WO2015127839A1 - Battery module - Google Patents

Abstract

The present invention relates to a battery module comprising a battery pack, a first base plate, a second base plate, a column and an elastic element, wherein the battery pack comprises a plurality of individual battery cells mutually stacked; the battery pack, the column and the elastic element are all arranged between the first base plate and the second base plate; the elastic element is arranged between the battery pack and the first base plate and applies pressure to the plurality of the individual battery cells in the stacking direction of the plurality of the individual battery cells; and both ends of the column are fixedly connected with the first base plate and the second base plate respectively, and limit the plurality of the individual battery cells in the direction perpendicular to the stacking direction.

Description

Battery module Technical field

The present invention relates to a battery module, and more particularly to a battery module having a package structure.

Background technique

Lithium battery is a new type of energy storage battery, which has the advantages of high energy density and long life, but it also has the disadvantages of high technical difficulty and high risk. A single lithium battery unit has limited energy storage. For a high-power power supply requiring a lithium battery, a lithium battery unit must be used to form a lithium battery module to achieve high energy storage and high power requirements, which requires a well-designed mechanism. These lithium battery cells are packaged. The key technology of the lithium battery module is not only the production technology of the single battery and the management and control technology of the battery module, but also the packaging technology of the battery module, and the three determine the high performance and reliability of the power battery module.

Since the lithium battery generates a large amount of heat during charging and discharging, the volume of the battery unit is easily expanded, thereby destroying the overall robustness of the battery module packaging mechanism. The existing lithium battery modules have different packaging mechanisms depending on the power level. For low-power lithium battery modules, the separator and the outer casing are generally directly packaged, and as the internal battery expands, the non-elastic outer casing may be broken. For high-power lithium battery modules, a rigid packaging mechanism is generally used. In order to cool down and equalize temperature, a ventilation mechanism and a fan or a water-cooling device are installed inside to prevent thermal expansion, resulting in a large volume and complicated mechanism.

Summary of the invention

In view of this, it is indeed necessary to provide a battery module having a package structure that is strong and adapts to thermal expansion.

A battery module includes a battery pack, a first bottom plate, a second bottom plate, a column, and an elastic member, the battery pack includes a plurality of battery cells stacked on each other, and the battery pack, the column and the elastic member are disposed on the first bottom plate The elastic member is disposed between the battery pack and the first bottom plate, and applies pressure to the plurality of battery cells in a stacking direction of the plurality of battery cells, both ends of the column The first bottom plate and the second bottom plate are respectively fixedly connected, and the plurality of battery cells are limited in a direction perpendicular to the superposition direction.

According to the present invention, by placing an elastic member between the battery pack and the first bottom plate, pressure is applied to the battery cells in the stacking direction, so that the battery cells can be fixed during normal use and can be expanded outward during thermal expansion. The original package structure is not damaged, thereby improving the reliability of the package structure. And the battery module is small in size and simple in structure.

DRAWINGS

1 is a schematic view showing the assembly of a battery module according to an embodiment of the present invention.

2 is a blasting diagram of the opening of the bottom plate of the battery module of FIG. 1.

3 is a top plan view of the battery module of FIG. 1 with the bottom plate removed.

4 is a schematic structural view of a battery pack in the battery module of FIG. 1.

FIG. 5 is a partial plan view of the battery pack and the pillar in the battery module of FIG. 1. FIG.

6 is a schematic view showing a wiring structure of the battery module of FIG. 1.

Fig. 7 is a partial enlarged view of the wiring structure of Fig. 6.

