Serpentine counterflow cooling plate for vehicle battery modules

Abstract

The present invention provides a battery module or battery pack having a serpentine counterflow cooling plate having improved dissipation of heat from individual battery cells, wherein the cooling plate provides a more uniform temperature gradient across the cooling plate to more uniformly transfer heat from the battery cells to a liquid coolant circulating through the cooling plate. The cooling plate selectively omits turbulator material upstream of the turbulator to control and manage the coolant fed into and through the turbulator, thereby providing a more uniform temperature gradient across the cooling surface.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 767,224 filed on November 14, 2018, the disclosure of which is incorporated herein by reference in its entirety. Technical Field

[0003] The present invention relates to a vehicle battery module or battery pack having a plurality of battery cells, and more particularly to a cooling plate for cooling the battery cells during operation. Background Art

[0004] Electric vehicles are typically powered by at least one battery module or battery pack that incorporates a plurality of battery cells disposed adjacent to one another. During operation, the charging and discharging of the battery cells may generate heat, which in excess may adversely affect battery performance and life. Therefore, known battery modules may include cooling devices to transfer and dissipate heat from the battery cells, thereby maintaining a stable operating temperature of the battery. Such cooling devices include heat exchangers of various configurations, one type of heat exchanger being a cooling plate that is liquid-cooled and has a plate-like configuration that is positioned adjacent to a plurality of batteries to extract heat therefrom. A liquid coolant (which may preferably be a 50 / 50 WEG coolant or another suitable fluid that transfers heat) is then circulated between the cooling plate and a cooling system (such as a vehicle's cooling system). As the coolant circulates through the cooling plate, the coolant extracts heat from the battery module and dissipates the heat through the vehicle cooling system or other similar cooling system.

[0005] While cooling plates are commonly used to remove heat from battery modules, it is an object of the present invention to provide an improved cooling plate that provides more uniform removal of heat from each battery cell to avoid significant differences in temperature within the individual batteries. Summary of the invention

[0006] The present invention relates to a battery module or battery pack of the present invention having improved dissipation of heat from individual battery cells, and also to an improved cooling plate that provides a more uniform temperature gradient across the top and bottom cooling surfaces of the cooling plate to more uniformly transfer heat from the battery cells to a liquid coolant circulating through the cooling plate. The improved temperature gradient provides a more uniform removal of heat from each of the individual battery cells, which can provide improved battery performance and battery life and other advantages associated with these features.

[0007] The cooling plate of the present invention generally has a plate-like configuration that is face-enlarged on the opposite side surfaces of the cooling plate. These side surfaces define cooling surfaces and can contact and support one or more and preferably a large number of battery cells that are arranged adjacent to each other on the corresponding cooling surfaces. In a preferred embodiment, a group of battery cells is connected to each of the cooling surfaces so that the cooling plate is used to cool two groups of battery cells. The combination of the cooling plate and one or more groups of battery cells is typically assembled together by a suitable support structure or material to form an integrated battery module that can be used for electric vehicles. It should be understood that the present invention was developed for electric vehicles, but the inventive concepts disclosed herein can be used for cooling plates and battery modules provided for other types of battery-powered electrical equipment.

[0008] In more detail, the cooling plate includes an open interior that is subdivided into internal coolant channels extending between an inlet and an outlet to absorb heat from the cooling surface. The coolant channels are formed in a pattern defined by a plurality of channel segments that form a serpentine countercurrent path through the cooling plate, which provides improved dissipation of heat from the individual battery cells. In this regard, the cooling plate provides a more uniform temperature gradient across the cooling plate to more evenly transfer heat from the battery cells to the liquid coolant circulating through the cooling plate.

[0009] The cooling channel includes a plurality of channel segments defining a serpentine counterflow pattern, which preferably has four paths, i.e., flow paths extending along four parallel channel segments. As the coolant flows along the tortuous path, the coolant receives heat from each or both of the cooling surfaces to absorb and remove heat from each battery cell. In a preferred mode, the coldest channel segment is located at the inlet and is positioned adjacent to and parallel to the warmest channel segment at the outlet, which allows two adjacent and parallel coolant channels to exchange heat and provide a more uniform temperature gradient.

