Heater unit, heating device, temperature control system, and electric vehicle

Abstract

A heater unit according to the present disclosure is mounted on a heating device for an electric vehicle, and comprises: a ceramic heater provided with a heating element; a heat dissipation body including a first surface on a side facing the ceramic heater and a second surface which is different from the first surface and which has a heat dissipation surface; and a heat conduction member disposed between the first surface of the heat dissipation body and the ceramic heater and in contact with both the ceramic heater and the first surface. The heat conduction member has at least one of elasticity, ductility, and malleability higher than that of the ceramic heater and the heat dissipation body.

Description

Heater unit, heating device, temperature control system and electric vehicle

[0001] The present disclosure relates to a heater unit, a heating device, a temperature control system, and an electric vehicle.

[0002] Recently, there has been a shift from conventional engine vehicles to electric vehicles, hybrid vehicles, plug-in hybrid vehicles, and other electrically powered vehicles.

[0003] When electric vehicles are used in cold climates, the energy efficiency of the electrolyte contained in the drive battery may decrease, resulting in a shorter driving distance. For this reason, electric vehicles are sometimes equipped with a heating device to heat the electrolyte contained in the drive battery.

[0004] Japanese Patent Application Laid-Open No. 2020-136036

[0005] A heater unit according to one aspect of the present disclosure is a heater unit mounted on a heating device for an electric vehicle, and includes a ceramic heater having a heating element, a heat sink including a first surface facing the ceramic heater and a second surface having a heat dissipation surface different from the first surface, and a heat conduction member arranged between the first surface of the heat sink and the ceramic heater, and in contact with both the ceramic heater and the first surface, wherein the heat conduction member has at least one of higher elasticity, ductility, and malleability than the ceramic heater and the heat sink.

[0006] FIG. 1 is a schematic perspective view of a heater unit according to a first embodiment. FIG. 2 is a schematic front view of a heating element and a ceramic heater according to the first embodiment. FIG. 3 is a schematic cross-sectional view of a heater unit according to the first embodiment. FIG. 4 is a schematic cross-sectional view of a heater unit according to the first embodiment. FIG. 5 is a schematic cross-sectional view of a heater unit according to a second embodiment. FIG. 6 is a schematic cross-sectional view of a heater unit according to the second embodiment. FIG. 7 is a schematic side view of a heat dissipator according to a third embodiment. FIG. 8 is a schematic plan view of a heat dissipator according to the third embodiment. FIG. 9 is a schematic cross-sectional view of a heating device according to a fourth embodiment. FIG. 10 is a schematic perspective view of a heating device according to a fifth embodiment. FIG. 11 is a schematic cross-sectional view of a heating device according to the fifth embodiment. FIG. 12 is a schematic perspective view of a heating device according to a sixth embodiment. FIG. 13 is a schematic perspective view of a heating device according to a seventh embodiment.

[0007] Hereinafter, a heater unit, a heating device, a temperature control system, and an electric vehicle according to the present disclosure (hereinafter referred to as "embodiments") will be described in detail with reference to the drawings. Note that the present disclosure is not limited to these embodiments. Furthermore, the embodiments can be appropriately combined as long as the processing content is not contradictory. Furthermore, the same components in the following embodiments will be assigned the same reference numerals, and duplicated explanations will be omitted.

[0008] Electric vehicles are often equipped with a temperature control system to adjust the performance of the electric vehicle battery. Recently, with the increasing demand for higher output and smaller size of electric vehicle batteries, there is a demand for higher performance and smaller size of temperature control systems. To meet these demands, there is a need for a heater unit that is high-output, compact, and highly reliable.

[0009] First Embodiment The configuration of a heater unit according to the first embodiment will be described with reference to FIGS. 1 to 4. FIG. 1 is a schematic perspective view of the heater unit according to the first embodiment. FIG. 2 is a schematic front view of the heating element and ceramic heater according to the first embodiment. FIGS. 3 and 4 are schematic cross-sectional views of the heater unit according to the first embodiment. Note that FIG. 3 shows a cross section taken along the line III-III in FIG. 4, and FIG. 4 shows a cross section taken along the line IV-IV in FIG. 3. Also, the heating element 2, terminals 71 and 72, and wiring members 73 and 74 are not shown in FIGS. 3 and 4.

[0010] 1 to 4 is a heater unit used in a heating device that heats a drive battery of an electric vehicle. The configuration of the heating device including the heater unit 1 will be described later with reference to FIG.

