Secondary battery, battery pack including the same, and automobile

Abstract

One embodiment of the present invention provides a secondary battery including: an electrode assembly in which a first electrode, a separator, and a second electrode are sequentially stacked and wound; and a battery can accommodating the electrode assembly and an electrolyte, the battery can having a bottom on one side, an open portion on the other side opposite the bottom, and a cylindrical sidewall, the electrode assembly having a first end from which the first electrode tab is pulled out and a second end from which the second electrode tab is pulled out, the first end and the battery can being electrically connected, the sidewall of the battery can including an insulating coating layer provided on an inner surface corresponding to the second end, a second current collector electrically connected to the second electrode tab, and an insulating member provided between the second current collector and the bottom of the battery can, thereby providing an effect of increasing a space available for the electrode assembly accommodated in the battery can.

Description

[Technical Field]

[0001] The present invention relates to a secondary battery, a battery pack including the same, and an automobile.

[0002] This application claims the benefit of the filing date of Korean Patent Application No. 10-2021-0160776, filed with the Korean Intellectual Property Office on November 19, 2021, the entire contents of which are incorporated herein by reference. [Background technology]

[0003] Secondary batteries, which are highly adaptable to various products and have electrical properties such as high energy density, are widely used not only in portable devices but also in electric vehicles (EVs) and hybrid electric vehicles (HEVs) that are powered by electrical sources.

[0004] Such secondary batteries have the main advantage of dramatically reducing the use of fossil fuels, as well as the advantage of not producing any by-products from the use of energy, and are therefore attracting attention as a new energy source that is environmentally friendly and improves energy efficiency.

[0005] Currently, widely used types of secondary batteries include lithium-ion batteries, lithium polymer batteries, nickel-cadmium batteries, nickel-metal hydride batteries, and nickel-zinc batteries. The operating voltage of such unit secondary battery cells, i.e., unit battery cells, is approximately 2.5V to 4.5V. Therefore, if a higher output voltage is required, a battery pack may be configured by connecting multiple battery cells in series. Alternatively, a battery pack may be configured by connecting multiple battery cells in parallel depending on the required charge / discharge capacity of the battery pack. Therefore, the number and electrical connection form of battery cells included in the battery pack can be variously set depending on the required output voltage and / or charge / discharge capacity.

[0006] Meanwhile, known types of secondary battery cells include cylindrical, prismatic, and pouch-shaped batteries. In the case of cylindrical batteries, a separator, which is an insulator, is interposed between a positive electrode and a negative electrode, and the separator is wound up to form a jelly-roll-like electrode assembly. The electrode assembly is then inserted into a battery can together with an electrolyte to form a battery.

[0007] In this case, the positive electrode terminal of the cylindrical secondary battery is replaced with a structure in which a rivet-type positive electrode terminal penetrates the bottom surface of the battery can, instead of the conventional sealing cap that seals the open part of the battery can. Accordingly, an insulator is applied to insulate the components electrically connected to the positive electrode terminal (for example, the positive electrode current collector plate and the end where the positive electrode tab is pulled out) from the negative electrode, which has the opposite polarity.

[0008] However, the insulator has a thick shape that encloses both the positive electrode current collector plate and the end portion from which the positive electrode tab is pulled out, resulting in unnecessary loss of space.

[0009] Therefore, the insulator occupies a large proportion of the interior of the battery can, which reduces the size of the electrode assembly that can be housed in the same battery can, resulting in a problem of reduced capacity of the secondary battery. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention aims to provide a secondary battery that alleviates the problem of capacity reduction due to a reduction in the diameter of an electrode assembly while efficiently ensuring insulation, and to provide a battery pack and a vehicle including the same.

[0011] SUMMARY OF THE INVENTION An object of the present invention is to provide a secondary battery with a simplified assembly process for improving process efficiency. [Means for solving the problem]

[0012] The present inventors have found that the above problem can be solved by changing the shape of the insulator included in the secondary battery. Specifically, the present inventors have found that by providing different insulating materials in a portion of the battery can that contacts the current collector plate of the opposite polarity and a portion of the battery can that contacts the electrode tab of the opposite polarity, it is possible to provide more space for the electrode assembly.

