KR100696670B1 - Secondary battery module - Google Patents

Abstract

The secondary battery module according to the present invention is fastened to a plurality of unit cells including an electrode terminal protruding outward and a connecting member electrically connecting the unit cells and the electrode terminal so as to reduce contact resistance between electrode terminals. And a nut supporting the connecting member, and a washer interposed between the nut and the connecting member and having protrusions formed on at least one surface thereof.

Secondary battery module, connecting member, washer, protrusion

Description

Secondary Battery Module {SECONDARY BATTERY MODULE}

1 is an exploded perspective view illustrating a rechargeable battery module according to a first exemplary embodiment of the present invention.

2 is a partial cross-sectional view showing a unit cell according to a first embodiment of the present invention.

3 is a cutaway perspective view showing a washer according to a first embodiment of the present invention.

4 is a partial cross-sectional view showing a unit cell according to a second embodiment of the present invention.

5 is a perspective view showing a washer according to a third embodiment of the present invention.

The present invention relates to a secondary battery module, and more particularly, to a secondary battery module having an improved structure for electrically connecting electrode terminals of neighboring unit cells.

A secondary battery is a battery that can be charged and discharged unlike a primary battery that is not rechargeable. Low-capacity secondary batteries are used in portable electronic devices such as mobile phones, notebook computers, and camcorders, and large-capacity batteries are widely used as power sources for driving motors in hybrid vehicles.

Recently, a high output secondary battery using a high energy density nonaqueous electrolyte has been developed, and the high output secondary battery connects a plurality of batteries in series so as to be used for driving a motor such as an electric vehicle requiring a large power. It consists of a large capacity secondary battery.

In addition, one large-capacity secondary battery (hereinafter referred to as a battery module for convenience of description throughout) is composed of a plurality of secondary batteries (hereinafter referred to as unit cells for convenience of explanation throughout) in series.

Each of the unit cells has a case having an electrode group in which a positive electrode and a negative electrode are positioned with a separator interposed therebetween, and a case having a space in which the electrode group is built, and a cap having a through hole in which the case is sealed and an electrode terminal is inserted. A plate, an electrode terminal electrically connected to the electrode group and inserted into the through hole and including an anode terminal and a cathode terminal protruding out of the case, and a gasket inserted into the through hole to insulate the cap plate from the electrode terminal. do.

Here, the case is manufactured in various shapes, and typical shapes include cylindrical and rectangular shapes. And the rectangular battery is composed of a case of a hexahedral shape with one side opened, a cap plate blocking the opening and an electrode terminal provided on the cap plate. In addition, the positive electrode terminal and the negative electrode terminal are made of male threads, and nuts are fastened to the respective electrode terminals to fix the electrode terminals on the cap assembly.

Each of the unit cells is arranged so that the positive electrode terminal and the negative electrode terminal are crossed with the positive terminal and the negative terminal of the neighboring unit cell so as to be connected in series. In addition, the connecting member is fitted to the positive terminal of the unit cell and the negative terminal of the neighboring unit cell, and the nut is fastened again on the connecting member so that the connector is stably fixed to the electrode terminal.

In addition, a washer is installed between the connecting member and the nut to improve the fastening force of the nut.

The electrode terminals of neighboring unit cells are electrically connected to neighboring unit cells through nuts, washers, and connectors. However, this structure has a problem in that the contact resistance is generated by non-uniform contact between the two members in contact with the washer and connector. Although the surface is smoothly machined in appearance, microscopically there is a rugged portion on the surface, which causes both members to be in point contact. As such, when the washer and the connection member make point contact, the contact area is small to increase the contact resistance, and there is a problem in that the output of the secondary battery module is reduced due to such resistance.

In particular, when the battery module is mounted on the device and used for a long time, the nut is loosened due to external vibration, and the contact resistance at the contact surface is further increased.

In addition, there is a problem that the contact resistance occurs as described above also in the contact with the nut and the washer.

In particular, in the case of a secondary battery module for a HEV (hybrid electric vehicle), the vibration of the battery module is continuously applied to the battery module as the vehicle travels, so that the nut is released, thereby increasing the contact resistance between the unit cells. In addition, in the HEV secondary battery module, since several tens of unit cells are connected in series, when a contact resistance occurs in a portion connecting the unit cells, there is a problem in that the output of the battery module is significantly reduced.

Accordingly, the present invention has been made to solve the above problems, an object of the present invention is to provide a secondary battery module that can reduce the contact resistance by improving the structure of the washer installed in the electrode terminal.

In order to achieve the above object, the battery module according to the present invention includes a washer having protrusions formed on at least one surface thereof.

