Battery pack having single cells cooled by cooling fins of a heat sink structure

Abstract

The present invention relates to a battery pack (1), comprising cooling fins (2), single cells (3a, 3b, 3c, 3d) for generating electric current, assembly rods (4) for the single cells (3a, 3b, 3c, 3d), and inlet manifolds (5) and outlet manifolds (6) for a cooling fluid flowing in the cooling fins (2). The cooling fins (2) are arranged in a plurality of parallel rows, each row extending from the inlet manifold (5) to the outlet manifold (6), two single cells (3a, 3b) are associated with the cooling fins (2) between each pair of two adjacent assembly rods (4), and the two single cells (3a, 3b) extend parallel to the associated cooling fins (2).

Description

Technical Field

[0001] The present invention relates to a battery pack having single cells cooled by cooling fins, the battery pack adopting a heat sink structure for arranging constituent elements of the battery pack opposite to each other. Background Art

[0002] Today, there are three types of cells: prismatic cells, cylindrical cells and so-called propulsion cells. For all three, the assembly technology is always similar. Small numbers of cells are assembled in modules, these modules are then assembled together with a cooling system, and finally all the modules are assembled in an assembly that forms a battery pack.

[0003] The first major problem with this approach is volume, as a bulky structure is placed around the small group of cells. This structure takes up space and, because assembly-related constraints dictate that there must be gaps between modules, severely limiting the number of cells that can be loaded into the battery assembly.

[0004] The second problem is in the area of ​​cooling, where, primarily due to the structure of the module, there is little contact between the individual cells and the cooling system, typically cooling fins.

[0005] This can be Figure 1 It can be seen in. Figure 1 A battery pack 1a according to the prior art is shown. The battery pack 1a includes a cooling fin 2, single cells 3a, 3b, 3c, 3d for generating current, an assembly rod 4 for the single cells 3a, 3b, 3c, 3d, and an inlet manifold 5 and an outlet manifold 6 for a coolant 6 flowing through the cooling fin 2. The battery pack 1a has an outer structure 8 surrounding the battery pack 1a and a reinforcing member 9 inside the battery pack 1a.

[0006] Document US-A-2011 / 162820 describes a battery pack having a cooling fin and a plurality of single cells. The cooling fin includes cooling fins having a substantially flat surface. The cooling fin includes a frame adjacent to the cooling fins and forming a node with the cooling fins adjacent to the periphery of the cooling fin. The frame and the cooling fins define at least one liquid inlet, at least one liquid outlet, and a flow channel therebetween.

[0007] The liquid inlet and the liquid outlet are arranged in a node-through manner and are in fluid communication with the flow channel. The flow channel is arranged near the perimeter and is in heat transfer with the substantially flat surface of the cooling fin.

[0008] However, this document does not describe how the cells are positioned relative to the cooling fins, and in particular the number of cells assigned to each cooling fin.

[0009] The problem underlying the present invention is therefore to arrange, for a battery pack comprising cells, assembly rods, cooling fins between inlet and outlet manifolds, at least these elements relative to one another in order to increase the number of cells integrated in the battery pack while ensuring optimal cooling of the cells. Summary of the invention

[0010] To achieve this object, a battery pack is provided according to the present invention, comprising cooling fins, single cells for generating current, assembly rods for the single cells, and inlet manifolds and outlet manifolds for a coolant flowing through the cooling fins. The present invention is unique in that the cooling fins are distributed into a plurality of parallel rows, each row extending from the inlet manifold to the outlet manifold, two single cells are associated with the cooling fins between each pair of adjacent assembly rods, and the two single cells extend parallel to the associated cooling fins.

[0011] The technical effect of the present invention is to delete the external structure and internal reinforcement elements of the battery pack that occupy a large amount of space. The assembly of the battery pack is similar to the assembly of the radiator. The fins of the radiator are formed by the single battery, the cooling fins become the structure of the radiator and the main pipe becomes the crossbeam and longitudinal beam of the battery pack.

[0012] The solution proposed by the invention allows the integration of 20% to 30% more cells, thus allowing the capacity of the battery pack to be increased. The cooling is carried out directly on the cells and over a larger contact surface, which allows to withstand fast charging cycles of the battery pack of less than 20 minutes and dissipate more heat energy.

[0013] The battery pack is strong and resistant to shock and vibration, making it particularly suitable for loading in motor vehicles. The battery pack can help strengthen the vehicle's chassis.

[0014] The present invention is applicable to various single cells and can also be combined with modifications such as adding a thermal conductor such as thermally conductive glue between the single cell and the cooling fin.

