Thermal Management System

Abstract

Described herein is a system for thermal management of a component, such as a battery for an electric vehicle. The system comprises an electrical component and one or more panels thermally coupled to the electrical component. Each panel comprises a plurality of passages for conveying a working fluid around the panel. The one or more panels are arranged to form a hermetically sealed system such that the working fluid is configured to communicate heat energy around the sealed system. The system further comprises a heat exchanger mechanism in thermal communication with at least one of the plurality of panels so as to communicate heat energy to and/or from the electrical component via the plurality of panels.

Claims

1. A system comprising: an electrical component; a plurality of panels coupled, both fluidly and mechanically, to form a structure that is arranged around and thermally coupled to the electrical component, each panel comprising a plurality of passages configured to convey a working fluid around the panel, the plurality of panels being arranged to form a hermetically sealed system such that the working fluid can passively circulate around the sealed system to communicate heat energy around the sealed system; and a heat exchanger mechanism in thermal communication with at least one of the plurality of panels so as to communicate heat energy to and/or from the electrical component via the plurality of panels.

2. The system of claim 1, wherein, for each of the plurality of panels, the plurality of passages comprises one or more primary passages and one or more secondary passages.

3. The system of claim 2, wherein the one or more primary passages extend in a direction perpendicular to a direction in which the one or more secondary passages extend.

4. (canceled)

5. The system of claim 1, wherein the plurality of panels are arranged to substantially surround the electrical component.

6. The system of claim 1, wherein the plurality of panels are arranged to form a box defining a cavity in which the electrical component is located.

7. The system of claim 1, wherein the plurality of panels are fluidly coupled to one another through the primary passages.

8. The system of any of claim 7, wherein the primary passages are fluidly coupled through respective joining members, each joining member having one or more passages of a cross-sectional area greater than a cross-sectional area of the primary passages.

9. The system of claim 8, wherein the joining members are further arranged to mechanically couple the plurality of panels.

10. (canceled)

11. The system of claim 1, wherein the working fluid comprises a working fluid in both liquid and gaseous phases, and wherein the working fluid is configured to communicate heat energy around the sealed system through evaporation of the liquid at one location of the sealed system and condensation of the liquid at a different location of the sealed system.

12. The system of claim 1, wherein the working fluid is water.

13. The system of claim 1, wherein the electrical component is a battery.

14. The system of claim 1, further comprising one or more fluid pumps arranged to pump the working fluid through the heat exchanger.

15. The system of claim 14, further comprising: a heat tank configured to provide a heating fluid as the working fluid, wherein in an active heating mode of operation, the one or more fluid pumps are arranged to pump the heating fluid through a first inlet of the heat exchanger.

16. The system of claim 14, further comprising: a low temperature storage device configured to provide a cooling fluid as the working fluid, wherein in an active cooling mode of operation, the one or more fluid pumps are arranged to pump the cooling fluid through a second inlet of the heat exchanger.

17. The system of claim 1, wherein the fluid is a refrigerant.

18. The system of claim 1, wherein the heat exchanger mechanism comprises a thermoelectric device.

19. A vehicle comprising the system of claim 1.

20. The system of claim 1, wherein the plurality of panels are directly coupled.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The following description is with reference to the following Figures:

[0020] FIG. 1 shows a perspective view of an example of a system as described herein;

[0021] FIG. 2 shows a perspective view of a plurality of panels of the system of FIG. 1;

[0022] FIG. 3A shows a perspective view of an example of two panels as described herein;

[0023] FIG. 3B shows a section of the panels of FIG. 3A;

[0024] FIG. 3C shows a section of the cross section of FIG. 3B;

[0025] FIG. 3D shows a cross section of the panels of the FIG. 3A;

[0026] FIG. 4 schematically illustrates components which make up a panel;

[0027] FIG. 5 shows a perspective view of an example heat exchanger of the system of FIG. 1; and

[0028] FIG. 6 schematically illustrates example implementations of the system of FIG. 1.

DETAILED DESCRIPTION

[0029] With reference to FIG. 1, a system 100 for thermal management of an electrical component 102 is described. Optionally, system 100 may be provided within a vehicle 140 (see FIG. 6). Vehicle 140 may be an electric vehicle. Alternatively, system 100 may be a static or stationary arrangement, for example, a system for the thermal management of a battery or other energy storage device in a domestic or commercial application.

[0030] System 100 comprises one or more panels 106. Each panel 106 comprises a plurality of passages for conveying a working fluid around the panel. These passages are internal to the panel, i.e. are formed within cavities within the panels 106. The one or more panels are arranged to form a hermetically sealed system such that the working fluid is configured to communicate heat energy around the sealed system formed of the passages of each panel 106.

