Liquid cooling plate and battery pack

Abstract

The application discloses a liquid cooling plate and a battery pack, and the liquid cooling plate is provided with a cooling flow channel, the cooling flow channel has an inlet port and an outlet port, and the cooling flow channel comprises an inlet flow channel connected to the inlet port, an outlet flow channel connected to the outlet port, and a distribution flow channel connected between the inlet flow channel and the outlet flow channel, wherein the distribution flow channel comprises at least two first distribution sections arranged in parallel, at least one first cross section, and at least two second distribution sections arranged in parallel, the first cross section is connected between the first distribution section and the second distribution section, the number of the first distribution sections and the number of the second distribution sections are both greater than the number of the first cross section, and along the thickness direction of the liquid cooling plate, the projection of the first cross section passes through the projection of the two end plates arranged oppositely on the liquid cooling plate, so that the contact area of the end plate and the liquid cooling plate can be reduced, the invalid heat dissipation of the liquid cooling plate to the end plate can be reduced, and the heat exchange efficiency of the liquid cooling plate can be improved.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a liquid cooling plate and a battery pack. Background Technology

[0002] The battery pack includes multiple liquid cooling plates and multiple cell groups. Each liquid cooling plate has at least two cell groups arranged side by side. The liquid cooling plate has cooling channels inside, and coolant flows in the cooling channels to cool the cell groups. Each cell group consists of multiple individual cells. The two ends of the cell group have end plates for fixing multiple individual cells. The existing cooling channels have a large contact area with the end plates. Since the heat exchange between the cooling channels and the end plates is ineffective, the heat exchange efficiency of the liquid cooling plate is reduced. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention proposes a liquid cooling plate that can improve the heat exchange efficiency of the liquid cooling plate.

[0004] The present invention also proposes a battery pack having the above-mentioned liquid cooling plate.

[0005] According to a first aspect embodiment of the present invention, a liquid cooling plate is provided with cooling channels for cooling at least two battery cell groups arranged side by side along a first direction. Each battery cell group has end plates at both ends. In two adjacent battery cell groups, the end plates of one battery cell group are arranged opposite to the end plates of the other battery cell group. The cooling channels have liquid inlet ports and liquid outlet ports, and the cooling channels include: Liquid inlet channel, connected to the liquid inlet port; A liquid outlet channel, connected to the liquid outlet port; The liquid distribution channel is connected between the inlet channel and the outlet channel. The liquid distribution channel includes at least two first distribution sections arranged in parallel, at least one first crossing section, and at least two second distribution sections arranged in parallel. The first crossing section is connected between the first distribution section and the second distribution section. The number of first distribution sections and the number of second distribution sections are both greater than the number of first crossing sections. Along the thickness direction of the liquid cooling plate, the projection of the first crossing section passes through the projection of the two end plates arranged opposite each other on the liquid cooling plate.

[0006] The liquid-cooled plate according to the first aspect of the present invention has at least the following beneficial effects: When the battery pack is working, the coolant enters the inlet channel through the inlet port. Then, the coolant passes through the first branch section, the first crossover section, and the second branch section in sequence, and finally flows out from the outlet port through the outlet channel. Since the number of the first branch section and the second branch section are both greater than the number of the first crossover section, on the one hand, the contact area between the cell assembly and the liquid cooling plate can be increased, and on the other hand, the contact area between the end plate and the liquid cooling plate can be reduced, so as to reduce the heat exchange between the liquid cooling plate and the end plate, thereby reducing the ineffective heat dissipation of the liquid cooling plate to the end plate and improving the heat exchange efficiency of the liquid cooling plate.

[0007] According to some embodiments of the present invention, the liquid distribution channel further includes a third distribution section and a fourth distribution section, the third distribution section being connected to the liquid inlet channel, and the fourth distribution section being connected between the third distribution section and the first distribution section, wherein the number of fourth distribution sections is greater than the number of third distribution sections and less than the number of first distribution sections.

[0008] According to some embodiments of the present invention, multiple liquid distribution channels are configured, and the multiple liquid distribution channels are arranged side by side at intervals along a second direction. The first direction and the second direction are staggered. The liquid inlet channel includes liquid inlet sections connected in sequence. Each liquid inlet section is connected to the liquid distribution channel. The first liquid inlet section is connected to the liquid inlet port. Along the flow direction of the coolant in the liquid inlet channel, the effective flow area of ​​the multiple liquid inlet sections decreases.

[0009] According to some embodiments of the present invention, the minimum distance between the first branching sections of adjacent liquid distribution channels is D1, the minimum distance between the first crossing sections of adjacent liquid distribution channels is D2, the minimum distance between the third branching sections of adjacent liquid distribution channels is D3, and the minimum distance between the fourth branching sections of adjacent liquid distribution channels is D4, satisfying: D3>D2>D4>D1.

[0010] According to some embodiments of the present invention, the cooling channel further includes an auxiliary channel, at least a portion of which is located between the liquid outlet channel and the liquid distribution channel closest to the liquid outlet port. The auxiliary channel is connected between the liquid inlet channel and the liquid outlet channel, and the auxiliary channel and the liquid outlet channel together cool the same row of individual cells in the cell assembly.

