KR102566309B1 - Secondary Battery - Google Patents

Abstract

The present invention relates to a secondary battery, and a technical problem to be solved is to reduce internal resistance and prevent an increase in contact resistance due to an external impact, thereby extending life and improving safety.
To this end, the present invention is electrically connected to a cap plate, a battery cell having an electrode terminal penetrating the cap plate, a connection tab electrically connected to one side of the cap plate so as to be spaced apart from the electrode terminal, and a connection tab, It includes a circuit board spaced apart from the cap plate in an upward direction, and the connection tab includes a first region in close contact with the upper surface of the cap plate, a second region connected to the lower surface of one side of the circuit board, and a gap between the first region and the second region. Disclosed is a secondary battery including a connection region connecting the first region and positioned inside so that the first region is adjacent to an electrode terminal compared to one end of the circuit board.

Description

Secondary Battery {Secondary Battery}

The present invention relates to a secondary battery.

A secondary battery is a battery that repeatedly performs charging and discharging unlike a primary battery. Small-capacity secondary batteries are used in small portable electronic devices such as mobile phones, notebook computers, and camcorders, and large-capacity secondary batteries can be used as power sources for driving motors of hybrid and electric vehicles.

For example, a secondary battery includes an electrode assembly for charging and discharging, a case for accommodating the electrode assembly, a cap plate coupled to an opening of the case, and electrode terminals for drawing the electrode assembly out of the cap plate. In addition, the electrode terminal of the secondary battery is connected to an external circuit to charge and discharge, and is connected to a protection circuit board to be connected to a protection element such as a positive temperature element.

SUMMARY OF THE INVENTION The present invention has been made to overcome the above-mentioned conventional problems, and an object of the present invention is to provide a secondary battery capable of reducing internal resistance and preventing an increase in contact resistance due to external impact.

A secondary battery according to the present invention includes a cap plate, a battery cell having electrode terminals penetrating the cap plate, a connection tab electrically connected to one side of the cap plate so as to be spaced apart from the electrode terminal, and the connection tab. and a circuit board electrically connected to and spaced apart from the cap plate in an upward direction, wherein the connection tab has a first region closely adhered to the upper surface of the cap plate and a second region connected to a lower surface of one side of the circuit board. and a connection area connecting the first area and the second area, and the first area may be located inside so as to be adjacent to the electrode terminal compared to one end of the circuit board.

An external terminal electrically connected to an upper surface of one side of the circuit board may be further included.

The second region may be located on an inner side adjacent to the electrode terminal compared to the external terminal so as not to overlap the external terminal on a plane.

An elastic pad interposed between the first area and the lower surface of the circuit board may be further included, and the first area may be pressed toward the cap plate by the elastic pad and brought into close contact with the cap plate.

Since the elastic pad has a length greater than that of the first region, the elastic pad may adhere to the upper surface of the cap plate.

The first region and the second region extend in opposite directions from the connection region and are horizontal to each other, and the connection region may be bent from the first region and the second region, respectively.

An upper case coupled to the cap plate to surround the circuit board and having coupling holes formed on both sides in a longitudinal direction and coupling members penetrating the coupling holes, wherein the coupling members extend through the coupling holes of the upper case. It can be penetrated and coupled to coupling grooves formed on upper surfaces of one side and the other side of the cap plate.

A plurality of projections protruding downward may be formed on a lower surface of the first region.

In addition, a secondary battery according to the present invention includes a cap plate, a battery cell having an electrode terminal penetrating the cap plate, a connection tab electrically connected to one side of the cap plate so as to be spaced apart from the electrode terminal, and the connection tab. A circuit board electrically connected to the tab and spaced apart from the cap plate in an upward direction, wherein the connection tab has a first area closely adhered to the upper surface of the cap plate and a second area connected to a lower surface of one side of the circuit board. region, and a connection region connecting the first region and the second region, and further comprising an elastic pad interposed between the first region and the lower surface of the circuit board, wherein the first region comprises the elastic pad. The cap plate may be pressed in the direction of the cap plate by the pad so as to be brought into close contact with the cap plate.

