JP7430248B2 - Energy storage device structure and heat dissipation method for energy storage device structure - Google Patents

Description

The present invention relates to a power storage device structure and a heat dissipation method for the power storage device structure.

Electric vehicles, which have been developed and improved in recent years, are equipped with a large number of power storage devices such as various storage batteries (for example, battery cells using various batteries such as lithium-ion secondary batteries) and capacitors, and are capable of charging and discharging. A large amount of heat is generated during the repeated process. Since heat generation accelerates the deterioration of the power storage device, it is important to maintain the temperature around the power storage device within an appropriate range in order to control the deterioration of the power storage device. Therefore, various techniques have been proposed for keeping the temperature around the power storage device within an appropriate range.

For example, in order to suppress thermal damage to a battery module, which is a type of electricity storage device, in Patent Document 1 below, in a battery stack in which prismatic batteries are stacked, batteries are placed between adjacent prismatic batteries in the stacking direction. A technique for providing a space separator has been disclosed. In this technology, as an example of an inter-battery separator, one having a laminated structure of a heat insulating member/thermal conductive member/insulating member is disclosed.

Additionally, Patent Document 2 below discloses a technology for controlling heat dissipation of a battery by transmitting heat generated from a plurality of adjacent batteries (battery cells) to a heat dissipation member attached to the upper part of the battery case. has been done. In this technique, examples have been disclosed in which metals such as aluminum, iron, stainless steel, and titanium are used as heat radiating members.

International Publication No. 2019/167689 Japanese Patent Application Publication No. 2013-109975

However, even if the techniques disclosed in Patent Document 1 and Patent Document 2 are used, there is still room for improvement in terms of more efficiently controlling the temperature around various power storage devices including battery cells. there were.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a power storage device structure and a power storage device that can more efficiently control the temperature around the power storage device. An object of the present invention is to provide a method for dissipating heat from a structure.

In order to solve the above problems, the inventors of the present invention conducted extensive studies and developed a carbon fiber reinforced plastic (CFRP) member (hereinafter simply referred to as "CFRP member") having anisotropic heat conduction characteristics. We came up with the idea of thermally connecting a battery (which may sometimes occur) to a power storage device to dissipate heat from the power storage device.
The gist of the present invention, which was completed based on this knowledge, is as follows.

(1) One or more power storage devices and a carbon fiber-reinforced plastic member having oriented carbon-reinforced fibers, wherein the carbon fiber-reinforced plastic member is arranged on at least one surface of the one or more power storage devices. arranged and thermally connected to the electricity storage device, at least one end of the carbon fiber-reinforced plastic member in the orientation direction of the carbon-reinforced fibers is such that the entire surface of the end is exposed to the atmosphere, or Or, at least a part of the end portion is in contact with at least one of the refrigerant or the heat radiation mechanism, and the end portion or the refrigerant is exposed in the atmosphere when the carbon fiber reinforced plastic member is viewed from above. Alternatively, the direction toward the heat dissipation mechanism is defined as the 0° direction, the direction perpendicular to the 0° direction is defined as the 90° direction, and the direction in which the carbon reinforced fibers included in the carbon fiber reinforced plastic member are drawn is 0°. An electricity storage device structure, wherein the 0° direction component in the stretching direction of the carbon reinforced fibers included in the entire carbon fiber reinforced plastic member is 40% or more when the directional component and the 90° direction component are respectively calculated. .
(2) The electricity storage device structure according to (1), wherein the carbon fiber reinforced plastic member is a metal laminated CFRP member in which a metal layer is provided on at least one surface of the carbon fiber reinforced plastic member.
(3) The power storage device structure according to (2), wherein the heat radiation mechanism is an aluminum heat sink or a cooling mechanism that passes a coolant through a metal block.
(4) The power storage device structure according to (2) or (3), wherein a plurality of the metal laminated CFRP members on which the power storage devices are arranged are present and connected in parallel to the heat dissipation mechanism.
(5) The electricity storage device according to any one of (2) to (4), wherein the electricity storage device is directly thermally connected to the carbon fiber reinforced plastic member of the metal laminated CFRP member. Energy storage device structure.
(6) The electricity storage device structure according to any one of (2) to (4), wherein the electricity storage device is directly thermally connected to the metal layer of the metal laminated CFRP member. body.
(7) The electricity storage device structure according to any one of (2) to (6), wherein the metal layer has a thickness of 5.0 μm to 1.5 mm.
(8) The electricity storage device structure according to any one of (2) to (7), wherein the carbon fiber reinforced plastic member has a thickness of 0.1 to 5.0 mm.
(9) The electricity storage device structure according to any one of (2) to (8), wherein the metal layer is a metal foil or metal plate made of copper, aluminum, iron, stainless steel, or titanium.
(10) The electricity storage device structure according to any one of (2) to (9), wherein the carbon reinforced fiber is a pitch-based carbon reinforced fiber.
(11) A plurality of the power storage devices are arranged to face each other, the plurality of power storage devices are thermally connected to the heat dissipation mechanism, and the carbon fiber reinforced plastic member is arranged to face the power storage devices. The device according to (1), wherein the device is provided on at least one surface facing the other adjacent electricity storage device, and is thermally connected to the heat dissipation mechanism. Energy storage device structure.
(12) The electricity storage device structure according to (11), wherein the carbon reinforced fiber is a pitch-based carbon reinforced fiber.
(13) The electricity storage device structure according to (11) or (12), wherein the heat dissipation mechanism is provided with a groove, and the carbon fiber reinforced plastic member is fitted into the groove.
(14) Any of (11) to (13), wherein a heat insulating member is provided between the electricity storage device provided with the carbon fiber reinforced plastic member and another electricity storage device adjacent to the electricity storage device. The electricity storage device structure according to item 1.
(15) In the adjacent electricity storage devices, the carbon fiber reinforced plastic member is provided on the side facing the other electricity storage device, and the pitch-based carbon reinforced plastic member is provided on the side of the electricity storage device. The carbon fiber reinforced plastic member having carbon reinforced fibers other than pitch-based carbon reinforced fibers is provided on the side of the other electricity storage device, (11) ) to (14).
(16) Any one of (11) to (15), wherein the heat dissipation mechanism is at least either a cooling device that cools the heat transferred from the electricity storage device or an electricity storage device case that houses the electricity storage device. 1. The electricity storage device structure according to item 1.
(17) Any one of (1) to (16), wherein the carbon fiber reinforced plastic member has a thermal conductivity of 50 to 300 W/m·K in a direction perpendicular to the surface normal direction. The electricity storage device structure described in .
(18) The carbon fiber reinforced plastic member is thermally connected to another member via at least one of an adhesive or grease having a thermal conductivity of 0.1 W/m·K or more. ) to (17).
(19) The electricity storage device structure according to any one of (1) to (18), wherein the electricity storage device is a battery cell.
(20) A carbon fiber-reinforced plastic member having oriented carbon-reinforced fibers is arranged on at least one surface of one or more power storage devices, and the carbon fiber-reinforced plastic member and the power storage device are thermally bonded. At least one end of the carbon fiber-reinforced plastic member in the direction of orientation of the carbon-reinforced fibers is exposed to the atmosphere, or at least a portion of the end is exposed to a refrigerant. Alternatively, when the carbon fiber reinforced plastic member is brought into contact with at least one of the heat dissipation mechanisms and the carbon fiber reinforced plastic member is viewed from above, the end exposed in the atmosphere or the direction toward the refrigerant or the heat dissipation mechanism is defined as the 0° direction. , when the direction perpendicular to the 0° direction is defined as the 90° direction, and the 0° direction component and the 90° direction component are respectively calculated with respect to the stretching direction of the carbon reinforced fibers included in the carbon fiber reinforced plastic member. A heat dissipation method for a power storage device structure, wherein the 0° direction component in the stretching direction of the carbon reinforced fibers included in the entire carbon fiber reinforced plastic member is 40% or more.

As explained above, according to the present invention, it becomes possible to control the temperature around the electricity storage device more efficiently.

FIG. 2 is an explanatory diagram for explaining findings obtained by the present inventors. It is a graph diagram for explaining the knowledge obtained by the present inventors. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram for explaining a metal laminated CFRP member according to a first embodiment of the present invention. FIG. 1 is a schematic diagram for explaining a metal laminated CFRP member according to a first embodiment. FIG. 2 is a schematic diagram for explaining the orientation direction of carbon-reinforced fibers in a CFRP member. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 1 is a schematic diagram for explaining a power storage device structure according to a first embodiment. FIG. 3 is an explanatory diagram for explaining a method for measuring thermal conductivity of a carbon fiber reinforced plastic member. FIG. 3 is an explanatory diagram for explaining a method for measuring thermal conductivity of a carbon fiber reinforced plastic member. FIG. 3 is an explanatory diagram for explaining a method of measuring thermal conductivity of adhesive and grease. FIG. 2 is an explanatory diagram schematically showing the configuration of a power storage device structure according to a second embodiment of the present invention. FIG. 7 is a schematic diagram for explaining a power storage device structure according to a second embodiment. FIG. 7 is a schematic diagram for explaining a power storage device structure according to a second embodiment. FIG. 7 is a schematic diagram for explaining a power storage device structure according to a second embodiment. FIG. 7 is a schematic diagram for explaining a power storage device structure according to a second embodiment. FIG. 7 is a schematic diagram for explaining a power storage device structure according to a second embodiment. FIG. 7 is a schematic diagram for explaining a power storage device structure according to a second embodiment. FIG. 7 is a schematic diagram for explaining a power storage device structure according to a second embodiment. FIG. 7 is a schematic diagram for explaining a power storage device structure according to a second embodiment. 3 is a graph diagram for explaining an example and a comparative example in Experimental Example 1. FIG. 3 is a graph diagram for explaining an example and a comparative example in Experimental Example 1. FIG. 3 is a graph diagram for explaining an example and a comparative example in Experimental Example 1. FIG. FIG. 7 is a graph diagram for explaining an example and a comparative example in Experimental Example 2. FIG. 7 is a graph diagram for explaining an example and a comparative example in Experimental Example 2. FIG. 7 is a graph diagram for explaining an example and a comparative example in Experimental Example 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Note that, in this specification and the drawings, components having substantially the same functional configurations are designated by the same reference numerals and redundant explanation will be omitted.

(Regarding findings obtained by the inventors)
Before explaining the power storage device structure and the heat dissipation method of the power storage device according to each embodiment of the present invention, the knowledge obtained through the verification conducted by the present inventors will be briefly explained with reference to FIGS. 1A and 1B. explain.
FIG. 1A is an explanatory diagram for explaining the findings obtained by the present inventors, and FIG. 1B is a graph diagram for explaining the findings obtained by the present inventors.

The present inventors prepared a heat dissipation mechanism as shown in FIG. 1A in order to study temperature management of a battery cell (more specifically, a lithium ion secondary battery) as an example of a power storage device. More specifically, a lithium ion secondary battery as an example of a power storage device was installed on the surface of an aluminum fin functioning as a heat dissipation mechanism via a heat dissipation sheet and a plastic resin. After that, the temperature of the aluminum fin changes depending on whether a thermal conductor is provided on the surface of the lithium-ion secondary battery or not, due to the temperature rise of the lithium-ion secondary battery during operation (discharging). Using a thermocouple, we measured whether the At this time, aluminum (Al) and a CFRP member were used as the heat conductor. Note that as the CFRP member, a unidirectional material in which carbon reinforcing fibers were oriented in the direction from the lithium ion secondary battery to the aluminum fins was used.

The obtained results are shown in FIG. 1B. In FIG. 1B, the horizontal axis is measurement time (seconds), and the vertical axis is aluminum fin temperature (° C.). The aluminum fin temperature shows a higher value when a heat conductor is installed compared to when a heat conductor is not installed. This result shows that by providing a heat conductor on the surface of the lithium ion secondary battery, more heat generated in the lithium ion secondary battery can be transferred to the aluminum fins.

Furthermore, considering the high thermal conductivity of various metals including Al, the temperature of the aluminum fan when Al is provided as a thermal conductor is higher than the temperature of the aluminum fan when CFRP members are provided. It was predicted that this would happen. However, as shown in FIG. 1B, the obtained measurement results showed that the aluminum fin temperature when the CFRP member was provided was higher than the aluminum fin temperature when Al was provided.

When the inventors considered this result, it was estimated that in the case of Al, the heat generated in the lithium ion secondary battery is radiated from the Al before it reaches the aluminum fins. On the other hand, in the case of CFRP members, due to the structure in which the carbon reinforced fibers, which are good thermal conductors, are buried in the matrix resin, there is not much heat dissipation before reaching the aluminum fins. It is presumed that more heat efficiently reached the aluminum fins.

In this way, it is considered that the CFRP member has a high thermal conductivity in the direction in which the carbon reinforced fibers are oriented, but a low thermal conductivity in the thickness direction of the CFRP member. Therefore, we were able to obtain the knowledge that by appropriately using CFRP members, it is possible to more easily manage the temperature of various power storage devices including lithium ion secondary batteries.

