Battery pack

Abstract

To improve waterproofness of a ventilation part provided in a case, by a relatively simple configuration.SOLUTION: A battery pack includes: a case; a battery cell that is provided within the case; a ventilation member that is provided via a seal part in a side wall part of the case and that adjusts pressure within the case; and a pressure release valve that is provided in an upper wall part of the case and that releases pressure to the outside of the case when the pressure within the case rises rapidly. The case has the side wall part provided with an enclosure wall for enclosing the seal part.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a battery pack. [Background technology]

[0002] The following Patent Document 1 relates to an energy storage device in which the lid of an exterior body that houses an energy storage element is provided with a ventilation chamber that connects the inside and outside of the exterior body, and discloses a technology in which the force of water that flows into the ventilation chamber can be weakened by providing multiple walls inside the ventilation chamber, and the water that flows into the ventilation chamber can be efficiently discharged by providing gaps between the multiple walls. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-152164 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technique of Patent Document 1 requires providing multiple walls within the ventilation chamber and providing gaps between the multiple walls, making it difficult to form the ventilation chamber. [Means for solving the problem]

[0005] In order to solve the above-mentioned problems, a battery pack according to one embodiment includes a case, a battery cell provided inside the case, a ventilation member provided on the side wall of the case via a sealing portion for adjusting the pressure inside the case, and a pressure release valve provided on the top wall of the case for releasing the pressure inside the case to the outside when the pressure inside the case suddenly increases, and the case has an enclosure wall on the side wall that surrounds the sealing portion. [Effects of the Invention]

[0006] According to one embodiment of the battery pack, the waterproofing of the ventilation section of the case can be improved with a relatively simple configuration. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a partially enlarged perspective view of a battery pack according to an embodiment; [Figure 2] 1 is a cross-sectional view of a battery pack according to an embodiment; [Figure 3] An enlarged view of a recessed portion provided in a battery pack according to an embodiment. [Figure 4] FIG. 1 is an enlarged cross-sectional view of a battery pack according to an embodiment; DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] Fig. 1 is a partially enlarged perspective view of a battery pack 100 according to an embodiment. Fig. 2 is a cross-sectional view of the battery pack 100 according to an embodiment. Fig. 3 is an enlarged view of a recess 113 provided in the battery pack 100 according to an embodiment. Fig. 4 is a partially enlarged cross-sectional view of the battery pack 100 according to an embodiment.

[0010] A battery pack 100 according to one embodiment is mounted on a vehicle equipped with a drive motor, such as a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHV), a fuel cell electric vehicle (FCV), or an electric vehicle (EV), and is used as a power supply source that supplies power to the drive motor.

[0011] As shown in FIGS. 1 to 4, a battery pack 100 according to one embodiment includes a case 110, a battery cell 120, a vent 130, and a pressure release valve 140.

[0012] The case 110 is a container-shaped member. The case 110 has an upper cover 111 and a lower case 112. The lower case 112 is a container-shaped member with an upper opening. The battery cells 120 are housed inside the lower case 112. The upper cover 111 is attached to the upper opening of the lower case 112 to close the upper opening of the lower case 112 and form a substantially horizontal upper wall portion (upper outer wall portion) of the case 110. The lower case 112 has a side wall portion 112A. As shown in FIG. 4 , the side wall portion 112A is inclined outward and downward at a predetermined inclination angle θ with respect to a vertical plane. A resin component 112B is attached to the outer surface of the side wall portion 112A. A recessed portion 113 that is recessed toward the inside of the case 110 is formed in the component 112B. A ventilation portion 130 is provided within the recessed portion 113. Two openings 113B are formed in the inner bottom surface 113A of the recess 113. A breathing membrane 131 is fitted into each of the two openings 113B from the outside. This allows the inner wall surface 113C of the recess 113 to function as an "enclosing wall" that surrounds the sealing portion 132 of the breathing membrane 131.

[0013] The battery cells 120 are provided inside the case 110. The battery cells 120 store power. The battery cells 120 are so-called rechargeable batteries. The battery cells 120 can supply high-voltage power. For example, nickel-metal hydride batteries, lithium-ion batteries, etc. are used as the battery cells 120. The battery pack 100 includes a plurality of battery cells 120 inside the lower case 112. The plurality of battery cells 120 are electrically connected in series by bus bars (not shown).

[0014] The ventilation section 130 is provided in the side wall section 112A of the case 110 and in the recessed section 113. The ventilation section 130 has a breathing membrane 131. The breathing membrane 131 is an example of a "ventilation member." The breathing membrane 131 is fitted into an opening 113B formed in the inner bottom surface 113A of the recessed section 113 and adjusts the pressure inside the case 110 by allowing breathing between the outside and the inside of the case 110. The breathing membrane 131 has an elastic, annular sealing section 132. The sealing section 132 seals the opening 113B by being compressed between the breathing membrane 131 and the periphery of the opening 113B. The sealing section 132 may be formed integrally with the breathing membrane 131 or may be a separate member (i.e., a sealing member) from the breathing membrane 131. In this embodiment, the battery pack 100 includes two breathing membranes 131 that fit into the two openings 113B formed in the deepest bottom surface 113A of the recess 113, respectively. However, this is not limiting, and the battery pack 100 may include one or three or more breathing membranes 131. Note that, because the side wall 112A is inclined downward, the breathing membrane 131 is provided in the recess 113 facing diagonally downward. As shown in FIGS. 3 and 4 , the ventilation portion 130 has a lid 133. The lid 133 is a flat member provided in the recess 113. The lid 133 is fixed in the recess 113 with screws 134 in a state in which the breathing membrane 131 is pressed from the outside.