An upper case coupled to the cap plate to surround the circuit board and having coupling holes formed on both sides in a longitudinal direction and coupling members penetrating the coupling holes, wherein the coupling members extend through the coupling holes of the upper case. It can be penetrated and coupled to coupling grooves formed on upper surfaces of one side and the other side of the cap plate.

The first region may extend to one end of the cap plate, and a coupling hole corresponding to the coupling groove may be formed.

The coupling member may pass through the coupling hole of the upper case and the coupling hole of the first region, and be coupled to the coupling groove of the cap plate.

The secondary battery according to the present invention can reduce internal resistance and prevent an increase in contact resistance due to external impact.

1A to 1C are a perspective view, an exploded perspective view, and a cross-sectional view of a secondary battery according to an embodiment of the present invention.
FIG. 2 is an enlarged bottom perspective view of a connection tab in the secondary battery shown in FIGS. 1A to 1C .
3A to 3B are exploded perspective views and cross-sectional views of a secondary battery according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art, and the following examples may be modified in many different forms, and the scope of the present invention is as follows It is not limited to the examples. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the spirit of the invention to those skilled in the art.

In addition, in the following drawings, the thickness or size of each layer is exaggerated for convenience and clarity of explanation, and the same reference numerals refer to the same elements in the drawings. As used herein, the term "and/or" includes any one and all combinations of one or more of the listed items. In addition, the meaning of "connected" in the present specification means not only when member A and member B are directly connected, but also when member A and member B are indirectly connected by interposing member C between member A and member B. do.

Terms used in this specification are used to describe specific embodiments and are not intended to limit the present invention. As used herein, the singular form may include the plural form unless the context clearly indicates otherwise. Also, when used herein, "comprise" and/or "comprising" specifies the presence of the recited shapes, numbers, steps, operations, elements, elements, and/or groups thereof. and does not exclude the presence or addition of one or more other shapes, numbers, operations, elements, elements and/or groups.

In this specification, terms such as first and second are used to describe various members, components, regions, layers and/or portions, but these members, components, regions, layers and/or portions are limited by these terms. It is self-evident that These terms are only used to distinguish one element, component, region, layer or section from another region, layer or section. Accordingly, a first member, component, region, layer or section described in detail below may refer to a second member, component, region, layer or section without departing from the teachings of the present invention.

Space-related terms such as “beneath,” “below,” “lower,” “above,” and “upper” are associated with an element or feature shown in a drawing. Used for easy understanding of other elements or features. Terminology related to this space is for easy understanding of the present invention according to various process states or use states of the semiconductor device, and is not intended to limit the present invention. For example, if the semiconductor device in the figure is turned over, elements described as “lower” or “below” become “upper” or “above”. Thus "below" encompasses "above" or "under".

Referring to FIG. 1A, a perspective view of a secondary battery according to an embodiment of the present invention is shown. Referring to FIG. 1B, an exploded perspective view of the secondary battery of FIG. 1A is shown. Referring to FIG. 1C, the secondary battery of FIG. 1 is shown. A partial cross-sectional view taken along line 1c-1c of is shown.

As shown in FIGS. 1A to 1C, the secondary battery 100 includes a battery cell 110, a protection circuit module 120 electrically connected to the battery cell 110, and a battery cell 110 and a protection circuit module. Includes a connection tab 130 electrically connecting between 120 and a protective circuit module 120 coupled to the upper portion of the battery cell 110 and an upper case 150 mounted to cover the connection tab 130 do. In addition, the secondary battery 100 includes an elastic pad 140 interposed between the protection circuit module 120 and the connection tab 130, a lower case 160 covering the lower surface of the battery cell 110, and a battery cell 110 ) May further include a label 170 covering the side of the.