[0013] The present invention provides a secondary battery having the above technical features, a battery pack including the same, and a vehicle.

[0014] One embodiment of the present invention provides a secondary battery including: an electrode assembly in which a first electrode, a separator, and a second electrode are sequentially stacked and wound; and a battery can containing the electrode assembly and an electrolyte, wherein the battery can has a bottom on one side, an open portion on the other side opposite the bottom, and a cylindrical sidewall, the electrode assembly has a first end from which the first electrode tab is extended and a second end from which the second electrode tab is extended, the first end and the battery can being electrically connected, the sidewall of the battery can including an insulating coating layer formed on an inner surface corresponding to the second end, a second current collector plate electrically connected to the second electrode tab, and an insulating member provided between the second current collector plate and the bottom of the battery can.

[0015] Another embodiment of the present invention provides a battery pack including at least one of the secondary batteries.

[0016] Finally, one embodiment of the present invention provides a vehicle including at least one of the battery packs described above. [Effects of the Invention]

[0017] According to an embodiment of the present invention, the process of insulating the battery can and the current collector plate of the opposite polarity and the electrode end of the opposite polarity from the battery can by wrapping them with an insulating material (e.g., an insulator) at once, and the process of additionally insulating the electrode end of the opposite polarity by wrapping it with an additional insulating material (e.g., insulating tape) one or more times are omitted, thereby simplifying the insulation process while ensuring the desired insulation effect.

[0018] Furthermore, according to an embodiment of the present invention, the battery can and the current collector plate of the opposite polarity and the electrode end of the opposite polarity are all wrapped in a single thick insulating member (e.g., an insulator), which prevents the problem of the space occupied by the electrode assembly being relatively reduced during insulation, and therefore the diameter of the electrode assembly that can be accommodated in a battery can of the same specification can be increased.

[0019] Furthermore, according to the embodiment of the present invention, the insulating member contains a highly heat-resistant material, and therefore, when the internal temperature of the battery rises to a high temperature, an excellent heat dissipation effect can be exhibited.

[0020] Therefore, the secondary battery according to the embodiment of the present invention can increase the battery capacity while maintaining the insulation at a reasonable level, and can expect a heat dissipation effect due to an increase in the internal temperature, thereby realizing a high energy density and reducing costs. [Brief explanation of the drawings]

[0021] [Figure 1] 1 shows a conventional secondary battery. [Figure 2] 1 shows a secondary battery structure according to one embodiment of the present invention. [Figure 3] 1 shows a secondary battery structure according to one embodiment of the present invention. [Figure 4] 1 is a diagram showing a schematic configuration of a battery pack including a secondary battery according to an embodiment of the present specification. [Figure 5] FIG. 1 is a diagram showing a schematic configuration of a vehicle including a battery pack according to an embodiment of the present specification. DETAILED DESCRIPTION OF THE INVENTION

[0022] The terms and words used in this specification and claims should not be interpreted in a limited manner based on their ordinary or dictionary meanings, but should be interpreted in a meaning and concept that is consistent with the technical idea of the present invention, based on the principle that an inventor can appropriately define the concept of a term in order to best describe his or her invention.

[0023] Throughout the specification, when a part "comprises" a certain element, this does not mean that it excludes other elements, but that it may further include other elements, unless otherwise specified. Furthermore, terms such as "part," "device," etc. used in this specification refer to a unit that performs at least one function or operation.

[0024] An embodiment of the present invention will now be described.

[0025] One embodiment of the present invention provides a secondary battery including: an electrode assembly in which a first electrode, a separator, and a second electrode are sequentially stacked and wound; and a battery can containing the electrode assembly and an electrolyte, wherein the battery can has a bottom on one side, an open portion on the other side opposite the bottom, and a cylindrical sidewall, the electrode assembly has a first end from which the first electrode tab is extended and a second end from which the second electrode tab is extended, the first end and the battery can being electrically connected, the sidewall of the battery can including an insulating coating layer formed on an inner surface corresponding to the second end, a second current collector plate electrically connected to the second electrode tab, and an insulating member provided between the second current collector plate and the bottom of the battery can.

