Battery, battery pack comprising same, and vehicle comprising battery pack

Abstract

A battery according to one embodiment of the present invention may comprise: an electrode assembly; a battery housing for accommodating the electrode assembly through an opening formed at one side thereof; a battery terminal electrically connected to the electrode assembly through a closing part provided at the opposite side of the opening of the battery housing; and a current collector including a first coupling part, which is electrically coupled to the electrode assembly, and a second coupling part, which is electrically coupled to the battery terminal and has a resistance increase region formed in at least one portion thereof.

Description

Battery and battery pack including the same, and vehicle including the battery pack

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

[0002] This application claims priority to Korean Patent Application No. 10-2023-0110068, filed on August 22, 2023, and all contents disclosed in the specification and drawings of the said application are incorporated by reference into this application.

[0003] Current fuse devices used in secondary batteries include PTC thermistors (positive temperature coefficient thermistors) and TCOs (thermal cut-outs). However, PTC and TCOs have a drawback: their inherent resistance increases with repeated operation, increasing the overall resistance of the circuit.

[0004] In addition, all of the above-mentioned devices are operated by heat generation due to overcurrent. In other words, the above-mentioned devices are devices that operate to block the flow of current only when overcurrent is generated in the circuit current path due to overcharging, etc., and this causes the temperature to rise.

[0005] Therefore, in the case of the above-mentioned devices, they can only operate and block overcurrent after overheating has already created a safety hazard, and cannot immediately block overcurrent when a cause that could cause a temperature increase occurs. Even if the internal pressure increases due to an abnormal rise in temperature within the secondary battery, if the overcurrent blocking is not performed at an appropriate time, safety issues such as fire or explosion may occur.

[0006] In addition, since the above-mentioned devices operate simply based on temperature, they are difficult to use in secondary batteries that exhibit high output, such as battery packs used in automobiles. That is, in the case of automobile battery packs, a high c-rate is required, and accordingly, the amount of heat generated is bound to be high. However, devices such as PTC thermistors (positive temperature coefficient thermistors), TCOs (thermal cut-outs), and thermal fuses have the problem of operating too early when placed in such high-temperature environments.

[0007] Therefore, a secondary battery is needed that can be used in an environment where high current flows, and that has a structure that can cut off the current in advance when an event that could cause the temperature to rise (e.g., an increase in the internal pressure of the secondary battery) occurs before the temperature rises to a level that could cause a safety issue.

[0008] The present invention was created in consideration of the above-described problems, and its primary purpose is to enable rapid disconnection of electrical connection when an overcurrent exceeding a standard value occurs in a battery.

[0009] However, the technical problems to be solved by the present invention are not limited to the problems described above, and other problems not mentioned can be clearly understood by those skilled in the art from the description of the invention described below.

[0010] According to one embodiment of the present invention for solving the above-described problem, a battery may include: an electrode assembly; a battery housing configured to receive the electrode assembly through an opening formed on one side thereof; a battery terminal configured to be electrically connected to the electrode assembly through a closing portion provided on an opposite side of the opening portion of the battery housing; and a current collector including a first coupling portion configured to be electrically coupled to the electrode assembly and a second coupling portion configured to be electrically coupled to the battery terminal and having a resistance increasing region formed on at least a portion thereof.

[0011] The above resistance increasing region can be configured to have a smaller cross-sectional area compared to the remaining region of the second joint.

[0012] The above resistance increasing region may be configured to have a thinner thickness compared to the remaining region of the second joint.

[0013] The above resistance increase region may include a groove line formed on one or both sides of the second joint.

[0014] The above groove line may extend along the circumferential direction of the battery.

[0015] The above resistance increasing region may include a plurality of groove lines formed on one or both sides of the second joint. The plurality of groove lines may be arranged spaced apart from each other along the radial direction of the battery.

[0016] The plurality of groove lines may be arranged spaced apart from each other along the circumferential direction of the battery.

[0017] A welded portion may be provided in the area where the second connecting portion and the battery terminal are connected. The welded portion may be provided in an area where the resistance increasing region is not formed.

[0018] The above resistance increasing region can be configured to surround the weld.