The battery cell 110 includes an electrode assembly (not shown) composed of a positive electrode, a negative electrode, and a separator interposed between the positive electrode and the negative electrode to supply electric energy therein. In addition, the battery cell 110 may include a case 111 accommodating the electrode assembly and an electrolyte solution (not shown) and a cap plate 112 sealing an opening of the case 111 . In addition, the battery cell 110 further includes an electrode terminal 113 protruding upward from the cap plate 112 .

The cap plate 112 has a flat plate shape, and an upper surface opposite to the surface facing the case 111 is exposed to the outside. The cap plate 112 may further include coupling grooves 112a provided at both ends in the longitudinal direction (x). The coupling groove 112a is provided to insert and couple the coupling member 151 when the upper case 150 and the battery cell 110 are coupled.

The case 111 and the cap plate 112 may be electrically connected to the positive electrode of the electrode assembly, and the electrode terminal 113 may be electrically connected to the negative electrode of the electrode assembly. However, the case 111 and the cap plate 112 may serve as a negative electrode and the electrode terminal 113 may serve as an anode according to the selection of a person skilled in the art.

The electrode terminal 113 protrudes substantially from the center of the cap plate 112 and is electrically insulated from the cap plate 112 . A gasket 114 may be further provided between the electrode terminal 113 and the cap plate 112 . The gasket 114 is electrically made of an insulating material and electrically separates the electrode terminal 113 and the cap plate 112 from each other. In addition, the gasket 114 may prevent the electrolyte contained in the case 111 and the cap plate 112 from leaking to the outside.

The protection circuit module 120 includes a plate-shaped circuit board 121 disposed above the cap plate 113, a protection circuit unit 122 mounted on the circuit board 121, a negative electrode tab 123, and an external terminal. (124).

The circuit board 121 is a printed circuit board on which wiring patterns are printed, and has a plate shape extending in parallel to be spaced apart from the cap plate 112 . A plurality of protection circuit units 122 and external terminals 124 may be mounted on the upper surface of the circuit board 110 so as to be electrically connected through wiring patterns of the circuit board 110 . The protection circuit unit 122 and the external terminal 124 may be soldered to the circuit board 110, but the present invention is not limited thereto. The protection circuit unit 122 may selectively include passive elements such as resistors and capacitors, active elements such as field effect transistors, safety elements such as PTC elements, and integrated circuits. In addition, the protection circuit unit 124 blocks the charge/discharge path of the bare cell 110 in situations such as overheating or overcurrent of the battery cell 110 to prevent deterioration of life, overheating, and explosion of the bare cell 110. there is.

The lower surface of the circuit board 110 may face the upper surface of the cap plate 112 . In the circuit board 110, the negative electrode is electrically connected to the electrode terminal 113 of the battery cell 110 through the negative electrode tab 123, and the positive electrode is connected to the cap plate of the battery cell 110 through the connection tab 130. (112) and electrically connected. At this time, the PTC element 125 is electrically connected between the circuit board 110 and the electrode terminal 113, so that the electrical connection between the circuit board 120 and the electrode terminal 113 can be blocked in case of excessive temperature rise or overcurrent. there is.

The external terminal 124 may be mounted on one side 121a in the longitudinal direction (x) on the upper surface of the circuit board 121 . The external terminal 124 may be exposed to the outside through a terminal hole 152 provided in the upper case 150 . The external terminal 124 is an external input/output terminal for electrical connection with an external electronic device or charger. In addition, the external terminal 124 is electrically connected to the wiring pattern of the circuit board 110 and electrically connected to the battery cell 110 through the wiring pattern of the circuit board 121 . That is, the external terminal 124 is an input/output terminal for electrically connecting an external electronic device or charger and the battery cell 110 .