Main component symbol description

Battery module	1
First bottom plate	10
Second bottom plate	20
Fixed structure	102
Trench	104
Column	30
Slot structure	302
Elastic component	40
Battery	50
First side	506
edge	504
Second side	502
Battery cell	510
Positive terminal	512
Negative terminal	514
hole	516
Insulation connecting plate	520
Tunnel	522
Screw hole	524
Insulating cover	530
Through hole	532
Electrical lead	540
Screw	550
Thermal sheet	560
heat sink	570
bolt	572
Press plate	60

The invention will be further illustrated by the following detailed description in conjunction with the accompanying drawings.

detailed description

The battery module provided by the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

Referring to FIGS. 1 through 4, the present invention provides a battery module 1 including a first bottom plate 10, a second bottom plate 20, a post 30, an elastic member 40, and a battery pack 50. The battery pack 50, the column 30, and the elastic member 40 are disposed between the first bottom plate 10 and the second bottom plate 20. The battery pack 50 includes a plurality of battery cells 510 stacked one on another. The elastic member 40 is disposed between the battery pack 50 and the first bottom plate 10, and applies pressure to the plurality of battery cells 510 in the stacking direction X of the plurality of battery cells 510. The post 30 may be a rod-shaped rigid structure for supporting, fixing and spacing the first bottom plate 10 and the second bottom plate 20. The two ends of the column 30 are fixedly connected to the first bottom plate 10 and the second bottom plate 20, respectively, and the plurality of battery cells 510 are constrained in a direction perpendicular to the superposition direction X.

The first bottom plate 10 and the second bottom plate 20 may be rigid plate-like structures, and the size may be determined according to the number of the battery packs 50 in the battery module 1. The surface may have a fixing structure 102, such as a fixing hole, for connecting with the column 30. In addition, the surfaces of the first bottom plate 10 and the second bottom plate 20 may also have a plurality of mutually parallel and transparent grooves 104 to facilitate heat dissipation of the battery pack 50 outward.

The battery cell 510 may be in the form of a sheet, a plane, a plate or a layer, and is superposed in the thickness direction. Each battery cell 510 is an electrochemical cell capable of independent charging and discharging, such as a lithium ion battery, a lithium sulfur battery or a nickel hydrogen battery. The plurality of battery cells 510 of the same battery pack 50 are disposed parallel to each other and stacked, and are parallel to the first bottom plate 10 and the second bottom plate 20. A plurality of battery cells 510 of the same battery pack 50 are connected in series to each other.

The number of the elastic members 40 may be plural, and is preferably in a compressed state, thereby providing a pressure against the battery pack 50, the direction of the pressure being the superposition direction X of the plurality of battery cells 510, that is, perpendicular to the first A bottom plate 10, a second bottom plate 20 and a battery cell 510 press the plurality of battery cells 510 against each other to achieve positional fixation in an unexpanded state. However, the elastic member 40 is not at the elastic compression limit, that is, it can be further elastically compressed, so that the plurality of battery cells 510 can further compress the elastic member in the stacking direction X when the volume is expanded. It can be understood that the elastic member 40 can also be in an uncompressed state, that is, the pressure is not sufficient to elastically deform the elastic member 40. In summary, the elastic member 40 only needs to apply pressure to the plurality of battery cells 510 in the stacking direction X, so that the plurality of battery cells 510 are pressed against each other, and the elastic member 40 can still be elastically compressed. The elastic member 40 can be a spring, an elastic column or a spring piece.

The distance between the first bottom plate 10 and the second bottom plate 20 can be adjusted to adjust the amount of pressure applied by the elastic member 40. In an embodiment, the first bottom plate 10 and the column 30 can be connected by bolts, and the distance between the first bottom plate 10 and the second bottom plate 20 can be adjusted by adjusting bolts. In another embodiment, the post 30 can be a rigid rod of adjustable length so that the distance between the first bottom plate 10 and the second bottom plate 20 can be adjusted.

The battery unit 510 closest to the first bottom plate 10 of the battery pack 50 is spaced apart from the first bottom plate 10 by the elastic member 40, and the battery unit 510 closest to the second bottom plate 20 can be directly disposed at the first On the second bottom plate 20. In another embodiment, an elastic member 40 may be disposed between the battery pack 50 and the second bottom plate 20, and the elastic member 40 is disposed on the second bottom plate 20 and the battery unit 510 closest to the second bottom plate 20. between.

