Coolant-refrigerant heat exchanger with induction heater and thermal management system

Abstract

In one aspect, a coolant-refrigerant heat exchanger for a thermal management system for an electric vehicle is provided. The coolant-refrigerant heat exchanger includes a plurality of flow plates and an auxiliary heater. A plurality of flow plates are sealingly joined together to define a coolant flow path through the coolant-refrigerant heat exchanger and a refrigerant flow path through the coolant-refrigerant heat exchanger. The coolant flow path and the refrigerant flow path are positioned to transfer heat from one of the coolant and the refrigerant to the other. The flow plate is made of an electrically conductive material. An auxiliary heater is positioned to heat both refrigerant and coolant in the coolant-refrigerant heat exchanger. The auxiliary heater includes an induction coil positioned proximate the flow plate and energizable to heat the flow plate by induction.

Description

[0001] Cross - reference to related applications

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 381,784, filed on November 1, 2022, and U.S. Provisional Application No. 63 / 491,138, filed on March 20, 2023, the contents of both of which are incorporated herein by reference in their entireties. Technical field

[0003] The present disclosure generally relates to the field of heat exchangers, and more particularly, to coolant - refrigerant heat exchangers and associated thermal management systems for use in electric vehicles. Background art

[0004] It is known that thermal management systems in electric vehicles (EVs) employ coolant heaters for the purpose of heating the coolant, which ultimately circulates through components of the EV that need to be heated for performance reasons, such as the vehicle's traction battery. Additionally, refrigerant heaters are known to be used in EVs for certain specific purposes. However, each of the existing thermal management systems has certain drawbacks. Improving the performance and efficiency of EV thermal management systems remains a continuous concern. Summary of the invention

[0005] In one aspect, a coolant - refrigerant heat exchanger for a thermal management system for an electric vehicle is provided. The coolant - refrigerant heat exchanger includes a plurality of flow plates and an auxiliary heater. The plurality of flow plates each have a plurality of faces and a peripheral edge. The plurality of flow plates are sealingly joined together to define a coolant flow path through the coolant - refrigerant heat exchanger and a refrigerant flow path through the coolant - refrigerant heat exchanger. The coolant flow path and the refrigerant flow path are positioned to transfer heat from one of the coolant and the refrigerant to the other of the coolant and the refrigerant. The flow plates are made of a conductive material. The auxiliary heater is positioned to heat both the refrigerant and the coolant in the coolant - refrigerant heat exchanger. The auxiliary heater includes an induction coil that is positioned adjacent to the flow plates and is capable of being energized to inductively heat the flow plates.

[0006] Other aspects of the present disclosure may also be patentable. Brief description of the drawings

[0007] The foregoing and other aspects of the invention will be better understood with reference to the accompanying drawings, which are as follows:

[0008] Figure 1 is a schematic diagram of a basic vehicle air - conditioning system using refrigerant according to the prior art.

[0009] Figure 2 is for Figure 1The pressure-enthalpy diagram of the refrigerant in the air conditioning system shown in

[0010] Figure 3A is a schematic diagram of a basic vehicle heat pump system according to the prior art in the cooling mode.

[0011] Figure 3B is Figure 3A a schematic diagram of the heat pump system shown in

[0012] Figure 4 is for Figure 1 the pressure-enthalpy diagram of the refrigerant in the air conditioning system shown in

[0013] Figure 5 a schematic diagram of a vehicle thermal management system including a coolant system and a refrigerant system according to an embodiment of the present disclosure.

[0014] Figure 6 is a perspective view of a coolant-refrigerant heat exchanger according to an embodiment of the present disclosure, the coolant-refrigerant heat exchanger including an auxiliary heater.

[0015] Figures 7a and 7b together are Figure 6 a perspective exploded view of the coolant-refrigerant heat exchanger shown in

[0016] Figure 8 is Figure 6 an enlarged perspective view of a part of the coolant-refrigerant heat exchanger shown in

[0017] Figure 9 is Figure 6 a perspective sectional view of the coolant-refrigerant heat exchanger shown in

[0018] Figure 10 is Figure 10 a partial exploded perspective view of a part of the coolant-refrigerant heat exchanger shown in , which illustrates the flow of the coolant and the refrigerant therethrough.

[0019] Figure 11 is a schematic illustration showing the flow of the coolant and the refrigerant through Figure 6 the coolant-refrigerant heat exchanger shown in

[0020] Figure 12 is a schematic illustration showing an alternative flow path for the coolant and the refrigerant for an alternative embodiment of the coolant-refrigerant heat exchanger through Figure 6 the coolant-refrigerant heat exchanger shown in

[0021] Figure 13 is according to an embodiment of the present disclosure incorporating Figure 6Schematic illustration of a thermal management system of a coolant-refrigerant heat exchanger in a cabin heating mode using an auxiliary heater.

[0022] Figure 14 is a side view of an electric vehicle incorporating the Figure 13 thermal management system shown in

[0023] Figure 15 is a pressure-enthalpy diagram of the refrigerant in the Figure 13 thermal management system shown in

[0024] Figure 16 is a flowchart of a method for controlling the auxiliary heater shown in Fig. 7b when the thermal management system operates in the Figure 13 mode shown in

[0025] Figure 17 is a cross-sectional side view of a part of a plurality of flow plates that are part of the Figures 6 to 10 coolant-refrigerant heat exchanger shown in

[0026] Figure 18 is a perspective view of a formed flow plate assembly that serves as part of a coolant-refrigerant heat exchanger according to another embodiment.

[0027] Figure 19 is a coolant-refrigerant heat exchanger according to another embodiment of the present disclosure, in which an induction coil is wound around the flow plate assembly.

[0028] Figure 20 is a Figure 19 front view of the coolant-refrigerant heat exchanger shown in

[0029] Figure 21 is a front view of a coolant-refrigerant heat exchanger according to another embodiment of the present disclosure, which is similar to the Figure 19 embodiment shown in

[0030] Figure 22 is a front view of a coolant-refrigerant heat exchanger according to another embodiment of the present disclosure, which is similar to the Figure 21 embodiment shown in

[0031] Figure 23 is a perspective view of a coolant-refrigerant heat exchanger according to another embodiment of the present disclosure, which includes a carrier that includes at least one groove for holding an induction coil.

[0032] Figure 24 is a front view of a coolant - refrigerant heat exchanger according to another embodiment of the present disclosure, which embodiment includes at least one base.

[0033] Figure 25 is Figure 24 a perspective view of the coolant - refrigerant heat exchanger shown in

[0034] Figure 26 is a front view of a coolant - refrigerant heat exchanger according to another embodiment of the present disclosure, which embodiment is similar to Figure 24 the embodiment shown in

[0035] Figure 27 is a front view of a coolant - refrigerant heat exchanger according to another embodiment of the present disclosure, which embodiment is similar to Figure 24 the embodiment shown in

[0036] Figure 28 is a front view of a coolant - refrigerant heat exchanger according to another embodiment of the present disclosure, which embodiment is similar to Figure 24 the embodiment shown in

[0037] Figure 29 is a front view of a coolant - refrigerant heat exchanger according to another embodiment of the present disclosure, which embodiment includes a plurality of C - shaped bases.

[0038] Figure 30 is a front view of a coolant - refrigerant heat exchanger according to another embodiment of the present disclosure, which embodiment includes a plurality of C - shaped bases having at least one groove.

[0039] Figure 31 is Figure 30 an enlarged cross - sectional view of a part of the coolant - refrigerant heat exchanger shown in

[0040] Figure 32 is a front view of a coolant - refrigerant heat exchanger according to another embodiment of the present disclosure, which embodiment includes at least one base inserted into the body of the flow plate assembly.

[0041] Figure 33 is Figure 32 an enlarged cross - sectional view of a part of the coolant - refrigerant heat exchanger shown in

[0042] Figure 34 FIG. 144 is an exploded perspective view of a coolant - refrigerant heat exchanger according to another embodiment of the present disclosure, which embodiment includes at least one base inserted into the interior of a flow plate assembly, and in which embodiment, at least one induction coil is present inside each of the at least one base.

[0043] Figure 35 is Figure 34 a cross - sectional perspective view of the coolant - refrigerant heat exchanger shown in FIG. 147. DETAILED DESCRIPTION

[0044] For simplicity and clarity of illustration, where considered appropriate, reference numerals may be repeated in the figures to indicate corresponding or like elements. Additionally, numerous specific details are set forth to provide a thorough understanding of one or more embodiments described herein. However, one of ordinary skill in the art will understand that the embodiments described herein may be practiced without these specific details. In other instances, well - known methods, procedures, and components have not been described in detail so as not to obscure the embodiments described herein. First, it should be understood that although the exemplary embodiments are illustrated in the figures and described below, the principles of the present disclosure may be implemented using any number of techniques, whether currently known or not. The present disclosure should not in any way be limited to the exemplary implementations and techniques illustrated in the figures and described below.

[0045] Unless the context otherwise indicates, the various terms used throughout this specification may be read and understood as follows: The "or" used throughout is inclusive, as if written "and / or"; the singular articles and pronouns used throughout include their plural forms, and the plural articles and pronouns used throughout include their singular forms; similarly, gender pronouns include their corresponding pronouns such that the pronouns should not be understood as restricting anything described herein to use, implementation, execution, etc. by a single gender; "exemplary" should be understood as "illustrative" or "by way of example" and is not necessarily to be understood as "preferred" to other embodiments. Further definitions of terms may be set forth herein; as will be understood by reading this specification, these definitions may apply to prior and subsequent instances of those terms.

[0046] Modifications, additions, or omissions may be made to the systems, apparatuses, and methods described herein without departing from the scope of the disclosure. For example, components of the systems and apparatuses may be integrated or separated. Additionally, the operations of the systems and apparatuses disclosed herein may be performed by more, fewer, or other components, and the methods described may include more, fewer, or other steps. Additionally, the steps may be performed in any suitable order. As used in this document, "each" refers to each member of a group or each member of a subgroup of a group.

[0047] The indefinite article "a" is not intended to be limited to meaning "one" element of a group. Where appropriate, it is intended to mean "one or more" elements of a group (i.e., unless it is clear from the context that only one element of the group is appropriate).

[0048] Any reference to up, down, top, bottom, etc. is intended to refer to the orientation of a particular element during use of the claimed subject matter, and not necessarily its orientation during transportation or manufacture. For example, the upper surface of an element may still be considered the upper surface of the element even when the element is lying on its side.

[0049] Description of a basic air conditioning system

[0050] Referring to Figure 1 , which shows a schematic diagram of a typical vehicle air conditioning system 10 according to the prior art. It will be noted that Figure 1 the air conditioning system 10 shown in

[0051] Figure 1 has been simplified in a sense, and for simplicity, several components that are normally present have been omitted herein.