[0010] In one aspect, portions of the cooling channels include turbulators or fins that increase the heat transfer between the cooling surface and the coolant. The turbulators increase the heat transfer from the surface of the cooling plate to the fluid by increasing the amount of surface area of ​​the coolant in contact with the highly thermally conductive aluminum and also creating a greater turbulence or tortuous path that breaks up the boundary layer. In order to reduce the temperature gradient over the entire surface of the cooling plate, the cooling effect of the cold incoming coolant is reduced. In order to reduce this cooling power, the turbulators are removed from the first portion of the flow path, which reduces the heat transfer from the surface to the coolant. This results in the surface above and below the turbulator-free area being warmer than the surface in the case where there are turbulators therein, thereby reducing the difference in surface temperature compared to the directly adjacent countercurrent path, because the coolant in the adjacent countercurrent path is at a farther downstream location, so that the coolant has absorbed more heat. In order to achieve a more uniform temperature gradient, the cooling plate of the present invention also has an improved coolant flow, particularly the coolant flow starting from the inlet before entering the first turbulator. Most preferably, the inlet leads to a channel section upstream of the turbulator, wherein the upstream channel section does not have a turbulator, which reduces the heat transfer coefficient in this area, thereby reducing the temperature difference between the warmest outlet area and the coldest inlet area. This also allows the fluid flow to be less restricted and less turbulent along this channel section compared to the flow through the turbulator. This allows for faster and less turbulent flow in the relatively cold inlet area. This arrangement further improves the temperature gradient over the cooling surface, wherein the cooling plate selectively omits the turbulator material in a portion of the coolant channel upstream of the turbulator.

[0011] Other goals and objectives of the present invention and variations thereof will become apparent upon reading the following description and examining the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a perspective view of a battery module taken from the upper right front corner showing a first group of battery cells and a second group of battery cells coupled to opposing cooling surfaces of a cooling plate.

[0013] Figure 2 is a perspective view of a battery module taken from the lower right front corner showing a first group of battery cells and a second group of battery cells coupled to opposing cooling surfaces of a cooling plate.

[0014] Figure 3 is a perspective view of a battery module taken from the upper right rear corner showing a first group of battery cells and a second group of battery cells coupled to opposing cooling surfaces of a cooling plate.

[0015] Figure 4 is a bottom view of the cooling plate.

[0016] Figure 5 is a side perspective view of the cooling plate.

[0017] Figure 6 is a top cross-sectional view of the cooling plate.

[0018] Figure 7 is an enlarged partial view of the inlet port of the cooling plate.

[0019] Figure 8 is along Figure 4 Front cross-sectional view of the cooling plate taken along line 8-8.

[0020] Fig. 9 is along Figure 4 A side cross-sectional view of the cooling plate taken along line 9-9.

[0021] Fig.10 is a partial enlarged perspective view of a section of a turbulator disposed within a cooling plate.

[0022] Fig.11 is a top cross-sectional view of a second embodiment of a cooling plate of the present invention.

[0023] Fig.12 is a bottom perspective view from the side of a third embodiment of a cooling plate of the present invention.

[0024] Fig.13 yes Fig.13 A bottom cross-sectional view of a cooling plate schematically showing the locations of the inlet and outlet in dashed outline.

[0025] Certain terminology will be used in the following description for convenience and reference only and will not be limiting. For example, the words "upwardly," "downwardly," "rightwardly," and "leftwardly" will refer to directions in the accompanying drawings, which directions are used as references. The words "inwardly" and "outwardly" will refer to directions toward and away from, respectively, the geometric center of the arrangement and designated parts thereof. The terminology will include the words specifically mentioned, derivatives thereof, and words of similar meanings. DETAILED DESCRIPTION

[0026] See also Figure 1 , the battery module 10 or battery pack of the present invention is shown as having a configuration that provides improved dissipation of heat from the individual battery cells 12. The battery module 10 includes an improved cooling plate 14 that provides a more uniform temperature gradient across the length and width of the cooling plate 14 to more evenly transfer heat from the battery cells 12 to the liquid coolant circulating through the cooling plate 14. The improved temperature gradient provides more uniform removal of heat from each of the individual battery cells 12, which can provide improved battery performance and battery life, as well as other advantages associated with these features.

