Battery pack cooling system

Abstract

To improve temperature variations among battery cells in a battery stack where multiple battery cells are stacked, when a high temperature occurs in one battery cell. [Solution] A cooling system 1 for a battery pack 2 comprising a battery stack 4 and a case 5, comprising: a fin 15 that is positioned inside a first flow path 11 so as to face an air outlet 14a in the stacking direction and whose angle can be changed; a moving device 16 that moves the fin 15 in the stacking direction; and a control device that controls the fin 15 and the moving device 16. The fin 15 receives cooling air from the air outlet 14a and generates a flow of cooling air toward the battery cells 3. The control device adjusts the flow rate of cooling air supplied to the battery cells 3 by changing the angle and position of the fin 15 based on signals input from a sensor that detects the temperature of each battery cell 3.

Description

Technical Field

[0001] The present invention relates to a cooling system for a battery pack.

Background Art

[0002] Patent Document 1 discloses a battery pack cooling system that suppresses unevenness in the flow rate of cooling air supplied to a battery stack by providing a ventilation portion in an exhaust chamber through which cooling air flows after cooling battery cells, and discharging the cooling air from the ventilation portion to the outside of the case.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the configuration described in Patent Document 1, although each battery cell can be cooled at a constant flow rate, in a battery stack, since the temperatures of the battery cells are different, when a high-temperature battery cell occurs, it is difficult to intensively cool the relatively high-temperature battery cells.

[0005] The present invention has been made in view of the above circumstances, and an object thereof is to provide a battery pack cooling system that can improve the variation in the temperatures of battery cells when a high-temperature battery cell occurs in a battery stack in which a plurality of battery cells are stacked.

Means for Solving the Problems

[0006] The present invention relates to a cooling system for a battery pack comprising a battery stack in which a plurality of battery cells are stacked, and a case housing the battery stack, wherein the system includes: a first flow path provided inside the case below the battery stack, through which cooling air supplied from outside the case flows in the stacking direction of the battery stack; a cooling flow path provided between adjacent battery cells in the stacking direction, through which cooling air flowing in from the first flow path cools the battery cells; a second flow path provided inside the case above the battery stack, through which cooling air flowing out from the cooling flow path flows in the stacking direction so as to be discharged to the outside of the case; and an air outlet opening into the first flow path, wherein the air outlet The device comprises a cooling blower that supplies cooling air to the first flow path in the stacking direction, a fin that is positioned inside the first flow path so as to face the air outlet in the stacking direction and whose angle can be changed, a moving device that moves the fin in the stacking direction, and a control device that controls the fin and the moving device, wherein the fin, when its angle becomes an inclined angle, receives the cooling air from the air outlet and generates a flow of cooling air toward the battery cells, and the control device adjusts the flow rate of cooling air supplied to the battery cells by changing the angle and position of the fin based on a signal input from a sensor that detects the temperature of each battery cell. [Effects of the Invention]

[0007] In this invention, when a high temperature occurs in a battery stack in which multiple battery cells are stacked, the temperature variation of each battery cell can be improved. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram showing the cooling system of the battery pack in an embodiment. [Figure 2] This is a schematic diagram showing the fins in a folded state. [Modes for carrying out the invention]

[0009] The following describes in detail the cooling system for the battery pack in the embodiments of the present invention. However, the present invention is not limited to the embodiments described below.

[0010] Figure 1 is a schematic diagram showing a battery pack cooling system in an embodiment. Cooling system 1 is an air-cooled cooling system that targets a battery pack 2 mounted on a vehicle and air-cools the battery cells 3 contained in the battery pack 2. The battery pack 2 comprises a battery stack 4 in which multiple battery cells 3 are stacked, and a case 5 that houses the battery stack 4. The battery stack 4 is a battery pack in which multiple battery cells 3 are stacked. In the battery stack 4, separators are placed between adjacent battery cells 3 in the stacking direction, and the battery cells 3 and separators are stacked alternately. The separators are provided with flow path forming sections that form cooling flow paths 13. Cooling air flows between adjacent battery cells 3 in the battery stack 4.

[0011] The cooling system 1 comprises a first flow path 11, a second flow path 12, a cooling flow path 13, a cooling blower 14, fins 15, a moving device 16, and a control device.

[0012] The first channel 11 is an upstream channel located below the battery stack 4 inside the case 5. As shown in Figures 1 and 2, cooling air supplied from outside the case 5 to cool the battery cells 3 flows through the first channel 11 in the stacking direction of the battery stack 4. In Figures 1 and 2, the flow of the cooling air is indicated by arrows. In this explanation, the stacking direction of the battery stack 4 may be simply referred to as the stacking direction.

[0013] The second channel 12 is a downstream channel located above the battery stack 4 inside the case 5. Inside the second channel 12, the cooling air that has cooled the battery cells 3 flows outwards from the case 5 in the stacking direction.

[0014] The cooling channel 13 is a heat exchange channel provided between adjacent battery cells 3 in the stacking direction. The cooling channel 13 is formed by the battery cells 3 and the separator. Inside the cooling channel 13, cooling air flows from bottom to top so that the cooling air that flows in from the first channel 11 cools the battery cells 3 and flows out into the second channel 12.