[0052] The refrigerant enters the compressor 14 at a relatively low pressure, say for example about 140 kPa, and a relatively low temperature, say for example -25 degrees Celsius. The compressor 14 compresses the refrigerant so that the refrigerant reaches a high pressure, say for example about 1200 kPa. The compression of the refrigerant raises its temperature to, for example, about 110 degrees Celsius. Thus, the refrigerant is a high-pressure, high-temperature gas when it leaves the compressor. The refrigerant then travels to the condenser 16. The condenser 16 is used to condense the refrigerant by effecting heat transfer from the refrigerant flowing through it to the air surrounding the condenser 16. In embodiments in which the vehicle includes an engine, the condenser 16 is positioned outside the passenger compartment 12, such as in the engine compartment shown at 21. As a result of the placement of the condenser 16, the condenser 16 is exposed to the outside air shown at 22 (this outside air is the air from outside the passenger compartment 12), which is distinct from the inside air shown at 24 (this inside air is the air from inside the passenger compartment 12). An outside fan 26 is provided to enhance the flow of the outside air 22 over the condenser 16. The temperature of the outside air 22 is lower than the temperature of the refrigerant, and thus the refrigerant condenses in the condenser 16 and leaves the condenser 16 as a liquid.

[0053] The refrigerant then passes through the expansion valve 18 in order to reduce the pressure of the refrigerant. Some of the refrigerant in the refrigerant may evaporate due to the reduction in pressure; however, a large portion of the refrigerant remains in liquid form. The reduction in the pressure of the refrigerant cools the refrigerant. Thus, the refrigerant leaves the expansion valve 18 as a low-pressure, low-temperature liquid or liquid / gas mixture. The refrigerant then passes through the evaporator 20, which transfers heat from the inside air 24 to the refrigerant to raise the temperature of the refrigerant in order to drive the evaporation of the refrigerant. An inside fan 28 may be provided to facilitate the flow of the inside air 24 over the evaporator 20. The evaporator 20 is positioned inside the passenger compartment 12, in the sense that the evaporator 20 may be positioned behind the firewall that separates the engine compartment 21 from the passenger compartment 12 in the vehicle, and more importantly, the evaporator 20 is exposed to the inside air 24 flow. For greater clarity, the inside air 24 is the air that is directed into the passenger compartment 12. The increase in the temperature of the refrigerant in the evaporator 20 correspondingly cools the inside air 24, thereby cooling the inside air 24.

[0054] The refrigerant then leaves the evaporator 20 and returns to the inlet of the compressor 14, where the refrigerant is compressed again and sent to the condenser 16 again in a continuous cycle.

[0055] Description of a basic pressure-enthalpy diagram

[0056] Figure 2It is a pressure-enthalpy diagram that graphically shows the refrigeration cycle through which the refrigerant passes. As those skilled in the art will understand, the inverted U-shaped line represents the gas / liquid transition properties of the refrigerant. The dotted line curve shown at 30 represents the property changes of the refrigerant as it passes through the Figure 1 refrigeration cycle shown therein. Point 32 represents the properties of the refrigerant immediately upstream of compressor 14. Curve segment 30a represents the change in the properties of the refrigerant due to the operation of compressor 14. Point 34 represents the properties of the refrigerant downstream of compressor 14 and upstream of condenser 16. As can be seen, the pressure and temperature of the refrigerant increase between point 32 and point 34.

[0057] Curve segment 30b represents the change in the properties of the refrigerant due to the operation of condenser 16. Point 36 represents the properties of the refrigerant immediately downstream of condenser 16 (and thus upstream of expansion valve 18). As can be seen, the temperature of the refrigerant decreases and then remains constant during the phase change that occurs in condenser 16.

[0058] Curve segment 30c represents the change in the properties of the refrigerant due to expansion valve 18. Point 38 represents the properties of the refrigerant immediately downstream of expansion valve 18 (and thus upstream of evaporator 20). As can be seen, the pressure and temperature of the refrigerant decrease due to passing through the expansion valve.

[0059] Curve segment 30d represents the change in the properties of the refrigerant due to passing through evaporator 20. After passing through evaporator 20, the refrigerant returns to point 32, which represents the properties of the refrigerant immediately downstream of evaporator 20 (and thus represents the properties of the refrigerant immediately upstream of compressor 14). As can be seen, the pressure and temperature remain substantially constant in evaporator 20. As those skilled in the art will understand, this is because the heat transferred to the refrigerant is used to drive the phase change (i.e., evaporation) of the refrigerant, which occurs at a constant temperature. Optionally, evaporator 20 can be sized to transfer slightly more heat to the refrigerant than the minimum amount of heat required to evaporate all of the refrigerant, so as to drive the temperature of the refrigerant to increase once all of the refrigerant has been evaporated. This ensures that all of the refrigerant leaves the evaporator as a gas, without any portion remaining as a liquid. Advantageously, all of the refrigerant is in gaseous form when it reaches the inlet of compressor 14, so as to avoid damaging compressor 14.

[0060] Description of a basic heat pump system

[0061] Figure 3A and Figure 3B shows more than Figure 1The air conditioning system shown has a more complex thermal management system. The thermal management system can be referred to as a heat pump system and is shown at 40. The heat pump system 40 is similar to the air conditioning system 10 and includes a compressor 14 and an expansion valve 18, but also includes some different components. For example, the heat pump system 40 includes an external heat exchanger 42 and an internal heat exchanger 44 that respectively replace the condenser 16 and the evaporator 20 shown in Figure 1 . The heat pump system 40 also includes a reversing valve 46, which is further explained below. The heat pump system 40 is capable of cooling the passenger compartment 12 in a manner similar to the air conditioning system 10, but is also capable of heating the passenger compartment 12 with very little additional equipment.

[0062] The external heat exchanger 42 can be similar to the condenser 16 in the following sense: The external heat exchanger 42 can be used to perform heat transfer from the refrigerant flowing through it to the air surrounding the external heat exchanger 42 in order to condense the refrigerant, but can also receive a refrigerant liquid flow passing through it in the opposite direction to perform heat transfer from the air surrounding the external heat exchanger 42 to the refrigerant in order to evaporate the refrigerant.

[0063] The internal heat exchanger 44 can be similar to the evaporator 20 in the following sense: The internal heat exchanger 44 is located inside the passenger compartment 12 and can be used to perform heat transfer from the air surrounding the internal heat exchanger 44 to the refrigerant flowing through it in order to evaporate the refrigerant, but can also receive a refrigerant gas flow passing through it in the opposite direction to perform heat transfer from the refrigerant to the air surrounding the internal heat exchanger 44 in order to condense the refrigerant.

[0064] The reversing valve 46 can be positioned in a plurality of positions, the plurality of positions including: a first position ( Figure 3A ), in the first position, the reversing valve 46 transfers the refrigerant flow from the compressor 14 to the external heat exchanger 42 and from the internal heat exchanger 44 to the compressor 14; and a second position, in the second position, the reversing valve 46 transfers the refrigerant flow from the compressor 14 to the internal heat exchanger 44 and from the external heat exchanger 42 to the compressor 14.

[0065] The heat pump system 40 is capable of operating in a first mode ( Figure 3A ) and a second mode ( Figure 3B ), in the first mode, the reversing valve 46 is in the first position for cooling the passenger compartment 12, and in the second mode, the reversing valve 46 is in the second position for heating the passenger compartment 12.

[0066] The first mode ( Figure 3A)The description is as follows: The refrigerant enters the compressor 12 at a relatively low pressure and a relatively low temperature. The compressor 12 compresses the refrigerant so that the refrigerant reaches a high pressure, which raises its temperature. Thus, the refrigerant is a high-pressure and high-temperature gas when it leaves the compressor. The refrigerant then is conveyed to the external heat exchanger 42. The external heat exchanger 42 serves as a condenser and is used to condense the refrigerant by performing heat transfer from the refrigerant flowing through it to the external air 22 surrounding the external heat exchanger 42. Optionally, an external fan 26 is provided to enhance the air flow through the external heat exchanger 42 and thus enhance the heat transfer from the external heat exchanger 42. The refrigerant then passes through the expansion valve 18 to reduce the pressure of the refrigerant. Some of the refrigerant in the refrigerant may evaporate due to the pressure reduction, however, a large portion of the refrigerant remains in a liquid state. The reduction in the pressure of the refrigerant cools the refrigerant. Thus, the refrigerant leaves the expansion valve 18 as a low-pressure, low-temperature liquid or a liquid / gas mixture. The refrigerant then passes through the internal heat exchanger 44, which serves as an evaporator and transfers heat from the internal air 24 to the refrigerant (thereby cooling the internal air 24) to raise the temperature of the refrigerant in order to drive the evaporation of the refrigerant. Optionally, an internal fan 28 is provided and the internal fan 28 is used to enhance the air flow through the internal heat exchanger 44 and thus enhance the heat transfer from the internal air 24 to the refrigerant. The cooled internal air 24 cools the passenger compartment 12. The refrigerant then is conveyed to the inlet of the compressor 14, where the refrigerant is compressed again and is sent to the reversing valve 46 again in a continuous cycle.

[0067] Second mode ( Figure 3B)The description is as follows: The refrigerant enters the compressor 12 at a relatively low pressure and a relatively low temperature. The compressor 12 compresses the refrigerant so that the refrigerant reaches a high pressure, which causes its temperature to rise. Thus, the refrigerant is a high-pressure, high-temperature gas when it leaves the compressor 14. The refrigerant then travels to the internal heat exchanger 44, which serves as a condenser and is used to condense the refrigerant (thereby heating the internal air 24) by effecting heat transfer from the refrigerant flowing through it to the internal air 24 surrounding the internal heat exchanger 44. Optionally, an internal fan 28 is provided to enhance the air flow through the internal heat exchanger 44 and thus enhance the heat transfer from the refrigerant to the internal air 24. The heated internal air 24 heats the passenger compartment 12. The refrigerant then passes through the expansion valve 18 to reduce the pressure of the refrigerant. Some of the refrigerant in the refrigerant may evaporate due to the pressure reduction, however, a large portion of the refrigerant remains in the liquid state. The reduction in the pressure of the refrigerant cools the refrigerant. Thus, the refrigerant leaves the expansion valve 18 as a low-pressure, low-temperature liquid or liquid / gas mixture. The refrigerant then passes through the external heat exchanger 42, which serves as an evaporator and transfers heat from the external air 22 to the refrigerant to raise the temperature of the refrigerant to drive the evaporation of the refrigerant. Optionally, an external fan 28 is provided and the external fan 28 is used to enhance the air flow through the external heat exchanger 42 and thus enhance the heat transfer from the external air 22. The refrigerant then travels to the inlet of the compressor 14, where the refrigerant is compressed again and sent to the reversing valve 46 again in a continuous cycle.

[0068] Thus, by moving the reversing valve 46 between the first position and the second position, the heat pump system 40 can be used to heat or cool the passenger compartment as needed.

