KR100993128B1 - Electrical Connecting Member of Physical Contact Type and Battery Pack Containing the Same - Google Patents

Abstract

When the two or more secondary battery cells are mounted in the battery pack, the connecting member electrically connects the two or more battery cells arranged in the lateral direction by a physical contact method, corresponding to the outer shape of the battery cell terminal, A contact portion contacting the battery cell terminal with a predetermined width at a portion near its outer circumferential surface, an elastic portion tapered upward in the direction of the center axis with respect to the contact portion so as to provide a resilient ground force for the battery cell; For the physical contact of the connecting member, the pressing portion protruding at a predetermined height in the direction of the central axis with respect to the elastic portion and the indentation portion indented on the central axis to a depth smaller than the sum of the height of the elastic portion and the pressing portion It provides a connecting member of the structure.

Description

Electrical connecting member of physical contact method and a battery pack including the same {Electrical Connecting Member of Physical Contact Type and Battery Pack Containing the Same}

1 is an exploded view showing a coupling manner of batteries electrically connected by a metal plate which is a conventional connecting member;

2 is a schematic view of a battery pack with a metal plate and a protection circuit connected;

3 is a schematic view of a planar structure of a connecting member according to an embodiment of the present invention, and FIG. 4 is a side view of FIG. 3;

FIG. 5 is an enlarged view of a vertical cross-section and section B along line A-A of FIG. 3;

FIG. 6 is a perspective view of a form in which a connection member according to an embodiment of the present invention is attached to two battery cells, and FIG. 7 is a partial plan view of the battery cells of FIG. 6 mounted in a pack case;

8 and 9 is a schematic diagram of the structure to prevent the flipping of the connecting member according to the present invention against external impact.

The present invention is a connection member for electrically connecting two or more battery cells arranged laterally arranged by a physical contact method when mounting two or more secondary battery cells in a battery pack, more specifically, a battery cell A contact portion corresponding to the outer surface shape of the terminal, the contact portion being in contact with the battery cell terminal at a predetermined width at a portion near the outer peripheral surface thereof; An elastic portion tapered upward in a central axis direction with respect to the contact portion so as to provide an elastic traction force for the battery cell; A pressing portion protruding at a predetermined height in a direction of a central axis with respect to the elastic portion for physical contact of the connecting member with respect to the battery cell; And an indentation indented on a central axis to a depth smaller than the sum of the heights of the elastic portion and the pressing portion; It provides a connection member made of a structure comprising a.

As technology development and demand for mobile devices increase, the demand for secondary batteries as an energy source is rapidly increasing.

The secondary battery may be used in the form of a single battery, or in the form of a battery pack in which a plurality of unit cells are electrically connected, depending on the type of external device in which the secondary battery is used. For example, a small device such as a mobile phone can operate for a predetermined period of time with the output and capacity of one battery, while a medium or large size such as a notebook computer, a portable DVD, a small PC, an electric vehicle, a hybrid electric vehicle, or the like. Large devices require the use of secondary battery packs due to power and capacity issues.

The secondary battery pack is manufactured by connecting a protection circuit or the like to a core pack in which a plurality of unit cells are arranged in series and / or in parallel. In the case of using a square or pouch type battery as a unit cell, the wide surfaces thereof may be stacked to face each other, and then the electrode terminals may be easily connected by connecting members such as bus bars. Therefore, in the case of manufacturing a three-dimensional secondary battery pack having a hexahedral structure, a square or pouch type battery is advantageous as a unit cell.

On the other hand, the cylindrical battery generally has a larger capacitance than the square and pouch cells, but due to the external characteristics of the cylindrical battery is not easy to arrange in a laminated structure. However, when the shape of the secondary battery pack has a linear or plate-like structure as a whole, there is a structural advantage over the square or pouch type.

