Battery pack

Abstract

The battery pack is mounted on (eVTOL). A battery pack is provided with a battery cell (30) and a cold storage member (40) that cools the battery cell (30). The cold storage member (40) has: a support body (41) having a wall (411) that defines a gap (412); a cold storage material (42) disposed in the gap (412) and supported by the support body (41); and a beam (43) bridging the wall (411). The support body (41) and the beam (43) are formed using a material having better thermal conductivity than the cold storage material (42).

Description

[0001] Cross-reference to related applications

[0002] This application is based on patent application No. 2022-182748 filed in Japan on November 15, 2022, and the contents of the basic application are incorporated herein by reference in their entirety. Technical Field

[0003] The disclosure in this specification relates to a battery pack mounted on an electric vehicle. Background Art

[0004] Patent Document 1 discloses a battery pack mounted on an electric vehicle. As an explanation of technical elements in this specification, the contents of the prior art documents are cited by reference.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2020-170584

[0008] The battery pack disclosed in Patent Document 1 includes a battery cell and a cold storage material. The cold storage material is arranged in contact with the battery cell. The cold storage material is a latent heat cold storage material that absorbs the heat of the battery cell by utilizing a phase change from a solid phase to a liquid phase. However, since the thermal conductivity of the cold storage material is low, it is difficult for heat to be transferred to the inside of the cold storage material simply by bringing the cold storage material into contact with the battery cell. From the above viewpoints or other viewpoints not mentioned, further improvements to the battery pack are required. Summary of the invention

[0009] One object of the disclosure is to provide a battery pack with high heat dissipation performance.

[0010] A disclosed battery pack is mounted on an electric vehicle and includes:

[0011] Battery cells; and

[0012] a cold storage component that cools the battery cells,

[0013] The cold storage component comprises a support body, a cold storage material, and a beam. The support body has a wall defining a gap, the cold storage material is arranged in the gap and supported by the support body, and the beam bridges the wall.

[0014] The support body and the beam are formed of a material having a thermal conductivity better than that of the cold storage material.

[0015] According to the disclosed battery pack, since the beam bridging the support body and the support body wall has a higher thermal conductivity than the cold storage material, the heat generated by the battery cells can be effectively dissipated from the support body through the beam. As a result, a battery pack with high heat dissipation performance can be provided.

[0016] The multiple methods disclosed in this specification adopt different technical means to achieve their respective purposes. The symbols in brackets recorded in the scope of protection are exemplary representations of the correspondence with the parts of the embodiments described later, and are not intended to limit the technical scope. The purposes, features and effects disclosed in this specification will be made clearer through the subsequent detailed description and reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a diagram showing a schematic structure of an eVTOL.

[0018] Figure 2 It is a diagram showing the distribution of electric power.

[0019] Figure 3 It is a plan view schematically showing the structure of the battery pack according to the first embodiment.

[0020] Figure 4 It is along Figure 3 A cross-sectional view taken along line IV-IV.

[0021] Figure 5 It is a cross-sectional view showing the supporting body and the beam.

[0022] Figure 6 It is a top view showing the supporting body and the beam.

[0023] Figure 7 It is a graph showing the effect of the latent heat storage material.

[0024] Figure 8 It is a diagram showing the effect of the beam.

[0025] Fig. 9 It is a diagram showing the phase state of the cold storage material.

[0026] Fig.10 It is a figure which shows a modification example.

[0027] Fig.11 It is a figure which shows a modification example.

[0028] Fig.12 It is a diagram showing the arrangement of battery cells and cold storage members in a battery pack according to a second embodiment.

[0029] Fig.13 It is a perspective view showing a cold storage member in a battery pack according to a third embodiment.

[0030] Fig.14 It is a cross-sectional view showing a modified example.

[0031] Fig.15 It is a diagram showing the relationship between the pitch of beams and the phase change time in the battery pack according to the fourth embodiment.

[0032] Fig.16 It is a figure which shows a modification example.

[0033] Fig.17 It is a cross-sectional view showing a battery pack according to a fifth embodiment.

[0034] Fig.18 It is a plan view schematically showing the structure of a battery pack according to a sixth embodiment.

[0035] Fig.19 It is a cross-sectional view showing a cold storage member according to a sixth embodiment.

[0036] Fig. 20 yes Fig.19 A partial enlarged view of the cold storage component.

[0037] Fig.21 It is a cross-sectional perspective view of a cold storage member according to a sixth embodiment.

[0038] Fig. 22 It is a figure which shows the cold storage member when it is filled with the cold storage material.

[0039] Fig.23 It is a figure which shows a modification example. DETAILED DESCRIPTION

[0040] Hereinafter, a plurality of embodiments are described based on the accompanying drawings. In addition, in each embodiment, repeated descriptions are sometimes omitted by marking corresponding structural elements with the same symbols. In the case where only a part of the structure is described in each embodiment, the structure of other embodiments described in other embodiments described previously can be applied to the other parts of the structure. In addition, not only the combination of structures clearly indicated in the description of each embodiment, but also the structures of each embodiment can be partially combined with each other even if it is not clearly indicated, as long as there is no particular obstacle to the combination.

[0041] (First Embodiment)

[0042] The battery pack of this embodiment is mounted on an electric mobile body. The electric mobile body can be moved by being driven by a rotating electric motor. Examples of electric mobile bodies are vehicles, flying bodies, ships, construction machinery, agricultural machinery, and the like. Examples of electric vehicles are electric vehicles (BEV), hybrid electric vehicles (HEV), plug-in hybrid electric vehicles (PHEV), and the like. BEV is the abbreviation for Battery Electric Vehicle. HEV is the abbreviation for Hybrid Electric Vehicle. PHEV is the abbreviation for Plug-in Hybrid Electric Vehicle.

[0043] Examples of electric flying objects include electric vertical take-off and landing aircraft (eVTOL), electric take-off and landing aircraft (eSTOL), and drones. eVTOL is the abbreviation for electronic Vertical Take-Off and Landing aircraft. eSTOL is the abbreviation for electronic Short distance Take-Off and Landing aircraft. The following describes an example of an eVTOL aircraft.

[0044] <evtol>

[0045] Figure 1 As an example, the eVTOL 10 of the present embodiment includes a fuselage body 11 , fixed wings 12 , rotary wings 13 , a lift adjustment mechanism 14 , a battery 15 , an EPU 16 , a BMS 17 , and an ECU 18 .

[0046] The fuselage body 11 is the trunk of the fuselage. The fuselage body 11 is in a shape extending forward and backward. The fuselage body 11 has a passenger room for passengers and / or a cargo hold for carrying cargo.

[0047] The fixed wing 12 is a wing portion of the fuselage, and is connected to the fuselage body 11. The fixed wing 12 provides gliding lift. The gliding lift is the lift generated by the fixed wing 12. As an example, the fixed wing 12 has a main wing 121 and a tail wing 122. The main wing 121 extends to the left and right from the center of the fuselage body 11 in the front-to-back direction. The tail wing 122 extends to the left and right from the rear of the fuselage body 11. The shape of the fixed wing 12 is not particularly limited. For example, a receding wing, a delta wing, a straight wing, etc. can be used.

[0048] A plurality of rotary wings 13 are provided on the fuselage. At least a portion of the plurality of rotary wings 13 may also be provided on the fixed wing 12. At least a portion of the plurality of rotary wings 13 may also be provided on the fuselage body 11. The number of rotary wings 13 provided in the eVTOL 10 is not particularly limited. As an example, a plurality of rotary wings 13 are provided on the fuselage body 11 and the main wing 121, respectively. The eVTOL 10 has six rotary wings 13.

[0049] The rotary wing 13 is sometimes also called a rotor, a propeller, a fan blade, etc. The rotary wing 13 has a blade 131 and a shaft 132. The blade 131 is mounted on the shaft 132. The blade 131 is a blade that rotates together with the shaft 132. A plurality of blades 131 extend radially around the axis of the shaft 132. The shaft 132 is the rotation axis of the rotary wing 13, and is driven to rotate by the motor of the EPU 16.

[0050] The rotor 13 generates propulsion by rotating. During the takeoff and landing of the eVTOL 10, the propulsion mainly acts on the eVTOL 10 as a rotational lift. The rotor 13 mainly provides rotational lift during takeoff and landing. Rotational lift is the lift generated by the rotation of the rotor 13. During takeoff and landing, the rotor 13 can provide only rotational lift, or rotational lift and forward thrust. The rotor 13 provides rotational lift when the eVTOL 10 is hovering.

[0051] The propulsion force acts on the eVTOL 10 mainly as thrust during the cruising of the eVTOL 10. The rotor 13 mainly provides thrust during the cruising. During the cruising, the rotor 13 can provide only thrust or thrust and lift.

[0052] The lift regulating mechanism 14 regulates the gliding lift of the fixed wing 12. The lift regulating mechanism 14 increases or decreases the gliding lift generated by the fixed wing 12. The lift regulating mechanism 14 regulates the gliding lift by, for example, regulating at least one of the surface area, angle of attack (AOA), camber (bending of the wing), stall AOA, and wing speed of the fixed wing 12. AOA is the abbreviation of Angle Of Attack. As an example, the lift regulating mechanism 14 has a tilt mechanism 141 and a flap 142.