The battery module according to the present invention includes a plurality of unit cells including an electrode terminal protruding outward, a connector coupled to the electrode terminal to electrically connect the unit cells, and the connector connected to the electrode terminal. It may include a supporting nut, and a washer interposed between the nut and the connector and a protrusion formed on at least one surface.

The protrusion may be formed on one surface of the washer in contact with the connector, or may be formed on both sides of the washer.

 The protrusion may have a sharp end in the form of a wedge, and the protrusion may be continuously formed along the circumferential direction of the washer.

In addition, the protrusion may be formed in the shape of a horn.

And the connector may be made in the form of a plate.

The protrusion may be pressed by the nut to be in close contact with the connecting member, and the protrusion may be further pressed by the nut to be installed to penetrate the surface of the connecting member.

In addition, the protrusion may be formed on both sides of the washer and pressed by the nut to be in close contact with the surface of the connecting member and the nut, it may be installed in a structure that is further pressed by the nut to dig the surface of the connecting member and the nut. .

In addition, the secondary battery module is an energy source for driving a motor of the device in a device that operates by using a motor such as a hybrid electric vehicle (HEV), an electric vehicle (EV), a wireless cleaner, an electric bicycle, an electric scooter, and the like. Can be used as

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is an exploded perspective view illustrating a rechargeable battery module according to a first embodiment of the present invention.

Referring to the drawings described above, the secondary battery module 100 according to the present embodiment includes a plurality of electrode terminals 21 and 22 including the positive terminal 21 and the negative terminal 22 protruding to the outside. The battery cell 11 and the electrode terminals 21 and 22 of the neighboring unit cell 10 are electrically disposed between the unit cell 10, the unit cells 10 to form a flow path of the heat transfer medium. A connecting member 30 for connecting, nuts 25 and 26 for fixing the connecting member 30, and washers 32 and 33 interposed between the connecting member 30 and the nuts 25 and 26. do.

The unit cell 10 according to the present embodiment has a rectangular shape and includes a case 15 accommodating an electrode group and a cap plate 17 enclosing the case 15. However, in the present embodiment, the rectangular battery is described as an example, but the present invention is not limited thereto, and the unit battery 10 may be formed in a cylindrical shape or other shape.

The cap plate 17 is provided with electrode terminals 21 and 22 protruding outwardly, and the electrode terminals 21 and 22 have threads formed on an outer circumferential surface thereof so that the nuts 25 and 26 can be fastened.

In addition, a gasket 23 is provided between the cap plate 17 and the electrode terminals 21 and 22 to insulate the cap plate 17 and the electrode terminals 21 and 22. The nut 25 is installed on the gasket 23 through the washers 31 so as to support the electrode terminals 21 and 22.

Each of the unit cells 10 constituting the battery module is arranged such that the positive electrode terminal 21 and the negative electrode terminal 22 of the neighboring unit cells 10 are crossed so that they can be connected in series. The connection member 30 is provided between the positive electrode terminal 21 and the negative electrode terminal 22 of the unit cell 10 adjacent thereto.

The nut 26 is installed on the connection member 30 so that the connection member 30 can be fixed. In addition, washers 32 and 33 having disc shapes are installed between the nuts 25 and 26 and the connecting member 30 to improve the fastening force of the nuts 25 and 26.

2 is a partial cross-sectional view illustrating a part of a rechargeable battery according to a first exemplary embodiment of the present invention.

Referring to the time limit drawings, the secondary battery 10 according to the present embodiment includes a case 15, a cap plate 17 sealing the case 15, and an electrode terminal 21 protruding outward. Include. In addition, a gasket 23 is installed between the electrode terminal 21 and the cap plate 17, and a washer 31 is installed on the gasket 23.

In addition, the electrode terminal 21 is provided with a connecting member 30 for electrically connecting the neighboring unit cells 10, and nuts on the upper and lower surfaces of the connecting member 30 via washers 32 and 33. (25, 26) are provided.

In addition, at least one protrusion 32a, 33a is formed on a surface where the washers 32, 33 are in contact with the connection terminal 30. The protrusions 32a and 33a according to the present embodiment are formed in a wedge shape so that when the nuts 25 and 26 are tightened, they are pressed by the nuts 25 and 26 to dig into the surface of the connecting member 30. do. However, the shapes of the protrusions 32a and 33a are merely examples of the present embodiment, and the present invention is not limited thereto.

As shown in FIG. 3, the washer 32 includes a through hole 32b formed at the center thereof to allow the electrode terminal 21 to be fitted therein. The protrusion 32a is continuously formed along the circumferential direction of the washer 32 to form a round band.