[0015] Advantageously, the single cells are distributed in rows parallel to the rows formed by the cooling fins, and two single cells are interposed between two adjacent rows of cooling fins.

[0016] Advantageously, the ends of each row of cooling fins are welded or brazed, or preferably crimped, to the inlet and outlet manifolds.

[0017] In fact, crimping does not heat the cell and allows protecting the battery.

[0018] Advantageously, the assembly rod extends parallel to the inlet manifold and the outlet manifold, and perpendicular to the cooling fins and the single cells.

[0019] Advantageously, for each pair of two adjacent assembly rods, the positions of the two adjacent assembly rods are adjusted to apply pressure to a single cell pair consisting of two single cells and a portion of the cooling fins interposed between the two adjacent assembly rods.

[0020] Advantageously, the single cells each have a vent hole, and the assembly rod is drilled with vent holes corresponding to the vent holes.

[0021] Advantageously, each ventilation opening of the assembly bar is flush with a row of single cells.

[0022] Advantageously, the cooling fin comprises a plurality of coolant channels having a flat surface.

[0023] Advantageously, the cells are electrochemical cells.

[0024] The invention relates to a motor vehicle comprising at least one such battery pack. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Other characteristics, objectives and advantages of the invention will emerge on reading the following detailed description and with reference to the accompanying drawings, given as non-limiting examples, in which:

[0026] Figure 1 is a schematic diagram of a battery pack according to the prior art,

[0027] Figure 2 is a schematic diagram of a battery pack according to the present invention.

[0028] It should be understood that the drawings are given as examples and not as a limitation of the present invention. The drawings constitute a schematic diagram for promoting the understanding of the principles of the present invention and are not necessarily in scale with actual application. In particular, the sizes of the different elements shown do not reflect the facts. DETAILED DESCRIPTION

[0029] exist Figure 1 and Figure 2 In the figure, for simplicity, only a single assembly bar 4, a single vent 7, a single cooling plate 2, and two cells 3a, 3b associated to all two related cells are shown, but a description of one of these elements also applies to all equivalent elements.

[0030] Reference Figure 2 The present invention relates to a battery pack 1 comprising a cooling fin 2, single cells 3a, 3b, 3c, 3d for generating current, an assembly rod 4, and an inlet manifold 5 and an outlet manifold 6 for a cooling liquid, wherein advantageously but not exclusively, the main component of the cooling liquid is water circulating in the cooling fin 2, as indicated by the arrows.

[0031] According to the present invention, the cooling fins 2 are distributed in a plurality of parallel rows. Each row extends from the inlet manifold 5 to the outlet manifold 6 to ensure the circulation of the coolant in the battery pack 1.

[0032] Two cells 3a, 3b, advantageously cells 3a, 3b, 3c, 3d, storing and releasing electrochemical energy are associated with a cooling plate 2 between each pair of two adjacent assembly bars 4, the word "adjacent" meaning "adjacent". The two cells 3a, 3b extend parallel to the associated cooling plate 2.

[0033] In this example, assembly bars 4 are positioned on one of the two sides of each cooling fin 2 , but other architectures are also contemplated.

[0034] As in Figure 2 As shown in FIG, a single single cell 3d can be inserted between the assembly rod 4 closest to the inlet manifold 5 and the inlet manifold 5. The same can be applied to inserting a single cell 3c between the assembly rod 4 closest to the outlet manifold 6 and the outlet manifold 6.

[0035] The single cells 3a, 3b, 3c, 3d can be distributed in rows parallel to the rows formed by the cooling fins 2, wherein two single cells 3a, 3b are interposed between two adjacent or neighboring rows of cooling fins 2. Thus, a portion of the cooling fins 2 is dedicated to the two cells 3a, 3b, and the same is true for the rows formed by the cooling fins 2.

[0036] exist Figure 2 In the embodiment of the present invention, there are 15 cooling fins 2, 4 assembly rods 4, and 8 single cells 3a, 3b, 3c, 3d between two adjacent rows of cooling fins 2, that is, a total of 14 times 8 single cells 3a, 3b, 3c, 3d, that is, 112 single cells 3a, 3b, 3c, 3d. The rows formed by the single cells 3a, 3b, 3c, 3d and the rows formed by the cooling fins 2 extend along the length of the battery pack 1. All of this is not restrictive.

[0037] The end of each row of cooling fins 2 can be welded, brazed or crimped to the inlet manifold 5 or the outlet manifold 6 so that the circulation of the coolant is sealed.

