Battery cell comprising current blocking part and battery device comprising battery cell

Abstract

The cell according to an embodiment of the present invention may comprise: an electrode assembly in which at least one positive plate and at least one negative plate are stacked on each other; a case accommodating the electrode assembly therein; a plurality of electrode tabs extending from the positive plate and the negative plate, respectively; an electrode lead having one end joined to the electrode tab and the other end extending to the outside of the case; and a current blocking part which is provided inside the electrode lead and blocks the flow of an overcurrent, the length of the current blocking part in the extending direction of the electrode lead being 1 / 10 or less of the length of the electrode lead.

Description

Technical Field

[0001] The present invention relates to a battery cell including a current interruption portion and a battery device including the battery cell. Background Art

[0002] Unlike primary batteries, secondary batteries can be charged and discharged, so secondary batteries can be applied to various fields such as digital cameras, mobile phones, notebook computers, hybrid vehicles. Secondary batteries can include nickel-cadmium batteries, nickel-metal hydride batteries, nickel-hydrogen batteries, lithium secondary batteries, etc.

[0003] Among these secondary batteries, research on lithium secondary batteries with high energy density and discharge voltage is actively underway. In recent years, lithium secondary batteries have been used in the form of battery modules or battery packs that connect multiple flexible pouch-type cells. The electrode leads of multiple cells in a battery module or battery pack are connected in series or in parallel with each other. Therefore, when a dangerous situation occurs in any one cell, a chain reaction may occur in all electrically connected cells, and there is a possibility that the dangerous situation will also spread.

[0004] Therefore, there is a need for a method of preventing an overcurrent from flowing into other cells even if an overcurrent occurs in any one cell due to a short circuit or the like. Summary of the invention

[0005] 1. Technical issues to be resolved

[0006] An object of the present invention is to provide a battery cell and a battery device including the battery cell that can improve stability by blocking the flow of an overcurrent.

[0007] (II) Technical solution

[0008] According to an embodiment of the present invention, a battery cell may include: an electrode assembly, which is formed by stacking at least one positive electrode plate and at least one negative electrode plate; a shell, which accommodates the electrode assembly; a plurality of electrode tabs, which extend from the positive electrode plate and the negative electrode plate, respectively; an electrode lead, one end of which is joined to the electrode tab and the other end of which extends to the outside of the shell; and a current blocking portion, which is arranged inside the electrode lead to block the flow of excess current, and the length of the current blocking portion in the extension direction of the electrode lead may be less than 1 / 10 of the length of the electrode lead.

[0009] In this embodiment, the current blocking portion may be formed of a material that melts at a temperature ranging from 150° C. to 185° C.

[0010] In this embodiment, the current blocking portion may be formed of a material having a resistivity of 0.2 μΩ·m or less.

[0011] In this embodiment, the current blocking portion may be formed of a material having a thermal conductivity of 40 W / m·K or more.

[0012] In this embodiment, the current blocking portion can be made of a material having a tensile strength of 100 kgf / cm 2 The above materials are formed.

[0013] In this embodiment, the current blocking portion may be formed of an alloy material including tin (Sn).

[0014] In this embodiment, the current blocking portion may be formed of any one material selected from tin / lead, tin / lead / silver, tin / indium / silver, and tin / lead / indium.

[0015] In this embodiment, the tin / lead may be an alloy consisting of 60-65 weight % tin (Sn) and 35-40 weight % lead (Pb), the tin / lead / silver may be an alloy in which 1-2 weight % silver (Ag) is added to the tin / lead, the tin / indium / silver may be an alloy consisting of 75-80 weight % tin (Sn), 18-22 weight % indium (In) and 1-5 weight % silver (Ag), and the tin / lead / indium may be an alloy consisting of 68-72 weight % tin (Sn), 15-20 weight % lead (Pb) and 10-15 weight % indium (In).

[0016] In this embodiment, the current blocking portion may be formed of any one material selected from Sn63 / Pb37, Sn62.5 / Pb36.1 / Ag1.4, Sn60 / Pb40, Sn77.2 / In20 / Ag2.8, and Sn70 / Pb18 / In12.