[0053] The tilt mechanism 141 is driven to adjust the tilt angle of the rotor 13. The tilt mechanism 141, together with the motor and inverter that drive the tilt mechanism 141, constitutes a tilt adjustment device. The tilt adjustment device including the tilt mechanism 141 is provided, for example, individually for the rotor 13. The tilt mechanism 141 adjusts the tilt angle of the rotor 13 by adjusting the relative inclination of the rotor 13 with respect to the fuselage.

[0054] During takeoff and landing, the tilt mechanism 141 controls the tilt angle so that the axis of each rotor blade 13 approaches a position parallel to the vertical direction. As a result, the propulsion force generated by the rotation of each rotor blade 13 acts mainly as a rotation lift on the eVTOL 10. Therefore, the eVTOL 10 can perform short-distance takeoff and landing and takeoff and landing in the vertical direction.

[0055] During cruising, the tilt mechanism 141 controls the tilt angle so that the axis of each rotor 13 approaches a position parallel to the horizontal direction. As a result, the propulsion force generated by the rotation of each rotor 13 acts mainly as thrust on the eVTOL 10. As a result, the eVTOL 10 can obtain gliding lift through the fixed wing 12 and move forward through the forward thrust generated by the rotation of each rotor 13. In addition, the gliding lift can be adjusted by changing the wing speed through the thrust.

[0056] In addition, although an example in which the tilting mechanism 141 is provided individually for the rotary blade 13 is shown, the present invention is not limited thereto. For example, the tilting angles of the plurality of rotary blades 13 arranged side by side may be controlled by a common tilting mechanism. Alternatively, the rotary blade 13 may be integrated with a part of the wing portion, and the part of the wing portion and the rotary blade 13 may be displaced integrally by the tilting mechanism.

[0057] The flap 142 is a movable wing and is provided on the fixed wing 12. The flap 142, together with the motor and inverter driving the flap 142, constitute a flap adjustment device. The flap 142 is sometimes referred to as a high lift device. As an example, a plurality of flaps 142 are provided at the trailing edge of the main wing 121. The plurality of flaps 142 are respectively provided with motors and inverters. In addition to being provided on the main wing 121, the flap 142 may also be provided on the tail wing 122. The flap 142 may also be provided on the leading edge of the fixed wing 12.

[0058] The flap 142 adjusts the surface area and the curvature of the fixed wing 12. For example, by controlling the flap 142 provided on the main wing 121 to a downward position, the gliding lift acting on the main wing 121 is increased. In addition, by moving the flap 142 in a direction protruding from the main wing 121, the gliding lift can be further increased.

[0059] The lift adjustment mechanism 14 is not limited to the above-mentioned tilting mechanism 141 and flap 142. As the lift adjustment mechanism 14, a tilting mechanism that adjusts the relative inclination of the fixed wing 12 with respect to the fuselage body 11 may be adopted. In this case, the angle of attack of the fixed wing 12 can be adjusted. As the lift adjustment mechanism 14, a rotary wing for thrust provided separately from the rotary wing 13 may be adopted. In this case, the wing speed can be adjusted. In addition, by providing a rotary wing for thrust, the rotary wing 13 can also be used exclusively for lift (rotation lift).

[0060] As the lift adjustment mechanism 14, a variable wing may also be used. The lift can be adjusted by changing the surface area, camber, installation angle, etc. of the fixed wing 12. As the lift adjustment mechanism 14, a high lift device different from the flap 142, such as a slat, may also be used. The slat is provided at the leading edge of the main wing 121. By moving the slat forward relative to the main wing 121, a gap can be formed between the slat and the main wing 121, thereby delaying the separation. As a result, the lift can be increased when a higher angle of attack is reached without stalling. That is, the stall AOA can be delayed.

[0061] The battery (BAT) 15 is a rechargeable secondary battery that can store direct current. The battery 15 supplies power to the EPU 16, the ECU 18, the tilt adjustment device, and the flap adjustment device. In addition, the battery 15 supplies power to auxiliary machines such as an air conditioning device that are not shown. As an example, the eVTOL 10 of this embodiment has a plurality of batteries 15. The plurality of batteries 15 can be connected in series and / or in parallel to each other, or can be independently configured without being connected to each other. The battery 15 can be provided individually with respect to the EPU 16, or can be provided redundantly with respect to the EPU 16.

[0062] EPU16 has an electric motor and an inverter, and drives the rotary wing 13 that applies propulsion force to the eVTOL10. EPU is the abbreviation of Electric Propulsion Unit. As an example, the same number of EPU16 and rotary wing 13 are provided. That is, the eVTOL10 has six EPU16. EPU16 and rotary wing 13 are connected one-to-one. Alternatively, it can also be a structure in which one EPU16 is connected to two or more rotary wings 13 via a gear box.

[0063] The BMS 17 monitors the state of the battery 15. BMS is an abbreviation for Battery Management System. For example, one BMS 17 is provided for one battery 15. The BMS 16 monitors the states of the multiple batteries 15, and can predict the abnormality of each battery 15, and can also detect the abnormality of each battery 15.

[0064] ECU18 controls the flight of eVTOL10. ECU is the abbreviation of Electronic Control Unit. ECU18 performs control for making eVTOL10 fly in a flight state corresponding to the operation of the driver as an operator, the remote operation of the operator, or the control of the control system. ECU18 performs flight control based on the detection results of BMS17 or various sensors. ECU18 controls the drive of the motor of EPU16, the motor of the tilt adjustment device, and the motor of the flap adjustment device, for example. ECU18 can also perform control of auxiliary machines.

[0065] <Electric Power Distribution>

[0066] Figure 2 The electric power distribution of eVTOL 10 from takeoff to landing is shown. In addition, the electric power distribution of electric flying objects other than eVTOL is the same as that of eVTOL. Period K1 is called takeoff period, takeoff time, departure period, departure time, etc. Period K2 is called cruising period, cruising time, etc. Period K3 is called landing period, landing time, arrival period, arrival time, etc. For convenience, Figure 2 In the above, the required power, that is, the output power is set constant in substantially the entire region of each of the periods K1 and K3.

[0067] During period K1, the eVTOL 10 ascends from the take-off point to the cruise start point. During period K2, the eVTOL cruises at a predetermined altitude. During period K3, the eVTOL 10 descends from the end point of period K2 to the landing point. The movement of the eVTOL 10 mainly includes a horizontal component during period K2, and mainly includes a vertical component during periods K1 and K3. During periods K1 and K3 of movement in the vertical direction, the drive of the rotor 13 of the eVTOL 10 requires continuous high output power for a predetermined time.

[0068] Due to this high output, a large load is applied to the battery 15 and the EPU 16 which are driving devices for driving the rotor 13. For example, the battery 15 generates heat and its temperature rises temporarily.

[0069] <Battery Pack>

[0070] Figure 3 The schematic structure of the battery pack is shown in FIG. Figure 3 In the figure, a part of the housing is omitted in order to show the battery cells etc. housed in the housing. Figure 3 In the figure, the battery cell 30 is partially omitted. Figure 4 The arrangement of the battery cells and the cold storage member is shown. Figure 4 It is along Figure 3 A cross-sectional view of the IV-IV line. Figure 4 In the figure, the structure of the battery cell is simplified. Figure 5 Shown from Figure 4 The structure of the cold storage material after the cold storage component is removed is shown. That is, the structure of the support body and the beam is shown. Figure 6 A top view showing the structure of the supports and beams.

[0071] Hereinafter, the height direction of each battery cell is represented as the Z direction, the length direction of each battery cell is represented as the Y direction, and the width direction of each battery cell is represented as the X direction. The X direction, the Y direction, and the Z direction are orthogonal to each other.

[0072] like Figure 3 and Figure 4 As shown, the battery pack 20 includes a plurality of battery cells 30, a cold storage member 40, and a housing 50. In addition, the battery pack 20 also includes a bus bar, a connector, a fixing member, etc., which are not shown.

[0073] The battery cell 30 is a secondary battery that generates a starting voltage through a chemical reaction. The battery cell 30 is, for example, a lithium-ion secondary battery, a nickel-hydrogen secondary battery, an organic free radical battery, etc. The battery cell 30 may be a secondary battery with a liquid electrolyte or a so-called all-solid battery with a solid electrolyte.

[0074] The multiple battery cells 30 have a common structure. The number and configuration of the multiple battery cells 30 are not particularly limited. The multiple battery cells 30 can be connected in series, or can be connected in parallel and in series. As an example, the battery cells 30 of the present embodiment are connected in series. The multiple battery cells 30 are arranged in the X direction. The multiple battery cells 30 are stacked (stacked) in the X direction via the cold storage component 40. The battery pack 20 can have a stack of multiple battery cells 30. The electrical connection structure of multiple battery cells 30 is sometimes called a battery pack. The multiple battery cells 30, i.e., the battery pack, included in a battery pack 20 is equivalent to one of the above-mentioned batteries 15.

[0075] The battery cell 30 has a power generation element and a battery casing that accommodates the power generation element. The battery casing provides an outer contour of the battery cell 30. The battery casing is formed, for example, using a metal material. The shape of the battery cell 30, i.e., the battery casing, is not particularly limited. For example, a cylindrical shape, a square shape, etc. can be adopted. As an example, the battery cell 30 of this embodiment is a square shape, specifically a flat shape that is thin in the X direction.

