Battery pack having novel cooling structure

Abstract

Disclosed is a battery pack having a plurality of battery cells or unit modules (unit cells), which can be charged and discharged, mounted in a pack case, wherein the unit cells are stacked in a direction (a Z direction) in which the unit cells are sequentially stacked in parallel to a ground in a state in which a spacing distance for coolant flow is provided between the respective unit cells to constitute a battery module, two or more battery modules are arranged in a horizontal direction (an X direction) on the plane with respect to a coolant introduction direction in which a coolant is introduced through a coolant inlet port in a state in which flow of the coolant between the battery modules is restrained to constitute a battery module group.

Claims

1. A battery pack having a plurality of battery cells or unit modules (unit cells), which can be charged and discharged, mounted in a pack case, wherein the unit cells are stacked in a direction (a Z direction) in which the unit cells are sequentially stacked in parallel to a ground in a state in which a spacing distance for coolant flow is provided between the respective unit cells to constitute a battery module, two or more battery modules are arranged in a horizontal direction (an X direction) on the plane with respect to a coolant introduction direction in which a coolant is introduced through a coolant inlet port in a state in which flow of the coolant between the battery modules is restrained to constitute a battery module group, the pack case is provided with a flow space (a coolant introduction part) extending from the coolant inlet port to the battery module group and another flow space (a coolant discharge part) extending from the battery module group to a coolant outlet port, and a coolant flow channel defined between the coolant introduction part and the coolant discharge part is configured to have a structure in which the coolant, introduced through the coolant introduction part, cools the battery modules while passing through the specific battery modules in a vertical direction (a Y direction) on the plane and is discharged through the coolant discharge part, and wherein an inside of one side of the coolant introduction part facing one side of the battery module group is configured to have a structure in which a distance between the inside of one side of the coolant introduction part and one side of the battery module group is decreased toward an end opposite to the coolant inlet port in a stepwise pattern.

2. The battery pack according to claim 1, wherein the battery pack is configured to have a structure in which a width (a vertical width) of the battery pack is twice or more a height of the battery pack.

3. The battery pack according to claim 1, wherein the coolant inlet port and the coolant outlet port are located at the same side or opposite sides of the pack case.

4. The battery pack according to claim 1, wherein the coolant inlet port and the coolant outlet port are formed in a symmetrical or asymmetrical fashion in the horizontal direction (the X direction) on the plane.

5. The battery pack according to claim 1, wherein the battery module group comprises battery modules groups (a left battery module group and a right battery module group) arranged at opposite sides on the plane from the coolant introduction part, and the coolant flow channel diverges in the horizontal direction (the X direction) W on the plane so that the coolant can be introduced into the left battery module group and the right battery module group.

6. The battery pack according to claim 1, wherein two or more of the battery modules are arranged in the vertical direction (the Y direction) on the plane.

7. The battery pack according to claim 6, wherein the battery modules are continuously arranged in a state in which the coolant flow channels corresponding to the respective battery modules communicate with each other.

8. The battery pack according to claim 6, wherein the coolant introduction part comprises two or more coolant introduction parts formed in the vertical direction (the Y direction) on the plane.

9. The battery pack according to claim 8, wherein the coolant flow channels of the coolant introduction parts diverge from the coolant inlet port.

10. The battery pack according to claim 6, wherein the coolant introduction part comprises coolant introduction part formed at the respective battery modules arranged in the vertical direction (the Y direction) on the plane.

11. The battery pack according to, claim 1, wherein an electronic member is further installed in an internal space of the pack case defined by the stepwise pattern of the inside of one side of the coolant introduction part.

12. The battery pack according to claim 1, wherein each of the battery cells is a lithium ion secondary battery, a lithium ion polymer secondary battery, or a nickel metal hydride secondary battery.

13. The battery pack according to claim 1, wherein the coolant is air.

14. A vehicle comprising a battery pack according to claim 1 as a power source.

15. The vehicle according to claim 14, wherein the vehicle is an electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

(2) FIG. 1 is a plan view typically showing a battery pack according to an embodiment of the present invention;

(3) FIG. 2 is a front view typically showing a battery module of FIG. 1;

(4) FIG. 3 is a perspective view showing a battery module group of FIG. 1;

(5) FIGS. 4 to 8 are plan views typically showing battery packs according to various embodiments of the present invention; and

(6) FIG. 9 is a perspective view of FIG. 8.

BEST MODE

(7) Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted, however, that the scope of the present invention is not limited by the illustrated embodiments.

(8) FIG. 1 is a plan view typically showing a battery pack according to an embodiment of the present invention, FIG. 2 is a front view typically showing a battery module of FIG. 1, and FIG. 3 is a perspective view typically showing a battery module group of FIG. 1. For convenience of understanding, the battery module group is shown as being erected with respect to the ground in FIG. 3.

(9) Referring to these drawings, a battery pack 100 includes battery module groups 30 and 40 arranged in a horizontal direction (an X direction) W on the plane with respect to a coolant introduction direction in which a coolant is introduced through coolant inlet ports 20, and pack cases 70 having flow spaces, i.e. coolant introduction parts 50, extending from the coolant inlet ports 20 to the battery module groups 30 and 40 and flow spaces, i.e. coolant discharge parts 60, extending from the battery module groups 30 and 40 to coolant outlet ports 22.

(10) Specifically, 16 battery modules 10 constitute a left battery module group 30 and a right battery module group 40 at opposite sides on the plane from the coolant introduction parts 50 in the horizontal direction (the X direction) W on the plane in a state in which flow of the coolant is restrained. Coolant flow channels diverge from the coolant introduction parts 50 in the horizontal direction (the X direction) W on the plane so that the coolant can be introduced into the left battery module group 30 and the right battery module group 40.

