JP-2026075482-A - Method for manufacturing a cooler and battery pack

JP2026075482AJP 2026075482 AJP2026075482 AJP 2026075482AJP-2026075482-A

Abstract

[Problem] To prevent the coolant flow path from being crushed when the battery is in use, while also preventing the battery from moving in the height direction when the thickness of the cooler changes. [Solution] A cooler disposed inside a case for housing batteries, having a cooling section disposed between adjacent batteries in the stacking direction, the cooling section having a plurality of ribs that extend to connect the first inner surface of the first cooling surface and the second inner surface of the second cooling surface and are deformable in response to a change in the distance between the first inner surface and the second inner surface, the plurality of ribs include a pair of ribs that deform to move away from each other when the distance between the first inner surface and the second inner surface changes in the direction of widening, and deform to move closer to each other when the distance between the first inner surface and the second inner surface changes in the direction of narrowing, the pair of ribs come into contact with each other when the batteries expand and the distance between the first inner surface and the second inner surface narrows to a predetermined amount, and in that contact state the ribs support each other so that the first inner surface and the second inner surface do not come any closer together. [Selection Diagram] Figure 1

Inventors

山下修

Assignees

トヨタ自動車株式会社

Dates

Publication Date: 20260508
Application Date: 20241022

Claims (5)

A cooler, which is placed inside a case that houses a battery and cools the battery, A stack of the batteries has a cooling section positioned between adjacent batteries in the stacking direction of the stack. The cooling unit is A flow path through which coolant flows in the width direction perpendicular to the stacking direction, A first cooling surface that contacts one of the aforementioned batteries, A second cooling surface that contacts the other of the aforementioned batteries, It has a plurality of ribs that extend to connect the first inner surface, which is the back surface of the first cooling surface, and the second inner surface, which is the back surface of the second cooling surface, and which are deformable in accordance with a change in the distance between the first inner surface and the second inner surface, The plurality of ribs include a pair of ribs that deform to move away from each other when the distance between the first inner surface and the second inner surface changes in a direction that widens, and deform to move closer to each other when the distance between the first inner surface and the second inner surface changes in a direction that narrows, The cooler is characterized in that the pair of ribs come into contact with each other when the battery expands and the distance between the first inner surface and the second inner surface narrows to a predetermined amount, and in that contact state, the ribs support each other so that the first inner surface and the second inner surface do not come any closer together.
The pair of ribs are, A first rib having a first contact portion, It includes a second rib that is positioned opposite the first rib and has a second contact portion that contacts the first contact portion, The first contact portion is located on the second rib side of the first connection point where the first rib is connected to the first inner surface, and the second connection point where the first rib is connected to the second inner surface. The second contact portion is located on the first rib side of the third connection point where the second rib is connected to the first inner surface, and the fourth connection point where the second rib is connected to the second inner surface. The cooler according to claim 1, characterized in that the pair of ribs come into contact with each other when the first contact portion and the second contact portion come into contact.
The cooler according to claim 2, characterized in that the length between the first connection point and the third connection point is shorter than the sum of the length from the first connection point to the first contact portion and the length from the third connection point to the second contact portion.
The cooler according to claim 3, characterized in that the length between the second connection point and the fourth connection point is shorter than the sum of the length from the second connection point to the first contact portion and the length from the fourth connection point to the second contact portion.
A method for manufacturing a battery pack comprising a cooler according to any one of claims 1 to 4, In a cooling device having a structure in which the coolers are arranged so that their cooling surfaces face each other, installed inside a case that houses multiple battery cells, the process includes an insertion step of inserting the battery cells between adjacent coolers, After the battery cells are inserted between the coolers, a deformation step is performed to deform the coolers by increasing the internal pressure of the coolers so that the cooling surface comes into contact with the battery cells. Includes, In the insertion process, the pair of ribs are separated from each other inside the cooler. A method for manufacturing a battery pack, characterized in that the deformation step includes a step of deforming the cooler so that the thickness of the cooler is increased, by deforming the pair of ribs so that they separate from each other, thereby displacing the cooling surface only in the stacking direction.

