Cylindrical Battery Cell

Abstract

The present invention discloses a cylindrical battery cell comprising: a cylindrical electrode assembly having a first electrode and a second electrode; a printed circuit board (PCB) having at least one circuit component mounted on its top surface and having a first connection pad and a second connection pad connected to the first electrode and the second electrode, respectively; a first metal plate connecting the first electrode and the first connection pad; and a second metal plate connecting the second electrode and the second connection pad, wherein the first connection pad is formed on the bottom surface of the printed circuit board (PCB) and the first metal plate is connected to the bottom surface of the printed circuit board (PCB).

Description

[Technical field]

[0001] The present invention relates to a rechargeable battery, and more particularly to a cylindrical battery cell that is provided on an electrode assembly and can increase the space utilization of a printed circuit board (PCB) on which circuit components such as safety elements are mounted. [Background technology]

[0002] Chargeable and dischargeable secondary cells, i.e., batteries, are widely used as energy sources for mobile devices such as smartphones. In addition, batteries are also used as energy sources for environmentally friendly automobiles such as electric vehicles and hybrid electric vehicles, which are presented as a solution to solve air pollution caused by gasoline vehicles and diesel vehicles that use fossil fuels. As such, the types of applications using batteries are becoming increasingly diverse, and batteries are expected to be applied to even more fields and products in the future than at present.

[0003] Currently, the types of batteries that are widely used include lithium ion batteries, lithium polymer batteries, nickel cadmium batteries, nickel hydrogen batteries, and nickel zinc batteries. The operating voltage of such a unit battery cell is about 2.5V to 4.5V. Therefore, when a higher output voltage is required, a battery pack is constructed by connecting a plurality of battery cells in series. In addition, a battery pack may be constructed by connecting a plurality of battery cells in parallel depending on the charge / discharge capacity required for the battery pack. For this reason, the number and electrical connection form of battery cells provided in the battery pack can be set in various ways depending on the required output voltage and / or charge / discharge capacity.

[0004] Meanwhile, known types of battery cells include cylindrical, prismatic and pouch-type battery cells. The cylindrical and prismatic battery cells are formed in such a way that an electrode assembly is housed in a cylindrical or prismatic metal can, while the pouch-type battery cell is formed in such a way that an electrode assembly is housed in a pouch-type case made of an aluminum laminate sheet. Here, in the case of a cylindrical battery cell, a separator, which is an insulator, is sandwiched between a positive electrode and a negative electrode, and the electrode assembly is wound up to form a jelly-roll-shaped electrode assembly. The electrode assembly is inserted into the battery can together with an electrolyte, and the opening of the battery can is sealed with a cap to form a cylindrical battery cell.

[0005] However, battery cells have the disadvantage of being vulnerable to safety issues due to the risk of overheating, explosion, etc. caused by overcharging, overcurrent, and other physical external impacts, etc., caused by the inclusion of various flammable materials inside the battery cells. Therefore, the battery cells are configured such that at least one safety element, such as a Positive Temperature Coefficient (PTC) element or a Protection Circuit Module (PCM), is connected to the battery cell to effectively control abnormal states such as overcharging and overcurrent. In this case, the safety element is mounted on a Printed Circuit Board (PCB) and connected to the battery cell.

[0006] The PCB on which such a safety element is mounted is provided on the upper side of the cylindrical battery cell, i.e., on the electrode assembly. The PCB is connected to the electrodes of the cylindrical battery cell through a metal plate. That is, the positive and negative electrodes of the electrode assembly can be electrically connected to the connection pads of the PCB through the metal plate, respectively. At this time, the metal plate is soldered to the top surface of the PCB to electrically connect the battery cell and the PCB. That is, two metal plates connected to the positive and negative electrodes of the electrode assembly, respectively, can be soldered to the top surface of the PCB at a predetermined interval. However, there is a problem that the space utilization of the PCB is reduced due to the metal plate being soldered to the top surface of the PCB. That is, the space on the top surface of the PCB is narrowed by an amount corresponding to the area of ​​the metal plate soldered to the top surface of the PCB, thereby reducing the mounting area of ​​the circuit components.

[0007] The relevant prior art includes the following documents: [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Korean Patent Publication No. 10-2022-0095139 Summary of the Invention [Problem to be solved by the invention]

[0009] The present invention provides a cylindrical battery cell that can increase the space utilization of a PCB on which circuit components such as safety elements are mounted.

[0010] In addition, the present invention provides a cylindrical battery cell that can increase the mounting area for circuit components on the top surface of a PCB, thereby improving space utilization.

