KR20070006956A - Secondary battery module - Google Patents

Abstract

Provided is a secondary battery module, which shows a high capacity from a plurality of unit cells connected to each other, and has a simplified connection structure to reduce the time and labor required to perform the connection or exchange of unit cells. The secondary battery module comprises a plurality of unit cells(11) and a connection member(50) electrically connected between one terminal(14) and another terminal(15). In the secondary battery module, the connection member comprises: an outer portion(52) having a through hole(51) so that it is inserted to a terminal; an intermediate portion(53) having a smaller thickness as compared to the outer portion and connecting a gap between one outer portion and another outer portion; and a channel-like groove(54) formed on at least one surface of the intermediate portion.

Description

Secondary Battery Module {SECONDARY BATTERY MODULE}

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

2 is a side cross-sectional view showing a partial configuration of a rechargeable battery module according to an embodiment of the present invention.

3 is a cross-sectional view of a rechargeable battery module according to an exemplary embodiment of the present invention.

4 to 8 are cross-sectional views of a rechargeable battery module according to another exemplary embodiment of the present invention.

9 is a side cross-sectional view illustrating a part of a configuration of a secondary battery module according to still another embodiment of the present invention.

The present invention relates to a secondary battery module. More particularly, the present invention relates to a secondary battery module having improved connection structure between unit cells in a high output large capacity battery.

In general, 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 phones, notebook computers, and camcorders, and large-capacity secondary batteries are widely used as power sources for driving motors in hybrid vehicles.

The secondary battery is manufactured in various shapes. Representative shapes of the secondary battery include cylindrical and rectangular shapes. A plurality of high-output secondary batteries described above are connected in series so as to be used for driving a motor such as an electric vehicle, which requires a large power, thereby forming a large capacity secondary battery.

As described above, 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 unit cell includes an electrode assembly having a positive electrode and a negative electrode interposed between the separator, a case having a space in which the electrode assembly is embedded, a cap assembly coupled to the case and sealing the protruding portion. And positive and negative terminals electrically connected to the positive and negative current collectors provided in the electrode assembly.

In the case of the rectangular battery, each of the unit cells cross-aligns each of the unit cells such that the positive electrode terminal and the negative electrode terminal protruding from the top of the cap assembly alternate with the positive electrode terminal and the negative electrode terminal of the neighboring unit cell, and the threaded negative electrode terminal A battery module is constructed by connecting and connecting a conductive member through a nut between positive electrode terminals.

That is, each terminal is made of a male screw, the nut is first fastened to each terminal. A conductive member for electrically connecting the positive terminal of one unit cell and the negative terminal of the next unit cell is fitted on the nut, and the nut is fastened again to fix the conductive member on the conductive member.

However, in the conventional structure described above, in the configuration of one battery module by connecting several to many tens of unit cells, four nuts must be fastened to each terminal in order to connect the conductive members, which makes the operation difficult and time consuming. There is a problem.

In addition, in the unit cells of the secondary battery module, if an abnormality occurs in some unit cells, in order to replace the unit cells, the coupling state between the unit cells must be released and then coupled again. In this case, the nut is substantially connected to the terminal. In this case, it is also inconvenient to reduce the workability because the work is inconvenient.

In addition, since the conductive member is conventionally formed in a plate shape, when the conductive member is in contact with the terminal, the contact area cannot be large. Therefore, the electrical conductivity between the terminal and the conductive member is increased. There is a problem to drop.

In particular, in the case of a large-capacity secondary battery for a HEV (Hybrid Electric Vehicle), the number of unit cells reaches several dozens, thereby increasing the above-mentioned problem.

Therefore, the present invention is to solve the above problems, an object of the present invention is to configure a large capacity battery module by connecting a plurality of unit cells, simplifying the connection structure of the unit cell is required for the connection and replacement work It is to provide a secondary battery module that can reduce the time and effort.

In addition, another object of the present invention is to provide a secondary battery module capable of increasing electrical conductivity by maximizing contact area with terminals when connecting unit cells.

In addition, another object of the present invention is to provide a secondary battery module that is easy to install regardless of tolerances for the intervals between the unit cells.

In order to achieve the above object, the secondary battery module of the present invention includes a battery module including a connector electrically connected between a plurality of unit cells and terminals of the unit battery, wherein the connector is formed by inserting a through-hole into the terminal. And an outer portion formed to have a thickness smaller than the outer portion, and an intermediate portion connecting the outer portions, and a channel-shaped groove formed on at least one surface of the intermediate portion.

