NUM> allows claw portion <NUM> to enter first segment portion <NUM> when attaching duct <NUM> to attachment-target member <NUM>.

The length of first segment portion <NUM> in the Y axis direction is preferably <NUM>/<NUM> or less, more preferably <NUM>/<NUM> or less, and further preferably <NUM>/<NUM> or less of the total length of duct side wall portion <NUM> in the Y axis direction.

Duct side wall portion <NUM> has a stepped portion <NUM>. Stepped portion <NUM> is provided in at least one groove portion <NUM> of the plurality of groove portions <NUM>.

Stepped portion <NUM> is provided on a path of first segment portion <NUM>. Stepped portion <NUM> is provided between the end portion of first segment portion <NUM> in the +Y axis direction and the end portion of first segment portion <NUM> in the -Y axis direction. Stepped portion <NUM> has a stepped shape rising from the bottom surface of groove portion <NUM>. More specifically, based on the bottom surface of groove portion <NUM> as a reference, stepped portion <NUM> is constituted of: a top surface having the same height as the outer surface of duct side wall portion <NUM> in the X axis direction; an inclined surface extending obliquely with respect to the Y-X axes plane between the end portion of the top surface in the -Y axis direction and the bottom surface of groove portion <NUM>; and a right-angled surface extending in parallel with the X-Z axes plane between the end portion of the top surface in the +Y axis direction and the bottom surface of groove portion <NUM>.

In a state in which duct <NUM> is attached to attachment-target member <NUM>, claw portion <NUM> is disposed opposite to second segment portion <NUM> with stepped portion <NUM> being interposed therebetween on the path of first segment portion <NUM>. Claw portion <NUM> is disposed between the end portion of first segment portion <NUM> in the +Y axis direction and stepped portion <NUM>.

<FIG> is a perspective view showing the battery module when viewed in a direction indicated by an arrow XIV in <FIG>. Referring to <FIG>, <FIG>, and <FIG>, duct <NUM> further has a clip portion <NUM>.

Clip portion <NUM> extends in the -Y axis direction from duct extension portion <NUM>. Clip portion <NUM> has a bar shape having a thickness in the Z axis direction and extending in the Y axis direction with an unchanged width in the X axis direction. An end portion of clip portion <NUM> in the +Y axis direction is connected to duct extension portion <NUM>. Clip portion <NUM> is elastically deformable such that the end portion of clip portion <NUM> in the -Y axis direction is displaced along the Z axis direction with respect to a position connected to duct extension portion <NUM>.

As shown in <FIG>, in a state in which duct <NUM> is attached to attachment-target member <NUM>, clip portion <NUM> and duct extension portion <NUM> sandwich end plate 42Q in the Z axis direction. Roof portion <NUM> of end plate 42Q is sandwiched between duct extension portion <NUM> and clip portion <NUM> in the Z axis direction.

Referring to <FIG> and <FIG>, when attaching duct <NUM> to attachment-target member <NUM>, duct <NUM> is first disposed to face attachment-target member <NUM> such that the plurality of claw portions <NUM> respectively face second segment portions <NUM> of the plurality of groove portions <NUM> in the Z axis direction.

Next, duct <NUM> is slid in the -Z axis direction indicated by an arrow <NUM> in <FIG> and is accordingly disposed between the pair of vertical wall portions <NUM> (<NUM>, 116T). On this occasion, each of the plurality of claw portions <NUM> enters a corresponding one of the plurality of second segment portions <NUM>, and is moved through second segment portion <NUM> to the position at which first segment portion <NUM> and second segment portion <NUM> are connected to each other (position at which claw portion <NUM> is indicated by a chain double-dashed line in <FIG>). Further, first protrusion 121P provided in case body 31A is positioned to face groove portion <NUM> in the Y axis direction, and roof portion <NUM> of end plate 42Q is positioned to face a space between clip portion <NUM> and duct extension portion <NUM> in the Y axis direction.