[0017] In this embodiment, the electrode lead may include: a first lead disposed between the current blocking portion and the electrode tab; and a second lead disposed at an opposite side of the first lead.

[0018] In this embodiment, the electrode lead may be a negative electrode lead connected to the negative electrode plate.

[0019] In this embodiment, the electrode lead may be formed of copper (Cu) material.

[0020] In addition, the battery cell according to an embodiment of the present invention may include: an electrode assembly, in which at least one positive electrode plate and at least one negative electrode plate are stacked on each other; a shell, in which the electrode assembly is housed; a plurality of electrode tabs, extending from the positive electrode plate and the negative electrode plate, respectively; an electrode lead, one end of which is joined to the electrode tab and the other end of which extends to the outside of the shell; and a current blocking portion, which is arranged inside the electrode lead to block the flow of overcurrent, and the current blocking portion may be made of a material that melts within the range of 150°C-185°C, has a resistivity of less than 0.2μΩ·m, and a tensile strength of 100kgf / cm 2 The above materials are formed.

[0021] In addition, a battery device according to an embodiment of the present invention may include: a plurality of battery cells, including a shell for accommodating an electrode assembly and an electrode lead extending from the electrode assembly and at least partially arranged on the outside of the shell; and a bus bar, which is combined with the electrode lead, and a current blocking portion for blocking the flow of an overcurrent may be arranged inside the electrode lead, and the current blocking portion may be separated from the bus bar by a predetermined distance.

[0022] In this embodiment, the current blocking portion may be formed of a material that melts within a temperature range of 150° C. to 185° C.

[0023] (III) Beneficial effects

[0024] The battery cell according to the embodiment of the present invention includes a current blocking portion in the electrode lead, so even if an abnormal phenomenon such as high temperature or overcurrent occurs in the battery cell, the flow of current can be quickly blocked. Therefore, it is possible to suppress the abnormal phenomenon from spreading to other battery cells or affecting the battery device. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a perspective view schematically showing a battery cell according to an embodiment of the present invention.

[0026] Figure 2 yes Figure 1 Exploded three-dimensional diagram.

[0027] Figure 3 is along Figure 1 A cross-sectional view taken along line II'.

[0028] Figure 4 It is schematically shown that Figure 1 A three-dimensional diagram of a battery device with a battery cell.

[0029] Figure 5 yes Figure 4 Exploded three-dimensional diagram.

[0030] Figure 6 is along Figure 4A cross-sectional view taken along line II-II'. DETAILED DESCRIPTION

[0031] Before describing the present invention in detail, it should be noted that the terms or words used in the present specification and claims described below should not be interpreted as limited to the general meaning or the meaning in the dictionary, but should be interpreted as the meaning and concept that conforms to the technical idea of ​​the present invention based on the principle that the inventor can appropriately define the terms in order to explain his own invention in the best way. Therefore, it should be understood that the embodiments recorded in this specification and the structures shown in the drawings are only the most preferred embodiments of the present invention, and do not represent all the technical ideas of the present invention, and may include various equivalents and modifications that can replace them when submitting this application.

[0032] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. At this time, in the accompanying drawings, the same components are represented by the same reference numerals as much as possible. In addition, detailed descriptions of well-known functions and structures that may confuse the gist of the present invention are omitted. For the same reason, some components in the accompanying drawings are enlarged, omitted or schematically shown, and the size of each component does not fully reflect the actual size.

[0033] Figure 1 is a perspective view schematically showing a battery cell according to an embodiment of the present invention, Figure 2 yes Figure 1 The exploded perspective view of the battery cell shown, Figure 3 is along Figure 1 A cross-sectional view taken along line II'.

[0034] Reference Figures 1 to 3 The battery cell 100 according to the present embodiment may include an electrode assembly 130 , a case 110 accommodating the electrode assembly 130 , and a protective film 40 .