[0027] refer to Figures 1 to 3 In more detail, the cooling plate 14 of the present invention generally has a plate-like configuration that is presented as face-enlarging on opposite side surfaces of the cooling plate 14. These side surfaces define a first cooling surface 15 and a second cooling surface 16, which are preferably substantially planar and preferably completely flat below the battery and facing in opposite directions from each other. In the orientation shown, the first cooling surface 15 and the second cooling surface 16 may be referred to as an upper cooling surface and a lower cooling surface, but the battery module 10 may be oriented in a variety of orientations, so that the terms "upper" and "lower" are not limited to a specific vertical or horizontal orientation.

[0028] As in Figure 4 and Figure 5 As best seen in , the first cooling surface and the second cooling surface can be formed and are preferably formed to be substantially planar and extend across a substantial portion of the length and width of the cooling plate 14. In a preferred configuration, the cooling plate 14 is generally formed as a rectangle with a length that is longer than the width, but the length and width can also be made close to each other to resemble a more square shape. In addition, the peripheral edges 17A, 17B, 17C and 17D generally extend linearly in the longitudinal direction or the lateral direction, but the specific shape can be non-linear, provided that the cooling plate 14 is performed according to the present disclosure. In addition, the peripheral edge 17D at one end of the cooling plate 14 includes a clearance notch therein, but the specific formation of such edge 17D can vary.

[0029] See again Figure 1 and Figure 2 As shown, the cooling plate 14 is generally hollow and includes an inlet port 21 and an outlet port 22 near the edge 17D. The inlet port 21 and the outlet port 22 are configured to be connected to a cooling system (such as a cooling system for a vehicle) and form a part of the cooling system. The inlet port 21 and the outlet port 22 serve as connectors that are interconnected with other components of the cooling system and are configured to receive and discharge coolant (preferably liquid coolant) into and out of the cooling plate 14. In operation, the coolant circulates between the cooling plate 14 and other components of the cooling system (such as a cooling system of a vehicle). When the coolant circulates through the cooling plate 14, the coolant receives the heat generated in the battery module 10 for subsequent dissipation by the vehicle cooling system or other similar cooling systems. As described herein, the cooling plate 14 is configured to provide a more uniform removal of heat to avoid significant differences in temperature and reduce temperature gradients over the entire area of ​​the cooling surfaces 15 and 16.

[0030] See also Figures 1 to 3, each cooling surface 15 and / or 16 is configured to be coupled to one or more battery cells 23 disposed on the corresponding cooling surface 15 or 16. In a preferred embodiment, a plurality of battery cells 23 are coupled to each of the cooling surfaces 15 and 16, such that the cooling plate 14 is used to cool a first group of battery cells 24 and a second group of battery cells 25. The components of the cooling plate 14 and one or more groups of battery cells 24 and / or 25 are typically assembled together by a suitable support structure or material such as support panels 26 and 27 to form an integrated battery module 10 that can be used in various types of electrical devices, including electric vehicles. It should be understood that the present invention was developed for electric vehicles, but the inventive concepts disclosed herein can be used in other types of battery-powered electrical equipment.

[0031] Preferably, the cooling plate 14 includes a first group 24 of battery cells 23 coupled to the cooling surface 15 and a second group 25 of battery cells 23 coupled to the opposing cooling surface 16. In this way, the heat generated in each battery cell 23 is drawn to the cooling plate 14, which acts as a heat sink. A suitable thermal interface material (TIM) may be used to bond the battery cells 23 to the cooling surfaces 15 and 16 and facilitate the transfer of heat from each battery cell 23 to the cooling plate 14 during heat generation. As described above, the coolant then receives or draws this heat throughout the thickness of the cooling surfaces 15 and 16 for subsequent cooling by the cooling system. As described below, the cooling plate 14 is configured to provide improved cooling over the entire area of ​​each cooling surface 15 and 16 to dissipate heat more evenly, reduce temperature gradients across the length and width of the cooling surfaces 15 and 16, and thereby reduce the formation of hot zones within the groups 24 and 25 of battery cells 23.

[0032] Usually see Figure 5 and Figure 6 , Figure 5 is a side perspective view of the cooling plate 14 , with the internal structure shown in dashed outline to illustrate the flow path through the cooling plate 14 . Figure 6 is a top cross-sectional view of the cooling plate 14 showing the internal structure in greater detail, as will be further described below.