[0019] The electrode assembly may have a structure in which a laminate including a first electrode, a second electrode, and a separator interposed between the first and second electrodes is wound. The resistance increasing region may be provided at a position corresponding to the inner side of a winding center hole formed by winding the electrode assembly.

[0020] The above battery may include a protective member configured to cover an inner wall surface of the winding center hole at an entrance side of the winding center hole facing the collector.

[0021] The first coupling portion and the second coupling portion of the above-described collector may be positioned spaced apart from each other along the radial direction of the battery.

[0022] The above-mentioned collector may include a rim portion positioned on the outer periphery of the first coupling portion and the second coupling portion; and a connecting portion configured to connect the rim portion and the second coupling portion.

[0023] A battery pack according to one embodiment of the present invention for solving the above-described problem includes a battery according to one embodiment of the present invention.

[0024] According to one embodiment of the present invention, a vehicle for solving the above-described problem includes a battery pack according to one embodiment of the present invention.

[0025] According to one aspect of the present invention, when an overcurrent exceeding a standard value occurs in a battery, the electrical connection can be quickly cut off, thereby ensuring safety in battery use.

[0026] However, the advantageous effects derived from the present invention are not limited to the above-described effects, and other advantageous effects not mentioned will be clearly understood by those skilled in the art from the description of the invention described below.

[0027] The following drawings attached to this specification illustrate preferred embodiments of the present invention, and together with the detailed description of the invention described below, serve to further understand the technical idea of ​​the present invention, and therefore, the present invention should not be interpreted as being limited to matters described in such drawings.

[0028] FIG. 1 is a drawing showing the structure of an upper portion of a battery according to one embodiment of the present invention.

[0029] FIG. 2 is a drawing showing a resistance increasing region provided in a current collector (first current collector) according to one embodiment of the present invention.

[0030] Figure 3 is a drawing showing a cross-section taken along line AA' of Figure 2.

[0031] Figures 4 and 5 are drawings showing exemplary forms of the resistance increasing region of the present invention.

[0032] FIG. 6 and FIG. 7 are drawings showing the positional relationship between a resistance increasing region provided in a current collector (first current collector) according to one embodiment of the present invention and a weld formed on the current collector.

[0033] Figure 8 is a drawing for explaining the formation location of the resistance increase region of the present invention.

[0034] Figure 9 is a drawing showing a battery to which the protective member of the present invention is applied.

[0035] Fig. 10 is a drawing showing an exemplary form of a collector (first collector) of the present invention.

[0036] FIG. 11 is a drawing showing the structure of a lower portion of a battery according to one embodiment of the present invention.

[0037] FIG. 12 is a drawing showing a battery pack according to one embodiment of the present invention.

[0038] FIG. 13 is a drawing showing a vehicle according to one embodiment of the present invention.

[0039] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Prior to this, it should be noted that the terms and words used in this specification and claims should not be interpreted as limited to their typical or dictionary meanings, and should be interpreted with meanings and concepts that conform to the technical spirit of the present invention based on the principle that the inventor can appropriately define the concept of the term to best explain his or her own invention. Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are only some of the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention. Therefore, it should be understood that various equivalents and modified examples may exist as of the time of this application.

[0040]

[0041] First, a battery (1) according to an embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a drawing showing the structure of the upper portion of a battery according to an embodiment of the present invention. FIG. 2 is a drawing showing a resistance increasing region provided in a current collector (first current collector) according to an embodiment of the present invention. FIG. 3 is a drawing showing a cross-section taken along line AA' of FIG. 2.

[0042] Referring to FIGS. 1 to 3, a battery (1) according to one embodiment of the present invention may include an electrode assembly (10), a battery housing (20), a battery terminal (30), and a current collector (first current collector) (40). The battery (1) may be a secondary battery configured to be chargeable and dischargeable. The battery (1) may be, for example, a cylindrical battery.

[0043] The electrode assembly (10) may include a first electrode having a first polarity, a second electrode having a second polarity opposite to the first polarity, and a separator interposed between the first electrode and the second electrode. The electrode assembly (10) may have a form in which a laminate including the first electrode, the second electrode, and the separator is wound in one direction. When the electrode assembly (10) has such a wound form, a winding center hole (10a) may be formed in a region that becomes the winding center.