[0035] The battery cell 100 according to the present embodiment is a secondary battery that can be charged and discharged, and may include a lithium ion (Li-ion) battery or a nickel metal hydride (Ni-MH) battery. The nickel metal hydride battery is a secondary battery that uses nickel for the positive electrode, a hydrogen absorption alloy for the negative electrode, and an alkaline aqueous solution for the electrolyte, and has a large capacity per unit volume, so the nickel metal hydride battery can be used not only as an energy source such as an electric vehicle (EV) or a hybrid electric vehicle (HEV), but also in various fields such as energy storage purposes.

[0036] The battery cell 100 may have a pouched type structure. For example, the case 110 may be used by insulating the surface of a metal layer made of aluminum. The insulating treatment may be formed by coating a surface of the metal layer with modified polypropylene as a polymer resin and laminating a resin material such as nylon or polyethylene terephthalate (PET) on its outer side.

[0037] The case 110 may be provided at an inner side thereof with a receiving space 113 receiving the electrode assembly 130 . Also, the electrode lead 120 may protrude to an outer side of the case 110 .

[0038] like Figure 2 As shown, the battery cell 100 of this embodiment can seal the accommodation space 113 by folding a sheet of outer packaging material and joining three sides. Therefore, the housing 110 of this embodiment can be divided into a first housing 110a and a second housing 110b based on the bending line C of the folded outer packaging material.

[0039] Specifically, the battery cell 100 of this embodiment can be manufactured by accommodating the electrode assembly 130 in the accommodating space 113 , folding the outer packaging material along the bending line C, and then joining the edges of the first shell 110 a and the second shell 110 b to seal the accommodating space 113 .

[0040] As a method for joining the edges, heat welding may be used, but the method is not limited thereto. Hereinafter, the joined edge portion is referred to as a sealing portion 115 .

[0041] In the present embodiment, the sealing portion 115 may be divided into a first sealing portion 115 a formed at a portion where the electrode lead 120 is provided and a second sealing portion 115 b formed at a portion where the electrode lead 120 is not provided.

[0042] The sealing portion 115 may be formed in a flange shape extending from the receiving space 113 to the outside. Therefore, the sealing portion 115 may be disposed along the periphery of the receiving space 113 .

[0043] On the other hand, in this embodiment, the case of manufacturing the battery cell by folding the outer packaging material is described as an example, but it is not limited thereto, and the first shell 110a and the second shell 110b can also be formed by separate outer packaging materials. In this case, the sealing part 115 can be provided on four sides of the accommodation space 113.

[0044] In addition, in the battery cell 100 of this embodiment, the first shell 110a and the second shell 110b may be provided with a receiving space 113. However, the present invention is not limited thereto, and various changes may be made, for example, the receiving space 113 may be provided in only one of the first shell 110a and the second shell 110b.

[0045] The electrode assembly 130 may be accommodated together with the electrolyte in the internal accommodation space 113 of the housing 110. The electrode assembly 130 may include: a plurality of electrodes 131a, 131b, divided into a positive electrode plate 131a and a negative electrode plate 131b; and a separator 132, disposed between the positive electrode plate 131a and the negative electrode plate 131a to electrically / physically isolate the positive electrode plate 131a from the negative electrode plate 131b.

[0046] The electrodes 131a and 131b may be formed by coating a positive electrode active material or a negative electrode active material on one or both surfaces of a metal film. In addition, the electrode assembly 130 may be configured in a form in which a plurality of positive electrode plates 131a and a plurality of negative electrode plates 131b are alternately stacked.

[0047] Electrode tabs 135 may be disposed between the electrode assembly 130 and the sealing portion 115. The electrode tabs 135 may include a positive electrode tab 135a extending from the positive electrode plate 131a and a negative electrode tab 135b extending from the negative electrode plate 131b.

[0048] The electrode tab 135 can be accommodated on the terrace (terrace) ( Figure 3 In the present embodiment, the platform 150 may correspond to the periphery of the portion of the housing 110 that accommodates the electrode assembly 130. In addition, the platform 150 may be defined as a portion of the housing 110 that corresponds to between the electrode assembly 130 and the sealing portion 115.