[0015] The cooling blower 14 is a fan attached to the case 5 and supplies cooling air to the inside of the case 5. The cooling blower 14 has an air outlet 14a that faces the stacking direction and opens into the first flow path 11. The air outlet 14a supplies cooling air that flows into the first flow path 11 in the stacking direction.

[0016] The fin 15 is provided in the first flow path 11 and is a fin whose angle can be changed. The fin 15 is positioned inside the first flow path 11 so as to face the air outlet 14a in the stacking direction. The fin 15 can change its angle so that it receives the cooling air flowing from the air outlet 14a in the stacking direction and directs the cooling air toward the bottom surface of the battery cell 3. In other words, when the angle of the fin 15 is at a predetermined inclination angle, it receives the cooling air from the air outlet 14a and generates a flow of cooling air toward the battery cell 3. The fin 15 has a flat blade portion and a pivot point portion that swings the blade portion, and the blade portion swings relative to the stacking direction around the pivot point portion. The blade portion is the part that receives the cooling air from the air outlet 14a.

[0017] The moving device 16 is a device that moves the fins 15 in the stacking direction. For example, the moving device 16 is made up of a belt conveyor, and the pivot point of the fins 15 is attached to the belt conveyor. The moving device 16 can move the fins 15 in the stacking direction so that the position of the fins 15 relative to the air outlet 14a changes, as does the position of the fins 15 relative to the battery cells 3.

[0018] The control device is an electronic control device that controls the fins 15 and the moving device 16. The control device is configured to include a microcomputer having a CPU, a RAM, a ROM, and an input / output interface. Signals from various sensors mounted on the vehicle are input to the control device. For example, a signal from a temperature sensor that detects the temperature of each battery cell 3 in the battery pack 2 is input to the control device. The control device executes various controls based on the signals input from the various sensors.

[0019] The control device detects the variation in the temperature of each battery cell 3 in the battery stack 4 based on the signal input from the temperature sensor. Further, the control device adjusts the flow rate of the cooling air supplied to the battery cell 3 by changing the angle and position of the fins 15 based on the signal input from the temperature sensor that detects the temperature of the battery cell 3.

[0020] As shown in FIG. 1, when a high-temperature battery cell 3A is generated, the control device changes the position and angle of the fins 15 so that the flow rate of the cooling air supplied to the high-temperature battery cell 3A becomes relatively large. At that time, the moving device 16 moves the fins 15 so that the flow rate of the cooling air supplied to the high-temperature battery cell 3A increases, and the fins 15 are in a posture having an inclination angle so that a flow of cooling air directed toward the cooling flow path 13 adjacent to the high-temperature battery cell 3A occurs. As a result, the flow rate of the cooling air supplied to the high-temperature battery cell 3A becomes relatively large, the temperature of the high-temperature battery cell 3 can be intensively reduced, and the variation in the temperature of the battery cells 3 in the battery stack 4 can be improved.

[0021] As shown in FIG. 2, when the variation in the temperature of each battery cell 3 is small, the control device controls to fold the fins 15 so that the air outlet 14a and the fins 15 do not face each other in the stacking direction.

[0022] As described above, according to the embodiment, since the position and angle of the fins 15 provided inside the battery pack 2 can be changed, the path of the cooling air can be controlled, and the variation in the temperature of each battery cell 3 can be reduced. When a high-temperature battery cell 3A occurs, by controlling the angle and position of the fins 15, the flow rate of the cooling air supplied to the high-temperature battery cell 3A can be made larger than the flow rate to the other battery cells 3, and it can be adjusted to an appropriate cooling air flow rate.

Explanation of Reference Numerals

[0023] 1 Cooling system 2 Battery pack 3 Battery cell 4 Battery stack 5 Case 11 First flow path 12 Second flow path 13 Cooling flow path 14 Cooling blower 14a Air outlet 15 Fin 16 Moving device

Claims

1. A battery stack consisting of multiple battery cells stacked on top of each other, A case for housing the aforementioned battery stack, A cooling system for a battery pack, comprising: A first channel is provided inside the case below the battery stack, through which cooling air supplied from outside the case flows in the stacking direction of the battery stack, A cooling channel is provided between adjacent battery cells in the stacking direction, and cooling air flowing in from the first channel cools the battery cells, A second channel is provided inside the case above the battery stack, and flows in the stacking direction so that the cooling air flowing out from the cooling channel is discharged to the outside of the case, A cooling blower having an air outlet that opens into the first flow path, and supplying cooling air from the air outlet to the first flow path in the stacking direction, A fin is provided inside the first flow channel at a position that is able to face the air outlet in the stacking direction, and whose angle can be changed. A moving device for moving the fins in the stacking direction, A control device for controlling the fins and the moving device, Equipped with, The fins, when the angle becomes an inclined angle, receive the cooling air from the air outlet and generate a flow of cooling air toward the battery cell. The control device adjusts the flow rate of cooling air supplied to the battery cells by changing the angle and position of the fins based on signals input from sensors that detect the temperature of each battery cell. A cooling system for a battery pack characterized by the following features.

2. If a high temperature occurs in the battery cell, the control device changes the position and angle of the fins so that cooling air is supplied to the high-temperature battery cell, and the flow rate of the cooling air supplied to the high-temperature battery cell becomes relatively higher. The cooling system for a battery pack according to feature 1.

3. If the temperature variation of each battery cell is small, the control device folds the fins so that they do not face the air outlet. The battery pack cooling system according to feature 2.

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