[0044] The first electrode may include a first uncoated portion (11), which is a region where an electrode active material is not applied. The first uncoated portion (11) may extend from one end of the first electrode along the winding direction of the electrode assembly (10). Accordingly, the first uncoated portion (11) may be provided on a first surface that is approximately perpendicular to the outer circumferential surface of the electrode assembly (10).

[0045] The second electrode may include a second non-coated portion (12), which is a region where an electrode active material is not applied (see FIG. 11). The second non-coated portion (12) may extend from one end of the second electrode along the winding direction of the electrode assembly (10). Accordingly, the second non-coated portion (12) may be provided on a second surface (a surface located on the opposite side to the first surface) that is approximately perpendicular to the outer circumferential surface of the electrode assembly (10).

[0046] Although not specifically illustrated in the drawing, the first uncoated portion (11) and / or the second uncoated portion (12) may include a plurality of segments formed by being divided along the winding direction of the electrode assembly (10). These segments may be formed by notching the first uncoated portion (11) and / or the second uncoated portion (12) to a predetermined depth. The plurality of segments may be bent approximately along the radial direction of the electrode assembly (10). In this case, some of the segments adjacent to each other along the radial direction may overlap each other.

[0047] The battery housing (20) may be configured to accommodate an electrode assembly (10) through an opening formed on one side thereof. The battery housing (20) may have a closing portion formed on the opposite side of the opening portion. The battery housing (20) may include a conductive metal. The battery housing (20) may be electrically connected to a second electrode of the electrode assembly (10).

[0048] The battery terminal (30) may be configured to be electrically connected to the electrode assembly (10) through a closing portion provided on the opposite side of the opening portion of the battery housing (20). The battery terminal (30) may be electrically connected, for example, to a first electrode of the electrode assembly (10). In this case, the battery terminal (30) may function as a first terminal of the battery (1). The battery terminal (30) and the battery housing (20) may have opposite polarities, and in this case, a first sealing member (G1) may be provided between the battery housing (20) and the battery terminal (30) to prevent contact between these components and to secure sealing of the battery housing (20).

[0049] The battery terminal (30) may include a first portion (31) and a second portion (32). The first portion (31) may be configured to be electrically coupled to a current collector (40) on the inside of the battery housing (20). The first portion (31) may be provided at a position corresponding to a winding center hole (10a) of the electrode assembly (10). The second portion (32) may be exposed to the outside of the battery housing (20). The second portion (32) may be located at approximately the center of the closing portion of the battery housing (20). The battery terminal (30) may include a third portion (33) provided on the outside of the first portion (31). The third portion (33) may be riveted toward the closing portion of the battery housing (20) to fix the battery terminal (30) to the battery housing (20).

[0050] The current collector (40) may be configured to electrically connect the battery terminal (30) and the electrode assembly (10). The current collector (40) may be electrically connected to the first electrode of the electrode assembly (10). An insulator (IS) may be interposed between the current collector (40) and the inner surface of the closed portion of the battery housing (20) to prevent contact between the battery housing (20) and the current collector (40) having opposite polarities.

[0051] The current collector (40) may be disposed on a first surface of the electrode assembly (10). The current collector (40) may include a first coupling portion (41) and a second coupling portion (42). The first coupling portion (41) may be configured to be electrically coupled to the electrode assembly (10). The first coupling portion (41) may be coupled to the first uncoated portion (11) of the electrode assembly (10). The first coupling portion (41) may be coupled to a coupling surface formed by bending the first uncoated portion (11). At least a portion of the first coupling portion (41) may be coupled to the first uncoated portion (11) in a region where the number of overlapping layers of the segments of the first uncoated portion (11) is maximized. The second coupling portion (42) may be electrically coupled to the battery terminal (30). The second connecting portion (42) can be electrically connected to the first portion (31) of the battery terminal (30). The second connecting portion (42) can be welded to the first portion (31) of the battery terminal (30) by a welding tool inserted through the winding center hole (10a) of the electrode assembly (10) or by a laser irradiated through the winding center hole (10a).

