KR20090090546A - Protection circuit board and battery pack having the same - Google Patents

Abstract

A protection circuit board is provided to minimize the mounted area of each mounting assembly, to prevent the thickness of the protection circuit board from being increased, and to improve safety and reliability of the battery pack. A protection circuit board(100) comprises a mounting assembly(120) including one or a plurality of lead pins(125), and a mounting substrate(110) formed with one or a plurality of through holes(115) or connection holes corresponding to the lead pins. The end of the lead pin is positioned at the inner side of the pe through holes or connection holes.

Description

Protection circuit board and battery pack having the same {Protection Circuit Board and Battery Pack having the same}

The present invention relates to a protective circuit board and a battery pack having the same, reducing the mounting area of each of the mounting components mounted on the protective circuit board, and prevents the substantial thickness of the protective circuit board from increasing by the mounting process, By preventing an electrical short circuit between the mounting board and the mounting component of the protective circuit board by an external impact, etc., to minimize the thickness of the battery pack, and to improve the safety and reliability of the battery pack and a battery having the same It's about the pack.

Recently, compact and lightweight portable electronic / electric devices such as cellular phones, notebook computers, camcorders, and the like have been actively developed and produced, and the portable electronic / electric devices can be operated even in places where no separate power source is provided. The pack is built. The battery pack is represented by a nickel-cadmium (Ni-Cd) battery, a nickel-hydrogen (Ni-MH) battery and a lithium (Li) battery in consideration of economical aspects, and a rechargeable battery capable of charging and discharging is generally used. .

Among these, the lithium secondary battery is widely used in the battery pack of the portable electronic / electrical device because the operation voltage is about three times higher and the energy density per unit weight is higher than that of the nickel-cadmium battery or the nickel-hydrogen battery. The lithium secondary battery is classified into a lithium ion battery using a liquid electrolyte and a lithium polymer battery using a polymer electrolyte according to the type of electrolyte used, or divided into a rectangular, cylindrical, and pouch type according to the manufactured shape.

In general, a battery pack using a lithium secondary battery includes a bare cell including an electrode assembly, a can containing an electrolyte for allowing lithium ions to move between the electrode assembly and the electrode assembly, and a cap assembly for sealing the can; And a protection circuit board electrically connected to the bare cell to control charge and discharge of the bare cell.

The electrode assembly may include a positive electrode plate including a positive electrode current collector coated with a positive electrode active material and a positive electrode tab electrically connected to one side of the positive electrode current collector, a negative electrode current collector coated with a negative electrode active material, and one side of the negative electrode current collector. It includes a negative electrode plate including a negative electrode tab connected to the separator and a separator located between the positive electrode plate and the negative electrode plate.

The electrolyte is a non-aqueous organic electrolyte that is a mixture of lithium salts and high-purity organic solvents, and plays a role of allowing the lithium ions generated by the electrochemical reaction in the positive electrode plate and the negative electrode plate of the electrode assembly during charge and discharge, or a polymer It may be a polymer using an electrolyte.

The protection circuit board is electrically connected to the bare cell to control voltage or current during charging and discharging of the bare cell, thereby preventing the bare cell from being overcharged or overdischarged. It provides a mounting component such as a protective element or connector for controlling and a space in which the mounting component can be mounted, and a mounting substrate having a conductive pattern for electrical connection between the mounting component on one or both surfaces thereof.

In order to mount a component such as a protective element or a connector on a mounting board of the protective circuit board, a surface mounting method (SMT) or a pin-insertion type (PI-type) is generally used.

However, in the surface mounting method SMT, a conductive pattern is formed on a surface of the mounting substrate on which the mounting component is located, the lead pin of the mounting component is brought into contact with one side of the conductive pattern, and then the lead pin is conductive. The pattern is electrically connected by a connection method such as soldering using a connecting member such as a brazing material, and the conductive pattern and the lead pin are connected using a space for contact between the conductive pattern and the lead pin and a connecting member such as the brazing material. Since a space for electrically connecting is required, the mounting area of each mounting component is increased, so that a relatively small number of mounting components are mounted on a mounting board having the same area.