[0031] In some arrangements, one panel may be provided. Alternatively, two or more panels may be provided, either arranged independently of the other panels to form separate hermetically sealed systems, or fluidly coupled to one another in any suitable configuration to form one or more hermetically sealed systems through which the working fluid can be conveyed. For example, two panels may be independently arranged on long sides of electrical component 102, or four panels may be arranged as to surround the electrical component in a band (i.e., to be provided on both two long and two short sides of the component). These four panels may comprise independent sealed systems, or may be joined to form one or more sealed systems for the working fluid to circulate within.

[0032] The one or more panels 106 are thermally coupled to the electrical component 102 to communicate heat energy to or from the electrical component 102. In the following description, electrical component 102 is a battery 102 comprising a plurality of battery cells 104, but system 100 may be employed for the thermal management of any other suitable electrical component which requires in-situ cooling (or heating), for example, the cooling of components of a processor or other electrical system. For example, system 100 can be employed for the in-situ cooling (or heating) of a generator or processor, or an electrical component such as a transformer, a capacitor, a resistor, or an inductor.

[0033] System 100 further comprises a heat exchanger mechanism 108 which is in thermal communication with at least one of panels 106 so as to communicate heat energy to and/or from the electrical component 102 such as the battery via the panels 106. The one or more panels 106 may be thermally coupled to the heat exchanger mechanism 108 using a thermal paste or gel. The heat exchanger may then be mechanically clamped onto one of the panels 106. For a permanent coupling, thermal adhesive may instead be used.

[0034] In the following description, the working fluid comprises a working fluid in both liquid and gaseous phases, wherein the working fluid is configured to communicate heat energy around the sealed system through evaporation of the liquid at one location of the sealed system and condensation of the liquid at a different location of the sealed system. In other words, the working fluid passively circulates around the sealed system. The panels thus operate as heat pipes to communicate heat energy around the sealed system. The working fluid used in the system described herein may be water or ammonia, for example. However, there are a multitude of working fluids that can be used including water, ammonia, acetone, alcohols and blends thereof; the efficacy of these are driven by the conditions in which the panel is used. The skilled person will be able to identify suitable fluids for any given set of working conditions and temperature operating ranges.

[0035] It is also envisaged that in other arrangements the working fluid is arranged merely to communicate heat energy around the sealed system without evaporation and/or condensation mechanisms. For example, the working fluid may be water or a refrigerant, and the heat exchanger mechanism may be arranged to actively circulate said working fluid around the sealed system, by way of a pump or a compressor, for example.

[0036] As described further with reference to FIG. 2, it can be seen that in some examples the panels 106 can be arranged to substantially surround the cells 104 of the battery 102. In particular, the panels 106 are arranged to form a box defining one or more cavities 107 in which the battery 102, or any other suitable electrical component, can be located. It will be understood that the box formed by the panels 106 may take any suitable form or shape. In some arrangements, the cavities 107 may be entirely enclosed by the panels 106, in other arrangements, the box shown in FIG. 2 may be open on more than one side. Fewer panels can provide easier instalment of the electrical component 102 inside the cavities 107, and may also reduce the cost and complexity of manufacturing of the system. For example, as described above, two independent panels may be used or a band of four panels may be used.

[0037] With reference to FIGS. 3A-3D, a structure of the panels is described in more detail. Two panels 106a, 106b are described here, mechanically and fluidly coupled to one another by a joining member 110, but it will be understood that more than two panels may be provided, or that the joining member no may be omitted and the panels 106a, 106b may be directly coupled, both mechanically and fluidly, to one another.

[0038] With reference to FIGS. 3B and 3C, a section N-N of panel 106a and joining member no is described, with details of the section being further illustrated in Section R. It can be seen that panel 106a comprises two primary passages 112 and a plurality of secondary passages 114; the primary and secondary passages are in fluid communication. In some arrangements, the secondary passages extend in a direction that is generally perpendicular to that in which the primary passages 112 extend. In some arrangements, each of the one or more primary passages can have a cross-sectional area greater than a cross-sectional area of each of the one or more secondary passages, but it will be understood that the cross sectional area of the secondary passages 114 may be larger than that of the primary passages in some arrangements, due to the increase in area which may be provided by the inclusion of protrusions or other features within the secondary passages.