[0026] In this specification, the first electrode and the second electrode are electrodes of opposite polarity, one of which is a positive electrode and the other is a negative electrode. In this specification, the first electrode and the second electrode may have a sheet shape, but any electrode known in the art may be used without limitation.

[0027] In the present specification, the separator refers to an insulator interposed between a first electrode and a second electrode to prevent short-circuiting between the first electrode and the second electrode of opposite polarity and / or to insulate the first electrode and the second electrode. In the present specification, the separator may have a sheet shape. In the present specification, the separator may be a thin insulating film having high ion permeability and mechanical strength, but any separator known in the art may be used without limitation.

[0028] In this specification, the electrolyte is a non-aqueous electrolyte containing a lithium salt, and is mainly used in a liquid phase, but any electrolyte known in the art may be used without limitation.

[0029] In this specification, the battery can may contain iron, nickel, or an alloy thereof, or may be plated with these materials, but any battery can known in the art may be used without limitation.

[0030] In this specification, the battery can has a bottom having a sealed portion on one side, an open portion having an open portion on the other side opposite the bottom, and a cylindrical sidewall. The cylindrical sidewall may have a main body portion corresponding to a portion where the electrode assembly is attached, and a beading portion and a crimping portion formed in other portions.

[0031] In this specification, the insulating coating layer is a thinly applied material containing a specific insulating component, and may be a plate, thin film, tape, etc. that insulates by being applied to a part having a polarity, being in contact with a part having a polarity, or being interposed in contact or spaced state between spaces having opposite polarities to prevent electrical contact or short circuit between opposite polarities.

[0032] In this specification, the term "pulled out" of an electrode tab refers to a state in which the separator is not protecting the first and / or second electrode tab. This may result in a short circuit due to contact between the pulled out or exposed tab and an electrode having a different polarity from the pulled out tab inside the battery can. The insulating coating layer according to an embodiment of the present invention can easily insulate, for example, between the first end of the pulled out first electrode tab and the second electrode having a different polarity, or between the second end of the pulled out second electrode tab and the first electrode having a different polarity.

[0033] In this specification, the battery can may be connected to the first electrode (or the first end) and serve as an electrode terminal.

[0034] In this specification, the battery can may refer to a cylindrical secondary battery in which a jelly roll-shaped electrode assembly is housed.

[0035] In one embodiment of the present specification, the secondary battery may be a cylindrical secondary battery having a form factor ratio (defined as the value obtained by dividing the diameter by the height of a cylindrical battery, i.e., the ratio of the height H to the diameter Φ) of greater than 0.4. Here, the form factor refers to a value indicating the diameter and height of a cylindrical secondary battery.

[0036] A cylindrical secondary battery according to an embodiment of the present specification may be a 46110 cell, a 48750 cell, a 48110 cell, a 48800 cell, or a 46800 cell. In the number representing the form factor, the first two digits represent the diameter of the cell, the next two digits represent the height of the cell, and the final digit 0 indicates that the cross section of the cell is circular.

[0037] The secondary battery according to one embodiment of the present specification may be a cylindrical secondary battery that is a cylindrical cell having a diameter of 46 mm, a height of 110 mm, and a form factor ratio of 0.418.

[0038] A secondary battery according to one embodiment of the present specification may be a cylindrical secondary battery that is a cylindrical cell having a diameter of 48 mm, a height of 75 mm, and a form factor ratio of 0.640.

[0039] The secondary battery according to one embodiment of the present specification may be a cylindrical secondary battery that is a cylindrical cell having a diameter of 48 mm, a height of 110 mm, and a form factor ratio of 0.418.

[0040] A secondary battery according to one embodiment of the present specification may be a cylindrical secondary battery that is a cylindrical cell having a diameter of 48 mm, a height of 80 mm, and a form factor ratio of 0.600.