[0049] In this embodiment, the electrode tab 135 is led out from the first sealing portion 115a. Therefore, the platform 150 of this embodiment may include a region between the electrode assembly 130 and the first sealing portion 115a.

[0050] However, even if the electrode tab 135 is not accommodated, any empty space formed between the electrode assembly 130 and the sealing portion 115 or a portion where the battery cells 100 are not pressurized (or contacted) when the battery cells are stacked may be included in the platform 150. For example, the platform 150 may include a section where the thickness of the battery cell 100 gradually decreases toward the sealing portion 115.

[0051] The electrode lead 120 can electrically connect the battery cell 100 to other external devices. One end of the electrode lead 120 can be bonded to the electrode tab 135 to be electrically connected to the electrode assembly 130, and the other end of the electrode lead 120 can extend in the X-axis direction and be exposed to the outside of the housing 110.

[0052] The electrode lead 120 may include a positive electrode lead 120 a bonded to the positive electrode tab 135 a and a negative electrode lead 120 b bonded to the negative electrode tab 135 b .

[0053] The positive electrode lead 120 a and the negative electrode lead 120 b may be made of metal in the form of a thin plate. For example, the positive electrode lead 120 a may be made of an aluminum (Al) material, and the negative electrode lead 120 b may be made of a copper (Cu) material, but the present invention is not limited thereto.

[0054] In the present embodiment, the positive electrode lead 120a and the negative electrode lead 120b are arranged to face in opposite directions to each other, so the positive electrode lead 120a and the negative electrode lead 120b protrude from both sides of the housing 110. However, the configuration of the present invention is not limited thereto, and various changes can be made as needed, for example, the positive electrode lead 120a and the negative electrode lead 120b are arranged to face in the same direction.

[0055] The battery cell 100 configured in this way may experience abnormal conditions such as swelling, electrode short circuit, overcharge, over discharge, overheating, surge current, overcurrent, electrode short circuit, etc. during operation, which may cause the battery cell 100 to explode or catch fire.

[0056] Therefore, in order to prevent the above problem, the battery cell 100 of the present embodiment may include at least one current blocking portion 140 .

[0057] When the above abnormal situation occurs and the temperature of the battery cell 100 increases, the current blocking portion 140 may block the electrical connection between the battery cell 100 and another battery cell 100 .

[0058] When the battery cell 100 operates normally, the internal temperature of the battery cell 100 can rise to nearly 120°C. It is confirmed that when the temperature of the battery cell 100 exceeds 190°C, the battery cell 100 explodes or generates flames, etc., thereby causing thermal runaway. Therefore, in order to prevent thermal runaway, it is necessary to block the flow of current between the battery cells 100 before the internal temperature of the battery cell 100 exceeds 190°C.

[0059] Therefore, when the internal temperature of the battery cell 100 is within the range of 120°C to 190°C, the battery cell 100 of the present embodiment can block the electrical connection between the battery cell 100 and other components. More specifically, considering the temperature deviation between the electrode assembly 130 and the electrode lead 120, the current blocking portion 140 of the present embodiment can block the electrical connection between the battery cell 100 and external components when the internal temperature of the battery cell 100 is within the range of 150°C to 185°C, and thus the current blocking portion 140 can be formed of a material that can be rapidly melted within the temperature range of 150°C to 185°C.

[0060] The current blocking portion 140 may be provided in at least one of the positive lead 120a and the negative lead 120b. Since the thermal conductivity of the negative lead 120b formed of copper (Cu) is higher than the thermal conductivity of the positive lead 120a formed of aluminum, the temperature change may appear faster. Therefore, the current blocking portion 140 of the present embodiment is provided in the negative lead 120b to quickly sense the temperature change of the battery cell 100. However, various changes may be made as needed, for example, the current blocking portion 140 may be provided in the negative lead 120b and the positive lead 120a, respectively, or the current blocking portion 140 may be provided only in the positive lead 120a.