Therefore, in the case of a notebook computer, a portable DVD, a small PC, etc., a secondary battery pack in which a plurality of cylindrical batteries are connected in parallel and in series is used. As the core pack structure used in such a secondary battery pack, for example, a linear structure of 2P (parallel) -3S (serial), a plate structure of 2P-3S, a linear structure of 2P-4S, a plate structure of 2P-4S, and the like. Is being used.

The parallel connection structure is achieved by arranging two or more cylindrical cells adjacent in their lateral directions with the electrode terminals oriented in the same direction, and welding them to the connecting member. Such parallel cylindrical cells are also referred to as "banks".

In series connection structure, two or more cylindrical cells are arranged in a lateral direction while two or more cylindrical cells are arranged in a long manner so that electrode terminals of opposite polarities are continuous or the electrode terminals are arranged in opposite directions. Arranged adjacent to each other, the welding is performed by the connecting member.

In the electrical connection of such cylindrical cells, spot welding is generally performed using a thin connecting member (for example, a metal plate) such as a nickel plate.

FIG. 1 is a schematic view showing a state in which a secondary battery pack having a plate-like structure of 2P-3S is completed in an electrical connection work by spot welding. Figure 1 shows the coupling relationship of the secondary battery pack of the plate-like structure of 2P-3S for convenience of understanding as an exploded view.

As in FIG. 1, three cell pairs of cells 20, 21, each connected in parallel, are connected in series through a metal plate 30 to form a core pack 10.

2 shows a schematic diagram of the secondary battery pack 50 in a state where assembly is completed. For convenience of description, the pack case is omitted.

As shown in FIG. 2, each of the cells 20 and 21 is connected to the protection circuit module 90 through the positive lead 60 and the negative lead 70 and the FPCB 80 connected to the metal plate 30. It is. The electrical connection of the protection circuit module 90 to the metal plate 30 is mainly done by soldering.

In general, the secondary battery pack repeatedly performs a lot of charging and discharging during the use process, and lithium secondary batteries having a safety problem under conditions such as external shock, dropping, bed penetration, overcharge, overcurrent, etc. are used as unit cells. In order to solve these safety problems, safety devices such as protection circuit modules are added. The safety device secures the safety of the pack by acquiring information such as voltage at a corresponding connection portion of the secondary battery pack and performing a predetermined safety process. Therefore, when the connection state of the site is variable, for example, when the resistance value of the connection site is changed by vibration or the like, due to the inaccuracy of the detection information, the safety device cannot perform the desired process. Therefore, in general, the electrical connection between the battery cell and the protection circuit in the secondary battery pack is made by soldering or the like.

In addition, in order to construct a high-output, high-capacity secondary battery pack, it is necessary to connect a plurality of battery cells in series or in parallel. In order to maintain the performance of the secondary battery pack uniformly, it is possible to minimize the change in resistance of the connection part. Coupling is required. The electrical connection between these battery cells is typically made through soldering or welding, preferably spot welding.

However, a welding or soldering process between battery cells has the following problems. In particular, the welding or soldering process requires a skilled skill and know-how of the operator, and acts as a factor that inhibits the production efficiency at a complicated production process and a high cost. In addition, in the process of directly welding or soldering to the battery cell, such as causing an internal short circuit of the battery threatens the safety of the battery and increases the defective rate of the product.

Meanwhile, in battery packs using primary batteries, various attempts have been made to the electrical connection structure of the connection method. For example, Korean Patent Registration No. 0413381 discloses a technology for forming conductive coils at both ends of left and right sides of a battery case for electrical connection of a battery, and US Patent Registration No. 5827619 provides elasticity of a battery pack. Disclosed is a technical description of making an electrical connection by installing a bent metal plate.