[0011] According to some embodiments of the present invention, the auxiliary flow channel includes a first connecting section, a second connecting section, and a DC section connected in sequence. The first connecting section is connected to the liquid inlet flow channel, and the DC section is connected to the liquid outlet flow channel. The DC section is located between the liquid outlet flow channel and the liquid distribution flow channel closest to the liquid outlet port. Along the thickness direction of the liquid cooling plate, the projection of the end plate does not coincide with the projection of the second connecting section.

[0012] According to some embodiments of the present invention, the liquid distribution channel further includes a fifth distribution section, and a bend section is provided between the fifth distribution section and the second distribution section. The fifth distribution section and the second distribution section both extend along the first direction, and a portion of the bend section extends along the first direction.

[0013] According to some embodiments of the present invention, the liquid outlet channel includes at least two first liquid outlet sections arranged in parallel, at least one second cross section, and at least two second liquid outlet sections arranged in parallel. The first liquid outlet sections are connected to the liquid distribution channel, and the second cross section is connected between the first liquid outlet sections and the second liquid outlet sections. The number of the first liquid outlet sections and the number of the second liquid outlet sections are both greater than the number of the second cross section. Along the thickness direction of the liquid cooling plate, the projections of the two end plates arranged opposite to each other on the liquid cooling plate coincide with the second cross section.

[0014] According to some embodiments of the present invention, the liquid outlet channel includes N parallel liquid outlet sections and N-1 confluence sections, where N≥3 and N is a positive integer. The liquid outlet sections are connected to the liquid distribution channel. Among three adjacent liquid outlet sections, the first liquid outlet section and the second liquid outlet section are connected through a first confluence section, and the third liquid outlet section is connected to the first confluence section through a second confluence section. The second confluence section is connected to the liquid outlet port. The effective flow area of ​​the second confluence section is greater than the effective flow area of ​​the first confluence section, and the effective flow area of ​​the first confluence section is greater than the effective flow area of ​​the liquid outlet section.

[0015] According to some embodiments of the present invention, a plurality of liquid distribution channels are configured, and the plurality of liquid distribution channels are arranged side by side at intervals along a second direction. The first direction and the second direction are staggered. A merging channel is provided between the liquid distribution channels and the liquid outlet channels. The merging channel includes at least two first channels arranged in parallel, and adjacent first channels are connected through second channels.

[0016] The battery pack according to a second aspect of the present invention includes the liquid cooling plate described in the above embodiments.

[0017] The battery pack according to the second aspect of the present invention has at least the following beneficial effects: When the battery pack is in operation, the coolant enters the inlet channel through the inlet port using the liquid cooling plate of the first aspect embodiment of the present invention. Then, the coolant passes through the first branch section, the first cross section and the second branch section in sequence, and finally flows out from the outlet port through the outlet channel. Since the number of the first branch section and the number of the second branch section are both greater than the number of the first cross section, on the one hand, the contact area between the cell assembly and the liquid cooling plate can be increased, and on the other hand, the contact area between the end plate and the liquid cooling plate can be reduced, so as to reduce the heat exchange between the liquid cooling plate and the end plate, thereby reducing the ineffective heat dissipation of the liquid cooling plate to the end plate and improving the heat exchange efficiency of the liquid cooling plate.

[0018] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein: Figure 1 This is a schematic diagram of the structure of the liquid cooling plate according to an embodiment of the present invention; Figure 2 This is an exploded view of the liquid cooling plate according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the cooling flow channel of the liquid cooling plate according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the assembly of the cooling channel and the battery cell assembly according to an embodiment of the present invention; Figure 5 for Figure 4 Top view.

[0020] Icon labels: Flow channel plate 101, cover plate 102, liquid inlet port 110, liquid outlet port 120; Liquid inlet channel 200, first liquid inlet section 210, second liquid inlet section 220, third liquid inlet section 230, bifurcation section 240; Liquid outlet channel 300, first liquid outlet section 310, second cross section 320, second liquid outlet section 330, first confluence section 340, second confluence section 350; First diversion section 410, first crossing section 420, second diversion section 430, third diversion section 440, fourth diversion section 450, fifth diversion section 460, bend section 470, first straight section 471, second straight section 472, third straight section 473; First flow channel 510, second flow channel 520; Auxiliary flow channel 600, first connecting section 610, second connecting section 620, DC section 630. Detailed Implementation

[0021] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0022] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, etc., are based on the orientation or positional relationship shown in the drawings and are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0023] In the description of this invention, "multiple" refers to two or more. The use of "first" and "second" is for distinguishing technical features only and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features or their sequential relationship.

[0024] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0025] In related technologies, a battery pack includes multiple liquid cooling plates and multiple cell groups. Each liquid cooling plate has at least two cell groups arranged side by side. The liquid cooling plate has cooling channels inside, and coolant flows in the cooling channels to cool the cell groups. Each cell group consists of multiple individual cells. The two ends of the cell group have end plates for fixing multiple individual cells. The existing cooling channels have a large contact area with the end plates. Since the heat exchange between the cooling channels and the end plates is ineffective, the heat exchange efficiency of the liquid cooling plate is reduced.