In addition, as mentioned above, in the direction where the thermal conductivity is anisotropic and the thermal conductivity is low, when a power storage device generates abnormal heat, it has the effect of preventing the heat from propagating to the neighboring power storage device. It is thought that there is. Therefore, the deterioration and ignition of the power storage device are suppressed, further increasing safety. This point of view is particularly important for large-sized batteries installed in vehicles. Note that "abnormal heat generation" here refers to a temperature higher than that during normal operation that occurs for some reason within the power storage device. For example, when a nail is inserted into the power storage device to cause a forced short circuit. These include rapid heat generation, local short circuits caused by abnormal parts of the electrodes or active materials, and temperature rises due to increases in resistance. When the heat generated by such abnormal heat generation propagates to an adjacent power storage device, it induces a temperature rise in the adjacent power storage device, causing deterioration and abnormal heat generation. Therefore, it is very important to prevent the above-mentioned heat propagation.

Below, the electricity storage device structure and the heat dissipation method of the electricity storage device structure according to each embodiment of the present invention, which were completed based on this knowledge, will be described in detail.

In the electricity storage device structure according to each embodiment of the present invention, when the carbon fiber reinforced plastic member is viewed from above, the end exposed in the atmosphere or the direction toward the refrigerant or the heat radiation mechanism is defined as the 0° direction. , the direction orthogonal to the 0° direction is defined as the 90° direction, and when calculating the 0° direction component and the 90° direction component in the stretching direction of the carbon reinforced fibers included in the carbon fiber reinforced plastic member, the carbon fiber The 0° direction component in the stretching direction of the carbon reinforced fibers contained in the entire reinforced plastic member is 40% or more.

Furthermore, in the electricity storage device structure according to each embodiment of the present invention, at least one end of the CFRP member in the orientation direction of the carbon-reinforced fibers is such that the entire surface of the end is exposed to the atmosphere, or the end is exposed to the atmosphere. At least a portion of the portion is in contact with at least either the refrigerant or the heat radiation mechanism.

The power storage device structures according to the embodiments of the present invention have the above-mentioned features, and thereby utilize the anisotropic heat conduction properties of the CFRP member to more efficiently control the temperature around the power storage device. It becomes possible to do so.

In addition, the electricity storage device structure according to each embodiment of the present invention can also realize further features as shown in each embodiment by further including the features shown in each embodiment below. becomes.

Here, in each embodiment of the present invention, "thermally connected" refers to a state of "connected so that heat conduction is possible." Moreover, the state in which "thermal conduction is possible" more specifically means that the thermal resistance value between two members connected to each other is 1.0 or less.

Hereinafter, power storage device structures according to each embodiment of the present invention will be described in more detail with reference to the drawings. Note that, unless otherwise specified in the following description, a part of the structure of the power storage device structure shown in one embodiment may be replaced with the other, within a range that does not impair the effects of the power storage device structure according to each embodiment. It is also possible to apply to the configuration of the power storage device structure shown in the embodiment.

≪First embodiment≫
As mentioned above, in order to control the deterioration of power storage devices, it is important to maintain the temperature around the power storage devices within an appropriate range. It is conceivable to use heat conductive members such as various metals in combination when transmitting heat to.

For example, if we think of simply attaching a heat conductive member to a power storage device, using metal materials such as copper or aluminum alone will result in heavy weight, and if we make the metal material thinner to reduce the weight, performance and rigidity will increase. becomes insufficient. If the rigidity is insufficient, problems may occur when connecting to a heat dissipation mechanism such as a water cooling mechanism or an air cooling mechanism, or the exposed metal material may break or bend.

Further, it is possible to use a CFRP member as the heat conductive member, but since the CFRP member is an expensive material, using the CFRP member alone may lead to an increase in the cost of the power storage device.

From this point of view, in the first embodiment described below, we came up with the idea of laminating a metal layer on at least one surface of a CFRP member to form a metal-laminated CFRP member, and realized an electricity storage device structure. Ta. This makes it possible to realize a power storage device structure that has both high thermal conductivity and low cost.

At this time, as a result of intensive study by the present inventors, by focusing on the arrangement of the metal laminated CFRP members, it was possible to not only control the temperature around the electricity storage device more efficiently, but also achieve better thermal performance. The inventors have come up with the idea that it is possible to provide a power storage device structure that exhibits conductivity while also being rigid, lightweight, and cost-effective. The first embodiment described below describes a power storage device structure that not only can control the temperature around the power storage device more efficiently but also exhibits superior thermal conductivity while also being rigid, lightweight, and cost-effective. , will be explained in detail.

(About the power storage device structure)
The power storage device structure according to the first embodiment of the present invention will be described in detail below with reference to FIGS. 2A to 12.
2A and 2B are schematic diagrams for explaining the metal laminated CFRP member according to this embodiment. FIG. 3 is a schematic diagram for explaining the orientation direction of carbon reinforced fibers in a CFRP member. 4A to 9 are schematic diagrams for explaining the electricity storage device structure according to this embodiment. FIGS. 10 and 11 are explanatory diagrams for explaining a method for measuring the thermal conductivity of a carbon fiber reinforced plastic member. FIG. 12 is an explanatory diagram for explaining a method for measuring the thermal conductivity of adhesives and grease.

The power storage device structure according to the first embodiment includes one or more power storage devices and a carbon fiber reinforced plastic member having oriented carbon reinforced fibers, and the carbon fiber reinforced plastic member includes one or more power storage devices. and is thermally connected to the electricity storage device, and at least one end of the carbon fiber-reinforced plastic member in the orientation direction of the carbon-reinforced fibers is such that the entire surface of the end is exposed to the atmosphere. The end portion is exposed or at least a part of the end portion is in contact with at least one of the refrigerant or the heat dissipation mechanism, and the end portion is exposed to the atmosphere when the carbon fiber reinforced plastic member is viewed from above. The direction toward the refrigerant or heat dissipation mechanism is defined as the 0° direction, the direction perpendicular to the 0° direction is defined as the 90° direction, and the 0° direction component is defined as the direction in which the carbon reinforced fibers included in the carbon fiber reinforced plastic member are drawn. In a power storage device structure in which the 0° direction component in the stretching direction of the carbon reinforced fibers included in the entire carbon fiber reinforced plastic member is 40% or more when calculating the 90° direction component and the 90° direction component, the carbon fiber reinforced plastic This embodiment embodies a configuration in which the member is a metal laminated CFRP member in which a metal layer is provided on at least one surface of the carbon fiber reinforced plastic member.

<Metal laminated CFRP member 10>
For convenience, the following description will be made with reference to the coordinate system shown in FIG. 2A.
The power storage device structure according to the present embodiment includes a power storage device such as various batteries such as a lithium ion secondary battery, a capacitor, and the like, and members provided in the power storage device. At this time, the electricity storage device structure according to this embodiment employs a specific CFRP member as shown in FIGS. 2A and 2B.

That is, in the electricity storage device structure according to the present embodiment, as schematically shown in FIG. 2A, a carbon fiber reinforced plastic (CFRP) member 111 containing carbon reinforced fibers and a A metal laminated CFRP member 110 having a metal layer 113 is used.

Here, in the CFRP member 111 according to the present embodiment, the orientation direction of the carbon reinforced fibers is a direction perpendicular to the surface normal direction of the CFRP member 111. For example, in the example shown in FIG. The reinforcing fibers are oriented in the x-axis direction of FIG. 2A.

Note that the orientation direction of the carbon-reinforced fibers is not the direction of each individual carbon-reinforced fiber included in the CFRP member 111, but the orientation direction of the carbon-reinforced fibers of the CFRP member 111 as a whole (in other words, the average direction). This is the orientation direction of carbon reinforced fibers when viewed macroscopically.

More specifically, when the CFRP member 111 is viewed from above (for example, the z-axis direction in FIG. 2A), the end exposed in the atmosphere or in the direction toward the refrigerant or the heat dissipation mechanism (for example, the z-axis direction in FIG. 2A) x-axis direction) is defined as the 0° direction, and a direction perpendicular to the 0° direction (for example, the y-axis direction in FIG. 2A) is defined as the 90° direction. Then, when calculating the 0° direction component and the 90° direction component with respect to the stretching direction of the carbon reinforced fibers included in the carbon fiber reinforced plastic member, the carbon reinforced fibers included in the entire carbon fiber reinforced plastic member are calculated. The 0° direction component in the stretching direction is 40% or more.

In this embodiment, when the proportion of the 0° direction component is less than 40%, the CFRP member 111 cannot exhibit the desired cooling performance. By setting the proportion of the 0° direction component to 40% or more, the CFRP member 111 can exhibit desired cooling performance. The proportion of the 0° direction component is preferably 50% or more, more preferably 60% or more, at which a normal cloth material can be used, and the upper limit thereof may be 100%.

Here, the stretching direction of the carbon reinforced fibers in the CFRP member 111 can be measured using a three-dimensional X-ray microscope system (X-ray CT system). For example, an X-ray CT image of the CFRP member 111 is acquired using Xradia520 manufactured by ZEISS, and the stretching direction of the carbon-reinforced fibers can be determined from the three-dimensional image obtained by reconstructing the image. Furthermore, by analyzing the reconstructed image, it is possible to calculate the ratio of the 0° direction component and the 90° direction component in the drawing direction of the carbon reinforced fiber. Hereinafter, a method for calculating the 0° direction component and the 90° direction component will be described in detail with reference to FIG. 3.

The proportion of the 0° direction component is calculated as follows. Below, an example will be shown in which the entire CFRP member 111 includes two types of fiber stretching directions. First, for each of the first stretching direction having an angle (acute angle) θ ₁ with the 0° direction and the second stretching direction having an angle (acute angle) θ ₂ with the 0° direction as shown in FIG. , using trigonometric functions to decompose it into a 0° direction component and a 90° direction component. As a result, the absolute value of the 0° direction component at each thickness position of the CFRP member 111 (for example, each position along the z direction in FIG. 2A), and the 90° direction component at each thickness position of the CFRP member 111. Calculate the absolute value of the value.

Next, by summing (integrating) the 0° direction components at each thickness position along the thickness direction of the CFRP member 111, the value of the 0° direction component for the entire CFRP member 111 is calculated. Similarly, by summing (integrating) the 90° direction components at each thickness position along the thickness direction of the CFRP member 111, the value of the 90° direction component for the entire CFRP member 111 is calculated. Then, the values of the 0° direction component and the 90° direction component of the entire CFRP member 111 calculated here are further summed, and the ratio of the 0° direction component of the entire CFRP member 111 to the total value is calculated. calculate.

In addition, when the CFRP member 111 has a laminated structure in which a plurality of CFRPs are laminated, the 0° direction component and 90° direction component at each thickness position described above are the 0° component and 90° direction component per layer. It can be thought of as a component.

For example, assume that the CFRP member 111 has a laminated structure composed of six layers of CFRP. In this case, for example, when the angle θ ₁ is 30°, cos 30° is a 0° direction component, and sin 30° is a 90° direction component. That is, the 0° direction component per layer is approximately 0.866, and the 90° direction component per layer is 0.5. When the CFRP member 111 has a six-layer structure, the 0° direction component of the entire layer is 5.2, and the 90° direction component is 3.0. The value of the 0° direction component of the entire CFRP member 111, 5.2, is approximately 63% of 8.2, which is the total value of the 0° direction component and the 90° direction component of the entire CFRP member 111. This is the proportion of the 0° direction component in the entire CFRP member 111. Note that when the stretching direction is the 0° direction, the value of the 0° direction component is cos 0°, that is, 1, and the value of the 90° direction component is sin 0°, that is, 0. Further, when the stretching direction is 90°, the value of the 0° direction component is cos90°, that is, 0, and the value of the 90° direction component is sin90°, that is, 1.

Note that if each layer of the CFRP member 111 having a laminated structure is formed with approximately the same thickness, calculation can be performed using the method described above. However, if each layer has a different thickness, each layer The above ratio is calculated using the thickness as a weight. For example, if the value of the 0° direction component of the kth layer from one side of the CFRP member 111 in which n layers are laminated is x _k and the thickness of this layer is t _k , then the value of 0 in the entire CFRP member 111 is The total value of the ° direction components is x ₁ ×t ₁ +...+x _n ×t _n . The total value of the 90° direction components can also be calculated in the same way.

Furthermore, in the metal laminated CFRP member 110 according to this embodiment, the metal layer 113 may be formed on both sides of the CFRP member 111, as shown in FIG. 2B.

As described above, the CFRP member 111 has a structure in which carbon reinforced fibers, which are good thermal conductors, are embedded in the matrix resin. Therefore, the CFRP member 111 has a characteristic that while it transfers heat well in the orientation direction of the carbon reinforced fibers, it is difficult to transfer heat in the thickness direction of the CFRP member 111 (for example, the z-axis direction in FIG. 2A). manifest. However, since heat transfer in the thickness direction of the CFRP member 111 is not completely blocked, heat can be transferred in the thickness direction over a certain amount of time. In addition, the heat transfer efficiency in the thickness direction of the CFRP member 111 is lower than that of various metals such as aluminum, so the heat being transferred is radiated midway compared to various metals such as aluminum. The phenomenon is suppressed.