[0076] The battery cell 30 has an upper surface 30a, a bottom surface 30b, and four side surfaces 30c. The bottom surface 30b is a surface opposite to the upper surface 30a in the Z direction. The side surface 30c is a surface connecting the upper surface 30a and the bottom surface 30b. Two of the side surfaces 30c are in an opposite positional relationship to each other in the X direction. The other two of the side surfaces 30c are in an opposite positional relationship to each other in the Y direction.

[0077] A plurality of battery cells 30 are arranged in an X direction. Each battery cell 30 has electrode terminals 31P and 31N protruding from an upper surface 30a. The electrode terminal 31P is electrically connected to the positive electrode of the battery cell 30. The electrode terminal 31P is sometimes referred to as a positive electrode terminal, a P terminal, etc. The electrode terminal 31N is electrically connected to the negative electrode of the battery cell 30. The electrode terminal 31N is sometimes referred to as a negative electrode terminal, an N terminal, etc. The electrode terminal is sometimes referred to as a collector tab.

[0078] The plurality of battery cells 30 are arranged so that the positions of the electrode terminals 31P and the electrode terminals 31N are alternated in the X direction. In addition, the plurality of battery cells 30 are arranged so that the positions of the upper surfaces 30a in the Z direction are substantially the same. The relative positions of the plurality of battery cells 30 are fixed by a fixing member (not shown). The fixing member may be, for example, a housing or a restraining member such as a belt-shaped binding band.

[0079] In the above arrangement, the electrode terminals 31P and 31N of the adjacent battery cells 30 are electrically connected by a bus bar (not shown). That is, the plurality of battery cells 30 are connected in series by the bus bar.

[0080] The cold storage member 40 includes a support body 41, a cold storage material 42, and a beam 43. When the cold storage member 40 is relatively thinner than the battery cell 30, the cold storage member 40 may be referred to as a cold storage sheet.

[0081] The support body 41 supports the cold storage material 42. The support body 41 has a wall 411 and a gap 412 defined by the wall 411. The support body 41 holds the cold storage material 42 in its storage space. The support body 41 is formed using a material having a higher thermal conductivity than the cold storage material 42. The support body 41 can be formed using, for example, metal, ceramic, resin with a filler added, or the like.

[0082] As an example, the support body 41 of this embodiment is formed of a metal, specifically an aluminum-based material. The support body 41 is in a box shape that is thinner in the X direction. The support body 41 has opposing walls 411a, 411b and a side wall 411c. The opposing walls 411a, 411b are opposite to each other in the X direction. The side wall 411c connects the ends of the opposing walls 411a, 411b and closes the gap 412.

[0083] The cold storage material 42 is a component that performs a cold storage effect. The cold storage material 42 cools the battery cell 30 by absorbing the heat generated by the battery cell 30. The cold storage material 42 is, for example, a latent heat cold storage material. Water or cooling water to which LLC is added may be used instead of the latent heat cold storage material. LLC is the abbreviation of Long Life Coolant. In addition, the cold storage material is sometimes also referred to as a heat storage material.

[0084] As an example, the cold storage material 42 of the present embodiment is a latent heat storage material. Latent heat storage material is sometimes referred to as PCM. PCM is the abbreviation of Phase change material. Latent heat storage material undergoes a phase change between solid and liquid. Latent heat storage material utilizes the latent heat of a substance. The latent heat storage material maintains the temperature of the battery cell 30 at a specified temperature or a specified temperature range. As a latent heat storage material, for example, a non-hydrate carbon compound, specifically a paraffin-based carbon compound, can be used. A hydrate system can also be used instead. Examples of hydrate systems are hydrates such as sodium acetate, sodium sulfate, and sodium nitrate.

[0085] As an example, the cold storage material 42 of the present embodiment is a non-hydrate carbon compound, that is, a paraffin-based cold storage material. In addition, the phase transition temperature between the solid phase and the liquid phase of the cold storage material 42 is set to be within the range of 30°C to 60°C. The density of the solid of the cold storage material 42 (for example, paraffin-based) is higher than the density of the liquid. Therefore, when changing from the solid phase to the liquid phase, the volume expands by about 10%. Therefore, the filling rate relative to the void 412 in the solid state can be adjusted so that the filling rate in the liquid state is less than 100%, preferably a value close to 100%.

[0086] The beam 43 bridges the wall 411 of the support body 41. The beam 43 is in contact with the cold storage material 42. The beam 43 is sometimes called a bridging member. The beam 43 is formed of a material having a thermal conductivity higher than that of the cold storage material 42, similarly to the support body 41. The beam 43 can be formed of, for example, metal, ceramic, or resin with a filler added. The beam 43 can be formed of the same material as the support body 41, or a different material. The beam 43 can be provided integrally with the support body 41 by continuous connection, or can be provided integrally with the support body 41 by bonding. The beam 43 can bridge the walls 411 that are different from each other.

[0087] As an example, Figure 4 and Figure 5 As shown, the beam 43 of this embodiment bridges the pair of opposite walls 411a and 411b. Figure 6 As shown, a plurality of beams 43 extending in the Y direction are integrally provided with the support body 41. At least a portion of each of the plurality of beams 43 is in contact with the cold storage material 42. The plurality of beams 43 are provided at a predetermined pitch P1 in the Z direction. The plurality of beams 43 divide the gap 412, i.e., the cold storage material 42 disposed in the gap 412, into a plurality of parts. The beams 43 are sometimes referred to as separators, separation walls, etc. The beams 43 are continuously connected to the support body 41. The beams 43 and the support body 41 are integrally formed by extrusion tube processing using aluminum as a material. Extrusion tube processing is sometimes referred to as extrusion pipe processing.

[0088] like Figure 3 As shown in FIG. 1 , the cold storage members 40 of the above structure are arranged alternately with the battery cells 30 in the X direction which is the stacking direction. Figure 4 As shown, the opposite wall 411a of the support body 41 is in direct contact with one side surface 30c of the battery cell 30. The opposite wall 411b of the support body 41 is in direct contact with the other side surface 30c of the battery cell 30. The cold storage component 40 is clamped by the battery cell 30 in the X direction. The opposite walls 411a, 411b may also be in indirect contact with the battery cell 30. For example, it may be in contact with the battery cell 30 via a heat conductive component such as TIM that is not shown. TIM is the abbreviation of Thermal Interface Material. The cold storage component 40 may be, for example, adhesively fixed to the battery cell 30.

[0089] In addition, Figure 3 In the figure, an example is shown in which the cold storage component 40 is arranged only on one side, specifically, only on the inner side in the stacking direction, of the battery cells 30 located at both ends in the stacking direction. Alternatively, a structure in which the cold storage component 40 is also arranged on the outer side in the stacking direction may be adopted. In this case, the cold storage component 40 located at both ends in the stacking direction contacts the side surface 30c of the battery cell 30 with only one of the opposing walls 411a and 411b.

[0090] The shell 50 accommodates the battery cell 30. The shell 50 can be formed of a metal material such as aluminum, or a resin material. The cold storage component 40 can be accommodated in the shell 50, or at least a part of it can be arranged outside the shell 50. As an example, the shell 50 of this embodiment is formed (die-cast) using an aluminum material. The shell 50 accommodates the battery cell 30 and the cold storage component 40. The heat generated by the battery cell 30 is dissipated to the bottom wall side of the shell 50 through the cold storage component 40. The bottom wall is a wall portion on the bottom surface 30b side of the battery cell 30 in the shell 50.

[0091] <Summary of First Embodiment>

[0092] According to the present embodiment, the battery pack 20 includes a cold storage component 40. The cold storage component 40 includes a support body 41, a cold storage material 42, and a beam 43. The support body 41 includes a wall 411 defining a gap 412, the cold storage material 42 is arranged in the gap 412 and supported by the support body 41, and the beam 43 bridges the wall 411. The support body 41 and the beam 43 are formed using a material having a higher thermal conductivity than the cold storage material 42. The cold storage material 42 is in contact not only with the support body 41 but also with the beam 43. The heat of the battery cell 30 is transferred not only from the support body 41 but also from the beam 43 to the cold storage material 42.

[0093] Therefore, even if the thermal conductivity of the cold storage material 42 is low, the cold storage material 42 can absorb heat efficiently. Therefore, the heat generated by the battery cells 30 can be effectively dissipated. As a result, the battery pack 20 with high heat dissipation performance can be provided compared with a structure without the beam 43.

[0094] The cold storage component is lighter than a cooler in a circulation system that circulates a refrigerant and performs cooling. As a result, cooling performance can be ensured and weight can be reduced, especially in an electric flying vehicle such as eVTOL10. As a result, for example, the cruising distance can be extended.

[0095] As an example, in this embodiment, the beam 43 bridges the opposing walls 411a and 411b of the support body 41. Furthermore, at least one of the opposing walls 411a and 411b is in direct or indirect contact with the battery cell. Figure 4 The heat transfer is shown by the dashed arrows. Figure 4 As shown, heat is transferred not only from the opposing walls 411a and 411b to the cold storage material 42, but also from the opposing walls 411a and 411b to the cold storage material 42 through the beam 43. In addition, in the case of a structure in which contact is made through one of the opposing walls 411a and 411b, heat is transferred to the other of the opposing walls 411a and 411b through the beam 43. Since heat is transferred to the entire area of ​​the cold storage material 42, heat dissipation can be further improved.