[0033] Next go to Figures 7 and 8 The cooling plate 14 can be formed of different configurations, but is preferably formed of a lower or bottom shell plate 28 that is substantially planar or flat to form the second cooling surface 16 and an upper or top shell plate 29 that is formed, such as by stamping, to form the first cooling surface 15. The lower shell plate 28 and the upper shell plate 29 have respective peripheral edges 28A and 29A that abut together, such as at Figure 7 Best seen in and also in Figure 8 and Fig. 9The peripheral edges 28A and 29A are secured and sealed together, such as by brazing or other fastening processes, with an interior chamber 30 formed within the assembled lower and upper shell panels 28, 29. Thus, the interior chamber 30 is defined between the lower and upper shell panels 28, 29 and is bounded or surrounded by the peripheral edges 28A and 29A.

[0034] Although the interior chamber 30 generally conforms to substantially the entire area of ​​the cooling plate 14, the interior chamber 30 is subdivided into multi-path interior coolant channels 31 extending between the inlet port 21 and the outlet port 22 to absorb heat from the cooling surfaces 15 and 16. The coolant channels 31 are formed in a multi-path pattern defined by a plurality of channel segments 32-38 that flow with each other to form a serpentine counter-flow pattern through the interior chamber 30 of the cooling plate 14.

[0035] In order to form the channel segments 32 to 38 and generate turbulence within portions of the coolant channels 31, inserts 39A and 39B including trapezoidal and rectangular portions are installed within the interior chamber 30 to subdivide the interior chamber 30 into the respective channel segments 32 to 38 of the coolant channels 31. Preferably, the inserts 39A and 39B are formed of a turbulator material so that the inserts 39A and 39B function as turbulator inserts or turbulators along selected portions of the coolant channels 31. Fig.10 There is shown a section 40 of one form of turbulator material configured with a pattern commonly referred to as slotted offset fins. The inserts 39A and 39B form an insert arrangement which may be formed from a plurality of structural components or even as a single piece.

[0036] In such as Fig.10 In the slotted offset fin turbulator seen in FIG. 4 , the turbulator segment 40 is composed of a hat-shaped fin 40A, which includes a fin wall 40B, which defines a channel 40C, which is generally longitudinally aligned to define a primary flow direction 41 in which fluid can most easily flow through the turbulator segment 40. Preferably, the turbulator segment 40 is formed from a one-piece flat metal sheet that is rolled by a forming machine that produces the slotted offset fin 40A. It can be seen that the fin 40A is offset, which still allows flow in the primary flow direction 41, but also defines a side channel 40D that allows fluid to enter the flow channel 40C laterally from a secondary flow direction 42. The secondary flow direction 42 is impeded to a greater extent than the primary flow direction 41, but the fluid is still able to enter the fin 40A from the secondary flow direction 42 and then be redirected to the primary flow direction 41. This feature facilitates flow through the insert 39A, as described in more detail herein.

[0037] See also Figure 5 and Figure 6 , the interior chamber 30 is subdivided by channel walls 45, 46 and 47 to define channel sections 32, 33 and 34. The first channel wall 45 begins with a stamped inlet wall section 48 formed by the shell plate 29. The inlet wall section 48 forms a short inlet channel 48A that is fed by coolant received from the inlet port 21 and supplies the coolant to the first channel section 32.

[0038] The first channel wall 45 extends nearly the length of the interior chamber 30 and joins the second channel wall 46 to form a right-angle turn, such that the first channel segment 32 supplies coolant downstream to the second channel segment 33. In turn, the third channel wall 47 extends along nearly most, but not all, of the length of the cooling plate to form the third channel segment 34, which leads downstream to the fourth channel segment 35, which in turn acts as a manifold to supply the fifth channel segment 36. Thus, the first channel segment 32 and the third channel segment 34 extend along opposite side edges of the cooling plate 14 and are oriented parallel to each other.

[0039] To form the fifth and sixth channel segments 36 and 37, the central channel wall 49 extends back along a portion of the length of the cooling plate 14 toward the peripheral edge 17B so that a turbulator region is formed wherein the fifth channel segment 36 flows downstream into the sixth channel segment 37. In turn, the sixth channel segment 37 flows into the seventh channel segment 38 which extends back along the central channel wall 49 and terminates at the outlet port 22 so that coolant can be discharged from the cooling plate 14 and returned to the cooling system for cooling and recirculation back to the inlet port 21.

