WO2019174088A1

WO2019174088A1 - Battery module

Info

Publication number: WO2019174088A1
Application number: PCT/CN2018/082252
Authority: WO
Inventors: 秦峰; 王志; 马林; 肖信福; 王晓帆
Original assignee: 宁德时代新能源科技股份有限公司
Priority date: 2018-03-16
Filing date: 2018-04-09
Publication date: 2019-09-19
Also published as: CN207896194U

Abstract

A battery module, comprising: a case (10), comprising a housing (11) provided with an opening and a cover (13) provided for closing the opening; a cell group (20) provided in the housing (11), the cell group (20) comprising multiple cells (21) disposed in layers and an electrical connection member (22) for electrically connecting the multiple cells (21); module output electrodes (30) provided on the cover (13); and fuses (40) provided between the cover (13) and the cell group (20), the module output electrodes (30) being connected to the electrical connection member (22) by means of the fuses (40). According to the battery module provided by the present invention, fire and explosion of cells caused by short circuit, overcharge and other problems can be avoided; moreover, the fuses are disposed outside the cells of the cell group, and would not affect the electrolyte inside the cells when fusing, thereby further ensuring the safety of the battery module.

Description

Battery module

Technical field

The utility model relates to the technical field of batteries, in particular to a battery module.

Background technique

With the wide application of new energy vehicles, the safety of single cells has also received more and more attention. For battery modules formed by grouping of single cells, single cells are prone to short circuit and overcharge. If no measures are taken, the single battery may be subject to fire and explosion, which may lead to safety problems such as explosion of the battery module.

In order to solve the problem of short circuit or overcharge of the single cell causing fire or explosion of the battery or the battery module, a fuse is usually disposed inside the single battery, and the fuse is blown when the single battery is short-circuited or overcharged, thereby Cut off the circuit. Although this technology can solve the problems of short circuit and overcharge of single battery, it still has safety hazard, that is, when the fuse is placed inside the battery core, the fuse will be in the electrolyte vapor environment inside the single battery. When the fuse is blown, the electrolyte may be ignited and the single cell may ignite and explode, thereby causing the entire battery module to explode. Therefore, the battery module of the prior art still has an explosion hazard.

Utility model content

The embodiment of the present invention provides a battery module, which can effectively prevent fire and explosion of the single battery, thereby effectively avoiding safety problems such as explosion of the battery module.

In one aspect, a battery module is provided according to an embodiment of the present invention, comprising: a box body including an outer casing having an opening and a cover plate provided with a closed opening; a single battery pack disposed in the outer casing, the single battery pack including a plurality of single cells stacked in a stack and electrical connectors electrically connecting the plurality of single cells; a module output pole disposed on the cover plate; and a fuse disposed between the cover plate and the single battery pack, wherein the module The output pole and the electrical connector are electrically connected by a fuse.

According to an aspect of an embodiment of the present invention, a fuse includes a first connection portion electrically connected to a module output pole, a second connection portion electrically connected to the electrical connector, and between the first connection portion and the second connection portion In the fuse portion, the flow cross section of the fuse portion is smaller than the flow cross section of the first connection portion and the second connection portion, and the fuse portion has a gap with the unit battery unit.

According to an aspect of an embodiment of the present invention, the value of the gap is from 1 mm to 20 mm.

According to an aspect of an embodiment of the present invention, the value of the gap is from 3 mm to 8 mm.

According to an aspect of an embodiment of the present invention, the value of the gap is 5 mm.

According to an aspect of the embodiments of the present invention, the first connecting portion, the second connecting portion and the fuse portion are both plate-shaped structures, and the first connecting portion and the second connecting portion have an angle between the angles of 90°-180 °.

According to an aspect of the embodiments of the present invention, further comprising a conductive electrode post and an "L" shaped adapter, the first connecting portion is electrically connected to the module output through the conductive electrode column, and the second connecting portion is electrically connected through the adapter The connectors are electrically connected.

According to an aspect of the embodiment of the present invention, the fuse portion is in the same plane as the first connection portion, or the fuse portion and the second connection portion are in the same plane.