[0069] Figure 4 illustrates the refrigerant in Figure 3A and Figure 3B during the operation of the heat pump system 40 shown in the pressure-enthalpy diagram of the property changes experienced. As can be seen, Figure 4 the overall shape of the curve 30 in Figure 2 is similar to the shape of the curve 30 in

[0070] It should be noted that in a heat pump system, such as the heat pump system 40, regardless of whether the heat pump system 40 is operating in the first mode or the second mode, the refrigerant properties undergo the same cycle of compression, condensation, pressure reduction, and evaporation. Refer to Figure 4, point 32 corresponds to the properties of the refrigerant immediately upstream of the compressor as described above. Point 34 corresponds to the properties of the refrigerant downstream of the compressor 14 and upstream of the external heat exchanger 42 when operating in the first mode and the properties of the refrigerant downstream of the compressor and upstream of the internal heat exchanger 44 when operating in the second mode. Point 36 corresponds to the properties of the refrigerant downstream of the external heat exchanger 42 and upstream of the expansion valve 18 when operating in the first mode and the properties of the refrigerant downstream of the internal heat exchanger 44 and upstream of the expansion valve 18 when operating in the second mode. Point 38 corresponds to the properties of the refrigerant downstream of the expansion valve 18 and upstream of the internal heat exchanger 44 when operating in the first mode and the properties of the refrigerant downstream of the expansion valve 18 and upstream of the external heat exchanger 42 when operating in the second mode.

[0071] Description of a thermal management system having a coolant-refrigerant heat exchanger

[0072] Figure 5 Shows more complex than Figure 3A and Figure 3B The heat pump system 40 shown in. Figure 5 The thermal management system 50 shown in includes a refrigerant system 52 and a coolant system 54. In Figure 5 , the solid lines represent the coolant conduits and the dashed lines represent the refrigerant conduits. The refrigerant system 52 includes a compressor 56, a plurality of control valves shown as V1, V2, V3 and V4, a plurality of refrigerant check valves shown as CV1, CV2, CV3 and CV4, a plurality of expansion valves shown as EXV1, EXV2 and EXV3, an external heat exchanger 58, an internal evaporator 60 and an internal condenser 62. The control valves V1, V2, V3 and V4 can be simple on-off valves (e.g., solenoid valves). The external heat exchanger 58 can be similar to Figure 3A and Figure 3B The external heat exchanger 16 shown in. To achieve enhanced functionality (e.g., heating and defogging simultaneously), or for other reasons, an evaporator 60 and an internal condenser 62 can be provided to replace Figure 3A and Figure 3B The internal heat exchanger 20.

[0073] The coolant system 54 includes a first pump 64, a second pump 66, a plurality of control valves shown as 68a and 68b, a coolant check valve shown as 70, a high-pressure heater 71, and a radiator 72. A heat load may exist. In the case where the vehicle is an EV, the heat load may include, for example, a traction battery 74 and a traction motor 76 (including associated power electronics). A coolant-refrigerant heat exchanger 78 is provided for heat exchange between the coolant in the coolant system 54 and the refrigerant in the refrigerant system 52. The coolant-refrigerant heat exchanger 78 has a coolant flow path 78a therethrough and a refrigerant flow path 78b therethrough.

[0074] The operation of the thermal management system 50 is described as follows: The refrigerant system 52 can operate in more modes compared to the heat pump system 40 shown in Figure 3A and Figure 3B These modes include: a first mode for heating the passenger compartment 12 using heat from the coolant in the coolant system 54 via the coolant-refrigerant heat exchanger 78; a second mode for heating the passenger compartment 12 using heat from the coolant in the coolant system 54 and also using the external heat exchanger 58 as an evaporator; and a third mode for cooling the passenger compartment 12 using the external heat exchanger 58 as a condenser.

[0075] In the first mode, the control valves V1, V2, V3, and V4 are controlled to direct the refrigerant flow from the compressor 56 through the control valve V2 and through the internal condenser 62, where the refrigerant condenses and transfers heat to the internal air shown as 24 to heat the passenger compartment 12. The refrigerant passes from the internal condenser 62 through the check valve CV1. Downstream of the check valve CV1, the refrigerant flow may be directed through a first refrigerant flow path 80a through an optional refrigerant-refrigerant heat exchanger 80, through an expansion valve EXV3, through the coolant-refrigerant heat exchanger 78, back through a second refrigerant flow path 80b, through the refrigerant-refrigerant heat exchanger 80, and back to the inlet of the compressor 56. In the refrigerant-refrigerant heat exchanger 80, some heat is removed from the refrigerant in the first refrigerant flow path 80a to add heat to the refrigerant in the second refrigerant flow path 80b in order to further superheat the refrigerant in the second refrigerant flow path 80b to reduce the likelihood of any liquid refrigerant existing in the flow, which could damage the compressor 56 downstream thereof.

[0076] In the coolant - refrigerant heat exchanger 78, the refrigerant receives heat from the coolant flowing through it, thereby driving the evaporation of the refrigerant which is at a low pressure due to passing through the third expansion valve EXV3. The coolant can be heated by one or more of several sources. This includes the traction battery 74 and / or the traction motor 76 (and associated power electronics) and / or the high - voltage heater 71. More specifically, heat is generated during discharge and charging of the traction battery 74 and transferred to the coolant. Additionally, the traction motor 76 and associated power electronics generate heat during operation of the traction motor 76. However, in some cases, such as when starting the vehicle in very cold outside temperatures, the traction battery 74 and the traction motor 76 may not be hot enough to provide sufficient heat to the coolant to heat the refrigerant in the coolant - refrigerant heat exchanger 78. In such cases, the high - voltage heater 71 can be operated to heat the refrigerant so as to sufficiently heat the refrigerant in the coolant - refrigerant heat exchanger 78 to evaporate the refrigerant. The refrigerant then is transferred from the coolant - refrigerant heat exchanger 78 to the second refrigerant flow path 80b in the refrigerant - refrigerant heat exchanger 80, and from the second refrigerant flow path 80b to the inlet of the compressor 56.

[0077] Optionally, a receiver / dryer 97 is provided to remove contaminants such as oil, water, dust, and debris from the refrigerant, as these contaminants can damage components such as the compressor 56.

[0078] In the first mode described above, all of the refrigerant flows through the coolant - refrigerant heat exchanger 78. In the second operating mode, as described above, only the first portion of the refrigerant passes through the coolant - refrigerant heat exchanger 78, and the second portion of the refrigerant is transferred to the first expansion valve EXV1 where its pressure will be reduced. The second portion of the refrigerant travels from the first expansion valve EXV1 to the external heat exchanger 58 which will act as an evaporator in order to evaporate the second portion of the refrigerant. The evaporated refrigerant passes from the external heat exchanger 58 through the control valve V3, through the check valve CV3, and together with the first portion of the refrigerant through the second refrigerant flow path 80b in the refrigerant - refrigerant heat exchanger 80, and from the second refrigerant flow path 80b to the inlet of the compressor 56.

[0079] In a third operating mode for the thermal management system 50, the control valves V1, V2, V3, and V4 are controlled to direct refrigerant flow from the compressor 56 through the control valve V1, through the external heat exchanger 58 acting as a condenser, through the check valve CV2, through the first refrigerant flow path 80a passing through the refrigerant-refrigerant heat exchanger 80, through the second expansion valve EXV2 where the pressure of the refrigerant is reduced, and then through the internal evaporator 60 where the refrigerant is evaporated, thereby cooling the internal air 24 to cool the passenger compartment 12. The refrigerant passes from the internal evaporator 60 through the second refrigerant flow path 80b of the refrigerant-refrigerant heat exchanger 80 and is conveyed from the second refrigerant flow path 80b to the inlet of the compressor 56.

[0080] The thermal management system 50 is advantageous relative to Figure 3A and Figure 3B the heat pump system 40 shown in because the coolant-refrigerant heat exchanger 78 allows heat from the coolant to be used to assist in heating the refrigerant when such heat is available and / or beneficial.

[0081] Description of the structure of the novel coolant-refrigerant heat exchanger

[0082] Referring to Figures 6 to 10 , which shows a coolant-refrigerant heat exchanger 100 according to an embodiment of the present disclosure. Figure 6 is a perspective view of the coolant-refrigerant heat exchanger 100. FIGS. 7a and 7b together are an exploded perspective view of the coolant-refrigerant heat exchanger 100. Figure 8 is an enlarged perspective view of a part of the coolant-refrigerant heat exchanger 100. Figure 9 is a cross-sectional view of the coolant-refrigerant heat exchanger 100, and Figure 10 is a partially exploded perspective view of a part of the coolant-refrigerant heat exchanger 100.

[0083] The coolant-refrigerant heat exchanger 100 can be used in Figure 14for use in the electric vehicle 151 shown. The electric vehicle 151 can include a passenger compartment 12, a traction battery 74, and a traction motor 76 (the traction motor 76 being for driving one or more of the wheels shown at 99). The electric vehicle 151 can be any type of vehicle that employs a traction motor and a traction battery for supplying power to the traction motor. The electric vehicle 151 is shown as an SUV, but it can be a car, a light truck, a heavy truck, an off-road vehicle, a vehicle used in construction, an aircraft, or any other suitable type of vehicle. Additionally, the electric vehicle 151 can include only a traction motor (or a number of traction motors) for driving the movement of the electric vehicle 151, or alternatively, the electric vehicle 151 can include an internal combustion engine, such as a range extender engine, to assist in recharging the traction battery 74 when the traction battery 74 is depleted or nearly depleted. In yet another alternative embodiment, the electric vehicle 151 can be a fuel cell vehicle that generates electricity via a fuel cell for providing power to the traction motor 76.

[0084] It should be noted that the traction battery 74 shown in the figures is just one example of an energy source for the electric vehicle 151. In embodiments where the electric vehicle 151 is a fuel cell vehicle, the electric vehicle 151 includes a fuel cell stack and can also include a traction battery (although smaller than the batteries in a typical battery electric vehicle). The fuel cell stack and the traction battery (if one is provided) will constitute the energy source for the fuel cell vehicle. In the embodiments shown herein, the energy source is the traction battery that is connected to the traction motor to supply power to the traction motor.

[0085] The electric vehicle 151 can also include a thermal management system 150, which is described in more detail below with respect to Figures 13 to 22 The thermal management system 150 can include a coolant-refrigerant heat exchanger 100.

[0086] The coolant-refrigerant heat exchanger 100 includes a coolant flow path 102 ( Figure 10 ) for conveying coolant (represented by the arrow 104 in Figure 10 ) therethrough and a refrigerant flow path 106 ( Figure 10 and Figure 10 ) for conveying refrigerant (represented by the arrow 108 in Figure 11 ) therethrough. The coolant flow path 102 and the refrigerant flow path 106 are positioned to transfer heat from one of the coolant 104 and the refrigerant 108 to the other of the coolant 104 and the refrigerant 108. In the example shown, the coolant-refrigerant heat exchanger 100 includes a plurality of flow plates 110. Each flow plate 110 has FIGS. 7b and Figure 9The first face 112a, the second face 112b, and the peripheral edge face 114 of the flow plate (FIG. 7b) shown in. The plurality of flow plates 110 are connected together such that the coolant flow path 102 and the refrigerant flow path 106 are defined between the mutually facing faces of adjacent flow plates among the plurality of flow plates 110. More specifically, referring to Figure 9 and Figure 10 , in the illustrated embodiment, the coolant flow path 102 is defined between the second face 112b of the first plate (shown as 110a) and the first face 112a of the second plate (shown as 110b), between the second face 112b of the third plate (shown as 110c) and the first face 112a of the fourth plate (shown as 110d), between the second face 112b of the fifth plate (shown as 110e) and the first face 112a of the sixth plate (shown as 110f), and so on. Similarly, the refrigerant flow path 106 is defined between the first face 112a of the second flow plate 110b and the second face 112b of the third flow plate 110c, between the first face 112a of the fourth plate (shown as 110d) and the second face 112b of the fifth flow plate 110e, and so on. In the illustrated embodiment, there are 32 flow plates 110 sealed and joined together.