[0040] As in Figure 5 and Figure 6As seen in FIG. 1 , the outlet reservoir 51 is formed adjacent to the outlet port 22 to receive the absorbed heat coolant from the seventh channel segment 38 and to collect the coolant to the outlet port 22. Notably, the first to seventh channel segments 32 to 38 define a serpentine counterflow pattern having a plurality of path segments (i.e., flow paths along the channel segments 32, 33, 34, 35, 36, 37, and 38). As the coolant flows along this tortuous path, the coolant receives heat from each or both of the cooling surfaces 15 and 16 to absorb and remove heat from each battery cell 23. In this pattern, the coldest channel segment 32 at the inlet port 21 is adjacent to and parallel to the warmest channel segment 38 at the outlet port 22, which provides a more uniform temperature gradient in this area of ​​the cooling plate 14. Heat transfer between the inlet channel segment 32 and the outlet channel segment 38 is minimal. However, the placement of the turbulators defined by the inserts 39A and 39B results in a more uniform temperature gradient. As discussed below, not having turbulators in the channel sections 32, 33, 34, and 35 reduces the heat transfer efficiency to ensure that the battery cells 12 in contact with this portion of the cooling plate are not "too cold." The turbulators in the subsequent channel sections 36, 37, and 38 improve the heat transfer efficiency in these areas and allow the battery cells 12 in contact with these channel sections 36, 37, and 38 to be cooled to a temperature similar to that of the battery cells 12 in contact with the channel sections 32, 33, 34, and 35. In addition, the interior area of ​​the cooling plate 14 has a similar temperature gradient because the channel sections 36, 37, and 38 capture more heat than the inlet channel sections 32, 33, 34, and 35. It is worth noting that the channel sections 36, 37, and 38 do not necessarily all capture more heat than the inlet channel sections 32, 33, 34, and 35. In contrast, the placement of the turbulator material defined by inserts 39A and 39B is responsible for the uniform temperature gradient. Technically, the temperature gradient at the inlet region will be relatively high, and the temperature gradient at the outlet region will be slightly lower, since the temperature of the coolant at inlet port 21 is the coldest and the temperature at outlet port 22 is the hottest.

[0041] The amount of heat transferred from the cooling surfaces 15 and 16 to the coolant is also affected by the flow rate and turbulence throughout the coolant channel 31. In this regard, three turbulator material sections are provided in the channel sections 36, 37 and 38 (see Fig.10 ), wherein the three turbulator material sections include a first turbulator 53 in the fifth channel section 36, a second turbulator 54 in the sixth channel section 37, and a third turbulator 55 in the seventh channel section 38, which are aligned end to end and are in fluid communication with each other. These turbulators 53, 54 and 55 are preferably composed of Fig.10 A slotted fin turbulator pattern is formed in which the main flow direction 41 is oriented at right angles to form a U-shaped flow pattern.

[0042] In order to facilitate the fluid flow, the second turbulator 54 located in the sixth channel section 37 is cut into a trapezoidal shape so as to have an angled end edge 57 with a side edge 58 extending therebetween. In this way, the fluid flow in the upstream turbulator 53 in the main flow direction 41 can most easily flow into the angled end edge 57 and redirected to the main flow direction 41 of the trapezoidal turbulator 54, as indicated by reference arrow 60. Since the trapezoidal turbulator 54 also receives flow from the secondary flow direction 42, additional flow (as indicated by reference arrow 61) is received through the side edge 58 of the trapezoidal turbulator 54, which is redirected to the main flow direction 41. It is worth noting that the secondary flow direction 42 has a greater flow resistance, that is, it is more difficult for the coolant to flow into the trapezoidal area from the straight side edge 58 of the trapezoidal area, but not through the angled end edge 57, which promotes the coolant to flow along the main flow direction 41 and prevents the occurrence of hot spots due to having a lack area along the cooling plate / flow path.