However, the above technologies have a problem in that the connection member must have sufficient elasticity to fix the battery cell and to make stable connection with the electrode terminal. In particular, in the technique using the conductive coil, the electric resistance is inevitably increased because the cross-sectional area of the wire constituting the coil is narrow and the connection length is relatively long. May inhibit. In addition, the technology using the metal plate bent to have the elasticity, due to excessive force or repeated use in the process of inserting the battery cell into the pack case, the metal plate loses elasticity or is destroyed, when the battery cell is subjected to external impact Deviation or disconnection may occur.

In addition, the connection member as described above has a limitation in that it is applicable to the secondary battery pack as described above due to the variable connection state at the corresponding site.

Therefore, when manufacturing the secondary battery pack, it is possible to replace the connection method through welding, soldering, etc., which threatens the stability of the battery and requires a complicated work process, and at the same time provides a technology for securing a stable connection structure between battery cells. There is a high need.

Accordingly, an object of the present invention is to solve the problems of the prior art as described above and the technical problems that have been requested from the past.

That is, an object of the present invention is to provide a connection member that can stably electrically connect two or more secondary battery cells without performing soldering, welding, or the like.

Still another object of the present invention is to provide a secondary battery pack manufactured by using the connection member.

The connecting member according to the present invention for achieving this object, when mounting two or more secondary battery cells in the battery pack, the electrical connection between the two or more battery cells arranged in the lateral direction by a physical contact method As a connecting member,

(a) a contact portion corresponding to the outer surface shape of the battery cell terminal, the contact portion being in contact with the battery cell terminal at a predetermined width in the vicinity of the outer peripheral surface thereof;

(b) an elastic portion tapered upward in a central axis direction with respect to the contact portion so as to provide a resilient traction force for the battery cell;

(c) a pressing portion protruding at a predetermined height in the direction of the central axis with respect to the elastic portion for physical contact of the connecting member with respect to the battery cell; And

(d) an indentation indented on a central axis to a depth smaller than the sum of the heights of the elastic portion and the pressing portion;

The terminal connection parts having a configuration including are electrically connected to correspond to the number of battery cells in the side array, and has a structure including a terminal part for circuit connection on one side.

Therefore, the battery pack including the connection member according to the present invention does not require a soldering and welding process for the electrical connection of the battery cell electrode terminals, and maintains a stable connection structure only by the assembly of the prefabricated members. It prevents the possibility of battery short-circuit that may occur during the process, and the resistance change of the connection part does not deviate from the reliability level even by an external impact, and at the same time facilitates the assembly process of the battery pack, and provides a stable bonding force between the battery cell electrode terminals. can do. In addition, when a failure occurs during the assembly or use of the battery pack, the battery cells can be easily separated, so that some of the battery cells constituting the battery pack due to the failure of some of the battery cells or the connection member has to be discarded. I can eliminate it.

In the present invention, the connection member may be a structure that is preferably manufactured as a single body by pressing and deforming one conductive plate. In view of conductivity, elasticity, and ease of processing, a metal plate may be used as a material of the connecting member. For example, the connecting member may form a contact part, an elastic part, a pressing part, and an indentation part by rolling a single metal plate. Can be prepared.

The battery cell may be a battery cell having a variety of structures, preferably a cylindrical battery cell. In the cylindrical battery cell, the positive electrode terminal is generally protruded at one end, and the battery case is configured to form the negative electrode terminal in an insulated state. In order to correspond to the end of the cylindrical battery cell, the terminal connecting portion is preferably made of a substantially disk structure, and the contact portion, the elastic portion, the pressing portion, and the indentation portion constituting the terminal connecting portion may have a structure having a concentric shape as a whole. .

The contact width of the contact portion with respect to the battery cell may correspond to the battery cell terminal with a predetermined width at a portion near the outer circumferential surface of the terminal connection portion, corresponding to the outer surface shape of the battery cell terminal. If the contact portion is too wide in the terminal connection portion, the elastic portion, the pressing portion, and the indentation portion are relatively small, and thus the elasticity of the desired terminal connection portion is difficult to secure. On the contrary, if the contact portion width is too small, the resistance of the contact portion is reduced by the narrow contact area. This increases, and also has the disadvantage that the electrical terminal is easily disconnected while the electrode terminal of the battery cell slightly out of position due to external impact or the like. Therefore, the contact width of the contact portion with respect to the battery cell is preferably 5 to 20% of the size based on the radius of the terminal connection portion.