The connection tab 130 has a step difference between the first area 131 connected to the upper surface of the cap plate 112 and the second area 132 connected to the lower surface of the circuit board 121. A connection area 133 connecting between 131 and the second area 132 is included. The connection tab 130 may be made of nickel (Ni) or a nickel alloy. Also, the connection tab 130 electrically connects the cap plate 112 and the positive electrode of the circuit board 121 . In addition, the connection tab 130 may be spaced apart from the electrode terminal 113 in one side of the longitudinal direction (x). A portion of the connection tab 130 may be located below one side of the circuit board 121 on which the external terminal 124 is mounted. Also, the connection tab 130 may be electrically connected to the external terminal 124 through a wiring pattern of the circuit board 121 .

The first area 131 is formed to extend along the upper surface of the cap plate 112 . The first region 131 may come into contact with and come into close contact with the top surface of the cap plate 112 and may have the same polarity as that of the cap plate 112 . The upper surface of the first region 131 may come into contact with and come into close contact with the elastic pad 140 . That is, the elastic pad 140 interposed between the upper surface of the first region 131 and the lower surface of the circuit board 121 presses the first region 131 in the direction of the cap plate 112 to be brought into close contact therewith. there is. The first region 131 may be electrically connected to the cap plate 112 by being in close contact with the cap plate 112 by pressing the elastic pad 140 without separate physical deformation. The first region 131 may be located below one side of the circuit board 121 on which the external terminal 124 is mounted. That is, the first region 131 may be spaced outward from the electrode terminal 113 so as to be located below the external terminal 124 . Also, the first region 131 may be located inside compared to one end of the circuit board 121 . Here, the inner side means the center of the cap plate 112 where the electrode terminal 113 is located or the center of the circuit board 121 corresponding thereto. In addition, the outer side refers to one side and/or the other side of the cap plate 112 and the circuit board 121 in the longitudinal direction (x). As shown in FIG. 2 , the first region 131 may have a plurality of protrusions 131a on its lower surface. The plurality of protrusions 131a may have a sharp cone shape, and when the first area 131 is in close contact with the cap plate 112 by the elastic pad 140, they dig into the upper surface of the cap plate 112. can That is, the contact surface between the first region 131 and the cap plate 112 is increased by the plurality of protrusions 131a, so that contact resistance can be reduced.

The second region 132 may be fixed by physical deformation while in contact with the lower surface of the circuit board 121 . For example, the upper surface of the second region 132 may be fixed to the lower surface of the circuit board 121 by welding. The second region 132 may be welded to the lower surface of the circuit board 121 so as not to overlap with the external terminal 124 mounted on the circuit board 121 in plan view. The second region 132 may be located inside compared to one side of the circuit board 121 on which the external terminals 124 are mounted. The second region 132 is electrically connected to the wiring pattern of the circuit board 121 . The second region 132 may extend in an opposite direction to the first region 131 with the connection region 133 as the center.

a connection tab electrically connected to one side of the cap plate so as to be spaced apart from the electrode terminal; and

a circuit board electrically connected to the connection tab and spaced upward from the cap plate;

The connection tab includes a first area closely attached to an upper surface of the cap plate, a second area connected to a lower surface of one side of the circuit board, and a connection area connecting the first area and the second area;

The secondary battery according to claim 1 , wherein the second region is located on the inside so as to be adjacent to the electrode terminal compared to one end of the circuit board.

The connection area 133 connects the first area 131 and the second area 132 . The connection area 133 is provided to compensate for a step difference between the first area 131 and the second area 132 that are parallel to each other, and is bent from the first area 131 and the second area 132, respectively. It can be. That is, the first area 131 and the second area 132 may be horizontal to the cap plate 112 , and the connection area 133 may have a certain angle with the cap plate 112 . For example, the connection area 133 may be perpendicular to the cap plate 112 by bending portions connected to the first area 131 and the second area 132, but this is not limited in the present invention. The connection area 133 compensates for the distance between the circuit board 121 and the cap plate 112 . The length of the connection area 133 is preferably smaller than the height of the elastic pad 140 . Here, the height of the elastic pad 140 means the distance from the surface of the elastic pad 140 facing the upper surface of the cap plate 112 to the opposite surface of the elastic pad 140 to the surface facing the lower surface of the circuit board 121 . That is, the height of the elastic pad 140 means the thickness in the height direction (y). Since the connection tab 130 has a smaller internal resistance than the plurality of fine wiring patterns provided on the circuit board 121 and can be connected to the cap plate 112 without separate physical deformation, the connection tab 130 It can be easily changed in size and position.