[0026] Based on this, refer to Figures 1 to 3 , Figure 1 This is a schematic diagram of the structure of the liquid cooling plate according to an embodiment of the present invention. Figure 2 This is an exploded view of the liquid cooling plate according to an embodiment of the present invention. Figure 3 This is a schematic diagram of the cooling flow channel of the liquid cooling plate according to an embodiment of the present invention. Figure 3 The arrows inside the cooling channels indicate the direction of coolant flow. For example... Figures 1 to 3As shown, a first aspect embodiment of the present invention provides a liquid cooling plate, which is provided with cooling channels for cooling two battery cell groups 700 arranged side by side along a first direction. Each battery cell group 700 has end plates 720 at both ends. The cooling channels have an inlet port 110 and an outlet port 120. In two adjacent battery cell groups 700, the end plates 720 of one battery cell group 700 are arranged opposite to the end plates 720 of the other battery cell group 700. The cooling channels include an inlet channel 200 connected to the inlet port 110, an outlet channel 300 connected to the outlet port 120, and a distribution channel, which connects the inlet channel 200 and the outlet channel. Between 300, the liquid distribution channel includes three parallel first distribution sections 410, two first crossing sections 420, and four parallel second distribution sections 430. One end of the first crossing section 420 is connected to the first distribution section 410, and the other end of the first crossing section 420 is connected to the second distribution section 430. Along the thickness direction of the liquid cooling plate, the projection of the first crossing section 420 passes through the projection of the two oppositely arranged end plates 720 on the liquid cooling plate. In this way, the contact area between the end plates 720 and the liquid cooling plate can be reduced, thereby reducing the heat exchange between the liquid cooling plate and the end plates 720, thus reducing the ineffective heat dissipation of the liquid cooling plate to the end plates 720, and improving the heat exchange efficiency of the liquid cooling plate.

[0027] For example, when the battery pack is working, the coolant enters the inlet channel 200 through the inlet port 110. Then, the coolant passes through the first branch section 410, the first crossover section 420, and the second branch section 430 in sequence, and finally flows out from the outlet port 120 through the outlet channel 300. Since the number of the first branch sections 410 and the second branch sections 430 is greater than the number of the first crossover sections 420, on the one hand, the contact area between the cell assembly 700 and the liquid cooling plate can be increased, and on the other hand, the contact area between the end plate 720 and the liquid cooling plate can be reduced, so as to reduce the heat exchange between the liquid cooling plate and the end plate 720, thereby reducing the ineffective heat dissipation of the end plate 720 by the liquid cooling plate and improving the heat exchange efficiency of the liquid cooling plate.

[0028] It should be noted that the first diversion section 410 can be configured with two, four, or five, the first bypass section 420 can be configured with one, three, or four, and the second diversion section 430 can be configured with two, three, or five, as long as the number of the first diversion section 410 and the number of the second diversion section 430 are both greater than the number of the first bypass section 420. For example, the first diversion section 410 and the second diversion section 430 can both be configured with two, and the first bypass section 420 can be configured with one. This will not be elaborated further here.

[0029] It should be noted that each liquid cooling plate can cool two, three or four battery cell groups 700. Taking the liquid cooling plate cooling three battery cell groups 700 arranged side by side along the first channel as an example, each liquid distribution channel has two first crossing sections 420, and two corresponding first diversion sections 410 and second diversion sections 430. The number of first crossing sections 420 is one less than the number of battery cell groups 700, which will not be elaborated here.

[0030] It should be noted that, for example, Figure 1 , Figure 2 As shown, the liquid cooling plate includes a flow channel plate 101 and a cover plate 102. The flow channel plate 101 has a cooling flow channel formed by a recessed structure. The cover plate 102 covers the flow channel plate 101 to seal the cooling flow channel. The liquid inlet port 110 and the liquid outlet port 120 are provided on the flow channel plate 101 or the cover plate 102. The recessed structure on the flow channel plate 101 can be formed by stamping, which facilitates the production and manufacturing of the liquid cooling plate. Further details will not be provided here.

[0031] In this embodiment, the liquid distribution channel further includes a third distribution section 440 and a fourth distribution section 450. One end of the third distribution section 440 is connected to the liquid inlet channel 200, and the other end of the third distribution section 440 is connected to the fourth distribution section 450. The end of the fourth distribution section 450 away from the third distribution section 440 is connected to the first distribution section 410. That is, the third distribution section 440, the fourth distribution section 450, and the first distribution section 410 are connected in sequence. There is one third distribution section 440, two fourth distribution sections 450, and three first distribution sections 410. The number of third distribution sections 440, the number of fourth distribution sections 450, and the number of first distribution sections 410 gradually increases. The coolant passes through the third distribution section 440, the fourth distribution section 450, and the first distribution section 410 in sequence, so that the coolant is evenly distributed on the cell assembly 700 to prevent local overheating of the cell assembly 700.