[0096] As an example, in the present embodiment, the beam 43 is a plurality of columnar bodies extending in one direction (Y direction). The beam 43 of such a structure can be integrally formed with the support body 41. It is possible to ensure cooling performance and reduce the weight of the cold storage component 40. The cold storage component 40 has a plurality of beams 43. The gap 412 is divided into a plurality of regions by the plurality of beams 43. The cold storage material 42 is also divided into a plurality of regions by the plurality of beams 43. Therefore, heat is easily transferred to all regions of the cold storage material 42.

[0097] As an example, in the present embodiment, at least a portion of the cold storage component 40 is arranged between adjacent battery cells 30 and clamped by the battery cells 30. The cold storage component 40 is clamped by the battery cells 30 from both sides in the X direction which is the stacking direction. In this structure, the heat of the battery cell 30 is transferred from the side surface 30c to the cold storage component 40. The side surface cooling structure can increase the contact area. In addition, the thermal resistance from the battery cell 30 to the cold storage material 42 can be reduced. Therefore, the heat dissipation can be further improved. Moreover, by having the beam 43, the expansion of the battery cell 30 during charging can be suppressed. Thus, the generation of uneven electrochemical reactions can be suppressed. In addition, the shape of the cold storage component 40 is maintained by the beam 43, so the fixing structure of the fixing component to the battery cell 30 can be maintained.

[0098] Figure 7 4 is a simulation result showing the relationship between the presence or absence of the beam 43 and the amount of heat dissipated from the battery cell 30. In this simulation, the battery cell 30 and the cold storage member 40 are as follows. Figure 4 As shown in the configuration. In addition, the cold storage material 42 is a latent heat storage material of the paraffin system, with a melting point set to a specified temperature between 40°C and 45°C, a thermal conductivity set to 0.1W to 1W / (m·K), and a latent heat set to a specified value between 100 and 200KJ / L. In addition, the support body 41 and the beam 43 are made of aluminum with a thickness of 0.2mm, and the spacing between the beams 43 is set to 2mm. Figure 7 In FIG. 1 , a structure including the beam 43 is indicated by a solid line, and a structure without the beam 43 is indicated by a dotted line. In addition, the melting start time of the regenerator material 42 is indicated by a dashed line. Figure 8 1 shows the phase state of the regenerator material 42 at the time when 180 seconds have passed in the above simulation. Figure 8 In the figure, the solid phase (solid) is represented by dense dot hatching, and the liquid phase (liquid) is represented by sparse dot hatching.

[0099] like Figure 7 As shown in FIG. 1 , due to the effect of latent heat, the amount of heat dissipated increases after melting begins. In addition, it is known that the amount of heat dissipated from the battery cell 30, that is, the amount of heat transferred to the cold storage member 40, can be increased by providing the beam 43. Figure 8 It is known that the dissolution residue from the solid phase to the liquid phase can be reduced by providing the beam 43. That is, it is known that heat is transferred to substantially the entire region of the cold storage material 42.

[0100] As the cold storage material 42, a refrigerant such as water may be used as described above. In the present embodiment, a latent heat cold storage material is used as the cold storage material 42. The latent heat cold storage material has a high specific heat. Therefore, it is possible to ensure the heat capacity (thermal mass) and further reduce the amount of cold storage material 42 required to cool the battery 15. Therefore, it is possible to further extend the cruising range of, for example, the eVTOL 10.

[0101] Fig. 9 Indicates the simulation results. The horizontal axis represents the temperature T0℃ before discharge, and the vertical axis represents the required load m. The required load m is zero (0) at the lower end, and the value increases as it goes up. In this simulation, water is compared with a latent heat storage material. The specific heat Cpcm of the latent heat storage material is set to 2kJ / (kg·K), and the latent heat L is set to a specified value between 100 and 200kJ / L. In addition, the heat capacity Ccell of the battery cell 30 is set to approximately 200J / K, the calorific value Q is set to 12kJ, and the upper limit temperature Tmax is set to 55K. Fig. 9 The solid line shown represents the results for the latent heat storage material (PCM), and the dashed line represents the results for water.

[0102] The average specific heat Cave can be calculated by Formula 1. The required loading amount m can be calculated by Formula 2. In addition, ΔT is the difference between the upper limit temperature Tmax and the temperature T0.

[0103] Cave=(Cpcm·ΔT+L) / ΔT…(Formula 1)

[0104] (Ccell+m·Cave)·ΔT=Q...(Formula 2)

[0105] like Fig. 9 As shown, it can be seen that when the latent heat cold storage material is used, the required cooling performance can be ensured and the amount of the cold storage material 42 loaded can be reduced.

[0106] As an example, in this embodiment, the phase transition temperature between the solid phase and the liquid phase of the latent heat storage material is set between 30° C. and 60° C. This allows the temperature of the battery cell 30 to be maintained at a temperature lower than the upper limit temperature of the battery cell 30 assumed in the eVTOL 10 .

[0107] As an example, the latent heat storage material of this embodiment is a non-hydrate carbon compound, that is, a paraffin-based material. The overcooling of the latent heat storage material of the paraffin-based material is slight. In addition, since it does not corrode aluminum, it is suitable for the combination of the support body 41 and the beam 43 made of aluminum.

[0108] The cold storage material 42 is supported by the support body 41. The cold storage material 42 is held on the support body 41 in a state of filling the gap 412 of the support body 41. Therefore, it is easy to separate the cold storage component 40 containing the cold storage material 42 from the battery cell 30. The cold storage component 40 is arranged in a manner that can be loaded and unloaded relative to the battery cell 30. By being configured to be loadable and unloadable, for example, the cold storage component 40 can be removed after the flight of the eVTOL 10, and the cold storage component 40 can be cooled and returned to the solid phase. For example, the cold storage component 40 can be removed after the flight and replaced with another cold storage component 40 that has undergone a phase transition to the solid phase. By replacing, the preparation time for the next flight can be reduced.

[0109] <Modification>

[0110] Although an example is shown in which the beam 43 bridges the wall (opposing wall 411a, 411b) in contact with the battery cell 30, the present invention is not limited thereto. For example, the beam 43 may bridge between the side walls 411c. In such a structure, heat is transferred from the support body 41 to the cold storage material 42 through the beam 43. Therefore, compared with a structure without the beam 43, heat dissipation can be improved.

[0111] As a latent heat storage material, an example of a paraffin system is shown, but it is not limited to this. A latent heat storage material that is water-soluble and adjusted to a pH between 6 and 8 can also be used. For example, the above-mentioned hydrate system meets the requirements. By adjusting the pH to the neutral region, the corrosion of aluminum can be suppressed. In addition, in the hydrate system, the supercooling of the latent heat storage material is also slight. In addition, the adjustment of the phase transition temperature is relatively easy.

[0112] The cold storage member 40 protrudes from the wall 411, but the beam 43 may further include a protruding portion that does not bridge the wall 411. The protruding portion is formed of the same material as the beam 43. Therefore, the heat dissipation can be improved.

[0113] like Fig.10 As shown, an extension portion 411d may also be provided on the support body 41. The extension portion 411d extends from the side wall 411c along the bottom surface 30b. The extension portion 411d extends in a direction orthogonal to the Z direction. The extension portion 411d is preferably in direct or indirect contact with the bottom surface 30b of the battery cell 30. Heat is transferred to the extension portion 411d through the battery cell 30, other parts of the support body 41, and at least one of the cold storage material 42. By having the extension portion 411d, the heat absorbed by the cold storage material 42 is easily released to the bottom surface 30b side. Therefore, in a structure in which a heat exchange element such as a heat sink fin is arranged on the bottom surface 30b side of the battery cell 30, the heat dissipation can be improved.

[0114] like Fig.11 As shown, the cold storage member 40 may also be configured in a meandering shape. Fig.11 In the embodiment, the battery cells 30 are cylindrical. The battery cells 30 are arranged in a staggered shape when viewed from the Z direction. The cold storage component 40 is sandwiched between adjacent battery cells 30 and has a meandering shape. The beam bridges the opposite walls 411a and 411b of the support body 41. The first column of battery cells 30 in the X direction contacts the opposite wall 411a, and the second column of battery cells 30 contacts the opposite wall 411b.

[0115] (Second Embodiment)

[0116] This embodiment is a modification of the previous embodiment as a basic form, and the description of the previous embodiment can be cited. In the previous embodiment, the cold storage member is in contact with the side surface of the battery cell. Alternatively, the cold storage member may be in contact with the bottom surface of the battery cell.

[0117] Fig.12 The arrangement of the battery cells 30 and the cooling member 40 in the battery pack 20 of the present embodiment is shown. Fig.12 and Figure 4 Corresponding. The cold storage component 40 is arranged on the bottom surface 30b side of the battery cell 30. The cold storage component 40 has a support body 41 and a beam 43 in the same manner as the previous embodiment. The support body 41 has relative walls 411a and 411b, and the beam 43 bridges the relative walls 411a and 411b. Moreover, the relative wall 411a of the support body 41 is in direct or indirect contact with the bottom surface 30b. The cold storage component 40 is configured to enclose all the battery cells 30 when viewed from above in the Z direction. The cold storage component 40 is in contact with the bottom surface 30b of each battery cell 30. The other structures are the same as those described in the previous embodiment.