The battery module 1 may further include a pressure plate 60 disposed between the battery pack 50 and the elastic member 40, that is, between the battery unit 510 closest to the elastic member 40 and the elastic member 40. The surface of the pressure plate 60 may have elastic member positioning holes for connecting and positioning the elastic member 40. The pressure plate 60 may have the same shape as the battery cell 510, and is superposed on the battery cell 510, and the elastic member 40 applies pressure to the plurality of battery cells 510 through the pressure plate 60. The pressure plate 60 can evenly distribute the pressure applied by the elastic member 40 and act on the battery unit 510.

The stacking direction X perpendicular to the plurality of battery cells 510 may be a plurality of directions belonging to the same plane, and the number of the pillars 30 may be plural, so that the plurality of battery cells 510 are in any direction perpendicular to the stacking direction X. The upper limit position is such that the plurality of battery cells 510 are fixed in position perpendicular to the stacking direction X. The plurality of battery cells 510 of the same battery pack 50 may have exactly the same shape and completely overlap when stacked. The battery pack 50 can have sides and ribs 504 that are parallel to the stacking direction X. The plurality of uprights 30 can respectively abut against a plurality of edges of the battery cell 510, for example, against a side of the battery pack 50. In a preferred embodiment, the plurality of posts 30 respectively secure the corners of the battery cells 510, such as against the corners of the battery cells 510, such as against the ribs 504 of the battery pack 50. Referring to FIG. 5, more preferably, the post 30 has a slot structure 302 corresponding to the corner of the battery cell 510 or the shape of the edge 504 of the battery pack 50 to accommodate the corner of the battery cell 510 or the battery pack 50. The rib 504 is fixed to the battery pack 50 perpendicular to the stacking direction X, for example, the corner of the battery cell 510 or the rib 504 of the battery pack 50 is abutted in the slot structure 302, such as a rectangular battery bill. The right angle of the body 510 abuts against the right angled trough structure 302. Since the position of the uprights 30 relative to the first bottom plate 10 and the second bottom plate 20 is fixed, the battery cells 510 that abut against the uprights 30 are also fixed in position perpendicular to the stacking direction X. It can be understood that the column 30 does not limit the battery cell 510 parallel to the stacking direction X, and the battery cell 510 can still resist the pressure application of the elastic member 40 in the stacking direction X. When the battery module 1 comprises a pressure plate 60, the column 30 also limits the pressure plate 60 in a direction perpendicular to the superposition direction X.

Each of the battery cells 510 may include a positive electrode terminal portion 512 and a negative electrode terminal portion 514 extending outward from the body of the battery cell 510 for interconnection and connection with an external circuit for charging and discharging. The positive terminal portion 512 and the negative electrode terminal portion 514 are disposed on the same side of the battery cell 510 for wiring. Preferably, the positive terminal portion 512 and the negative electrode terminal portion 514 of all the battery cells 510 in the same battery pack 50 are disposed on the same side of the battery pack 50, for example, both disposed on the first side face 506 of the battery pack 50. More preferably, the positive terminal portion 512 and the negative electrode terminal portion 514 of all the battery cells 510 in the same battery pack 50 are equally spaced, so that the positive electrode terminal portion 512 and the negative electrode terminal portion 514 of the different battery cells 510 can be in the stacking direction X. The positions of each other coincide.

In one embodiment, in order to connect the plurality of battery cells 510 of the same battery pack 50 to each other, the positive terminal portion 512 of each battery cell 510 and the negative electrode terminal portion 514 of the adjacent battery cell 510 are in the superposition direction X. The upper positions of the battery cells 510 are overlapped with the positive electrode terminals 512 of the adjacent battery cells 510 in the stacking direction X, so that the positive electrode terminals 512 of the plurality of battery cells and The negative terminal portions 514 are arranged in two rows on the first side 506 of the battery pack 50 to facilitate series connection.