[0032] For example, in the battery pack, each liquid cooling plate is provided with two sets of cell groups 700. The two sets of cell groups 700 are arranged at intervals along the first direction. One of the two sets of cell groups 700 contacts the third branch section 440, the fourth branch section 450 and the first branch section 410, and the other set contacts the second branch section 430. During the actual operation of the battery pack, the temperature of the coolant in the liquid inlet channel 200 is relatively low. As the flow path of the coolant increases, the coolant gradually absorbs the heat dissipated by the cell group 700, and the temperature of the coolant gradually increases. This can gradually increase the contact area between the liquid cooling plate and the cell group 700, so as to gradually improve the heat exchange efficiency of the coolant. This makes the cooling effect of the coolant in the first branch section 410, the second branch section 430, the third branch section 440 and the fourth branch section 450 similar, which can prevent the cell group 700 from overheating. This will not be described in detail here.

[0033] As another implementation, the number of third branch sections 440, fourth branch sections 450, and first branch sections 410 can be increased sequentially. For example, there can be two third branch sections 440, four fourth branch sections 450, and six first branch sections 410. As long as the number of fourth branch sections 450 is greater than the number of third branch sections 440 and the number of fourth branch sections 450 is less than the number of first branch sections 410, there is no limitation here.

[0034] It is understood that the battery cell assembly 700 includes multiple individual battery cells 710, which are arranged in a rectangular array with intervals. In order to meet the heat dissipation requirements of individual battery cells 710 in different columns, in this embodiment, multiple liquid distribution channels are configured. The multiple liquid distribution channels are arranged side by side with intervals along the second direction, and the first direction is perpendicular to the second direction. Each liquid distribution channel corresponds to the same column of individual battery cells 710 in the battery cell assembly 700, and the liquid outlet channel 300 corresponds to a single column of individual battery cells 710, which can prevent the battery cell assembly 700 from generating local overheating.

[0035] It should be noted that the first direction is the length direction of the liquid cooling plate, and the second direction is the width direction of the liquid cooling plate, which will not be elaborated here.

[0036] It is understandable that the angle between the first direction and the second direction can also be an acute angle or an obtuse angle, and there are no restrictions here.

[0037] For example Figure 3 As shown, in this embodiment, the liquid inlet channel 200 includes a first liquid inlet section 210, a second liquid inlet section 220, and a third liquid inlet section 230 arranged in a stepped manner. One end of the second liquid inlet section 220 is connected to the first liquid inlet section 210, and the other end of the second liquid inlet section 220 is connected to the third liquid inlet section 230. The end of the first liquid inlet section 210 away from the second connecting section 620 is connected to the liquid inlet port 110. The first liquid inlet section 210, the second liquid inlet section 220, and the third liquid inlet section 230 are respectively connected to a third diversion section 440. The effective flow area of ​​the first inlet section 210 is smaller than that of the second inlet section 220, and the effective flow area of ​​the third inlet section 230 is larger than that of the third inlet section 230. This can effectively reduce the pressure difference between the first inlet section 210, the second inlet section 220, and the third inlet section 230, prevent turbulence and eddies in the coolant at the inlet end of the first flow channel 510, make the coolant distribution process smoother, and ensure that the inlet flow rate of the coolant entering each first flow channel 510 is similar, so as to prevent local overheating of the cell assembly 700.

[0038] For example, let's consider the third branch section 440 connected to the first inlet section 210 as the first third branch section 440, the third branch section 440 connected to the second inlet section 220 as the second third branch section 440, and the third branch section 440 connected to the third inlet section 230 as the third third branch section 440. When the liquid cooling plate is working, some of the coolant in the first inlet section 210 flows into the first third branch section 440, another portion of the coolant in the first inlet section 210 flows into the second inlet section 220, some of the coolant in the second inlet section 220 flows into the second third branch section 440, and another portion of the coolant in the second inlet section 220 flows into the third inlet section 230. That is, the flow rate of the coolant in the first inlet section 210 is greater than the flow rate of the coolant in the second inlet section 220. The flow rate of the coolant in the third inlet section 230 is greater than that in the second inlet section 220. Since the effective flow area of ​​the second inlet section 220 is smaller than that of the first inlet section 210, and the effective flow area of ​​the second inlet section 220 is larger than that of the third inlet section 230, the flow velocity of the coolant in the third inlet section 230 is greater than that in the second inlet section 220, and the flow velocity of the coolant in the second inlet section 220 is greater than that in the first inlet section 210. This can effectively reduce the pressure difference between the first inlet section 210, the second inlet section 220, and the third inlet section 230, prevent turbulence and eddies in the coolant at the inlet end of the first flow channel 510, make the coolant distribution process smoother, and ensure that the inlet flow rate of the coolant entering each first flow channel 510 is similar, so as to prevent local overheating of the cell assembly 700.

[0039] It should be noted that, along the flow direction of the coolant in the inlet channel 200, the effective flow area of ​​the first inlet section 210, the second inlet section 220, and the third inlet section 230 gradually decrease, which can also reduce the pressure difference between the first inlet section 210, the second inlet section 220, and the third inlet section 230. This is not a limitation.