[0011] Furthermore, the present invention provides a cylindrical battery cell in which at least a portion of a metal plate connecting an electrode of the battery cell to a PCB is surface-mounted on the bottom surface of the PCB, thereby increasing the space on the top surface of the PCB. [Means for solving the problem]

[0012] A cylindrical battery cell according to an embodiment of the present invention comprises a cylindrical electrode assembly having a first electrode and a second electrode, a printed circuit board (PCB) having at least one circuit component mounted on its top surface and having a first connection pad and a second connection pad connected to the first electrode and the second electrode, respectively, a first metal plate connecting the first electrode and the first connection pad, and a second metal plate connecting the second electrode and the second connection pad, wherein the first connection pad is formed on a bottom surface of the printed circuit board (PCB) and the first metal plate is connected to the bottom surface of the printed circuit board (PCB).

[0013] In addition, the first connection pad is formed by exposing a conductor pattern connected to a first metal plate mounted on the bottom surface of the printed circuit board (PCB) on the bottom surface of the printed circuit board (PCB).

[0014] Furthermore, the first connection pads are formed on both sides in one direction centered around the through hole of the printed circuit board (PCB), or on both sides in another direction perpendicular to the one direction.

[0015] Furthermore, the first connection pad is formed with a predetermined width along the through hole of the printed circuit board (PCB).

[0016] Furthermore, the first metal plate is surface mounted on a bottom surface of the printed circuit board (PCB) and connected to the first connection pad.

[0017] Furthermore, the printed circuit board (PCB) is assembled onto the top of the electrode assembly with the first metal plate mounted on the bottom surface.

[0018] Furthermore, the second connection pad is formed on the top surface of the printed circuit board (PCB) and the second metal plate is connected to the top surface of the printed circuit board (PCB).

[0019] Furthermore, the second connection pad is formed on the bottom surface of the printed circuit board (PCB) and the second metal plate is connected to the bottom surface of the printed circuit board (PCB).

[0020] In addition to these, the second metal plate is connected to the second connection pad via a side surface of the electrode assembly. Effect of the Invention

[0021] In the cylindrical battery cell according to the embodiment of the present invention, at least one of the metal plates is connected to the bottom surface of the PCB, thereby increasing the space utilization of the top surface of the PCB compared to the conventional case. That is, circuit components are mounted on the top surface of the PCB, at least one of the first connection pad and the second connection pad is formed on the bottom surface of the PCB, and the first metal plate and the second metal plate extending from the positive terminal and the negative terminal of the first electrode assembly are connected to the first connection pad and the second connection pad, respectively. In other words, at least one of the first metal plate and the second metal plate is connected to the bottom surface of the PCB.

[0022] Therefore, compared to the conventional technique in which both the first connection pad and the second connection pad were formed on the top surface of the PCB, the present invention reduces the space required to form the connection pads on the top surface of the PCB, thereby increasing the space available for mounting circuit components on the top surface of the PCB, thereby increasing the spatial utilization of the PCB. [Brief description of the drawings]

[0023] [Figure 1] FIG. 2 is a cross-sectional view of a cylindrical battery cell according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram of the top surface of a PCB of a cylindrical battery cell according to one embodiment of the present invention. [Diagram 3] FIG. 2 is a schematic diagram of the bottom surface of a PCB of a cylindrical battery cell according to one embodiment of the present invention. [Figure 4] FIG. 2 is a cross-sectional view of a cylindrical battery cell according to another embodiment of the present invention. [Diagram 5] FIG. 13 is a schematic diagram of the top surface of a PCB of a cylindrical battery cell according to another embodiment of the present invention. [Figure 6] FIG. 13 is a schematic diagram of the bottom surface of a PCB of a cylindrical battery cell according to another embodiment of the present invention. [Figure 7] 1A to 1C are schematic diagrams of one side of a PCB for illustrating various modified embodiments of connection pads formed on a PCB according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] Hereinafter, the embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, and can be embodied in various different forms. The following embodiments are provided for the purpose of making the disclosure of the present invention complete and fully conveying the scope of the invention to those skilled in the art.

[0025] Fig. 1 is a cross-sectional view of a cylindrical battery cell according to an embodiment of the present invention, and Fig. 2 and Fig. 3 are schematic diagrams of the top and bottom surfaces of a printed circuit board of a cylindrical battery cell according to an embodiment of the present invention.

