Multi-protection liquid cooling battery pack structure and system

Abstract

The invention belongs to the technical field of batteries, and particularly relates to a multi-protection liquid-cooled battery pack structure and system.The multi-protection liquid-cooled battery pack structure comprises a battery shell, and the battery shell is used for sealing and containing an internal space of a plurality of battery units; the heat transfer device is provided with an inlet, an outlet and at least one fluid channel arranged between the inlet and the outlet, and fluid can flow from the inlet to the outlet through the heat transfer device through the at least one fluid channel; wherein at least one fluid channel is arranged in the interior and the contact side of the channel can be pressed against at least one contact element for heat transfer, the advantage of the invention is that surface-to-surface heat transfer is ensured, the use of mechanical spring elements for generating contact pressure is not required, and the contact side can be pressed against at least one contact element for heat transfer. Because the at least one fluid channel is pressed against the contact element only during use, the mechanical load is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and in particular relates to a multi-protection liquid-cooled battery pack structure and system. Background Art

[0002] With the widespread application of high-energy-density batteries in electric vehicles, energy storage systems and other fields, battery thermal management technology has become the key to ensuring their safety and performance. Traditional liquid-cooled battery packs usually use metal shells to encapsulate battery cells and achieve heat exchange through built-in cooling channels. However, the existing technology has the following defects. The cooling channels of conventional liquid cooling systems are usually in contact with battery cells through rigid heat conducting plates. During long-term charge and discharge cycles, the contact pressure is easily reduced due to material deformation or vibration, forming a thermal resistance layer, which seriously affects the heat dissipation efficiency. Existing cooling channels mostly use flexible pipes or thin-walled metal pipes, which are prone to deformation when the coolant pressure fluctuates or the temperature changes, resulting in changes in the cross-sectional area of the channel, and even causing the channel to collapse, hindering the circulation of the cooling medium. Summary of the Invention

[0003] In view of the above-mentioned deficiencies in the prior art, the present invention provides a multi-protection liquid-cooled battery pack structure and system to solve the problems of insufficient thermal contact efficiency in the prior art.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0005] The invention comprises a battery housing for enclosing an interior space for accommodating a plurality of battery cells, and a heat transfer device having an inlet and an outlet and at least one fluid channel arranged between the inlet and the outlet, wherein a fluid can flow from the inlet through the heat transfer device to the outlet via the at least one fluid channel, wherein the at least one fluid channel is arranged inside, and a contact side of the channel can be pressed against at least one contact element to transfer heat.

[0006] Furthermore, at least one expansion element is provided, which expands due to the pressurization of the fluid in the heat transfer device, thereby pressing the at least one fluid channel against the at least one contact element via the support surface.

[0007] Another advantage of the battery housing assembly is its ability to compensate for component tolerances and deformations during operation, which occur automatically under load (i.e., during fluid supply). This allows for reliable charging and discharging of liquid-cooled batteries. Furthermore, since compression adjustments to at least one fluid channel are generally unnecessary, the heat transfer device is highly reusable.

[0008] Furthermore, pressing the at least one fluid channel against the at least one contact element allows for force transmission, thereby ensuring that the battery cell is also in thermal contact with the contact element. The battery cell is typically in thermal contact with the contact element from the side opposite the at least one fluid channel.

[0009] The vehicle can be any electrically driven vehicle, such as a pure electric vehicle, or a so-called hybrid vehicle consisting of an electric drive and an additional drive device (such as an internal combustion engine). The number and arrangement of the electric drive motors in the vehicle are irrelevant to the present invention.

[0010] Furthermore, the battery housing can be designed in two parts, for example, consisting of a bottom and a lid, so that the battery housing can be closed after the battery cells are inserted. The battery housing can also be opened to provide access to the battery cells. The battery housing can be made of metal, for example. However, the battery housing is preferably made of plastic or a composite material to reduce weight. Since the mechanical load caused by the squeezing of at least one fluid channel is only temporary, the tolerance requirements on the battery housing can be relaxed. In addition, the rigidity requirements on the battery housing can be reduced, thereby reducing weight. This can also reduce the risk of sagging.