Referring to FIG. 6 and FIG. 7 , the battery pack 50 may further include an insulating connecting plate 520, an insulating cover 530 and a plurality of electrical lead wires 540 as a connecting mechanism between the battery pack 50 and the external circuit. The insulating connecting plate 520, the insulating cover 530 and the plurality of electrical lead wires 540 and the positive electrode connecting portion 512 and the negative electrode connecting portion 514 are both located on the first side surface 506 of the battery pack 50. The insulating connecting plate 520 is disposed between the insulating cover 530 and the plurality of battery cells 510. The positive connecting portion 512 and the negative connecting portion 514 pass through the insulating connecting plate 520, and are partially disposed on the insulating connecting plate 520. Between the insulating cover plates 530. The plurality of electrical lead wires 540 pass through the insulating cover plate 530 for connecting the positive electrode terminal portion 512 and the negative electrode terminal portion 514 of the battery cell 510 to an external circuit.

Preferably, all of the battery cells 510 of the battery pack 50 are located in the same row, and both the positive terminal portion 512 and the negative electrode terminal portion 514 pass through the same insulating connecting plate 520. The battery pack 50 can include two sets of connection mechanisms that are respectively connected to the two rows of positive electrode connection portions 512 and negative electrode connection portions 514.

The insulating connecting plate 520 includes a plurality of holes 522 corresponding to the positive electrode connecting portion 512 and the negative electrode connecting portion 514, and the positive electrode connecting portion 512 and the negative electrode connecting portion 514 can pass through. The portions of the positive electrode connecting portion 512 and the negative electrode connecting portion 514 passing through the corresponding holes 522 are superposed on each other on the insulating connecting plate 520 to form an electrical connection. The shape of the hole 522 may correspond to the shape of the positive electrode connecting portion 512 and the negative electrode connecting portion 514. For example, the positive electrode connecting portion 512 and the negative electrode connecting portion 514 have a strip shape, and the shape of the opening 522 is a groove shape. The shape of the positive electrode connecting portion 512 and the negative electrode connecting portion 514 is linear, and the shape of the opening 522 is also a hole shape.

In this embodiment, the positive electrode connecting portion 512 and the negative electrode connecting portion 514 are superposed on each other before passing through the hole 522, and the stacked positive electrode connecting portion 512 and the negative electrode connecting portion 514 pass through the same hole 522 at the same time. The number of the holes 522 of the insulating connecting plate 520 is equal to the number of the positive connecting portion 512 or the negative connecting portion 514, and the position of the opening 522 corresponds to the positions of the stacked positive connecting portion 512 and the negative connecting portion 514. .

In another embodiment, the positive terminal 512 and the negative terminal 514 are superposed on each other after passing through the hole 522, that is, the positive terminal 512 and the negative terminal 514 respectively pass through different holes 522. The number of the holes 522 of the insulating connecting plate 520 is equal to the sum of the number of the positive electrode connecting portion 512 and the negative electrode connecting portion 514, and the position of the hole 522 corresponds to the positions of the positive electrode connecting portion 512 and the negative electrode connecting portion 514.

The insulating cover 530 has a U-shaped groove matching the shape of the insulating connecting plate 520, so that the insulating cover 530 can be fastened outside the insulating connecting plate 520. After the insulating connecting plate 520 is disposed on the first side surface 506 and the positive electrode connecting portion 512 and the negative electrode connecting portion 514 are passed through the corresponding holes 522 and overlapped with each other on the insulating connecting plate 520, the insulating cover plate 530 is disposed. The outer side of the insulating connecting plate 520 is fastened, so that the positive electrode connecting portion 512 and the negative electrode connecting portion 514 are compacted with each other to achieve stable electrical contact. The insulating cover 530 may have a through hole 532 exposing a portion where the positive electrode connecting portion 512 and the negative electrode connecting portion 514 overlap, for allowing the electric lead wire 540 to pass through the through hole 532 and the positive electrode connecting portion 512 and The negative terminal portion 514 achieves electrical contact. In order to measure the voltage and current of each battery cell 510, a through hole 532 may be disposed on the insulating cover 530 corresponding to a position where each positive electrode terminal 512 and the negative electrode terminal 514 are overlapped, and the plurality of electrical lead wires 540 are respectively The positive electrode wiring portion 512 and the negative electrode wiring portion 514 are electrically connected to each other through the plurality of through holes 532.