[0011] As shown in FIGS. 1 and 2, the heater unit 1 according to the first embodiment includes a ceramic heater 3 having a heating element 2, a heat sink 4, and a heat conduction member 5.

[0012] The heating element 2 is made of, for example, a metal material. For example, tungsten can be used as the metal for the heating element 2. The heating element 2 generates heat (Joule heat) when electricity flows through it.

[0013] 2, the heating element 2 is embedded inside the ceramic heater 3. The heating element 2 may have a linear pattern having a plurality of folded portions 21. Note that the pattern formed by the heating element 2 is not limited to the example shown in FIG.

[0014] One end and the other end of the heating element 2 are located on the first end surface 31 (here, the upper end surface) side of the ceramic heater 3. One end of the heating element 2 is connected to a wiring member 73 via a terminal 71 provided on the first end surface 31, and the other end of the heating element 2 is connected to a wiring member 74 via a terminal 72 provided on the first end surface 31. The heating element 2 is connected to an external power source via these terminals 71, 72 and wiring members 73, 74.

[0015] The ceramic heater 3 has, for example, a rectangular parallelepiped shape. The material used for the ceramic heater 3 is, for example, alumina (Al ２ O ３ Alumina has a higher thermal conductivity than other ceramics, and is also highly heat-resistant and corrosion-resistant, making it suitable for use in heating devices for electric vehicle drive batteries.

[0016] The ceramic heater 3 may contain components other than alumina, which is the main component. In this disclosure, the term "main component" refers to a component that accounts for 80% by mass or more of the total 100% by mass of the components that make up the ceramic. Each component contained in the ceramic is identified using an X-ray diffraction device using CuKα radiation, and the content of each component can be determined using, for example, an ICP (Inductively Coupled Plasma) emission spectrometer or an X-ray fluorescence analyzer.

[0017] The main component of the ceramic material used in the ceramic heater 3 does not necessarily have to be alumina. For example, the ceramic heater 3 may contain other ceramic materials such as silicon nitride as the main component. A ceramic heater containing a ceramic material as the main component has relatively high hardness and rigidity, and has relatively high resistance to external vibrations and impacts, as well as pressure from other members.

[0018] The heat sink 4 is, for example, a rectangular parallelepiped metal member. Aluminum is an example of a metal material used for the heat sink 4. Aluminum is relatively low cost, has high thermal conductivity, and is lightweight compared to other metals, making it suitable for use in a heating device for an electric vehicle drive battery.

[0019] The metal material used for the heat sink 4 does not necessarily have to be aluminum. For example, the metal material used for the heat sink 4 may be SUS (stainless steel), copper, brass, or the like.

[0020] The heat sink 4 has a first surface 45A facing the ceramic heater 3 and a heat dissipation surface 45B different from the first surface 45A. Specifically, the heat sink 4 has a housing 45, a portion of the inner surface of which constitutes the first surface 45A, and the outer surface of the heat sink 4 constitutes the heat dissipation surface 45B. The housing 45 houses the ceramic heater 3 and a thermally conductive member 5, which will be described later. Specifically, the housing 45 is a bottomed space having an opening 46 in a first end surface 41 (here, the upper end surface) of the heat sink 4. That is, the heat sink 4 has a second end surface 42 located opposite the first end surface 41, and the housing 45 is closed on the side opposite the opening 46 by the second end surface 42 of the heat sink 4. The heat sink 4 transfers the thermal energy received from the ceramic heater 3 in the region including the first surface 45A via the heat sink surface 45B to the heat medium or the like in contact with this heat sink surface 45B. The ceramic heater 3 itself can heat up to a fairly high temperature in a short time, but the provision of the heat sink 4 can slow down the speed of this temperature rise. For example, if the heat medium comes into direct contact with the surface of the ceramic heater 3, the heat medium will undergo a rapid state change, making it impossible to maintain the long-term reliability of the heater unit 1. Even in this case, the provision of the heat sink 4 can reduce the deterioration in reliability due to this state change.

[0021] In the first embodiment, the heat sink 4 is manufactured by cutting a single metal block. In this case, the risk of the heat transfer medium or other foreign matter entering the housing portion 45 from a location other than the opening 46 of the heat sink 4 is reduced, and deterioration of the heater unit 1 due to the intrusion of foreign matter can be reduced.

[0022] 1 and 3 , a portion of the ceramic heater 3 including the first end surface 31 protrudes from the opening 46 of the heat sink 4 to the outside of the housing portion 45. The heating element 2 is located in the portion of the ceramic heater 3 that protrudes to the outside of the housing portion 45. Specifically, at least one of the multiple folded portions 21 (see FIG. 2 ) of the heating element 2 protrudes from the opening 46 of the heat sink 4 to the outside of the housing portion 45. In other words, a portion of the pattern of the heating element 2 protrudes from the opening 46 of the heat sink 4 to the outside of the housing portion 45.