[0061] In addition, the current blocking portion 140 may be arranged in a form that spans the electrode lead 120. Specifically, the negative electrode lead 120b may be divided into a first lead 121 and a second lead 122 that are spaced apart from each other by the current blocking portion 140, and the first lead 121 and the second lead 122 may be respectively joined to both sides of the current blocking portion 140. For example, the first lead 121 may be arranged between the current blocking portion 140 and the electrode tab 135, and the second lead 122 may be arranged outside the current blocking portion 140 and joined to a bus bar (170 of FIG. 7 ) to be described later. Therefore, the first lead 121 and the second lead 122 may be electrically / physically connected to each other by the current blocking portion 140, and the separation distance between the first lead 121 and the second lead 122 may be determined by the current blocking portion 140.

[0062] Like the electrode lead 120 , the current blocking part 140 may be formed of a conductive material, and may be formed with the same or similar thickness as the electrode lead 120 .

[0063] In addition, refer to Figure 3 , the length (or width) W3 of the current blocking portion 140 in the extension direction (X direction) of the electrode lead 120 may be less than about 1 / 10 of the total length of the electrode lead 120 excluding the current blocking portion 140. Here, based on the battery cell, the total length of the electrode lead 120 may be defined as the sum of the length W1 of the first lead 121 and the length W2 of the second lead 122. In the present embodiment, the length of the current blocking portion 140 is a configuration derived in consideration of the resistivity of the current blocking portion 140 to be described later.

[0064] In addition, when the length of the current blocking portion 140 is less than 0.1 mm, the interval between the first lead 121 and the second lead 122 is too narrow, so even if the current blocking portion 140 is melted, the first lead 121 and the second lead 122 may be electrically connected. Therefore, the length of the current blocking portion 140 of this embodiment can be greater than 0.1 mm.

[0065] For example, when the total length (W1+W2) of the negative electrode lead 120b is 60 mm, the length W3 of the current blocking portion 140 may be 6 mm or less. Therefore, in this case, the first lead 121 and the second lead 122 may be spaced apart at an interval of 6 mm or less. However, the configuration of the present invention is not limited thereto.

[0066] Since the current blocking portion 140 is located inside the negative lead 120 b, when the battery cell 100 operates normally, the current blocking portion 140 is used as a path for current flow like the negative lead 120 b. Therefore, when the electric resistance of the current blocking portion 140 is relatively large, the current blocking portion 140 may become a factor that hinders the flow of current.

[0067] To this end, the current blocking portion 140 of the present embodiment may have a resistance value similar to the total resistance of the negative electrode lead 120b. Specifically, in the present embodiment, the current blocking portion 140 may be formed of a material having an electric resistivity (Electric resistivity) that is 10 times or less than the electric resistivity of the electrode lead 120. For example, when the negative electrode lead 120b is formed of a copper material, since the electric resistivity of copper (Cu) is about 0.02 μΩ·m, the current blocking portion 140 may be formed of a material having an electric resistivity of about 0.2 μΩ·m or less.

[0068] As described above, since the length W3 of the current blocking portion 140 of the present embodiment is approximately 1 / 10 of the length (W1+W2) of the negative electrode lead 120 b, and since the resistance is proportional to the length, if the current blocking portion 140 is formed of a material having a resistivity of approximately 0.2 μΩ·m or less, the total resistance of the current blocking portion 140 can have a resistance value similar to the total resistance of the negative electrode lead 120 b.

[0069] In this case, the total resistance of the current blocking portion 140 and the negative electrode lead 120b can be regarded as equivalent to the case where the length of the negative electrode lead 120b is extended to twice, so even if the current blocking portion 140 of this embodiment is included, the flow of current will not be significantly hindered. Therefore, considering the smooth flow of current, the length of the current blocking portion 140 of this embodiment can be about 1 / 10 of the length (W1+W2) of the electrode lead 120.