[0118] <Summary of Second Embodiment>

[0119] In the present embodiment, at least a portion of the cold storage component 40 is in contact with the bottom surface 30b of the battery cell 30. The heat of the battery cell 30 is transferred not only from the support body 41 but also from the beam 43 to the cold storage material 42. Therefore, even if the thermal conductivity of the cold storage material 42 is low, the cold storage material 42 can absorb heat efficiently. Therefore, the heat generated by the battery cell 30 can be effectively dissipated. Since the weight of the battery cell 30 acts on the cold storage component 40, thermal contact is easily made.

[0120] In addition, since the cold storage member 40 is disposed on the bottom surface 30b side of the battery cell 30, the cold storage member 40 including the cold storage material 42 can be easily separated from the battery cell 30 compared to a structure in which the cold storage member 40 contacts the side surface 30c of the battery cell 30. In other words, it is easy to configure a structure in which the cold storage member 40 can be attached to and detached from the battery cell 30.

[0121] Furthermore, by providing the beams 43, deformation of the cold storage member 40 can be suppressed even when the weight of the battery cell 30 acts. The shape of the cold storage member 40 can be maintained by the beams 43, so the fixing structure of the fixing member to the battery cell 30 can be maintained.

[0122] <Modification>

[0123] Although an example is shown in which a common (single) cold storage component 40 is configured for a plurality of battery cells 30, the present invention is not limited thereto. The battery pack 20 may also include a plurality of cold storage components 40. For example, in a structure in which a battery stack formed by stacking a plurality of battery cells 30 includes a plurality of cold storage components 40, the cold storage components 40 may be provided for each battery stack.

[0124] The structures described in the previous embodiment, except for the structure configured so that the cold storage component 40 contacts the side surface 30c, can be combined with the structure described in this embodiment. For example, in the structure in contact with the bottom surface 30b, the cold storage material 42 can be used as a latent heat cold storage material. The cold storage component 40 having a beam 43 bridging the side walls 411c can be used. The support body 41 can have an extension portion 411d extending in a direction orthogonal to the Z direction.

[0125] (Third Embodiment)

[0126] This embodiment is a modified example based on the previous embodiment, and the description of the previous embodiment can be cited. In the previous embodiment, the beam 43 is formed integrally with the support body 41 by extrusion tube processing. However, the structure of the support body 41 and the beam 43 is not limited to this example. In this embodiment, a structure that can be further lightweight is shown.

[0127] Fig.13 1 is a plan view showing the cold storage member 40 in the battery pack 20 according to the present embodiment. Fig.13 and Figure 6 Corresponding. Fig.13 In FIG. 4 , the opposite wall 411 b on the front side is indicated by a single-dot chain line. That is, in order to indicate the beam structure, the opposite wall 411 b is shown through.

[0128] Fig.13 The cold storage component 40 shown also has a support body 41, a cold storage material 42 and a beam 43. The support body 41 has a pair of opposite walls 411a and 411b as a wall 411. The support body 41 does not have a side wall 411c. The beam 43 forms a honeycomb structure. The beam 43 bridges the opposite walls 411a and 411b in the X direction. The beam 43 is fixed to the flat opposite walls 411a and 411b by, for example, bonding, adhesion, etc. The gap 412 of the support body 41 is divided into a plurality of regions in the shape of a roughly regular hexagonal prism by the opposite walls 411a and 411b and the beam 43. Moreover, the cold storage material 42 is filled in each region. The other structures are the same as those described in the previous embodiment.

[0129] <Summary of the Third Embodiment>

[0130] In this embodiment, the beam 43 forms a honeycomb structure. The honeycomb structure can ensure the strength to withstand the expansion of the battery cell 30, the weight of the battery cell 30, and the pressure caused by the fixing components, and reduce the weight of the beam 43. Therefore, the heat dissipation can be improved, and the cold storage component 40 can be made lighter, thereby making the battery pack 20 lighter.

[0131] <Modification>

[0132] like Fig.14 As shown, a cold storage component 40 having a fin-shaped beam 43 may also be used. The fin shape is sometimes called a corrugated plate shape. The cold storage component 40 forms an inner fin structure in which a fin-shaped beam 43 is arranged inside the support body 41. Such an inner fin structure can also ensure the strength of the pressure caused by the expansion, dead weight, and fixing components of the battery cell 30, and reduce the weight of the beam 43. Therefore, the heat dissipation can be improved, and the cold storage component 40 can be made lighter, thereby making the battery pack 20 lighter.

[0133] The structure described in this embodiment can be combined with any of the structures described in the previous embodiment. For example, in the structure in contact with the side surface 30c, the cold storage component 40 of the above-mentioned honeycomb structure or inner fin structure can also be used. In the structure in contact with the bottom surface 30b, the cold storage component 40 of the honeycomb structure or inner fin structure can also be used. In the cold storage component 40 of the honeycomb structure or inner fin structure, the cold storage material 42 can also be used as a latent heat cold storage material.

[0134] (Fourth Embodiment)

[0135] This embodiment is a modification of the previous embodiment as a basic form, and the description of the previous embodiment can be cited. In the previous embodiment, the pitch P1 (interval) of the beams 43 is not particularly mentioned. In this embodiment, a preferred pitch P1 of the beams 43 is described.

[0136] Fig.15 The pitch P1 of the beams 43 in the battery pack 20 of the present embodiment (see Figure 5 ) versus phase transition time. Fig.15 4 shows the simulation results using the Stefan solution. In this simulation, the thickness TH1 of the cold storage material 42 (see Figure 5 ) is set to 15mm. The phase change time is the time taken for the change from solid phase to liquid phase to be completed, that is, the time taken for melting to be completed. Fig.15 The lower end is zero (0), and the value increases as it moves upward.

[0137] If the pitch P1 is less than 1 mm, it is difficult to form the beam 43 with high precision. In addition, if the pitch P1 is close to the thickness TH1, the change in the phase change time becomes small, and even if the pitch P1 is increased, the phase change time does not change and shows a substantially constant value. The effect of the pitch P1 on the phase change time is significant up to 10 mm. In this embodiment, based on this result, the pitch P1 of the beam 43 is set within the range of 1 mm to 10 mm. One dotted line is 1 mm as the lower limit value, and the other dotted line is 10 mm as the upper limit value.

[0138] <Summary of Fourth Embodiment>

[0139] As described above, in this embodiment, the pitch P1 of the beams 43, that is, the interval between adjacent beams 43, is set to be between 1 mm and 10 mm. By setting this range, the regenerator material 42 can be changed from a solid phase to a liquid phase in a short time.

[0140] In addition, if the pitch P1 is shorter than the thickness TH1, the phase change time can be shortened. That is, by making the pitch P1 thinner, heat can easily spread throughout the entire cold storage material 42, and dissolution residue can be suppressed. Therefore, instead of the above range, the pitch P1 can be set within a range of 1 mm or more and less than the thickness TH1.

[0141] <Modification>

[0142] Although the example in which the pitch P1 of the beams 43 is constant is shown, the present invention is not limited thereto. The pitch P1 may also be different depending on the position. Fig.16 As shown, the pitch P1 of the beams 43 can be made narrower as it approaches the electrode terminals 31P and 31N. The current of the battery cell 30 is concentrated near the electrode terminals 31P and 31N. That is, it is easy to become high temperature. According to the above configuration, the heat of the electrode terminals 31P and 31N can be effectively released, and the temperature can be suppressed. Preferably, the pitch P1 of the beams is set between 1 mm and 10 mm, and the closer to the electrode terminals 31P and 31N, the narrower it can be.

[0143] (Fifth Embodiment)

[0144] This embodiment is a modification of the previous embodiment as a basic form, and the description of the previous embodiment can be cited. In this embodiment, a structure that is easier to attach and detach is shown.

[0145] Fig.17 2 is a cross-sectional view showing a battery pack 20 according to this embodiment. Fig.17 In FIG. 2 , the fixing structure of the battery pack 20 is shown. Fig.17 In the figure, the battery cell 30 is partially omitted. The battery pack 20 is fixed to the bracket 100. The battery pack 20 is fixed to the body via the bracket 100.

[0146] The bracket 100 has an opening 101. The cold storage component 40 is fixed to the bottom wall 50a of the shell 50 via the opening 101. The cold storage component 40 is fixed to the shell 50 by, for example, bonding, bolting, etc. The cold storage component 40 is configured so that the relative wall 411a is in contact with the bottom wall 50a. The cold storage component 400 is configured to enclose a plurality of battery cells 30 when viewed from above in the Z direction. The TIM 60 is configured at a portion of the inner surface of the bottom wall 50a that overlaps with the cold storage component 40 when viewed from above. A plurality of battery cells 30 are arranged on the bottom wall 50a via the TIM 60. The heat of the battery cells 30 is transferred to the cold storage component 40 via the TIM 60 and the metal shell 50 (bottom wall 50a).

[0147] <Summary of Fifth Embodiment>

[0148] In the present embodiment, the cold storage component 40 is provided to be detachable from the housing 50. That is, the cold storage component 40 is provided to be detachable from other components constituting the battery pack 20. The cold storage component 40 is provided to be detachable from the battery cell 30. For example, by releasing the bolt fastening, the cold storage component 40 can be removed from other components of the battery pack 20. Therefore, the heat dissipation can be improved, and the detachability can be improved.