[0041] A secondary battery according to one embodiment of the present specification may be a cylindrical secondary battery that is a cylindrical cell having a diameter of 46 mm, a height of 80 mm, and a form factor ratio of 0.575.

[0042] In this specification, the battery can is electrically connected to the first end, and the battery can includes an insulating coating layer formed on the inner surface corresponding to the second end, so that the battery can and the second end have opposite polarities, thereby preventing unwanted contact and / or short circuit between electrodes having opposite polarities.

[0043] According to an embodiment of the present invention, the sidewall of the battery can may further include an insulating coating layer formed on an inner surface corresponding to the separator.

[0044] According to one embodiment of the present invention, the second electrode includes a current collector; and an electrode active material layer provided on one or both sides of the current collector, and the second electrode tab may be a plain portion of the current collector where the electrode active material layer is not provided.

[0045] According to another embodiment of the present invention, the first electrode tab and / or the second electrode tab may be configured separately from the uncoated portion, and the first electrode tab and / or the second electrode tab may be connected to the uncoated portion by a method such as welding.

[0046] In this specification, the current collector may be referred to as the "current collector layer" and may be aluminum or the like for a positive electrode current collector and copper or the like for a negative electrode current collector depending on the polarity. However, any current collector known in the art may be used without limitation.

[0047] In this specification, the electrode active material layer may be formed by applying an electrode active material to one or both surfaces of the current collector.

[0048] In this specification, the type of electrode active material varies depending on the polarity. As the positive electrode active material, lithium-containing metal oxides such as LiCoO2 and LiMn2O5 may be mainly used, but any active material known in the art may be used without limitation. As the negative electrode active material, carbon-based materials, silicon-based materials, etc. are mainly used, but any active material known in the art may be used without limitation.

[0049] In this specification, the phrase "the electrode tab is the uncoated portion of the current collector where the electrode active material layer is not provided" means that the uncoated portion on the current collector serves as an electrode tab. However, if the uncoated portion comes into contact with an electrode having a polarity different from that of the uncoated portion, a short circuit may occur.

[0050] In this specification, an insulating coating layer is provided on the side wall of the battery can (for example, the first electrode) corresponding to the uncoated portion (for example, the uncoated portion of the second electrode), thereby preventing short circuits.

[0051] In this specification, the second electrode tab is a plain portion, and the plain portion may mean that a stripe pattern electrode is slit and a metal foil is formed to reduce cell resistance.

[0052] According to one embodiment of the present invention, the electrode tab may be bent toward the winding center or toward the outside of the electrode assembly.

[0053] According to one embodiment of the present invention, the battery may further include a second current collector plate electrically connected to the second electrode tab, and may further include an insulating member provided between the second current collector plate and a bottom of the battery can.

[0054] In this specification, the second electrode tab (or uncoated portion) may be welded to the second current collecting plate to be electrically connected thereto.

[0055] In this specification, an insulating member (e.g., an insulator) may be included between the second current collector plate and the bottom of the battery can. Here, the insulating member may have a straight shape instead of a conventional bent shape. This eliminates wasted space caused by the insulating member being bent, thereby increasing the space available for the electrode assembly.

[0056] In the secondary battery according to the above embodiment, the insulating member and the insulating coating layer are separately allocated to separate locations in comparison with the space occupied by the conventional insulating member (and insulating tape), thereby enabling the diameter of the electrode assembly that can be accommodated in a battery can of the same specification to be increased.

[0057] According to one embodiment of the present invention, the second end may be disposed adjacent to the bottom of the battery can.

[0058] According to an embodiment of the present invention, the battery may further include a second electrode terminal riveted through a through-hole formed in the bottom of the battery can.

[0059] In this specification, the rivet structure of the electrode terminal is formed by bending the upper surface of the electrode terminal so that the outer diameter of the portion of the electrode terminal exposed to the outside of the battery can is larger than the outer diameter of the through hole of the battery can. At this time, the portion of the gasket exposed to the outside of the battery can is also bent at the same angle as the electrode terminal during the pressing process. The outer diameter of the through hole refers to the diameter of the through hole.