[0023] The portion of the ceramic heater 3 that protrudes from the opening 46 of the heat radiator 4 to the outside of the housing 45 is located above the liquid level of the heat medium stored in the container of the heating device when the heater unit 1 is mounted on the heating device (see FIG. 8 described later), so there is little chance of the heat medium adhering to it. Therefore, by exposing this portion from the heat radiator 4, the portion of the ceramic heater 3 that is located below the liquid level of the heat medium is protected by the heat radiator 4, while the weight of the heater unit 1 can be reduced compared to when the heat radiator 4 is large enough to cover the entire heating element 2.

[0024] Furthermore, since the pattern of the heating element 2 is positioned in the ceramic heater 3 from the opening 46 of the heat radiator 4 to the portion protruding outside the housing portion 45, the air inside the container of the heating device can be heated directly without going through the heat radiator 4. This allows the air inside the container of the heating device to be heated efficiently, thereby efficiently heating the entire container, further improving the heating efficiency of the heat medium.

[0025] The heat conduction member 5 is disposed between the first surface 45A of the heat sink 4 and the ceramic heater 3, and is in contact with both the ceramic heater 3 and the first surface 45A. The heat conduction member 5 has at least one of higher elasticity, ductility, and malleability than the ceramic heater 3 and the heat sink 4. When the heat sink 4 is made of metal, as in this embodiment, local stress caused by differences in the thermal expansion between the heat sink 4 and the heater may damage the heater or the heat sink 4. The heat conduction member 5 of this embodiment has high properties of at least one of elasticity, ductility, and malleability, and can deform by stretching or expanding, thereby alleviating stress caused by the difference in thermal expansion and improving the reliability of the heater unit 1. Furthermore, the heat conduction member 5 deforms to fill minute gaps between the surface of the ceramic heater 3, which has high hardness, and the heat sink 4, thereby relatively increasing the efficiency and speed of heat conduction from the ceramic heater 3 to the heat sink 4. By providing such a heat conducting member 5, multiple problems that arise when using a ceramic heater that is both hard and has a high temperature rise rate are simultaneously solved, and a heater unit with high performance and reliability is realized.

[0026] For the reasons described above, the heater unit 1 according to the first embodiment is suitable for use as a heating device for an electric vehicle drive battery.

[0027] An example of a material used for the thermally conductive member 5 is graphite. Graphite serves as a buffer material to cushion the impact that the ceramic heater 3 receives from the heat sink 4, while efficiently transferring heat generated by the heating element 2 to the heat sink 4. Alternatively, aluminum foil may be used for the thermally conductive member. Because aluminum has ductility and malleability, when the heater unit thermally expands due to the heat from the heating element 2, it serves as a buffer material and efficiently transfers the heat from the heating element 2 to the heat sink 4. In this case, the aluminum foil may be laminated. By laminating the aluminum foil, the compressive force of the thermally conductive member during thermal expansion of the heater unit is dispersed, thereby increasing durability. Alternatively, metallization may be used for the thermally conductive member 5. Examples of metallization include tungsten, molybdenum manganese, and the like.

[0028] The material used for the heat conduction member 5 may be in a sheet form. For example, the material used for the heat conduction member 5 may be a graphite sheet. Using a sheet-like heat conduction member 5 makes it easy to position the heat conduction member 5 without any gaps between the ceramic heater 3 and the heat sink 4. Specifically, as shown in FIGS. 3 and 4 , the heat conduction member 5 covers the entire surface of the ceramic heater 3 and the entire surface of the heat sink 4 without any gaps in the region where the ceramic heater 3 and the heat sink 4 face each other (i.e., inside the housing portion 45). "Coversing without any gaps" means that there is no region where the ceramic heater 3 and the heat sink 4 directly face each other without the heat conduction member 5 in between.

[0029] With this configuration, compared to when a gap exists in part of the region where the ceramic heater 3 and the heat sink 4 face each other, local temperature differences are less likely to occur in the ceramic heater 3, which more effectively reduces cracking of the ceramic heater 3 due to thermal shock caused by local temperature differences. In other words, the durability of the ceramic heater 3 can be further improved. Also, compared to when a gap exists in part of the region where the ceramic heater 3 and the heat sink 4 face each other, heat can be transferred more efficiently from the heating element 2 to the heat sink 4.