The elastic pad 140 has a plate shape and is interposed between the first region 131 of the connection tab 130 contacting the cap plate 112 and the circuit board 121 . The elastic pad 140 may have a size that covers the entire first region 131 . That is, the size of the elastic pad 140 may be greater than or equal to the size of the first area 131 of the connection tab 130 . When the elastic pad 140 is larger than the first area 131, the elastic pad 140 adheres closely to cover the entire top surface of the first area 131, and partially covers the top surface of the cap plate 112. can be adhered to. The elastic pad 140 has a height 140h greater than the length 133h of the connection area 133 of the connection tab 130 . Accordingly, when the upper case 150 is coupled to the cap plate 112, the elastic pad 140 may be compressed in the height direction (y) of the secondary battery 100. That is, the elastic pad 140 provides an elastic force that pushes the upper surface of the first region 131 and the upper surface of the cap plate 112 toward the battery cell 110 and pushes the circuit board 121 upward. The first region 131 of the connection tab 130 can be electrically connected to the top of the cap plate 112 by being in close contact with the elastic pad 140 without any physical deformation. In addition, the coupling force between the cap plate 112 and the first region 131 of the connection tab 130 may be improved by the elastic force of the elastic pad 140 . In addition, since the elastic pad 140 can also absorb shock applied from the outside, an increase in contact resistance between the connection tab 130 and the cap plate 112 can be prevented. The elastic pad 140 may be formed of any one of silicone, rubber, or porous foam tape.

In addition, the elastic pads 140 may be located inside compared to both ends of the upper case 150 so as not to overlap with the coupling member 151 coupled to both sides in the longitudinal direction of the upper case 150 on a plane. The elastic pad 140 may further include an auxiliary elastic pad 140a additionally provided on a lower portion of one side in the longitudinal direction (x) of the circuit board 121 on which the external terminal 124 is formed, as well as a lower portion of the other side.

The upper case 150 may surround the protection circuit module 120 and may be fixed to an upper surface of the cap plate 112 . Seating grooves 150a are provided on both sides of the upper case 150 in the longitudinal direction, respectively. Also, in each seating groove 150a, a coupling hole 150b passing through the center of the seating groove 150a is formed. A coupling member 151 may pass through the coupling hole 150b of the upper case 150 . The coupling member 151 may be a bolt. In the coupling member 151, the body portion 151b may pass through the coupling hole 150b and be coupled to the coupling groove 112a of the cap plate 112. The head portion 151a of the coupling member 151 may be in close contact with the seating groove 150a. In this way, the upper case 150 may be fixed to the cap plate 112 of the battery cell 110 through coupling members 151 respectively coupled to both sides in the longitudinal direction. At this time, the circuit board 121 may be located inside the upper case 150, and the elastic pad 140 is compressed in the height direction (y) so that the upper surface of the first region 131 and the cap plate 112 are formed. An elastic force may be provided to push the upper surface of the battery cell 110 toward the battery cell 110 and push the circuit board 121 toward the upper case 150 .

The upper case 150 is an insulation case formed by injection molding of an insulating material, and can protect the protection circuit module 120 from an external environment and impact. In addition, the upper case 150 may be provided with a terminal hole 150c to expose the external terminal 124 mounted on the circuit board 121 to the outside. That is, the terminal hole 150c of the upper case 150 may be provided on one side of the longitudinal direction (x) where the external terminal 124 is provided.

