KR100728216B1 - Secondary battery module - Google Patents

Abstract

In order to prevent deformation of the end plate, the present invention provides a plurality of unit cells arranged in a stack, an end plate installed at an outermost side of the unit cells to fix the unit cells, and a connection member connecting the end plates. It includes, at least one end plate provides a secondary battery module that is slidably coupled to the connection member.

Secondary battery module, end plate, sliding, connecting member, through groove

Description

Secondary Battery Module {SECONDARY BATTERY MODULE}

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

2 is an exploded perspective view illustrating a structure for supporting secondary batteries according to a first embodiment of the present invention.

3 is a perspective view illustrating a rechargeable battery module according to a second exemplary embodiment of the present invention.

The present invention relates to a secondary battery module configured by connecting a plurality of unit cells. More particularly, the present invention relates to a secondary battery module having an improved structure for supporting unit cells.

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 mobile 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, and examples of the secondary battery include a cylindrical shape and a square shape. A large capacity secondary battery in which a plurality of high output secondary batteries are connected in series is used for an apparatus requiring a large power, such as an electric vehicle.

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 group in which a positive electrode and a negative electrode are positioned with a separator interposed therebetween, a case having a space in which the electrode group is embedded, and a case coupled to the case to be sealed and electrically connected to the electrode group. A cap assembly with terminals.

Each unit cell is usually arranged at regular intervals in the housing and connects the terminals of each unit cell to form a battery module.

Herein, the battery module has a structure in which a plurality of unit cells are fastened to one battery module for stability.

That is, a plurality of unit cells are stacked and arranged, two end plates are disposed on the outermost sides of the unit cells, and the end plates are supported by a plurality of rod-shaped connecting rods, and the unit cells are fastened to the battery module.

In general, the connection rod is formed with a flange portion on one side and a screw processing portion is formed on the other side. And the end plate is formed with a through hole through which the connecting rod is inserted. Therefore, the nut is fastened to the threaded portion of the connecting rod in the state that the connecting rod is inserted into the through hole of the end plate so that the flange portion and the nut support the end plate, respectively.

On the other hand, when the battery module is used for a long time, a swelling phenomenon in which the inside of the unit battery swells may occur. In this case, the unit battery is expanded to press the end plate. In addition, the pressing force increases as the unit cell repeats charging and discharging, and a problem arises in that the end plate is deformed by the increased pressing force.

When bending deformation occurs in the end plate, the nut that secures the connecting rod or the connecting rod to the end plate is unevenly contacted with the end plate, and stress is concentrated at the unevenly contacted portion. In this way, when the stress is concentrated, the parts may be deformed or, in serious cases, broken in the areas where the stress is concentrated.

In addition, when a stress above the yield point acts on the end plate and the end plate is bent due to plastic deformation, there is a permanently concentrated portion of stress and a greater risk of deformation or breakage of such portion.

In order to solve such a problem, if the connection rod or the end plate is made thick, the overall weight of the secondary battery module increases, causing the performance of the device in which the battery module is mounted.

In particular, in the case of a secondary battery for driving a motor used in a hybrid electric vehicle (HEV), an electric bicycle, an electric scooter, and the like, it is important to reduce the self-load of the battery in order to improve the performance of the devices. Increasing the thickness is an increase in the weight of the battery module, there is a problem that is difficult to apply for driving the motor power is reduced compared to the weight.

Accordingly, the present invention has been made to solve the above problems, it is an object of the present invention to provide a secondary battery module that can prevent the deformation of the end plate by improving the structure for supporting the end plate.

In order to achieve the above object, a battery module according to an embodiment of the present invention includes a plurality of unit cells arranged in a stack, an end plate installed at an outermost side of the unit cells and fixing the unit cells, and the end plates. And a connecting member for connecting, wherein at least one end plate is slidably coupled to the connecting member.

The connecting member may have a long through groove formed in the longitudinal direction of the connecting member, and the supporting member may be provided with a supporting member inserted into the through groove to support the end plate.

The side surface of the end plate is formed in a threaded groove, the support member may be made of a bolt coupled to the groove. Here, the support member is tightened to strongly press the connecting member to the end plate when it is fastened to the screw groove formed in the end plate.

In this structure, the support member is coupled to the side surface of the end plate, the support member is in close contact with the connection member can be fixed to the connection member by the frictional force.

A protrusion for supporting the support member may be formed on an inner side surface of the through groove, and the protrusion may be formed in plural to support the support member so that the support member slides in stages.