[0043] The trapezoidal turbulator 54 is discharged in a similar manner, with the flow in the primary flow direction 41 being turned as indicated by arrow 62 to subsequently flow through the exit turbulator 55 in its primary flow direction 41. Additionally, the coolant flow exits the trapezoidal turbulator 54 through the side edge 58 in the secondary flow direction 42 and follows a flow path indicated by arrow 63. The net effect of the three turbulators 53, 54 and 55 is to create turbulence and flow resistance that facilitates heat transfer into the coolant.

[0044] To improve heat transfer into the coolant, the cooling plate 14 of the present invention also has improved coolant flow, especially coolant flow starting from the inlet port 21 until entering the first turbulator 53. In this regard, the inlet port 21 preferably has a smaller resistance to fluid flow than the resistance to flow created by the turbulators 53, 54 and 55. Most preferably, the inlet port 21 leads to the first channel section 32, wherein the first channel section 32 is unrestricted and allows the fluid to flow freely along the channel section 32. The walls of the channel section 32 are relatively smooth to facilitate flow through it. The inlet has the coldest incoming fluid. Since there is no turbulator in the inlet section, the cold fluid is "less effective", wherein it is preferred that the cooling plate 14 is not as cold in this inlet section as when the turbulator is present to allow for more uniform temperature differences. The absence of turbulators or turbulator materials increases the thermal resistance in these areas. This arrangement reduces thermal efficiency at the inlet port 21 and in those channel sections 32 to 35 that do not have turbulators, and increases thermal efficiency in subsequent channels 36 to 38 that have turbulators. This reduced thermal efficiency is achieved by omitting turbulator or fin material at the inlet port 21 and preferably along the length of the inlet channel section 32. In addition, turbulator or fin material may also be omitted from subsequent downstream channel sections 33, 34, and even 35 to facilitate laminar fluid flow to remove heat transfer at a relatively low rate, thereby avoiding excessive cooling from the inlet coolant so that the temperature gradient between the coolant and the battery cells 12 is relatively constant.

[0045] By selectively omitting turbulator material upstream of the turbulators 53, 54, and 55, the coolant flow is controlled and influenced, thereby improving the temperature gradient across the length and width of the cooling plate 14. Overall, the temperature gradient facing the surface above the cooling surfaces 15 and 16 is reduced to provide a more uniform temperature transfer away from the battery cells 23. When omitting turbulator material from the upstream channel sections 32, 33, 34, and 35 supplied by the inlet port 21, these channel sections 32, 33, 34, and 35 are preferably made narrower to prevent the channel sections 32, 33, 34, and 35 from expanding under pressure. With this configuration, the cooling plate 14 provides improved performance—a more uniform temperature gradient across the cooling surfaces 15 and 16. In addition, the construction avoids excessive pressure drop between the inlet port 21 and the outlet port 22.

[0046] As for the configuration of the channel walls 45 , 46 , 47 and 48 , these walls can be formed in the inserts 39A and 39B, wherein the turbulators 53 , 54 and 55 form these channel walls 45 , 46 , 47 and 48 .

[0047] In such as Fig.11In an alternative embodiment as seen in FIG. 1 , the above configuration can be modified to form a second embodiment of a cooling plate 70 that is reconfigured to rearrange the path pattern of the coolant channels 71. Based on the above detailed discussion, the specific features of the cooling plate 70 need not be further discussed. As schematically shown, the cooling plate 70 includes an inlet port 72 and an outlet port 73.

[0048] Here again, a multi-path internal coolant channel 71 is provided that extends between an inlet port 72 and an outlet port 73 to absorb heat from a cooling surface that is formed identically to cooling surfaces 15 and 16. The coolant channel 71 is formed in a multi-path pattern defined by a plurality of channel segments 74 to 79 that flow past one another to form a second variation of a serpentine counterflow pattern through the interior chamber 80 of the cooling plate 70.

[0049] In order to form channel sections 74 to 79 and generate turbulence within portions of coolant channel 71, interior chamber 80 is subdivided by channel walls 81 to 84 to define channel sections 74 to 79. First channel wall 81 extends centrally to divide channel sections 74 and 75, which are fed by coolant received from inlet port 72 and supplies the coolant to first channel section 74, which in turn feeds the coolant section, which then successively feeds channel sections 77, 78, and 79. Channel section 79 then extends back along channel wall 84 and terminates at outlet 73 so that coolant can be discharged from cooling plate 70 and returned to the cooling system for cooling and recirculation back to inlet port 72.