According to an aspect of the embodiment of the present invention, the fuse portion is formed by extending from one end of the first connecting portion adjacent to the second connecting portion, or the fuse portion is formed by extending from one end of the second connecting portion adjacent to the first connecting portion; There is a gap.

According to an aspect of an embodiment of the present invention, the notch is a rectangular groove.

A battery module according to an embodiment of the present invention includes a box body, a single battery pack, a module output pole, and a fuse. The single battery pack is disposed in the outer casing of the cabinet, and the output pole of the module is disposed in the cabinet. The fuse is located between the cover and the unit battery and is electrically connected to the electrical connector and the module output. When the short circuit or overcharge problem of the single cell causes the instantaneous current of the charging and discharging circuit of the battery module to be too large, the fuse is blown to prevent the single battery from igniting and exploding due to short circuit or overcharge. At the same time, since the fuse is disposed outside the individual cells of the single battery pack, it does not affect the electrolyte inside the single cell and ignites the electrolyte during the fusing, thereby further ensuring the safety of the battery module.

DRAWINGS

Features, advantages, and technical effects of the exemplary embodiments of the present invention will be described below with reference to the drawings.

1 is an exploded perspective view of a battery module according to an embodiment of the present invention;

2 is a schematic structural view of a fuse according to an embodiment of the present invention;

3 is a perspective view of a partial structure of a battery module according to an embodiment of the present invention;

Figure 4 is a front elevational view of the structure shown in Figure 3;

Figure 5 is a cross-sectional view taken along line A-A of Figure 4;

6 is a schematic structural view of a fuse according to another embodiment of the present invention;

Fig. 7 is a schematic structural view of a fuse according to still another embodiment of the present invention.

among them:

10-case; 11-shell; 12-open; 13-cover;

20-cell battery pack; 21-cell battery; 22-electrical connector;

30-module output pole;

40-fuse; 41-first connection portion; 42-second connection portion; 43-fuse portion; 44-notch;

50-conductive electrode column;

60-adapter;

A-angle; b-overcurrent direction.

In the drawings, the same components are denoted by the same reference numerals. The drawings are not drawn to scale.

detailed description

Features and exemplary embodiments of various aspects of the invention are described in detail below. In the following detailed description, numerous specific details are set forth It will be apparent to those skilled in the art, however, that the invention may be practiced without some of these details. The following description of the embodiments is merely provided to provide a better understanding of the invention. In the figures and the following description, at least some of the known structures and techniques are not shown in order to avoid unnecessary obscuring of the present invention; and, for clarity, the dimensions of some of the structures may be exaggerated. Furthermore, the features, structures, or characteristics described hereinafter may be combined in any suitable manner in one or more embodiments.

The orientation words appearing in the following description are all directions shown in the drawings, and are not intended to limit the specific structure of the battery module of the present invention. In the description of the present invention, it should be noted that the terms "installation" and "connection" are to be understood broadly, and may be a fixed connection or a detachable connection, unless otherwise explicitly stated and defined. Or connected in one piece; they can be connected directly or indirectly. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood as the case may be.

In order to better understand the present invention, a battery module according to an embodiment of the present invention will be described in detail below with reference to FIGS. 1 through 7.

Please refer to FIG. 1. FIG. 1 is an exploded perspective view of a battery module according to an embodiment of the present invention. The embodiment of the present invention provides a battery module including a cabinet 10, a single battery pack 20, a module output pole 30, and a fuse 40. The case 10 includes a housing 11 having an opening 12 and a cover 13 provided with a closed opening 12. The unit battery pack 20 is disposed in the outer casing 11, and the unit battery pack 20 includes a plurality of unit cells 21 stacked in a stack and an electrical connector 22 electrically connecting the plurality of unit cells 21. The module output pole 30 is disposed on the cover plate 13 , the fuse 40 is disposed between the cover plate 13 and the unit battery pack 20 , and the module output pole 30 and the electrical connector 22 are electrically connected by the fuse 40 .

