Secondary battery, secondary battery manufacturing method, secondary battery module, secondary battery pack, and vehicle

Abstract

The invention relates to a secondary battery, a secondary battery manufacturing method, a secondary battery module, a secondary battery pack and a vehicle. The technical problem to be solved is to propose a current path simplification structure for solving the problems of cost increase and performance reduction caused by various components constituting a current path of the secondary battery. To this end, the present invention provides a secondary battery, a method of manufacturing the same, and a vehicle including the same, the secondary battery comprising: a plurality of electrode plates included in the electrode assembly; a plurality of electrode tabs extending from the plurality of electrode plates; a daughter board coupled to the plurality of electrode tabs; the daughter board penetrates through the cover board and is combined with the cover board; and an insulating member formed on the cover plate so as to surround the daughter board.

Description

Technical Field

[0001] The present invention relates to a secondary battery, and more particularly to a secondary battery in which a component constituting a current path of the secondary battery is replaced with a sub-plate. Background Art

[0002] Unlike primary batteries, which cannot be recharged, secondary batteries are batteries that can be charged and discharged. Low-capacity secondary batteries are used in small portable electronic devices such as smartphones, feature phones, notebook computers, digital cameras, and video cameras, while large-capacity secondary batteries are widely used as power sources for motor drives and power storage in hybrid vehicles, electric vehicles, and the like.

[0003] Generally, a secondary battery includes an electrode assembly composed of a positive electrode and a negative electrode, a case accommodating the electrode assembly, a terminal portion connected to the electrode assembly, various components connecting the terminal portion and the electrode assembly, and the like.

[0004] The above information disclosed in this art forming the background of the invention is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not constitute the prior art. Summary of the Invention

[0005] Secondary batteries include various components, such as terminal plates, rivets, current collectors, and lower insulating members, that form a current path between the terminal portion and the electrode assembly. The manufacturing and assembly of these components increases costs, and the current path through these components increases resistance, which can reduce secondary battery performance. Therefore, a simplified current path structure is proposed to reduce secondary battery cost and improve performance.

[0006] However, the technical problems to be solved by the present invention are not limited to the above-mentioned technical problems, and those skilled in the art can clearly understand other technical problems not mentioned from the description of the invention described below.

[0007] A secondary battery according to an embodiment of the present invention for solving the above-mentioned technical problems includes an electrode assembly and a shell for accommodating the electrode assembly. The secondary battery may include: a plurality of electrode plates included in the electrode assembly; a plurality of electrode tabs extending from the plurality of electrode plates; a sub-plate combined with the plurality of electrode tabs; a cover plate, the sub-plate passing through the cover plate and combined with the cover plate; and an insulating component formed on the cover plate in a manner surrounding the sub-plate.

[0008] Furthermore, the manufacturing of a secondary battery according to another aspect of the present invention for solving the above-mentioned technical problems may include the following steps: manufacturing an electrode assembly including a plurality of electrode plates; coupling a plurality of electrode tabs extending from the plurality of electrode plates to a sub-plate; passing through the sub-plate and coupling it to the cover plate; forming an insulating component on the cover plate in a manner that surrounds the sub-plate; and accommodating the electrode assembly in a shell and coupling the cover plate and the shell.

[0009] According to still another aspect of the present invention, there is provided a vehicle including a secondary battery pack manufactured using the secondary battery having the above configuration.

[0010] According to the embodiment of the present invention, components constituting the current path of the secondary battery are replaced with a sub-board, thereby having the effects of reducing the cost of the secondary battery as components are reduced and improving performance by reducing the resistance path length.

[0011] In particular, by removing components such as the terminal plate, rivets, current collector, and lower insulating member that constitute the current path between the terminal portion and the electrode assembly, and removing assembly processes such as welding or riveting, the production cost of the secondary battery can be reduced.

[0012] Furthermore, the contact resistance between components decreases as the number of components decreases, and the component resistance decreases as the current path shortens, thereby having an effect of improving the performance of the secondary battery.

[0013] Furthermore, in a vehicle using the secondary battery of the present invention, the cost of the secondary battery, which accounts for the largest proportion of the vehicle price, can be reduced while improving performance, thereby improving performance such as driving performance and mileage while reducing the vehicle price.

[0014] However, the effects that can be obtained by the present invention are not limited to the above-mentioned effects, and those skilled in the art can clearly understand other technical effects that are not mentioned from the description of the invention described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following drawings attached to this specification illustrate preferred embodiments of the present invention and are used to further understand the technical concept of the present invention in conjunction with the detailed description of the invention described later. Therefore, the present invention should not be interpreted as being limited to the matters described in the drawings.