[0026] Referring to FIG. 1, a cylindrical battery cell according to an embodiment of the present invention may include an electrode assembly 100 having a first electrode and a second electrode, a battery can 200 accommodating the electrode assembly 100, a battery cap 300 provided on an opening of the battery can 200 to seal the electrode assembly 100 in the battery can 200, a printed circuit board (PCB) 400 provided on the upper side of the electrode assembly 100 and having circuit components including a safety element mounted thereon, and a metal plate 500 electrically connecting the electrode assembly 100 and the PCB 400, at least a portion of which is connected to a bottom surface of the PCB 400. The cylindrical battery cell may further include an insulating plate 350 provided between the PCB 400 and the electrode assembly 100. That is, in the cylindrical battery cell of the present invention, at least one of the metal plates 500 connected to the first and second electrodes of the electrode assembly 100 is connected to the bottom surface of the PCB 400. Each component of the cylindrical battery cell according to an embodiment of the present invention will be described in more detail below.

[0027] 1. Electrode assembly The electrode assembly 100 may include a first electrode, a second electrode, and a separator sandwiched therebetween. In this case, either one of the first electrode and the second electrode may be a positive electrode, and the other may be a negative electrode. For example, the electrode assembly 100 may include a positive electrode plate formed by applying a positive electrode active material to a positive electrode collector, a negative electrode plate formed by applying a negative electrode active material to a negative electrode collector, and a separator sandwiched between the positive electrode plate and the negative electrode plate to prevent short-circuiting between the two electrodes and to enable the movement of lithium ions. In this case, either one of the first electrode and the second electrode may be a positive electrode plate, and the other may be a negative electrode plate, but the positive electrode plate may be the first electrode, and the negative electrode plate may be the second electrode. The electrode assembly 100 may have a jelly-roll structure, for example. That is, the electrode assembly 100 can be manufactured by stacking sheet-like positive and negative electrode plates at least once with a separator sandwiched between them to form a laminate, and winding the laminate around the center of the winding. An additional separator may be provided on the outer circumferential surface of the electrode assembly 100 for insulation from the battery can 200.

[0028] The positive electrode plate may include a positive electrode collector and a positive electrode active material applied on one or both sides of the positive electrode collector. In this case, a positive electrode uncoated portion where the positive electrode active material is not applied is formed on the positive electrode plate. The positive electrode uncoated portion is provided at the upper part in the height direction of the electrode assembly 100 accommodated in the battery can 200. That is, the positive electrode collector includes a positive electrode uncoated portion where the positive electrode active material is not applied to the long side end and is exposed to the outside of the separator, and a part of the positive electrode uncoated portion itself can be used as a positive electrode terminal. Needless to say, a positive electrode terminal (i.e., a first electrode terminal) can also be joined to the positive electrode uncoated portion. In this case, the positive electrode terminal can be joined to the positive electrode uncoated portion by, for example, welding.

[0029] A metal can be used as the positive electrode current collector. As an example, stainless steel, nickel, aluminum, titanium, or an alloy thereof can be used as the positive electrode current collector. As another example, a positive electrode current collector in which the surface of aluminum or stainless steel is surface-treated with carbon, nickel, titanium, or silver can be used. The positive electrode current collector made of such a material can be provided in the form of a foil, film, sheet, punched (perforated), porous body, foaming agent, or the like.

[0030] The positive electrode active material is a material capable of absorbing or desorbing lithium ions, and may contain at least one selected from a composite oxide with lithium, cobalt, manganese, and nickel. For example, the positive electrode active material may be represented by the general chemical formula A[A x M y ]O 2+z (A includes at least one element selected from Li, Na, and K, M includes at least one element selected from Ni, Co, Mn, Ca, Mg, Al, Ti, Si, Fe, Mo, V, Zr, Zn, Cu, Al, Mo, Sc, Zr, Ru, and Cr, and x≧0, 1≦x+y≦2, −0.1≦z≦2, and the stoichiometric coefficients x, y, and z are selected so that the compound is electrically neutral). In another example, the positive electrode active material may include an alkali metal compound represented by the formula: xLiM 1 O 2 -(1-x)Li 2 M 2 O 3 (M 1 contains at least one element having an average oxidation state of 3, M 2 x may be 1≦x≦1. In yet another example, the positive electrode active material may be represented by the general chemical formula Li a M 1 x Fe 1-x M 2 y P 1-y M 3 z O 4-z (M 1contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, and Al, and M 2 contains at least one element selected from Ti, Si, Mn, Co, Fe, V, Cr, Mo, Ni, Nd, Al, Mg, Al, As, Sb, Si, Ge, V, and S, and M 3 contains a halogen group element that selectively contains F, where 0 < a ≤ 2, 0 ≤ x ≤ 1, 0 ≤ y < 1, 0 ≤ z < 1, and the stoichiometric coefficients a, x, y, and z are selected so that the compound maintains electrical neutrality), or Li 3 M 2 (PO 4 ) 3 (M contains at least one element selected from Ti, Si, Mn, Fe, Co, V, Cr, Mo, Ni, Al, Mg, and Al) may be a lithium metal phosphate represented by