In the battery module provided by the embodiment of the present invention, when the short circuit or overcharge problem of the single cell 21 causes the instantaneous current of the charging and discharging circuit of the battery module to be excessively large, the fuse 40 is blown, and the single cell 21 can be prevented from being short-circuited. Fire and explosion occurred in problems such as overcharging. At the same time, since the fuse 40 is disposed outside the respective cells 21 of the unit battery pack 20, it does not affect the electrolyte inside the unit cell 21 and ignites the electrolyte during the fuse, thereby further ensuring the battery module. Security.

Specifically, in the embodiment, the outer casing 11 and the cover 13 of the casing 10 can be made of aluminum alloy, the outer casing 11 is a rectangular frame structure, the opening 12 is located at the upper end surface of the outer casing 11, and the cover plate 13 is plate-shaped. The structure can be sealingly connected to the outer casing 11 by welding or the like to close the opening 12. The module output pole 30 includes a positive output pole and a negative output pole. The positive output pole and the negative output pole are preferably disposed on the surface of the cover plate 13 away from the battery module and connected to the electrical connector 22 through a fuse 40, respectively.

The number of the single cells 21 included in the unit battery pack 20 can be set as required. The plurality of unit cells 21 of the present embodiment are stacked along the length direction of the outer casing 11, and the electrical connector 22 can be specifically connected by aluminum. A sheet, a copper connecting piece or a copper-aluminum composite connecting piece, and a plurality of unit cells 21 are connected in series or in parallel through the electrical connection 22.

Please refer to FIG. 2 together. FIG. 2 is a schematic structural view of a fuse 40 according to an embodiment of the present invention. The fuse 40 of the embodiment of the present invention preferably includes a first connecting portion 41, a second connecting portion 42 and a fuse portion 43 between the first connecting portion 41 and the second connecting portion 42, the first connecting portion 41 and the module The output pole 30 is electrically connected, and the second connecting portion 42 is electrically connected to the electrical connector 22. The battery module provided by the embodiment of the present invention can realize the electrical connection between the single battery pack 20 and the module output pole 30 through the fuse 40, and constitute a charging and discharging circuit, thereby satisfying the charging and discharging requirements of the battery module.

As an alternative embodiment, the over-current section of the fuse portion 43 is smaller than the over-current section of the first connecting portion 41 and the second connecting portion 42 , and at the same time, there is a gap between the fuse portion 43 and the unit battery pack 20 , or Said that there is a distance between the intervals. When the instantaneous current of the battery module charging and discharging circuit is excessive due to a short circuit or overcharge problem of the unit cell 21, the fuse portion 43 of the fuse 40 is previously blown. Since the fuse portion 43 is spaced apart from the unit battery pack 20, the process of forming the molten portion 43 from the molten metal to the liquid metal dropping onto the unit cell 21 is cooled for a period of time, so that the liquid metal is dropped to When the single cell 21 is cooled, the liquid metal falling from the high temperature is directly dropped on the single cell 21, causing some single cells 21 and even the battery module to ignite or explode. The overcurrent section refers to the cross section of the portions of the fuse 40 in the overcurrent direction b in Fig. 2.

The distance between the fuse portion 43 and the unit battery pack 20 can be set according to the model of the battery module, taking into consideration the cooling temperature requirement of the liquid metal and the energy density requirement of the battery module itself, as an optional embodiment. The value of the gap between the fuse portion 43 and the unit battery unit 20 is preferably any value between 1 mm and 20 mm, and includes both end values of 1 mm and 20 mm. Based on the above considerations, the separation distance is further preferably any value between 3 mm and 8 mm, more preferably 5 mm, that is, the cooling temperature requirement of the liquid metal can be better satisfied, and the energy density of the battery module is less affected.