[0038] The assembly rod 4 may extend parallel to the inlet manifold 5 and the outlet manifold 6, and perpendicular to the cooling fins 2 and the single cells 3a, 3b, 3c, 3d. Therefore, the battery pack 1 has a square or rectangular cross section. Figure 2 In the figure, the width of the battery pack 1 with a rectangular cross section supports the inlet manifold 5 or the outlet manifold of the coolant.

[0039] For each pair of two adjacent assembly rods 4 , the positions of the two adjacent assembly rods 4 can be adjusted to apply pressure to the single cell pair consisting of two single cells 3 a and 3 b and part of the cooling fin 2 interposed between the two adjacent assembly rods 4 .

[0040] exist Figure 2 In the embodiment, the assembly rods 4 extend across the width of the battery pack 1 and constrain the single cells 3a, 3b, 3c, 3d and portions of the cooling fins 2 inserted between the two assembly rods 4 to enhance the contact between the two single cells 3a, 3b and portions of the cooling fins 2.

[0041] exist Figure 2 As can be seen in the figure, the single cells 3a, 3b, 3c, 3d each have an exhaust hole, and the assembly rod 4 can be drilled with a vent 7. Advantageously, the vent 7 is regularly distributed corresponding to the exhaust hole. Figure 2 In the embodiment shown in FIG. 1 , each vent 7 of the assembly rod 4 can be flush with a row of single cells 3a, 3b, 3c, 3d. Figure 2 14 vents 7 are shown for each assembly rod 4, so the number of vents 7 is the same as the number of single cell pairs consisting of two single cells 3a, 3b. Therefore, when the single cells 3a, 3b, 3c, 3d are over-pressurized due to overheating, the vents 7 allow gas to escape.

[0042] For the two outermost assembly rods, each facing the inlet manifold 5 or the outlet manifold 6 at a certain distance from each other, a ventilation hole 7 facing a unique single cell 3c, 3d can also be configured. In each row of single cells 3a, 3b, 3c, 3d, the single cells 3c, 3d face the inlet manifold 5 or the outlet manifold 6.

[0043] The cooling plate 2 may include a plurality of coolant pipes in its interior, and advantageously, the coolant pipes have a flat surface.

[0044] The invention relates to a motor vehicle comprising at least one such battery 1 , for example a battery 1 of an onboard electrical system or a traction battery 1 for supplying an electric motor, the size and number of the individual cells 3a , 3b , 3c , 3d being different in both cases.

[0045] The invention is not limited by the embodiments described and shown which are given as examples only.

Claims

1. A battery pack (1), comprising cooling fins (2), single cells (3a, 3b, 3c, 3d) for generating electric current, assembly rods (4) for the single cells (3a, 3b, 3c, 3d), and an inlet manifold (5) and an outlet manifold (6) for a coolant flowing in the cooling fins (2), wherein the cooling fins (2) are arranged in a plurality of parallel rows, each row extending from the inlet manifold (5) to the outlet manifold (6), two single cells (3a, 3b) are associated with the cooling fins (2) between each pair of two adjacent assembly rods (4), and the two single cells (3a, 3b) extend parallel to the associated cooling fins (2), wherein the assembly rod (4) extends parallel to the inlet manifold (5) and the outlet manifold (6), and is perpendicular to the cooling fins (2) and the single cells (3a, 3b, 3c, 3d); and For each pair of two adjacent assembly rods (4), the positions of the two adjacent assembly rods (4) are adjusted to apply pressure to a single cell pair consisting of two single cells (3a, 3b) inserted between the two adjacent assembly rods (4) and part of the cooling fin (2). The single cells (3a, 3b, 3c, 3d) each have an exhaust hole, the assembly rod (4) is drilled with a vent (7) corresponding to the exhaust hole, and Each ventilation opening (7) of the assembly rod (4) is flush with a row of single batteries (3a, 3b, 3c, 3d).

2. The battery pack (1) according to claim 1, wherein the single cells (3a, 3b, 3c, 3d) are distributed in rows parallel to the rows formed by the cooling fins (2), and two single cells (3a, 3b) are inserted between two adjacent rows of cooling fins (2).

3. The battery pack (1) according to claim 2, wherein the end of each row of cooling fins (2) is welded to the inlet manifold (5) or the outlet manifold (6).

4. The battery pack (1) according to claim 3, wherein the end of each row of cooling fins (2) is crimped to the inlet manifold (5) or the outlet manifold (6).

5. The battery pack (1) according to claim 1, wherein the cooling fin (2) comprises a plurality of coolant pipes having a flat surface.

6. The battery (1) according to any one of the preceding claims, wherein the single cells (3a, 3b, 3c, 3d) are electrochemical single cells.

7. A motor vehicle comprising at least one battery pack (1) according to any one of the preceding claims.

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