[0040] In this embodiment, the minimum distance between the first branch sections 410 of adjacent liquid distribution channels is D1, the minimum distance between the first cross sections 420 of adjacent liquid distribution channels is D2, the minimum distance between the third branch sections 440 of adjacent liquid distribution channels is D3, and the minimum distance between the fourth branch sections 450 of adjacent liquid distribution channels is D4, satisfying: D3 > D2 > D4 > D1. The second branch section 430 and the first branch section 410 of each liquid distribution channel are suitable for the high heat load area of ​​the cell assembly 700. The third branch section 440 of each first channel 510... Sections 0 and 450 are suitable for the low heat load area of ​​the cell assembly 700. By rationally designing the relationship between the minimum distance D1 between the first branch section 410 of the adjacent liquid distribution channel, the minimum distance D2 between the first cross section 420 of the adjacent liquid distribution channel, the minimum distance D3 between the third branch section 440 of the adjacent liquid distribution channel, and the minimum distance D4 between the fourth branch section 450 of the adjacent liquid distribution channel, the heat dissipation requirements of the cell assembly 700 can be met and the efficient flow of coolant can be promoted, ensuring that the coolant flow rate of each liquid distribution channel is uniform.

[0041] In this example, the effective flow area of ​​the first liquid inlet section 210 is S1, the effective flow area of ​​the second liquid inlet section 220 is S2, and the effective flow area of ​​the third liquid inlet section 230 is S3, satisfying the condition that S1 > S2 > S3. This can prevent turbulence and eddies from occurring at the inlet end of the first flow channel 510, making the coolant distribution process smoother and ensuring that the inlet flow rate of coolant entering each first flow channel 510 is similar, thereby preventing local overheating of the cell assembly 700.

[0042] It is understandable that during fluid flow, the fluid preferentially chooses to enter the flow channel with lower flow resistance, resulting in uneven fluid flow distribution.

[0043] In this embodiment, the liquid distribution channel further includes a fifth distribution section 460. A bend section 470 is provided between the fifth distribution section 460 and the second distribution section 430. The coolant passes through the second distribution section 430, the bend section 470, and the fifth distribution section 460 in sequence. The bend section 470 includes a first straight section 471, a second straight section 472, and a third straight section 473 connected in sequence. The first straight section 471, the second straight section 472, and the third straight section 473 are generally U-shaped. The first straight section 471 and the third straight section 473 extend along a first direction. The second straight segment 472 extends along the second direction, and the second diversion segment 430 and the fifth diversion segment 460 both extend along the first direction. The flow direction of the coolant in the first straight segment 471 is opposite to the flow direction of the coolant in the third straight segment 473. On the one hand, this makes the layout of the liquid distribution channel compact, so as to reduce the overall space occupied by the liquid cooling plate. On the other hand, it can increase the flow path of the coolant in the high-temperature area in the middle of the liquid cooling plate, so that the temperature distribution in the high-temperature area in the middle of the liquid cooling plate is more uniform, and the possibility of local overheating of the cell assembly 700 is reduced.

[0044] It should be noted that when the coolant flows in the bend section 470, as the flow path of the coolant increases, the coolant gradually absorbs the heat dissipated by the battery cell assembly 700, and the temperature of the coolant gradually increases. That is, the temperature of the coolant in the third straight section 473 is greater than the temperature of the coolant in the second straight section 472, and the temperature of the coolant in the second straight section 472 is greater than the temperature of the coolant in the first straight section 471. Since the first straight section 471, the second straight section 472, and the third straight section 473 are U-shaped, under the action of thermal radiation, the coolant in the first straight section 471 can exchange heat with the coolant in the second straight section 472, and the coolant in the second straight section 472 can exchange heat with the coolant in the third straight section 473. This reduces the temperature difference of the coolant at different positions in the bend section 470, making the temperature distribution in the high-temperature area in the middle of the liquid cooling plate more uniform and reducing the possibility of local overheating of the battery cell assembly 700.

[0045] As another implementation, the first straight segment 471, the second straight segment 472, and the third straight segment 473 can also be in a Z-shaped structure, which is not limited here.

[0046] It should be noted that multiple bends 470 may also include a fourth or fifth straight segment, which is not limited here.

[0047] For example Figure 3As shown, in this embodiment, the cooling channel also includes an auxiliary channel 600. Part of the auxiliary channel 600 is located between the liquid outlet channel 300 and the liquid distribution channel closest to the liquid outlet port 120. One end of the auxiliary channel 600 is connected to the third liquid inlet section 230, and the other end of the auxiliary channel 600 is connected to the liquid outlet channel 300. The auxiliary channel 600 and the liquid outlet channel 300 jointly cool the same row of individual cells 710 in the cell assembly 700. The cooling energy of the coolant in the auxiliary channel 600 is greater than that of the coolant in the liquid outlet channel 300, so that the coolant in the auxiliary channel 600 can assist the coolant in the liquid outlet channel 300 in dissipating heat from the cell assembly 700, thereby reducing the temperature difference between different individual cells 710 and preventing local overheating of the cell assembly 700.