Please refer to FIG. 3 to FIG. 5 together. FIG. 3 is a perspective view showing a partial structure of a battery module according to an embodiment of the present invention, and FIG. 4 is a front view showing the structure shown in FIG. Figure 4 is a cross-sectional view along the AA direction. In order to facilitate electrical connection with the electrical connector 22 and the module output pole 30, as an alternative embodiment, the first connecting portion 41, the second connecting portion 42 and the fuse portion 43 are all plate-shaped structures, A connecting portion 41 and the second connecting portion 42 have an angle a, and the angle a is an arbitrary angle value between 90° and 180°, and includes two end values of 90° and 180°. Since the cover plate 13 has a plate-like structure, the electrical connection member 22 is also a plate-like structure, and the two are spaced apart from each other in the same direction, in order to ensure that the module output pole 30 located on the cover plate 13 through the fuse 40 and located in the single The electrical connectors 22 on the body battery pack 20 are electrically connected, preferably requiring the fuse 40 to be secured. Therefore, as an optional implementation manner, the battery module further includes a conductive electrode post 50 and an "L" shaped adapter 60. The first connecting portion 41 is electrically connected to the module output pole 30 through the conductive electrode post 50. The two connecting portions 42 are electrically connected to the electrical connector 22 through the adapter 60. The first connecting portion 41, the second connecting portion 42, and the fuse portion 43 are all defined as a plate-like structure, and an angle a is disposed between the first connecting portion 41 and the second connecting portion 42, and the angle a is defined as Any angle value between 90 ° and 180 °, so that the first connecting portion 41 can be closely attached to the end of the conductive electrode column 50 facing the single battery pack 20 and fixed by welding, bonding, etc., so that the first connecting portion 41 can The structure of the conductive column 50 and the like is electrically connected to the module output pole 30 on the surface of the cover plate 13 away from the single battery pack 20, and the second connecting portion 42 can pass through the "L"-shaped adapter 60 and the electrical connector 22. The electrical connection ensures the strength of the connection with the electrical connector 22.

As an alternative embodiment, the fuse portion 43 and the first connecting portion 41 are in the same plane, so that the fuse portion 43 is not easily bent when the battery unit 21 is expanded and deformed or the battery module is shaken. The breakage ensures the life of the fuse 40, and the fuse 40 is prevented from being broken due to the short circuit or overcharge of the non-single battery 21, thereby ensuring the service life of the battery module.

Of course, the fuse 40 is not limited to be in the same surface as the first connecting portion 41. In some alternative embodiments, when the fuse portion 43 of the fuse 40 is strong enough, it can overcome the expansion deformation of the unit cell 21 or the appearance of the battery module. When the sway is caused to break, the fuse portion 43 may be flush with the second connecting portion 42.

As an alternative embodiment, in order to facilitate the production of the fuse 40, the processing cost of the fuse 40 is reduced, and the fuse portion 43 is formed by extending one end of the first connecting portion 41 near the second connecting portion 42, that is, at least the first connection. The portion 41 and the fuse portion 43 are of a unitary structure. As described above, since the flow cross section of the fuse portion 43 is required to be smaller than the flow cross section of the first connection portion 41 and the second connection portion 42, the other portions of the fuse 40 are preceded by the fuse 40. The part is pre-blown. Therefore, in the present embodiment, the notch 44 is provided in the fuse portion 43 to satisfy the requirement that the flow cross section is small. The number of the notches 44 may be one as shown in FIG. 2. One notch 44 is preferably located at a central position in the width direction of the fuse portion 43 or a position close to the center, and the notch 44 is a closed notch 44 formed by enclosing four faces. The shape of the notch 44 is preferably a rectangular groove.

Of course, the fuse 40 shown in FIG. 2 is only a preferred embodiment, and is not limited to the above form. Please refer to FIG. 6 and FIG. 7 together. FIG. 6 shows a fuse of another embodiment of the present invention. FIG. 7 is a schematic structural view of a fuse 40 according to still another embodiment of the present invention. As shown in FIG. 6, the notches 44 on the fuse portion 43 may also be disposed in two. The two notches 44 may be spaced apart in the extending direction of the fuse portion 43, and the notches 44 of the two fuses 40 are all four. The face is surrounded by a closed notch, and the shape of the notch 44 is preferably a rectangular groove. Of course, the notch 44 is not limited to the closed rectangular notch. As shown in FIG. 7, the number of the notches 44 is also two. The two notches 44 are oppositely disposed in the width direction of the fuse portion 43, and each notch 44 is three. The side on which the face is formed has a rectangular notch with an opening 12. Of course, the number and arrangement of the notches 44 can be set according to the needs of use, as long as the requirements of the flow cross section of the fuse portion 43 can be satisfied.