[0011] Furthermore, the heat transfer device includes an inlet and an outlet through which a fluid circulates. The inlet and outlet can lead to the exterior of the battery housing or can be located within the battery housing, for example, to distribute the fluid within the battery housing, particularly in the case of a multi-layer arrangement of battery cells. At least one fluid channel acts as a heat exchanger, absorbing heat from or releasing heat to the contact elements, depending on the operation of the heat transfer device. This allows the temperature of the battery cells to be controlled for optimal operation and maximum energy storage capacity.

[0012] Furthermore, the fluid can be a gas or a liquid. Heat can be transferred from the fluid to the battery cell, and vice versa, via at least one fluid channel and at least one contact element. A cooling circuit can be provided in which the fluid changes its material state, thereby absorbing heat through evaporation or releasing heat through condensation. This allows for particularly efficient temperature control of the battery cell.

[0013] Furthermore, at least one fluid channel is arranged inside for transferring heat to at least one contact element or absorbing heat from at least one contact element. At least one contact element is in thermal contact with the battery cell to further transfer heat. At least one contact element is usually made of a metal with high thermal conductivity, preferably aluminum. At least one fluid channel is tubular and has a contact surface with the contact element so as to establish good thermal contact therewith. The contact surface is preferably a plane wall of at least one fluid channel. At least one fluid channel is particularly preferably of a rectangular cross-section. The wall of at least one fluid channel is dimensionally stable. At least one fluid channel is also usually made of a metal with high thermal conductivity, preferably aluminum. In principle, multiple fluid channels can be connected in parallel or in a row in any desired manner. One or more fluid channels can be designed or arranged to have an overall serpentine shape.

[0014] Furthermore, at least one expansion element is elastically deformable to allow expansion. For example, the at least one expansion element can be made of a plastic or rubber material. During operation of the heat transfer device, the at least one expansion element expands under the action of fluid pressure, thereby pressing the at least one fluid channel against the at least one contact element. The at least one expansion element is then supported on a sufficiently stable support surface. The desired mechanical pressure of the at least one fluid channel against the at least one contact element can be determined by the number, arrangement, shape, or size of the expansion elements.

[0015] Furthermore, at least one expansion element is disposed on a support side of the at least one fluid channel, opposite the contact side, so as to press the at least one fluid channel against the at least one contact element via the support surface. Thus, the entire at least one fluid channel is pressed against the at least one contact element via the support surface. This prevents changes in the cross-sectional area of the at least one fluid channel, thereby preventing the flow of fluid through the at least one fluid channel from being affected.

[0016] Furthermore, at least one fluid channel has at least one groove on its channel wall, and at least one expansion element is disposed in the groove of the channel wall and is designed to expand when the at least one fluid channel is pressurized. For example, the at least one expansion element can be inserted into the groove.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The fluid pressure available in the heat transfer device can be used to generate a pressure of the at least one fluid channel on the contact element, ensuring surface-to-surface heat transfer without the need for mechanical spring elements to generate the contact pressure. Since the at least one fluid channel is only pressed against the contact element during use, the mechanical load is reduced. Therefore, the fluid channel is not subjected to mechanical loads when not in use, and the same applies to the supporting surface supported by the expansion element and the components mechanically connected thereto. Therefore, compared with the use of elastic spring elements, the mechanical load is only applied temporarily, which is particularly advantageous when using plastic components, which are prone to creep and permanent deformation when subjected to permanent mechanical loads. Improving the pressure of the at least one fluid channel on the contact element can also reduce the thickness of the contact element, thereby reducing the thermal resistance between the at least one fluid channel and the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a structural diagram of a multi-protection liquid-cooled battery pack structure and system embodiment of the present invention; Figure 2 This is a second structural diagram of a multi-protection liquid-cooled battery pack structure and system embodiment of the present invention; Figure 3 This is a partial structural diagram of a multi-protection liquid-cooled battery pack structure and system embodiment of the present invention; Figure 4 This is a second partial structural diagram of an embodiment of a multi-protection liquid-cooled battery pack structure and system of the present invention; The reference numerals in the drawings of the specification include: Battery 1, battery housing assembly 2, battery cell 3, battery housing 4, interior 5, heat transfer device 6, fluid channel 7, fluid 8, contact element 9, contact side 10, expansion element 11, support side 12, groove 13, free wall 14, projection 15, support surface 16, bottom wall 17, bypass line 18, inlet 19, outlet 20, flange area 21. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand the present invention, the technical solution of the present invention is further described below with reference to the accompanying drawings and embodiments:

[0021] It should be noted that the same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "inside", "outside", etc. appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0022] In addition, the terms "first," "second," and so on, used in this disclosure are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, features specified as "first" or "second" may explicitly or implicitly include at least one of these features.