In addition, the insertion type (PI-type) is a hole in the mounting substrate, the lead pin of the mounting component located on one side of the mounting substrate is inserted into the hole, and then through the hole and the lead pin The conductive pattern formed on the other side of the mounting substrate is electrically connected by using a connecting member such as a brazing material, so that the lead pin may be electrically connected to the lead pin passing through the hole and the conductive pattern. Protruding by a certain length in the other direction, the protruding lead pin is wrapped with the connecting member, the substantial thickness of the protective circuit board increases, the operability is reduced due to the gap between the mounting component and the conductive pattern There is a problem.

In addition, in the surface mount method SMT and the insert-mount method PI-type, a connecting member such as a solder material that electrically connects the conductive pattern of the mounting substrate and the lead pin of the mounting component is exposed to the outside. The connection member may be separated from the mounting substrate by an impact, and thus, the electrical connection between the conductive pattern and the lead pin may be interrupted, or an unwanted electrical connection may be made, causing a malfunction of the protective circuit board. There is this.

Therefore, the present invention is to solve the problems of the prior art as described above, by changing the mounting structure of the mounting component of the protective circuit board and the electrical connection structure between the mounting component and the mounting board, thereby reducing the mounting area of each mounting component. It is an object of the present invention to provide a protective circuit board and a battery pack having the same, which can minimize and prevent the substantial thickness of the protective circuit board from being increased by a mounting process.

The object of the present invention is a mounting component including one or more lead pins; And a mounting substrate having one or more through holes or connection grooves corresponding to the lead pins, wherein the ends of the lead pins are located inside the through holes or connection grooves. Is achieved by

In addition, the object of the present invention is a bare cell; And a protective circuit board electrically connected to the bare cell and including a mounting component including one or more lead pins and a mounting substrate having one or more through holes or connection grooves corresponding to the lead pins. And, the end of the lead pin is achieved by a battery pack, characterized in that located in the through hole or the connecting groove.

The protective circuit board and the battery pack having the same according to the present invention form a through hole or a connection groove corresponding to the lead pin of the mounting component in the mounting board of the protection circuit board, and the end of the lead pin is connected to the through hole or the connection groove. Since the mounting area of each mounting component is minimized so that a large number of protection elements or connectors can be mounted on the protection circuit board of the same area, the stability of the battery pack can be improved.

In addition, the through hole or the connection groove is filled with a connection member such as a brazing filler material so that the conductive pattern of the lead pin and the mounting substrate is electrically connected through the inside of the through hole or the connection groove, thereby protecting the circuit board by a mounting process. The thickness of the battery pack is minimized by preventing a substantial increase in the thickness of the circuit board and preventing a malfunction of the protection circuit board by changing the electrical connection structure between the lead pin and the conductive pattern due to an external impact. Has the effect of improving.

Details of the above objects and technical configurations and effects according to the present invention will be more clearly understood by the following detailed description with reference to the drawings showing preferred embodiments of the present invention. In addition, throughout the specification, the same reference numbers refer to the same components, and when a portion is said to be "connected" with another portion, it is not only "directly connected" but also with other elements in between. It also includes the case of "electrically connecting". In addition, in the drawings, the length, thickness, etc. of the layers and regions may be exaggerated for convenience.

(First embodiment)

1 is an exploded perspective view illustrating a battery pack according to a first embodiment of the present invention, and FIG. 2A is a cross-sectional view illustrating a protection circuit board of the battery pack according to the first embodiment of the present invention.

1 and 2A, a battery pack according to a first embodiment of the present invention includes a bare cell 40 and a protective circuit board 100 electrically connected to the bare cell 40. The bare cell 40 may seal the can 20 and the can 20 to accommodate an electrolyte (not shown) to allow lithium ions to move between the electrode assembly 10 and the electrode assembly 10. Cap assembly 30. Here, in FIG. 1 of the present invention, although the bare cell 40 shows a battery pack that is a rectangular lithium secondary battery, the bare cell 40 may be cylindrical or pouch type.