It can be understood that the above embodiments are formed by extending the fuse portion 43 from the first connecting portion 41 to the end of the second connecting portion 42. Of course, in some optional embodiments, the fuse portion 43 may also be The two connecting portions 42 are formed adjacent to one end of the first connecting portion 41, that is, at least the second connecting portion 42 and the fuse portion 43 are integrally formed, and the notch 44 is disposed on the fuse portion 43, the number and shape of the notches 44 The requirements are the same as those provided on the first connecting portion 41, and will not be described herein.

In practice, the first connecting portion 41, the fuse portion 43, and the second connecting portion 42 may be of a unitary structure for easier processing, that is, the fuse 40 is preferably an integrally formed member.

Therefore, the battery module provided by the embodiment of the present invention includes the casing 10, the single battery pack 20, the module output pole 30 and the fuse 40, and the unit battery pack 20 is disposed on the outer casing 11 of the casing 10. The module output pole 30 is disposed on the cover 13 of the casing 10, and the fuse 40 is located between the cover 13 and the unit battery pack 20 and electrically connected to the electrical connector 22 and the module output pole 30. Therefore, when the short circuit or overcharge problem of the single cell 21 causes the instantaneous current of the charging and discharging circuit of the battery module to be excessive, the fuse 40 is blown to prevent the single cell 21 from being ignited and exploded due to problems such as short circuit or overcharge. At the same time, since the fuse 40 is disposed outside the respective cells 21 of the unit battery pack 20, it does not affect the electrolyte inside the unit cell 21 and ignites the electrolyte during the fuse, thereby further ensuring the battery module. Safe and easy to promote.

Although the present invention has been described with reference to the preferred embodiments thereof, various modifications may be made thereto and the components may be replaced with equivalents without departing from the scope of the invention. In particular, the technical features mentioned in the various embodiments can be combined in any manner as long as there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

A battery module, comprising:

a case comprising an outer casing having an opening and a cover plate enclosing the opening;

a single battery pack disposed in the outer casing, the single battery pack including a plurality of unit cells disposed in a stack and electrical connectors electrically connecting the plurality of unit cells;

a module output pole disposed on the cover plate;

a fuse disposed between the cover plate and the single battery pack;

The module output pole and the electrical connector are electrically connected through the fuse.
The battery module according to claim 1, wherein said fuse comprises a first connecting portion electrically connected to said module output, a second connecting portion electrically connected to said electrical connecting member, and a fuse portion between the first connection portion and the second connection portion, wherein a cross section of the fuse portion is smaller than a flow cross section of the first connection portion and the second connection portion, the fuse portion There is a gap with the unit battery pack.
The battery module according to claim 2, wherein the gap has a value of 1 mm to 20 mm.
The battery module according to claim 3, wherein the value of the gap is 3 mm to 8 mm.
The battery module according to claim 4, wherein the gap has a value of 5 mm.
The battery module according to any one of claims 2 to 5, wherein the first connecting portion, the second connecting portion, and the fuse portion are both plate-like structures, and the first connecting portion There is an angle with the second connecting portion, and the angle is between 90° and 180°.
The battery module according to claim 6, further comprising a conductive electrode post and an "L" shaped adapter, wherein the first connecting portion is electrically connected to the module output through the conductive electrode post The second connecting portion is electrically connected to the electrical connector through the adapter.
The battery module according to claim 6, wherein the fuse portion is in the same plane as the first connecting portion, or the fuse portion and the second connecting portion are in the same plane.
The battery module according to claim 6, wherein the fuse portion is formed by one end of the first connecting portion close to the second connecting portion, or the fuse portion is connected by the second connection The portion is formed to extend toward one end of the first connecting portion; the fuse portion is provided with a notch.
The battery module according to claim 9, wherein the notch is a rectangular groove.