[0052] Meanwhile, the second connecting portion (42) may have a resistance increasing region (40a) formed at least in a portion. The resistance increasing region (40a) may be located at least in a portion within an area where the battery terminal (30) and the current collector (40) are in contact with each other. The resistance increasing region (40a) may be configured to have a smaller cross-sectional area compared to the remaining area of ​​the second connecting portion (42). The resistance increasing region (40a) may be configured to have a thinner thickness, for example, compared to the remaining area of ​​the second connecting portion (42), as illustrated in FIG. 3.

[0053] In this way, the battery (1) of the present invention is configured to have a region where the resistance partially increases on the current collector (40), so that when an overcurrent occurs due to an abnormality in the battery (1), the overcurrent can be quickly cut off through a break in the current collector (40) itself and / or a break in the joint portion between the current collector (40) and the battery terminal (30).

[0054]

[0055] Next, various embodiments of the resistance increasing region (40a) of the present invention will be described with reference to FIGS. 4 and 5 along with FIGS. 1 to 3. FIGS. 4 and 5 are drawings showing a resistance increasing region provided in a current collector (first current collector) according to one embodiment of the present invention, and are drawings showing various embodiments of groove lines constituting the resistance increasing region.

[0056] Referring to FIGS. 4 and 5 along with FIGS. 1 to 3, the resistance increasing region (40a) may include a groove line (L) formed on one side or both sides of the second connecting portion (42) of the current collector (40). The groove line (L) may be formed at a predetermined depth on one side or both sides of the second connecting portion (42). The groove line (L) may extend along the circumferential direction of the battery (1). The groove line (L) may be provided in an approximately closed loop shape. The resistance region (40a) may include a plurality of groove lines (L). The plurality of groove lines (L) may be arranged to be spaced apart from each other along the circumferential direction of the battery. The plurality of groove lines (L) may be arranged to be spaced apart from each other along the radial direction of the battery (1).

[0057]

[0058] Next, the positional relationship between the resistance increasing region (40a) and the weld (W) of the present invention will be described with reference to FIGS. 6 and 7 along with FIGS. 1 to 3. FIGS. 6 and 7 are drawings showing the positional relationship between the resistance increasing region provided on a current collector (first current collector) according to one embodiment of the present invention and the weld formed on the current collector.

[0059] Referring to FIGS. 1 to 3, as well as FIGS. 6 and 7, a welding portion (W) may be provided in an area where the second joining portion (42) of the current collector (40) of the present invention and the battery terminal (30) are joined. The welding portion (W) may be provided in an area where the resistance increasing region (40a) is not formed. With this configuration, when welding is performed for joining the battery terminal (30) and the current collector (40), the groove line (L) forming the resistance increasing region (40a) can be prevented from melting and the cross-sectional area reducing region from being removed.

[0060] The above resistance increasing region (40a) may be configured to surround the weld (W). For example, when the resistance increasing region (40a) includes a groove line (L) having a substantially closed loop shape, the weld (W) may be located within a space surrounded by the groove line (L). In another aspect, the weld (W) may be located between adjacent groove lines (L) that are spaced apart from each other as illustrated in FIG. 7. When the weld (W) and the resistance increasing region (40a) are arranged in this manner, the current flowing from the battery terminal (30) through the current collector (40) to the electrode assembly (10) passes through the resistance increasing region (40a) in the current collector (40). Therefore, when an overcurrent occurs, a rapid rupture may occur in the resistance increasing region (40a), thereby improving the safety of use of the battery (1).

[0061]

[0062] Next, the relative positional relationship between the resistance increasing region (40a) of the present invention and the electrode assembly (10) will be described with reference to FIG. 8. FIG. 8 is a drawing for explaining the formation position of the resistance increasing region of the present invention.

[0063] Referring to Fig. 8, the resistance increasing region (40a) of the present invention may be located within an area corresponding to the inner side of the winding center hole (10a) formed by winding the electrode assembly (10). That is, the resistance increasing region (40a) may be arranged within an area indicated by an arrow in Fig. 8. According to this configuration, even if an overcurrent occurs during the use of the battery (1) and a rupture occurs in the resistance increasing region (40a) due to this, foreign matter caused by the rupture can fall through the winding center hole (10a), thereby minimizing the possibility of inflow into the interior of the electrode assembly (10).