[0039] As illustrated in FIGS. 3C and 3D, the joining member no comprises a passage 116 which extends in a direction parallel to the secondary passages 114 in this arrangement (in FIG. 3D, both the secondary passages 114 and passage 116 extend out of the page). Secondary passage 112 is fluidly coupled to the passage 116 by passage section 117. The joining member 110 further comprises a passage 118 (here extending out of the page as viewed in FIG. 3C) which fluidly couples the secondary passage 112 of panel 106a to the corresponding secondary passage of 106b. In other words, panels 106a and 106b can be fluidly coupled to one another through the secondary passages 112 via the passages 116, 117 and 118 of joining member 110.

[0040] The passages 116, 117, 188 of each joining member no have a cross-sectional area greater than a cross-sectional area of the primary passages. This arrangement may provide for simpler manufacturing and assembly of the panels, as well as facilitating the improved flow of fluid around the sealed system. In particular, when the passages of the joining member have a greater diameter than the diameter of the primary passages 112, fluid may flow more effectively around the corners shown in Section R and FIG. 3D; fluid can thus flow more effectively between the two panels 106a, 106. More effective heat transfer between panels may therefore be provided.

[0041] FIG. 3D also illustrates an example cross section of the secondary passages 114, the features of which can provide an increased surface area between the material of the body of the panel 106a, 10b and the cavities within the body which define the secondary passages 114. The geometry of these secondary passages is described in more detail with reference to FIG. 4 of earlier filed UK patent application GB1410924.3 (GB2527338-A), FIG. 4 of which application, and its accompanying description, is hereby incorporated by reference in regard to the geometry of these passages.

[0042] The panels 106 can be positioned horizontally or vertically, with the secondary passages 114 arranged horizontally (or generally horizontally) or vertically (or generally vertically). In the examples described with reference to FIGS. 3A-3D, the secondary passages 114 are arranged to lie generally horizontally, such that condensation and evaporation of the working fluid occurs within the cross section of the secondary passages across the panel (rather than the case where the secondary passages are orientated, vertically such that condensed working fluid falls to the bottom of the panel 106). Changes in internal pressures and temperature gradients can facilitate movement of the working fluid around the sealed system, as will be described below in more detail. The skilled person will understand that any suitable orientation of the secondary passages 114 may be provided.

[0043] With reference to FIG. 4, it will be understood that each panel 106 may be manufactured by extrusion, or by any other suitable manufacturing process. For example, the main body 132 of each panel 106 may be formed of extruded aluminium or an aluminium alloy. Extrusion can enable complex geometries of secondary passages 114 to be formed, which may facilitate improved phase change of the working fluid and thus improved heat transfer. Aluminium is also relatively inexpensive, has good anti-corrosion properties, and is easy to work in a manufacturing process. Due to the structural strength within the aluminium extrusion, when system 100 comprising the panels 106 is incorporated into a vehicle, optionally an electric vehicle, the panels can be used to provide righty to the vehicle. Alternatively, an aluminium alloy or another metal such as steel may be used.

[0044] Optionally, each panel further comprises one or more manifolds 134, which define, or contribute to defining, the primary passages 112 of each panel. The manifolds 134 are substantially straight. The manifolds 134 are formed of the same material as panel main body 132 and may be coupled to edges of the main body 132 of each panel to allow the primary passages to be fluidly coupled via the secondary passages; in particular, the secondary passages 114 are commonly terminated at each end of the panel body 132 by the manifold 134, sealing the passages which in turns form a liquid- and gas-tight chamber. Interference fitting, welding or gluing can be used to embed the manifold onto the panel main body 132, in the process forming a sealed chamber within the panel 106. The formation of the secondary passages 114 within the panel main body 132 and the use of the manifolds 134 can facilitate relatively straightforward sealing of the plurality of passages, since only a single seal is required at either end of the panel main body 132. Advantageously, the mechanical mounting of the manifolds 134 on the panel main body 132 also forms the seal.

[0045] With reference to FIG. 5, a heat exchanger mechanism 108 is described which is connected, either directly or indirectly, with a fluid to remove or deliver heat energy to the electrical component 102 as required by system 100. The heat exchanger mechanism 108 described herein is a thermoelectric assembly (i.e. a Peltier device) comprising a cold side plate 120, which may be formed of aluminium, a hot side plate 124 and foam insulation 124 separating the hot and cold sides and containing thermoelectric modules. The hot plate side 124 comprises channels for receiving a fluid. The fluid may be in fluid communication with a heat sink, for example, to absorb excess heat from the electrical component 102 to which the heat exchanger mechanism 108 is thermally coupled via the panels 106.