[0030] The sheet-like heat conduction member 5 does not necessarily have to be a graphite sheet. The sheet-like heat conduction member 5 may be, for example, a silicon sheet or a resin sheet, other than a graphite sheet. The heat conduction member 5 does not necessarily have to be in sheet form, and may be in paste form. Examples of paste-like heat conduction members 5 include boron nitride and silver. Other materials used for the heat conduction member 5 may be, for example, an oil compound. An adhesive may be positioned between the heat conduction member 5 and the heat sink 4. Although not shown, the heat conduction member 5 may be positioned only at the locations on the surface of the ceramic heater 3 where the heating element 2 is present, or only at the locations where the heating element 2 is not present.

[0031] 1 and 3, the heat conduction member 5 may protrude from the opening 46 of the heat sink 4 to the outside of the housing portion 45. With this configuration, the risk of deterioration of the heater unit 1 due to the heat medium or other foreign matter entering the inside of the housing portion 45 can be reduced.

[0032] Second Embodiment Figures 5 and 6 are schematic cross-sectional views of a heater unit 1 according to a second embodiment. Note that Figure 5 shows a cross section taken along the arrows V-V in Figure 6, and Figure 6 shows a cross section taken along the arrows VI-VI in Figure 5. Also, Figures 5 and 6 omit illustration of the heating element 2, terminals 71 and 72, and wiring members 73 and 74.

[0033] 5 and 6 , the heater unit 1 according to the second embodiment may further include a sealing portion 6. The material used for the sealing portion 6 may be, for example, glass or resin. The sealing portion 6 is located on the first end surface 41 of the heat sink 4, spanning the first end surface 41, the thermally conductive member 5, and the ceramic heater 3. Furthermore, as shown in FIG. 6 , the sealing portion 6 is located circumferentially so as to surround the ceramic heater 3 in a plan view.

[0034] In this way, in the heater unit 1 according to the second embodiment, the opening 46 of the housing portion 45 is sealed using the sealing portion 6. With this configuration, it is possible to further reduce the risk of deterioration of the heater unit 1 due to the heat medium or other foreign matter entering the inside of the housing portion 45.

[0035] Third Embodiment In the first embodiment described above, an example in which the heat sink 4 is made of a single metal member has been described. In the third embodiment, an example in which the heat sink 4 is made of a plurality of metal members will be described. Fig. 7 is a schematic side view of the heat sink 4 according to the third embodiment. Fig. 8 is a schematic plan view of the heat sink 4 according to the third embodiment.

[0036] 7 and 8 , the heat sink 4 according to the third embodiment is made up of two metal members, a first member 401 and a second member 402. The heat sink 4 is formed by combining the first member 401 and the second member 402. Specifically, a recess 401a corresponding to part of the accommodation portion 45 is formed in the first member 401, and a recess 402a corresponding to part of the accommodation portion 45 is also formed in the second member 402. By combining the first member 401 and the second member 402, the heat sink 4 having the accommodation portion 45 is formed.

[0037] The heat sink 4 according to the third embodiment has a joint 403 at the contact point between the first member 401 and the second member 402. The joint 403 is a location where brazing or welding has been performed. The joint 403 may be, for example, a weld mark. The joint 403 covers the entire periphery of the contact position between the first member 401 and the second member 402 on the surface of the heat sink 4.

[0038] In this way, in the third embodiment, the first member 401 and the second member constituting the heat dissipation body 4 are joined by brazing or welding. This configuration reduces the risk of the heat medium or other foreign matter entering the accommodation portion 45 through the gap between the first member 401 and the second member 402, thereby reducing deterioration of the heater unit 1 due to the intrusion of foreign matter.

[0039] Here, an example has been described in which the heat sink 4 is made up of two metal members (the first member 401 and the second member 402), but the heat sink 4 may be made up of three or more metal members.

[0040] Fourth Embodiment In a fourth embodiment, a configuration example of a heating device equipped with the heater unit 1 described above will be described with reference to Fig. 9. Fig. 9 is a schematic cross-sectional view of the heating device according to the fourth embodiment. Note that terminals 71, 72 and wiring members 73, 74 are not shown in Fig. 9.

[0041] 9 is a heating device for heating a drive battery of an electric vehicle, and is disposed inside the electric vehicle near the drive battery. The heating device 100 uses a heater unit 1 to heat a heat medium 102 (an example of a thermal solvent), and uses the heated heat medium 102 to heat a drive battery 200.