[0048] It should be noted that as the flow path of the coolant increases, the temperature of the coolant in the outlet channel 300 is higher than that in the distribution channel, resulting in a weaker cooling effect of the coolant in the outlet channel 300 compared to that in the distribution channel. By setting up an auxiliary channel 600, which directly cools the individual cells 710 in the same row that are in contact with the outlet channel 300, the coolant in the auxiliary channel 600 can assist the coolant in the outlet channel 300 in dissipating heat from the cell assembly 700, thereby reducing the temperature difference between different individual cells 710 and preventing localized overheating of the cell assembly 700.

[0049] In another implementation, the auxiliary flow channel 600 may also be connected to the first liquid inlet section 210 or the second liquid inlet section 220, without limitation.

[0050] For example Figure 3 As shown, in this embodiment, the auxiliary flow channel 600 includes a first connecting section 610, a second connecting section 620, and a direct flow section 630 connected in sequence. The first connecting section 610, the second connecting section 620, and the direct flow section 630 are generally U-shaped. The direct flow section 630 is located between the liquid outlet flow channel 300 and the liquid distribution flow channel closest to the liquid outlet port 120. The end of the direct flow section 630 away from the second connecting section 620 is connected to the second flow channel 520. The first connecting section 610 is connected to the third liquid inlet section 230. The direct flow section 630 extends along a first direction, and the first connecting section 610 extends along the first direction. The second connecting segment 620 extends along the second direction, along the thickness direction of the liquid cooling plate. The projection of the second connecting segment 620 does not coincide with the projection of the end plate 720, so that the first connecting segment 610 and the second connecting segment 620 can avoid the end plate 720 of the cell assembly 700 near the liquid inlet port 101. This reduces the contact area between the liquid cooling plate and the end plate 720 of the cell assembly 700 near the liquid inlet port 101, thereby reducing the ineffective heat dissipation of the auxiliary flow channel 600 on the end plate 720 of the cell assembly 700 near the liquid inlet port 101, and thus improving the cooling effect of the liquid cooling plate.

[0051] In another implementation, the auxiliary flow channel 600 may also include only a DC section 630. The DC section 630 is connected between the end of the third liquid inlet section 230 and the second flow channel 520. The DC section 630 is located between the liquid outlet flow channel 300 and the liquid distribution flow channel closest to the liquid outlet port 120. That is, the auxiliary flow channel 600 is completely located between the liquid outlet flow channel 300 and the liquid distribution flow channel closest to the liquid outlet port 120. It can also assist the coolant in the liquid outlet flow channel 300 in dissipating heat from the battery cell assembly 700. This will not be described in detail here.

[0052] In this example, the effective flow area of ​​the first liquid inlet section 210 is S1, the effective flow area of ​​the second liquid inlet section 220 is S2, the effective flow area of ​​the third liquid inlet section 230 is S3, and the effective flow area of ​​the second connecting section 620 is S4, satisfying the condition: S1 > S2 > S3 > S4. This can prevent turbulence and eddies from occurring at the inlet end of the first flow channel 510, making the coolant distribution process smoother and ensuring that the inlet flow rate of coolant entering each first flow channel 510 is similar, thereby preventing local overheating of the cell assembly 700.

[0053] It should be noted that, for example, Figure 3 As shown, the width of the first liquid inlet section 210 is L1, the width of the second liquid inlet section 220 is L2, the width of the third liquid inlet section 230 is L3, the width of the second connecting end section is L4, and the depth of the recessed structure at each position on the flow channel plate 101 is equal, such that S1>S2>S3>S4=L1>L2>L3>L4, which will not be elaborated further here.

[0054] For example Figure 3 As shown, in this embodiment, the liquid outlet channel 300 includes a first liquid outlet section 310, a second crossing section 320, and a second liquid outlet section 330. One end of the second crossing section 320 is connected to the first liquid outlet section 310, and the other end of the second crossing section 320 is connected to the second liquid outlet section 330. The coolant in the liquid outlet channel passes sequentially through the first liquid outlet section 310, the second crossing section 320, and the second liquid outlet section 330, and finally flows out from the liquid outlet port 120. Three of each of the first and second liquid outlet sections 310 and 330 are provided, and two of the second crossing sections 320 are provided. Along the thickness direction of the liquid cooling plate, the projection of the second crossing section 320 passes through the projections of the two oppositely arranged end plates 720, which reduces the contact area between the liquid outlet channel 300 and the first and second end plates 720, thereby reducing ineffective heat dissipation from the liquid outlet channel 300 to the first and second end plates 720, and thus improving the cooling effect of the liquid cooling plate. It should be noted that the number of the first liquid outlet section 310 can also be configured to be five, the number of the second liquid outlet section 330 to be four, and the number of the second cross section 320 to be one, as long as the number of the first liquid outlet section 310 and the number of the second liquid outlet section 330 are both greater than the number of the second cross section 320, which will not be elaborated here.