The electrode assembly 10 includes a positive electrode plate 12 including a positive electrode current collector (not shown) coated with a positive electrode active material (not shown) and a positive electrode tab 15 electrically connected to one side of the positive electrode current collector, and a negative electrode active material ( A negative electrode plate 11 including a negative electrode current collector (not shown) coated with a negative electrode and a negative electrode tab 14 electrically connected to one side of the negative electrode current collector, and positioned between the positive electrode plate 12 and the negative electrode plate 11. The separator 13 is included. Here, in FIG. 1, the negative electrode tab 14 is positioned at the center of the electrode assembly 10, and the positive electrode tab 15 is positioned at an edge of the electrode assembly 10. Positions of the negative electrode tab 14 and the positive electrode tab 15 may be changed, and either the negative electrode tab 14 or the positive electrode tab 15 may protrude in a direction opposite to the cap assembly 30.

The positive electrode active material is LiCoO ₂ , LiNiO ₂ , LiMnO ₂ , LiMn ₂ O ₄ or LiNi _{1- xy} Co _x M _y O ₂ (where 0 ≦ x ≦ 1, 0 ≦ y ≦ 1, 0 ≦ x + y ≦ 1 , M may be any of a lithium-containing transition metal oxide or a lithium chalcogenide compound represented by a metal oxide, such as metals such as Al, Sr, Mg, La, etc., the negative electrode active material is crystalline carbon, amorphous carbon, carbon composite , Carbon material such as carbon fiber, lithium metal or lithium alloy.

The positive electrode current collector and the negative electrode current collector may be formed of one selected from the group consisting of stainless steel, nickel, copper, aluminum, and alloys thereof. Preferably, the positive electrode current collector is formed of aluminum or an aluminum alloy, and the negative electrode current collector Is formed of copper or copper alloy to maximize efficiency.

The separator 13 is positioned between the positive electrode plate 12 and the negative electrode plate 11 to prevent an electrical short circuit and to allow movement of lithium ions. The separator 13 may be formed of a polyolefin-based polymer film such as polyethylene (PE) or polypropylene (PP) or multiple films thereof.

As shown in the drawing, the can 20 may be formed of a metal material having an open upper end, and may be formed in a cylindrical or pouch type. The can 20 is formed of a light and ductile metal such as aluminum, aluminum alloy, or stainless steel, such that the positive electrode tab 15 or the negative electrode tab 14 is electrically connected to the can 20. It is desirable to allow 20 to serve as a terminal.

The cap assembly 30 coupled to the opened upper portion of the can 20 includes a cap plate 35, an insulating plate 34, a terminal plate 33, an insulating case 32, and an electrode terminal 31. . The cap plate 35 is a metal plate having a size and shape corresponding to the top opening of the can 20, and includes a terminal through hole 39, an electrolyte injection hole 38, and a safety vent (not shown) of a predetermined size. do. The safety vent may be formed in any area as long as it does not interfere with the terminal through hole 39 and the electrolyte injection hole 38, or may be formed on one side of the can 20.

The electrolyte injection hole 38 is for injecting an electrolyte solution that facilitates movement of lithium ions into the can 20 containing the electrode assembly 10. The can 20 is filled with the cap assembly 30. After the sealing, the electrolyte is injected through the electrolyte injection hole 38, and the electrolyte injection hole 38 is sealed with the electrolyte injection hole stopper 37 to completely seal the can 20.

The terminal through hole 39 is for inserting the electrode terminal 31, the electrode terminal 31 and the terminal plate 33 which is located below the cap plate 35 through the terminal through (39) and A gasket 36 is formed to be electrically connected and is formed of a rubber or non-conductive material having good insulation to the outside of the electrode terminal 31 to insulate the electrode terminal 31 and the cap plate 35. .

An insulating plate 34 and a terminal plate 33 are sequentially positioned below the cap plate 35, and the terminal plate 33 is electrically connected to the negative electrode tab 14 of the electrode assembly 10. In addition, the electrode terminal 31 and the negative electrode tab 14 are electrically connected to each other, and the insulating plate 34 electrically insulates the terminal plate 33 and the cap plate 35, thereby providing the cap plate ( Even though the 35 is electrically connected to the positive electrode tab 15 of the electrode assembly 10, the short circuit is not shorted.