In addition, the upper case 150 may additionally be provided with a plurality of ribs 152 on the inner side in the height direction (y). The plurality of ribs 152 of the upper case 150 may support and press the upper surface of the circuit board 121 in the direction of the cap plate 112 to compress the elastic pad 140 . That is, when the upper case 150 is coupled to the battery cell 110, the cap plate 112 and the circuit board 121 of the battery cell 110 are separated by the elastic force generated by the compression of the elastic pad 140. The connection tabs 130 may be in close contact with each other to increase contact force and bonding force.

The lower case 160 covers the lower surface of the battery cell 110 to prevent the battery cell 110 from being damaged by an external impact. A double-sided adhesive tape 161 may be interposed between the lower case 160 and the lower surface of the battery cell 110 to bond and bond the lower case 160 and the battery cell 110 together.

The label 170 surrounds the battery cell 110 , the upper case 150 and the lower case 160 . The label 170 may be attached to the battery cell 110 , the upper case 150 and the lower case 160 by an adhesive. Also, information such as the capacity and product number of the battery pack 100 may be printed on the outer surface of the label 170 . The label 170 couples the upper case 150 and the lower case 160 to the battery cell 110 to prevent the upper case 150 and the lower case 160 from moving.

Referring to FIG. 3A , an exploded perspective view of a secondary battery according to another embodiment of the present invention is shown, and referring to FIG. 3B , a partial cross-sectional view of the secondary battery is shown. A perspective view of the secondary battery 200 may be the same as that of the secondary battery 100 shown in FIG. 1A.

3A to 3B, the secondary battery 200 includes a battery cell 110, a protection circuit module 120 electrically connected to the battery cell 110, a battery cell 110, and a protection circuit module. Includes a connection tab 230 electrically connecting between 120 and a protective circuit module 120 coupled to the top of the battery cell 110 and an upper case 150 mounted to cover the connection tab 230 do. In addition, the secondary battery 200 includes an elastic pad 240 interposed between the protection circuit module 120 and the connection tab 230, a lower case 160 covering the lower surface of the battery cell 110, and the battery cell 110 ) May further include a label 170 covering the side of the.

The battery cell 110, the protection circuit module 120, the upper case 150, the lower case 160, and the label 170 of the secondary battery 200 are the secondary battery 100 shown in FIGS. 1A to 1C. is the same as Therefore, hereinafter, the structure of the connection tab 230 and the elastic pad 240, which are different from those of the secondary battery 100, in the secondary battery 200 will be mainly described with reference to FIGS. 3A and 3B.

The connection tab 230 has a step difference between the first area 231 connected to the upper surface of the cap plate 112 and the second area 232 connected to the lower surface of the circuit board 121. A connection area 233 connecting between 231 and the second area 232 is included. The connection tab 230 may be made of nickel (Ni) or a nickel alloy. Also, the connection tab 230 electrically connects the cap plate 112 and the positive electrode of the circuit board 121 . In addition, the connection tab 230 may be spaced apart from the electrode terminal 113 in one side of the longitudinal direction (x). A portion of the connection tab 230 may be located below one side of the circuit board 121 on which the external terminal 124 is mounted. Also, the connection tab 230 may be electrically connected to the external terminal 124 through a wiring pattern of the circuit board 121 .

The first region 231 is formed to extend to one end along the upper surface of the cap plate 112 . In addition, a coupling hole 231a corresponding to the coupling groove 112a of the cap plate 112 is formed on one side of the first region 231 opposite to the other side connected to the connection region 233 . The coupling member 151 may pass through the coupling hole 231a formed in the first region 231 . That is, the coupling member 151 penetrating the coupling hole 150b of the upper case 150 also penetrates the coupling hole 231a of the first region 231 and attaches to the coupling groove 112a of the cap plate 112. can be combined One side of the first region 231 may be coupled to the cap plate 112 by the coupling member 151 and may have the same polarity as the cap plate 112 . In addition, the first area 231 may contact and adhere closely to the upper surface of the cap plate 112 by the elastic pad 240 . That is, by the elastic pad 240 interposed between the upper surface of the first area 231 and the lower surface of the circuit board 121, the first area 231 may be pressed in the direction of the cap plate 112 and brought into close contact therewith. there is. The first region 231 may be located below one side of the circuit board 121 on which the external terminal 124 is mounted. That is, the first region 231 may be spaced outward from the electrode terminal 113 so as to be located below the external terminal 124 . Like the connection tab 130 shown in FIG. 2, the first area 231 is further provided with a plurality of protrusions on the lower surface to increase the bonding surface between the first area 231 and the cap plate 112. Contact resistance can be reduced.