The connector is connected to the positive terminal or the negative terminal of the unit cell of one side and the negative terminal or the positive terminal of the neighboring unit cell, so that the through hole formed in the outer portion of the connector is preferably formed in accordance with the interval between the terminals of the unit cell. .

In addition, the through hole formed in the connector has a cross-sectional shape the same as the cross-sectional shape of the terminal, the size is the same as or slightly smaller than the size of the terminal, the connector is fastened to the terminal by the terminal fitting type It is desirable to be in close contact with and to increase the tightening force.

The unit cell may include an electrode assembly having a positive electrode plate and a negative electrode plate interposed therebetween, a case having a space portion in which the electrode assembly is embedded, a cap assembly coupled to the case and sealing it, and the positive and negative electrode plates. And a positive electrode terminal and a negative electrode terminal which are electrically connected to the whole and protrude outside the cap assembly.

In addition, an insulator of an insulating material may be further inserted between the cap assembly and the connector.

On the other hand, the through-hole inner circumferential surface of the terminal or the connector is preferably formed with a coating film of excellent electrical conductivity such as silver on the surface to increase the conductivity.

In addition, the through hole of the connector corresponding to the terminal and the terminal may have a cross-sectional structure having a rectangular shape or a circular shape, but is not particularly limited thereto and may maximize the structure or contact area of a polygonal shape such as a pentagon or a hexagon. Forms that can be used, such as spline or cross, will also be applicable.

In addition, one or two grooves formed in the middle portion of the connector may be formed at intervals.

Accordingly, the intermediate part can be bent more easily, so that even if the interval between terminals of neighboring unit cells is different according to the assembly tolerance, the intermediate part of the connector can be bent to match the gap between the through holes with the gap between the terminals. .

The groove may be formed in an arc shape or a triangular or quadrangular shape and is not particularly limited.

On the other hand, in the battery module according to the present invention, the through hole of the connector has a structure in which the size is continuously reduced along the traveling direction to form an inclined surface, and the terminal also has the same slope as the inner circumferential surface of the through hole in the longitudinal direction. The structure is processed with

In addition, the connector may be fixed by welding with the terminal in the state fitted to the terminal through the through-hole.

Here, 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.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

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

Looking at the structure of each unit cell 11 constituting a large-capacity battery module 10 with reference to the drawings described above, the electrode assembly (not shown), the positive electrode plate and the negative electrode plate is located between the separator and the electrode assembly A case 12 having a space portion therein is installed, a cap assembly 13 coupled to the case 12 to seal the case, electrically connected to a current collector of the positive and negative electrode plates, and protrude out of the cap assembly 13. Positive and negative terminals 14 and 15.

The case 12 is made of a conductive metal such as aluminum, an aluminum alloy or nickel plated steel, and the shape is made of a cube or other shape having an inner space in which the electrode assembly is located.

In the present embodiment, each of the unit cells 11 has a structure in which two terminals (the positive electrode terminal 14 and the negative electrode terminal 15) protrude from the cap assembly 13 while keeping a gap therebetween.

Each unit cell 11 having the above-described structure is placed in a state in which the terminals 14 and 15 face upwards to form a large capacity battery module 10, and an upper portion of the cap assembly 13 of one side unit cell 11. The positive electrode terminal 14 and the negative electrode terminal 15 protruding from each other are alternately arranged alternately with the positive electrode terminal 14 and the negative electrode terminal 15 of the neighboring unit cell 11.

Accordingly, the positive electrode terminal and the negative electrode terminal are formed on both sides of the center of the unit cell 11, and terminal terminals are arranged at regular intervals. Can be understood as a single line.)

In the battery module having the above structure, the secondary battery is a connector for electrically connecting the positive electrode terminal 14 and the negative electrode terminal 15 between neighboring unit cells 11 in order to connect the unit cells 11 in series. 50 is mounted.

The connector 50 has a through hole formed so as to be fitted to the terminals 14 and 15 of each unit cell, and is formed to have a thickness smaller than a thickness of the outer portion, and an intermediate portion connecting the outer portion. A part includes a plurality of grooves in a channel form spaced apart from one surface of the middle part.