In the present invention, the elastic portion may be made in a width of 20 to 60% based on the radius of the terminal connection portion, and if the width of the elastic portion is too large, the contact portion, the pressing portion, etc. are relatively small, and if it is too small, the desired It is not preferable because it is difficult to provide elastic force. In addition, the elastic part may have a structure in which the taper is inclined at an angle of 5 to 30 degrees based on one surface of the terminal connection part in order to provide stable elastic force when contacting the electrode terminal of the battery cell. If the inclination is too large, a strong pressure needs to be applied to the connection member when the battery cell is mounted on the pack case, so that the mounting operation is not easy and the connection member may be damaged during the mounting process or the use of the battery pack. Too small is undesirable because it may not provide the desired elastic force.

The pressing portion formed to protrude in the direction of the central axis with respect to the elastic portion has a predetermined height so that the desired elastic force can be induced in the elastic portion in a state where it is mounted on the pack case. It can be determined in the size of 30 to 60% on the basis.

On the other hand, when excessive shock or vibration is applied to the battery pack, the battery cell may greatly press the connection member, and the elastic part tapered to a predetermined inclination may be reversed. An indentation portion indented in the direction of the electrode terminal of the battery cell on the shaft is required. The indentation is preferably indented on the central axis to a depth smaller than the sum of the heights of the elastic portion and the pressing portion, and may be, for example, set at a size of 30 to 90% based on the total height of the connection member. Therefore, even if the battery cell excessively presses the connection member by an external impact, the side wall of the case and the battery cell are separated by the depth of the indentation portion, thereby preventing the elastic portion from being overturned. On the other hand, when the depth of the indentation portion is greater than the sum of the heights of the elastic portion and the pressing portion, the electrode terminal of the indentation portion is in contact with the battery cell so that the elastic force by the elastic portion is not induced.

In one preferred example, the elastic portion may be formed with two or more cutouts of a predetermined width in the direction of the central axis in order to adjust the elastic force. Of course, even when there is no cutout, the elastic force is exerted, but since the required elastic force may vary according to the type of battery pack, the cutout may be formed in the elastic part to appropriately adjust the elastic force. In addition, it is preferable that the cutout forms a symmetrical structure with respect to the central axis so that the elastic force can be exerted evenly without being oriented on one side of the elastic part. Such cutouts may be formed in various shapes, for example, may be formed in a swirl shape as an efficient structure for providing a flexible elastic force.

In some cases, at least one side of the connection member may have a structure in which a side extension part in which the terminal part is located is formed, and thus, it may be simply connected to a protection circuit. The structure of the terminal portion formed in the side extension portion is not particularly limited and the structure thereof varies depending on the type of member for connecting to the protective circuit.

The present invention also provides a battery pack for a notebook computer comprising the above connection member.

That is, the battery pack according to the present invention is a battery pack for a notebook computer having a structure in which a plurality of battery cells are arranged in an electrical connection and a row of batteries is arranged in a pack case, and battery cells are arranged in a lateral direction. Provided is a battery pack having a structure in which the connection member is used for electrical connection of a field (bank).

Specifically, a battery pack having a structure in which battery cells are mounted after mounting the connection member in a battery pack case for a notebook including at least one storage unit in which two or more secondary battery cells can be mounted adjacent to each other in a lateral direction. As a battery pack, the battery pack may be manufactured in a structure in which the connection member is coupled in an assembly manner such that the contact portion faces the electrode terminal on the sidewall of the sidewalls constituting the pack case.