The insulating case 32 is positioned at four sides of the electrode assembly 10 to fix the positive electrode tab 15 and the negative electrode tab 14 of the electrode assembly 10. The polypropylene (PP) and the poly It may be formed of an insulating resin such as phenylene sulfite (PPS), polyether sulfone (PES) or modified polyphenylene oxide (PPO), and a space for seating the terminal plate 33 and the insulating plate 34. Supports may be formed at the edges to provide.

The protective circuit board 100 is electrically connected to the bare cell 40 through the first lead terminal 41 and the second lead terminal 42, and includes one or more lead pins 125. The mounting component 120 for controlling voltage or current during charging and discharging of the bare cell 40, an external terminal 150 electrically connected to an external load (not shown), and the bare cell 40 and the mounting component ( And a mounting substrate 110 on which a conductive pattern 140 for electrically connecting the 120 and the external terminal 150 is formed.

Here, the mounting component 120 measures the voltage or current flowing during charging and discharging of the bare cell 40, and controls the voltage and current applied to the bare cell 40 according to the measured voltage or current. The protection circuit board 100 may be a connector for electrically connecting the protection circuit board 100 and the bare cell 40 or the protection circuit board 100 and a separate printed circuit board (not shown).

The mounting substrate 110 is a single layer substrate, and one or more through holes 115 corresponding to the lead pins 125 of the mounting component 120 are formed, and ends of the lead pins 125 It is located inside the through hole 115.

The through hole 115 is filled with a connection member 130 such as a brazing filler metal, and the connection member 130 contacts the conductive patterns 140 formed on both surfaces of the mounting substrate 110 to form the lead pin ( 125 and the conductive pattern 140 are electrically connected to each other. Here, in the first embodiment of the present invention, although the conductive pattern 140 is shown to be formed on both surfaces of the mounting substrate 110, the conductive pattern 140 is formed on one surface of the mounting substrate 110. Can be formed.

In addition, as shown in FIG. 2B, which is another embodiment of the region A illustrated in FIG. 2A, conductive patterns 140 formed on opposite surfaces of the mounting component 120 are formed through both surfaces of the mounting substrate 110. The substantial thickness of the protective circuit board 100 is increased by contacting the conductive pattern 140 with the connection member 130, such as a brazing material, which fills the through-hole 115. Although not prevented, although not shown, an end of the lead pin 125 is in contact with the conductive pattern 140, so that the electrical connection between the lead pin 125 and the conductive pattern 140 is further improved. You can also make it smooth.

As a result, the protection circuit board and the battery pack according to the first embodiment of the present invention form a through hole corresponding to the lead pin of the mounting component in the mounting board which is a single layer substrate, and the end of the lead pin is formed inside the through hole. The lead pin may be minimized, and the mounting area of the mounting component may be minimized, and the lead pin may be electrically connected to a conductive pattern formed on a surface of the mounting substrate by filling the through hole through a connection member such as a solder material. Electrical connection between the conductive pattern and the conductive pattern is prevented from being shorted by an external impact or the like.

(Second embodiment)

3 is a cross-sectional view illustrating a protection circuit board of a battery pack according to a second embodiment of the present invention.

Referring to FIG. 3, the protection circuit board 200 of the battery pack according to the second embodiment of the present invention includes one or a plurality of lead pins 225, and the voltage or the like during charge / discharge of a bare cell (not shown). Mounting component 220 for controlling current, an external terminal (not shown) electrically connected to an external load (not shown), and a conductive pattern for electrically connecting between the bare cell, mounting component 220 and an external terminal. A mounting substrate 210 on which the 240 is formed is included.

Here, the mounting component 220 measures a voltage or current flowing during charging and discharging of the bare cell 40, and controls a plurality of voltages and currents applied to the bare cell according to the measured voltage or current. It may be a protection element of, and may be a connector for electrically connecting between the protection circuit board 200 and the bare cell or protection circuit board 200 and a separate printed circuit board (not shown).

The mounting substrate 210 is a multilayer substrate including a first single layer substrate 212, a second single layer substrate 214, and an insulating layer 216 positioned between the two single layer substrates 212 and 214. One or more through holes 215 are formed corresponding to the lead pins 225 of the component 220, and the ends of the lead pins 225 are located inside the through holes 215. Here, in the second embodiment of the present invention, the mounting substrate 210 is described as two single layer substrates 212 and 214 stacked, but the mounting substrate 210 is a multilayer substrate in which a plurality of single layer substrates are stacked. Can be.