The through hole 51 formed in the outer portion 52 of the connector 50 has the same cross-sectional shape as the cross-sectional shape of the terminals 14 and 15, and the size is the same as or slightly smaller than the size of the terminal. The connector 50 is forcibly fastened to the terminals 14 and 15.

Accordingly, the connector 50 is forcibly inserted into the through hole 51 of the connector 50 in the process of being fastened to the terminal, and the inner circumferential surface of the through hole of the connector 50 and the outer circumferential surface of the terminals 14 and 15. This strongly adheres to maintain the fixed state by the mutual frictional force.

That is, while the terminals 14 and 15 are inserted into the through holes 51 of the connector 50, the inner surface of the through hole 51 is in contact with the outer surface of the terminal, and at this time, the connector 50 is connected with the friction force generated at the contact surface between the terminals 50. Is installed in the unit cell is maintained, and thus, by inserting the connector 50 into the terminal, it is possible to form the battery module 10 by simply electrically connecting each unit battery 11, and the installed connector 50 from the terminal The unit battery can be replaced easily by taking it out.

In order to insert the terminals 14 and 15 into the through hole 51 of the connector 50 or to pull the connector 50 out of the terminal, a separate jig or device such as a hammer may be used.

1 illustrates a state in which the connector 50 is installed in a unit cell. According to the above drawings, the anode terminal 14 of one unit cell 11 and the negative electrode of the unit cell 11 placed next are illustrated in FIG. The connector 50 is inserted into and electrically connected to the terminal 15, and the positive terminal 14 positioned in the other terminal column of the next unit cell 11 is the negative terminal 15 of the unit cell 11 placed next. And the connector 50 is connected through the whole unit cell 11 is connected in series.

In addition, as shown in FIG. 2, more preferably, an insulator insulator 40 is further inserted between the cap assembly 13 and the connector 50.

The non-conductor 40 is a material that does not conduct electricity, and is separately installed in the terminal as shown in FIG. 2, and a hole is formed in the center to be fitted to the terminal.

 By inserting the non-conductor between the connector 50 and the cap assembly, it is possible to reliably prevent the energization that may occur in the gap between the connector 50 and the cap assembly.

Here, the secondary battery has the above-described structure, so that the entire inner surface of the through hole 51 of the connector 50 is in contact with the terminal, and the contact area thereof is remarkably increased in comparison with the conventional art. Thus, the connector 50 and the terminal 14 are thus increased. It is possible to maximize the conductivity between.

In addition, in order to increase conductivity, the secondary battery further forms a coating film 30 made of a material having excellent electrical conductivity such as silver on the surface of the terminal and / or the inner surface of the through hole 51 of the connector 50.

On the other hand, the connector 50 has a through hole 51 is formed, the thickness of the intermediate portion 53 is connected between the outer portion 52 than the thickness (D) of the outer portion 52, the terminal (14, 15) is fitted (d) has a thin structure.

Accordingly, even if the intervals between the terminals 14 and 15 of the neighboring unit cells 11 are different according to the assembly tolerance, the middle portion 53 of the thinner connector 50 is easily bent and the terminals 14 and 15 are easily bent. ), And the connector 50 can be easily inserted between the terminals 14 and 15 by matching the gap between the through holes 51 of the connector 50.

In addition, the connector 50 has a plurality of grooves 54 are further formed in the intermediate portion 53 of the connector so that the intermediate portion 53 can be bent better.

The groove 54 formed in the intermediate portion 53 may be formed in an arc cross-sectional shape, but is not limited thereto. The groove 54 may be formed in various shapes such as an arc shape, a triangular shape, or a square shape.

3 and 4 illustrate a connector 50 having a structure in which a plurality of arcs or grooves 54 are formed in the middle portion 53, and FIG. 5 is another embodiment of the secondary battery module. The structure in which the triangular groove 54 is formed in the middle portion 53 is well illustrated.

Meanwhile, the connector 50 increases the bonding force by welding the terminals 14 and 15 exposed through the through hole 51 and the connector 50.

In the present embodiment, the through holes 51 of the terminals 14 and 15 and the connector 50 have a circular cross-sectional structure as mentioned above, but are not limited thereto. For example, as shown in FIGS. 6 to 8. Likewise, the cross-sectional structure or cross-sectional structure of the rectangular cross-sectional structure or spline shape may be made.