[0055] In this embodiment, the multiple second liquid outlet sections 330 include a first section, a second section, and a third section arranged in parallel. The confluence section includes a first sub-confluence section and a second sub-confluence section. The first section and the second section are both connected to the first sub-confluence section. The third section and the first sub-confluence section are both connected to the second sub-confluence section. The second sub-confluence section is connected to the liquid outlet port 120. The effective flow area of ​​the second sub-confluence section is greater than the effective flow area of ​​the first sub-confluence section.

[0056] In this embodiment, the coolant outlet channel 300 includes N parallel outlet sections and N-1 confluence sections, where N ≥ 3 and N is a positive integer. In three adjacent outlet sections, the first and second outlet sections are connected by a first confluence section 340, and the third outlet section is connected to the first confluence section 340 by a second confluence section 350. The second confluence section 350 connects to the outlet port 120. The effective flow area of ​​the second confluence section 350 is greater than that of the first confluence section 340, and the effective flow area of ​​the first confluence section 340 is greater than that of the outlet section. By setting the first confluence section 340 and the second confluence section 350, the coolant can be gradually buffered, effectively preventing pressure fluctuations during the confluence process at the outlet port 120, thus ensuring that the coolant leaves the cooling channel smoothly. N can be 3, 4, 5, 6, 7, etc., and is not limited here.

[0057] It should be noted that the above-mentioned outlet section is the second outlet section 330. At this time, the coolant in the second cross section 320 is divided into three second outlet sections 330. Among the three second outlet sections 330, the coolant in two of the second outlet sections 330 first merges in the first confluence section 340. Then, the coolant in the third second outlet section 330 and the coolant in the first confluence section 340 merge in the second confluence section 350. This can effectively avoid pressure fluctuations during the merging process at the outlet port 120, ensuring that the coolant leaves the cooling channel smoothly. Alternatively, the above-mentioned outlet section can be directly connected to the distribution channel, which is not restricted here.

[0058] In this embodiment, a converging channel is provided between the liquid distribution channel and the liquid outlet channel 300. The converging channel includes at least two first channels 510 arranged in parallel. Adjacent first channels 510 are connected through second channels 520. The at least two first channels 510 and at least two second channels 520 are in a grid shape, which can balance the temperature difference at the end of the liquid cooling plate. The first channels 510 and the second channels 520 can buffer the impact force of the coolant from the liquid distribution channel. Under the combined action of the first channels 510, the bend channel and the converging channel, the temperature difference between each cell can be reduced to ensure that the coolant leaves the cooling channel smoothly.

[0059] In this embodiment, the first liquid inlet section 210 is provided with a bifurcation section 240, which connects to the liquid distribution channel closest to the liquid inlet port 110. The angle between the flow direction of the coolant in the first liquid inlet section 210 and the flow direction of the coolant in the bifurcation section 240 is greater than 90°, which can increase the flow resistance of the coolant entering the liquid distribution channel closest to the liquid inlet port 110, so as to avoid too much coolant entering the liquid distribution channel closest to the liquid inlet port 110, thereby ensuring the flow balance of each liquid distribution channel and preventing local overheating of the cell assembly 700.

[0060] For example, the coolant in the first inlet section 210 flows into the distribution channel from the branch section 240 and finally branches into the first channel 510. Since the effective flow area of ​​the first inlet section 210 is greater than that of the second inlet section 220, and the effective flow area of ​​the second inlet section 220 is greater than that of the third inlet section 230, the flow resistance of the coolant in the first inlet section 210 is less than that in the second inlet section 220, and the flow resistance of the coolant in the second inlet section 220 is less than that in the third inlet section 230. By reasonably increasing the flow resistance of the coolant when it enters the branch section 240, too much coolant is prevented from entering the distribution channel closest to the inlet port 110, thereby ensuring the flow balance of each distribution channel and preventing local overheating of the cell assembly 700.

[0061] A second aspect of the present invention provides a battery pack, which includes the liquid cooling plate described in the above embodiment.

[0062] When the battery pack is in operation, the coolant enters the inlet channel 200 through the inlet port 110 using the liquid cooling plate of the first aspect embodiment of the present invention. Then, the coolant passes through the first branch section 410, the first crossover section 420 and the second branch section 430 in sequence, and finally flows out from the outlet port 120 through the outlet channel 300. Since the number of the first branch section 410 and the number of the second branch section 430 are both greater than the number of the first crossover section 420, on the one hand, the contact area between the cell assembly 700 and the liquid cooling plate can be increased, and on the other hand, the contact area between the end plate 720 and the liquid cooling plate can be reduced, so as to reduce the heat exchange between the liquid cooling plate and the end plate 720, thereby reducing the ineffective heat dissipation of the liquid cooling plate to the end plate 720 and improving the heat exchange efficiency of the liquid cooling plate.

[0063] Since the battery pack adopts all the technical solutions of the liquid cooling plate in the above embodiments, it has at least all the beneficial effects brought about by the technical solutions in the above embodiments, which will not be repeated here.