[0060] According to one embodiment of the present invention, the battery may include a gasket interposed between the battery can and the second electrode terminal.

[0061] According to one embodiment of the present invention, the insulating coating layer may include, but is not limited to, one or more selected from alumina (Al2O3), aluminum nitride (AlN), magnesium oxide (MgO), boron nitride (BN), silicon carbide (SiC), and silicon nitride (Si3N4).

[0062] As described above, the insulating coating layer contains a highly heat-resistant material such as alumina, and when the temperature inside the battery rises to a high temperature, it exhibits excellent heat dissipation effects, maintains excellent insulating properties of the insulating coating layer, and effectively insulates between the second end of the electrode assembly and the battery can connected to the first end.

[0063] According to one embodiment of the present invention, the insulating coating layer may have a thickness of 200 μm or less.

[0064] According to one embodiment of the present invention, the thickness of the insulating coating layer may be more than 30 μm and not more than 200 μm.

[0065] According to one embodiment of the present invention, the thickness of the insulating coating layer may be greater than 30 μm, greater than 40 μm, or greater than 50 μm, or may be equal to or less than 200 μm, equal to or less than 190 μm, or equal to or less than 180 μm.

[0066] In this specification, when the thickness range of the insulating coating layer is satisfied, the diameter of the electrode assembly accommodated in the battery can can be increased.

[0067] In one embodiment of the present invention, the insulating member may have a thickness of more than 500 μm and not more than 1,500 μm.

[0068] According to one embodiment of the present invention, the thickness of the insulating member may be greater than 500 μm, greater than 600 μm, or greater than 700 μm.

[0069] According to one embodiment of the present invention, the insulating member may have a thickness of 1500 μm or less, 1400 μm or less, or 1300 μm or less.

[0070] In this specification, the thickness range of the insulating member as described above is significantly thicker than that of the insulating coating layer, and when this range is met, it is possible to effectively insulate between the battery can and the current collector plate of different polarities.

[0071] According to one embodiment of the present invention, the thickness of the insulating coating layer may be 0.45% or less of the diameter of the electrode assembly in a wound state.

[0072] According to one embodiment of the present invention, the thickness of the insulating coating layer may be 0.06% or more of the diameter of the electrode assembly in a wound state.

[0073] In this specification, when the thickness of the insulating coating layer satisfies the above range with respect to the diameter of the wound electrode assembly, the diameter of the electrode assembly accommodated in the battery can can be increased.

[0074] In one embodiment of the present specification, the first end may be located on the open side of the battery can.

[0075] In one embodiment of the present specification, the battery may further include a first current collector plate electrically connected to the first electrode tab.

[0076] In one embodiment of the present specification, the battery can further includes a seal for sealing an opening of the battery can, and the seal may include a cap plate and a sealing gasket. For example, the cap plate for sealing the opening of the battery can may be made of a non-polar metal material, and the insulating and elastic sealing gasket may be made of, but is not limited to, polypropylene, polybutylene terephthalate, polyfluoroethylene, etc.

[0077] In this specification, the first electrode tab (or uncoated portion) may be electrically connected to a first current collecting plate by welding. The first current collecting plate may be made of a conductive metal material such as aluminum, steel, nickel, etc., but is not limited to these.

[0078] In this specification, the battery can may include a crimping portion that extends and bends inside the battery can to wrap around and fix the edges of the sealing gasket and the cap plate in order to fix the seal.

[0079] In this specification, the battery can may include a beading portion press-fitted into the inside of the battery can in a region adjacent to the open end, which supports the edge of the seal, particularly the outer peripheral surface of the sealing gasket, when the seal is fixed by the crimping portion.

[0080] In this specification, at least a portion of the edge of the first current collecting plate that does not contact the first electrode tab (uncoated portion) may be interposed between the beading portion and the sealing gasket and fixed by the crimping portion. Optionally, at least a portion of the edge of the first current collecting plate may be fixed to an inner circumferential surface of the beading portion adjacent to the crimping portion by welding.