Here, the thermal conductivity of the CFRP member 111 according to the present embodiment in the x-axis direction is preferably within the range of 50 to 300 W/m·K. When the thermal conductivity in the x-axis direction shown in FIG. 2A falls within the above range, heat generated in the power storage device 120 described below can be more reliably transmitted to the end of the CFRP member 111.

When the thermal conductivity in the x-axis direction in FIG. 2A is less than 50 W/m·K, heat generated in the electricity storage device 120 described later cannot be sufficiently transmitted to the end of the CFRP member 111. , there is a possibility that the power storage device 120 cannot be sufficiently cooled. The thermal conductivity of the CFRP member 111 in the x-axis direction is more preferably 100 W/m·K or more, and even more preferably 150 W/m·K or more.

On the other hand, those whose thermal conductivity in the x-axis direction exceeds 300 W/m·K are hardly manufactured on a commercial basis and are expensive, so the thermal conductivity in the x-axis direction of the CFRP member 111 is It is preferable that it is 300 W/m·K or less.

In general, carbon reinforced fibers used in carbon fiber reinforced plastics (CFRP) are broadly classified into pitch-based carbon reinforced fibers and PAN-based carbon reinforced fibers. In this embodiment, the CFRP member 111 preferably contains pitch-based carbon reinforced fibers. By using pitch-based carbon reinforced fibers, it is possible to achieve better heat transfer efficiency.

Furthermore, carbon reinforced fibers include carbon fibers that are continuously drawn (also called continuous fibers), such as carbon fibers that are cut into lengths of about 2 to 100 mm (also called chopped yarn). There are various types, including those containing carbon fibers (also called milled fibers) cut into lengths of about 0.05 to 0.30 mm. In this embodiment, any of these fibers can be used, or a combination of multiple types of fibers can be used.

Further, the matrix resin used for the CFRP member 111 may be a thermoplastic matrix resin or a thermosetting matrix resin, but is preferably a resin with high heat resistance. Here, "high heat resistance" means that the CFRP member 111 has a heat resistance that allows the shape of the CFRP member 111 to be maintained even when exposed to heat that can be generated by the power storage device 120. By using such a resin with high heat resistance, it is possible to prevent the performance of the electricity storage device structure according to the present embodiment from deteriorating.

Examples of the thermosetting matrix resin having heat resistance as described above include phenol resin, epoxy resin, and melamine resin. In addition, examples of the thermoplastic matrix resin having heat resistance as described above include polypropylene resin, nylon 12 resin, nylon 6 resin, polycarbonate resin, PEEK (polyether ether ketone) resin, and PBT (polybutylene terephthalate) resin. , PPS (polyphenylene sulfide) resin, phenoxy resin, and the like. Among the above matrix resins, those having particularly high heat resistance include epoxy resins, phenol resins, melamine resins, and PEEK resins.

In the CFRP member 111 according to the present embodiment, the reinforcing fiber density (VF: Volume Fraction) is, for example, in the range of 40 to 65% in the case of continuous fibers (fibers continuously connected from one end of the CFRP to the other end). It is preferable. Further, in the case of discontinuous fibers such as chopped yarn (25 to 100 mm length, etc.), it is preferable that the reinforcing fiber density is within the above range of 20 to 50%. This makes it possible to realize more efficient heat conduction while suppressing an increase in cost, and more reliably keeps the thermal conductivity in the direction toward the heat dissipation mechanism 140, which will be described later, within the range of the thermal conductivity described above. It becomes possible to do this. When the fibers used are continuous fibers, the reinforcing fiber density is more preferably within the range of 50 to 60%. Furthermore, when the fibers used are discontinuous fibers, the reinforcing fiber density is more preferably in the range of 30 to 45%.

Furthermore, by configuring the CFRP member 111 according to the present embodiment with unidirectional CFRP in which carbon-reinforced fibers are oriented in the x-axis direction in FIG. It becomes possible to transmit the signal to the end of the CFRP member 111.

On the other hand, in order to further improve the rigidity of the electricity storage device structure according to the present embodiment, CFRP using a cloth material, CFRP using a quasi-isotropic laminated material, and the above-mentioned unidirectional CFRP are used. The CFRP member 111 may be configured in combination.

Furthermore, when configuring the CFRP member 111, in addition to carbon reinforced fibers, at least one of glass fibers and aramid fibers may be further used. At this time, the matrix resin constituting the CFRP member 111 may contain glass fibers or aramid fibers in addition to carbon reinforced fibers. However, when manufacturing the CFRP member 111, a CFRP prepreg in which carbon reinforced fibers are held in a matrix resin and a CFRP prepreg in which glass fibers or aramid fibers are held in a matrix resin are prepared. It is easier to form the CFRP member 111 by laminating CFRP prepregs in a desired laminated state. At this time, it is preferable to use about one layer of CFRP prepreg using glass fiber or CFRP prepreg using aramid fiber.

Moreover, the metal layer 113 is provided on at least one surface of the CFRP member 111 as described above, as shown in FIGS. 2A and 2B. The metal layer 113 is preferably made of a metal that exhibits excellent thermal conductivity, can be processed to be thin, is not easily damaged in actual use, and is not economically difficult to obtain. Examples of such metals include copper, aluminum, iron, stainless steel, titanium, and alloys thereof.

Further, the metal layer 113 according to this embodiment is preferably a metal foil or metal plate made of copper, aluminum, iron, stainless steel, or titanium.

By providing such a metal layer 113 on at least one surface of the CFRP member 111, it is possible to ensure the rigidity of the metal laminated CFRP member 110 as a whole while reducing the thickness of the expensive CFRP. Further, by using the CFRP member 111 in combination, the thickness of the metal can be made thinner than when using the above-mentioned metal material alone, so it is also possible to reduce the weight of the electricity storage device structure. That is, by using the metal laminated CFRP member 110 according to this embodiment, it is possible to further improve rigidity, lightness, and cost efficiency while exhibiting excellent thermal conductivity.

In addition, in recent years, the electrification of automobiles has progressed, and there are concerns about the negative effects of magnetic fields and electromagnetic waves on automobile electronic devices.Especially in automobiles equipped with large batteries such as electric cars, large currents constantly flow during driving. Therefore, there is a strong need for electromagnetic shielding properties. In this respect, the metal laminated CFRP member 110 according to the present embodiment has an excellent electromagnetic wave shield because the metal layer 113 made of copper, aluminum, iron, stainless steel, or titanium is formed on the surface of the CFRP member 111. This makes it possible to further ensure the quality of the product. In other words, by using the metal laminated CFRP member 110 according to the present embodiment, it is possible to replace the two conventionally used members, the heat conductive member and the electromagnetic shielding member, with one member, resulting in excellent heat conduction. This makes it possible to further improve rigidity, lightness, and cost efficiency while exhibiting electromagnetic shielding properties and electromagnetic wave shielding properties. Note that the electromagnetic wave shielding property referred to here is focused on shielding property against electromagnetic waves belonging to the frequency band of 100 kHz to 100 GHz.

Here, the thickness d of the CFRP member 111 (thickness in the z-axis direction in FIGS. 2A and 2B) is preferably within the range of 0.1 to 5.0 mm. By setting the thickness of the CFRP member 111 within the above range, it becomes possible to more efficiently transmit heat generated in the power storage device 120 described below while ensuring rigidity, lightness, and cost efficiency. The thickness d of the CFRP member 111 is more preferably within the range of 0.4 to 2.5 mm.

Further, the thickness d _M of the metal layer 113 (thickness in the z-axis direction in FIGS. 2A and 2B) is preferably within the range of 5.0 μm to 1.5 mm per one side of the CFRP member 111. By setting the thickness _dM of the metal layer 113 within the above range, it becomes possible to further achieve rigidity, lightness, cost efficiency, and electromagnetic wave shielding properties. The thickness d _M of the metal layer 113 is more preferably in the range of 10.0 μm to 0.5 mm. If the thickness _dM is less than 5.0 μm, the effect of compounding the metal layer and CFRP will be weakened, which is undesirable, and if the thickness _dM exceeds 1.5 mm, the overall mass will increase. , which is not preferable because the characteristics of CFRP that achieve both rigidity and lightness cannot be utilized.

<About the electricity storage device structure 11>
The power storage device structure 11 according to the present embodiment is such that the metal laminated CFRP member 110 as described above is arranged on the surface of the power storage device, and the power storage device 120 and the metal laminated CFRP member 110 are thermally connected. .

As schematically shown in FIGS. 4A to 4D, this power storage device structure 11 has a power storage device 120 arranged on the surface of a CFRP member 110 (FIGS. 4A and 4B) having one metal layer 113. The electricity storage device 120 may be arranged on the surface of the CFRP member 110 (FIG. 4C) having two metal layers 113, or the CFRP member 110 may have two metal layers 113. It is also possible to interpolate the power storage device with the power storage device (FIG. 4D).

Here, various types of power storage devices can be used as the power storage device 120 according to the present embodiment. Examples of such power storage device 120 include a lithium ion secondary battery, a lithium ion capacitor, a lead acid battery, and the like. Further, the size and capacity of power storage device 120 are not particularly limited.

As shown in FIGS. 4A to 4D, the power storage device structure 11 according to the present embodiment transmits heat generated in the power storage device 120 from the metal layer 113 to the CFRP member 111, and It is characterized in that it is transmitted in the in-plane direction (the x-axis direction in FIGS. 4A to 4D).

Conventionally, when using a CFRP member as a heat conductive member, heat generated by an electricity storage device or the like was transferred in the thickness direction of the CFRP member (in other words, in the normal direction to the surface of the CFRP member). However, as shown in Figure 1B, the CFRP member exhibits anisotropic thermal conductivity in the orientation direction of the carbon-reinforced fibers. Thermal conductivity was not fully utilized.

In addition, in the power storage device structure 11 according to the present embodiment, the entire surface (the entire circumference and end surface) of at least one end of the metal laminated CFRP member 110 on the side where the power storage device 120 is arranged is exposed to the atmosphere. Or, at least a portion of the end portion is connected to or in contact with a refrigerant or a heat dissipation mechanism.

In the following, a case where the entire surface of at least one end of the metal laminated CFRP member 110 is exposed to the atmosphere will be described in detail with reference to FIGS. 4A to 4D.

When the entire surface of at least one end of the metal laminated CFRP member 110 is exposed to the atmosphere, even if the surface of the metal laminated CFRP member 110 is on the side where the power storage device 120 is arranged, for example, FIGS. 4A to 4D Like the area surrounded by the broken line in , there is a part that is not covered by the power storage device 120 and is exposed to the atmosphere (for example, the atmosphere). This makes it possible to utilize heat radiation from the surface of the metal layer 113 in addition to the in-plane heat transfer by the CFRP member 111, making it possible to achieve better thermal conductivity. In addition, since the metal laminated CFRP member 110 has rigidity ensured by the CFRP member 111 and the metal layer 113, deformation such as bending or bending occurs even in the exposed portion of the metal laminated CFRP member 110. Never.

Note that in FIGS. 4A to 4D, the power storage device 120 is arranged such that one end of the metal laminated CFRP member 110 in the x-axis direction is exposed to the atmosphere; Power storage device 120 may be arranged such that both ends in the axial direction are exposed to the atmosphere.

Furthermore, on the surface of the metal laminated CFRP member 110, the area ratio occupied by the power storage device 120 (coverage rate of the power storage device 120) is determined by the presence of a refrigerant or a heat dissipation mechanism in at least a portion of at least one end of the metal laminated CFRP member 110. For example, it is preferably within the range of 40% to 100%, taking into consideration the possibility that the By setting such an area ratio, it is possible to achieve both thermal conductivity and heat insulation. The area ratio occupied by the power storage device 120 on the surface of the metal laminated CFRP member 110 is more preferably within the range of 75 to 100%.

However, as shown in FIGS. 4A to 4D, when one end of the metal laminated CFRP member 110 in the x-axis direction is exposed to the atmosphere, efficient cooling is possible. Therefore, even if the area ratio occupied by power storage device 120 is less than 40%, the amount of expensive CFRP used can be reduced accordingly. As a result, in terms of overall strength including cost, even if the area ratio is 40% or more, it is superior to a structure in which one end in the x-axis direction is not exposed to the atmosphere.

In addition, when one end of the metal laminated CFRP member 110 in the x-axis direction is connected to or in contact with a refrigerant or a heat dissipation mechanism, the cooling efficiency is high. The lower limit can also be made smaller.

When placing the metal laminated CFRP member 110 according to this embodiment on the surface of the power storage device 120, a thermally conductive sheet (not shown) with excellent thermal conductivity is placed at the interface between the metal laminated CFRP member 110 and the power storage device 120. ) may be placed. By arranging the metal laminated CFRP member 110 on the surface of the power storage device 120 via such a thermally conductive sheet, it is possible to establish a thermal connection between the power storage device 120 and the metal laminated CFRP member 110 more reliably. becomes. As such a thermally conductive sheet, for example, a high thermal conductivity sheet EX10000F7 manufactured by Dexerials Co., Ltd. can be mentioned.