[0023] In the description of the present invention, unless otherwise clearly specified and limited, if the term "connection" appears to indicate the connection relationship between components, the term should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal connection of two components or the interaction relationship between two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0024] Example 1

[0025] like Figure 1-4 As shown, the liquid-cooled battery 1 includes a battery housing assembly 2 and a plurality of battery cells 3. The battery housing assembly 2 includes a battery housing 4, which is used to enclose an internal space 5 for accommodating the battery cells 3. The battery housing 4 in the first embodiment is made of lightweight plastic or composite material.

[0026] The battery housing assembly 2 also includes a heat transfer device 6 having an inlet, an outlet and a plurality of fluid channels 7, which are arranged between the inlet, outlet and outlet in a fluid manner. The fluid channels 7 are tubular and have a rectangular cross section. The walls of the fluid channels 7 are made of a metal with high thermal conductivity (preferably aluminum) and are dimensionally stable. The fluid channels 7 can be connected in parallel or in a row in principle in any manner. The fluid channels 7 are arranged in the interior 5. The fluid channels 7 can be fixedly mechanically connected to each other. Alternatively, each fluid channel 7 can be arranged to be movable relative to each other.

[0027] Fluid 8 flows from the inlet through the heat transfer device 6 to the outlet via the fluid channel 7. In this embodiment, fluid 8 is a gas, or preferably a liquid. Fluid channel 7 is located within the interior 5. The inlet and outlet can lead to the battery housing 4 or can be located within the battery housing 4, for example, to distribute fluid 8 within the battery housing 4.

[0028] Liquid-cooled battery 1 also includes contact element 9, whose bottom surface is in thermal contact with contact side 10 of fluid channel 7, allowing heat transfer between contact element 9 and fluid channel 7. In this embodiment, contact element 9 is made of a metal with high thermal conductivity, preferably aluminum. Contact side 10 of fluid channel 7 contacts contact element 9 to establish good thermal contact therewith. Contact side 10 represents the planar wall of the corresponding fluid channel 7. Furthermore, contact element 9 is in thermal contact with battery cells 3 to transfer heat.

[0029] The fluid channels 7 together form a heat exchanger, absorbing heat from or releasing heat to the contact elements 9, depending on the operating conditions of the heat transfer device 6. This allows the temperature of the battery cells 3 to be controlled for optimal operation and maximum storage capacity. Heat is thus transferred from the fluid 8 via the fluid channels 7 and contact elements 9 to the battery cells 3, and vice versa. Thus, the contact elements 9 serve to transfer heat between the fluid channels 7 and the battery cells 3.

[0030] Figure 1 A plurality of expansion elements 11 are formed in the fluid channel 7. The expansion elements 11 are elastically deformable, thereby achieving expansion. The expansion elements 11 can be made of, for example, elastic plastic or elastic rubber. To this end, two rows of expansion elements 11 having grooves 13 are provided on the support side 12 opposite to the contact side 10 in the fluid channel 7. The grooves 13 and the expansion elements 11 are both circular, as shown in the figure. Figure 2 .

[0031] The expansion element 11 is inserted into the groove 13 from the inside of the fluid channel 7. The expansion element 11 abuts the fluid channel 7 from the inside via the flange area 21 and can extend through the groove 13 even when the fluid 8 is not pressurized.

[0032] The expansion element 11 is inserted into the groove 13 from the inside of the fluid channel 7. The expansion element 11 abuts the fluid channel 7 from the inside via the flange area 21 and can extend through the groove 13 even when the fluid 8 is not pressurized.