Description

This invention relates to a method for manufacturing a cooler and a battery pack. Patent Document 1 discloses a battery pack in which a cooling device for cooling the battery cells is provided inside a case that houses multiple battery cells. In the configuration described in Patent Document 1, the cooling device has multiple coolers, and the multiple coolers and multiple battery cells are stacked alternately. Patent Document 2 discloses the provision of pre-bent ribs inside a heat exchange tube through which a coolant flows. The shape of these ribs is either straight or curved, inclined relative to the main surface. Special Publication No. 2024-509489Special Publication No. 2016-537799 This is a schematic diagram showing the battery pack in the embodiment.This is a diagram illustrating a cooling system.This is a schematic diagram to explain a condenser.This is a cross-sectional view illustrating the cooling section.Figure 5(a) is a cross-sectional view illustrating the shape of the cooling section in the extruded state, and Figure 5(b) is a cross-sectional view illustrating the shape of the cooling section after the cooler has been deformed by the deformation process due to the application of pressure to the inside of the cooler.Figure 6(a) is a cross-sectional view illustrating the shape of the cooling section when the battery is in use, and Figure 6(b) is a cross-sectional view illustrating the state in which the battery cell expands when the battery is in use, causing a pair of ribs to support each other inside the cooling section. The following describes in detail the manufacturing methods of the cooler and battery pack according to embodiments of the present invention. However, the present invention is not limited to the embodiments described below. Figure 1 is a schematic diagram of a battery pack in an embodiment. The battery pack 1 comprises a plurality of battery cells 2, a case 3, and a cooling device 4. The battery pack 1 is mounted on an electric vehicle. The electric vehicle equipped with the battery pack 1 supplies the power stored in the battery pack 1 to the motor for propulsion. The battery cell 2 is a battery formed in a rectangular parallelepiped shape. The surface with the largest area of the battery cell 2 is the flat surface 2a. The battery cell 2 is arranged inside the case 3 with the flat surface 2a facing the X direction. Inside the case 3, multiple battery cells 2 are stacked in the X direction. The X direction is the same direction as the stacking direction of the stacked body of multiple battery cells 2. Case 3 is a battery pack case that houses the battery cells 2 and the cooling device 4. Inside Case 3, multiple battery cells 2 constitute a battery module. Case 3 can accommodate multiple battery modules. The cooling device 4 cools the battery cell 2 with a cooling liquid. The cooling device 4 comprises a cooler 20 and pipes 30. As shown in Figure 2, the cooling device 4 is an integrated structure in which multiple coolers 20 are joined to a pair of pipes 30. The cooler 20 is stacked alternately with the battery cells 2 to cool the battery cells 2. The cooler 20 is made of extruded metal. The cooler 20 extends in the Y direction. The Y direction is perpendicular to the X direction. The Y direction is the same direction as the width direction of the battery cells 2. The width direction is perpendicular to the stacking direction. The cooler 20 has a cooling surface 20a that contacts the battery cells 2. The cooling device 4 has a structure in which the coolers 20 face each other with their cooling surfaces 20a facing each other. The cooling surface 20a contacts the flat surface 2a of the battery cells 2. Pipe 30 is a rectangular pipe extending in the X direction. Pipe 30 is made of extruded metal. Multiple coolers 20 are connected to pipe 30. As shown in Figure 1, in the completed state of the battery pack 1, a laminate is formed inside the case 3 in which multiple coolers 20 and multiple battery cells 2 are alternately stacked in the X direction, with coolers 20 located at both ends of the stacking direction of the laminate. The stacking direction is the same as the X direction. Since the battery cells 2 are rectangular and the coolers 20 are flat, one battery cell 2 is sandwiched between two coolers 20. The battery cells 2 and coolers 20 are stacked so that the surface with the largest surface area among multiple surfaces is in contact. The cooling surface 20a includes a first cooling surface 20b that contacts one of the adjacent battery cells 2 and a second cooling surface 20c that contacts the other of the adjacent battery cells 2. Note that when the first cooling surface 20b and the second cooling surface 20c are not specifically distinguished, they are referred to as cooling surface 20a. The cooler 20 has a cooling section 21 and a connecting section 22. In the cooler 20, the cooling section 21 includes a cooling surface 20a, while the connecting section 22 does not include