[0031] The negative electrode plate may include a negative electrode current collector and a negative electrode active material applied on one or both sides of the negative electrode current collector. At this time, a non-coated portion of the negative electrode plate where the negative electrode active material is not applied is formed. The non-coated portion of the negative electrode is provided at the lower part in the height direction of the electrode assembly 100 housed in the battery can 200. That is, the non-coated portion of the positive electrode and the non-coated portion of the negative electrode are respectively provided at the upper and lower parts in the height direction of the electrode assembly 100. The negative electrode current collector has a non-coated portion of the negative electrode where the negative electrode active material is not applied at the long side end and is exposed outside the separator, and a part of the non-coated portion of the negative electrode can be used as the negative electrode terminal itself. Needless to say, it is also possible to join the negative electrode terminal (that is, the second electrode terminal) to the non-coated portion of the negative electrode. At this time, the negative electrode terminal can be joined to the non-coated portion of the negative electrode by, for example, welding.

[0032] Metals can be used as the negative electrode current collector. For example, stainless steel, nickel, copper, titanium, or an alloy thereof can be used as the negative electrode current collector. For another example, a copper or stainless steel surface treated with carbon, nickel, titanium, or silver can be used as the negative electrode current collector. The negative electrode current collector made of such a material can be provided in the form of a foil, film, sheet, punched (perforated), porous body, foaming agent, or the like.

[0033] The negative electrode active material is a material capable of absorbing or desorbing lithium ions, and may be a carbon material such as crystalline carbon, amorphous carbon, carbon complex, or carbon fiber, lithium metal, or a lithium alloy. That is, the negative electrode plate may be made of the same material as the positive electrode current collector of the positive electrode plate, and the negative electrode active material may be different from the positive electrode active material. For example, the negative electrode active material may be a carbon material, lithium metal or a lithium metal compound, silicon or a silicon compound, tin or a tin compound, or the like. TiO with a potential of less than 2 V 2 , SnO 2 Metal oxides such as the above can also be used as the negative electrode active material. As the carbon material, both low crystallinity carbon and / or high crystallinity carbon can be used.

[0034] The separator is made of thermoplastic resins such as polyethylene (PE) and polypropylene (PP), and its surface is formed into a porous membrane structure. When the temperature inside the battery rises and approaches the melting point of the thermoplastic resin, the separator melts and closes up, becoming an insulating film. By changing into an insulating film, the movement of lithium ions between the positive and negative plates is blocked, and no more current can flow, which stops the temperature rise inside the battery.

[0035] The separator may be a porous polymer film, for example, a porous polymer film made of a polyolefin polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, an ethylene / methacrylate copolymer, etc., either alone or in combination. As another example, the separator may be a normal porous nonwoven fabric, for example, a nonwoven fabric made of a high-melting point glass fiber, a polyethylene terephthalate fiber, etc.

[0036] A coating layer of inorganic particles can be formed on at least one surface of the separator. The separator itself can also be made of a coating layer of inorganic particles. The particles constituting the coating layer can have a structure in which they are bound to a binder so that there is an interstitial volume between adjacent particles. The inorganic particles can be made of an inorganic material having a dielectric constant of 5 or more. For example, the inorganic particles can be Pb(Zr,Ti)O 3 (PZT), Pb 1-x La x Zr 1-y Ti y O 3 (PLZT), PB(Mg 3 Nb 2 / 3 )O 3 -PbTiO 3 (PMN-PT), BaTiO 3 , hafnia (HfO 2 ), SrTiO 3 , TiO 2 , Al 2 O 3 , ZrO 2 , SnO 2 , CEO 2 , MgO, CaO, ZnO and Y 2 O 3 The composition may contain at least one substance selected from the group consisting of:

[0037] 2. Battery can The battery can 200 is a generally cylindrical container having an open upper end, and contains the electrode assembly 100 and an electrolyte. That is, the battery can 200 is manufactured in a shape in which the upper part is open and the lower part (i.e., bottom part) and the side are closed to contain the electrode assembly 100 and the electrolyte. Here, the lower part and the side of the battery can 200 may be integrally formed, or the lower part and the side may be provided separately and combined with each other by welding or the like. Such a battery can 200 can be manufactured from a material having electrical conductivity, such as a metal. The material of the battery can 200 can be a lightweight and flexible metal material, such as aluminum, an aluminum alloy, or stainless steel, or steel or nickel-plated steel.