[0064] Next, the protective member (50) of the present invention will be described with reference to Fig. 9. Fig. 9 is a drawing showing a battery to which the protective member of the present invention is applied.

[0065] Referring to FIG. 9, the battery (1) of the present invention may include a protective member (50) configured to cover the inner wall surface of the winding center hole (10a) at the entrance side of the winding center hole (10a) facing the current collector (40). When the battery (1) of the present invention is provided with the protective member (50) in this way, as described above, when a foreign substance generated when the resistance increasing region (40a) is broken enters the winding center hole (10a), the concern that the separator located on the inner wall surface of the winding center hole (10a) will be damaged by the foreign substance can be reduced.

[0066] The above protective member (50) may be configured to cover only a portion of the entire inner wall surface area of ​​the winding center hole (10a). The above protective member (50) may be configured to cover only an area adjacent to the current collector (40) among the entire inner wall surface area of ​​the winding center hole (10a). With such a configuration, the phenomenon of impregnation of the electrolyte through the inner wall surface of the winding center hole (10a) being hindered may be minimized.

[0067]

[0068] Next, with reference to Fig. 10, an exemplary form of the current collector (40) of the present invention will be described. Fig. 10 is a drawing showing an exemplary form of the current collector (first current collector) of the present invention.

[0069] Referring to Fig. 10, the current collector (40) of the present invention may have a structure in which the first coupling portion (41) and the second coupling portion (42) described above are spaced apart from each other in the radial direction. The current collector (40) of the present invention may include a rim portion (43) positioned on the outer periphery of the first coupling portion (41) and the second coupling portion (42). The current collector (40) may include a connecting portion (44) configured to connect the rim portion (43) and the second coupling portion (42). In this way, when the first coupling portion (41) and the second coupling portion (42) are not directly connected to each other but are indirectly connected through the rim portion (43), the impact applied to the battery (1) can be dispersed. That is, it is possible to minimize the impact applied to the weld of the first joint (41) from being transferred to the weld of the second joint (42), and it is also possible to minimize the impact applied to the weld of the second joint (42) from being transferred to the first joint (41).

[0070]

[0071] Next, with reference to FIG. 11, the lower structure of a battery (1) according to one embodiment of the present invention will be described. FIG. 11 is a drawing showing the lower portion structure of a battery according to one embodiment of the present invention.

[0072] Referring to FIG. 11, a battery (1) according to one embodiment of the present invention may include a current collector (second current collector) (60). The current collector (60) may be configured to electrically connect an electrode assembly (10) and a battery housing (20). The current collector (60) may be electrically connected to a second electrode of the electrode assembly (10). The current collector (60) may be electrically coupled to a second non-conductive portion (12) provided on a second surface of the electrode assembly (10). The current collector (60) may be electrically coupled to an inner surface of the battery housing (20). The current collector (60) may be electrically coupled to a beading portion (21) formed by press-fitting an outer peripheral surface of the battery housing (20).

[0073] The battery (1) may include a cap (70). The cap (70) may be configured to close an opening of the battery housing (20). The cap (70) may be secured by a crimping portion (22) configured to extend and bend from a beading portion (21) of the battery housing (20) and wrap around an edge of the cap (70). A sealing member (second sealing member) (G2) may be interposed between the cap (70) and an inner surface of the battery housing (20). The cap (70) may include a venting portion (71) configured to be weaker compared to the remaining area. The venting portion (71) may be configured to partially reduce the thickness of the cap (70). The venting portion (71) may be configured to be ruptured when the internal pressure of the battery (1) increases to a predetermined pressure or higher.

[0074]

[0075] Next, a battery pack (3) according to one embodiment of the present invention will be described with reference to FIG. 12. FIG. 12 is a drawing showing a battery pack according to one embodiment of the present invention.

[0076] Referring to FIG. 12 together with FIG. 1 and FIG. 11, a battery pack (3) according to an embodiment of the present invention may include a battery (1) according to an embodiment of the present invention and a pack housing (2) accommodating the battery (1). A plurality of batteries (1) may be provided, and the plurality of batteries (1) may be electrically connected to each other. The battery (1) of the present invention may be configured such that the battery terminal (30) and the closing portion of the battery housing (20) may function as a first electrode terminal and a second electrode terminal, respectively. Therefore, when arranging a plurality of batteries (1) within the pack housing (2), electrical connection can be made at the upper portion of the battery (1) by arranging the terminals (30) of all the batteries (1) so that they face upward.