[0016] Figure 1a This is a perspective view of the upper portion of a conventional prismatic secondary battery.

[0017] Figure 1b yes Figure 1a II′ cross-sectional view.

[0018] Figure 2a FIG. 1 is a side cross-sectional view of a secondary battery according to an embodiment of the present invention.

[0019] Figure 2b FIG. 1 is a plan view of a secondary battery according to an embodiment of the present invention.

[0020] Figure 2c FIG. 1 is a top front view of a secondary battery according to an embodiment of the present invention.

[0021] Figure 3a A diagram showing a current path in a conventional prismatic secondary battery.

[0022] Figure 3b It is a plan view showing a terminal portion of a conventional prismatic secondary battery.

[0023] Figure 3c This is a front view showing a terminal portion of a conventional prismatic secondary battery.

[0024] Figure 4a FIG. 1 is a diagram illustrating a current path of a secondary battery according to an embodiment of the present invention.

[0025] Figure 4b FIG. 1 is a plan view of a terminal portion of a secondary battery according to an embodiment of the present invention.

[0026] Figure 4c FIG. 1 is a front view of a terminal portion of a secondary battery according to an embodiment of the present invention.

[0027] Figures 5a to 5f 1 is a diagram for explaining a method for manufacturing a secondary battery according to an embodiment of the present invention.

[0028] Figure 6 FIG. 1 is an exemplary diagram illustrating a secondary battery module in which secondary batteries are arranged according to an embodiment of the present invention.

[0029] Figure 7 is included Figure 6 An exemplary diagram of a secondary battery pack of the illustrated secondary battery module.

[0030] Figure 8 is included Figure 7 A conceptual diagram of a vehicle illustrating an example of a secondary battery pack. DETAILED DESCRIPTION

[0031] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Before describing, the terms or words used in this specification and claims should not be interpreted as limited to their general or dictionary meanings, but should be interpreted as meanings and concepts that conform to the technical ideas of the present invention based on the principle that the inventor may appropriately define the concepts of terms in order to explain his invention in the best way. Therefore, the embodiments described in this specification and the structures shown in the accompanying drawings are only the most preferred partial embodiments of the present invention and do not represent the entire technical ideas of the present invention. Therefore, it should be understood that at the time of this application, there may be a variety of equivalents and modifications that can replace these.

[0032] Furthermore, when used in this specification, “comprise” and / or “comprising” and / or “including” are used to indicate the existence of specific shapes, numbers, steps, operations, parts, elements and / or combinations thereof, and do not exclude the existence or addition of one or more other shapes, numbers, operations, parts, elements and / or combinations thereof.

[0033] In addition, in order to help understand the invention, the accompanying drawings are not drawn to scale, but the sizes of some components may be exaggerated. In addition, in different embodiments, the same components may be given the same reference numerals.

[0034] When two comparison objects are referred to as "the same," it means "substantially the same." Therefore, "substantially the same" may include cases where there is a deviation that is considered to be relatively low in the art, for example, within 5%. Furthermore, "uniformity" of certain parameters in a predetermined region may mean uniformity from an average perspective.

[0035] Although the terms "first," "second," etc. are used to describe various components, these components are not limited by these terms. These terms are only used to distinguish one component from other components. Unless otherwise specified, the first component can also be the second component.

[0036] Throughout the specification, unless otherwise specified, each component may be in the singular or the plural.

[0037] Arranging an arbitrary component "on the top (or bottom)" of a component or "above (or below)" a component not only means that the arbitrary component is arranged in contact with the top (or bottom) of the component, but also means that other components may be interposed between the component and the arbitrary component arranged above (or below) the component.

[0038] Furthermore, when it is described that a certain component is “on,” “connected to,” or “coupled to” another component, the components may be directly connected or coupled to each other, but it should be understood that another component may be “interposed” between the components, or the components may be “connected,” “coupled,” or “coupled” through another component.

[0039] As used in this specification, the term "and / or" includes any and all combinations of more than one of the associated listed items. In addition, the term "may" used in describing embodiments of the present invention refers to "one or more embodiments of the present invention." The phrase "one or more" and expressions such as "one or more" preceding an item in a list modify the entire item in the list, not the individual items in the list.

[0040] Throughout the specification, when "A and / or B" is mentioned, it means A, B, or A and B unless otherwise stated. When "C to D" is mentioned, it means C or more and D or less unless otherwise stated.

[0041] When statements such as "at least one of A, B, and C," "at least one of A, B, or C," "at least one selected from the group of A, B, and C," or "at least one selected from A, B, and C" are used to specify items of A, B, and C, the statements may refer to any and all suitable combinations.