[0149] Since loading and unloading is easy, for example, the cold storage component 40 can be removed after the flight of the eVTOL 10, and the cold storage component 40 can be cooled and returned to the solid phase. For example, the cold storage component 40 can be removed after the flight and replaced with another cold storage component 40 that has already phase-changed (already cooled) to the solid phase. In the case of replacement, the loss of cooling time can be eliminated.

[0150] (Sixth Embodiment)

[0151] This embodiment is a modification example based on the previous embodiment, and the description of the previous embodiment can be cited.

[0152] like Fig.18 In this way, the plurality of battery cells 30 and the plurality of cold storage materials 42 are pressed and fixed by the pressing member 51 as a fixing member. The pressing member 51 is a belt-shaped binding band. In this embodiment, two pressing members 51 press and fix the plurality of battery cells 30 and the plurality of cold storage members 40 in the stacking direction (X direction). At this time, as described in the previous embodiment, the beam 43 extends in the stacking direction to bridge the opposite walls 411a and 411b.

[0153] Fig.19 It is a cross-sectional view of the cold storage member 40 before the cold storage material 42 is filled in the present embodiment. Fig. 20 Yes Fig.19 The support body 41 is a cylindrical passage portion 80 extending in the Y direction. The passage portion 80 includes a passage for filling the gap 412 with gas or liquid from the outside to the inside.

[0154] like Fig. 20 As shown, the passage portion 80 has a hollow extending in the Y direction, and the hollow is equivalent to a passage for filling gas and liquid. The upper end and the lower end of the passage portion 80 in the Y direction are open respectively, and the lower end is open toward the gap 412. The passage portion 80 is arranged at the end of the support body 41. Through the hollow of the passage portion 80, the cold storage material 42, inert gas, etc. can be filled from the outside to the inside of the cold storage component 40. The passage portion 80 can be provided with only one or more passage portions on the support body 41. As an example, the passage portion 80 is formed using metal. After being filled with the cold storage material 42 and the inert gas, the upper end of the passage portion 80 in the Y direction can be closed by riveting.

[0155] The support body 41 includes a gas injection passage 80a, a filling passage 80b, and a cover 70. The gas injection passage 80a is a passage through which an inert gas can be injected into the gap 412. The hollow space extending in the Y direction of the passage portion 80 forms the gas injection passage 80a. The inert gas is filled in the gap 412 of the cold storage component 40 together with the cold storage material 42. The cold storage component 40 may be provided with only one gas injection passage 80a or with a plurality of gas injection passages. The gas injection passage 80a may be a gas discharge passage 80c which is a passage for discharging gas.

[0156] The cover 70 seals the gap 412 so that the inert gas and the cold storage material 42 filled in the gap 412 do not leak out of the cold storage member 40. The cover 70 is provided on the upper part and the lower part of the support body 41. The cover 70 is made of a resin material.

[0157] The filling passage 80b is a passage that can fill the cold storage material 42 into the gap 412. The hollow space extending in the Y direction of the passage portion 80 forms the filling passage 80b. The filling passage 80b may be provided with only one or more filling passages in the support body 41. The gas injection passage 80a and the filling passage 80b are common passages. In the present embodiment, the beam 43 is a flat plate extending along the XY plane. The plate surface of the beam 43 extends in the direction (Y direction) in which the filling passage 80b opens relative to the gap 412.

[0158] The gap 412 includes a plurality of beam paths 412a divided by the beam 43 and a connecting path 412b that connects the plurality of beam paths 412a to each other. The beam paths 412a extend substantially parallel to the direction (Y direction) in which the plate surface of the beam 43 extends. The cold storage material 42 is filled into the beam paths 412a through the filling path 80b.

[0159] The communication path 412b is, for example, Fig.21 The beam 43 is formed by cutting in that way. The connecting path 412b only needs to be a structure that connects multiple beam paths 412a to each other, and can also be formed by processing other than cutting. A plurality of connecting paths 412b are provided. The connecting paths 412b are arranged at different multiple positions in the direction (Y direction) of filling the cold storage material 42 into the beam path 412a. In other words, the connecting paths 412b are arranged in parallel along the direction (Y direction) of the filling path 80b opening relative to the gap 412. The direction of filling the cold storage material 42 can also be understood as the extension direction of the filling path 80b and the direction of the filling path 80b opening relative to the gap 412.

[0160] In this embodiment, if Fig.19 As shown, the communication paths 412 b are provided at the upper end and the lower end of the support body 41 in the direction in which the cold storage material 42 is filled. Fig. 22 4 is a diagram showing the cold storage component 40 after the cold storage material 42 is filled into the gap 412. Fig. 22 As shown, the communication passage 412b at the lower end of the support body 41 allows the portions filled with the regenerator material 42 to communicate with each other. The communication passage 412b at the upper end of the support body 41 faces the opening of the filling passage 80b and allows the portions filled with the inert gas to communicate with each other.

[0161] One of the communication paths 412b is provided at the lower end of the support body 41 in the Y direction, but may be provided at other locations. The communication path 412b may be provided between the center portion and the lower portion in the Y direction of the support body 41. It may also be provided at a position where the portions filled with the cold storage material 42 are connected to each other after the cold storage material 42 is filled.

[0162] One of the communication paths 412b is provided at the upper end of the support body 41 in the Y direction, but may be provided at other locations. It may also be provided between the upper part and the central part in the Y direction of the support body 41. The portion of the cold storage component 40 that is not filled with the cold storage material 42 is filled with an inert gas. In addition, a gas such as air may be filled instead of the inert gas.

[0163] Here, a method of replacing the air remaining in the gap 412 with an inert gas after the cold storage material 42 is filled into the cold storage component 40 via the passage portion 80 (filling passage 80b) is described. The inert gas cylinder is connected to the passage portion 80, that is, the gas injection passage 80a, the gas discharge passage 80c, and the filling passage 80b through a three-way valve through piping. The three-way valve has valves in three directions. The valve connected to the inert gas cylinder is used as the first valve, the valve connected to the passage portion 80 is used as the second valve, and the valve connected to the check valve is used as the third valve.

[0164] When replacing the gas, first, the first valve and the second valve are opened to introduce the inert gas into the gap 412 via the passage portion 80 (gas injection passage 80a). Thereafter, the first valve is closed and the second valve and the third valve are opened to extract the gas (residual air and inert gas) that has entered the gap 412 via the passage portion 80 (gas exhaust passage 80c). By repeating this process multiple times, the air remaining in the cold storage component 40 can be replaced with the inert gas.

[0165] <Summary of Sixth Embodiment>

[0166] In the present embodiment, the pressing member 51 presses and fixes the plurality of battery cells 30 and the plurality of cold storage members 40 in the stacking direction. Furthermore, the beam 43 extends in the stacking direction, thereby bridging the mutually different walls. Here, if the plurality of battery cells 30 and the plurality of cold storage materials 42 are pressed and fixed by the pressing member 51, the support body 41 may be damaged. Therefore, by extending the beam 43 in the stacking direction and bridging the wall 411 as in the present embodiment, it is possible to suppress the support body 41 from being damaged.

[0167] In this embodiment, the inert gas is filled in the gap 412 together with the cold storage material 42. If the gap 412 is filled with the cold storage material 42, the beam 43 may be damaged when the volume of the cold storage material 42 expands. Therefore, the cold storage material 42 is not filled to the full, but filled with inert gas, thereby suppressing the damage of the beam 43. In addition, since the gap is filled with inert gas, the risk of combustion due to air can be reduced.

[0168] In the present embodiment, the support body 41 is provided with a gas injection passage 80a for filling the gap 412 with an inert gas. Thus, in the manufacturing process of the cold storage component 40, the inert gas can be injected from the gas injection passage 80a. Therefore, the air remaining in the cold storage component 40 can be squeezed out and discharged by the inert gas. That is, in the gap 412, the gas existing together with the cold storage material 42 can be replaced from air to the inert gas.

[0169] In the present embodiment, a filling passage 80b capable of filling the gap 412 with the cold storage material 42 is provided. Furthermore, the beam 43 is plate-shaped, and the plate surface of the beam 43 extends in the direction in which the filling passage 80b opens relative to the gap 412. When the cold storage material 42 is filled, in contrast to the present embodiment, if the plate surface of the beam 43 extends in a direction perpendicular to the direction in which the filling passage 80b opens relative to the gap 412, the cold storage material 42 flows in relative to the beam 43 when the cold storage material 42 is filled, and most of the pressure is applied to the beam 43. In contrast, in the present disclosure, the cold storage material 42 flows in from the filling passage 80b along the extending direction of the beam 43, and therefore most of the pressure is applied not to the beam 43 but to the wall 411. Thus, it is possible to prevent excessive pressure from being applied to the beam 43 and causing the beam 43 to be damaged.

[0170] In this embodiment, the inert gas is filled together with the cold storage material 42. Furthermore, the support body 41 includes a gas injection passage 80a and a filling passage 80b, and the gas injection passage 80a and the filling passage 80b are a common passage. Thus, the structure can be simplified compared to the case where the gas injection passage 80a and the filling passage 80b are separately provided.