[0046] In other arrangements, the heat exchanger mechanism may not be thermoelectric assembly. Instead, the heat exchanger 108 may be any other suitable form of heat exchanger mechanism. For example, the heat exchanger mechanism can comprise the passing of cold/hot air over the panels, or a thermal fluid running through the heat exchanger mechanism. The skilled person will understand how to choose a suitable heat exchanger for specific applications of system 100. For example, when system 100 is incorporated within a vehicle, passive cooling of the panels may be provided by arranging channels which force air over the panels when the vehicle is moving. Moreover, as described above, when a working fluid is a refrigerant or water or the like, the heat exchange mechanism may be arranged to actively circulate said fluid within the sealed system in addition to exchanging heat between the system and the environment.

[0047] As described with reference to FIG. 6, the heat exchanger mechanism 108 may be in fluid communication with one or more fluid pumps 126 of system 100, the fluid pump(s) 126 arranged to pump fluid through the heat exchanger 108 to communicate heat energy to and/or from the electrical component 102 via the plurality of panels 106. Optionally, the fluid being provided to the heat exchanger is a refrigerant.

[0048] In some arrangements, system 100 may further comprise a heat tank 128 and/or a cold tank or other low temperature storage device 130 for storing a cooling fluid. The heat tank 128 is for providing a heating fluid to the heat exchanger 108, wherein in an active heating mode of operation, the one or more fluid pumps 126 are arranged to pump the heating fluid through a first inlet 128a of the heat exchanger. The cold temperature storage device 130 is for providing a cooling fluid to the heat exchanger 108, wherein in an active cooling mode of operation, the one or more fluid pumps 126 are arranged to pump the cooling fluid through a second inlet 130a of the heat exchanger 108.

[0049] In order to use the panels 106 to cool the electrical component, i.e. to transfer heat away from the electrical component 102 to environment via the heat exchanger 108, a cooling fluid (for example a liquid or vapour) at a temperature that is at least a few Kelvin lower than the panels is provided from the low temperature storage device 130 to the heat exchanger mechanism 108. Heat energy is then transferred from the panels 106, thermally coupled to the heat exchanger, to the heat exchanger. In response to this flow of heat energy, a portion of the sealed system through which the working fluid circulates is cooled, causing a vapour phase of the working fluid to condense within the secondary passages 114 of the panel 106. Upon condensing, the vapour releases the stored latent heat to the material of the panel 106 which is adjacent the passage in which the working fluid condensed; this latent heat can then be removed from the system through the heat exchanger 108.

[0050] The condensing of the working fluid also causes a low pressure region to form. Vapour from other portions of the sealed system then travels towards the cooler, lower pressure, areas of the sealed system, causing the condensed liquid to also travel around the sealed system away from the cooler section and to a warmer portion of the sealed system by the action of gravity and the internal pressures within the sealed system (for example from gas pressure resulting from the evaporation-condensation cycle within the panel). The heat energy in the warmer part of the sealed system evaporates the working fluid, turning it from liquid to vapour through the absorption of latent heat of evaporation. This evaporation thus uses more heat energy than does heating without phase change. The heated vapour travels around the sealed system along the passages 112, 114 towards the cooler, lower pressure regions, and again condenses in a cooler part of the sealed system near the heat exchanger 108. The vaporization-condensation cycle can then repeat again. The skilled person will understand how the process may be reversed to cause the panels 106 to warm the electrical component 102 by providing a heating fluid from the heat tank 128 to the heat exchanger mechanism 108.

[0051] The above described effect causes heat energy to be distributed substantially evenly across the panels 106, which are in thermal communication with the electrical component 102, and thus can cause the heat energy to be distributed evenly across the electrical component also. As such, temperature differences between different locations around the system are minimised. Moreover, the amount of heat energy that is transferred is significantly greater than can be achieved through conduction by an inexpensive metal of comparable weight and size to the panels 106 by use of a working fluid as described herein. This is achieved without the use of any wicking structure or material. More energy efficient cooling of an electrical component can therefore be provided.

[0052] Any of the implementations of system 100 described above may be implemented within vehicle 140, as illustrated in FIG. 6. Optionally, vehicle 140 is an electric vehicle or a hybrid vehicle which uses two or more distinct types of power; for example, a hybrid vehicle may use an internal combustion engine to drive an electric generator that powers an electric motor. Vehicle 140 may be a car, a bus, a train, a lorry, or any other suitable vehicle. Alternatively, any of the above described implementations of system 100 may be implemented a static or stationary system arrangement, for example, a as a system for the thermal management of a battery or other energy storage device in a domestic or commercial application, or for the in-situ thermal management of a generator or processor or another electrical component or device.

[0053] It is noted herein that while the above describes various examples of system, these descriptions should not be viewed in a limiting sense. Rather, there are several variations and modifications which may be made without departing from the scope of the present invention as defined in the appended claims.