[0042] The term "use" may be considered synonymous with the term "utilize." As used in this specification, the terms "substantially," "about," and similar terms are used as terms of approximation rather than degree, and are intended to take into account the inherent variations in measured or calculated values ​​that one of ordinary skill in the art would recognize.

[0043] Although the terms first, second, third, etc. may be used in this specification to describe various elements, components, regions, layers, and / or parts, these elements, components, regions, layers, and / or parts should not be limited by these terms. The terms are used to distinguish one element, component, region, layer, or section from another element, component, region, layer, or section. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer, or part discussed below may be referred to as a second element, component, region, layer, or part.

[0044] To illustrate the relationship between one element or feature as shown in the figures and another element or feature, spatially relative terms such as "beneath," "below," "lower," "above," and "upper" may be used in the specification for ease of description. It should be understood that spatial relative positions include not only the orientation depicted in the figures, but also different orientations of the device during use or operation. For example, if the device in the figure is turned over, other elements are understood to be "below" or "below" the other elements, and the illustrated elements are understood to be "above" or "upper" the other elements. Therefore, the term "below" can encompass both directions of above and below.

[0045] The terms used in this specification are used to describe the embodiments of the present invention and are not intended to limit the present invention.

[0046] Types of secondary batteries include coin type, cylindrical type, prismatic type, and pouch type. Since the present invention is basically applicable to prismatic secondary batteries, a prismatic secondary battery will be schematically described first before describing embodiments of the present invention.

[0047] Figure 1a This is a perspective view of the upper part of a conventional prismatic secondary battery. Figure 1b yes Figure 1a II′ cross-sectional view.

[0048] First, yes Figure 1a The appearance of the conventional prismatic secondary battery shown will be described.

[0049] The case 51 forms the overall appearance of the prismatic secondary battery and may be formed using a conductive metal such as aluminum, an aluminum alloy, or nickel-plated steel. In addition, the case 51 may provide a space for accommodating the electrode assembly.

[0050] The cover assembly 60 may include a cover plate 61 covering the opening of the housing 51. The housing 51 and the cover plate 61 may be made of a conductive material. Here, the first terminal 62 and the second terminal 63 may be configured to be electrically connected to the positive or negative electrode inside and extend through the cover plate 61 to protrude outward.

[0051] The cover plate 61 may be formed with an electrolyte injection port 64 to which a sealing plug may be provided, and may be provided with a vent 66 having a notch 65. The vent 66 is used to degas the gas generated inside the battery.

[0052] Reference Figure 1b , the internal structure of the prismatic secondary battery and the coupling structure with the cap assembly 60 are described.

[0053] Figure 1bThe illustrated prismatic secondary battery may basically include an electrode assembly 40 , a first current collecting portion 41 , a first terminal 62 , a second current collecting portion 42 , a second terminal 63 , and a cap assembly 60 .

[0054] The electrode assembly 40 can be formed by winding or stacking a stack of a first electrode plate, a separator, and a second electrode plate formed into a plate shape or a film shape. When the electrode assembly 40 is a wound stack, the winding axis can be parallel to the length direction of the shell 51. In addition, the electrode assembly 40 can be a stacked type instead of a wound type, but in the present invention, the shape of the electrode assembly 40 is not limited. In addition, the electrode assembly 40 can be a Z-stacked electrode assembly in which the first electrode plate and the second electrode plate are inserted into both sides of the separator bent into a Z stack. In addition, the electrode assembly 40 can be one or more electrode assemblies whose long sides are stacked adjacent to each other and housed inside the shell, and in the present invention, the number of electrode assemblies is not limited. The first electrode plate of the electrode assembly 40 can play the role of a negative electrode, and the second electrode plate can play the role of a positive electrode, and vice versa.

[0055] The first electrode plate can be formed by coating a first electrode current collecting plate formed from a metal foil such as copper, copper alloy, nickel, or nickel alloy with a first electrode active material such as graphite or carbon, and can include a first electrode tab (or first uncoated portion) as an area not coated with the first electrode active material. The first electrode tab 43 can serve as a path for current flow between the first electrode plate and the first current collecting portion 41. In some examples, when manufacturing the first electrode plate, the first electrode tab 43 can be pre-cut to protrude toward one side, and can protrude further toward one side than the separator without being separately cut.

[0056] The second electrode plate can be formed by coating a second electrode active material, such as a transition metal oxide, on a substrate formed of a metal foil such as aluminum or an aluminum alloy. The second electrode plate can include a second electrode tab (or second uncoated portion) 44, which is a region not coated with the second electrode active material. The second electrode tab 44 can serve as a path for current flow between the second electrode plate and the second current collecting portion 42. In some examples, when manufacturing the second electrode plate, the second electrode tab 44 can be pre-cut to protrude toward the other side and can protrude further than the separator without being separately cut.