Further, when placing the metal laminated CFRP member 110 according to the present embodiment on the surface of the electricity storage device 120, for example, as schematically shown in FIG. Metal laminated CFRP member 110 may be thermally connected to power storage device 120 using an adhesive or at least one of grease 130 . The thermal conductivity of the adhesive or grease 130 is more preferably 3.0 W/m·K or more. By using such an adhesive or grease 130, it becomes possible to thermally connect the metal laminated CFRP member 110 to the power storage device 120 more reliably. Here, regarding the adhesive or grease 130 having thermal conductivity as described above, adhesives such as SX1008, SX1010, and RH96L manufactured by Cemedine Co., Ltd., and thermal conductive grease such as G-777 manufactured by Shin-Etsu Chemical Co., Ltd. can be exemplified. Furthermore, the adhesive or grease described above may be used in combination with various fillers and the like.

Furthermore, when placing the metal laminated CFRP member 110 according to the present embodiment on the surface of the power storage device 120, the metal laminated CFRP member 110 is fixed at a location (not shown) other than the power storage device 120, and then, The metal laminated CFRP member 110 may be in contact with the surface of the power storage device 120. Further, the metal laminated CFRP member 110 according to this embodiment may be fixed on the surface of the power storage device 120 using screws or various fixing jigs (not shown).

Next, a case where at least a portion of at least one end of the metal laminated CFRP member 110 is connected to or in contact with a refrigerant or a heat radiation mechanism will be described in detail. Note that also in the embodiment described below, it is possible to apply the adhesive or grease 130 as described above, or to apply the method of fixing the power storage device 120 as described above.

As schematically shown in FIG. 6A, the power storage device structure 1 according to the present embodiment has an end surface in the orientation direction of the carbon reinforced fibers of the metal laminated CFRP member 110 (an end surface in the x-axis direction in FIG. 6A). On the other hand, it is preferable that a heat radiation mechanism 140 is further provided. In other words, it is preferable that the heat dissipation mechanism 140 exists at the end of the CFRP member 111 in the stretching direction of the carbon reinforced fibers. By providing the heat dissipation mechanism 140 in such an arrangement, it becomes possible to utilize the anisotropic heat conduction characteristics of the CFRP member 111 more efficiently, and it becomes possible to control the temperature of the electricity storage device 120 with more precision. Become.

At this time, as shown in FIG. 6A, the heat dissipation mechanism 140 may be in direct contact with the end face of the metal laminated CFRP member 110 exposed in the atmosphere, or as shown in FIG. It may be connected to the heat dissipation mechanism 140. Furthermore, when at least one of the heat dissipation mechanism 140 and the refrigerant 150 is connected to the end surface of the metal laminated CFRP member 110, the entire end of the metal laminated CFRP member 110 is It does not need to be exposed in the atmosphere.

The heat dissipation mechanism referred to here is an aluminum heat sink or a cooling device that passes a coolant through a metal block. Specifically, it is a heat sink that attaches fins to an aluminum block and cools it by dissipating heat. Similar items, equipment that cools metal blocks by passing refrigerant through them, and similar items, and items that are connected to these and conduct heat (e.g., metal plates and pipes made of aluminum, copper, etc.) .

Further, when the refrigerant 150 is a liquid, it is water-cooled, and when it is a gas, it is air-cooled. Further, an adhesive or grease 130 having a thermal conductivity as described above may also function as a coolant 150. Note that the refrigerant refers to water, oil, or a gel-like substance, and includes a configuration in which these refrigerants are filled in a pipe or a pool, and the end portion is in direct contact with the refrigerant in such a state. . In the case of a gel-like substance, it can be used not only as a refrigerant but also as a heat transfer member to a heat radiation mechanism. In this case, the end portion may be in contact with only the gel material, or may be in contact with both the gel material and the heat dissipation mechanism.

Here, in FIGS. 6A to 6C, the power storage device 120 is thermally connected to the heat dissipation mechanism 140 via a set of metal laminated CFRP members 110. Further, as illustrated in FIG. 7A, multiple sets of metal laminated CFRP members 110 and power storage devices 120 can be connected to one heat dissipation mechanism while providing a gap between adjacent sets of metal laminated CFRP members 110 and power storage devices 120. 140 may be thermally connected. In other words, the electricity storage device structure 11 according to the present embodiment may be realized in which a plurality of sets of metal laminated CFRP members 110 and electricity storage devices 120 are arranged side by side in the heat dissipation mechanism 140.

Furthermore, although FIG. 7A illustrates a case where the power storage device 120 is not in contact with the heat dissipation mechanism 140, as shown in FIG. 7B, the power storage device 120 may be in contact with the heat dissipation mechanism 140. .

Further, in FIG. 7A, a case is illustrated in which a set of adjacent metal laminated CFRP members 110 and power storage devices 120 are arranged with a gap in between, but as shown in FIG. 7C, adjacent metal laminated CFRP members 110 and The sets of power storage devices 120 may be in contact.

Furthermore, as schematically shown in FIG. 7D, when multiple sets of metal laminated CFRP members 110 and power storage devices 120 are arranged side by side, various types of heat insulation are applied between adjacent metal laminated CFRP members 110 and power storage devices 120. At least either the member 160 or the stress relaxation member 170 may be provided.

By providing the heat insulating member 160, it becomes possible to block heat transfer between adjacent power storage devices 120, and it becomes possible to prevent thermal runaway of power storage devices 120.

Such a heat insulating member 160 can be constructed using various materials as long as they can block heat transfer between power storage devices 120. Examples of such materials include various resin materials such as polypropylene resin, polybutylene terephthalate resin, polycarbonate resin, epoxy resin, phenoxy resin, nylon resin, and polystyrene resin, nonwoven fabric, glass wool, rock wool, cellulose fiber, and urethane foam. , airgel, glass fiber reinforced resin, aramid fiber reinforced resin, etc.

Further, by providing the stress relaxation member 170, when stress that presses the power storage devices 120 arranged side by side acts, it is possible to relieve the local concentration of stress. Such a stress relaxation member 170 can be realized using a rubber material or a foam material. Specific examples of such stress relaxation members 170 include ethylene-based, propylene-based, butadiene-based, isopropylene-based, acrylic-based, silicone-based, urethane-based, styrene-based, polyurea-based, polyester-based elastomers, synthetic rubber, And these foams can be mentioned.

As shown in FIG. 8, when the metal laminated CFRP member 110 is thermally connected to the heat radiation mechanism 140, the metal laminated CFRP member 110 may be inserted into the heat radiation mechanism 140. The structure shown in FIG. 7 can be realized, for example, by providing a groove in the heat dissipation mechanism 140 and fitting the metal laminated CFRP member 110 into the groove. By connecting the metal laminated CFRP member 110 to the heat dissipation mechanism 140 as shown in FIG. 7, it is possible to increase the contact area between the metal laminated CFRP member 110 and the heat dissipation member 140, thereby cooling the electricity storage device 120 more reliably. It becomes possible to do so.

Furthermore, in order to further improve thermal conductivity, the contact area between the metal laminated CFRP member 110 and the heat dissipation mechanism 140 may be increased by making the end face of the metal laminated CFRP member 110 and the shape of the groove oblique. . Furthermore, the contact area between the metal laminated CFRP member 110 and the heat dissipation mechanism 140 may be increased by increasing the roughness of the end face of the metal laminated CFRP member 110 (roughening the end face roughness). For example, by changing the shape so that the angle between the inclined surface and the end surface of the heat dissipation mechanism 140 is 15° to 45°, the power storage device 120 can be cooled more reliably.

When thermally connecting the metal laminated CFRP member 110 according to this embodiment to the heat dissipation mechanism 140, the metal laminated CFRP member 110 may be brought into direct contact with the heat dissipation mechanism 140, as shown in FIG. 6A etc. As schematically shown in FIG. 9, a thermally conductive sheet 180 having excellent thermal conductivity may be disposed at the interface between the metal laminated CFRP member 110 and the heat dissipation mechanism 140. By arranging the metal laminated CFRP member on the surface of the heat dissipation mechanism 140 via such a thermally conductive sheet 180, the thermal connection between the heat dissipation mechanism 140 and the metal laminated CFRP member 110 is established more reliably, and power storage It becomes possible to cool the device 120 more reliably. An example of such a thermally conductive sheet 180 is a high thermal conductivity sheet EX10000F7 manufactured by Dexerials Co., Ltd.

In addition, in FIGS. 5 to 9, the explanation was given while taking as an example the power storage device structure having the laminated structure illustrated in FIG. 4A, but the power storage device having the laminated structure illustrated in FIGS. 4B, 4C, and 4D Similar implementation is possible for structures.

In addition, in order to heat the power storage device 120 to a temperature suitable for the operation of the power storage device 120 when the power storage device 120 is excessively cooled, a temperature control device that has both a heat radiation function and a heating function may be used instead of the heat radiation mechanism 140 described above. A control mechanism may also be provided. This enables more sophisticated temperature control of power storage device 120.

Next, a method for measuring the thermal conductivity of the CFRP member 111 according to this embodiment will be briefly described with reference to FIGS. 10 and 11.
In this embodiment, the thermal conductivity of the CFRP member 111 is measured by a straight fin temperature distribution fitting (SFTF) method.

Here, if the metal laminated CFRP member 110 is already disposed on the surface of the power storage device 120, the metal laminated CFRP member 110 is removed from the surface of the power storage device 120, and the metal layer 113 is further removed. , measure thermal conductivity. Specifically, when the metal laminated CFRP member 110 is in contact with the power storage device 120 via adhesive or grease, the metal laminated CFRP member 110 is in contact with the power storage device 120 in the vertical direction (z-axis direction in FIG. 2A). By peeling off the metal layer 113, wiping off the adhesive or grease, and then peeling off the metal layer 113, it can be used for measurement. Further, when the metal laminated CFRP member 110 is bonded to the power storage device 120 with an adhesive, the metal laminated CFRP member 110 is peeled off from the power storage device 120 using a tool such as a scraper, and the metal layer 113 is further peeled off. Thereafter, the surface where the metal layer 113 was present is polished to expose the surface of the CFRP member 111 and smooth the surface.

Thereafter, the surface closest to the surface of power storage device 120 is set as the measurement surface, and all regions except this measurement surface and the region into which the heat flow is input are covered with a heat insulating material. Thereby, a test piece of the CFRP member 111 to be subjected to the SFTF method can be obtained.

FIG. 10 is an explanatory diagram for explaining the principle of the SFTF method.
One end of a flat plate specimen with length Lt [m], cross-sectional area A [m ² ] = H x t, and peripheral length P [m] = 2 x (Lt + H + t) as shown in the upper part of Fig. 10. Regarding the test piece at steady state when one end is heated and the other end is cooled, the boundary temperature T ₀ =T _x0 at the heat flow input part and the temperature rise distribution T _i (i= 1 to n: number of temperature measurement points).

On the other hand, the temperature distribution analytical formula for the straight fin that gives the analytical solution T _xi regarding the temperature distribution of the straight fin is given by the following formula (101) using the boundary conditions of fixed temperature at one end and heat insulation at one end of the test piece. . Therefore, the obtained measured value T _xi is compared with the analytical solution Tx of the temperature rise of the straight fin given by the equation (101), and the standard deviation σ specified by the following equation (103) is calculated, The parameter m in the analytical formula is determined so that this standard deviation is minimized.

Further, the in-plane thermal conductivity (thermal conductivity in the length Lt direction in FIG. 10) of the sample of interest is expressed as k _p . In this case, the parameter m in the analytical equation expressed by equation (101) is expressed as the following equation (105) using the average heat transfer coefficient h _m from the test piece surface to the surrounding air. .

Further, the average heat transfer coefficient h _m is expressed as the following equations (107) to (111) using the theoretical equations of the vertical plate natural convection heat transfer coefficient and the radiation heat transfer coefficient. Here, in the following equations (107) to (111), h _nm is the natural convection heat transfer coefficient for a vertical flat plate of height H, and h _rm is the radiation heat transfer coefficient from the surface with emissivity ε. It is. Moreover, ka _, v _a , β, and Pr are the thermal conductivity, kinematic viscosity coefficient, expansion coefficient, and Prandtl number of air, respectively. Furthermore, g is the gravitational acceleration, and σ' is the Stefan-Boltzmann constant (=5.67×10 ⁻⁸ W/m ² ·K ⁴ ). T _m and T _a are the average temperature of the test piece and the outside temperature, respectively, expressed in absolute temperature. ΔTm is the average temperature rise of the test piece, and can be determined from ΔT ₀ ·φ using the fin efficiency φ (0.8) and the temperature increase ΔT ₀ at x=0.