[0042] 9 , the heating device 100 includes a heater unit 1, a circulation mechanism 110 that circulates a heat medium 102 heated by the heater unit 1, a container 101 that is a container body that stores the heat medium 102 during circulation, and an inner lid 103. The circulation mechanism 110 also includes a flow path 104, a valve 105, and a pump 106.

[0043] The container 101 is made of, for example, a resin material. However, the container 101 may be made of a metal material. The container 101 may also be made of a material other than a resin material or a metal material.

[0044] The container 101 contains a heater unit 1, a heat medium 102, and an inner lid 103. Although only one heater unit 1 is shown in Fig. 9, a plurality of heater units 1 may be contained in the container 101. In this case, the plurality of heater units 1 may be arranged side by side, for example, in the depth direction (X-axis direction) of the paper surface in Fig. 9.

[0045] The container 101 has an inlet 111 and an outlet 112 for the heat transfer medium 102. One end of a flow path 104 (described later) is connected to the inlet 111, and the other end of the flow path 104 is connected to the outlet 112. The container 101 and the flow path 104 form a circulation path for the heat transfer medium 102.

[0046] The heat medium 102 is, for example, water. However, the heat medium 102 is not limited to this, and may be a liquid other than water, such as oil. In the heating device 100, at least a portion of the heater unit 1 is housed in a container 101, and at least a portion of the heat dissipation surface 45B is in contact with the heat medium 102. The heating device 100 including the heater unit 1 of the above-described embodiment has a relatively high rate of temperature rise of the heat medium 102 and is also highly reliable.

[0047] The heater unit 1 is housed in a container 101 with the first end surface 31 of the ceramic heater 3 facing upward. The water level of the heat medium 102 in the container 101 is set to be at the same level as or lower than the first end surface 41 of the heat radiator 4. In other words, the water level of the heat medium 102 is set so as not to be higher than the portion of the ceramic heater 3 exposed from the heat radiator 4. This reduces adhesion of the heat medium 102 to the ceramic heater 3 exposed from the heat radiator 4.

[0048] The inner lid 103 is placed on the first end surface 41 of the heat dissipation body 4. The inner lid 103 has an opening for inserting the ceramic heater 3, and the ceramic heater 3 protrudes above the inner lid 103 through the opening. By providing the inner lid 103 inside the container 101 in this manner, it is possible to further effectively reduce adhesion of the heat medium 102 to the ceramic heater 3 exposed from the heat dissipation body 4.

[0049] The heating element 2 is located above the liquid level of the heat medium 102 inside the container 101. Specifically, at least one of the multiple folded portions 21 of the heating element 2 is located above the liquid level of the heat medium 102 inside the container 101. In other words, a part of the pattern of the heating element 2 is located above the liquid level of the heat medium 102 inside the container 101. With this configuration, heating efficiency can be improved compared to when the heating element 2 is not located above the liquid level of the heat medium 102.

[0050] The flow path 104 constitutes part of the circulation path of the heat medium 102. The flow path 104 extends so that at least a portion thereof is in contact with or close to the driving battery 200. In the example shown in FIG. 9 , a portion of the flow path 104 spirally surrounds the driving battery 200, but the flow path 104 does not necessarily have to surround the driving battery 200. A valve 105 and a pump 106 are provided in the flow path 104. The valve 105 opens and closes the flow path 104. The valve 105 can also switch to a flow path 94 on the heat pump unit 90 side, which will be described later. The pump 106 generates a flow of the heat medium 102 from the inlet 111 to the outlet 112 by the action of pressure. Note that the arrangement of the heating device 100, the valve 105, and the pump 106 in the circulation path of the heat medium 102 is not limited to the example shown in FIG. 9 .

[0051] The heating device 100 is configured as described above, and is able to heat the driving battery 200 by circulating the heat medium 102 heated by the heater unit 1 near the driving battery 200. The heating device 100 equipped with the heater unit 1 has a high heating speed due to the ceramic heater 3, high heating energy efficiency, and is also highly reliable. An electric vehicle equipped with the heater unit 1 and the heating device 100 can heat the heated portion in a relatively short time when it is necessary to heat the battery, for example, at startup.

[0052] The present invention also provides a temperature control system 1000 for an electric vehicle, the temperature control system including the heater unit 1 described above, at least a heat medium 102 heated by the heater unit 1, a heat pump unit 90 capable of adjusting the temperature of the thermal solvent, a circulation mechanism 110 that circulates the heat medium 102, and a control unit 99, wherein the control unit 99 controls the operation of at least the circulation mechanism 110 to select a flow path for the heat medium 102 to flow to at least one of the heater unit 1 or the heat pump unit 90. The temperature control system 1000 of this embodiment includes a temperature sensor (not shown) that can detect the temperature of the battery, and the control unit 99 causes the heat medium 102 to flow through the heater unit 1 when the temperature detected by the temperature sensor is below a specific temperature, and causes the heat medium 102 to flow through the heat pump unit 90 when the detected temperature is equal to or higher than the specific temperature.