The second region 232 may be fixed by physical deformation while in contact with the lower surface of the circuit board 121 . For example, the upper surface of the second region 232 may be fixed to the lower surface of the circuit board 121 by welding. The second region 232 may be welded to the lower surface of the circuit board 121 so as not to overlap the external terminal 124 in plan view. The second region 232 may be located inside compared to one side of the circuit board 121 on which the external terminals 124 are mounted. Here, the inner side means the center of the cap plate 112 where the electrode terminal 113 is located or the center of the circuit board 121 corresponding thereto. The second region 232 is electrically connected to the wiring pattern of the circuit board 121 . The second region 232 may extend in the opposite direction to the first region 231 with the connection region 233 as the center. The second region 232 is welded to the circuit board 121 and electrically connected to the wiring pattern of the circuit board 121 .

The connection area 233 connects the first area 231 and the second area 232 . The connection area 233 is provided to compensate for the step difference between the first area 231 and the second area 232 that are parallel to each other, and is bent from the first area 231 and the second area 232, respectively. It can be. That is, the first area 231 and the second area 232 may be horizontal to the cap plate 112 , and the connection area 233 may have a certain angle with the cap plate 112 . For example, the connection area 233 may be perpendicular to the cap plate 112 by bending portions connected to the first area 231 and the second area 232, but this is not limited in the present invention. The connection area 233 compensates for the distance between the circuit board 121 and the cap plate 112 . The length of the connection area 233 is preferably smaller than the height of the elastic pad 240 . Here, the height of the elastic pad 240 means the distance from the surface of the elastic pad 240 facing the upper surface of the cap plate 112 to the opposite surface of the elastic pad 240 to the surface facing the lower surface of the circuit board 121 . That is, the height of the elastic pad 240 means the thickness in the height direction (y).

The elastic pad 240 has a plate shape and is interposed between the first region 231 of the connection tab 230 contacting the cap plate 112 and the circuit board 121 . The elastic pad 240 may have a length 240b in the longitudinal direction (x) covering a portion of the first region 231 . That is, the elastic pad 240 may have a length 240b smaller than the first area 231 of the connection tab 230 . The elastic pad 140 is interposed between the circuit board 121 and the first area 231 to cover the first area 231, and exposes one side where the coupling hole 231a is formed to the outside. The elastic pad 240 has a height 240h greater than the length 233h of the connection area 233 of the connection tab 230 . Accordingly, when the upper case 150 is coupled to the cap plate 112, the elastic pad 240 may be compressed in the height direction (y) of the secondary battery 100. That is, the elastic pad 240 provides an elastic force that pushes the upper surface of the first region 231 and the upper surface of the cap plate 112 toward the battery cell 110 and pushes the circuit board 121 upward. The first region 231 of the connection tab 230 can be electrically connected to the top of the cap plate 112 by being in close contact with the upper portion of the cap plate 112 without separate physical deformation by the elastic pad 240 . In addition, the coupling force between the cap plate 112 and the first area 231 of the connection tab 230 may be improved by the elastic force of the elastic pad 240 . In addition, the elastic pad 240 can absorb shock applied from the outside, and can prevent an increase in contact resistance between the connection tab 230 and the cap plate 112 . The elastic pad 240 may be formed of any one of silicone, rubber, or porous foam tape.