When measuring the thermal conductivity of an actual CFRP member, the target CFRP member is cut out into a size of 20 mm wide x 200 mm long, and then a laminated structure as shown in Fig. 11 is constructed. A heater is installed at one end, and the heater output is set to 1.6W at 10V. After that, the in-plane temperature distribution of the CFRP member is photographed with a thermo camera, the obtained thermal image is converted into a temperature distribution, and the relationship between the test length and the surface temperature is confirmed. The thermal conductivity of the CFRP member of interest can be obtained by analyzing the relationship between the obtained test length and surface temperature using the linear fin temperature distribution fitting method described above.

Further, the thermal conductivity of adhesives and greases can be measured by the following thermal resistance measurement method based on ASTM5470.
As shown in the diagram on the upper left side of FIG. 12, the sample of interest is sandwiched between the upper meter bar and the lower meter bar, and power is applied to the heater on the upper meter bar side. On the other hand, the test head on the lower meter bar side is maintained at a constant temperature by water cooling or other methods. Then, determine the thermal resistance of the sample from the relationship between the positions of the upper and lower meter bars and the temperature. Specifically, thermocouples are attached to the positions indicated by T1 to T4 in the figure, and the surface temperature on the upper meter bar side of the sample is calculated based on the temperature gradient calculated from the temperatures obtained at T1 to T2. do. Furthermore, the surface temperature of the sample on the lower meter bar side is calculated based on the temperature gradient calculated from the temperatures obtained at T3 to T4. Thereby, the temperature difference ΔT inside the sample is calculated. Further, by using the amount of heat generated from the heater Q [W], the thermal resistance of the sample can be determined.

Calculate the thermal resistance of the sample as described above while changing the sample thickness, and plot the obtained results on a coordinate plane defined by the sample thickness and thermal resistance as shown in the lower part of Figure 12. do. Thereafter, the distribution of the obtained plot is linearly approximated by the least squares method, and the slope of the straight line is calculated. The reciprocal of the obtained slope becomes the thermal conductivity of the sample of interest.

Unlike the transistor method or model heater method, the thermal conductivity measurement method described above allows for changing the applied pressure on the upper meter bar side, making it possible to evaluate thermal resistance against applied pressure with good reproducibility. It is possible to do so. In actual measurements, thin films with thicknesses of 0.5 mm, 1.0 mm, and 1.5 mm are prepared and cut into 20 mm square pieces. Thereafter, the cut sample may be placed between meter bars and measured. At this time, the material of the meter bar is SUS304 (20 mm square), and the load at the time of measurement is 3 kg/cm ² . Then, the slope may be calculated from the relationship between the thermal resistance and the thickness, and the thermal conductivity may be calculated from the reciprocal of the slope.

Alternatively, if only a small amount of the adhesive or grease of interest is obtained, the adhesive or grease of interest is dissolved in an appropriate organic solvent, and the undissolved filler particles are extracted. The extracted filler particles are subjected to component analysis using fluorescent X-rays and crystal structure analysis using X-ray diffraction to identify the type of filler particles. Regarding the composition of the matrix resin, the type of matrix resin is identified by observing the obtained resin solution using infrared spectroscopy. Furthermore, the thermal conductivity can be calculated from the extracted filler amount and matrix amount using the following equation (121).

Here, in the following equation (121), λ _matrix is the thermal conductivity of the matrix resin, λ _filler is the thermal conductivity of the filler particles, and λ _composite is the thermal conductivity of the composite. Moreover, φ is the content (volume fraction) of the filler, and x is the shape factor of the filler (when it is a perfect sphere, it is minimum at x=2).

The electricity storage device structure 1 according to the present embodiment has been described in detail above with reference to FIGS. 2A to 12.

(About the manufacturing method of the electricity storage device structure)
The electricity storage device structure as explained above can be manufactured as follows. First, CFRP prepreg containing predetermined carbon reinforcing fibers and matrix resin is prepared, and a predetermined number of sheets are laminated to obtain a desired thickness. Thereafter, the obtained laminated prepreg is hot press molded or autograve molded to form a CFRP member. A metal laminated CFRP member is obtained by further arranging a metal material (for example, a metal foil or a metal plate) as described above on the surface of the obtained CFRP member.

The obtained metal laminated CFRP member is placed on the surface of the electricity storage device using adhesive or grease as necessary, and further, if necessary, a coolant or heat dissipation is applied to the end of the metal laminated CFRP member. Install a mechanism. Thereby, the electricity storage device structure according to this embodiment can be manufactured.

The power storage device structure and the heat dissipation method for the power storage device structure according to the first embodiment of the present invention have been described in detail above with reference to FIGS. 2A to 12.

≪Second embodiment≫
When various power storage devices are installed in an electric vehicle or the like, there is a high possibility that a plurality of power storage devices will be used. In this case, even if the technology disclosed in Patent Document 1 and Patent Document 2 is used, it is possible to efficiently reduce the temperature around a plurality of power storage devices that are adjacent to each other, while ensuring safety in the event of abnormal heat generation of the power storage devices. There was still room for improvement from the perspective of ensuring security.

From this point of view, in the second embodiment described below, in a situation where a plurality of power storage devices exist next to each other, the temperature around the plurality of power storage devices that are adjacent to each other can be cooled more efficiently. We focused on the power storage device structure and its heat dissipation method. With the power storage device structure according to the second embodiment described below, it is possible to more efficiently cool down the temperature around a plurality of adjacent power storage devices.

(About the power storage device structure)
Hereinafter, a power storage device structure according to a second embodiment of the present invention will be described in detail with reference to FIGS. 13 to 19.
FIG. 13 is an explanatory diagram schematically showing the configuration of the battery cell cooling mechanism according to this embodiment. 14 to 19 are schematic diagrams for explaining the battery cell cooling mechanism according to this embodiment.

The power storage device structure according to the second embodiment includes a plurality of power storage devices and a carbon fiber reinforced plastic member having oriented carbon reinforced fibers, and the carbon fiber reinforced plastic member includes at least one of the plurality of power storage devices. The carbon fiber reinforced plastic member is disposed on one surface and is thermally connected to the electricity storage device, and at least one end of the carbon fiber reinforced plastic member in the direction of orientation of the carbon reinforced fibers is exposed entirely to the atmosphere. Or, at least a part of the end portion is in contact with at least one of the refrigerant or the heat dissipation mechanism, and when the carbon fiber reinforced plastic member is viewed from above, the end portion or the refrigerant or the end portion is exposed in the atmosphere. The direction toward the heat dissipation mechanism is defined as the 0° direction, and the direction perpendicular to the 0° direction is defined as the 90° direction. In a power storage device structure in which the 0° direction component in the stretching direction of the carbon reinforced fibers included in the entire carbon fiber reinforced plastic member is 40% or more when the ° direction component is calculated, a plurality of power storage devices A plurality of power storage devices are arranged to face each other and are thermally connected to the heat dissipation mechanism, and the carbon fiber reinforced plastic member is connected to at least one of the plurality of power storage devices and other adjacent power storage devices. This embodiment embodies a configuration in which the heat dissipation mechanism is provided on at least one surface facing the heat dissipation mechanism and is thermally connected to the heat dissipation mechanism.

For convenience, the following description will be made with reference to the coordinate system shown in FIG. 13.
The power storage device structure according to this embodiment functions as a cooling mechanism for cooling a plurality of power storage devices (for example, battery cells). As schematically shown in FIG. 13, this power storage device structure 21 includes a plurality of battery cells 210, which are an example of a plurality of power storage devices, and a plurality of battery cells 210 arranged along the x-axis direction. A thermal cooling mechanism 220 is provided on at least one surface facing another adjacent battery cell 210 with respect to at least one or more of the plurality of battery cells 210. a carbon fiber reinforced plastic (CFRP) member 230 thermally connected to 220 .

As the battery cell 210, it is possible to use various battery cells that store and release electrical energy. Examples of such battery cells 210 include various lithium ion secondary batteries, nickel hydride batteries, nickel cadmium batteries, and the like. A plurality of such battery cells 210 are arranged with predetermined gaps provided, for example, along the x-axis direction in FIG. 13 in order to realize a desired amount of electrical storage. The battery cell 210 may be exposed or housed in a container such as a battery case.

Thermal cooling mechanism 220 is an example of a heat dissipation mechanism, and is a member that cools heat transferred from various members that are thermally connected. This thermal cooling mechanism 220 may be one that cools the heat transferred from various members using various refrigerants such as water, such as a cooling device that passes a refrigerant through a metal block. . Alternatively, it may be a heat sink made of aluminum (more specifically, an aluminum fin) that releases heat transferred from various members to the outside of the power storage device structure 21. Further, the thermal cooling mechanism 220 may be a device equipped with a thermal cooling function, such as a battery case (accommodating the battery cell 210) that is thermally connected to the various cooling devices described above. It may be a member. Note that the refrigerant refers to water, oil, or a gel-like substance, and in the case of a gel-like substance, it can be used not only as a refrigerant but also as a heat transfer member.

The heat generated in the plurality of battery cells 210 is transmitted directly from the battery cells 210 to the thermal cooling mechanism 220, or is transmitted to the thermal cooling mechanism 220 via a CFRP member 230, etc., which will be described in detail, and is transferred to the electricity storage device structure. It is released to the outside of 21.

The CFRP member 230 functions as a thermal conductor for transmitting heat generated in the battery cell 210 to the thermal cooling mechanism 220. As described above, the CFRP member 230 has a structure in which carbon reinforced fibers, which are good thermal conductors, are embedded in the matrix resin. Therefore, the CFRP member 230 exhibits a characteristic that, while it transfers heat well in the orientation direction of the carbon-reinforced fibers, it is difficult to transfer heat in the thickness direction of the CFRP member 230. However, since heat transfer in the thickness direction of the CFRP member 230 is not completely blocked, heat can be transferred in the thickness direction over a certain amount of time. In addition, the heat transfer efficiency in the thickness direction of the CFRP member 230 is lower than that of various metals such as aluminum, so the heat being transferred is radiated midway compared to various metals such as aluminum. The phenomenon is suppressed.

Here, the thermal conductivity of the CFRP member 230 according to the present embodiment in the direction toward the thermal cooling mechanism 220 (z-axis direction in FIG. 13) is preferably within the range of 50 to 300 W/m·K. When the thermal conductivity in the direction toward the thermal cooling mechanism 220 is within the above range, the heat generated in the battery cell 210 can be more reliably transferred to the thermal cooling mechanism 220.

If the thermal conductivity in the direction toward the thermal cooling mechanism 220 is less than 50 W/m·K, the heat generated in the battery cell 210 cannot be sufficiently transferred to the thermal cooling mechanism 220, and the battery cell 210 may not be able to cool down sufficiently. The thermal conductivity of the CFRP member 230 in the direction toward the thermal cooling mechanism 220 is more preferably 100 W/m·K or more, and even more preferably 150 W/m·K or more.

On the other hand, those whose thermal conductivity in the direction toward the thermal cooling mechanism 220 exceeds 300 W/m·K are hardly manufactured on a commercial basis and are expensive, so the thermal cooling mechanism 220 of the CFRP member 230 is The thermal conductivity in the direction is preferably 300 W/m·K or less.

As mentioned in the first embodiment, carbon reinforced fibers used in carbon fiber reinforced plastics (CFRP) are generally classified into pitch-based carbon reinforced fibers and PAN-based carbon reinforced fibers. The carbon fiber reinforced plastic member 230 according to this embodiment preferably contains pitch-based carbon reinforced fibers. By using pitch-based carbon reinforced fibers, it is possible to achieve better heat transfer efficiency.

Furthermore, carbon reinforced fibers include carbon fibers that are continuously drawn (also called continuous fibers), such as carbon fibers that are cut into lengths of about 2 to 100 mm (also called chopped yarn). There are various types, including those containing carbon fibers (also called milled fibers) cut into lengths of about 0.05 to 0.30 mm. In this embodiment, any of these fibers can be used, or a combination of multiple types of fibers can be used.

Further, the matrix resin used for the CFRP member 230 may be a thermoplastic matrix resin or a thermosetting matrix resin, but is preferably a resin with high heat resistance. Here, "high heat resistance" means that the CFRP member 230 has heat resistance to the extent that it can maintain its shape even when exposed to heat that can be generated by the battery cells 210. By using such a resin with high heat resistance, it is possible to prevent the performance of the power storage device structure 21 from deteriorating and achieve more reliable cooling of the battery cells.

Examples of the thermosetting matrix resin having heat resistance as described above include phenol resin, epoxy resin, and melamine resin. In addition, examples of the thermoplastic matrix resin having heat resistance as described above include polypropylene resin, nylon 12 resin, nylon 6 resin, polycarbonate resin, PEEK (polyether ether ketone) resin, and PBT (polybutylene terephthalate) resin. , PPS (polyphenylene sulfide) resin, phenoxy resin, and the like. Among the above matrix resins, those having particularly high heat resistance include epoxy resins, phenol resins, melamine resins, and PEEK resins.