[0038] Meanwhile, the battery can 200 may be configured to have different thicknesses at different positions. For example, the battery can 200 may be formed so that the thickness of the side surface is thinner than the thickness of the bottom surface. When the side surface is formed thin, the diameter of the electrode assembly 100 may be made larger, which may be advantageous in terms of energy density.

[0039] The bottom part of the battery can 200, i.e., the bottom surface, can have a thickness of, for example, 0.4 mm to 1.2 mm, and more preferably, 0.6 mm to 1.0 mm. If the thickness of the bottom part of the battery can 200 is too thin, there is a risk that the internal pressure will increase or the battery can 200 will be distorted during welding. Conversely, if the thickness of the bottom part of the battery can 200 is too thick, there is a concern that it will be difficult to process the battery can 200, and there is a risk that the loss of energy density will be large. Therefore, it is necessary to manage the thickness of the bottom part of the battery can 200 to an appropriate level.

[0040] In addition, the side wall portion of the battery can 200 forming the outer circumferential surface may have a thickness of, for example, 0.3 mm to 0.8 mm, and more preferably, 0.4 mm to 0.6 mm. If the thickness of the side wall portion of the battery can 200 is too thin, there is a high possibility that a fire will spread to adjacent cylindrical battery cells when a cylindrical battery cell ignites and explodes. For example, in a battery pack including a plurality of cylindrical battery cells, if an abnormality occurs in some cylindrical battery cells and ignites and explodes, if the thickness of the side wall portion of the battery can 200 is too thin, there is a risk of pinholes being formed, which may increase the risk of chain fires and explosions. On the other hand, if the thickness of the side wall portion of the battery can 200 is too thick, there is a concern that it may become difficult to process the battery can 200, and there is a risk of a large loss of energy density. Therefore, it is necessary to manage the thickness of the side wall portion of the battery can 200 to an appropriate level. Meanwhile, a plating layer can be formed on the battery can 200. In this case, the plating layer may contain, for example, nickel (Ni) and the thickness of the plating layer may be 1.5 μm to 6.0 μm.

[0041] 3. Battery cap The battery cap 300 may be made of a metal material. The battery cap 300 being made of a metal material makes it possible to ensure the rigidity of the cylindrical battery cell. The battery cap 300 seals an opening formed at the upper end of the battery can 200. That is, the battery cap 300 forms the upper surface of the cylindrical battery cell. At this time, even if the battery cap 300 is made of a conductive metal material, it may not have polarity. Therefore, the battery cap 300 is not electrically connected to the electrode assembly 100. In this way, when the battery cap 300 is not electrically connected to the electrode assembly 100, the battery cap 300 does not function as a positive terminal or a negative terminal. That is, the battery cap 300 does not need to be electrically connected to the electrode assembly 100 and the battery can 200, and the material thereof is not necessarily a conductive metal.

[0042] Meanwhile, a seal gasket (not shown) may be interposed between the battery cap 300 and the battery can 200 to seal the opening at the top end of the battery can 200 and electrically insulate the battery can 200 from the battery cap 300. The seal gasket may include a material having insulating properties and elasticity. The seal gasket may include, for example, a polymer resin. The battery cap 300 may include a protrusion protruding upward from approximately the center thereof. The battery cap 300 may further include a vent portion formed to prevent the internal pressure from increasing beyond a set value due to gas generated inside the battery can 200. The set internal pressure value may be approximately 15 to 35 kgf / cm. The vent portion corresponds to a region of the battery cap 300 that has a smaller thickness than the surrounding region. The vent portion is structurally weaker than the surrounding region. Therefore, if an abnormality occurs in the cylindrical battery cell and the pressure inside the battery can 200 increases above a certain level, the vent breaks and the gas generated inside the battery can 200 is discharged. The vent can be formed, for example, by cutting out one or both sides of the battery cap 300 (forming a cutout on one or both sides) to partially reduce the thickness of the battery cap 300.

[0043] 4. Printed Circuit Boards (PCBs) The printed circuit board (PCB) 400 is provided on the upper side of the electrode assembly 100 in the battery can 200. In this case, an insulating plate 350 may be provided between the PCB 400 and the electrode assembly 100. The insulating plate 350 is provided on the electrode assembly 100, and the PCB 400 is provided on the upper side thereof, so that the electrode assembly 100 and the PCB 400 can be insulated from each other. Such a PCB 400 has a shape of a generally cylindrical battery cell. In addition, the size of the PCB 400 corresponds to the size of the electrode assembly 100. That is, the PCB 400 may be provided in the shape of a generally circular plate having a predetermined thickness and a size corresponding to the size of the electrode assembly 100. And, the PCB 400 has a through hole 410 in the center. That is, the PCB 400 may have a through hole 410 in a region corresponding to the winding center of the electrode assembly 100.