[0053] The heat pump unit 90 is a typical heat pump unit that combines heating and cooling mechanisms. The heat pump unit 90 has advantages such as relatively high thermal efficiency, relatively low energy running costs when used for a relatively long period of time, and the ability to regulate the temperature even if the battery overheats due to long-term operation, but the heating rate itself is relatively slow. For example, when starting an electric vehicle, the heat pump unit 90 alone may take a long time to heat the battery to a temperature at which sufficient performance can be achieved, which may place a heavy load on the battery and affect the performance of the electric vehicle. In the temperature control system 1000 of this embodiment, by selecting a flow path using the control unit 99, for example, when starting an electric vehicle, the heater unit 1 including the ceramic heater 3 can rapidly heat the battery to a temperature at which sufficient performance can be achieved in a short period of time, and then the heat pump unit 90 can control the battery temperature to an appropriate temperature with high energy efficiency. To improve the heat balance, the heater unit 1 is preferably placed near the heat pump unit 90. However, the heat pump unit 90 includes a compressor, and vibrations from this compressor are transmitted to the periphery of the heat pump unit 90. For example, with a typical PTC heater, the heater device itself has low hardness and is relatively susceptible to vibrations. Therefore, it is difficult to place it near the heat pump unit 90 while maintaining a good heat balance in terms of durability. The heater unit 1 includes a highly durable ceramic heater 3, and furthermore, the thermal conductive member 5, which has high elasticity, ductility, and / or malleability, absorbs shocks and pressures caused by vibrations. Therefore, the temperature control system 1000 can heat the heat medium 102 quickly, has high thermal efficiency, and is sufficiently durable.

[0054] Fifth Embodiment In the fifth embodiment, an example will be described in which the heat sink 4 of the third embodiment described above has a different shape. Fig. 10 is a schematic perspective view of a heating device according to the fifth embodiment. Fig. 11 is a schematic cross-sectional view of the heating device according to the fifth embodiment.

[0055] As shown in FIGS. 10 and 11, the heat sink 4 according to the fifth embodiment is made up of at least two members, and may have a recess in the housing portion.

[0056] Furthermore, the heater unit and the heat conducting member 5 are located in a recess in the heat sink 4, and the heat sink 4 may be pressed by a leaf spring 61. Fixing the heater unit and the heat conducting member 5 with the leaf spring 61 allows the leaf spring 61 to expand and contract in accordance with thermal expansion, thereby alleviating the concentration of thermal stress caused by the thermal expansion of the heater unit.

[0057] Furthermore, by providing the recess, an area where the heater unit and the heat conducting member 5 can thermally expand can be provided, thereby alleviating the concentration of thermal stress due to thermal expansion.

[0058] Sixth Embodiment In the sixth embodiment, an example in which the heat sink 4 of the above-described embodiments is used is described. FIG. 12 is a schematic exploded perspective view of a heating device according to the sixth embodiment. Note that in FIG. 12, the components are shown separated vertically to facilitate understanding of the structure. However, in reality, the components are in contact with each other vertically. As shown in FIG. 12, in the sixth embodiment, the heat sink 4 includes a conduit 4α, and the heat sink surface 45B is disposed on at least a portion of the inner surface of the conduit 4α. At this time, the heat medium flows in the direction indicated by the arrows, as shown in FIG. 12. Although not shown in FIG. 12, a thermally conductive member 5 having at least one of higher elasticity, ductility, and malleability than the ceramic heater 3 and the heat sink 4 is provided in the gap between the ceramic heater 3 and the heat sink 4, thereby achieving the same effects as the other embodiments. In the heater unit of the sixth embodiment, as shown in FIG. 12, multiple ceramic heaters 3 are arranged along the axial direction of the conduit 4α. Furthermore, multiple structures each including a ceramic heater 3, a heat sink 4, and a heat conductive member 5 are stacked. Each ceramic heater 3 is individually equipped with an electrode, and its output can be controlled via the electrode. The sixth embodiment has multiple pipes 4α (i.e., multiple flow paths for the heat medium), and multiple ceramic heaters 3 are arranged along the axial direction of each pipe 4α (i.e., along the direction of the heat medium flow). The heater unit of the sixth embodiment can finely and accurately adjust the degree of heating of the heat medium by individually controlling the main power of these multiple ceramic heaters 3. The heater unit of the sixth embodiment may be used as the heater unit in the heating device 100 shown in FIG. 9. The present invention also provides a heating device and a temperature control system using the heater unit of the sixth embodiment.