In the CFRP member 230 according to the present embodiment, the reinforcing fiber density (VF: Volume Fraction) is, for example, within the range of 40 to 65% in the case of continuous fibers (fibers continuously connected from one end of the CFRP to the other end). In the case of discontinuous fibers such as chopped yarn (25 to 100 mm length, etc.), it is preferably within the range of 20 to 50%. By setting the reinforcing fiber density within the above range, it is possible to achieve more efficient heat conduction while suppressing an increase in cost, and the thermal conductivity in the direction toward the thermal cooling mechanism 220 is more reliable. It is possible to keep the thermal conductivity within the above-mentioned range. The reinforcing fiber density is more preferably within the range of 50 to 60% when the fibers used are continuous fibers, and more preferably within the range of 30 to 45% when the fibers are discontinuous fibers.

Further, in the CFRP member 230 according to the present embodiment, the carbon reinforced fibers are oriented in the direction toward the thermal cooling mechanism 220 (the z-axis direction in FIG. 13).

Here, the orientation direction of carbon-reinforced fibers is not the direction of each individual carbon-reinforced fiber included in the CFRP member 230, but the orientation direction of the carbon-reinforced fibers of the CFRP member 230 as a whole (in other words, the average (orientation direction of carbon-reinforced fibers when viewed macroscopically).

More specifically, when the CFRP member 230 is viewed from above (for example, the x-axis direction in FIG. 13), the end exposed in the atmosphere or in the direction toward the refrigerant or the heat dissipation mechanism (for example, in the direction of the heat dissipation mechanism in FIG. 13) z-axis direction) is defined as the 0° direction, and a direction perpendicular to the 0° direction (for example, the y-axis direction in FIG. 13) is defined as the 90° direction. Then, when calculating the 0° direction component and the 90° direction component with respect to the stretching direction of the carbon reinforced fibers included in the carbon fiber reinforced plastic member, the carbon reinforced fibers included in the entire carbon fiber reinforced plastic member are calculated. The 0° direction component in the stretching direction is 40% or more.

In this embodiment, if the proportion of the 0° direction component is less than 40%, the CFRP member 230 cannot exhibit the desired cooling performance. By setting the proportion of the 0° direction component to 40% or more, the CFRP member 230 can exhibit desired cooling performance. The proportion of the 0° direction component is preferably 50% or more, more preferably 60% or more, at which a normal cloth material can be used, and the upper limit thereof may be 100%.

Note that the ratio of the 0° direction component as described above can be specified in the same manner as the method described in the first embodiment.

Thereby, the heat generated in the battery cells 210 can be more reliably transferred to the thermal cooling mechanism 220. Furthermore, by configuring the CFRP member 230 according to the present embodiment with unidirectional CFRP in which carbon-reinforced fibers are oriented in the direction toward the thermal cooling mechanism 220, heat generated in the battery cell 210 can be more reliably dissipated. It becomes possible to transmit the heat to the cooling mechanism 220.

On the other hand, in order to further improve the rigidity of the power storage device structure 21 and the protection of the battery cells 210, the CFRP member 230 may be constructed using CFRP using a cloth material or CFRP using a quasi-isotropic laminated material. You can.

Further, when configuring the CFRP member 230, in addition to carbon reinforced fibers, at least one of glass fibers and aramid fibers may be further used. At this time, the matrix resin constituting the CFRP member 230 may contain glass fibers or aramid fibers in addition to carbon reinforced fibers. However, when manufacturing the CFRP member 230, a CFRP prepreg in which carbon reinforced fibers are held in a matrix resin and a CFRP prepreg in which glass fibers or aramid fibers are held in a matrix resin are prepared. It is convenient to stack CFRP prepregs in a desired stacked state and then form the CFRP member 230. At this time, it is preferable to use about one layer of CFRP prepreg using glass fiber or CFRP prepreg using aramid fiber.

The CFRP member 230 as described above, as illustrated in the second battery cell 210 from the left in FIG. It is provided on at least one surface and is thermally connected to the thermal cooling mechanism 220 . Thereby, heat generated in the battery cell 210 provided with the CFRP member 230 can be transferred to the thermal cooling mechanism 220 to cool the battery cell 210.

Further, the CFRP member 230 may be provided on two surfaces facing other adjacent battery cells 210, as illustrated in the second battery cell 210 from the right in FIG. Furthermore, as illustrated in FIG. 14, the CFRP member 230 may be provided for all of the plurality of battery cells 210.

Here, in this embodiment, the thickness of the CFRP member 230 (thickness in the x-axis direction in FIG. 13) is preferably within the range of 0.1 to 5.0 mm. By setting the thickness of the CFRP member 230 within the above range, it becomes possible to more efficiently transfer the heat generated in the battery cell 210 to the thermal cooling mechanism 220. In the CFRP member 230 provided on the surface of the battery cell, the closer the member is to the thermal cooling mechanism 220, the more the amount of heat transferred from the battery cell 210 is added, and the heat flux inside the member increases. Therefore, if the battery cell 210 becomes larger and the length of the CFRP member 230 provided on its surface becomes longer, the thickness of the CFRP member 230 (the area of the cross section perpendicular to the direction toward the thermal cooling mechanism 220) should be increased. It is preferable to make it thick. In addition, when considering the rigidity aspect of maintaining the shape while enduring the effects of vibrations during driving, etc. for automobile batteries, the thickness of the CFRP member 230 is more preferably 0.4 to 2.5 mm. is within the range of

Moreover, the CFRP member 230 can take any shape. For example, as described above, when the length in the direction of the thermal cooling mechanism 220 becomes longer, it is preferable to increase the cooling capacity as it approaches the thermal cooling mechanism 220. Therefore, it is possible to devise a shape such as a tapered structure in which the thickness increases closer to the thermal cooling mechanism 220.

Furthermore, in the power storage device structure 21 according to the present embodiment, the battery cell 210 has a depth in the y-axis direction shown in FIG. The entire surface of one side may be covered, or there may be an uncovered portion. In this embodiment, the coverage of the CFRP member 230 is preferably 40% or more, more preferably 50% or more.

When placing the CFRP member 230 according to this embodiment on the surface of the battery cell 210, a thermally conductive sheet (not shown) with excellent thermal conductivity is placed at the interface between the CFRP member 230 and the battery cell 210. You may. By arranging the CFRP member 230 on the surface of the battery cell 210 via such a thermally conductive sheet, it becomes possible to establish a thermal connection between the battery cell 210 and the CFRP member 230 more reliably. As such a thermally conductive sheet, for example, a high thermal conductivity sheet EX10000F7 manufactured by Dexerials Co., Ltd. can be mentioned.

When arranging the CFRP member 230 according to this embodiment on the surface of the battery cell 210, for example, as schematically shown in FIG. The CFRP member 230 may be thermally connected to the battery cell 210 using at least one of the greases 240. The thermal conductivity of the adhesive or grease 240 is more preferably 3.0 W/m·K or more. By using such an adhesive or grease 240, it becomes possible to thermally connect the CFRP member 230 to the battery cell 210 more reliably. Here, regarding the adhesive or grease 240 having thermal conductivity as described above, adhesives such as SX1008, SX1010, and RH96L manufactured by Cemedine Co., Ltd., and thermal conductive grease such as G-777 manufactured by Shin-Etsu Chemical Co., Ltd. can be exemplified. Furthermore, the adhesive or grease described above may be used in combination with various fillers and the like.

Note that when the device is mounted on a moving object such as a car, it is preferable to change the thickness of the adhesive or grease 240 as appropriate so that it can withstand vibrations. In this case, it is preferable that the thickness is not too thin; for example, when thermally conductive grease such as G-777 is used, it is preferable that the thickness is 0.25 mm or more for adhesion.

Further, when placing the CFRP member 230 according to the present embodiment on the surface of the battery cell 210, the CFRP member 230 is fixed at a location other than the battery cell 210 (not shown), and then the CFRP member 230 is It may also be in contact with the surface of the battery cell 210. Further, the CFRP member 230 according to this embodiment may be fixed on the surface of the battery cell 210 using screws or various fixing jigs (not shown).

On the other hand, when thermally connecting the CFRP member 230 according to this embodiment to the thermal cooling mechanism 220, the CFRP member 230 may be brought into direct contact with the thermal cooling mechanism 220. Further, as schematically shown in FIG. 16, a thermally conductive sheet 250 having excellent thermal conductivity may be disposed at the interface between the CFRP member 230 and the thermal cooling mechanism 220. By arranging the CFRP member 230 on the surface of the thermal cooling mechanism 220 via such a thermally conductive sheet 250, the thermal connection between the thermal cooler 220 and the CFRP member 230 is established more reliably, and the battery cell 210 can be cooled more reliably. As such a thermally conductive sheet 250, for example, a high thermal conductivity sheet EX10000F7 manufactured by Dexerials Co., Ltd. can be mentioned.

Alternatively, as schematically shown in FIG. 17A, a groove 221 may be provided on the surface of the thermal cooling mechanism 220, and the CFRP member 230 may be fitted into the groove 221. By realizing such fitting via the groove portion 221, it becomes possible to thermally connect the CFRP member 230 to the thermal cooling mechanism 220 more reliably.

Furthermore, in order to further improve thermal conductivity, as schematically shown in FIG. 17B, the end faces of the CFRP member 230 and the shapes of the grooves 221 are made oblique, thereby making it easier to connect the CFRP member 230 and the thermal cooling mechanism 220. The contact area may be increased. Furthermore, the contact area between the CFRP member 230 and the thermal cooling mechanism 220 may be increased by increasing the roughness of the end surface of the CFRP member 230 (roughening the roughness of the end surface). For example, by changing the shape so that the angle between the inclined surface and the end face of the thermal cooling mechanism 220 is 15° to 45°, the CFRP member 230 can be thermally connected to the thermal cooling mechanism 220 more reliably. It becomes possible. Note that such a method of thermal connection by increasing the contact area can be applied not only to the connection with the thermal cooling mechanism 220 but also to the connection with the battery cell 210.

Note that when connecting the CFRP member 230 to the battery cell 210 or the thermal cooling mechanism 220, the thermal connection methods shown in FIGS. 15 to 17B may be combined as appropriate.

In the electricity storage device structure 21 according to the present embodiment, as schematically shown in FIG. 18A, between a battery cell 210 provided with a CFRP member 230 and another battery cell 210 adjacent to the battery cell 210, A heat insulating member 260 may also be provided. By providing such a heat insulating member 260, it becomes possible to block heat transfer between adjacent battery cells 210, and it becomes possible to more reliably prevent thermal runaway of battery cells 210.

Such a heat insulating member 260 can be constructed using various materials as long as they can block heat transfer between battery cells 210. Examples of such materials include various resin materials such as polypropylene resin, polybutylene terephthalate resin, polycarbonate resin, epoxy resin, phenoxy resin, nylon resin, and polystyrene resin, nonwoven fabric, glass wool, rock wool, cellulose fiber, and urethane foam. , airgel, glass fiber reinforced resin, aramid fiber reinforced resin, etc.

Further, as schematically shown in FIG. 18B, the gap existing between adjacent battery cells 210 is filled using a CFRP member 230 provided on the surface of the battery cell 210 and a heat insulating member 260. You can do it like this. By realizing the filling structure as shown in FIG. 18B, it becomes possible to block heat transfer between adjacent battery cells 210 more reliably.

In the electricity storage device structure 21 according to the present embodiment, as schematically shown in FIG. The CFRP member 230 may include a PAN-based CFRP member 233 which is a CFRP containing PAN-based carbon reinforced fibers and is provided on the surface of the CFRP member 231 . In this case, for the pitch-based CFRP member 231, it is preferable that the orientation direction of the pitch-based carbon reinforced fibers be the direction toward the thermal cooling mechanism 220; It is more preferable to use a unidirectional material in the direction of . Further, the orientation direction of the PAN-based CFRP member 233 is not particularly defined, and the PAN-based CFRP member 233 may be constructed using a unidirectional material, or the PAN-based CFRP member 233 may be constructed using a cross material. You may. Furthermore, a CFRP member as described above may be constructed by laminating a plurality of CFRPs. In this way, by laminating the PAN-based CFRP member 233 on the pitch-based CFRP member 231, it is possible to improve the rigidity of the CFRP member 230, and to reduce the amount of more expensive pitch-based carbon reinforced fiber used. This makes it possible to reduce costs.

Further, a heat insulating member 260 as shown in FIGS. 18A and 18B may be provided on the surface of the CFRP member 230 as shown in FIG. 19.

Further, instead of the PAN-based CFRP member 233 shown in FIG. 19, a plastic member or a ceramic member may be arranged, or a plastic member or a ceramic member may be arranged on the surface of the PAN-based CFRP member 233. good.

Next, a method for measuring the thermal conductivity of the CFRP member 230 will be briefly described.
In this embodiment, the thermal conductivity of the carbon fiber reinforced plastic member 230 is measured by a straight fin temperature distribution fitting (SFTF) method.

Here, since the method for measuring the thermal conductivity of the CFRP member 230 using the SFTF method is the same as the measuring method shown in the first embodiment, detailed explanation will be omitted below. Regarding this measurement method, the description of "metal laminated CFRP member 110" in the first embodiment should be read as "CFRP member 230", and further, the measurement should be carried out assuming that there is no mention of the metal layer 113. Bye.