In addition, the elastic pads 240 may be located inside compared to both ends of the upper case 150 so as not to overlap with the coupling member 151 coupled to both sides in the longitudinal direction of the upper case 150 on a plane. The elastic pad 240 may further include an auxiliary elastic pad 240a further provided on a lower portion of one side in the longitudinal direction (x) of the circuit board 121 on which the external terminal 124 is formed, as well as an additional lower portion of the other side.

What has been described above is only one embodiment for carrying out the secondary battery according to the present invention, and the present invention is not limited to the above-described embodiments, and goes beyond the scope of the present invention as claimed in the following claims. Without this, anyone skilled in the art to which the present invention belongs will say that the technical spirit of the present invention exists to the extent that various changes can be made.

100, 200; secondary battery
110; battery cell 120; protection circuit module
130; connection tab 140; elastic pad
150; upper case 160; lower case
170; label

Claims (12)

a battery cell having a cap plate and an electrode terminal penetrating the cap plate;
a connection tab electrically connected to one side of the cap plate so as to be spaced apart from the electrode terminal; and
a circuit board electrically connected to the connection tab and spaced upward from the cap plate;
The connection tab includes a first area closely attached to an upper surface of the cap plate, a second area connected to a lower surface of one side of the circuit board, and a connection area connecting the first area and the second area;
The first region is located on the inside so as to be adjacent to the electrode terminal compared to one end of the circuit board,
A secondary battery characterized in that a plurality of protrusions protruding downward are formed on the lower surface of the first region. The method of claim 1,
The secondary battery further comprising an external terminal electrically connected to an upper surface of one side of the circuit board. The method of claim 2,
The secondary battery according to claim 1 , wherein the second region is located on an inner side adjacent to the electrode terminal compared to the external terminal so as not to overlap the external terminal on a plane. The method of claim 1,
Further comprising an elastic pad interposed between the first region and the lower surface of the circuit board,
The secondary battery of claim 1 , wherein the first region is pressed in a direction of the cap plate by the elastic pad and brought into close contact with the first region. The method of claim 4,
The secondary battery of claim 1 , wherein the elastic pad has a length greater than that of the first region and adheres to the upper surface of the cap plate. The method of claim 1,
The secondary battery of claim 1 , wherein the first region and the second region extend in opposite directions from the connection region and are horizontal to each other, and the connection region is bent from the first region and the second region, respectively. The method of claim 1,
coupled to the cap plate to surround the circuit board;
Further comprising an upper case having coupling holes formed on both sides in the longitudinal direction and coupling members penetrating the coupling holes,
The secondary battery of claim 1 , wherein the coupling member is coupled to coupling grooves formed on upper surfaces of one side and the other side of the cap plate through coupling holes of the upper case. delete a battery cell having a cap plate and an electrode terminal penetrating the cap plate;
a connection tab electrically connected to one side of the cap plate so as to be spaced apart from the electrode terminal; and
a circuit board electrically connected to the connection tab and spaced upward from the cap plate;
The connection tab includes a first area closely attached to an upper surface of the cap plate, a second area connected to a lower surface of one side of the circuit board, and a connection area connecting the first area and the second area;
The secondary battery of claim 1, further comprising an elastic pad interposed between the first area and the lower surface of the circuit board, wherein the first area is pressed in a direction of the cap plate by the elastic pad and brought into close contact with the cap plate. The method of claim 9,
coupled to the cap plate to surround the circuit board;
Further comprising an upper case having coupling holes formed on both sides in the longitudinal direction and coupling members penetrating the coupling holes,
The secondary battery of claim 1 , wherein the coupling member is coupled to coupling grooves formed on upper surfaces of one side and the other side of the cap plate through coupling holes of the upper case. The method of claim 10,
The secondary battery of claim 1 , wherein the first region extends to one end of the cap plate and has a coupling hole corresponding to the coupling groove. The method of claim 11,
The secondary battery of claim 1 , wherein the coupling member penetrates the coupling hole of the upper case and the coupling hole of the first region, and is coupled to the coupling groove of the cap plate.

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