Next, duct <NUM> is slid in the -Y axis direction indicated by an arrow <NUM> in <FIG>. On this occasion, each of the plurality of claw portions <NUM> is moved through first segment portion <NUM> to a position away in the +Y axis direction from the position at which first segment portion <NUM> and second segment portion <NUM> are connected to each other. Further, in groove portion <NUM> provided with stepped portion <NUM>, claw portion <NUM> climbs over stepped portion <NUM> during the movement in first segment portion <NUM>. Claw portion <NUM> disposed in first segment portion <NUM> is brought into abutment with the stepped portion in the X axis direction as formed by first segment portion <NUM> and the outer surface of duct side wall portion <NUM>, and is accordingly anchored in the Z axis direction.

First protrusion 121P provided in case body 31A is disposed in groove portion <NUM>. First protrusion 121P disposed in groove portion <NUM> is brought into abutment with the stepped portion in the X axis direction as formed by groove portion <NUM> and the outer surface of duct side wall portion <NUM>, and is accordingly anchored in the Z axis direction. Roof portion <NUM> of end plate 42Q is inserted between clip portion <NUM> and duct extension portion <NUM>.

With the above steps, the operation of attaching duct <NUM> to attachment-target member <NUM> is completed. It should be noted that when detaching duct <NUM> from attachment-target member <NUM>, the above steps may be performed in the reverse order.

In the present embodiment, cylindrical portion <NUM> and the pair of projections <NUM> provided at the end portion of duct main body portion <NUM> in the -Y axis direction are used to attach cover body <NUM>, and duct extension portion <NUM> and clip portion <NUM> provided at the end portion of duct main body portion <NUM> in the +Y axis direction are used to attach duct <NUM>. Thus, the respective structures for attaching cover body <NUM> and duct <NUM> can be constructed in a simple manner.

The above-described structure of battery module <NUM> according to the embodiment of the present invention is summarized as follows. Battery module <NUM> according to the present embodiment includes: the plurality of battery cells <NUM> stacked in the Y axis direction (first direction); cover body <NUM> provided to cover the plurality of battery cells <NUM> in the Z axis direction (second direction) orthogonal to the Y axis direction; and duct <NUM> through which the gas discharged from each of the plurality of battery cells <NUM> flows. Duct <NUM> has: duct main body portion <NUM> disposed between each of the plurality of battery cells <NUM> and cover body <NUM> in the Z axis direction and extending in the Y axis direction to form flow space <NUM> for the gas; cylindrical portion <NUM> to which hose H is able to be fitted, cylindrical portion <NUM> extending, in the Y axis direction in a form of a cylinder, from one end portion of duct main body portion <NUM> in the Y axis direction so as to have a tip with an opening; and projection <NUM> with which the end portion of hose H fitted to cylindrical portion <NUM> is able to be brought into abutment, projection <NUM> protruding from outer peripheral surface 73a of cylindrical portion <NUM> at a position away from the opening of cylindrical portion <NUM> in the Y direction. Cover body <NUM> has anchoring portion <NUM> anchored to projection <NUM> in the Z axis direction.

According to battery module <NUM> of the embodiment of the present invention thus configured, the structure for attaching cover body <NUM> to duct <NUM> can be constructed in a simple manner.

Claim 1:
A battery module comprising:
a plurality of battery cells (<NUM>) stacked in a first direction;
a cover body (<NUM>) provided to cover the plurality of battery cells (<NUM>) in a second direction orthogonal to the first direction; and
a duct (<NUM>) through which gas discharged from each of the plurality of battery cells (<NUM>) flows, wherein
the duct (<NUM>) has
a duct main body portion (<NUM>) disposed between each of the plurality of battery cells (<NUM>) and the cover body (<NUM>) in the second direction and extending in the first direction to form a flow space (<NUM>) for the gas,
a cylindrical portion (<NUM>) to which a hose is able to be fitted, the cylindrical portion (<NUM>) extending, in the first direction in a form of a cylinder, from one end portion of the duct main body portion (<NUM>) in the first direction so as to have a tip with an opening, characterized in
a projection (<NUM>) with which an end portion of the hose fitted to the cylindrical portion (<NUM>) is able to be brought into abutment, the projection (<NUM>) protruding from an outer peripheral surface (73a) of the cylindrical portion (<NUM>) at a position away from the opening of the cylindrical portion (<NUM>) in the first direction, and
the cover body (<NUM>) has an anchoring portion (<NUM>) anchored to the projection (<NUM>) in the second direction.