The electricity storage device structure 21 according to the present embodiment has been described in detail above with reference to FIGS. 13 to 19.

(About the manufacturing method of the electricity storage device structure)
The electricity storage device structure as explained above can be manufactured as follows. First, CFRP prepreg containing predetermined carbon reinforcing fibers and matrix resin is prepared, and a predetermined number of sheets are laminated to obtain a desired thickness. Thereafter, the obtained laminated prepreg is hot press molded or autograve molded to form a CFRP member.

The obtained CFRP member is placed on the surface of the battery cell using an adhesive or grease as necessary. A required number of integrated CFRP members and battery cells are thermally connected to a thermal cooling mechanism. Thereby, the electricity storage device structure according to this embodiment can be manufactured.

(About cooling method of power storage device structure)
A cooling method as an example of a heat dissipation method using the electricity storage device structure as described above will be briefly described below.
The method for cooling a power storage device structure according to the present embodiment is a cooling method for cooling a plurality of battery cells, and each of the plurality of battery cells, which are provided so that adjacent battery cells face each other, A CFRP member is thermally connected to the thermal cooling mechanism, and a CFRP member is provided on at least one surface of at least one of the plurality of battery cells facing another adjacent battery cell, and the CFRP member is thermally connected to the thermal cooling mechanism. Thermal connection to the cooling mechanism. This makes it possible to more efficiently cool down the temperature around the battery cell.

The power storage device structure and the heat dissipation method for the power storage device structure according to the second embodiment of the present invention have been described in detail above with reference to FIGS. 13 to 19.

Hereinafter, the power storage device structure and the heat dissipation method for the power storage device structure according to the present invention will be described while giving specific examples while showing Examples and Comparative Examples. Note that the examples shown below are only examples of the heat dissipation method for the power storage device structure and the power storage device structure according to the present invention, and the heat dissipation method for the power storage device structure and the power storage device structure according to the present invention are as follows. It is not limited to this example.

(Experiment example 1)
Experimental Example 1 shown below shows experimental results regarding the power storage device structure and the heat dissipation method of the power storage device structure shown in the first embodiment of the present invention.

[Automotive battery cells and modules]
For the battery cells, we used commercially available prismatic cells for automotive use (44 mm in length x 171 mm in width x 115 mm in height), and a module (190 mm in length x 400 mm in width x 130 mm in height) composed of 8 of the above cells. ) was created. The cell spacing was arbitrarily set and arranged. Note that the "cell spacing" here refers to the distance between the wall surfaces of adjacent cells.

[Charge/discharge test device]
EVT60V120A manufactured by Nippon Steel TexEngine Co., Ltd. was used for the charge/discharge test of the manufactured module.

[Cooling system]
The cooling device, which is an example of a heat dissipation mechanism, includes aluminum fins cut from a pure aluminum block (190 mm long x 400 mm wide x 40 mm high, with 10 fins 7 mm thick), or a self-made water cooling device (with long fins). A battery (190 mm wide x 400 mm wide x 40 mm high) was used, a battery module was placed on it, and the battery was charged and discharged.

[Production of CFRP prepreg]
An epoxy resin composition was prepared as a thermosetting resin serving as a matrix resin. The epoxy resin composition is applied to a reinforcing fiber base material made of pitch-based carbon fiber (UD material: carbon reinforced fiber XN80, XN90 manufactured by Nippon Graphite Fiber Co., Ltd.) or a reinforcing fiber base material made of PAN-based carbon fiber (UD material: M60J (manufactured by Toray Industries, Inc.) was impregnated to create an epoxy resin CFRP prepreg. All prepregs were impregnated with resin so that the VF of CFRP after heat molding was 60%.

[CFRP molding]
The produced CFRP prepregs were laminated to have the desired thickness and fiber orientation, placed in a vacuum bag together with a flat metal plate with a release paper in between, and molded in an autoclave. The CFRP molding conditions were as follows: 4 atm pressure was applied in an autoclave, and the temperature was held at 130° C. for 2 hours.

[Metal layer]
Copper foil and aluminum foil with a thickness of 0.02 mm were prepared as metal layers.

[Molding of metal layer laminated CFRP]
The produced CFRP prepreg and metal layer were laminated to have the desired thickness, fiber orientation and structure, and placed in a vacuum bag together with a flat metal plate with release paper in between, and heated in an autoclave at 130°C while applying 4 atm. It was held at ℃ for 2 hours and molded.

The obtained metal laminated CFRP member was attached to the cell using silicone grease (G-777, thermal conductivity 3.3 W/(m·K)) manufactured by Shin-Etsu Chemical. At this time, in the rectangular parallelepiped cell, CFRP was attached to the entire side surface of the cell (ie, at an area ratio of 100%). In addition, the attached CFRP was connected to the aluminum fins and water cooling device installed under the battery module using silicone grease (G-777, thermal conductivity 3.3 W/(m K)) manufactured by Shin-Etsu Chemical Co., Ltd. .

The detailed configuration of the fabricated power storage device structure is shown in Table 1 below, but in Comparative Example 3 in Table 1 below, although it is installed on an aluminum fin, there is no thermal conductor. is 5mm away from the aluminum fin and is not connected. Further, in Example 16 in Table 1 below, the heat conductor was not installed on any cooling mechanism, and the heat conductor protruded from the cell by 5 mm and was exposed to the air.

In addition, in Examples 1 to 18 and Comparative Examples 1 to 7 shown in Table 1 below, charging/discharging and temperature measurements were performed respectively in the form of a module in which a plurality of cells were connected (arranged side by side). In Example 19 and Comparative Examples 8 and 9, charging/discharging and temperature measurement were performed using a single cell.

◇Cooling performance evaluation A thermocouple was attached to any position on the cell surface using Kapton tape, and the temperature rise due to charging and discharging was measured. The charging and discharging conditions were set to a current of 3C, where the magnitude of the current that completely charges (or discharges) the capacity of the battery in 1 hour is defined as 1C, and charging and discharging were performed.

Under the above measurement conditions, the difference between the maximum temperature and the initial temperature during charging and discharging with no thermally conductive material attached is used as the reference temperature difference (Comparative Examples 1, 2, 3, 8), and the example and Calculate the percent difference between the maximum temperature and the initial temperature in the comparative example compared to the reference temperature difference (battery temperature reduction rate), and if the value is 1% or more, it is considered that there is a temperature reduction effect. . In other words, when the reference temperature difference is T ₀ °C and the temperature difference between the example or comparative example of interest and the initial temperature is T ₁ °C, ((T ₀ - T ₁ )/T ₀ ) The value obtained by multiplying by 100 is the battery temperature reduction rate. The case where the battery temperature reduction rate was 1% or more was rated A, and the case where the battery temperature reduction rate was less than 1% was rated B. A score of "A" was considered a pass.

◇Temperature evaluation when abnormal heat generation cells occur In a module with multiple stacked cells, temperature evaluation when abnormal heat generation cells occur is to measure the maximum temperature of adjacent cells, and when the heat conduction plate is a single CFRP. The evaluation was based on the percentage of temperature change compared to .

In this evaluation, first, the combinations of Examples and Comparative Examples shown in Table 2 were evaluated. Using a module in which the above eight cells are connected, when the two central cells generate heat at a constant heat value of 500 kW/h in an environment of 26°C, the maximum temperature of the adjacent cells at 2000 seconds after the start of heating. was measured and set as the temperature at that level. Naturally, it is preferable that the adjacent cell temperature is lower (that is, the value of the temperature change is smaller), and a score of 100% or less was given as "A", and a case where it was greater than 100% was given a score of "B". A score of "A" was considered a pass. The obtained results are summarized in Table 2.

As shown in Table 2 below, in the temperature evaluation when abnormal heating cells occur, in the thickness range shown in Table 2, when using CFRP or copper foil laminated CFRP, Al, heat insulating material, It became clear that the results were better than when using air. Based on this knowledge, the temperature evaluation at the time of abnormal heating cell occurrence was evaluated as "A" for each example shown in Table 1 based on the results shown in Table 2, and for each comparative example shown in Table 1. rated it as "B". Such measures will be described in detail below with reference to FIGS. 20A to 20C.

◇Evaluation of electromagnetic wave shielding properties of thermal conductive plates In frequency bands below 1 GHz, measurements are made in accordance with ASTM D 4935, and in frequency bands above that, electromagnetic wave transmission attenuation measuring device DPS10-02 manufactured by Keycom Co., Ltd. is used. The transmission attenuation of electromagnetic waves (i.e., shielding property) was measured using the following methods. When compared to CFRP alone (Comparative Example 2 below), when the transmitted electromagnetic waves are attenuated to 1/10 or less, it is considered to have an electromagnetic shielding effect and is considered A, and when it is not attenuated more than this, there is no effect. It was designated as B. A score of "A" was considered a pass.

Then, those that passed all of the cooling performance, temperature evaluation at the time of abnormal heating cell generation, and electromagnetic shielding evaluation will be given an overall evaluation result of "A", and those that have failed in any of them will be given an overall evaluation result of "A". The overall evaluation result was ``B''. The obtained results are summarized in Table 1.

In a module in which a plurality of cells are arranged side by side, typical results of measuring the maximum temperature of a cell adjacent to a cell that has abnormally generated heat are shown in FIGS. 20A to 20C. Among the examples and comparative examples shown in Table 2, this is because CFRP laminated with copper foil (copper foil laminated CFRP), CFRP, aluminum, heat insulating material, or air is inserted between the cells. In addition, these are the temperature measurement results when the cell spacing was 0.5 mm, 2.0 mm, and 5.0 mm, respectively. In FIGS. 20A to 20C, the horizontal axis represents time and the vertical axis represents temperature. Note that in FIGS. 20A and 20C, the temperature measurement results of the copper foil laminated CFRP and the temperature measurement results of the CFRP exhibited almost the same behavior, so the two curves appear to overlap in the drawings.

In each of FIGS. 20A to 20C, the temperature increases at each level over time, but the profiles are significantly different. First, since copper foil laminated CFRP, CFRP, and aluminum each have high thermal conductivity, the temperature of adjacent cells increases in a relatively short time. However, since heat is also conducted in the direction in which heat is released, as the elapsed time becomes longer, the effect of heat removal becomes greater and the temperature rise becomes slower. The reason why CFRP is able to suppress temperature increases better than aluminum is because there is anisotropy in heat conduction, so heat transfer to neighboring cells is smaller than with aluminum, and heat transfer in the direction of the heat dissipation mechanism. This is because it was equivalent to or better than aluminum. Furthermore, it can be seen that when a metal foil with good thermal conductivity such as copper foil is laminated on CFRP, its performance is further improved.

In contrast, insulation materials and air conduct little heat, so the initial temperature rise is slow. However, as time passes, the temperature of the abnormal heating cell becomes extremely high because the amount of heat transferred to the heat radiating mechanism and the amount of heat radiated into the air are small. As a result, the temperature of adjacent cells also rises rapidly, ultimately resulting in a higher temperature than when a heat-conducting material is attached.

In this way, in the laminated structure according to the present invention, not only the heat insulating material and the air but also the heat conductive materials such as aluminum and CFRP can be compared with heat conductors such as aluminum and CFRP. It can be seen that the temperature is well controlled. This holds true at least in the thickness range shown in FIGS. 20A to 20C, and it can be seen that the film essentially has such properties. From this, regardless of the configuration in Table 2, the CFRP laminated configuration in which the metal foil of the present invention is laminated has significant performance against thermally conductive materials such as CFRP and aluminum, and heat insulating materials. I know it's excellent.

As is clear from Tables 1 and 2 above, the electricity storage device structure corresponding to the example of the present invention passed the overall evaluation, while the electricity storage device structure corresponding to the comparative example of the invention It can be seen that any of the evaluations of performance, electromagnetic shielding property, or temperature evaluation at the time of occurrence of an abnormal heat generating cell failed.

(Experiment example 2)
Experimental Example 2 shown below shows experimental results regarding the power storage device structure and the heat dissipation method of the power storage device structure shown in the second embodiment of the present invention.

[Automotive battery cells and modules]
For the battery cells, we used commercially available prismatic cells for automotive use (44 mm in length x 171 mm in width x 115 mm in height), and a module (190 mm in length x 400 mm in width x 130 mm in height) composed of 8 of the above cells. ) was created. The gap between cells was set arbitrarily.

[Charge/discharge test equipment]
EVT60V120A manufactured by Nippon Steel TexEngine Co., Ltd. was used for the charge/discharge test of the manufactured module.

[Cooling system]
The cooling device that functions as a thermal cooling mechanism includes self-made aluminum fins (length 190 mm x width 400 mm x height 40 mm, fin thickness 7 mm x 10 pieces), or self-made water cooling device (length 190 mm x width 400 mm x height). A battery module was placed on top of the battery module, and the battery was charged and discharged. The battery cell cooling mechanism realized in this manner generally has a structure as illustrated in FIG. 14.