[0087] As can be seen in Figure 7A , in the illustrated embodiment, the peripheral edge face 114 of the flow plate 110 is a rectangle with rounded corners (a rounded rectangle). However, it should be understood that the peripheral edge face 114 of the flow plate can have any other suitable shape, such as a circular shape, an oval shape, a regular or irregular polygon shape with rounded corners having more or fewer than 4 sides, or any other suitable shape. The shape of the peripheral edge face 114 of the flow plate preferably has rounded corners where there are corners. However, corners that are substantially not rounded can alternatively be provided.

[0088] The flow plate 110 can be made of any suitable material, such as aluminum for example. Although aluminum is known to have higher thermal conductivity compared to certain materials, such as stainless steel, aluminum is not a typical material for coolant or refrigerant conduits in a coolant - refrigerant heat exchanger for a vehicle.

[0089] Figure 17 Illustrates an intermediate manufacturing state of the coolant - refrigerant heat exchanger 100. As in Figure 17As shown in, each of the flow plates 110 has a flange portion 230 for connecting the flow plates 110 together. The flange portions 230 of the flow plates 110 cooperate with each other. A brazing material can be provided between the flange portions 230, and then the flow plates 110 can be heated to melt the brazing material in order to connect the flow plates 110 together in a sealed manner. The outermost edge of the flange portion 230 is shown at 240. In some embodiments, the outermost edge 240 of the flange portion 230 has a shape that creates valleys 250 between the continuous flow plates in the flow plates 110 when the flow plates 110 are connected together in a sealed manner.

[0090] As shown in Figure 18 When connected together in a sealed manner, the flow plates 110 can form a flow plate assembly 252. Referring to FIG. 7a, in the illustrated embodiment, a first end cover plate 109 can be provided and the first end cover plate 109 can be connected to the first ends of the plurality of flow plates 110 in a sealed manner and thus can be included in the flow plate assembly 252. The first end cover plate 109 can include a refrigerant inlet 116a, a refrigerant outlet 116b, a coolant inlet 118a, and a coolant outlet 118b. The first end cover plate 109 can be connected to the flow plates 110 in the same manner as the flow plates 110 are connected to each other, and can be processed together with the flow plates to further form a heat exchange surface. A refrigerant filter 119 can be provided at the refrigerant inlet 116a to filter contaminants from the refrigerant 108 before the refrigerant passes through the flow plates 110.

[0091] A second end cover plate 111 ( Figure 9 ) can be provided and the second end cover plate 111 can be connected to the second ends of the plurality of flow plates 110 in a sealed manner and thus can be included in the flow plate assembly 252. The second end cover plate 111 can be connected to the flow plates 110 in the same manner as the flow plates 110 are connected to each other, and can be processed together with the flow plates to further form a heat exchange surface.

[0092] The flow plate assembly 252 has a first end face 254, a second end face 256, and a flow plate assembly peripheral edge face 258, which are discussed further below. The flow plate assembly peripheral edge face 258 itself can have any suitable shape. For example, the flow plate assembly peripheral edge face can include a plurality of side faces 258a and a plurality of corners 258b. The corners 258b can be large radius corners as shown, or they can be small radius corners. The flow plate assembly peripheral edge face 258 can include four side faces 258a and can be generally rectangular as shown, or it can have any other suitable number, less than or more than Figure 18The number of sides shown in the side view is side 258a. Additionally, as shown, side 258a does not need to be straight. Side 258a can have any other suitable shape.

[0093] Referring to FIGS. 7b and Figure 8 , each flow plate 110 in the flow plate 110 has a plurality of ridges 120 on each of its first side 112a and second side 112b, and the plurality of ridges 120 define grooves, which optionally serve as channels for the flow of refrigerant 108 or coolant 104. In the illustrated embodiment, the ridges 120 on each flow plate 110 form a pattern that alternates with the pattern of the ridges 120 on each adjacent flow plate 110. In other words, the ridges on the odd-numbered flow plates 110 (i.e., the first plate, the third plate, the fifth plate, etc.) form a pattern that alternates with the pattern on the even-numbered flow plates 110 (i.e., the second plate, the fourth plate, the sixth plate, etc.). The pattern of the ridges 120 on both the odd-numbered flow plates 110 and the even-numbered flow plates 110 can be a chevron pattern.

[0094] Figure 9 A cross-sectional view of the coolant-refrigerant heat exchanger 100 is shown. As can be seen, the flow plate 110 has a first refrigerant through-hole and a second refrigerant through-hole 113, and a first coolant through-hole and a second coolant through-hole 115. The space between the first flow plate 110a and the second flow plate 110b is the first coolant space 121. The space between the second flow plate 110b and the third flow plate 110c is the first refrigerant space 123. The space between the third flow plate 110c and the fourth flow plate 110d is the second coolant space 121, and so on. The space between the fourth flow plate 110d and the fifth flow plate 110e is the second refrigerant space 123. In the entire series of flow plates 110, the spaces between the flow plates 110 alternate between the coolant space 121 and the refrigerant space 123. As can be seen, in the region of the refrigerant through-hole 113, the first flow plate 110a is sealingly engaged with the second flow plate 110b, the second flow plate 110b is spaced apart from the third flow plate 110c, the third flow plate 110c is sealingly engaged with the fourth flow plate 110d, and the fourth flow plate 110d is spaced apart from the fifth flow plate 110e, and so on. Therefore, the refrigerant 108 can flow in the refrigerant space 123. Additionally, in the region of the coolant through-hole 115, the first flow plate 110a is spaced apart from the second flow plate 110b, the second flow plate 110b is sealingly engaged with the third flow plate 110c, the third flow plate 110c is spaced apart from the fourth flow plate 110d, and the fourth flow plate 110d is sealingly engaged with the fifth flow plate 110e, and so on. Therefore, the coolant 104 can flow in the coolant space 121.

[0095] The coolant - refrigerant heat exchanger 100 further includes an auxiliary heater 122 that is positioned to heat both the refrigerant 108 and the coolant 104 when located within the coolant - refrigerant heat exchanger 100. The auxiliary heater 122 can be an induction heater and thus can include an induction coil 260 that extends in a selected path and is positioned adjacent to the flow plate such that the induction coil can be energized to heat the flow plate by induction.

[0096] The auxiliary heater 122 can also include any suitable driver circuit for generating an oscillating current in the induction coil 260. The driver circuit can be an electronic oscillator that draws current from a DC power source such as the traction battery 74 or from an auxiliary battery (not shown) having a voltage lower than the traction battery 74 and converts the current to AC. Alternatively, the driver circuit can be powered by an AC power source, such as a power source that itself draws power from the traction battery 74 or from the aforementioned optionally provided auxiliary battery and converts the current to AC. The driver circuit can generate any suitable type of wave in the current, such as a sine wave, a square wave, or a triangular wave. The driver circuit can be provided as part of the coolant - refrigerant heat exchanger 100 or can be provided separately from the coolant - refrigerant heat exchanger 100.

[0097] As shown in Figures 19 to 31 the induction coil 260 can surround a plurality of flow plates 110. In the embodiment shown in Figure 19 the induction coil 260 surrounds the peripheral edge surface 258 of the flow plate assembly. However, in an alternative embodiment, the induction coil 260 can surround the plurality of flow plates 110 in another manner, such as by extending along the first end face 254 and the second end face 256 and spanning the top and bottom portions of the peripheral edge surface 258 of the flow plate assembly.

[0098] In Figure 19 and Figure 20 the embodiment shown, the induction coil 260 is mounted in direct contact with the peripheral edge surface 258 of the flow plate assembly. Since the peripheral edge surface 258 of the flow plate assembly can have valleys 250, such as those shown in Figure 17 the valleys 250 cause at least a portion of the peripheral edge surface 258 of the flow plate assembly to be spaced apart from the induction coil 260. It should be noted that this spacing between the peripheral edge surface 258 of the flow plate assembly and the induction coil 260 does not increase any risk of damage to the induction coil 260 or the flow plate assembly 252. This is because induction heating does not require direct contact between the heater and the element to be heated, unlike a thin - film heater that may require such contact to eliminate the possibility of hot spots in the heater and subsequent damage caused by those hot spots.

[0099] The induction coil 260 includes an electrical conductor 262, which can be made of any suitable conductive material such as copper. In Figure 19 and Figure 20 In the illustrated embodiment, the electrical conductor 262 is encapsulated in an electrical insulation sheath 264 to prevent current from conducting from the electrical conductor 262 into the flow plate 110. The electrical insulation sheath 264 can be made of any suitable material. For example, the electrical insulation sheath 264 can be made of fiberglass or a suitable polymer. In other embodiments, the electrical insulation sheath 264 is not required.

[0100] In the illustrated embodiment, the induction coil 260 extends helically around the peripheral edge surface 258 of the flow plate assembly. As shown in Figure 19 and Figure 20 The induction coil 260 includes a plurality of annular members 266 that can optionally be held spaced apart from each other. However, alternatively, the annular members 266 of the induction coil 260 can be positioned in contact with each other, particularly in embodiments where the electrical insulation sheath 264 is provided.

[0101] In the illustrated embodiment, the induction coil 260 can be connected to a suitable source that generates an oscillating current in the induction coil 260, which in turn directly generates heat in the flow plate 110 via induction.

[0102] Referring to Figure 21 , which shows another embodiment. In Figure 21 The coolant-refrigerant heat exchanger 100 also includes an internal thermal insulation layer 268 that surrounds the peripheral edge surface 258 of the flow plate assembly and is surrounded by the induction coil 260. The internal thermal insulation layer 268 can be made of a non-conductive material. Thus, the induction coil 260 can generate heat in the flow plate 110 via induction through the internal thermal insulation layer 266 with a relatively small loss of efficiency. Examples of materials from which the thermal insulation layer can be made include polymer foams, fiberglass, solid polymer materials, and / or aerogel materials. Any other suitable material can be used. The internal thermal insulation layer 268 inhibits heat leakage from the flow plate 110, which improves the efficiency of the coolant-refrigerant heat exchanger 100 in transferring heat to the coolant and / or refrigerant passing through it. The induction coil 260 preferably includes both the electrical conductor 262 and the electrical insulation sheath 264. However, in theory, the electrical insulation sheath 264 can be omitted from the induction coil 260. In such an embodiment, the annular members 266 are positioned spaced apart from each other to prevent accidental conduction between the sides of the annular members 266. The internal thermal insulation layer 268 also helps to inhibit the electrical insulation sheath 264 from being heated by the heated flow plate 110, thereby protecting the electrical insulation sheath 264 from possible damage.