[0057] In some embodiments, the first electrode tab 43 may be located on the right side of the electrode assembly 40, and the second electrode tab 44 may be located on the left side of the electrode assembly 40, or may be located on a side in the same direction. Here, the left and right sides are based on the secondary battery shown in FIG1 for ease of description. When the secondary battery is rotated left or right or up or down, their positions may change.

[0058] The separator allows lithium ions to move while preventing a short circuit between the first electrode plate and the second electrode plate. The separator can be formed using, for example, a polyethylene film, a polypropylene film, or a polyethylene-polypropylene film.

[0059] The first electrode tab 43 of the first electrode plate and the second electrode tab 44 of the second electrode plate extend from both side ends of the electrode assembly 40. In some embodiments, the electrode assembly 40 may be housed in a housing 51 together with the electrolyte.

[0060] In the electrode assembly 40 , first and second electrode tabs 43 and 44 extending from the first and second electrode plates to both sides are connected to the first and second current collecting portions 41 and 42 , respectively, by welding.

[0061] The first current collecting portion 41 and the second current collecting portion 42 are connected to the first current collecting portion 41 and the second current collecting portion 42 through the terminal pins 67 Figure 1a The first terminal 62 and the second terminal 63 described in the foregoing are connected. In some embodiments, the outer peripheral surface of the terminal pin 67 may be threaded and fastened to the first terminal 62 and the second terminal 63 by threaded engagement. However, the present invention is not limited thereto, and the terminal pin 67 may also be coupled to the first terminal 62 and the second terminal 63 by riveting or welding.

[0062] According to one embodiment of the present invention, a secondary battery having Figure 1a and Figure 1b The structure of the conventional prismatic secondary battery shown is different from that of the secondary battery. Figures 2a to 2c The structure of a secondary battery according to one embodiment of the present invention will be described.

[0063] Figure 2a is a side sectional view of a secondary battery according to one embodiment of the present invention, Figure 2b is a plan view of a secondary battery according to an embodiment of the present invention, Figure 2c FIG. 1 is a top front view of a secondary battery according to an embodiment of the present invention.

[0064] Reference Figures 2a to 2c , a secondary battery 100 according to an embodiment of the present invention includes an electrode assembly 110 , a case 120 accommodating the electrode assembly 110 , a plurality of electrode tabs 130 , a sub-plate 140 , a cap plate 150 , and an insulating member 160 .

[0065] The electrode assembly 110 includes a plurality of electrode plates 111 and a plurality of separators 112, and can be formed by winding or stacking a stack of a plurality of electrode plates 111 and a plurality of separators 112 formed in a plate shape or a film shape. In the case where the electrode assembly 110 is a wound stack, the winding axis can be parallel to the length direction of the shell. In addition, the electrode assembly 110 can be a stacked type rather than a wound type, but in the present invention, the shape of the electrode assembly 110 is not limited. In some embodiments, the electrode assembly 110 can be accommodated in the shell 120 together with the electrolyte.

[0066] The plurality of electrode plates 111 may have positive or negative polarity depending on the polarity of the corresponding terminals. In addition, the plurality of electrode plates 111 may include a coated portion coated with an active material and an uncoated portion not coated with the active material. In the case where the plurality of electrode plates 111 are negative electrodes, the plurality of electrode plates 111 may be formed by coating a metal foil such as copper, a copper alloy, nickel, or a nickel alloy with an active material such as graphite or carbon. In the case where the plurality of electrode plates 111 are positive electrodes, the plurality of electrode plates 111 may be formed by coating a metal foil such as aluminum or an aluminum alloy with an active material such as a transition metal oxide.

[0067] The plurality of separators 112 have the function of allowing the movement of lithium ions while preventing short circuits of the plurality of electrode plates 111. The plurality of separators 112 can be formed using, for example, polyethylene film, polypropylene film, polyethylene-polypropylene film, or the like.

[0068] The case 120 forms the overall appearance of the prismatic secondary battery and may be formed using a conductive metal such as aluminum, an aluminum alloy, or nickel-plated steel. In addition, the case 120 may provide a space for accommodating the electrode assembly 110 .

[0069] The plurality of electrode tabs 130 extend from the plurality of electrode plates 111. In one embodiment, the plurality of electrode tabs 130 may extend from uncoated portions of the plurality of electrode plates 111.

[0070] The plurality of electrode tabs 130 are coupled to a sub-plate 140. The sub-plate 140 collects current transmitted from the electrode assembly 110 through the plurality of electrode tabs 130 and transmits it to the outside. In one embodiment, the sub-plate 140 can be made of the same material as the plurality of electrode plates 111 and the plurality of electrode tabs 130. Furthermore, in one embodiment, the sub-plate 140 can be coupled to the plurality of electrode tabs 130 by laser welding.