[Production of CFRP prepreg]
An epoxy resin composition was prepared as a thermosetting resin serving as a matrix resin. The epoxy resin composition is applied to a reinforcing fiber base material made of pitch-based carbon fiber (UD material: manufactured by Nippon Graphite Fiber Co., Ltd.) or a reinforcing fiber base material made of PAN-based carbon fiber (UD material: manufactured by Sakai Orvex Co., Ltd.). ) to create an epoxy resin CFRP prepreg. All prepregs were impregnated with resin so that the VF of CFRP after heat molding was 60%.

[CFRP molding]
The produced CFRP prepregs were laminated to have arbitrary thickness and fiber orientation, and molded in an autoclave. The CFRP molding conditions were as follows: 4 atm pressure was applied in an autoclave, and the temperature was held at 130° C. for 2 hours.

The obtained CFRP was attached to the cell using silicone grease (G-777, thermal conductivity 3.3 W/(m·K)) manufactured by Shin-Etsu Chemical. At this time, in the rectangular parallelepiped cell, CFRP was attached to the entire side surface of the cell (ie, at an area ratio of 100%). In addition, the attached CFRP was connected to the aluminum fins and water cooling device installed under the battery module using silicone grease (G-777, thermal conductivity 3.3 W/(m K)) manufactured by Shin-Etsu Chemical Co., Ltd. .

Note that after the thermally conductive material and the heat insulating member were arranged between the battery cells under the conditions shown in Table 3 below, gaps having the widths shown in Table 3 were made to exist. Further, when using a combination of CFRP using pitch-based carbon fiber and CFRP using PAN-based carbon fiber, the CFRP using pitch-based carbon fiber was positioned on the battery cell side.

Furthermore, in Examples 20 to 26 shown in Table 3 below, the case where a plurality of CFRPs are used in combination as a thermally conductive material and the case where a heat insulating member is used together are verified. In these examples, the numbers written in the columns of fiber type and heat insulating member indicate the ratio of the thickness of the members used. Furthermore, in the Examples and Comparative Examples shown in Table 4 below, the thickness of the grease was fixed at 1.0 mm and then verified.

◇Cooling performance evaluation A thermocouple was attached to any position on the cell surface using Kapton tape, and the temperature rise due to charging and discharging was measured. The charging and discharging conditions were set to a current of 3C, where the magnitude of the current that completely charges (or discharges) the capacity of the battery in 1 hour is defined as 1C, and charging and discharging were carried out.

Under the above measurement conditions, take the difference between the maximum temperature during charging and discharging and the initial temperature, calculate the ratio (unit: %) of the difference between the maximum temperature before pasting and the initial temperature, and subtract the value from 100. It was adopted as an evaluation value. If the value was 1.0 or more, it was determined that there was a temperature reduction effect and it was passed (score A), and if it was less than 1.0, it was determined that there was no temperature reduction effect and it was determined that it was not passed (score B).

◇Temperature evaluation when abnormal heat generation cells occur In a module where multiple cells are arranged side by side, when a cell generates abnormal heat generation, the maximum temperature of the adjacent cell is measured, and when the heat conduction plate is a single CFRP. The evaluation was based on the percentage of temperature change compared to

In this evaluation, first, the combinations of Examples and Comparative Examples shown in Table 4 were evaluated. Using a module in which the above eight cells are connected, when the two central cells generate heat at a constant heat value of 500 kW/h in an environment of 26°C, the maximum temperature of the adjacent cells at 2000 seconds after the start of heating. was measured and set as the temperature at that level. Naturally, it is preferable that the adjacent cell temperature is lower (that is, the value of the temperature change is smaller), and a score of 100% or less was given as "A", and a case where it was greater than 100% was given a score of "B". A score of "A" was considered a pass. The obtained results are summarized in Table 4.

As shown in Table 4 below, in the temperature evaluation when an abnormal heating cell occurs, in the thickness range shown in Table 4, the case using CFRP is better than the case using Al, insulation material, and air. It was found that the results were better than that of Based on this knowledge, the temperature evaluation at the time of abnormal heating cell occurrence was evaluated as "A" for each example shown in Table 3 based on the results shown in Table 4, and for each comparative example shown in Table 3. rated it as "B". Such measures will be explained in detail below with reference to FIGS. 21A to 21C.

On top of that, a case in which the cooling performance and the temperature evaluation at the time of occurrence of an abnormal heat generating cell were all passed was set as a comprehensive evaluation result A, and a case in which any of them failed was set as a comprehensive evaluation result B. The obtained results are summarized in Table 3.

In a module in which a plurality of cells are arranged side by side, typical results of measuring the maximum temperature of a cell adjacent to a cell that has abnormally generated heat are shown in FIGS. 21A to 21C. Among the examples and comparative examples shown in Table 4, CFRP, aluminum, heat insulating material, or air was inserted between the cells, and the cell spacing was 0.5 mm and 2.5 mm, respectively. These are the temperature measurement results at 0 mm and 5.0 mm. In FIGS. 21A to 21C, the horizontal axis represents time and the vertical axis represents temperature.

In each of FIGS. 21A to 21C, the temperature increases at each level as time passes, but the profiles are significantly different. First, since CFRP and aluminum each have high thermal conductivity, the temperature of adjacent cells increases in a relatively short time. However, since heat is also conducted in the direction in which heat is released, as the elapsed time becomes longer, the effect of heat removal becomes greater and the temperature rise becomes slower. The reason why CFRP is able to suppress the temperature rise better than aluminum is because there is anisotropy in heat conduction, so the heat transfer to neighboring cells is smaller than with aluminum, and the heat transfer towards the cooling device is smaller. This is because it was equivalent to or better than aluminum.

In contrast, insulation materials and air conduct little heat, so the initial temperature rise is slow. However, as time passes, the temperature of the abnormal heating cell becomes extremely high because the amount of heat transferred to the cooling mechanism and the amount of heat radiated into the air are small. As a result, the temperature of adjacent cells also rises rapidly, ultimately resulting in a higher temperature than when a heat-conducting material is attached.

In this way, in the laminated structure according to the present invention, not only the heat insulating material and the air but also the heat conductive materials such as aluminum and CFRP can be compared with heat conductors such as aluminum and CFRP. It can be seen that the temperature is well controlled. This holds true at least in the thickness range shown in FIGS. 21A to 21C, and it can be seen that the film essentially has such properties. From this, it can be seen that regardless of the configuration in Table 4, the CFRP laminated configuration of the present invention is significantly superior in performance to thermally conductive materials such as aluminum and heat insulating materials.

As is clear from Tables 3 and 4 above, the overall evaluation of the cooling structure of the battery cell corresponding to the example of the present invention is passed, while the cooling structure of the battery cell corresponding to the comparative example of the present invention is , cooling performance, and temperature evaluation at the time of occurrence of abnormal heating cells.

Although preferred embodiments of the present invention have been described above in detail with reference to the accompanying drawings, the present invention is not limited to such examples. It is clear that a person with ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea stated in the claims. It is understood that these also naturally fall within the technical scope of the present invention.

11, 21 Energy storage device structure 110 Metal laminated CFRP member 111, 230 CFRP member 113 Metal layer 120 Energy storage device 130, 240 Adhesive or grease 140 Heat dissipation mechanism 150 Refrigerant 160, 260 Heat insulating member 170 Stress relaxation member 180, 250 Heat conductive sheet 210 Battery Cell 220 Thermal Cooling Mechanism 221 Groove 231 Pitch-based CFRP Member 233 PAN-based CFRP Member

Claims (18)

multiple power storage devices;
a carbon fiber reinforced plastic member having oriented carbon reinforced fibers;
Equipped with
The carbon fiber reinforced plastic member is disposed on at least one surface of the plurality of power storage devices and is thermally connected to the power storage device,
At least one end of the carbon fiber-reinforced plastic member in the orientation direction of the carbon-reinforced fibers is such that the entire surface of the end is exposed to the atmosphere, or at least a portion of the end is exposed to a refrigerant or a heat dissipation mechanism. is in contact with at least one of
A plurality of the power storage devices are arranged to face each other, and the plurality of power storage devices are thermally connected to the heat radiation mechanism,
The carbon fiber reinforced plastic member is provided on at least one surface of at least one of the plurality of power storage devices that faces the other adjacent power storage device, and is thermally dissipated with respect to the heat dissipation mechanism. is connected to
When the carbon fiber reinforced plastic member is viewed from above, the end exposed in the atmosphere or the direction toward the refrigerant or heat radiation mechanism is defined as the 0° direction, and the direction perpendicular to the 0° direction is defined as the 90° direction. When the 0° direction component and the 90° direction component are respectively calculated with respect to the stretching direction of the carbon reinforced fibers included in the carbon fiber reinforced plastic member, The electricity storage device structure, wherein the 0° direction component in the stretching direction of the carbon reinforced fiber is 40% or more. The electricity storage device structure according to claim 1, wherein the carbon fiber reinforced plastic member is a metal laminated CFRP member in which a metal layer is provided on at least one surface of the carbon fiber reinforced plastic member. The power storage device structure according to claim 2, wherein the heat dissipation mechanism is an aluminum heat sink or a cooling mechanism that passes a coolant through a metal block. The power storage device structure according to claim 2 or 3, wherein a plurality of said metal laminated CFRP members on which said power storage devices are arranged exist and are connected in parallel to said heat dissipation mechanism. 5. The power storage device structure according to claim 2, wherein the power storage device is directly thermally connected to the carbon fiber reinforced plastic member of the metal laminated CFRP member. 5. The power storage device structure according to claim 2, wherein the power storage device is directly thermally connected to the metal layer of the metal laminated CFRP member. The electricity storage device structure according to any one of claims 2 to 6, wherein the metal layer has a thickness of 5.0 μm to 1.5 mm. The electricity storage device structure according to any one of claims 2 to 7, wherein the carbon fiber reinforced plastic member has a thickness of 0.1 to 5.0 mm. The electricity storage device structure according to any one of claims 2 to 8, wherein the metal layer is a metal foil or metal plate made of copper, aluminum, iron, stainless steel, or titanium. The electricity storage device structure according to any one of claims 1 to 9, wherein the carbon reinforced fiber is a pitch-based carbon reinforced fiber. The heat dissipation mechanism is provided with a groove,
The electricity storage device structure according to any one of claims 1 to 10 , wherein the carbon fiber reinforced plastic member is fitted into the groove. According to any one of claims 1 to 11, a heat insulating member is provided between the electricity storage device provided with the carbon fiber reinforced plastic member and another electricity storage device adjacent to the electricity storage device. The electricity storage device structure described. In the adjacent electricity storage devices, the carbon fiber reinforced plastic member is provided on the surface facing the other electricity storage device,
The carbon fiber reinforced plastic member having pitch-based carbon reinforced fibers is provided on the power storage device side, and the carbon fiber reinforced plastic member having carbon reinforced fibers other than pitch-based carbon reinforced fibers is provided on the other power storage device side. The electricity storage device structure according to any one of claims 1 to 12 , further comprising a carbon fiber reinforced plastic member. The heat dissipation mechanism is at least one of a cooling device that cools the heat transferred from the electricity storage device, or an electricity storage device case that houses the electricity storage device, according to any one of claims 1 to 13 . Energy storage device structure. The power storage device according to any one of claims 1 to 14 , wherein the carbon fiber reinforced plastic member has a thermal conductivity of 50 to 300 W/m·K in a direction perpendicular to the surface normal direction. Structure. Claims 1 to 15 , wherein the carbon fiber reinforced plastic member is thermally connected to another member via at least one of an adhesive or grease having a thermal conductivity of 0.1 W/m·K or more. The electricity storage device structure according to any one of the above. The electricity storage device structure according to any one of claims 1 to 16 , wherein the electricity storage device is a battery cell. A carbon fiber-reinforced plastic member having oriented carbon-reinforced fibers is arranged on at least one surface of the plurality of power storage devices, and the carbon fiber-reinforced plastic member and the power storage device are thermally connected;
At least one end of the carbon fiber-reinforced plastic member in the direction of orientation of the carbon-reinforced fibers is exposed entirely to the atmosphere, or at least a portion of the end is exposed to a refrigerant or a heat dissipation mechanism. contact with at least one of
A plurality of the power storage devices are arranged to face each other, and the plurality of power storage devices are thermally connected to the heat dissipation mechanism,
The carbon fiber reinforced plastic member is provided on at least one surface of at least one of the plurality of power storage devices facing the other adjacent power storage device, and the carbon fiber reinforced plastic member is provided thermally with respect to the heat dissipation mechanism. connect,
When the carbon fiber reinforced plastic member is viewed from above, the end exposed in the atmosphere or the direction toward the refrigerant or heat radiation mechanism is defined as the 0° direction, and the direction perpendicular to the 0° direction is defined as the 90° direction. When the 0° direction component and the 90° direction component are respectively calculated with respect to the stretching direction of the carbon reinforced fibers included in the carbon fiber reinforced plastic member, A heat dissipation method for a power storage device structure, wherein the 0° direction component in the stretching direction of the carbon reinforced fiber is 40% or more.

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