[0059] Seventh Embodiment In the seventh embodiment, an example will be described in which the heat sink 4 described above has a different shape. Fig. 13 is a schematic exploded perspective view of a heater unit according to the seventh embodiment. Note that in Fig. 7, the components are shown disassembled and separated to make the structure easier to understand, but in reality, the components are assembled in contact with each other.

[0060] As shown in Fig. 13, the seventh embodiment includes a housing having an opening, a heat sink 4 located near the opening, and a heat sink surface 45B covering the opening, and at least one surface inside the housing and the heat sink surface 45B form a flow path. In the seventh embodiment, the heat medium passing through this flow path is heated via the heat sink surface 45B. Although not shown in Fig. 13, the seventh embodiment also includes a thermally conductive member 5 in the gap between the ceramic heater 3 and the heat sink 4, the thermal conductive member 5 having at least one of elasticity, ductility, and malleability higher than the ceramic heater 3 and the heat sink 4, and has the same effects as the other embodiments.

[0061] In the seventh embodiment, the flow path allows the heat medium to flow along the heat dissipation surface 45B for a relatively long time. The heat dissipation surface 45B may have grooves (not shown), which may constitute at least a portion of the flow path. This can relatively increase the superheating efficiency of the flow path itself. Furthermore, the inner surface of the flow path may have fine irregularities, for example, an inner surface of the flow path having a wavy cross section when viewed from above. Providing such irregularities can also generate turbulence in the heat medium flowing through the flow path, further improving heating efficiency. Furthermore, when the flow path formed by the heat dissipation surface 45B has irregularities, the contact area with the heat medium can be increased, further improving heating efficiency. Furthermore, fins may be attached to the heat dissipation body 4 to form multiple passages within the flow path. This can also generate turbulence in the heat medium flowing through the flow path, further improving heating efficiency. Furthermore, the extension direction of the fins may be perpendicular to the heat dissipation body 4 or may be wavy.

[0062] Furthermore, the heater unit of the seventh embodiment has multiple ceramic heaters 3 arranged on one main surface of the heating element, resulting in a large heat output. In the seventh embodiment, the output of the multiple ceramic heaters 3 can be individually controlled, allowing for precise and accurate adjustment of the heating level of the heat medium flowing along the flow path. As shown in FIG. 13 , the heater unit 1 may be sandwiched between another housing that forms part of the flow path. It is preferable that the gap between the other housing and the ceramic heater 3 also be provided with components having a structure similar to the heat sink 4 and thermally conductive member 5. It goes without saying that the heater unit of the seventh embodiment may be used as the heater unit in the heating device 100 shown in FIG. 9 . The present invention also provides a heating device and a temperature control system using the heater unit of the seventh embodiment.

[0063] The present invention also provides an electric vehicle equipped with the heater unit, heating device, and temperature control system of each of the above-described embodiments. The electric vehicle of the present invention quickly heats up to a temperature at which the battery, for example, performs adequately upon startup, allowing the vehicle to reach a suitable operating state in a short time without increasing the load on the battery. In other words, the vehicle is excellent in both durability and performance. The heated object is not limited to the battery, and similar effects can be achieved for any part that requires heating in a short time. The electric vehicle of the present invention exhibits excellent effects in terms of performance, durability, and safety, particularly in cold regions.

[0064] The disclosed embodiments should be considered in all respects as illustrative and not restrictive. Indeed, the above-described embodiments may be embodied in various forms. Furthermore, the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

[0065] REFERENCE SIGNS LIST 1 heater unit 2 heating element 3 ceramic heater 4 heat dissipation element 5 heat conduction member 6 sealing portion 31 first end surface 41 first end surface 42 second end surface 45 accommodation portion 46 opening 90 heat pump unit 99 control portion 100 heating device 101 container 102 heat medium 103 inner lid 104 flow path 105 valve 106 pump 110 circulation period 111 inlet portion 112 outlet portion 200 driving battery 1000 temperature control system

Claims

1. A heater unit mounted on a heating device for an electric vehicle, comprising: a ceramic heater having a heating element; a heat sink including a first surface facing the ceramic heater and a second surface having a heat dissipation surface different from the first surface; and a heat conductive member disposed between the first surface of the heat sink and the ceramic heater, the heat conductive member being in contact with both the ceramic heater and the first surface, wherein the heat conductive member has at least one of higher elasticity, ductility, and malleability than the ceramic heater and the heat sink.