[0103] Reference Figure 22 , which shows another embodiment. In Figure 22 , the coolant - refrigerant heat exchanger 100 further includes an internal thermal insulation layer 268 that surrounds the peripheral edge surface 258 of the flow plate assembly and is surrounded by the induction coil 260, and the coolant - refrigerant heat exchanger 100 further includes an external thermal insulation layer 270. The internal thermal insulation layer 268 and the external thermal insulation layer 270 can be made of non - conductive materials. As in the embodiment in Figure 21 , the induction coil 260 can generate heat in the flow plate 110 with a relatively small efficiency loss via induction through the internal thermal insulation layer 266, while the internal thermal insulation layer 267 inhibits heat leakage from the flow plate 110, and the external thermal insulation layer 270 further inhibits heat leakage from the flow plate 110.

[0104] Reference Figure 23 , which shows another embodiment. In Figure 23 , the coolant - refrigerant heat exchanger 100 further includes a carrier 272 that includes at least one conductor groove 274 for holding the induction coil 260. In the illustrated embodiment, the carrier 272 can be made of any suitable material, such as an electrically insulating material, such as a non - conductive polymer, cellulose, fiberglass, glass, or any other suitable material. Thus, the induction coil 260 can include an electrical conductor 262 and the electrical insulation sheath 264 can be omitted. Although in the illustrated embodiment, a plurality of smaller grooves 274 are shown in the carrier 272, the plurality of smaller grooves 274 can be replaced by a single helically extending groove. The carrier 272 can also be made of a thermally insulating material and can thus be referred to as an internal thermal insulation layer. Thus, it can be said that the internal thermal insulation layer includes at least one conductor groove 274 for holding the induction coil 260.

[0105] The carrier 272 surrounds the peripheral edge surface 258 of the flow plate assembly and is surrounded by the induction coil 260 (and held via at least one conductor groove 274).

[0106] Reference Figure 24 and Figure 25 , which shows another embodiment. In Figure 23 , the coolant - refrigerant heat exchanger 100 further includes at least one pedestal 276 positioned between the peripheral edge surface 258 of the flow plate assembly and the induction coil 260. In the illustrated embodiment, there are a plurality of pedestals 276. For example, four pedestals 276 can be provided, which engage each side surface 258a of the peripheral edge surface 258 of the flow plate assembly.

[0107] The flow plate 110 has a first magnetic permeability and at least one base 276 has a second magnetic permeability greater than the first magnetic permeability. Thus, the base 276 can have an improved ability to convert electromagnetic energy from the induction coil 260 into heat compared to the flow plate 110 itself. This is because in addition to generating heat through eddy currents, the induction coil can also generate heat in the base 276 through hysteresis (due to its greater magnetic permeability). In contrast, due to the low magnetic permeability of the flow plate 110 in embodiments where it is made of a low magnetic permeability material such as aluminum, the induction coil 260 does not generate a significant amount of heat in the flow plate 110 via hysteresis. An example of a suitable material for the base 276 is ferritic steel. However, any other suitable material can be used. For example, the base 276 can be made of any suitable material containing iron.

[0108] At least one base 276 is positioned to be inductively heated by the induction coil 260 and is at least indirectly engaged with the flow plate assembly 252 so as to heat the flow plate assembly 252 by heat conduction. The base 276 can be engaged with the peripheral edge surface 258 of the flow plate assembly by a thermally conductive epoxy resin, glue, or some suitable adhesive layer. Alternatively, the base 276 can be engaged with the peripheral edge surface 258 of the flow plate assembly by mechanically holding the engagement, such as by a plurality of strips, clamps, or other mechanical elements that push or pull the base 276 into engagement with the peripheral edge surface 258 of the flow plate assembly.

[0109] In the illustrated embodiment, each of the bases 276 engages each of the side surfaces 258a of the peripheral edge surface 258 of the flow plate assembly. However, each of the bases 276 can engage any suitable portion of the peripheral edge surface 258 of the flow plate assembly.

[0110] Due to the presence of the base 276, at least in embodiments where the base 276 absorbs most of the electromagnetic energy from the induction coil 260, the induction coil 260 heats the base 276 and the base 276 in turn heats the flow plate 110.

[0111] Additionally, it should be noted that in embodiments where the base is made of steel and the flow plate 110 is made of aluminum, the base retains heat for a longer period of time compared to aluminum. Thus, the induction coil 260 can be turned off while the base 276 continues to heat the flow plate 110 and thus continues to impart heat to the coolant and / or refrigerant contained in the flow plate 110.

[0112] Refer to Figure 26 , which shows another embodiment. In Figure 26In [the context], the coolant-refrigerant heat exchanger 100 further includes an internal thermal insulation layer 268 that surrounds the peripheral edge surface 258 of the flow plate assembly, is positioned outside at least one base 276, and is surrounded by the induction coil 260. In this embodiment, the internal thermal insulation layer 268 is non-conductive as in other embodiments, and thus the induction coil 260 heats at least one base 276 through the internal thermal insulation layer 268. In another embodiment, the coolant-refrigerant heat exchanger 100 may further include an external thermal insulation layer 270 that achieves an effect similar to that provided by the external thermal insulation layer 270 in the other embodiments shown and described.

[0113] It should be noted that in any case where the term "base" is used, it is for the purpose of improving readability. It should be noted that in any statement made herein, unless it is a statement that necessarily and obviously requires the existence of multiple bases 276, the term "base" can be replaced by "at least one base".

[0114] Referring to Figure 27 , which shows another embodiment that is similar to Figure 25 and Figure 25 the embodiment shown in [the reference], but in this embodiment, a plurality of bases 276 are provided, and the plurality of bases 276 do not extend beyond the side surface 258a of the peripheral edge surface 258 of the flow plate assembly and the plurality of bases 276 are chamfered (at the chamfer 278) to reduce the abruptness of the bent portion of the induction coil 260.

[0115] Referring to Figure 28 , which shows another embodiment that is similar to Figure 27 the embodiment shown in [the reference], but in this embodiment, a carrier 272 is provided, and the carrier 272 surrounds the peripheral edge surface 258 of the flow plate assembly and is surrounded by the induction coil 260 (and is held via at least one conductor groove 274). The carrier 272 can be as described in [the reference] (for example, in terms of material properties), with the difference that Figure 23 in [the reference] the carrier 272 is positioned between at least one base 276 and the induction coil 260. Figure 28

[0116] Referring to Figure 29 , which shows another embodiment that may be similar to Figure 26The embodiment shown in [reference], but in this embodiment, at least one base 276 includes a first C-shaped base 276a and a second C-shaped base 276b. The first C-shaped base 276a and the second C-shaped base 276b together at least partially surround the peripheral edge surface 258 of the flow plate assembly. In the embodiment shown, the first C-shaped base 276a and the second C-shaped base 276b each have a first free end and a second free end shown at 280 and 282 respectively, such that the first free ends 280 of the first C-shaped base 276a and the second C-shaped base 276b are spaced apart from each other by a first gap G1, and the second free ends 282 of the first C-shaped base 276a and the second C-shaped base 276b are spaced apart from each other by a second gap G2. The first gap G1 and the second gap G2 are set to ensure that the first C-shaped base 276a and the second C-shaped base 276b do not interfere with each other during installation onto the flow plate assembly 252, to ensure good contact between the opposing inner surfaces of the first C-shaped base 276a and the second C-shaped base 276b shown at 284 and the mating side 258a of the peripheral edge surface 258 of the flow plate assembly. The first C-shaped base 276a and the second C-shaped base 276b may originally be, for example, in terms of material properties, as described in the embodiment regarding Figure 25 and Figure 25 in the embodiment shown.

[0117] In other embodiments incorporating at least one base 276, the first C-shaped base 276a and the second C-shaped base 276b may be held in engagement with the peripheral edge surface 258 of the flow plate assembly by a thermally conductive epoxy, glue, or some suitable adhesive layer.

[0118] Referring to Figure 30 and Figure 31 , which shows another embodiment that may be similar to the embodiment shown in Figure 28 and includes at least one base, the at least one base being a first C-shaped base 276a and a second C-shaped base 276b, but in this embodiment, the first C-shaped base 276a and the second C-shaped base 276b together include at least one conductor groove 274. Since the conductor groove 274 is directly provided in the at least one base 276, a separate carrier for holding the induction coil 260 is not required. However, it should be understood that the induction coil 260 will include an electrical insulation sheath 264 to prevent electrical conduction into the first C-shaped base 276a and the second C-shaped base 276b. Additionally, since the electrical insulation sheath 264 is in direct contact with the first C-shaped base 276a and the second C-shaped base 276b, the electrical insulation sheath 264 will be made of a material that can withstand the heat generated in the first C-shaped base 276a and the second C-shaped base 276b.

[0119] In Figure 31In [the figure], the thermally conductive epoxy layer, glue, or some suitable adhesive layer is shown at 285.

[0120] In Figure 31 , multiple flow plates 110 are shown as a single element, although the cross-sectional view shown will pass through the thickness of several of the flow plates 110.

[0121] Referring to Figure 32 and Figure 33 which shows another embodiment that may be similar to the embodiment shown in Figure 28 and includes at least one base 276 that is positioned to be inductively heated by an induction coil 260, and the at least one base 276 is at least indirectly engaged with the flow plate assembly 252 to heat the flow plate assembly 252 by heat conduction.

[0122] In the embodiment shown, the flow plate assembly 252 includes at least one base aperture 286 that extends through at least some of the flow plates 110. At least one base 276 is positioned within at least one base aperture 286. In the embodiment shown, the at least one base 276 includes four bases 276, although any suitable number of bases 276 may be used. In the embodiment shown, each of the bases 276 is tubular. However, alternatively, each base 276 may be a solid rod. In the embodiment shown, each of the bases 276 is cylindrical. However, alternatively, each base 276 may have other shapes, such as a rectangular prism.

[0123] In Figure 33 , multiple flow plates 110 are shown as a single element, although the cross-sectional view shown will pass through the thickness of several of the flow plates 110.

[0124] Figure 32 and Figure 33 The material properties of at least one base 276 in the embodiments shown in

[0125] Referring to Figure 34 and Figure 35 which shows another embodiment that may be similar to the embodiments shown in Figure 32 and Figure 33 and includes at least one base 276 that is positioned to be inductively heated by an induction coil 260 and the at least one base 276 is at least indirectly engaged with the flow plate assembly 252 to heat the flow plate assembly 252. In the embodiment shown, at least one base 276 is positioned within at least one base aperture 286, asFigure 32 and Figure 33 as in the embodiments shown in Figure 33 . In the embodiments shown, at least one base 276 includes four bases 276, and each of the four bases 276 is associated with Figure 32 and Figure 33 at least one base 276 in Figure 33 can be cylindrical (or any other suitable shape) and tubular (or solid). However, in Figure 34 and Figure 35 the embodiments shown in Figure 35 , the coolant - refrigerant heat exchanger 100 includes a plurality of induction coils 260 instead of one induction coil 260, and each induction coil 260 has an associated one of at least one base 276 and heats an associated one of at least one base 276. In the embodiments shown, each induction coil 260 extends inside an associated one of at least one base 276.