[0015] The pressure release valve 140 is provided on the upper cover 111 of the case 110. When the pressure inside the case 110 suddenly increases, the pressure release valve 140 releases the pressure to the outside of the case 110. As shown in FIG. 2 , the pressure release valve 140 is provided between the ventilation part 130 and the battery cell 120.

[0016] As described above, the battery pack 100 according to one embodiment comprises a case 110, a battery cell 120 provided inside the case 110, a breathing membrane 131 provided on the side wall portion 112A of the case 110 via a sealing portion 132 to adjust the pressure inside the case 110, and a pressure release valve 140 provided on the upper wall portion of the case 110 to release the pressure inside the case 110 to the outside of the case 110 when the pressure inside the case 110 suddenly increases, and the case 110 has an enclosing wall on the side wall portion 112A that surrounds the sealing portion 132.

[0017] As a result, in one embodiment of the battery pack 100, the sealing portion 132 is surrounded by an enclosing wall, so that when driving, high-pressure cleaning, etc., water splashed around the sealing portion 132 first hits the enclosing wall, thereby suppressing the force of the water acting on the sealing portion 132. By surrounding seal portion 132 with a wall, splashed water can hit a wall or the like to reduce the water pressure when the seal portion is exposed to water (water splashed on the seal portion while driving, or particularly water from high-pressure cleaning, etc.), compared to when the water hits seal portion 132 directly. Therefore, according to battery pack 100 of one embodiment, the waterproofness of ventilation portion 130 of case 110 can be improved with a relatively simple configuration.

[0018] In the battery pack 100 according to one embodiment, the breathing membrane 131 is provided on the inner bottom surface 113A of the recess 113 formed in the side wall 112A of the case 110, and the surrounding wall is the inner wall surface 113C of the recess 113.

[0019] As a result, the battery pack 100 according to one embodiment can be formed relatively easily without the surrounding wall protruding from the surroundings.

[0020] In the battery pack 100 according to one embodiment, the breathing film 131 is provided on the side wall 112A of the case 110 so as to face obliquely downward.

[0021] This makes it difficult for water to accumulate inside the surrounding wall in battery pack 100 according to one embodiment. As a result, battery pack 100 according to one embodiment makes it difficult for water pressure to be transmitted to seal portion 132, and can further improve the waterproofness of ventilation portion 130 provided in case 110.

[0022] In the battery pack 100 according to one embodiment, the pressure release valve 140 is provided between the breathing membrane 131 and the battery cell 120 .

[0023] As a result, in the battery pack 100 according to an embodiment, when high-temperature gas is generated and the pressure inside the case 110 rises suddenly, the high-temperature gas is preferentially discharged to the outside through the pressure release valve 140, thereby making it difficult for the high-temperature gas to reach the breathing membrane 131. Therefore, in the battery pack 100 according to an embodiment, when high-temperature gas is generated and the pressure inside the case 110 rises suddenly, the breathing membrane 131 can be protected from the high-temperature gas.

[0024] In addition, in one embodiment of the battery pack 100, the breathing membrane 131 is fitted from the outside into an opening 113B formed in the inner bottom surface 113A of the recessed portion 113, and the battery pack 100 further includes a lid 133 that presses the breathing membrane 131 from the outside.

[0025] As a result, the battery pack 100 according to the embodiment can prevent the breathing membrane 131 from falling off through the opening 113B due to the pressure inside the case 110. Therefore, the battery pack 100 according to the embodiment can prevent the sealing property of the seal portion 132 of the breathing membrane 131 from being reduced due to the pressure inside the case 110.

[0026] Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to these embodiments, and various modifications and changes are possible within the scope of the gist of the present invention described in the claims. [Explanation of symbols]

[0027] 100 battery packs 110 cases 111 Upper cover 112 Lower case 112A Side wall part 112B Parts 113 Recess 113A bottom 113B opening 113C Inner wall 120 battery cells 130 Ventilation section 131 Respiratory membrane 132 Seal part 133 Lid 134 screws 140 Pressure relief valve

Claims

1. Case and a battery cell provided inside the case; a ventilation member provided on a side wall of the case via a seal portion and adapted to adjust the pressure inside the case; a pressure release valve provided on the upper wall of the case, which releases the pressure inside the case to the outside when the pressure inside the case suddenly increases; Equipped with The case is The side wall portion has a surrounding wall that is provided outside the ventilation member and the seal portion and surrounds the ventilation member and the seal portion. A battery pack characterized by:

2. In the side wall portion, the ventilation member and the surrounding wall are provided obliquely downward.

2. The battery pack according to claim 1, wherein the battery pack is a battery pack having a plurality of electrodes.

3. The ventilation member and the sealing portion are provided at the bottom of a recessed portion of the side wall portion that is recessed from the surrounding area, The surrounding wall is an inner wall surface of the recessed portion.

2. The battery pack according to claim 1, wherein the battery pack is a battery pack having a plurality of electrodes.

4. A lid is provided fixedly within the recessed portion and presses down on the ventilation member from the outside.

4. The battery pack according to claim 3.

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