A conductive pattern 240 is formed on both surfaces of the first single layer substrate 212 and the second single layer substrate 214, and a portion of the conductive pattern 240 contacts the through hole 215. Since the through hole 215 is filled with a connection member 230 such as a brazing material, the conductive pattern 240 formed on both surfaces of the first single layer substrate 212 and the second single layer substrate 214 may be formed through the through hole ( The inner side of the 215 is in contact with the connecting member 230 filling the through hole 215, and is electrically connected to the lead pin 225 of the mounting component 220. Here, in the second embodiment of the present invention, although the conductive pattern 240 is shown as being formed on both surfaces of the first single layer substrate 212 and the second single layer substrate 214, the conductive pattern 240 is It may be formed on one surface of the first single layer substrate 212 and the second single layer substrate 214, either one of the first single layer substrate 212 or the second single layer substrate 214 is formed on both surfaces The other one may be formed only on one surface.

In addition, as illustrated in FIG. 2B, a conductive pattern 240 formed on the surface of the first single layer substrate 212 opposite to the mounting component 220 is positioned on the through hole 215. By contacting the conductive pattern 240 with a connection member 230, such as a brazing filler, which fills the through hole 215, a substantial thickness of the protective circuit board 200 may be further prevented from being increased. Although not, the end of the lead pin 225 may be in contact with the conductive pattern 240, so that the electrical connection between the lead pin 225 and the conductive pattern 240 may be more smoothly.

As a result, the protection circuit board and the battery pack according to the second embodiment of the present invention form a through hole corresponding to the lead pin of the mounting component on the mounting board on which a plurality of single layer substrates are stacked, and the end of the lead pin is By positioning the inside of the through-holes, a portion of the conductive pattern formed on one side or both surfaces of each single-layer substrate of the mounting substrate to contact the through-holes, so as to be in contact with the connecting member such as a brazing filler material filling the through-holes, The mounting area of each mounting component may be minimized, and an electrical shock between the conductive pattern and the lead pin may be further prevented from being shorted by an external impact.

(Third embodiment)

4 is a cross-sectional view illustrating a protection circuit board of a battery pack according to a third embodiment of the present invention.

Referring to FIG. 4, the protection circuit board 300 of the battery pack according to the third embodiment of the present invention includes one or a plurality of lead pins 325, and the voltage or the like during charge / discharge of a bare cell (not shown). The mounting component 320 for controlling the current, an external terminal (not shown) electrically connected to an external load (not shown), and a conductive pattern for electrically connecting the bare cell, the mounting component 320 and the external terminal. 340 includes a mounting substrate 310 formed.

Here, the mounting component 320 may be a plurality of protection elements for measuring the voltage or current flowing during charging and discharging of the bare cell, and controlling the voltage and current applied to the bare cell according to the measured voltage or current. The protection circuit board 300 may be a connector for electrically connecting the bare cell or the protection circuit board 300 to a separate printed circuit board (not shown).

The mounting substrate 310 is a multilayer substrate including a first single layer substrate 312, a second single layer substrate 314, and an insulating layer 316 positioned between the two single layer substrates 312 and 314. One or more connecting grooves 315 are formed corresponding to the lead pins 325 of the component 320, and ends of the lead pins 325 are located inside the connection grooves 315. Here, in the third embodiment of the present invention, the mounting substrate 310 is described as two single layer substrates 312 and 314 stacked, but the mounting substrate 310 is a multilayer substrate in which a plurality of single layer substrates are stacked. Can be.

Conductive patterns 340 are formed on both surfaces of the first single layer substrate 312 and the second single layer substrate 314, and are relatively far from the mounting component 320 among the two single layer substrates 312 and 314. A portion of the conductive pattern 340 formed on the surface of the separated first single layer substrate 312 is exposed by the connection groove 315 of the mounting substrate 310, and is formed on both surfaces of the second single layer substrate 314. A portion of the conductive pattern 340 contacts the connection groove 315.

Since the connection groove 315 is filled with a connection member 330 such as a brazing material, the conductive pattern 340 formed on both surfaces of the first single layer substrate 312 may be formed inside the connection groove 315. It comes into contact with the connecting member 330 filling the 315, and is electrically connected to the lead pin 325 of the mounting component 320.