In the battery pack, the connection member may be preferably used to connect the negative terminals of the bank to the negative electrode circuit of the pack case. This structure is a structure in which the connection member is positioned between the negative terminal of the bank and the side wall of the pack case, so that the negative terminal of the side wall and the bank is stably fixed and electrically connected by the elastic force of the elastic part.

In the present invention, the connecting member is not particularly limited as long as it is a material having electrical conductivity and elasticity, and it is preferable to use a metal sheet in view of ease of processing. Among them, it may be preferably made of a material selected from the group consisting of nickel, brass, aluminum, copper and optional alloys thereof.

The battery pack according to the present invention may be used throughout small and medium mobile devices, power tools, and the like, and may be particularly preferably used in battery packs for notebook computers, which generally use a cylindrical secondary battery as a unit battery.

Accordingly, the present invention also provides a notebook computer including the battery pack as a power source.

Since the general structure of the notebook computer and its manufacturing method and the like are known in the art, further description thereof will be omitted herein.

Hereinafter, the content of the present invention will be described with reference to the drawings, but the scope of the present invention is not limited thereto.

3 schematically illustrates a planar structure of a connecting member according to an embodiment of the present invention, and FIG. 4 illustrates a side view of FIG. 3. In addition, FIG. 5 shows an enlarged view of the vertical cross-sectional view and the portion B along the line A-A of FIG. 3.

Referring to these drawings, the connection member 100 according to the present invention is a connection member having a 2p structure, which is made of one metal plate, and two terminal connection portions 101 are connected to each other. Each terminal connection portion 101 is a disk-shaped disk structure, which is composed of a contact portion 110, an elastic portion 120, the pressing portion 130 and the indentation 140 forming a concentric circle as a whole.

The contact portion 110 corresponds to an outer surface shape of a battery cell terminal (not shown) having a circular structure, and comes into contact with the battery cell terminal at an outer circumferential surface thereof. The elastic part 120 is tapered with a predetermined inclination in the direction of the central axis to provide elastic force, and the pressing part 130 protrudes from the elastic part 120 in the direction of the central axis. An indentation portion 140 is formed in the center portion thereof, and a terminal portion 150 for connecting a protection circuit or the like to the side extension portion 152 of the connection member 100 is located.

The battery cells are elastically connected by the elastic part 120 having a predetermined inclination, and the cutout part 122 is formed on the elastic part 120 in a vortex shape with respect to the central axis, thereby reducing the elastic force of the elastic part 120. I can regulate it.

6 is a perspective view of a form in which the connection member according to an embodiment of the present invention is attached to two battery cells, and FIG. 7 is a partial plan view of a state in which the battery cells of FIG. 6 are mounted in a pack case. Is shown as an example.

Referring to these drawings, the connecting member 100 is arranged on the battery cell 200 with the pressing portion 130 facing outwards, and is electrically connected to the battery cell 200 through the contact portion 110. .

In this state, when the battery pack 200 is mounted on the pack case 300, or when the connection member 100 is additionally mounted while the battery cell 200 is mounted on the pack case 300, the side wall 310 of the pack case 300 and The structure in which the connection member 100 is positioned between the negative terminal of the battery cell 200 is made. Since the overall height of the connection member 100 in the non-mounted state is smaller than the width of the portion where the connection member 100 is inserted in the state in which the battery cell 200 is mounted in the pack case 300, the connection member 100 The pressing portion 130 of the) is pressed by the side wall 310, the elastic force is induced. Therefore, a close mechanical contact state is maintained between the battery cell 200 and the connection member 100, thereby making stable electrical connection.

8 and 9 schematically show an inversion prevention structure of the connection member according to the present invention with respect to external impact.

Referring to these drawings, the connection member 100 is positioned between the sidewall 310 of the case 300 and the battery cell 200, and the contact portion 110 is in contact with the electrode terminal of the battery cell 200 and is indented. The portion 140 is indented on the central axis with a depth smaller than the sum of the heights of the elastic portion and the pressing portion, and has a structure spaced apart from the electrode terminal of the battery cell 200 by a predetermined distance (a).