On the other hand, according to another embodiment of the secondary battery according to the penetration of the terminals 14 and 15 installed in the unit cell 11 and the connector 50 is fitted to the terminal for easy installation and separation of the connector 50 The holes 51 may be formed with slopes having the same angle in the longitudinal direction.

In the following description, the case where the cross-sectional structures of the terminals 14 and 15 and the through hole 51 are circular will be described as an example. However, the present invention is not limited thereto, and the above-described terminals and grooves of various cross-sectional structures may also be applicable.

That is, as shown in FIG. 9, the terminals 14 and 15 installed in each unit cell 11 have one end to the other end in the longitudinal direction (here, from the front end to the upper free end of the cap assembly 13). The inner diameter gradually decreases to form an inclined surface inclined at a predetermined inclination angle α, and the through hole 51 of the connector 50 into which the terminals 14 and 15 are fitted also has an inclination angle α toward the inner side. ), It is continuously smaller at the same angle as) and has a structure in which inclined surfaces of the same slope are formed.

Therefore, when the terminals 14 and 15 are inserted into the through holes 51 of the first connector 50, the terminal with the smaller diameter is inserted into the through hole 51 having the larger diameter. It can be inserted, and finally the outer peripheral surface of the terminals 14, 15 is in close contact with the inner surface of the through hole 51 of the connector 50, the connector 50 is fixed to the terminal by the frictional force.

Here, the inclined surfaces formed in the terminal and the through hole 51 may have a gradient by inclining only one side with respect to each center axis line, or both sides thereof may be symmetrically inclined to form a taper. However, the present invention is not particularly limited except that continuous inclined surfaces should be provided.

In FIG. 4, reference numeral 30 denotes a silver or the like coated on the surface of the terminal and / or the inner surface of the through hole 51 to increase the conductivity between the terminals 14 and 15 and the connector 50 as mentioned. It is a coating film, 40 is an insulator inserted between the connector 50 and the cap assembly 13 to insulate between the two members.

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 present embodiment, the connector can be easily fastened to the battery and can be easily separated during repair to replace the desired unit battery.

In addition, it is possible to maximize the performance of the battery by increasing the conductivity between each terminal and the connector of the unit cell.

In addition, as the connection between the unit cells is made through one component, the installation is easy and the amount of work can be reduced, and the cost increase through the reduction of the components is obtained.

Claims (16)

In the battery module comprising a connector that is electrically connected between a plurality of unit cells and the terminal of the unit cell, The connector is provided with a through hole formed in the outer portion is inserted into the terminal, An intermediate portion formed to a thickness smaller than the thickness of the outer portion to connect the outer portions, Channel-shaped grooves formed on at least one surface of the intermediate portion Secondary battery module comprising a. According to claim 1, The secondary battery module is welded between the through hole and the terminal. According to claim 1, The connector is a secondary battery module having a thickness of the intermediate portion that connects between the outer portion than the thickness of the outer portion. The rechargeable battery module of claim 1, wherein one or two grooves are formed at intervals. According to claim 1, The groove is a secondary battery module consisting of an arc shape or a triangular or rectangular shape. The secondary battery module of claim 1, wherein the through-holes have a small cross-sectional size toward the outer end thereof to form a slanted surface, and the terminal has a slanted surface corresponding to the channel along a longitudinal direction. According to claim 1, The through-hole formed in the outer portion of the connector is a secondary battery module formed in accordance with the interval between the terminals of the neighboring unit battery. According to claim 1, The through-hole formed in the connector has a cross-sectional shape of the secondary battery module having the same structure as the cross-sectional shape of the terminal. According to claim 1, The through hole is a secondary battery module that is fastened to the terminal by fitting. According to claim 1, A secondary battery module in which an insulator of an insulating material is inserted between the connector and the cap assembly. According to claim 1, The through-hole inner circumferential surface of the terminal or the connector is a secondary battery module formed with a coating film of a material having a higher electrical conductivity than the terminal or connector. According to claim 1, The through-hole and the corresponding terminal has a circular cross section of a secondary battery module. According to claim 1, The through-hole and the corresponding terminal has a rectangular cross-section of the secondary battery module. According to claim 1, The groove and the corresponding terminal is a secondary battery module having a spline cross section thereof. According to claim 1, The groove and the corresponding terminal has a cross-section cross-shaped secondary battery module. According to claim 1, The battery module is a secondary battery module for driving a motor.

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