[0081] According to one embodiment of the present invention, the first electrode may be a negative electrode and the second electrode may be a positive electrode.

[0082] Another embodiment of the present invention provides a battery module and / or a battery pack including a secondary battery according to the above-described embodiment.

[0083] Yet another embodiment of the present invention provides a vehicle including one or more battery packs according to the above-described embodiments.

[0084] An embodiment of the present invention will now be described with reference to the drawings.

[0085] 1 shows a conventional secondary battery 100 in which an insulating member 3 (e.g., an insulator) having a thickness of about 1 mm (about 1000 μm) wraps around a battery can 1, a second electrode current collector plate 10, and a second electrode end 5 at the same time, and an additional insulating member such as insulating tape 4 wraps around the periphery of the second electrode end 5 one or more times to provide additional insulation. This type of insulation method not only complicates the battery assembly process, but also poses problems in that the insulating member occupies a large volume within the battery can, thereby reducing the volume occupied by the electrode assembly and resulting in reduced battery capacity.

[0086] 2 and 3 show a secondary battery according to one embodiment of the present invention, in which the side wall of the battery can 1 includes an insulating coating layer 7 provided on the inner surface corresponding to the second electrode end 5. The insulating coating layer 7 may be provided only on the inner surface corresponding to the second electrode end 5, as in FIG. 2. Alternatively, the insulating coating layer 7 may be further provided on the inner surface corresponding to the separator, including the inner surface corresponding to the second electrode end 5 (optionally, on the entire inner wall of the battery can 1), as in FIG. 3.

[0087] The secondary battery according to the above embodiment has the advantage of simplifying the manufacturing process, increasing the diameter of the electrode assembly, and increasing the battery capacity.

[0088] 4, a battery pack 200 according to an embodiment of the present invention includes an assembly of electrically connected secondary battery cells 201 and a pack housing 202 that accommodates the assembly. The cylindrical secondary battery cells 201 refer to the secondary battery according to the above-described embodiment.

[0089] In the drawings, for convenience of illustration, components such as bus bars for electrically connecting the secondary battery 201, a cooling unit, and external terminals are omitted.

[0090] The battery pack 200 may be installed in a vehicle. The vehicle may be, for example, an electric vehicle, a hybrid vehicle, or a plug-in hybrid vehicle. The vehicle may be a four-wheeled vehicle or a two-wheeled vehicle.

[0091] Fig. 5 is a diagram illustrating a vehicle including the battery pack 200 of Fig. 4. Referring to Fig. 5, a vehicle V according to an embodiment of the present specification includes the battery pack 200 according to an embodiment of the present specification. The vehicle V is operated by receiving power from the battery pack 200 according to an embodiment of the present specification. [Example]

[0092] In the following, preferred examples are presented to aid in understanding the present invention, but these examples are merely illustrative of the present description, and it will be apparent to those skilled in the art that various changes and modifications are possible within the scope and technical spirit of the present description. Such changes and modifications are naturally intended to fall within the scope of the appended claims.

[0093] [Comparative Example 1] A battery can having the outer diameter and thickness shown in Table 1 below was prepared. A folded insulator was provided at the bottom of the battery can, and although the thickness of the current collector plate is omitted, insulating tape was provided inside the insulator, assuming that the positive electrode end would be wound once with insulating tape. Therefore, the diameter of the electrode assembly (jelly roll) that could be accommodated in the battery can was as shown in Table 1. For reference, the diameter of the electrode assembly only takes into account the side edges of the battery can.

[0094] [Example 1] A battery can was prepared under the same conditions as in Comparative Example 1. A straight-line insulator was provided at the bottom of the battery can, and the thickness of the current collector plate was omitted. An insulating coating layer containing alumina was provided on the side wall of the battery can, and its thickness was as shown in Table 1. As a result, the diameter of the electrode assembly (jelly roll) that could be accommodated in the battery can was as shown in Table 1.