[0171] In the present embodiment, the gap 412 includes a beam path 412a divided into a plurality of beam paths 412a and a connecting path 412b that connects the plurality of beam paths 412a to each other. When the cold storage material 42 is filled, the beam path 412a close to the opening of the filling path 80b among the plurality of beam paths 412a is filled with the cold storage material 42. Thereafter, if the cold storage material 42 is further filled, the cold storage material 42 flows into the adjacent beam path 412a through the connecting path 412b. That is, when the cold storage material 42 is filled into the gap 412 inside the cold storage component 40, the cold storage material 42 can be more efficiently distributed from one filling path 80b to the plurality of beam paths 412a. Thus, the filling operability of the cold storage material 42 can be improved.

[0172] In the present embodiment, the gas is filled in the gap 412 together with the cold storage material 42. Furthermore, the connecting path 412b makes the portions of the beam path 412a filled with the cold storage material 42 communicate with each other. After the filling operation of the cold storage material 42 is completed, the filling amount of each beam path 412a sometimes varies. Even in this case, since the connecting path 412b is located in the portion filled with the cold storage material 42, the cold storage material 42 passes through the connecting path 412b and is distributed due to its own weight as time passes. As a result, the amount of the cold storage material 42 in each beam path 412a becomes uniform, and the variation of the cooling efficiency can be suppressed.

[0173] <Modification>

[0174] Fig.23 is a diagram showing a modified example. Fig.23 In the embodiment, the passage portion 80 is omitted. Fig.23 In this way, the battery cell 30 is arranged adjacent to the cold storage component 40 in such a manner that the electrode terminals 31P and 31N are located below in the Z direction. In this modification, the downward direction in the Z direction represents the direction of gravity, and the upward direction in the Z direction represents the direction opposite to the direction of gravity. The gap 412 of the cold storage component 40 is filled with gas and cold storage material 42. The filled cold storage material 42 accumulates in the lower part of the cold storage component 40 due to gravity, while the gas accumulates in the upper part of the cold storage component 40. In this modification, the dimensions of the battery cell 30 and the cold storage component 40 in the Y direction and the Z direction are set to be approximately equal.

[0175] Positioning the electrode terminals 31P and 31N downward in the Z direction means that the electrode terminals 31P and 31N are arranged below half of the battery cell 30 . Preferably, the electrode terminals 31P and 31N are arranged below one-third of the battery cell 30 .

[0176] At this time, the vicinity of the electrode terminals 31P and 31N of the battery cell 30 (hereinafter also referred to as the vicinity of the electrode terminals) is adjacent to the portion filled with the cold storage material 42 in the cold storage component 40. The vicinity of the electrode terminals refers to the periphery of the portion adjacent to the electrode terminals 31P and 31N in the battery cell 30. The portion filled with the cold storage material 42 in the cold storage component 40 is configured to be adjacent to the portion of the battery cell 30 that becomes a high temperature (near the electrode terminals). In other words, the portion filled with gas in the cold storage component 40 is configured to be adjacent to the portion of the battery cell 30 that becomes a high temperature (near the electrode terminals). In addition, in this modified example, the dimensions of the battery cell 30 and the cold storage component 40 in the Y direction and the Z direction are approximately equal, but are not limited to this. As long as it is configured so that the vicinity of the electrode terminals of the battery cell 30 is adjacent to the portion filled with the cold storage material 42 in the cold storage component 40, the dimensions can be appropriately changed.

[0177] Due to the heat generated by the electrode terminals 31P and 31N of the battery cell 30, the vicinity of the electrode terminals of the battery cell 30 becomes high temperature. In addition, when the cold storage component 40 is filled with gas, the gas accumulates in the upper part of the cold storage component 40 due to buoyancy. Therefore, in the case where the battery cell 30 is arranged adjacent to the cold storage component 40 with the electrode terminals 31P and 31N located above, contrary to the present disclosure, there is a concern that the vicinity of the high-temperature electrode terminals is adjacent to the upper part of the cold storage component 40, which is the part where the gas is accumulated, and it may not be cooled sufficiently. Therefore, in this modified example, the battery cell 30 is arranged adjacent to the cold storage component 40 in such a manner that the electrode terminals 31P and 31N are located below. According to this modified example, it is easy to achieve that the vicinity of the electrode terminals of the battery cell 30 is not adjacent to the upper part of the cold storage component 40, which is the part filled with gas.

[0178] The battery cell 30 may be arranged adjacent to the cold storage member 40 so that the electrode terminals 31P and 31N are horizontally arranged. Fig.23 The battery cell 30 is rotated ±90 degrees on the YZ plane. That is, when the battery cell 30 is arranged adjacent to the cold storage component 40 in a horizontal manner, the electrode terminals 31P and 31N protrude in the Y direction. That is, the electrode terminals 31P and 31N protrude in a direction perpendicular to the direction in which the battery cell 30 and the cold storage component 40 are relative to each other and in a direction perpendicular to the up-down direction. In this case, the vicinity of the electrode terminals 31P and 31N of the battery cell is also arranged adjacent to the portion filled with the cold storage material 42 in the cold storage component 40, so the same effect as the above-mentioned modified example can be obtained.

[0179] The electrode terminals 31P and 31N protrude from the upper surface 30a, but the electrode terminals 31P and 31N do not have to protrude from the same surface. Alternatively, one of the electrode terminals 31P and 31N may protrude from the upper surface 30a, and the other may protrude from the bottom surface 30b. In this case, by arranging the battery cell 30 adjacent to the cold storage member 40 in a manner that the electrode terminals 31P and 31N are horizontally disposed, the same effect as the above-mentioned modified example can be obtained.

[0180] Placing the electrode terminals 31P and 31N horizontally means that the electrode terminals 31P and 31N are arranged below the upper 1 / 3 of the battery cell 30 .

[0181] The direction in which the pressing member 51 presses the battery cells 30 and the cold storage member 40 is not limited to the stacking direction, and the pressing member 51 may press and fix the battery cells 30 and the cold storage member 40 in other directions.

[0182] The gap 412 is filled with the inert gas and the regenerator material 42 , but the gap 412 may not be filled with the inert gas, and may be filled with a substance other than the inert gas (for example, air).

[0183] The plate surface of the beam 43 extends in the direction in which the filling passage 80 b opens relative to the gap 412 , but the present invention is not limited thereto. The plate surface of the beam 43 may extend in a direction perpendicular to the direction in which the filling passage 80 b opens relative to the gap 412 .

[0184] The gas injection passage 80a and the filling passage 80b may not be a common passage, but may be provided separately from the gas injection passage 80a and the filling passage 80b.

[0185] The gap 412 includes a communication path 412 b that connects the plurality of beam paths 412 a to one another, but the communication path 412 b may not be provided.

[0186] The communication paths 412 b may allow portions of the beam paths 412 a that are not filled with the cold storage material 42 to communicate with each other.

[0187] The battery cell 30 may be arranged adjacent to the cold storage member 40 so that the electrode terminals 31P and 31N are located upward in the Z direction.

[0188] (Other embodiments)

[0189] The disclosure in this specification and the drawings is not limited to the illustrated embodiments. The disclosure includes the illustrated embodiments and the variations made by those skilled in the art based on them. For example, the disclosure is not limited to the combination of parts and / or elements shown in the embodiments. The disclosure can be implemented through a variety of combinations. The disclosure can have additional parts that can be added to the embodiments. The disclosure includes a method in which parts and / or elements of the embodiments are omitted. The disclosure includes the replacement or combination of parts and / or elements between one embodiment and other embodiments. The disclosed technical scope is not limited to the description of the embodiments. The multiple technical scopes disclosed are shown by the description of the scopes claimed for protection, and should also be understood to include all changes within the meaning and scope equivalent to the description of the scopes claimed for protection.

[0190] The disclosure in the specification and drawings is not limited by the description of the scope of protection required. The disclosure in the specification and drawings includes the technical ideas recorded in the scope of protection required, and also involves more diverse and broader technical ideas than the technical ideas recorded in the scope of protection required. Therefore, it is possible to extract a variety of technical ideas from the disclosure in the specification and drawings without being limited to the description of the scope of protection required.

[0191] Where an element or layer is referred to as being "located above," "connected," "connected," or "bonded," then sometimes it is directly located above, connected, connected, or bonded to other elements or other layers, and there may also be intermediate elements or intermediate layers. Conversely, where an element is referred to as being "directly located above," "directly connected," "directly connected," or "directly bonded" to other elements or layers, there are no intermediate elements or intermediate layers. Other words used to describe the relationship between elements should also be used in the same manner (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.). Where used in this specification, the term "and / or" includes any and all combinations of one or more of the items listed in the association.

[0192] The number of battery cells 30 included in the battery pack 20 is not limited to the above example. For example, only one battery cell 30 may be included.

[0193] A portion of the cold storage member 40 may be in contact with the side surface 30 c of the battery cell 30 , and another portion may be in contact with the bottom surface 30 b .

[0194] <Disclosure of technical ideas)

[0195] The specification discloses multiple technical ideas recorded in the following multiple items. Some items are sometimes recorded in subsequent items by selectively referring to a multiple dependent form of a preceding item. Furthermore, some items are sometimes recorded by referring to a multiple dependent form of another multiple dependent form. These items recorded in multiple dependent forms define multiple technical ideas.

[0196] <Technical Thought 1>

[0197] A battery pack is mounted on an electric vehicle, comprising:

[0198] A battery cell 30; and

[0199] a cold storage member 40 for cooling the battery cells;

[0200] The cold storage member includes a support body 41, a cold storage material 42, and a beam 43. The support body has a wall defining a gap, the cold storage material is arranged in the gap and supported by the support body, and the beam bridges the wall.