[0050] The first to fifth channel segments 74 to 79 define another variation of a serpentine counterflow pattern having four paths (i.e., flow paths along channel segments 74, 75, 77, and 79). As the coolant flows along this tortuous path, the coolant receives heat from each or both of the cooling surfaces 15 and 16 to absorb and remove heat from the individual battery cells 23. In this pattern, the coldest channel segment 74 at the inlet port 72 is adjacent to the warmest channel segment 79 at the outlet 73, which provides a more uniform temperature gradient in this area of ​​the cooling plate 70. The heat transfer between the inlet channel segment 74 and the outlet channel segment 79 is very small. However, a more uniform temperature gradient is caused by the placement of the turbulators as described herein.

[0051] The amount of heat transferred from the cooling surfaces 15 and 16 to the coolant is also affected by the flow rate and turbulence throughout the coolant channels 71. In this regard, the three sections 86, 87 and 88 of turbulator material (see Fig.10 ) are arranged in the channel sections 77, 78 and 79. These turbulators are preferably composed of Fig.10The slotted offset fin turbulator pattern is formed.

[0052] To facilitate fluid flow, the second turbulator located in the open end region is cut into a trapezoidal shape so as to have angled end edges 90. In this way, fluid flow in the upstream turbulator 86 in the main flow direction can most easily flow into the angled end edges 90. The trapezoidal turbulator is discharged in a similar manner, wherein the flow in the main flow direction is turned to subsequently flow through the outlet turbulator 88.

[0053] Here again, in order to improve the heat transfer into the coolant, the cooling plate 70 of the present invention also has improved coolant flow, especially the coolant flow starting from the inlet port 72 until entering the first turbulator 86. In this regard, the inlet port 72 leads to the first channel section 74, wherein the first channel section 74 is unrestricted and allows the fluid to flow freely along the channel section 74. The walls of the channel section 74 are relatively smooth to facilitate the flow through it. This allows faster and less turbulent flow, thereby creating a relatively cold inlet area. This is achieved by omitting turbulators or fin materials at the inlet port 72 and preferably along the length of the inlet channel section 74. In addition, turbulators or fin materials can also be omitted from subsequent downstream channel sections 75 and 76 to facilitate fluid flow to the turbulators.

[0054] By selectively omitting turbulator material upstream of the turbulators 86 to 88, heat transfer is reduced and affected, thereby improving the temperature gradient across the length and width of the cooling plate 70. Overall, the temperature gradient facing the surface above the cooling surface is reduced to provide a more uniform temperature transfer away from the battery cells 23. When omitting turbulator material from the upstream channel sections 74 to 75 supplied by the inlet port 72, these channel sections 74 to 75 are preferably made narrower to prevent expansion under pressure, and these turbulators are configured to be wider to accommodate the incoming coolant flow. With this configuration, the cooling plate 70 provides improved performance—a more uniform temperature gradient across the entire cooling surface.

[0055] Next, Fig.12 is a bottom perspective view from the side of a third embodiment of a cooling plate 100 of the present invention, wherein Fig.13 is a bottom cross-sectional view of the cooling plate 100, schematically showing the locations of the inlet and outlet in dashed outline. In light of the above detailed discussion, the specific features of the cooling plate 100 need not be discussed further.

[0056] Generally speaking, the cooling plate 100 includes an inlet 102 and an outlet 103. In this configuration of the cooling plate 100, the cooling plate 100 includes the same arrangement as described above with respect to the cooling plate 14. Here again, a multi-path internal coolant channel 104 is provided, which extends between the inlet 102 and the outlet 103 to absorb heat from the cooling surface, which is formed to be the same as the cooling surfaces 15 and 16. The coolant channel 104 is formed in a multi-path pattern defined by a plurality of channel sections 105 to 111, which flow with each other to form the same serpentine counter-flow pattern present in the cooling plate 14. In this embodiment, the first channel wall 112 begins at a stamped inlet wall section 113 formed by a shell plate similar to the shell plate 29. The inlet wall section 113 forms a short inlet channel 114, which is fed by the coolant received from the inlet 102 and supplies the coolant to the first channel section 105. In this embodiment, the short inlet channel 114 is longer than the short inlet channel described above and curves a greater distance toward the outlet 103. This reduces the size of the reservoir 115 at the outlet compared to the reservoir described above that funnels the coolant flow to the outlet port 22.