[0071] The cover plate 150 is combined with the sub-plate 140 by allowing the sub-plate 140 to pass through the cover plate 150. The cover plate 150 may include a through hole for allowing the sub-plate 140 to pass through. The cover plate 150 has a generally rectangular plate shape. The cover plate 150 covers the opening of the shell 120. For example, the cover plate 150 can be coupled to the shell 120 by methods such as laser welding. Similar to the shell 120, the cover plate 150 can be made of a conductive material. In addition, in addition to the through hole, an injection hole 151 for injecting electrolyte, an exhaust hole (not shown) for combining with an exhaust port, etc. may be formed on the cover plate 150. When the internal pressure of the secondary battery rises, the exhaust port is ruptured to discharge gas, and a general exhaust port structure can be applied.

[0072] Insulating member 160 is formed on cover plate 150 to surround sub-board 140. Insulating member 160 is used to insulate sub-board 140 from cover plate 150. Insulating member 160 can be made entirely of insulating material. In one embodiment, insulating member 160 can be formed by insert injection molding to surround sub-board 140.

[0073] The structure of the secondary battery according to one embodiment of the present invention has been described above. Figures 3a to 4c Advantageous effects resulting from structural differences between a secondary battery according to an embodiment of the present invention and a conventional prismatic secondary battery will be described.

[0074] Figure 3a is a diagram showing a current path of a conventional prismatic secondary battery. Figure 3b is a plan view showing a terminal portion of a conventional prismatic secondary battery. Figure 3c This is a front view showing a terminal portion of a conventional prismatic secondary battery.

[0075] Reference Figures 3a to 3c , the current path of the previous prismatic secondary battery includes the terminal plate 210, the rivet 220, the current collector 230, the sub-tab 240 and the lower insulating component 250. In the previous prismatic secondary battery, in the case of the negative terminal, the electron movement path is from the electrode assembly through the sub-tab 240, the current collector 230 and the rivet 220 and is transmitted to the outside through the terminal plate 210. In this way, since the current path of the previous prismatic secondary battery passes through various components, contact resistance is generated between the components, and the current path becomes longer and the component resistance increases, thereby affecting the performance of the secondary battery. In addition, as various components are used, the cost of the secondary battery also increases.

[0076] Figure 4a is a diagram showing a current path of a secondary battery according to an embodiment of the present invention, Figure 4bis a plan view of a terminal portion of a secondary battery according to an embodiment of the present invention, Figure 4c FIG. 1 is a front view of a terminal portion of a secondary battery according to an embodiment of the present invention.

[0077] Reference Figures 4a to 4c , the current path of the secondary battery according to an embodiment of the present invention is composed only of a plurality of electrode tabs 130 and a sub-plate 140. In the secondary battery according to an embodiment of the present invention, in the case of the negative terminal, the movement path of the electrons is directly transmitted from the electrode assembly 110 to the outside through the plurality of electrode tabs 130 and the sub-plate 140. In this way, in the current path of the secondary battery according to an embodiment of the present invention, all components such as the terminal plate, rivets, current collector, lower insulating component, etc. that constitute the current path between the terminal portion and the electrode assembly are removed, so that the contact resistance between the components decreases as the number of components is reduced, and the component resistance decreases as the current path becomes shorter, thereby improving the performance of the secondary battery. In addition, by removing the components that constitute the current path and removing assembly processes such as welding or riveting, the production cost of the secondary battery can be reduced.

[0078] according to Figure 4a The secondary battery according to an embodiment of the present invention may further include a gasket sealing member 170 for sealing between the cap plate 150 and the sub-plate 140. The gasket sealing member 170 is used to prevent liquid such as electrolyte inside the secondary battery or gas generated by chemical reactions inside the secondary battery from leaking to the outside of the secondary battery.

[0079] Figures 5a to 5f 1 is a diagram for explaining a method for manufacturing a secondary battery according to an embodiment of the present invention.

[0080] Reference Figure 5a , an electrode assembly 110 including a plurality of electrode plates 111 is manufactured. At this time, a plurality of electrode tabs 130 may be provided extending from the plurality of electrode plates 111 .

[0081] Reference Figure 5b and Figure 5c The plurality of electrode tabs 130 extending from the plurality of electrode plates 111 are coupled to the sub-plate 140. Figure 5b In the embodiment of the present invention, the plurality of electrode tabs 130 may be bent toward the sub-plate 140 so that the plurality of electrode tabs 130 are in contact with the sub-plate 140. Figure 5c In the embodiment, the plurality of electrode tabs 130 and the sub-plate 140 may be combined by laser welding.