[0201] The support body and the beam are formed of a material having a higher thermal conductivity than the cold storage material.

[0202] <Technical Thoughts 2>

[0203] The battery pack described in technical idea 1, wherein:

[0204] The walls are formed in pairs and include opposing walls facing each other,

[0205] The beams bridge pairs of the opposing walls,

[0206] At least one of the opposing walls is in direct or indirect contact with the battery cell.

[0207] <Technical Thought 3>

[0208] The battery pack described in technical idea 2, wherein:

[0209] The beam is a honeycomb structure, a fin shape, or a plurality of columns extending in one direction.

[0210] <Technical Thought 4>

[0211] A battery pack according to any one of technical concepts 1 to 3, wherein:

[0212] The battery cells are provided in plurality, and at least a portion of the cold storage member is disposed between adjacent battery cells and is sandwiched by the battery cells.

[0213] <Technical Thought 5>

[0214] A battery pack according to any one of technical concepts 1 to 3, wherein:

[0215] At least a portion of the cold storage member is in contact with a bottom surface of the battery cell.

[0216] <Technical Thought 6>

[0217] The battery pack according to any one of technical concepts 1 to 5, wherein:

[0218] The cold storage material is a latent heat cold storage material.

[0219] <Technical Thought 7>

[0220] The battery pack described in technical idea 6, wherein:

[0221] The phase transition temperature between the solid phase and the liquid phase in the latent heat storage material is set between 30°C and 60°C.

[0222] <Technical Thought 8>

[0223] The battery pack described in technical idea 6 or 7, wherein:

[0224] The latent heat storage material is a non-hydrate carbon compound.

[0225] <Technical Thought 9>

[0226] The battery pack described in technical idea 6 or 7, wherein:

[0227] The latent heat storage material is water-soluble and is adjusted to a pH value between 6 and 8.

[0228] <Technical Thought 10>

[0229] A battery pack according to any one of technical ideas 1 to 9, wherein:

[0230] The cold storage component has a plurality of beams.

[0231] The interval between adjacent beams is set between 1 mm and 10 mm.

[0232] <Technical Thought 11>

[0233] A battery pack according to any one of technical ideas 1 to 10, wherein:

[0234] The battery cell has electrode terminals 31P and 31N.

[0235] The cold storage component has a plurality of beams.

[0236] The closer to the electrode terminal, the narrower the interval between the adjacent beams.

[0237] <Technical Thoughts 12>

[0238] A battery pack according to any one of technical concepts 1 to 11, wherein:

[0239] At least a portion of the cold storage member is provided to be attachable to and detachable from the battery cell.

[0240] <Technical Thought 13>

[0241] A battery pack according to any one of technical concepts 1 to 12, wherein:

[0242] The plurality of battery cells and the plurality of cold storage members are alternately arranged in a predetermined stacking direction.

[0243] The battery pack includes a pressing member 51 that presses and fixes the battery cell and the cold storage member.

[0244] The beams bridge the walls by extending in the stacking direction.

[0245] <Technical Thought 14>

[0246] A battery pack according to any one of technical concepts 1 to 13, wherein:

[0247] The gap is filled with an inert gas together with the cold storage material.

[0248] <Technical Thought 15>

[0249] The battery pack described in technical idea 14, wherein:

[0250] The support body includes a gas injection passage 80 a for filling the gap with the inert gas.

[0251] <Technical Thoughts 16>

[0252] A battery pack according to any one of technical concepts 1 to 15, wherein:

[0253] The support body includes a filling passage 80b, and the filling passage can fill the cold storage material into the gap.

[0254] The beam is plate-shaped.

[0255] The deck of the beam extends in a direction of the filling passage relative to the void opening.

[0256] <Technical Thoughts 17>

[0257] A battery pack according to any one of technical concepts 1 to 13, wherein:

[0258] The inert gas and the cold storage material are filled in the gap.

[0259] The support body includes a gas injection passage for injecting the inert gas into the gap and a filling passage 80b for filling the gap with the cold storage material.

[0260] The gas injection passage and the filling passage are one common passage.

[0261] <Technical Thoughts 18>

[0262] A battery pack according to any one of technical concepts 1 to 17, wherein:

[0263] The gap includes a plurality of beam paths 412 a partitioned by the beam and a communication path 412 b connecting the plurality of beam paths to each other.

[0264] <Technical Thoughts 19>

[0265] The battery pack described in technical idea 18, wherein:

[0266] The communication passages are arranged at a plurality of different positions in a direction in which the cool storage material is filled into the beam path.

[0267] <Technical Thoughts 20>

[0268] The battery pack described in technical idea 18, wherein:

[0269] The gas and the cold storage material are filled in the gap together,

[0270] The communication path allows portions of the beam paths filled with the cold storage material to communicate with each other.

[0271] <Technical Thoughts 21>

[0272] A battery pack according to any one of technical ideas 1 to 20, wherein:

[0273] The gas and the cold storage material are filled in the gap together,

[0274] The battery cell has electrode terminals 31P and 31N.

[0275] The periphery of a portion of the battery cell where the electrode terminal protrudes is adjacent to a portion of the cold storage member filled with the cold storage material.< / evtol>

Claims

1. A battery pack mounted on an electric vehicle, characterized in that: have: A battery cell (30); and a cold storage component (40) for cooling the battery cells, The cold storage component comprises a support body (41), a cold storage material (42) and a beam (43), wherein the support body has a wall defining a gap, the cold storage material is arranged in the gap and supported by the support body, and the beam bridges the wall. The support body and the beam are formed of a material having a higher thermal conductivity than the cold storage material.

2. The battery pack according to claim 1, characterized in that: The walls are formed in pairs and include opposing walls facing each other, The beams bridge pairs of the opposing walls, At least one of the opposing walls is in direct or indirect contact with the battery cell.

3. The battery pack according to claim 2, characterized in that: The beam is a honeycomb structure, a fin shape, or a plurality of columns extending in one direction.

4. The battery pack according to claim 1 or 2, characterized in that: A plurality of the battery cells are provided. At least a portion of the cold storage member is disposed between the adjacent battery cells and is sandwiched by the battery cells.

5. The battery pack according to claim 1 or 2, characterized in that: At least a portion of the cold storage member is in contact with a bottom surface of the battery cell.

6. The battery pack according to claim 1, characterized in that: The cold storage material is a latent heat cold storage material.

7. The battery pack according to claim 6, characterized in that: The phase transition temperature between the solid phase and the liquid phase in the latent heat storage material is set between 30°C and 60°C.

8. The battery pack according to claim 6 or 7, characterized in that: The latent heat storage material is a non-hydrate carbon compound.

9. The battery pack according to claim 6 or 7, characterized in that: The latent heat storage material is water-soluble and is adjusted to a pH value between 6 and 8.

10. The battery pack according to claim 1 or 2, characterized in that: The cold storage component has a plurality of beams. The interval between adjacent beams is set between 1 mm and 10 mm.

11. The battery pack according to claim 1 or 2, characterized in that: The battery cell has electrode terminals (31P, 31N). The cold storage component has a plurality of beams. The closer to the electrode terminal, the narrower the interval between the adjacent beams.

12. The battery pack according to claim 1 or 2, characterized in that: At least a portion of the cold storage member is provided to be attachable to and detachable from the battery cell.

13. The battery pack according to claim 1, characterized in that: The plurality of battery cells and the plurality of cold storage members are alternately arranged in a predetermined stacking direction. The battery pack has a pressing component (51) which presses and fixes the battery cell and the cold storage component. The beams bridge the walls by extending in the stacking direction.

14. The battery pack according to claim 1 or 13, characterized in that: The gap is filled with an inert gas together with the cold storage material.

15. The battery pack according to claim 14, characterized in that: The support body includes a gas injection passage (80a) for filling the gap with the inert gas.

16. The battery pack according to claim 1 or 13, characterized in that: The support body includes a filling passage (80b) capable of filling the cold storage material into the gap. The beam is plate-shaped. The deck of the beam extends in a direction of the filling passage relative to the void opening.

17. The battery pack according to claim 1 or 13, characterized in that: The inert gas and the cold storage material are filled in the gap. The support body includes a gas injection passage and a filling passage (80b), wherein the gas injection passage can inject the inert gas into the gap, and the filling passage can fill the gap with the cold storage material. The gas injection passage and the filling passage are one common passage.

18. The battery pack according to claim 1 or 13, characterized in that: The gap includes a plurality of beam paths (412a) divided by the beam and a connecting path (412b) connecting the plurality of beam paths to each other.

19. The battery pack according to claim 18, characterized in that: The communication passages are arranged at a plurality of different positions in a direction in which the cool storage material is filled into the beam path.

20. The battery pack according to claim 18, characterized in that: The gas and the cold storage material are filled in the gap together, The communication path allows portions of the beam paths filled with the cold storage material to communicate with each other.

21. The battery pack according to claim 1, characterized in that: The gas and the cold storage material are filled in the gap together, The battery cell has electrode terminals (31P, 31N). The periphery of a portion of the battery cell where the electrode terminal protrudes is adjacent to a portion of the cold storage member filled with the cold storage material.

Images