[0057] Although certain preferred embodiments of the invention have been disclosed in detail for purposes of illustrative illustration, it will be understood that variations or modifications of the disclosed apparatus, including the rearrangement of parts, are within the scope of the invention.

Claims

1. A battery module, comprising: at least one battery cell; and a cooling plate having a top plate and a bottom plate coupled to each of the battery cells and configured to circulate a coolant through coolant channels thereof, wherein the cooling plate is configured to facilitate transfer of heat from the at least one battery cell to the top plate and the bottom plate of the cooling plate and liquid coolant circulated through the cooling plate; The cooling plate includes an inlet port and an outlet port, the inlet port and the outlet port are in fluid communication with the coolant channel to absorb heat from the top plate and the bottom plate, the coolant channel includes a plurality of channel sections that flow with each other to form a serpentine counter-flow pattern, the channel sections include a first channel section, a second channel section, a third channel section, and a fourth channel section in sequence, wherein the first channel section is in communication with the inlet port, the fourth channel section is in communication with the outlet port, and the first channel section and the fourth channel section are in a parallel adjacent relationship to form a counter-flow arrangement, the coolant channel includes a turbulator downstream of the first channel section, wherein the first channel section is unrestricted and allows free flow of the liquid coolant, and wherein the coolant at the inlet port is cooler than the coolant at the outlet port. 2 . The battery module according to claim 1 , wherein the first channel section has no turbulator in an area close to the inlet port.

3. The battery module according to claim 1, wherein the cooling plate has a plate-like configuration, which is defined by the top plate and the bottom plate and is presented as a surface-enlarging shape on opposite side surfaces of the cooling plate to define a first cooling surface and a second cooling surface, wherein the first cooling surface and the second cooling surface transfer heat from the at least one battery cell to the coolant in the coolant channel. The battery module according to claim 1 , wherein the coolant channel has no turbulator in an upstream region of the turbulator. 5 . The battery module according to claim 3 , wherein the at least one battery cell comprises a plurality of battery cells coupled to at least one of the top plate and the bottom plate. 6 . The battery module according to claim 1 , wherein the first channel section is disposed along a side edge of the cooling plate, and the fourth channel section is disposed inwardly to be adjacent to the cooling plate. 7 . The battery module according to claim 1 , wherein the fourth channel section is disposed along a side edge of the cooling plate, and the first channel section is disposed inwardly to be adjacent to the cooling plate.

8. A cooling plate for a battery module, comprising: a housing defining opposed cooling surfaces disposed on opposite sides of a coolant channel configured to circulate a coolant therethrough and draw heat away from the cooling surfaces and battery cells coupled thereto, wherein the cooling plate is configured to facilitate transfer of heat from the battery cells to liquid coolant circulated through the cooling plate; and The cooling plate includes an inlet port and an outlet port, the inlet port and the outlet port are in fluid communication with the coolant channel to absorb heat from the cooling surface, the coolant channel includes a plurality of channel sections that flow with each other to form a serpentine counter-flow pattern, the coolant channel includes a first channel section, a second channel section, a third channel section, and a fourth channel section in sequence, wherein the first channel section is in communication with the inlet port, the fourth channel section is in communication with the outlet port, and the first channel section and the fourth channel section are in a parallel adjacent relationship to form a counter-flow arrangement, the coolant channel includes a turbulator downstream of the first channel section, wherein the first channel section is unrestricted and allows free flow of the liquid coolant, and wherein the coolant at the inlet port is cooler than the coolant at the outlet port. 9 . The cooling plate of claim 8 , wherein the first channel section has no turbulators in an area close to the inlet.

10. The cooling plate of claim 8, wherein the coolant channels are free of turbulators in an upstream region of the turbulators.

11. The cooling plate of claim 8, wherein the first channel section is disposed along a side edge of the cooling plate, and the fourth channel section is disposed inwardly adjacent to the cooling plate.

12. The cooling plate of claim 8, wherein the fourth channel section is disposed along a side edge of the cooling plate, and the first channel section is disposed inwardly adjacent to the cooling plate.

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