[0082] Reference Figure 5d , the sub-board 140 passes through the cover board 150 and is coupled to the cover board 150. Figure 5dIn the embodiment, a gasket sealing member 170 for sealing between the cover plate 150 and the sub-plate 140 may be sandwiched between the cover plate 150 and coupled to the sub-plate 140 .

[0083] Reference Figure 5e , an insulating component 160 is formed on the cover plate 150 in a manner of surrounding the sub-plate 140. Figure 5e In the embodiment, the insulating component 160 may be formed by insert injection molding to surround the daughter board 140 .

[0084] Reference Figure 5f , the electrode assembly 110 is housed in the housing 120, and the cap plate 150 and the housing 120 are combined. Figure 5f In the embodiment, the cover plate 150 and the housing 120 may be welded together.

[0085] Hereinafter, materials that can be used in the secondary battery according to the present invention will be described.

[0086] As the positive electrode active material, a compound capable of reversibly intercalating and deintercalating lithium (lithiated intercalation compound) can be used. Specifically, one or more composite oxides of lithium and a metal selected from cobalt, manganese, nickel, and combinations thereof can be used.

[0087] The composite oxide may be a lithium transition metal composite oxide, and specific examples thereof include lithium nickel-based oxides, lithium cobalt-based oxides, lithium manganese-based oxides, lithium iron phosphate-based compounds, cobalt-free nickel manganese-based oxides, or combinations thereof.

[0088] As an example, a compound represented by any one of the following chemical formulas can be used. a A 1-b X b O 2-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Mn 2-b X b O 4-c D c (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.05); Li a Ni 1-b-c Co b X c O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni 1-b- c Mn b Xc O 2-α D α (0.90≤a≤1.8, 0≤b≤0.5, 0≤c≤0.5, 0<α<2); Li a Ni b Co c L 1 d G e O2 (0.90≤a≤1.8, 0≤b≤0.9, 0≤c≤0.5, 0≤d≤0.5, 0≤e≤0.1); Li a NiG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a CoG b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-b G b O2 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn2G b O4 (0.90≤a≤1.8, 0.001≤b≤0.1); Li a Mn 1-g G g PO4 (0.90≤a≤1.8, 0≤g≤0.5); Li (3-f) Fe2(PO4)3(0≤f≤2);Li a FePO4 (0.90≤a≤1.8).

[0089] In the above chemical formula, A is Ni, Co, Mn, or a combination thereof; X is Al, Ni, Co, Mn, Cr, Fe, Mg, Sr, V, a rare earth element, or a combination thereof; D is O, F, S, P, or a combination thereof; G is Al, Cr, Mn, Fe, Mg, La, Ce, Sr, V, or a combination thereof; and L 1 It is Mn, Al or a combination thereof.

[0090] A positive electrode for a lithium secondary battery may include a current collector and a positive electrode active material layer formed on the current collector. The positive electrode active material layer includes a positive electrode active material and may further include a binder and / or a conductive material.

[0091] The positive active material may be present in an amount of 90 to 99.5 wt % based on 100 wt % of the positive active material layer, and the binder and the conductive material may be present in an amount of 0.5 to 5 wt % based on 100 wt % of the positive active material layer.

[0092] As the current collector, Al can be used, but is not limited thereto.

[0093] The negative electrode active material includes a material capable of reversibly inserting / extracting lithium ions, lithium metal, an alloy of lithium metal, a material capable of doping and dedoping lithium, or a transition metal oxide.

[0094] The material capable of reversibly inserting / extracting the lithium ions may be a carbon-based negative electrode active material, and may include, for example, crystalline carbon, amorphous carbon, or a combination thereof. As an example of the crystalline carbon, graphite such as natural graphite or artificial graphite can be cited, and as an example of the amorphous carbon, soft carbon, hard carbon, mesophase pitch carbide, calcined coke, etc. can be cited.

[0095] As the material capable of doping and dedoping lithium, a Si-based negative electrode active material or a Sn-based negative electrode active material can be used. The Si-based negative electrode active material may be silicon, a silicon-carbon composite, SiO x (0 < x < 2), a Si-based alloy, or a combination thereof.

[0096] The silicon-carbon composite may be a composite of silicon and amorphous carbon. According to one implementation example, the silicon-carbon composite may be in the form of silicon particles and amorphous carbon coated on the surface of the silicon particles.

[0097] The silicon-carbon composite may also contain crystalline carbon. For example, the silicon-carbon composite may include a core containing crystalline carbon and silicon particles and an amorphous carbon coating on the surface of the core.