[0044] Such a PCB 400 may be composed of at least one insulating layer and at least one conductive pattern. The insulating layer of the PCB 400 may be made of ceramic, an organic / inorganic composite material, or a glass fiber impregnated material. When the insulating layer contains a polymer resin, it may contain an epoxy-based insulating resin such as glass cloth-based epoxy resin laminate (FR-4: Flame Retardant Type 4), bismaleimide triazine (BT: Bismaleimide Triazine), or Ajinomoto Buildup Film (ABF: Ajinomoto Buildup Film), or may contain a polyimide-based resin. On the other hand, when the insulating layer is laminated in a plurality of layers, the plurality of insulating layers may all be formed of the same material, or at least one layer may be formed of a material different from the other layers. Also, the conductive pattern can be formed in a predetermined shape on at least one surface of the insulating layer. For example, a copper clad laminate (CCL) having conductive layers formed on one surface and the other surface of the insulating layer can be used, and the conductive layer on the insulating layer can be patterned to form the conductive pattern. Needless to say, a plating process may be performed to form conductive patterns on one side and the other side of the insulating layer. In addition, when a plurality of insulating layers are laminated, a conductive pattern may be formed on one side and the other side of the central insulating layer, upper and lower insulating layers may be formed on the upper and lower parts of the central insulating layer, respectively, and a conductive pattern of a predetermined shape may be formed on one side (e.g., the upper side) of the upper insulating layer and one side (e.g., the lower side) of the lower insulating layer. The conductive patterns on the upper and lower insulating layers may be formed by patterning the conductive layer, or may be formed into a predetermined pattern by performing a plating process on the insulating layer. As described above, the PCB 400 may be formed by forming a conductive pattern of a predetermined shape on the surface of an insulating layer, and laminating a plurality of insulating layers on which the conductive patterns are formed. Such a PCB 400 may be formed into a single-sided board, a double-sided board, a multi-layer board, etc., depending on the number of insulating layers and the laminated number of conductive patterns. The greater the number of layers, the better the mounting ability of electronic components, and it is used for high-definition products, so the number of layers may be selected depending on the number and integration level of components to be mounted on the PCB.

[0045] As shown in Fig. 2, a plurality of circuit components 420 (421, 422, 423) can be mounted on the top surface of the PCB 400. The circuit components 420 may include at least one safety element such as a Positive Temperature Coefficient (PTC) element 421 and a Protection Circuit Module (PCM) 422 so as to effectively control abnormal states such as overcharging and overcurrent. The PTC element 421 has a significantly increased resistance to cut off the internal circuit of the battery when abnormal heat is generated due to overcharging or an internal short circuit of the battery. The circuit components 420 may also include an electric circuit element 423 including an element such as a control IC, a charge / discharge switch, and a temperature fuse.

[0046] In addition, the PCB 400 may have connection pads 431, 432 on the top and bottom surfaces to which the metal plates 510, 520 are connected. That is, the PCB 400 may have a first connection pad 431 on the bottom surface to be connected to the first metal plate 510, and a second connection pad 432 on the top surface to be connected to the second metal plate 520. The first metal plate 510 is connected to the positive electrode plate or positive electrode terminal of the electrode assembly 100, and the second metal plate 520 is connected to the negative electrode plate or negative electrode terminal of the electrode assembly 100. That is, the PCB 400 of the present invention is connected to the positive electrode terminal via the first metal plate 510 on the bottom surface, and connected to the negative electrode terminal via the second metal plate 520 on the top surface. At this time, the first connection pad 431 is formed by exposing a conductor pattern electrically connected to the first metal plate 510 mounted on the bottom surface of the PCB 400 on the bottom surface of the PCB 400. Also, the conductor pattern electrically connected to the first metal plate 510 may be electrically connected in one direction of the first metal plate 510 or in both directions of the first metal plate 510. Meanwhile, the first connection pad 431 is formed adjacent to the through hole 410, and the second connection pad 432 is formed far from the through hole 410. However, the positions of the first connection pad 431 and the second connection pad 432 can be changed in various ways so that the first connection pad 431 is formed on the bottom surface of the PCB 400 and the second connection pad 432 is formed on the top surface of the PCB 400. In this manner, by forming the first connection pads 431 on the bottom surface of the PCB 400, it becomes possible to form a predetermined conductive pattern inside the PCB 400 for electrical connection with the circuit component 420 mounted on the top surface of the PCB 400. That is, a conductive pattern for connecting the first connection pads 431 on the bottom surface of the PCB 400 and the circuit component 420 on the top surface of the PCB 400 can be formed inside the PCB 400. For this purpose, the conductive pattern can be formed penetrating at least one insulating layer.In this manner, by forming the first connection pads 431 and the second connection pads 432, to which the metal plate 500 is connected, on the top and bottom surfaces of the PCB 400, respectively, the area of ​​the connection pads on the top surface of the PCB 400 becomes smaller than in the past, thereby increasing the space utilization of the PCB 400. That is, in the past, the first connection pads and the second connection pads were formed on the top surface of the PCB 400, and the space by the connection pads became narrower, thereby reducing the space utilization of the PCB 400.