[0064] The present invention has been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiment. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A liquid-cooled plate, wherein the liquid-cooled plate is provided with cooling channels for cooling at least two battery cell groups arranged side by side along a first direction, each battery cell group having end plates at both ends, and in two adjacent battery cell groups, the end plates of one battery cell group are arranged opposite to the end plates of the other battery cell group, the cooling channels having liquid inlet ports and liquid outlet ports, characterized in that, The cooling channel includes: Liquid inlet channel, connected to the liquid inlet port; A liquid outlet channel, connected to the liquid outlet port; The liquid distribution channel is connected between the inlet channel and the outlet channel. The liquid distribution channel includes at least two first distribution sections arranged in parallel, at least one first crossing section, and at least two second distribution sections arranged in parallel. The first crossing section is connected between the first distribution section and the second distribution section. The number of first distribution sections and the number of second distribution sections are both greater than the number of first crossing sections. Along the thickness direction of the liquid cooling plate, the projection of the first crossing section passes through the projection of the two end plates arranged opposite each other on the liquid cooling plate.

2. The liquid cooling plate according to claim 1, characterized in that: The liquid distribution channel further includes a third distribution section and a fourth distribution section. The third distribution section is connected to the liquid inlet channel, and the fourth distribution section is connected between the third distribution section and the first distribution section. The number of fourth distribution sections is greater than the number of third distribution sections and less than the number of first distribution sections.

3. The liquid cooling plate according to claim 1, characterized in that: The liquid distribution channel is configured with multiple channels, which are arranged side by side at intervals along the second direction. The first direction and the second direction are staggered. The liquid inlet channel includes inlet sections connected in sequence. Each inlet section is connected to the liquid distribution channel. The first inlet section is connected to the inlet port. Along the flow direction of the coolant in the liquid inlet channel, the effective flow area of ​​the multiple inlet sections decreases.

4. The liquid cooling plate according to claim 3, characterized in that: The minimum distance between the first branching sections of adjacent liquid distribution channels is D1, the minimum distance between the first crossing sections of adjacent liquid distribution channels is D2, the minimum distance between the third branching sections of adjacent liquid distribution channels is D3, and the minimum distance between the fourth branching sections of adjacent liquid distribution channels is D4, satisfying the following condition: D3 > D2 > D4 > D1.

5. The liquid cooling plate according to claim 1, characterized in that: The cooling channel further includes an auxiliary channel, at least a portion of which is located between the liquid outlet channel and the liquid distribution channel closest to the liquid outlet port. The auxiliary channel is connected between the liquid inlet channel and the liquid outlet channel, and the auxiliary channel and the liquid outlet channel together cool the same row of individual cells in the cell assembly.

6. The liquid cooling plate according to claim 5, characterized in that: The auxiliary flow channel includes a first connecting section, a second connecting section, and a DC section connected in sequence. The first connecting section is connected to the liquid inlet flow channel, and the DC section is connected to the liquid outlet flow channel. The DC section is located between the liquid outlet flow channel and the liquid distribution flow channel closest to the liquid outlet port. Along the thickness direction of the liquid cooling plate, the projection of the end plate does not coincide with the projection of the second connecting section.

7. The liquid cooling plate according to claim 1, characterized in that: The liquid distribution channel further includes a fifth distribution section, and a bend section is provided between the fifth distribution section and the second distribution section. Both the fifth distribution section and the second distribution section extend along the first direction, and a portion of the bend section extends along the first direction.

8. The liquid cooling plate according to claim 1, characterized in that: The liquid outlet channel includes at least two first liquid outlet sections arranged in parallel, at least one second cross section, and at least two second liquid outlet sections arranged in parallel. The first liquid outlet sections are connected to the liquid distribution channel, and the second cross section is connected between the first liquid outlet sections and the second liquid outlet sections. The number of the first liquid outlet sections and the number of the second liquid outlet sections are both greater than the number of the second cross section. Along the thickness direction of the liquid cooling plate, the projections of the two end plates arranged opposite each other on the liquid cooling plate coincide with the second cross section.

9. The liquid cooling plate according to claim 1, characterized in that: The liquid outlet channel includes N parallel liquid outlet sections and N-1 confluence sections, where N ≥ 3 and N is a positive integer. The liquid outlet sections are connected to the liquid distribution channel. Among three adjacent liquid outlet sections, the first liquid outlet section and the second liquid outlet section are connected through a first confluence section, and the third liquid outlet section is connected to the first confluence section through a second confluence section. The second confluence section is connected to the liquid outlet port. The effective flow area of ​​the second confluence section is greater than the effective flow area of ​​the first confluence section, and the effective flow area of ​​the first confluence section is greater than the effective flow area of ​​the liquid outlet section.

10. The liquid cooling plate according to claim 1, characterized in that: The liquid distribution channel is configured with multiple channels, which are arranged side by side at intervals along the second direction. The first direction and the second direction are staggered. A merging channel is provided between the liquid distribution channel and the liquid outlet channel. The merging channel includes at least two first channels arranged in parallel, and adjacent first channels are connected through second channels.

11. A battery pack, characterized in that: Includes the liquid cooling plate according to any one of claims 1-10.

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