[0098] The negative electrode for a lithium secondary battery may include a current collector and a negative electrode active material layer located on the current collector. The negative electrode active material layer may include a negative electrode active material, and may also contain a binder and / or a conductive material.

[0099] For example, the negative electrode active material layer may include 90% to 99% by weight of the negative electrode active material, 0.5% to 5% by weight of the binder, and 0% to 5% by weight of the conductive material.

[0100] As the binder, a non-aqueous binder, an aqueous binder, a dry binder, or a combination thereof can be used. When an aqueous binder is used as the negative electrode binder, a cellulose-based compound capable of imparting viscosity may also be included.

[0101] As the negative electrode current collector, a material selected from a copper foil, a nickel foil, a stainless steel foil, a titanium foil, a nickel foam, a copper foam, a polymer substrate coated with a conductive metal, and a combination thereof can be used.

[0102] The electrolyte for a lithium secondary battery may include a non-aqueous organic solvent and a lithium salt.

[0103] The non-aqueous organic solvent functions as a medium that allows ions involved in the electrochemical reaction of the battery to move.

[0104] The non-aqueous organic solvent may be a carbonate, ester, ether, ketone, alcohol solvent, an aprotic solvent, or a combination thereof, and may be used alone or in combination of two or more.

[0105] When a carbonate-based solvent is used, a cyclic carbonate and a chain carbonate may be used in combination.

[0106] Depending on the type of lithium secondary battery, a separator may be present between the positive electrode and the negative electrode. As such a separator, polyethylene, polypropylene, polyvinylidene fluoride, or a multilayer film of two or more layers thereof may be used.

[0107] The separator may include a porous substrate and a coating layer comprising an organic substance, an inorganic substance, or a combination thereof, located on one surface or both surfaces of the porous substrate.

[0108] The organic matter may include a polyvinylidene fluoride-based polymer or a (meth)acrylic acid-based polymer.

[0109] The inorganic material may include inorganic particles selected from the group consisting of Al2O3, SiO2, TiO2, SnO2, CeO2, MgO, NiO, CaO, GaO, ZnO, ZrO2, Y2O3, SrTiO3, BaTiO3, Mg(OH)2, boehmite, and combinations thereof, but is not limited thereto.

[0110] The organic and inorganic substances may be mixed in one coating layer, or may be present in the form of a stack of a coating layer containing an organic substance and a coating layer containing an inorganic substance.

[0111] Figure 6 1 is a diagram illustrating an example of a secondary battery module in which secondary batteries are arranged according to an embodiment of the present invention. As the capacity of secondary batteries for driving electric vehicles increases, a secondary battery module can be manufactured by arranging and connecting a plurality of secondary battery cells horizontally and / or vertically.

[0112] A plurality of secondary batteries are arranged in a space formed by a pair of opposing end plates 71a, 71b and a pair of opposing side plates 72a, 72b. The arrangement direction and number of the secondary batteries can be designed in such a way as to obtain desired voltage and current specifications.

[0113] Figure 7 is included Figure 6 An exemplary diagram of a secondary battery pack of the illustrated secondary battery module.

[0114] The secondary battery pack 80 can be manufactured by embedding a plurality of secondary battery modules into a pack housing designed to be mounted on an actual product. The pack housing may include a fastening portion and an electrical lead-out portion required for mounting on a product. Figure 7 In the drawings, for convenience of illustration, illustration of related elements such as bus bars, cooling units, and external terminals for electrical connection of the secondary battery is omitted.

[0115] The secondary battery pack can be installed in a vehicle. As an example, the vehicle can be an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle includes a four-wheel drive vehicle or a two-wheel drive vehicle.

[0116] Figure 8 is included Figure 7 A conceptual diagram of a vehicle illustrating an example of a secondary battery pack. Figure 8 A case is illustrated in which the secondary battery pack 80 according to an embodiment of the present invention is mounted on a lower portion of a vehicle body of a vehicle V. The vehicle V operates by receiving electric power from the secondary battery pack 80 according to an embodiment of the present invention.

[0117] Although the present invention has been described above with reference to the limited embodiments and drawings, the present invention is not limited thereto and it is obvious that various modifications and variations can be made by persons having ordinary knowledge in the technical field to which the present invention belongs within the scope equivalent to the technical idea of ​​the present invention and the scope of protection recorded in the claims.