Here, in the third embodiment of the present invention, although the conductive pattern 340 is formed on both surfaces of the first single layer substrate 312 and the second single layer substrate 314, the conductive pattern 340 is May be formed on one surface of the first single layer substrate 312 and the second single layer substrate 314, and may be formed on both surfaces of either the first single layer substrate 312 or the second single layer substrate 314. In the other one, it may be formed only on one surface.

In addition, FIG. 4 of the present invention shows that the connection groove 315 exposes a portion of the conductive pattern 340 formed on the side surface of the mounting part 320 among the surfaces of the first single layer substrate 312. However, the connection groove 315 may expose a part of the conductive pattern 340 formed on the surface opposite to the mounting component 320 among the surfaces of the second single layer substrate 314.

As a result, the protection circuit board and the battery pack according to the third embodiment of the present invention form connection grooves corresponding to the lead pins of the mounting parts on all the single-layer boards of the mounting board on which the plurality of single-layer boards are stacked. End of the is located in the interior of the connection groove, it is possible to minimize the mounting area of the mounting component, and expose a portion of the conductive pattern formed on the surface other than the surface on which the mounting component is located by the connection groove, By filling the connecting groove through a connecting member such as a brazing material, the electrical connection between the lead pin and the conductive pattern formed on the surface of the mounting board is further strengthened, and the electrical connection between the lead pin and the conductive pattern is short-circuited by an external impact or the like. Prevent it.

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

2A and 2B are cross-sectional views illustrating a protection circuit board of a battery pack according to a first embodiment of the present invention.

3 is a cross-sectional view illustrating a protection circuit board of a battery pack according to a second embodiment of the present invention.

4 is a cross-sectional view illustrating a protection circuit board of a battery pack according to a third embodiment of the present invention.

Claims (16)

A mounting component including one or more lead pins; And It includes a mounting substrate formed with one or a plurality of through holes or connecting grooves corresponding to the lead pin, The end of the lead pin is a protective circuit board, characterized in that located in the through hole or the connecting groove. The method of claim 1, The mounting substrate is a protective circuit board, characterized in that a single layer substrate or a multi-layer substrate laminated a plurality of single layer substrate. The method of claim 2, The single layer substrate is a protective circuit board, characterized in that the conductive pattern is formed on one or both surfaces. The method of claim 3, wherein And a connection member filling the through hole or the connection groove and electrically connecting the lead pin and the conductive pattern. The method of claim 4, wherein The connecting member is a protective circuit board, characterized in that the brazing material. The method of claim 3, wherein The mounting substrate is a multilayer substrate, and the through-hole or connecting groove exposes a portion of the conductive pattern formed on the surface of the plurality of single-layer substrate except the surface on which the mounting component is located. The method of claim 6, The lead pin is in contact with the conductive pattern exposed by the through hole or the connecting groove. The method of claim 1, The mounting component is a protective circuit board, characterized in that the protective element or connector. Bare cells; And A protective circuit board electrically connected to the bare cell and including a mounting component including one or more lead pins and a mounting substrate having one or more through holes or connection grooves corresponding to the lead pins; The end of the lead pin is a battery pack, characterized in that located in the through hole or the connecting groove. The method of claim 9, The mounting board of the protective circuit board is a battery pack, characterized in that the single-layer substrate or a multi-layer substrate laminated a plurality of single-layer substrate. The method of claim 10, The single layer substrate is a battery pack, characterized in that the conductive pattern is formed on one or both surfaces. The method of claim 11, The battery pack further comprises a connection member filling the through hole or the connection groove and electrically connecting the lead pin and the conductive pattern. The method of claim 12, The connection member is a battery pack, characterized in that the brazing material. The method of claim 11, The mounting board of the protective circuit board is a multilayer board, and the through hole or the connection groove exposes a part of the conductive pattern formed on the surface of the plurality of single-layer boards except the surface on which the mounting component is located. . The method of claim 14, The lead pin is in contact with the conductive pattern exposed by the through-hole or connecting groove. The method of claim 9, The mounting component is a battery pack, characterized in that the protective element or connector.

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