To secure the electrical lead 540, the battery pack 50 can further include a screw 550. The screw 550 itself can be electrically conductive and connected to the end of the electrical lead 540. The insulating connecting plate 520 is provided with a screw hole 524 corresponding to a portion where the positive electrode connecting portion 512 and the negative electrode connecting portion 514 are overlapped, and the positive electrode connecting portion 512 and the negative electrode connecting portion 514 also have a hole 516 corresponding to the position at the overlapping portion, thereby The screw 550 can pass through the through hole 532 of the insulating cover 530 and the hole 516 of the positive terminal 512 and the negative terminal 514 and screwed onto the screw hole 524 of the insulating connecting plate 520.

It can be understood that the size of the through hole 532 can be larger than the size of the electric lead wire 540 and the screw 550 in order to meet the displacement requirement of the thermal expansion of the battery.

Through the arrangement of the insulating connecting plate 520, the insulating cover 530 and the electric lead wire 540, the connection of the circuit can be made simpler and more reliable, and the detachment due to vibration can be avoided.

Since electrochemical cells, especially lithium-ion batteries, generate a large amount of heat during charging and discharging, if they are not conducted in time, the performance of the battery may be degraded, and a serious explosion may occur. To facilitate heat conduction of the battery cell 510 and heat dissipation of the battery pack 50, the battery pack 50 may further include a heat conductive sheet 560 and a heat sink 570. The battery pack 50 can have a second side 502 that is perpendicular to the stacking direction X and that is different from the first side 506. The heat conductive sheet 560 is disposed between the stacked battery cells 510, and the heat dissipation capability of the battery cells 510 can be improved. The heat conducting sheet 560 protrudes from a side of the adjacent battery cell 510 toward the heat sink 570 and is bent, and the bent portion is in contact with the heat sink 570. The heat sink 570 is located on the second side 502 of the battery pack 50.

The heat conducting sheet 560 may be plural and disposed between each two adjacent battery cells 510. The heat conductive sheet 560 has a sheet structure and may be a metal sheet. The heat conducting sheet 560 protrudes from the adjacent battery cells 510 toward the second side surface 502 having the heat sink 570 and is bent to be attached to the side of the battery cell 510.

The heat sink 570 can cover the entire second side surface 502, the outer side has a heat dissipation fin to increase the heat dissipation area, and the inward side has a flat surface disposed on the side of the plurality of battery cells 510. And contacting the bent portion of the heat conducting sheet 560, the heat of the battery unit 510 is conducted to the heat sink 570 through the heat conducting sheet 560 and diffused outward to achieve heat dissipation. The heat sink 570 can be fixed to the column 30 by bolts 572. The bolts 572 can also press the heat sink 570 and the portion of the heat conductive sheet 560 to reduce the thermal resistance.

In one embodiment, the battery module 1 includes a plurality of battery packs 50 each having at least one heat sink 570 located outside the entire battery module 1 to allow the battery pack 50 to dissipate heat outward rapidly. Specifically, each of the battery packs 50 has at least one second side 502 located outside the entire battery module 1. To facilitate internal heat dissipation, the plurality of battery packs 50 may be spaced apart from one another.

Further, the operating temperature range of the battery is -20 ° C to 60 ° C. If there is a temperature difference between the plurality of battery packs 50 during operation, the performance may be uneven, thereby affecting the power supply, and thus the different battery cells 510 and different The temperature difference between the battery packs 50 should be as small as possible. The battery module 1 may further include a heat pipe disposed in the middle of the battery module 1 and passing through the heat conducting sheet 560, and the plurality of battery packs 50 are connected to the same heat pipe to improve the heat dissipation and the heat equalizing capacity of the battery pack 50, thereby reducing the temperature difference. .