[0126] It should be noted that Figure 35 certain elements are omitted so as not to obscure other elements. For example, one of the base apertures 286 is shown without a base therein, however, during operation, there will be a base 276 in this base aperture 286.

[0127] In any of the embodiments described herein, it should be understood that if at least one base 276 is provided, an internal thermal insulation layer 268 can be provided at some position between the induction coil 260 and at least one base 276, or if no base is provided, the internal thermal insulation layer 268 can be provided at some position between the induction coil 260 and the flow plate assembly 252.

[0128] It should be noted that at least one base 276 in each of the embodiments has been described as having a greater magnetic permeability than the flow plate 110 in order to generate heat via hysteresis. However, it should also be noted that at least one base 276 can also have a greater electrical resistivity than the flow plate 110. A material with a higher resistivity is heated more due to inductance compared to a material with a lower resistivity. Thus, at least one base 276 made of a certain type of steel can have a higher resistivity than the flow plate 110 made of aluminum, and thus can be heated better by the induction coil 260 compared to the flow plate 260 in the embodiments in Figure 19 Figure 19 , and in Figure 19In the embodiments, the induction coil 260 directly heats the flow plate 110 (wherein, the flow plate 110 is made of a low resistivity material such as aluminum). In some embodiments, at least one base 276 can be made of a material that has a resistivity relatively higher than that of the flow plate 110 and does not necessarily have a magnetic permeability higher than that of the flow plate 110. However, in the preferred embodiments, at least one base 276 is made of a material that has both a magnetic permeability and a resistivity higher than those of the flow plate 110.

[0129] In other words, induction heating is caused by one or both of the following: heating by generating eddy currents in the body to be heated (e.g., the flow plate 110 and / or the base 276); and heating by generating hysteresis in the body to be heated (e.g., in the base 276). In a non-magnetic material such as aluminum, heating occurs only by generating eddy currents. In a material that is ferrite, such as certain types of steel, heating can occur by both generating eddy currents and generating hysteresis. Due to the relatively high resistivity in steel, the heating that occurs only by generating eddy currents may be greater in steel than in aluminum. Additionally, heating generated by hysteresis exists in ferritic steel but not in aluminum.

[0130] Although one or more induction coils 260 have been shown wound helically around an axis to surround an element such as a flow plate assembly or surrounded by an element such as a base 476, it should be noted that the induction coil 260 can be an electric trace that is disposed in a plane on a substrate or in a plate in a generally helical arrangement but is a self-supporting element that is not printed on the substrate. Such induction coils are currently provided in some induction cooktops. One or more such induction coils can be positioned on each side 258a of the peripheral edge surface 258 of the flow plate assembly to heat the flow plate 110 or one or more bases 276 positioned to heat the flow plate 110.

[0131] Although at least one base 276 has been provided to assist in heating the flow plate 110, it should also be noted that at least one protective base can be used to divert magnetic flux lines from any element to be protected, such as any electronic component of the coolant-refrigerant heat exchanger 100. Such an embodiment can employ at least one protective base that is located outside the induction coil 260 and can have an external thermal insulation layer 280 positioned outside of it. The element to be protected, such as the aforementioned electronic device, can be positioned outside of the external thermal insulation layer 280. The protective base will ensure that no magnetic field will extend beyond itself, thereby ensuring that no induction heating of the aforementioned electronic device (or any other element to be protected) will occur.

[0132] It should be noted that the use of the induction coil 260 to heat the flow plate assembly 252 is particularly advantageous in high wattage applications, such as in larger thermal management systems for large vehicles such as buses. It should also be noted that the use of the induction coil 260 can be applied to heat exchangers that do not convey both refrigerant and coolant and do not perform heat exchange between the two fluids. For example, in at least some embodiments, the induction coil 260 can be used on a container that carries only one fluid, such as only refrigerant or only coolant. Such a container can be similar to a coolant-refrigerant heat exchanger, but can include only two ports instead of four ports, and such a container can be formed of a plurality of flow plates similar to the flow plate 110 or can have some other suitable structure.

[0133] In addition to the induction coil 260 described above, the auxiliary heater 122 can include: a first end heater 122b that engages with the first flow plate 110a to impart heat through the thickness of the first flow plate 110a to the plurality of flow plates 110; and a second end heater 122c that imparts heat through the thickness of the second end cover plate 111 to the plurality of flow plates 110. A heat dissipation plate 125 can be provided between the second end heater 122c and the second end cover plate 111. The first end heater 122b and the second end heater 122c can each employ a helical-shaped induction coil as described above.

[0134] The auxiliary heater 122 is characterized in that it is sized to evaporate all of the refrigerant (i.e., all of the refrigerant 108 in the refrigerant flow path 106) in the refrigerant 108 passing through the coolant-refrigerant heat exchanger 100, so as to ensure that substantially all of the refrigerant 108 in the coolant-refrigerant heat exchanger 100 can be evaporated without any heat being input from the coolant 104 in the coolant flow path 102 to the refrigerant 108. In some embodiments, the auxiliary heater 122 is sized to superheat all of the refrigerant in the refrigerant flow path 106 to ensure that all of the refrigerant 108 is evaporated and substantially no refrigerant 108 remains in its liquid phase.

[0135] A controller 124 can be provided to control the operation of the auxiliary heater 122. Electrical connectors shown at 126 and 128 are provided for supplying power to the auxiliary heater 122 and for supplying power to the controller 124.

[0136] A heat exchanger housing 130 may be provided for accommodating the above components. The housing 130 may include a first housing portion 130a and a second housing portion 130b sealingly connected to the first housing portion 130a. An O-ring 132 may be provided for sealing around an orifice shown at 134 in the housing 130, which orifice allows the coolant inlet 118a, the coolant outlet 118b, the refrigerant inlet 116a, and the refrigerant outlet 116b to pass through. Another sealing member 136 is provided between the refrigerant filter 119 and the refrigerant inlet 116a.

[0137] Figure 11 is shown Figures 6 to 10 A schematic illustration of the layout of the coolant space 121 and the refrigerant space 123 and the coolant flow path 102 and the refrigerant flow path 106 in the embodiment shown in. As can be seen, the coolant 104 travels from the coolant inlet 118a through the coolant space 121, and then travels along the coolant space 121 and returns to the coolant outlet 118b. Similarly, the refrigerant 108 travels from the refrigerant inlet 116a through the refrigerant space 123, and then travels along the refrigerant space 123 and returns to the refrigerant outlet 116b. Thus, in Figure 11 (and Figures 6 to 10 ) the embodiment shown, both the coolant outlet 118b and the refrigerant outlet 116b are located at the same end of the plurality of flow plates 110 as the coolant inlet 118a and the refrigerant inlet 116a. In Figure 12 the alternative embodiment shown, the first end cover plate 109 and the second end cover plate 111 are configured to each have one inlet and one outlet. For example, the first end cover plate 109 may have the coolant inlet 118a and the refrigerant outlet 116b, and the second end cover plate 111 may have the coolant outlet 118b and the refrigerant inlet 116a. Thus, the coolant 104 may flow from the first end through the flow plates 110 to the second end, and the refrigerant 108 may flow from the second end through the flow plates 110 to the first end.

[0138] Regardless of whether the coolant flow path 102 and the refrigerant flow path 106 are as shown in Figures 6 to 11 or as shown in Figure 12 , the coolant flow path 102 and the refrigerant flow path 106 can be said to be positioned to transfer heat from one of the coolant 104 and the refrigerant 108 to the other of the coolant 104 and the refrigerant 108, and the auxiliary heater 122 can be said to be positioned to heat both the refrigerant 108 and the coolant 104 in the coolant-refrigerant heat exchanger 100.

[0139] Several advantageous features of the coolant - refrigerant heat exchanger 100 are described below: The coolant - refrigerant heat exchanger 100 includes a plurality of flow plates 110. It has been found that providing an auxiliary heater 122 in the form of a strip heater 122a that extends along substantially all of the peripheral edges of the flow plates 110, and also providing a first end heater 122b and a second end heater 122c, enables efficient heat transfer through the height, width, and thickness of the flow plates 110. The peripheral edge heater 122a and the first end heater 122b and the second end heater 122c can be solid elements formed from sheet material that is joined to the flow plates 110 in any suitable manner, such as by a suitable adhesive, or joined to the first end cover plate 109 and the second end cover plate 111 respectively. In some embodiments, the peripheral edge heater 122a and one or more of the first and second end heaters can be in the form of a thin - film heater that is directly printed onto the surface intended to receive the heat transfer.

[0140] Description of the layout of a thermal management system incorporating a novel coolant - refrigerant heat exchanger

[0141] Referring Figure 13 , which shows a thermal management system 150 for an electric vehicle according to an embodiment of the present disclosure. The electric vehicle is shown at Figure 14 151.

[0142] The thermal management system 150 can have a layout similar to the thermal management system 50 shown in Figure 5 , and can have a refrigerant system 152 and a coolant system 154. Some differences between the thermal management system 150 and the thermal management system 50 are described below. One difference is that Figure 5The high-pressure heater 71 and its associated coolant conduits are not necessary and are omitted from the thermal management system 150. Additionally, the coolant system 154 includes a battery loop 154a and a motor loop 154b that are connected to each other through a first transfer conduit 156 and a second transfer conduit 158. The coolant system 154 also includes additional three-way valves relative to the coolant system 54 of the thermal management system 50. Thus, the coolant system 154 has a first three-way valve 160, a second three-way valve 162, and a third three-way valve 164, and also has a battery loop pump 166 and a motor loop pump 168. Additionally, the coolant system 154 also includes a coolant check valve 169 located on the second transfer conduit 157. Additionally, the coolant system 154 includes a battery loop bypass conduit 158 and a motor loop bypass conduit 159 that do not exist in the coolant system 54. The arrangement of the refrigerant system 152 can be similar to the arrangement of the refrigerant system 52. Although specific configurations for the coolant system 154 and the refrigerant system 152 are shown, and although specific types of valves (e.g., on-off type control valves, three-way valves, and check valves) are shown, it should be noted that the coolant system 154 and the refrigerant system can be configured differently. As a simple example, the three-way valves 160, 162, and 164 can be replaced with multiple on-off type valves. Another simple example is that the check valves in both the refrigerant system 154 and the coolant system 152 can also be replaced with on-off type control valves. Additionally, the control valves V1, V2, V3, and V4 and their associated refrigerant conduits can be replaced with conduits having different numbers of valves, including different arrangements including, for example, one or more three-way valves.