[0047] 5. Metal plate The metal plate 500 is provided to connect the electrode assembly 100 and the PCB 400. The metal plate 500 may include a first metal plate 510 for connecting a positive terminal or a positive plate of the electrode assembly 100 to the PCB 400, and a second metal plate 520 for connecting a negative terminal or a negative plate of the electrode assembly 100 to the PCB 400. The first metal plate 510 connects a positive plate or a positive terminal located on the upper side of the electrode assembly 100 to a bottom surface of the PCB 400. That is, the positive plate of the electrode assembly 100 is connected to a first connection pad 431 on the bottom surface of the PCB 400 via the first metal plate 510, and is thereby connected to the PCB 400. At this time, the first metal plate 510 is connected on the first connection pad 431 by surface mount technology (SMT). Also, the second metal plate 520 connects the negative electrode terminal or negative electrode plate located on the lower side of the electrode assembly 100 to the top surface of the PCB 400. That is, the negative electrode plate of the electrode assembly 100 is connected to the second connection pad 432 on the top surface of the PCB 400 via the second metal plate 520, and is thereby connected to the PCB 400. For this purpose, the second metal plate 520 is connected to the PCB 400 via the second connection pad 432 on the top surface of the PCB 400 via the side surface of the electrode assembly 100. That is, the second metal plate 520 extends from the negative electrode plate on the lower side of the electrode assembly 100 along the side surface of the electrode assembly 100 to the second connection pad 432 on the top surface of the PCB 400. At this time, since a separator may be formed on the outermost periphery of the electrode assembly 100, the second metal plate 520 may be insulated from the positive electrode plate or the negative electrode plate of the electrode assembly 100, and since an insulator may also be coated on the inner surface of the battery can 200, the second metal plate 520 may also be insulated from the battery can 200. Meanwhile, the PCB 400 may be assembled on the top of the electrode assembly 100 with the first metal plate 510 mounted on the bottom surface.

[0048] As described above, in the cylindrical battery cell according to the embodiment of the present invention, the metal plates 500 are respectively connected to the top and bottom surfaces of the PCB 400, thereby increasing the space utilization of the top surface of the PCB 400 compared to the conventional case. That is, in the embodiment of the present invention, the first connection pad 431 and the second connection pad 432 are respectively formed on the bottom and top surfaces of the PCB 400, and the first metal plate 510 and the second metal plate 520 extending from the positive terminal and the negative terminal of the first electrode assembly 100 are respectively connected to the first connection pad 431 and the second connection pad 432. Therefore, in the present invention, compared to the conventional case in which the first connection pad and the second connection pad are formed on the top surface of the PCB 400, the space for forming the connection pads on the top surface of the PCB 400 is narrowed, and therefore the space in which the circuit components can be mounted is increased, thereby increasing the space utilization of the PCB 400.

[0049] FIG. 4 is a cross-sectional view of a cylindrical battery cell according to another embodiment of the present invention. Also, FIGS. 5 and 6 are schematic diagrams of the top and bottom surfaces of a printed circuit board of a cylindrical battery cell according to an embodiment of the present invention. In the cylindrical battery cell according to another embodiment of the present invention, as shown in FIGS. 4 to 6, the lower part of the electrode assembly 100, i.e., the second metal plate 520 connected to the negative terminal of the electrode assembly 100, is mounted on the bottom surface of the PCB 400. That is, in another embodiment of the present invention, the first metal plate 510 and the second metal plate 520 are connected to the bottom surface of the PCB 400, and therefore, the first connection pad 431 and the second connection pad 432 connected to the first metal plate 510 and the second metal plate 520, respectively, can be formed separately from each other on the bottom surface of the PCB 400. All other configurations are the same as those described in the embodiment of the present invention.