[0033] The pressure increase in the fluid channel 7, i.e. the pressurization of the fluid 8, causes the expansion element 11 to expand, as shown in the figure Figure 1 The free wall 14 not adjacent to the relevant fluid channel 7 is arched outward due to pressure, as shown in the figure Figure 1 Expansion element 11 for the right side.

[0034] The expansion of expansion element 11 forms protrusion 15. Due to the pressurization of fluid 8 in heat transfer device 6, expansion element 11 expands, thereby forming protrusion 15. In this embodiment, due to the pressurization of fluid 8, protrusion 15 expands to the inner surface 16 of bottom wall 17 of battery housing 4, causing protrusion 15, fluid channel 7, and heat transfer device 6 to abut against inner surface 16. Therefore, inner surface 16 of bottom wall 17 forms a support surface 16 for fluid channel 7.

[0035] Because fluid channel 7 is supported on support surface 16, expansion element 11 presses fluid channel 7 toward contact element 9 when fluid 8 is pressurized. This improves thermal contact between contact element 9 and fluid channel 7, and between contact element 9 and battery cell 3. The dimensionally stable design of fluid channel 7 prevents changes (especially reductions) in its cross-sectional area, thereby preventing the circulation of fluid 8 in fluid channel 7 from being affected.

[0036] The expansion element 11 expands only when the fluid 8 is pressurized, thereby pressing the fluid channel 7 toward the contact element 9 through the pressure generated by the fluid pressure. The mechanical load on the bottom wall 17 is correspondingly reduced, thereby reducing deformation of the battery housing 4, particularly the bottom wall 17. At the same time, the expansion element 11 fits tightly against the inner surface 16 of the bottom wall 17, thereby reliably pressing the fluid channel 7 toward the contact element 9. In addition, the weight of the battery cell 3 generates a reaction force, thereby achieving particularly reliable thermal contact between the contact element 9 and the fluid channel 7.

[0037] A large number of expansion elements 11 generally allows for a very precise adaptation of the support surface 16, even if the support surface deforms, for example, during operation. Depending on the shape of the fluid channel 7 and the recess 13, a uniform pressing of the fluid channel 7 against the contact element 9 can be achieved. By setting the number of expansion elements 11 and their shape or size, the desired mechanical pressure of the fluid channel 7 against the contact element 9 can be set. Furthermore, due to the expansion of the expansion elements 11, component tolerances and deformations can be automatically compensated during loaded operation (i.e., when the fluid 8 is pressurized).

[0038] Example 2

[0039] Figure 3 Regarding the liquid-cooled battery 1 and battery housing assembly 2 according to the second embodiment, the liquid-cooled battery 1 and battery housing assembly 2 of the second embodiment substantially correspond to those of the first embodiment. Therefore, only the differences between the liquid-cooled battery 1 and battery housing assembly 2 of the first and second embodiments will be described below. Further details of the liquid-cooled battery 1 and battery housing assembly 2 of the second embodiment correspond to those of the first embodiment.

[0040] The liquid-cooled battery 1 and battery housing assembly 2 of the second embodiment differ from those of the first embodiment in the arrangement and structure of the grooves 13 and expansion elements 11. In the second embodiment, the fluid channel 7 has only one row of grooves 13, each containing an expansion element 11. Unlike the first embodiment, both the grooves 13 and expansion elements 11 are rectangular.

[0041] Example 3

[0042] Figure 4 The present invention relates to a liquid-cooled battery 1 and battery housing assembly 2 according to a third embodiment. The liquid-cooled battery 1 and battery housing assembly 2 of the third embodiment are substantially the same as those of the first or second embodiment, and therefore only the differences between the first and third embodiments are described below. Further details of the liquid-cooled battery 1 and battery housing assembly 2 of the third embodiment correspond to those of the first or second embodiment.