2. The heater unit according to claim 1, wherein the ceramic heater is mainly composed of alumina.

3. The heater unit according to claim 1, wherein the heat sink is mainly made of aluminum.

4. The heater unit according to claim 1, wherein said heat conducting member is graphite.

5. The heater unit according to claim 1, wherein the heat conductive member is aluminum foil.

6. The heater unit according to claim 5, wherein the heat conductive member is laminated.

7. The heater unit according to claim 1, wherein the heat conducting member covers the entire surface of the ceramic heater and the entire surface of the heat sink in the region where the ceramic heater and the heat sink face each other.

8. A heater unit according to claim 1, wherein the heat sink is composed of at least two members, and the heat sink has a housing portion for housing the ceramic heater.

9. The heater unit according to claim 8, wherein the heat sink has a recess, and the ceramic heater and the heat conductive member are located in the recess.

10. The heater unit according to claim 8, further comprising a compression member for compressing said heat sink, said compression member being a leaf spring.

11. The heater unit according to claim 8, wherein the housing has an opening on one end surface of the heat sink, and the ceramic heater protrudes from the opening to the outside of the housing.

12. The heater unit according to claim 11, wherein the heat conductive member protrudes from the opening to the outside of the housing portion.

13. The heater unit according to claim 8, wherein the heat sink comprises at least a first member and a second member, and the first member and the second member are joined by brazing or welding.

14. The heater unit according to claim 1, wherein the heat sink comprises a pipe, and the heat dissipation surface is disposed on at least a portion of an inner surface of the pipe.

15. The heater unit according to claim 14, wherein a plurality of the ceramic heaters are arranged along the axial direction of the pipe.

16. A heater unit as described in claim 14, wherein a plurality of structures each comprising the ceramic heater, the heat sink, and the heat conductive member are stacked, and a second heat conductive member having at least one of higher elasticity, ductility, and malleability than the ceramic heater and the heat sink is disposed in an area where the ceramic heater and the heat sink of each of the different structures face each other.

17. A heater unit as described in claim 1, comprising a housing having an opening, the heat sink being positioned in the vicinity of the opening and covering the opening with the heat dissipation surface, and at least one surface inside the housing and the heat dissipation surface forming a flow path.

18. The heater unit according to claim 17, wherein at least one surface on the inside of the housing is provided with a first groove-like portion, the first groove-like portion constituting at least a portion of the flow path.

19. The heater unit according to claim 17, wherein the heat dissipation surface includes a second groove-like portion, the second groove-like portion forming at least a portion of the flow path.

20. A heating device for an electric vehicle, comprising: the heater unit according to claim 1; and a circulation mechanism for circulating the thermal solvent heated by the heater unit.

21. A heating device for an electric vehicle, comprising: a heater unit as described in claim 11; a circulation mechanism for circulating a thermal solvent heated by the heater unit; and a container body for storing the thermal solvent during circulation, wherein at least a portion of the heater unit is contained in the container body and at least a portion of the heat dissipation surface is in contact with the thermal solvent.

22. A heating device for an electric vehicle, comprising: a heater unit according to claim 14; and a circulation mechanism for circulating a thermal solvent heated by said heater unit, wherein said thermal solvent flows through said pipe of said heat sink.

23. A heating device for an electric vehicle, comprising: a heater unit according to claim 17; and a circulation mechanism for circulating a thermal solvent heated by said heater unit, said thermal solvent flowing through said flow path.

24. A temperature control system for an electric vehicle, comprising: a heater unit as described in claim 1; a thermal solvent that is heated by at least the heater unit; a heat pump unit capable of adjusting the temperature of the thermal solvent; a circulation mechanism that circulates the thermal solvent; and a control unit, wherein the control unit controls the operation of the circulation mechanism to select a flow path so that the thermal solvent flows to at least one of the heater unit or the heat pump unit.

25. A temperature control system as described in claim 24, further comprising a temperature sensor capable of detecting the temperature of a temperature-controlled portion in the electric vehicle, wherein the control portion causes the hot solvent to flow through the heater unit when the temperature detected by the temperature sensor is below a specific temperature, and causes the hot solvent to flow through the heat pump unit when the detected temperature is equal to or higher than the specific temperature.

26. An electric vehicle equipped with the heater unit according to claim 1.

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