The connecting member may have a flange portion formed at one end thereof, and a through groove may be formed at an edge of the opposite end thereof. Therefore, one end plate is fixed to the flange portion and the other end plate may be fixed by a support member installed in the through groove.

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, an embodiment of the present invention will be described with reference to the accompanying drawings.

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

Referring to the drawings described above, the battery module 100 according to the present embodiment is disposed between a plurality of unit cells 11 and the unit cells 11 that are stacked and arranged to provide a flow path of a heat transfer medium. The partition 12 is included.

In the following embodiment, the case where the rectangular unit cell 11 is used as the unit cell 11 will be described. However, the present invention is not limited thereto, and the present invention may be applied to unit cells having various shapes such as a cylindrical shape.

Each unit cell 11 is formed of a secondary battery having a conventional structure in which a group of electrodes laminated in a case is disposed between a positive electrode and a negative electrode in a case to charge and discharge a predetermined amount of electricity.

Battery partition walls 12 are provided between the unit cells 11 to maintain a gap between the unit cells 11 and to distribute heat transfer medium between the unit cells 11.

At the outermost sides of the stacked unit cells 11, a pair of end plates 21 and 23 for pressing the unit cells 11 inward are provided. The end plates 21 and 23 are supported by the connecting member 30. The connecting member 30 is formed at one end of the rod part 31 and the rod part 31 having a flat rectangular bar shape. It includes a flange portion 32 and a through groove 35 formed on the opposite edge of the flange portion 32.

The flange portion 32 has a structure having a larger cross-sectional area than the rod portion 31 so as to be in contact with the end plate to support the end plate.

And the through groove 35 is provided with a support member 37 for supporting the end plate 23, the support member 37 is fixed to the end plate 23 through the through groove 35. And the through groove 35 is made of a groove 35 formed long in the longitudinal direction of the connecting member 30 so that the support member 37 can flow by sliding.

As shown in FIG. 2, a through hole 21a into which the rod part 31 is inserted is formed at one end plate 21, and the other end plate 23 is a through groove 35 formed in the connecting member 30. A screw groove 23a is formed so that the support member 37 passed through the fastener can be fastened.

In addition, the one end plate 21 having the through hole 21 a is formed in a structure in which both edges thereof are formed wider than the unit cell 11 so as to protrude to the outside of the unit cell 11. 21a) is formed.

The connecting member 30 is inserted into the through hole 21a, and the flange 32 of the connecting member 30 is inserted deeply in contact with the outer surface of the one end plate 21. The connecting member 30 is formed so that the opposite end of the flange portion 32 passes through the other end plate 23, and the through groove 35 formed in the connecting member 30 is formed on the other end plate. It is provided so that the groove 23a and a hole may overlap.

In this state, the support member 37 is installed in the through groove 35, and the support member 37 according to the present embodiment passes through the through groove 35 formed in the connection member 30 to end plate 23. It is fastened to the screw groove 23a formed in the.

The support member 37 according to the present exemplary embodiment is made of a bolt, and the support member 37 is screw grooves in a state in which the end plate 23 having the screw grooves 23a is pressed toward the unit cell 11. It is coupled to (23a), in this case, the head of the support member 37 is tightly tightened the support member 37 so that the close contact with the connecting member 30 so that the end plate 23 is fixed to the connecting member (30). do.

Therefore, in the secondary battery module 100 according to the present embodiment, one end plate 21 is fixed by the flange 32 of the connection member 30, and the other end plate 23 is connected by the support member 37. It is fixed to the member 30.

At this time, the head of the support member 37 is in close contact with the connection member 30 by the friction force acting between the connection member 30 and the support member 37, the support member 37 to the connection member 30 Can be fixed.

In addition, the through groove 35 is formed to be long in the longitudinal direction of the connecting member 30 so that the support member 37 may flow along the through groove 35.

Therefore, when the unit cell 11 swells in the unit cell 11 in the process of repeatedly charging and discharging, and the unit cell 11 swells to press the end plates 21 and 23, the end plate When the force for pushing the 21 and 23 is greater than the frictional force between the one end plate 23 and the support member 37, the one end plate 23 is pushed outward.

When the end plate 23 is pushed outward, the pressing force acting on the end plate 23 decreases, and when the pressing force acting on the end plate 23 decreases to be equal to the wear force, the end plate 23 again returns. It may be fixed by the support member 37.

With this structure, when excessive force is applied to the end plates 21 and 23, the end plate 23 can slide and be pushed out to reduce the force acting on the end plates 21 and 23, so that the end plates 21 and 23 can be reduced. Can easily prevent deformation and breakage.