[0043] The liquid-cooled battery 1 and battery housing assembly 2 of the third embodiment include multiple fluid channels 7, but these channels do not have any grooves 13. Unlike the first embodiment, in the second embodiment, multiple expansion elements 11 are positioned between the fluid channels 7 and the support surface 16. The expansion elements 11 are designed in a balloon or pillow-like shape, interconnected by bypass lines 18, and arranged parallel to the fluid channels 7. The expansion elements 11 are in fluid communication with the inlet 19 and outlet 20 of the heat transfer device 6 via the bypass lines 18. The cross-sectional area of the bypass lines 18 is smaller than that of the fluid channels 7.

[0044] In an alternative embodiment that can be combined with the first to third embodiments, a plurality of contact elements 9 are provided for heat transfer with the battery cells 3, preferably one contact element 9 is provided for each battery cell 3. The contact side 10 of the fluid channel 7 can be pressed against the plurality of contact elements 9. Particularly preferably, each fluid channel 7 can be pressed against one of the contact elements 9.

[0045] The above is only an embodiment of the present invention. Common knowledge such as the specific structure and characteristics of the scheme is not described in detail here. Ordinary technicians in the relevant field are aware of all common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the guidance of this application. Some typical well-known structures or well-known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention. These will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A multi-protection liquid-cooled battery pack structure, characterized by: A battery housing is provided for enclosing an interior space accommodating a plurality of battery cells; And a heat transfer device having an inlet, an outlet and at least one fluid channel arranged between the inlet and the outlet, wherein a fluid flows from the inlet through the heat transfer device to the outlet via the at least one fluid channel, wherein: at least one of the fluid channels is arranged in the internal space, and a contact side of at least one of the fluid channels can be pressed against at least one contact element in contact with a plurality of battery cells to transfer heat, and a plurality of expansion elements are arranged on a support side of the at least one fluid channel opposite to the contact side.

2. The multi-protection liquid-cooled battery pack structure according to claim 1, characterized in that: At least one of the fluid channels has at least one groove in a wall thereof, and a plurality of the expansion elements are disposed in one of the grooves in the wall.

3. The multi-protection liquid-cooled battery pack structure according to claim 2, characterized in that: An expansion element is provided in each of the plurality of grooves, and the plurality of grooves and the plurality of expansion elements are arranged in at least one row, and the grooves are circular or rectangular.

4. The multi-protection liquid-cooled battery pack and system according to claim 3, characterized in that: The expansion element is located between at least one fluid channel and a support surface; and a plurality of the expansion elements are in fluid communication with the inlet, the outlet, and or at least one fluid channel; The plurality of contact elements are in heat transfer with the plurality of battery cells, each battery cell has one contact element, and the contact side of at least one fluid channel can be pressed against the plurality of contact elements; The respective contact sides of a plurality of the fluid channels may be pressed against at least one of the contact elements.

5. The multi-protection liquid-cooled battery pack structure according to claim 4, characterized in that: A support plate is provided in the battery housing, the surface of the support plate is a support surface, and the support plate forms a middle wall of the battery housing.

6. The multi-protection liquid-cooled battery pack structure according to claim 5, characterized in that: The heat transfer device includes a first heat transfer device and a second heat transfer device. The plurality of battery cells are arranged in at least two layers. The first heat transfer device is assigned to the first layer of the at least two layers, and the second heat transfer device is assigned to the second layer of the at least two layers. The corresponding contact side of each fluid channel of the first heat transfer device and the second heat transfer device can be pressed against at least one corresponding contact element of the plurality of battery cells to transfer heat.

7. A multi-protection liquid-cooled battery pack system, characterized by: comprising a plurality of battery cells and at least one contact element; And a battery housing assembly, comprising: a battery housing, which surrounds an interior for receiving a plurality of battery cells; and a heat transfer device, which has an inlet, an outlet and at least one fluid channel in which a fluid is arranged between the inlet and the outlet, wherein the fluid flows from the inlet to the outlet through the heat transfer device via the at least one fluid channel to transfer heat between the at least one fluid channel and the plurality of battery cells, wherein the at least one fluid channel is arranged in the interior, and a contact side of the at least one fluid channel can be pressed against at least one contact element to transfer heat, and wherein a plurality of expansion elements are arranged on a support side of the at least one fluid channel opposite to the contact side, and the plurality of expansion elements press the at least one fluid channel against the at least one contact element by being supported on a support surface.

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