(11) Also, each of the battery module groups 30 and 40 is configured so that the battery modules 10 are continuously arranged in a vertical direction (a Y direction) L on the plane in pairs in a state in which the coolant flow channels communicate with each other.

(12) Consequently, the battery pack 100 is generally configured to have a structure in which the width L of the battery pack 100 is twice or more the height H of the battery pack 100.

(13) The coolant flow channels between the coolant introduction parts 50 and the coolant discharge parts 60 are configured to have a structure in which the coolant, introduced through the coolant introduction parts 50, cools the battery modules 10 while passing through the battery modules 10 in the vertical direction (the Y direction) L on the plane and is discharged through the coolant discharge parts 60. The coolant flow channels of the coolant introduction parts 50 diverge from the coolant inlet ports 20, and therefore, the coolant introduction parts 50 are substantially formed with respect to the battery modules 10 arranged in the vertical direction (the Y direction) L on the plane.

(14) The coolant inlet ports 20 and the coolant outlet ports 22 are disposed at opposite sides of the pack cases 70. The coolant inlet ports 20 and the coolant outlet ports 22 are formed in a symmetrical fashion in the horizontal direction (the X direction) W on the plane.

(15) The inside of one side of the coolant introduction part 50 facing one side of each of the battery module groups 30 and 40 is configured to have a structure in which a distance d between the inside of one side of the coolant introduction part 50 and one side of each of the battery module groups 30 and 40 is decreased toward the end opposite to the coolant inlet port 20.

(16) Each of the battery modules 10 is configured to have a structure in which unit cells 12 are stacked in a direction (a Z direction) H in which the unit cells 12 are sequentially stacked in parallel to the ground in a state in which a spacing distance D for coolant flow is provided between the respective unit cells 12 (see FIG. 2).

(17) That is, the spacing distance between the respective unit cells 12 is parallel to the direction in which the flow channel extends. Although the coolant is not uniformly introduced to the outermost battery module 11 in the horizontal direction (the X direction) W on the plane, therefore, the deviation in temperature of the unit cells 12 in at least one of the battery modules 10 is uniform.

(18) FIGS. 4 to 8 are plan views typically showing battery packs according to various embodiments of the present invention.

(19) Referring to FIG. 4, a battery pack 101 is configured to have a structure in which two coolant introduction parts 52 and 53 are formed in a vertical direction (a Y direction) L on the plane, and a coolant is introduced into battery module groups arranged at opposite sides (a left side and a right side) of the coolant introduction parts 52 and 53 from the coolant introduction parts 52 and 53.

(20) Generally, the coolant introduction parts 52 and 53 are formed with respect to battery modules 10 in the vertical direction (the Y direction) L on the plane, and coolant discharge parts disposed at the middle region of the battery pack are adjacent to each other.

(21) In a battery pack 102 of FIG. 5, the inside of one side of a coolant introduction part 54 includes two continuous incline planes. The incline planes of the inside of one side of the coolant introduction part include a first incline plane 56a starting from the end opposite to a coolant inlet port 21 and a second incline plane 56b provided between the first incline plane 56a and the coolant inlet port 21 so that the second incline plane 56b has an inclination greater than that of the first incline plane 56a.

(22) Also, an electronic member 80 is further installed in an internal space of a pack case 72 defined by the inclined structure of the inside of one side of the coolant introduction part 54. As a result, it is possible for the battery pack to exhibit high space utilization.

(23) A battery pack 103 of FIG. 6 is identical in structure to the battery pack 101 of FIG. 4 except that the inside of one side of a coolant introduction part 55 is configured to have a structure in which the distance between the inside of one side of the coolant introduction part 55 and one side of a battery module group 32 is decreased toward the end opposite to a coolant inlet port 22 in a stepwise pattern 34.

(24) In a battery pack 104 of FIG. 7, a coolant inlet port 23 and a coolant outlet port 24 are formed in an asymmetrical fashion in a horizontal direction (an X direction) W on the plane. That is, a coolant introduction part 57 does not diverge so that a coolant can be supplied only to a specific battery module group through the coolant introduction part 57.

(25) FIG. 8 is a plan view typically showing a battery pack according to a further embodiment of the present invention, and FIG. 9 is a perspective view of FIG. 8.

(26) Referring to these drawings, a coolant inlet port 25 and a coolant outlet port 26 are located at the same side of a pack case 74. That is, a direction in which a coolant flows in a coolant discharge part 68 is opposite to a direction in which the coolant flows in a coolant introduction part 58 so that the coolant, introduced from the coolant introduction part 58, can pass through battery modules 100 and move in the direction indicated by an arrow.

(27) As described above, therefore, the battery pack according to the present invention is configured to have a structure in which the number of the battery modules can be variously changed based on the size of the battery pack so that the battery modules can be arranged in a matrix pattern, and the battery modules are connected in pairs along each of the arrangements to form flow channels or rows of the battery modules are separately configured to easily form flow channels.

(28) Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

INDUSTRIAL APPLICABILITY

(29) As is apparent from the above description, the battery pack according to the present invention is configured to have a plate-shaped structure in which the width of the battery pack is greater than the height of the battery pack, and therefore, it is possible to install the battery pack in the lower part of a vehicle. As a result, the interior space of the vehicle is increased, and therefore, convenience is improved upon installing the battery pack in the vehicle.

(30) Also, the coolant flow channel between the coolant introduction part and the coolant discharge part is configured to have a structure in which a coolant, introduced through the coolant introduction part, cools the battery modules while passing through the specific battery modules in the vertical direction (the Y direction) on the plane and is discharged through the coolant discharge part. Consequently, it is possible to uniformly distribute the coolant flowing in the flow channels defined between the battery cells, thereby effectively removing heat accumulating between the battery cells and greatly improving the performance and life span of the battery cells.