[0118] Description of Reference Signs 40: Electrode assembly; 41: First current collecting portion; 42: Second current collecting portion; 43: First electrode terminal tab; 44: Second electrode terminal tab (second uncoated portion); 51: Housing; 60: Cover assembly; 61: Cover plate; 62: First terminal; 63: Second terminal; 64: Electrolyte injection port; 65: Notch; 66: Exhaust port; 67: Terminal pin; 71a, 71b: End plates; 72a, 72b: Side plates; 80: Secondary battery pack; 100: Secondary battery; 110: Electrode assembly; 111: Electrode plate; 112: Diaphragm; 120: Housing; 130: Electrode tab; 140: Sub-plate; 150: Cover plate; 151: Liquid injection hole; 160: Insulating component; 170: Gasket sealing component; 210: Terminal plate; 220: Rivet; 230: Current collector; 240: Sub-tab; 250: Lower insulating component.

Claims

1. A secondary battery comprising an electrode assembly and a housing for accommodating the electrode assembly, the secondary battery comprising: a plurality of electrode plates included in the electrode assembly; a plurality of electrode tabs extending from the plurality of electrode plates; a daughter board, coupled to the plurality of electrode tabs; a cover plate, wherein the sub-plate passes through the cover plate and is combined with the cover plate; as well as An insulating component is formed on the cover plate so as to surround the sub-plate.

2. The secondary battery according to claim 1, wherein The sub-plate is combined with the plurality of electrode tabs by laser welding.

3. The secondary battery according to claim 1, wherein Also includes: The gasket sealing component is used for sealing between the cover plate and the sub-plate.

4. The secondary battery according to claim 1, wherein The insulating component is formed by insert injection molding so as to surround the sub-board.

5. The secondary battery according to claim 1, wherein The electrode assembly further includes a plurality of separators, The electrode assembly is formed by winding or stacking a stack of the plurality of electrode plates and the plurality of separators formed in a plate shape or a film shape.

6. The secondary battery according to claim 5, characterized in that The separator includes a porous substrate and a coating layer containing organic matter, inorganic matter or a combination thereof located on one surface or both surfaces of the porous substrate.

7. The secondary battery according to claim 1, wherein The plurality of electrode plates include a coating portion coated with an active material and an uncoating portion not coated with the active material.

8. The secondary battery according to claim 7, wherein: The plurality of electrode tabs extend from the non-coating portion.

9. The secondary battery according to claim 1, wherein The secondary battery is prismatic.

10. A method for manufacturing a secondary battery, characterized in that: The steps include: manufacturing an electrode assembly comprising a plurality of electrode plates; coupling a plurality of electrode tabs extending from the plurality of electrode plates to a sub-plate; Make the sub-plate penetrate and connect to the cover plate; forming an insulating member on the cover plate so as to surround the sub-plate; and The electrode assembly is accommodated in a case and the cap plate is combined with the case.

11. The secondary battery manufacturing method according to claim 10, characterized in that: The step of coupling the plurality of electrode tabs to the sub-plate comprises the following steps: bending the plurality of electrode tabs toward the sub-board so that the plurality of electrode tabs are in contact with the sub-board; and The plurality of electrode tabs and the sub-plate are combined by laser welding.

12. The method for manufacturing a secondary battery according to claim 10, wherein: The step of penetrating the sub-board and bonding it to the cover plate comprises the following steps: A gasket sealing member for sealing between the cover plate and the sub-plate is sandwiched between the cover plate and bonded to the sub-plate.

13. The method for manufacturing a secondary battery according to claim 10, wherein: The step of forming the insulating component comprises the following steps: The insulating component is formed by insert injection molding in a manner of surrounding the daughter board.

14. The method for manufacturing a secondary battery according to claim 10, wherein: The steps of manufacturing the electrode assembly include the following steps: The electrode assembly is formed by winding or stacking a stack of the plurality of electrode plates and the plurality of separators formed in a plate shape or a film shape.

15. The secondary battery manufacturing method according to claim 14, characterized in that: The steps of forming the electrode assembly include the following steps: The separator is manufactured by forming a porous substrate and a coating layer including an organic substance, an inorganic substance or a combination thereof located on one surface or both surfaces of the porous substrate.

16. The method for manufacturing a secondary battery according to claim 10, wherein: The steps of manufacturing the electrode assembly include the following steps: The plurality of electrode plates including the coating portion coated with the active material and the uncoating portion not coated with the active material are manufactured.

17. The secondary battery manufacturing method according to claim 16, characterized in that: The step of coupling the plurality of electrode tabs to the sub-plate comprises the following steps: The plurality of electrode tabs are formed extending from the non-coating portion. 18 . A secondary battery module comprising a plurality of secondary batteries according to claim 1 arranged and connected in a horizontal or vertical direction.

19. A secondary battery pack, comprising a plurality of secondary battery modules according to claim 18 housed in a pack casing. 20 . A vehicle comprising the secondary battery according to claim 1 .

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