[0095] [Table 1]

[0096] As shown in Table 1, the diameter of the wound electrode assembly that can be accommodated in the battery can of Example 1 was larger than that of Comparative Example 1. Because Comparative Example 1 was designed to wrap the insulating tape only once, it is reasonably expected that the diameter of the wound electrode assembly of Comparative Example 1 would be smaller than that of Comparative Example 1 if the insulating tape were wrapped two or more times.

[0097] Although the present invention has been described above using limited examples and drawings, the present invention is not limited thereto, and it goes without saying that various modifications and variations can be made by a person having ordinary skill in the art to which the present invention pertains within the technical spirit of the present invention and the equivalent scope of the claims set forth below. [Explanation of symbols]

[0098] 1 Battery can 2...electrode assembly 3. Insulating material 4. Additional insulating material (insulating tape) 5...Second electrode end 6 First current collecting plate 7. Insulation coating layer 8...Second electrode terminal 9. Gasket 10 Second current collecting plate 11 Core portion of electrode assembly 100...Secondary battery 200 battery pack 201 Secondary battery cell V...Automotive

Claims

1. an electrode assembly in which a first electrode, a separator, and a second electrode are sequentially stacked and wound; a battery can containing the electrode assembly and an electrolyte; A secondary battery comprising: The battery can has a bottom on one side, an open portion on the other side opposite the bottom, and a cylindrical sidewall, the electrode assembly has a first end from which a tab of the first electrode is drawn out and a second end from which a tab of the second electrode is drawn out, the first end and the battery can are electrically connected; the sidewall of the battery can includes an insulating coating layer coated only on the inner surface corresponding to the second end; a second current collector plate electrically connected to the tab of the second electrode; a secondary battery including an insulating member provided between the second current collector plate and a bottom of the battery can.

2. The secondary battery of claim 1 , wherein the sidewall of the battery can further comprises an insulating coating layer formed on an inner surface corresponding to the separator.

3. the second electrode includes a current collector; and an electrode active material layer provided on one or both surfaces of the current collector, The secondary battery according to claim 1 , wherein the tab of the second electrode is a plain portion of the current collector on which the electrode active material layer is not provided.

4. The secondary battery according to claim 1 , wherein the second end is disposed adjacent to a bottom of the battery can.

5. The secondary battery according to claim 1 or 2, further comprising a second electrode terminal riveted through a through-hole formed in the bottom of the battery can.

6. The secondary battery according to claim 5 , further comprising a gasket interposed between the battery can and the second electrode terminal.

7. The insulating coating layer is made of alumina (Al ２ O ３ ), aluminum nitride (AlN), magnesium oxide (MgO), boron nitride (BN), silicon carbide (SiC) and silicon nitride (Si ３ N ４ 3. The secondary battery according to claim 1, comprising at least one selected from the group consisting of:

8. 3. The secondary battery according to claim 1, wherein the insulating coating layer has a thickness of 200 [mu]m or less.

9. The secondary battery according to claim 1 or 2, wherein the thickness of the insulating coating layer is more than 30 μm and not more than 200 μm.

10. The secondary battery according to claim 1 or 2, wherein the insulating member has a thickness of more than 500 μm and not more than 1,500 μm.

11. 3. The secondary battery according to claim 1, wherein the thickness of the insulating coating layer is 0.45% or less of the diameter of the wound electrode assembly.

12. The secondary battery of claim 1 , wherein the tab of the second electrode is bent toward a winding center or an outer periphery of the electrode assembly.

13. The secondary battery according to claim 1 , further comprising a cap plate that seals an open portion of the battery can.

14. The secondary battery according to claim 1 or 2, further comprising a first current collector plate electrically connected to a tab of the first electrode.

15. The battery further includes a seal that seals the open portion of the battery can. The secondary battery according to claim 1 , wherein the sealing body includes a cap plate and a sealing gasket.

16. The secondary battery according to claim 1 , wherein the first electrode is a negative electrode and the second electrode is a positive electrode.

17. A battery pack comprising at least one secondary battery according to claim 1 or 2.

18. 20. A motor vehicle comprising at least one battery pack according to claim 17.

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