[0050] Meanwhile, the connection pad to which the metal plate of the present invention is connected can be modified into various shapes. That is, the first connection pad 431 formed on the bottom surface of the PCB 400 and to which the first metal plate 510 is connected may be formed with a predetermined width along the through hole 410 of the PCB 400 as shown in (a) of FIG. 7, may be formed on both sides in one direction centered on the through hole 410 as shown in (b) of FIG. 7, or may be formed on both sides in another direction perpendicular to the one direction of (b) of FIG. 7 centered on the through hole 410 as shown in (c) of FIG. In this case, the first connection pad 431 may be formed apart from the second connection pad 432. Needless to say, various modified embodiments of the first connection pad 431 shown in FIG. 7 can also be applied to the embodiment of the present invention described using FIG. 2 and FIG. 3. That is, even if the first connection pad 431 is formed on the bottom surface of the PCB 400 and the second connection pad 432 is formed on the top surface of the PCB 400, the first connection pad 431 can be deformed into a wide variety of shapes as shown in FIG. 7. In addition, various modified shapes can also be applied to the second connection pad 432. That is, the second connection pad 432 may be formed with a predetermined width along the through hole 410, may be formed on both sides in one direction centered on the through hole 410, or may be formed on both sides in another direction perpendicular to the one direction centered on the through hole 410. When the second connection pad 432 is formed in such a shape, the first connection pad 431 may be formed in a square shape.

[0051] As described above, in the cylindrical battery cell according to another embodiment of the present invention, the metal plate 500 is connected to the bottom surface of the PCB 400, thereby increasing the space utilization of the top surface of the PCB 400 compared to the conventional method. That is, in another embodiment of the present invention, the first connection pad 431 and the second connection pad 432 are formed on the bottom surface of the PCB 400, respectively, and the first metal plate 510 and the second metal plate 520 extending from the positive terminal and the negative terminal of the first electrode assembly 100 are connected to the first connection pad 431 and the second connection pad 432, respectively. Therefore, in the present invention, compared to the conventional method in which the first connection pad and the second connection pad are formed on the top surface of the PCB 400, the space for forming the connection pads on the top surface of the PCB 400 is narrowed, thereby increasing the space in which circuit components can be mounted, and as a result, the space utilization of the PCB 400 can be increased.

[0052] Although the technical concept of the present invention as described above has been specifically described based on the above embodiment, it should be noted that the above embodiment is for the purpose of explanation and is not intended to limit the invention. It should be understood that a person skilled in the art of the present invention can implement various embodiments within the scope of the technical concept of the present invention.

[0053] The names of the symbols used in this specification and the drawings are as follows: [Explanation of symbols]

[0054] 100: Electrode assembly 200: Battery can 300: Battery cap 400: Printed circuit board 500: Metal plate

Claims

1. a cylindrical electrode assembly including a first electrode and a second electrode; a printed circuit board (PCB) having at least one circuit component mounted on a top surface thereof and including a first connection pad and a second connection pad connected to the first electrode and the second electrode, respectively; a first metal plate connecting the first electrode and the first connection pad; a second metal plate connecting the second electrode and the second connection pad; Equipped with A cylindrical battery cell, wherein the first connection pad is provided on a bottom surface of the printed circuit board (PCB), and the first metal plate is connected to the bottom surface of the printed circuit board (PCB).

2. 2. The cylindrical battery cell according to claim 1, wherein the first connection pad is a conductor pattern connected to a first metal plate mounted on the bottom surface of the printed circuit board (PCB) and exposed on the bottom surface of the printed circuit board (PCB).

3. 3. The cylindrical battery cell according to claim 2, wherein the first connection pads are provided on both sides in one direction around the through hole of the printed circuit board (PCB) or on both sides in another direction perpendicular to the one direction.

4. 3. The cylindrical battery cell according to claim 2, wherein the first connection pad is provided with a predetermined width along a through hole of the printed circuit board (PCB).

5. 3. The cylindrical battery cell according to claim 2, wherein the first metal plate is surface mounted to a bottom surface of the printed circuit board (PCB) and connected to the first connection pad.

6. 6. The cylindrical battery cell according to claim 5, wherein the printed circuit board (PCB) is assembled on the top of the cylindrical electrode assembly with the first metal plate mounted on a bottom surface thereof.

7. 7. The cylindrical battery cell according to claim 6, wherein the second connection pad is provided on a top surface of the printed circuit board (PCB), and the second metal plate is connected to the top surface of the printed circuit board (PCB).

8. 7. The cylindrical battery cell according to claim 6, wherein the second connection pad is provided on a bottom surface of the printed circuit board (PCB), and the second metal plate is connected to the bottom surface of the printed circuit board (PCB).

9. 9. The cylindrical battery cell according to claim 7, wherein the second metal plate is connected to the second connection pad via a side surface of the cylindrical electrode assembly.

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