[0143] A control system shown at 170 can be provided for controlling the operation of the thermal management system 150. The control system 170 can include a PCB (printed circuit board) 170a on which a processor 170b and a memory 170c are present. The control system 170 can be said to be operatively connected to the control valves V1, V2, V3, and V4, the expansion valves EXV1, EXV2, and EXV3, the three-way valves 160, 162, and 164, and the auxiliary heater 122 to control their operation. In Figure 13 lines representing wires showing the connection between the PCB 170a and the aforementioned valves and the auxiliary heater are not shown so as not to make the figures more difficult to understand. Additionally, the control system 170 can include several sensors such as a cabin temperature sensor 172, a refrigerant temperature sensor 174 at the refrigerant inlet 116a of the coolant-refrigerant heat exchanger 100, and an auxiliary heater temperature sensor 176, all of which are connected to the PCB 170a to respectively transfer signals related to the air temperature in the passenger cabin 12, the refrigerant temperature at the refrigerant inlet 116a of the coolant-refrigerant heat exchanger 100, and the temperature of the auxiliary heater 122 to the processor 170b.

[0144] It should be noted that the control system 170 does not need to include only a single PCB 170a, a processor 170b, and a memory 170c. Alternatively, the control system 170 can include multiple PCBs at various locations in the electric vehicle 151, each of the multiple PCBs having one or more processors and memories. For example, the PCB 170a can be just a part of the control system 170 and can be a part of the ECM (electronic control module) for the electric vehicle 151, which controls the operation of many subsystems in the electric vehicle 151. The control system 170 can also include a controller 124 in the coolant-refrigerant heat exchanger 100. Communication between the PCB 170a and the controller 124 can occur via a wired connection or can occur via a wireless connection.

[0145] In addition, any one of the temperature sensors 172, 174, and 176 does not have to be directly connected to the PCB 170a or communicate directly with the PCB 170a. For example, the auxiliary heater temperature sensor 176 can communicate directly with the controller 124, and the controller 124 can in turn pass the information to the PCB 170a.

[0146] A significant difference between the thermal management system 150 and the thermal management system 50 is that the thermal management system 150 includes a coolant-refrigerant heat exchanger 100 instead of a coolant-refrigerant heat exchanger 78.

[0147] Description of the thermal management system in the cabin heating mode using the auxiliary heater

[0148] Figure 13 The thermal management system 150 in the cabin heating mode using the auxiliary heater 122 is shown. In this mode, the control valves V1, V3, and V4 are closed, while the control valve V2 is open, and the expansion valves EXV1 and EXV2 are closed, while the expansion valve EXV3 is open.

[0149] Figure 13 The mode shown in can be used when starting the vehicle when the ambient temperature is below -15 degrees Celsius. In this case, it is desirable to operate the refrigerant system 152 to heat the passenger cabin 12. Therefore, the refrigerant 108 will flow through the internal condenser 62 to heat the internal air 24 of the passenger cabin 12. However, the operation of the external heat exchanger 58 as an evaporator may be undesirable because there is a risk of ice formation on the external heat exchanger 58 when heat is drawn from the ambient air 22 into the external heat exchanger 58 according to the humidity level of the ambient air 22, which will impede its operation.

[0150] Accordingly, it is desirable to use the coolant - refrigerant heat exchanger 100 as an evaporator. However, the coolant 104 is below - 15 degrees Celsius, and neither the traction battery 74 nor the traction motor 76 is warm enough to provide sufficient heat to the coolant 104 for use in the coolant - refrigerant heat exchanger 100 to drive the evaporation of the refrigerant 108. Additionally, the three - way valves 160 and 162 can be positioned to isolate the battery circuit 154a from the motor circuit 154b and bypass the coolant - refrigerant heat exchanger 100 to allow the traction battery 74 to quickly warm up to its optimal operating temperature.

[0151] Additionally, in some cases, the ambient temperature may be low enough such that the pressure of the refrigerant 108 is less than 1 atmosphere. For example, if one examines Figure 15 the pressure - enthalpy diagram associated with the refrigerant 108 used in the thermal management system 150 as shown, it can be seen that when the temperature of the refrigerant is below approximately - 30 degrees Celsius, the pressure of the refrigerant 108 drops below 1 atmosphere. Thus, during operation of the compressor 56 in such an environment, since the pressure at the inlet of the compressor 56 is less than the ambient pressure outside the refrigerant system 152, contaminants may be drawn into the refrigerant system 152. Such contaminants can include particles, moisture, or any other type of contaminant. Such contaminants can be harmful to the compressor 56 and can, in any case, reduce the performance of the refrigerant system.

[0152] In such a case, the control system 170 operates the coolant - refrigerant heat exchanger 100 in an only - auxiliary - heating mode, in which the auxiliary heater 122 causes substantially all of the refrigerant 108 in the refrigerant flow path 106 to evaporate without any heat input from the coolant 104 in the coolant flow path 102. In some embodiments, the auxiliary heater 122 is heated to a sufficient temperature to superheat the refrigerant 108 to ensure that substantially all of the refrigerant 108 is evaporated and substantially no refrigerant 108 remains in its liquid phase.

[0153] Accordingly, by providing the auxiliary heater 122 (FIG. 7b, Figure 8 ), a sufficient amount of heat can be imparted to the refrigerant 108 in the coolant - refrigerant heat exchanger 100 to raise the temperature of the refrigerant 108 above a threshold temperature at which the refrigerant 108 has a pressure of 1 atmosphere.

[0154] Figure 13The operating modes shown are merely examples of the sole auxiliary heating mode for the thermal management system 150, in which the auxiliary heater 122 causes the refrigerant 108 in the refrigerant flow path 106 to evaporate without any heat input from the coolant 104 in the coolant flow path 102. When the control system 170 operates the thermal management system 150 in the mode shown in Figure 13 the control system 170 can be said to operate the coolant-refrigerant heat exchanger 100 and can be said to be programmed to operate the coolant-refrigerant heat exchanger 100 in the sole auxiliary heating mode, in which the auxiliary heater 122 causes the refrigerant 108 in the refrigerant flow path 106 to evaporate without any heat input from the coolant 104 in the coolant flow path 102.

[0155] Description of the modified pressure-enthalpy diagram

[0156] Referring to Figure 15 , the dashed curve shown at 180 represents the change in the properties of the refrigerant 108 as it passes through the Figure 13 refrigerant system 152 shown. Point 182 represents the properties of the refrigerant immediately upstream of the compressor 14 after the refrigerant 108 has been heated by the auxiliary heater 122 for some time. As can be seen, the temperature of the refrigerant 108 at point 182 is higher than the aforementioned threshold temperature. Accordingly, the pressure of the refrigerant 108 at point 182 is higher than 1 atmosphere, thereby preventing contaminants from entering the refrigerant system 152. Curve segment 180a represents the change in the properties of the refrigerant 108 due to the operation of the compressor 56. Point 184 represents the properties of the refrigerant 108 downstream of the compressor 56 and upstream of the internal condenser 62. As can be seen, both the pressure and temperature of the refrigerant 108 increase between point 182 and point 184.

[0157] Curve segment 180b represents the change in the properties of the refrigerant 108 due to the operation of the internal condenser 62. Point 186 represents the properties of the refrigerant 108 immediately downstream of the internal condenser 62 (and thus upstream of the expansion valve (when the thermal management system 150 is operating in the mode shown in Figure 13 the expansion valve is the expansion valve EXV3)). As can be seen, the temperature of the refrigerant 108 decreases and then remains constant during the phase change in the internal condenser 62.

[0158] Curve segment 180c represents the change in the properties of the refrigerant due to the expansion valve (e.g., when the thermal management system 150 is operating in Figure 13The change in the properties of the refrigerant 108 caused by operating the expansion valve EXV3) in the mode shown. Point 188 represents the properties of the refrigerant 108 immediately downstream of the expansion valve (and thus upstream of the coolant-refrigerant heat exchanger 100). As can be seen, the pressure and temperature of the refrigerant 108 decrease due to passing through the expansion valve.

[0159] The curve segment 30d represents the change in the properties of the refrigerant 108 caused by passing through the coolant-refrigerant heat exchanger 100. After passing through the coolant-refrigerant heat exchanger 100, the refrigerant 108 returns to point 182, which represents the properties of the refrigerant 108 immediately downstream of the coolant-refrigerant heat exchanger 100 and thus upstream of the compressor 56. As can be seen, the pressure and temperature remain substantially constant in the coolant-refrigerant heat exchanger 100 until the refrigerant reaches the boundary line shown at 189, which represents the boundary between the liquid and gas phases. As Figure 15 shown, the auxiliary heater 122 transfers sufficient heat to the refrigerant 108 after all of the refrigerant has been vaporized in the coolant-refrigerant heat exchanger 100 to superheat the refrigerant 108 by a certain amount, thereby driving a small increase in the temperature of the refrigerant 108. This ensures that all of the refrigerant leaves the coolant-refrigerant heat exchanger 100 as a gas.

[0160] When operating in the Figure 13 mode shown, it should be noted that once the refrigerant 108 has been heated by the coolant-refrigerant heat exchanger 100 and is in a steady state cycle after the aforementioned threshold temperature, the curve 180 is the curve of the refrigerant 108. To reach this steady state cycle from a state where the refrigerant 108 is initially at a temperature below the aforementioned threshold temperature, the thermal management system 150 can operate in the Figure 13 mode shown for a period of time to circulate the refrigerant 108 through the coolant-refrigerant heat exchanger 100 (and the compressor 56, the internal condenser 62, and the expansion valve EXV3) in order to gradually heat the refrigerant 108. At some point during the gradual heating of the refrigerant 108, the refrigerant 108 will develop from a state where the pressure of the refrigerant 108 at the point immediately upstream of the compressor 56 is less than 1 atmosphere to a state where the pressure of the refrigerant 108 at the point immediately upstream of the compressor 56 is greater than 1 atmosphere. In Figure 15 this is graphically represented upstream of the compressor 56, from the state where the pressure of the refrigerant 108 is less than 1 atmosphere to the state where its pressure is greater than 1 atmosphere. As Figure 15As can be seen, a dashed curve 190 is shown representing the changes in the properties (temperature and pressure) of the refrigerant 108 that occur in the absence of the auxiliary heater 122. Thus, when the vehicle is started in a cold ambient temperature, the initial state of the refrigerant 108 at the inlet of the compressor 56 is shown at point 192. Initially, when the refrigerant system 152 operates, the compressor 56 brings the refrigerant 108 to the point shown at 194 (the change in properties is represented by the curve segment 190a). The refrigerant 108 then passes through the condenser 162, in which the refrigerant 108 is cooled and condensed, which is represented by the curve segment 190b. Downstream of the internal condenser 62, the refrigerant properties are shown at point 196. The refrigerant 108 then passes through an expansion valve (e.g., expansion valve EXV3), in which the pressure of the refrigerant 108 is reduced, thereby reducing its temperature, which is represented by the curve segment 190c. Downstream of the expansion valve, the refrigerant properties are shown at point 198. Point 198, although shown as being at the same pressure as point 192, does not need to be precisely at the same pressure as point 192. The refrigerant 108 then passes through the coolant-refrigerant heat exchanger 100, in which the refrigerant 108 undergoes a phase change and is superheated by a certain amount, thereby increasing its temperature by a certain amount and thus also increasing its pressure. The curve segment 190d represents the change in the properties of the refrigerant 108 that occurs during the phase change (i.e., evaporation) that takes place in the coolant-refrigerant heat exchanger 100. After the phase change is completed in the coolant-refrigerant heat exchanger 100, the superheating of the refrigerant 108 in the coolant-refrigerant heat exchanger 100 is represented by the curve segment 199.