Therefore, when the washers 32 and 33 are pressed by the nuts 25 and 26 to be in close contact with the connecting member 30, the projections 32a and 33a of the washers 32 and 33 are connected to the connecting member 30. By digging the surface, the washers 32 and 33 and the connecting member 30 are brought into surface contact. Therefore, current can flow freely through the portion making surface contact, and contact resistance is minimized.

4 is a cross-sectional view showing a part of the unit cell 10 according to the second embodiment of the present invention. Referring to the drawings described above, the unit cell according to the present embodiment is the cap plate 47 and the cap plate 47 for sealing the case 44 and the case 44 in the same manner as the unit cell of the first embodiment It includes an electrode terminal 21 protruding outward.

The electrode terminal 21 is provided with a connection member 40 for electrically connecting the electrode terminals 21 of neighboring unit cells. And nuts 45 and 46 for supporting the connection member 40 are provided on the upper and lower portions of the connection member 40. And between the connecting member 40 and the nuts (45, 46) are provided with washers (42, 43) for improving the fastening force of the nuts (45, 46).

Here, the washers 42 and 43 are formed in a disc shape having a through hole formed in the center thereof, and protrusions 42a and 43a are formed on both sides of the disc.

Therefore, when the washers 42 and 43 are pressed by the nuts 45 and 46, the protrusions 42a and 43a are in close contact with the surfaces of the connecting member 40 and the nuts 45 and 46. When the washers 42 and 43 are further pressed by the nuts 45 and 46, the protrusions 42a and 43a dig into the surfaces of the nuts 45 and 46 and the connecting member 40.

Therefore, at the portions where the projections 42a and 43a are formed, the washers 42 and 43 are in surface contact with the nuts 45 and 46 and the connecting member 40, and the contact resistances generated at the surfaces where the members are in contact with each other are minimized. can do.

5 is a perspective view showing a washer according to a third embodiment of the present invention.

The washer 50a according to the present embodiment is a member installed between the connecting member 30 and the nuts 25 and 26 shown in FIG. 1 of the present invention, and the secondary battery module according to the present embodiment is the washer 50a. All structures except) have the same structure as the battery module of the first embodiment.

A through hole 50b into which the electrode terminal 21 is fitted is formed at the center of the washer 50, and a minute protrusion 50 having a horn shape is formed on the surface of the washer 50.

Although the protrusion 50a is illustrated as having a conical shape in FIG. 5, this is only an example of the present embodiment, and the present invention is not limited thereto. Therefore, the protrusion 50a may be formed in various forms such as cones, square pyramids, and triangular pyramids.

In addition, the protrusion 50a may be formed only on one surface of the washer 50 in contact with the connection member 30, and may be formed in both the surface in contact with the connection member 30 and the surface in contact with the nuts 25 and 26. have.

As such, the minute protrusions 50a are formed on the washer 50, so that when the washers 50 are pressed by the nuts 25 and 26, the protrusions 50a are in close contact with and adjacent to the neighboring members. The part is in surface contact with the neighboring member. In addition, when the washer 50 is further pressed by the nuts 25 and 26, the protrusion 50a penetrates the surface of the heat-sealing member 30 or the nuts 25 and 26 so that these members face more stably. You can make contact.

The secondary battery module of the present invention is an energy source for driving a motor of the device in a device that operates using a motor, such as a hybrid electric vehicle (HEV), an electric vehicle (EV), a wireless cleaner, an electric bicycle, an electric scooter, and the like. Can be used as.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to

As described above, according to the embodiment of the present invention, a protrusion is formed on the washer installed between the connecting member and the nut, and the protrusion is in close contact with the surface of the connecting member or the nut to penetrate the surface of the members so that these members are stably. Surface contact is possible.

Claims (9)

A plurality of unit cells including an electrode terminal protruding outward; A connection member electrically connecting the unit cells; A nut fastened to the electrode terminal to support the connection member; And A washer interposed between the nut and the connection member and having protrusions formed on at least one surface thereof; Secondary battery module comprising a. According to claim 1, The protrusion is formed on a surface in contact with the connecting member. According to claim 1, The protrusion is a secondary battery module formed on both sides of the washer. According to claim 1, The protrusion is a secondary battery module having a sharp pointed end. According to claim 1, The protrusion is a secondary battery module is formed continuously in the circumferential direction of the washer. According to claim 1, The protrusion is a secondary battery module is formed in a horn shape. According to claim 1, The protrusion is pressed by the nut to the secondary battery module to penetrate the surface of the connection member. The method of claim 3, wherein The protrusion is pressed by the nut to the second battery module to penetrate the surface of the connecting member and the nut. According to claim 1, The secondary battery module is a secondary battery module for driving a motor.

Images