In such a structure, when the battery pack 200 presses the connection member 100 'in the direction of the arrow of FIG. 9 by application of an external force such as dropping or vibration, the indentation of the connection member 100' is a battery cell ( While contacting with the electrode terminal of the 200, it is supported between the case side wall 310 and the battery cell 200. Therefore, the case side wall 310 and the battery cell 200 are spaced apart by a predetermined distance a 'by the depth of the indentation 140 even during an external impact, thereby preventing the connection member 100' from being reversed. Can be.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

As described above, according to the present invention, since the welding, soldering process, etc. are not required for the electrical connection of the battery cell electrode terminals, it is possible to prevent a short circuit of the battery which may occur during the welding process and greatly reduce the defective rate. The stable coupling structure between the electrode terminals of the secondary battery cell can minimize the resistance change of the connection portion, and has an effect of greatly improving the production efficiency.

Claims (15)

When mounting two or more secondary battery cells in the battery pack, a connecting member for electrically connecting two or more battery cells arranged in the lateral direction by a physical contact method, (a) a contact portion corresponding to the outer surface shape of the battery cell terminal, the contact portion being in contact with the battery cell terminal at a predetermined width in the vicinity of the outer peripheral surface thereof; (b) an elastic portion tapered upward in a central axis direction with respect to the contact portion so as to provide a resilient traction force for the battery cell; (c) a pressing portion protruding at a predetermined height in the direction of the central axis with respect to the elastic portion for physical contact of the connecting member with respect to the battery cell; And (d) an indentation indented on a central axis to a depth smaller than the sum of the heights of the elastic portion and the pressing portion; Terminal connection parts having a configuration including a electrically connected corresponding to the number of battery cells of the side array, the connection member, characterized in that it comprises a circuit connection terminal portion on one side. The connecting member according to claim 1, wherein the connecting member is manufactured as a single body by pressing and deforming one conductive plate. The connecting member according to claim 1, wherein the battery cell is a cylindrical battery cell, and the contact part, the elastic part, the pressing part, and the indentation part have a concentric circular structure as a whole. 4. The connecting member according to claim 3, wherein the contact width of the contact portion with respect to the battery cell is 5 to 20% in size based on the radius of the terminal connecting portion. 4. The connecting member according to claim 3, wherein the elastic portion has a width of 20 to 60% based on a radius of the terminal connecting portion. The connecting member according to claim 1, wherein the elastic portion is tapered at an inclination of 5 to 30 degrees. The connecting member according to claim 1, wherein the pressing portion has a height of 30 to 60% based on the total height of the connecting member. The connecting member according to claim 1, wherein the indentation has a depth of 30 to 90% based on the total height of the connecting member. 2. The connecting member according to claim 1, wherein the elastic portion has two or more cutout portions having a predetermined width in a central axis direction, and they have a symmetrical structure with respect to the central axis. The connecting member according to claim 9, wherein the cutout portion is formed in a spiral shape with respect to a central axis. The connecting member according to claim 1, wherein at least one side of the connecting member is formed with a side extension part at which the terminal is located. A battery pack for a notebook computer having a structure in which a plurality of cylindrical battery cells are arranged to form an electrical connection and embedded in a pack case. The battery pack is provided to prevent electrical connection of battery cells (banks) arranged in a lateral direction. Battery pack characterized in that the connection member according to claim 1 is used. The battery pack as claimed in claim 12, wherein the connection member is used to connect the negative terminals of the bank to the negative circuit of the pack case. The battery pack as claimed in claim 13, wherein the connection member is made of a material selected from the group consisting of nickel, brass, aluminum, copper, and an optional alloy thereof. A notebook computer comprising the battery pack according to claim 12 as a power source.

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