[0161] If the auxiliary heater 122 is powerful enough, when the refrigerant 108 exits the coolant-refrigerant heat exchanger 100 (as represented by Figure 15 the curve segment 199 in), a single cycle through the refrigerant system 152 can bring the refrigerant 108 to the state represented by point 182. However, the jump in the temperature and pressure of the refrigerant 108 may be less when the refrigerant 108 passes through the coolant-refrigerant heat exchanger 108 than Figure 15 that shown in. In other words, the length of the curve segment 199 may be less than Figure 15The length shown in [figure]. However, over time, after multiple cycles (i.e., after multiple passes through the refrigerant system 152), the temperature of the refrigerant 108 at the inlet of the compressor 56 will gradually increase until the pressure of the refrigerant 108 at the inlet of the compressor 56 finally rises above 1 atmosphere. In other words, there will eventually be a point at which the refrigerant 108 will have a pressure below 1 atmosphere, and the refrigerant 108 will complete passing through the refrigerant system (i.e., through the compressor 56, the internal condenser 62, the expansion valve EXV3, and the coolant-refrigerant heat exchanger 100), whereby the superheat occurring in the coolant-refrigerant heat exchanger 100 will cause the refrigerant 108 to leave the coolant-refrigerant heat exchanger 100 at a pressure greater than 1 atmosphere. In other words, this transition in pressure from below 1 atmosphere to above 1 atmosphere can be said to occur by a method of the refrigerant system 152 that includes:

[0162] a) Compressing the refrigerant 108 in the refrigerant system 152, whereby the refrigerant 108 is changed from a first temperature and a first pressure (point 192) to a second temperature and a second pressure (point 194), wherein the first temperature is low enough such that the first pressure is less than 1 atmosphere;

[0163] b) Condensing the refrigerant 108 after step a), whereby the refrigerant 108 is changed from the second temperature and the second pressure (point 194) to a third temperature and a third pressure (point 196);

[0164] c) Passing the refrigerant 108 through an expansion valve after step b), whereby the refrigerant 108 is changed from the third temperature and the third pressure (point 196) to a fourth temperature and a fourth pressure (point 198);

[0165] d) After step c), evaporating the refrigerant 108 in the evaporator of the coolant-refrigerant heat exchanger 100, wherein the coolant-refrigerant heat exchanger 100 is positioned to transfer heat between the coolant 104 in the coolant system 154 and the refrigerant 108, wherein the evaporation is carried out by heating the refrigerant 108 using the auxiliary heater 122 without using the coolant-refrigerant heat exchanger 100 to heat the refrigerant 108, so that the refrigerant 108 is changed from the fourth temperature and the fourth pressure (point 198) to a fifth temperature and a fifth pressure (point 182), wherein the fifth temperature is high enough such that the fifth pressure is greater than 1 atmosphere; and

[0166] e) Compressing the refrigerant 108 after step d), whereby the refrigerant 108 is changed from the fifth temperature and the fifth pressure (point 182) to a temperature higher than the fifth temperature and a pressure higher than the fifth pressure (point 184).

[0167] Although it is advantageous to increase the pressure of the refrigerant 108 from a pressure below 1 atmosphere to a pressure above 1 atmosphere, it should also be noted that in any case, even if the pressure of the refrigerant 108 remains below 1 atmosphere, an increase in the pressure of the refrigerant 108 is still advantageous because it increases the density and thus increases the mass flow rate of the refrigerant 108, thereby increasing the effectiveness of the ability of the refrigerant system 152 to perform heat exchange. Accordingly, the above method can be more generally stated such that the first pressure of the refrigerant 108 can be any suitable pressure, which can be above or below one atmosphere, and such that the fifth pressure (point 182) can be any suitable pressure, provided that it is greater than the first pressure of the refrigerant 108 (point 192).

[0168] Description of a first algorithm for controlling the operation of an auxiliary heater

[0169] The auxiliary heater 122 can be controlled by the control system 170 using any suitable algorithm. For example, a suitable method for controlling the auxiliary heater 122 is shown at 200 in Figure 16 The method 200 begins at 202. At step 204, it is determined whether the thermal management system 150 is in a mode in which the auxiliary heater 122 will be used (such as for example Figure 13the pattern shown in). If not, the control loop returns to this determination step 204 until the moment when the thermal management system 150 is in a suitable mode. Once it is determined that the thermal management system 100 is in a suitable mode, step 206 is executed. Step 206 is used to determine whether the temperature of the passenger compartment 12 is lower than any temperature set by the vehicle occupants (referred to herein as the target compartment temperature). This step includes the control system 170 receiving data from the compartment temperature sensor 172. If the passenger compartment 12 is already at or above its target compartment temperature, the control system 170 sets the auxiliary heater 122 to "off" at step 208. The target compartment temperature can be any suitable value, such as 20 degrees Celsius shown in step 206. If the passenger compartment 12 is below its target compartment temperature, step 210 is executed. Step 210 is used to determine whether the temperature of the auxiliary heater 122 is lower than the upper threshold temperature (the upper threshold temperature is the highest temperature at which the auxiliary heater 122 is allowed to operate). This step includes the control system 170 receiving data from the auxiliary heater temperature sensor 176. The upper threshold temperature can be any suitable temperature, such as, for example, 120 degrees Celsius. If the auxiliary heater 122 is already at or above its upper threshold temperature, the control system 170 executes step 212. Step 212 is used to set the auxiliary heater 122 to "on" at a power level lower than the power level at which it was turned on immediately before executing step 212. After executing step 210 or step 212, the control returns to step 206. If the auxiliary heater 122 is determined to be lower than its upper threshold temperature, step 214 is executed. Step 214 is used to set the auxiliary heater 122 to "on" at any suitable power level (such as full power), and return the control to step 206.

[0170] Although the descriptions contained herein constitute various embodiments of the present invention, it should be understood that the present invention can be further modified and changed without departing from the fair meaning of the appended claims.

[0171] Item list

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Claims

1. A coolant-refrigerant heat exchanger for a thermal management system used in an electric vehicle, comprising: a plurality of flow plates, each of the flow plates having a plurality of faces and a peripheral edge, wherein the plurality of flow plates are sealingly joined together to define a coolant flow path through the coolant-refrigerant heat exchanger and a refrigerant flow path through the coolant-refrigerant heat exchanger, wherein the coolant flow path and the refrigerant flow path are positioned to transfer heat from one of the coolant and the refrigerant to the other of the coolant and the refrigerant, wherein the flow plates are made of a conductive material; and an auxiliary heater positioned to heat both the refrigerant and the coolant in the coolant-refrigerant heat exchanger, wherein the auxiliary heater includes an induction coil positioned adjacent to the flow plates and capable of being energized to inductively heat the flow plates.

2. The coolant-refrigerant heat exchanger according to claim 1, wherein, the induction coil surrounds the plurality of flow plates.

3. The coolant-refrigerant heat exchanger according to claim 1, wherein, each of the flow plates has a first face, a second face, and a flow plate peripheral edge face, and the plurality of flow plates together form a flow plate assembly having a first end face, a second end face, and a flow plate assembly peripheral edge face, wherein the induction coil surrounds the flow plate assembly peripheral edge face.

4. The coolant-refrigerant heat exchanger according to claim 3, wherein, the flow plate assembly peripheral edge face has a plurality of valleys that space at least a portion of the flow plate assembly peripheral edge face from the induction coil.

5. The coolant-refrigerant heat exchanger according to claim 3, wherein, the induction coil extends helically around the flow plate assembly peripheral edge face.

6. The coolant-refrigerant heat exchanger according to claim 5, further comprising an internal thermal insulation layer that surrounds the flow plate assembly peripheral edge face and is surrounded by the induction coil.

7. The coolant-refrigerant heat exchanger according to claim 6, wherein, the internal thermal insulation layer includes at least one conductor groove for holding the induction coil.

8. The coolant-refrigerant heat exchanger according to claim 6, further comprising an external thermal insulation layer that surrounds the induction coil.

9. The coolant-refrigerant heat exchanger according to claim 1, wherein, the induction coil includes an electrical conductor encapsulated in an electrical insulation sheath.

10. The coolant-refrigerant heat exchanger according to claim 3, further comprising at least one base positioned between the flow plate assembly peripheral edge face and the induction coil, wherein, the flow plate has a first magnetic permeability and at least one of the bases has a second magnetic permeability greater than the first magnetic permeability.

11. The coolant-refrigerant heat exchanger according to claim 10, wherein, the flow plate is made of aluminum and the base contains iron.

12. The coolant - refrigerant heat exchanger according to claim 10, wherein, at least one of the bases surrounds the flow plate assembly.

13. The coolant - refrigerant heat exchanger according to claim 12, wherein, the coolant - refrigerant heat exchanger further includes an internal thermal insulation layer that surrounds the peripheral edge surface of the flow plate assembly, is positioned outside at least one of the bases, and is surrounded by the induction coil.

14. The coolant - refrigerant heat exchanger according to claim 10, wherein, the peripheral edge surface of the flow plate assembly includes a plurality of side surfaces and a plurality of corners located between the side surfaces, wherein at least one of the bases includes a base on each of the plurality of side surfaces.

15. The coolant - refrigerant heat exchanger according to claim 10, wherein, the peripheral edge surface of the flow plate assembly is substantially rectangular, and wherein at least one of the bases includes a first C - shaped base and a second C - shaped base, and wherein the first C - shaped base and the second C - shaped base together at least partially surround the peripheral edge surface of the flow plate assembly.

16. The coolant - refrigerant heat exchanger according to claim 10, wherein, at least one of the bases includes at least one conductor groove for holding the induction coil.

17. The coolant - refrigerant heat exchanger according to claim 10, further comprising at least one base that is positioned to be inductively heated by the induction coil, and the base is at least indirectly engaged with the flow plate assembly so as to heat the flow plate assembly by heat conduction, wherein, the flow plate has a first magnetic permeability and the base has a second magnetic permeability greater than the first magnetic permeability, wherein the flow plate assembly includes at least one base aperture that extends through at least some of the flow plates of the flow plate, and wherein at least one of the bases is positioned in the at least one base aperture.

18. The coolant - refrigerant heat exchanger according to claim 5, further comprising a carrier that surrounds the peripheral edge surface of the flow plate assembly and is surrounded by the induction coil, wherein, the carrier includes at least one conductor groove for holding the induction coil.

19. The coolant - refrigerant heat exchanger according to claim 1, further comprising at least one base that is positioned to be inductively heated by the induction coil, and the base is at least indirectly engaged with the flow plate assembly so as to heat the flow plate assembly by heat conduction, wherein, the flow plate has a first magnetic permeability and the base has a second magnetic permeability greater than the first magnetic permeability, wherein the flow plate assembly includes at least one base aperture that extends through some of the flow plates of the flow plate, and wherein at least one of the bases is positioned in the at least one base aperture, and wherein the induction coil is positioned inside one of at least one of the bases.

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