2 is a perspective view illustrating a battery module according to a second embodiment of the present invention.

Referring to the drawings described above, the battery module 200 according to the present embodiment includes a battery partition wall 12 installed between the unit cell 11 and the unit cell 11, the unit cells 11 of the At the outermost end plates 41 and 42 supporting the unit cells 11 are installed.

The end plates 41 and 42 are fixed by the connecting member 40, and the connecting member 40 is stored at one end of the rod portion 41 and the rod portion 41 formed of a flat rectangular bar. A) a bent portion bent in the shape of a 42, and a through groove 45 formed in an elongated edge on the opposite edge of the bent portion 42.

The bent part 42 is hooked to one end plate 41, and in this state, a screw is installed to penetrate the bent part 42 to the end plate 41 so that the end plate 41 and the bent part 42 are formed. It is fixed.

And the through groove 45 formed in the connecting member 40 is provided with a support member 47 made of screws in a state in which the hole is overlapped with the screw groove (not shown) formed in the other end plate 43. On the other hand, the through groove 45 is formed with a projection (45a) to support the support member 47 installed in the through groove (45).

Therefore, the support member 47 is screwed with the end plate 43 and fixed to the end plate 43, and the support member 47 is screwed with the end plate 43 by passing through the through groove 45 and is supported. The member 47 is tightly fastened to the end plate 43 so as to be in close contact with the connecting member 40, so that a strong friction force acts between the connecting member 40 and the supporting member 47.

With this structure, the support member 47 is fixed by the friction force to the connecting member 40 and the protrusions 45a formed in the through groove 45. In addition, the protrusions 45a are formed at a predetermined interval in the longitudinal direction of the through groove 45 so that the support member 47 can slide in stages.

Meanwhile, when the swelling phenomenon occurs in the unit cell 11 and the unit cell 11 swells, the unit cells 11 press the end plates 41 and 43, and at this time, the one end plate 43 The fixed support member 47 is also pressed outward.

The pressing force acting on the support member 47 is greater than the frictional force acting between the connecting member 40 and the support member 47, and the support member 47 and the protrusion 45a cause elastic deformation, thereby supporting the support member 47. If a pressing force large enough to escape between the projections 45a is applied, the support member 47 is pushed outward through the projection 45a, and at this time, the end plate 43 fixed to the support member 47 is also outwardly. It is pushed out.

When the end plate 43 is pushed outward by the distance between the projections 45a, the interval between the unit cells 11 is slightly widened, so that the pressing force acting on the end plate 43 is reduced and the end plate 43 is supported by the supporting member ( It is supported and fixed again by the friction force acting between the 47 and the connecting member 40 and the projection 45a formed in the through groove 45.

By repeating this action, when a pressing force of a predetermined level or more is applied to the end plates 41 and 43, one end plate 43 may be pushed outward to prevent the end plates 41 and 43 from being deformed.

The battery module of the present invention is a device for operating by using a motor such as a HEV (hybrid electric vehicle), an EV (electric vehicle), a cordless cleaner, an electric bicycle, an electric scooter, and the like for driving energy of the motor of the device. Can be used as a circle.

In the above description of the preferred embodiment of the present invention, 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 the range of.

Thus, according to the present invention, the end plate is installed in a structure that can slide with respect to the connecting member can be easily prevented deformation of the end plate by reducing the force acting on the end plate.

Claims (8)

A plurality of unit cells; An end plate installed at the outermost sides of the unit cells to fix the unit cells; And A rod-shaped connecting member connecting the end plates; Including, The connecting member is formed with a long through groove formed in the longitudinal direction of the connecting member, the through groove is provided with a support member fitted to the through groove to support the end plate, the support member is slid in the longitudinal direction of the through groove Possible secondary battery module coupled. delete According to claim 1, The support member is in close contact with the connection member is a secondary battery module is fixed to the connection member by a friction force. According to claim 1, The supporting member is coupled to the side surface of the end plate secondary battery module. The method of claim 4, wherein The side surface of the end plate is formed in a threaded groove, the support member is a secondary battery module consisting of a bolt coupled to the groove. The method according to any one of claims 1 or 3 to 5, A secondary battery module having a plurality of protrusions on the inner surface of the through groove to support the support member. According to claim 1, The connecting member is a secondary battery module is formed with a flange portion at one end, the through groove is formed on the opposite edge of the flange portion. According to claim 1, The secondary battery module is a secondary battery module for driving a motor.

Images