In order to reduce the total weight of the battery module 1 and increase the energy density of the battery module 1, the first bottom plate 10, the second bottom plate 20, the column 30, the elastic member 40, the pressing plate 60, the heat pipe, the heat conducting sheet 560 and the heat sink 570 may be Use lightweight and high strength materials such as lightweight aluminum alloys, magnesium alloys or magnesium alloys.

In addition, those skilled in the art can make other changes in the spirit of the present invention. Of course, the changes made in accordance with the spirit of the present invention should be included in the scope of the present invention.

Claims (13)

1. A battery module includes a battery pack including a plurality of battery cells stacked on each other, wherein the battery module further includes a first bottom plate, a second bottom plate, a pillar, and an elastic member, the battery pack and the pillar The elastic elements are disposed between the first bottom plate and the second bottom plate, the elastic element is disposed between the battery pack and the first bottom plate, and the plurality of battery cells are stacked in a direction of the plurality of battery cells Pressure is applied thereto, and two ends of the column are fixedly connected to the first bottom plate and the second bottom plate respectively, and the plurality of battery cells are limited in a direction perpendicular to the stacking direction.
2. The battery module according to claim 1, wherein the elastic member is still elastically compressible while applying the pressure.
3. The battery module according to claim 1, wherein the battery module further comprises a pressure plate disposed between the battery pack and the elastic member.
4. The battery module according to claim 1, wherein the battery pack has an edge parallel to the superimposing direction, and the post has a groove structure corresponding to the rib shape of the battery pack to accommodate the rib of the battery pack. Thereby the battery pack is fixed from perpendicular to the superposition direction.
5. The battery module according to claim 1, wherein the plurality of battery cells of the same battery pack are connected in series, each of the battery cells including a positive electrode terminal portion and a negative electrode terminal portion extending outward from the body of the battery cell The positive terminal portion of each battery cell and the negative electrode terminal portion of the adjacent battery cell overlap in the stacking direction, and the negative electrode terminal portion of each battery cell overlaps with the positive electrode terminal portion of the adjacent battery cell The positions in the direction coincide.
6. The battery module according to claim 5, wherein the battery pack further comprises an insulating connecting plate, an insulating cover plate and an electrical lead wire, the insulating connecting plate being disposed between the insulating cover plate and the plurality of battery cells The positive terminal portion and the negative terminal portion pass through the insulating connecting plate, and are partially disposed between the insulating connecting plate and the insulating cover plate, and the electrical lead wire passes through the insulating cover plate and the positive terminal portion of the battery cell and The negative terminal is connected.
7. The battery module according to claim 1, further comprising a heat conducting sheet and a heat sink, the heat sink being disposed on a side of the battery pack, the heat conducting sheet being superposed between the stacked battery cells, and Extending and bending from an adjacent battery cell toward a side of the heat sink, the heat sink is fixed on the pillar and is in contact with the bent portion of the heat conductive sheet.
8. The battery module according to claim 1, wherein the battery module comprises a plurality of battery packs each having at least one heat sink located outside the entire battery module.
9. The battery module according to claim 8, wherein the battery module comprises a heat pipe, and the heat pipes are respectively connected to the plurality of battery packs.
10. The battery module according to claim 1, wherein at least one of the first bottom plate and the second bottom plate has a plurality of mutually parallel and transparent grooves.
11. The battery module according to claim 1, wherein the battery cells are in the form of a sheet, a surface, a plate or a layer, and the plurality of battery cells of the same battery pack are parallel and superposed on each other, and are parallel to The first bottom plate and the second bottom plate.
12. The battery module according to claim 1, wherein a distance between the first bottom plate and the second bottom plate is adjustable such that a magnitude of the pressure applied by the elastic member is adjustable.
13. The battery module according to claim 1, wherein the first bottom plate, the second bottom plate, the column, the elastic member, the pressure plate, the heat pipe, the heat conductive sheet and the heat sink are made of an aluminum alloy, a magnesium alloy or a magnesium alloy.

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