[0077] Next, with reference to Fig. 13, a vehicle (5) according to one embodiment of the present invention will be described. Fig. 13 is a drawing showing a vehicle according to one embodiment of the present invention.

[0078] Referring to FIG. 13, a vehicle (5) according to one embodiment of the present invention may include a battery pack (3) according to one embodiment of the present invention. The vehicle (5) may be configured to operate by receiving power from the battery pack (3). The vehicle (5) may be, for example, an electric vehicle or a hybrid vehicle.

[0079]

[0080] Although the present invention has been described above with reference to limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical idea of ​​the present invention and the equivalent scope of the patent claims to be described below by a person having ordinary skill in the art to which the present invention pertains.

[0081] [Explanation of symbols]

[0082] 1: Battery

[0083] 2: Pack housing

[0084] 3: Battery pack

[0085] 5: Car

[0086] 10: Electrode assembly

[0087] 20: Battery housing

[0088] 30: Battery terminals

[0089] 40: Whole house (1st whole house)

[0090] 40a: Increased resistance zone

[0091] L: Groove line

[0092] 50: Absence of protection

Claims

1. Electrode assembly; A battery housing configured to accommodate the electrode assembly through an opening formed on one side; A battery terminal configured to be electrically connected to the electrode assembly through a closing portion provided on the opposite side of the opening portion of the battery housing; and A current collector comprising a first coupling portion configured to be electrically coupled with the electrode assembly and a second coupling portion configured to be electrically coupled with the battery terminal and having a resistance increasing region formed at least in a portion thereof; A battery containing .

2. In paragraph 1, The above resistance increase area is, A battery characterized in that it is configured to have a smaller cross-sectional area compared to the remaining area of ​​the second joint.

3. In paragraph 1, The above resistance increase area is, A battery characterized in that it is configured to have a thinner thickness compared to the remaining area of ​​the second joint.

4. In paragraph 1, The above resistance increase area is, A battery characterized by including a groove line formed on one or both sides of the second connecting portion.

5. In paragraph 4, The above groove line is, A battery characterized in that it extends along the circumference of the battery.

6. In paragraph 1, The above resistance increasing region includes a plurality of groove lines formed on one or both sides of the second joint, A battery characterized in that the plurality of groove lines are arranged spaced apart from each other along the radial direction of the battery.

7. In paragraph 1, The above resistance increasing region includes a plurality of groove lines formed on one or both sides of the second joint, A battery characterized in that the plurality of groove lines are arranged spaced apart from each other along the circumferential direction of the battery.

8. In paragraph 1, A welding part is provided in the area where the second connecting part and the battery terminal are connected, A battery characterized in that the above welding part is provided in an area where the above resistance increase area is not formed.

9. In paragraph 1, A welding part is provided in the area where the second connecting part and the battery terminal are connected, A battery characterized in that the resistance increasing region is configured to surround the welded portion.

10. In paragraph 1, The electrode assembly has a structure in which a laminate including a first electrode, a second electrode, and a separator interposed between the first electrode and the second electrode is wound, A battery characterized in that the above resistance increase region is provided at a position corresponding to the inner side of a winding center hole formed according to the winding of the electrode assembly.

11. In paragraph 10, The above battery, A battery characterized in that it includes a protective member configured to cover the inner wall surface of the winding center hole on the entrance side of the winding center hole facing the entire body.

12. In paragraph 1, A battery characterized in that the first coupling portion and the second coupling portion of the above-mentioned collector are positioned spaced apart from each other along the radial direction of the battery.

13. In paragraph 11, The above-mentioned entire house, A rim portion located on the outer periphery of the first connecting portion and the second connecting portion; and A connecting portion configured to connect the rim portion and the second connecting portion; A battery characterized by including:

14. A battery pack comprising a battery according to any one of claims 1 to 13.

15. A vehicle including a battery pack according to Article 14.

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