[0070] In addition, the thermal conductivity of copper (Cu) forming the negative electrode lead 120b is about 400 W / m·K. Therefore, it is advantageous to use a material having a thermal conductivity similar to that of the negative electrode lead 120b for the current blocking portion 140, but in this case, there is a problem of increasing the melting point of the current blocking portion 140. Therefore, in the present embodiment, the current blocking portion 140 is formed of a material having a thermal conductivity lower than that of the negative electrode lead 120b and 1 / 10 or more of the thermal conductivity of the negative electrode lead 120b, that is, a material having a thermal conductivity of 40 W / m·K or more.

[0071] In this case, although the thermal conductivity of the current blocking portion 140 is lower than that of the negative electrode lead 120 b, the resistivity of the current blocking portion 140 is higher than that of the negative electrode lead 120 b. Therefore, for the same current, heat may be generated faster in the current blocking portion 140 than in the negative electrode lead 120 b. Therefore, when an overcurrent flows, the current blocking portion 140 may reach a critical temperature faster and melt.

[0072] When the thermal conductivity of the current blocking portion 140 is less than 40 W / m·K, the timing of melting of the current blocking portion 140 may be erroneous due to the low thermal conductivity. That is, the interior of the battery cell 100 may reach a thermal runaway temperature before the current blocking portion 140 melts.

[0073] Therefore, in the present embodiment, the current blocking portion 140 may be formed of a material having a thermal conductivity of 40 W / m·K or more.

[0074] On the other hand, it is advantageous for the current blocking portion 140 to have a predetermined level of rigidity in order to maintain the overall shape of the negative electrode lead 120 b. 2 When the material rigidity is low, the current blocking portion 140 may be bent. Therefore, in this embodiment, the current blocking portion 140 may be made of a material with a tensile strength of 100 kgf / cm 2 The above materials are formed.

[0075] Therefore, the current blocking portion 140 of the present embodiment can be made of a material with a melting point in the range of 150°C-185°C, a resistivity of less than 0.2μΩ·m, a thermal conductivity of more than 40W / m·K, and a tensile strength of 100kgf / cm 2 The above materials are formed.

[0076] [Table 1]

[0077]

[0078] Various embodiments and comparative examples of the materials of the current blocking portion according to the present embodiment are listed in Table 1. Embodiments 1 to 5 represent materials that meet the above conditions, and Comparative Examples 1 to 7 represent materials that do not meet at least one of the above conditions. Here, the tensile strength represents a value measured according to ISO 6892-1, which is an international standard for tensile testing of metal materials.

[0079] Referring to Table 1, suitable materials for the current blocking part 140 according to the present embodiment may include Sn63 / Pb37, Sn62.5 / Pb36.1 / Ag1.4, Sn60 / Pb40, Sn77.2 / In20 / Ag2.8, Sn70 / Pb18 / In12, etc. disclosed in Embodiments 1 to 5. Here, the numbers represent weight % of the corresponding elements.

[0080] Since Sn63 / Pb37, Sn62.5 / Pb36.1 / Ag1.4, Sn60 / Pb40, Sn77.2 / In20 / Ag2.8, Sn70 / Pb18 / In12, etc. have melting points within the range of 150°C to 185°C, they can be used as the material of the current blocking portion 140. On the other hand, since Sn70 / Pb18 / In12, Sn91 / Zn09, etc. disclosed in Comparative Examples 1 and 2 have melting points above 200°C, they are difficult to be used as the material of the current blocking portion 140 of this embodiment.

[0081] In addition, the resistivity of Sn63 / Pb37, Sn62.5 / Pb36.1 / Ag1.4, Sn60 / Pb40, Sn77.2 / In20 / Ag2.8, Sn70 / Pb18 / In12, etc. disclosed in Examples 1 to 5 is less than 0.2 μΩ·m, and the thermal conductivity is greater than 40 W / m·K, but the resistivity in Comparative Examples 5 and 6 exceeds 0.2 μΩ·m, and the thermal conductivity in Comparative Examples 2 to 6 is less than 40 W / m·K, so it is difficult to be suitable as a material for the current blocking portion 140 of this embodiment.

[0082] In addition, the melting point, resistivity, and thermal conductivity of pure indium in Comparative Example 7 all meet the above conditions, but the tensile strength is less than 100 kgf / cm 2 , and therefore it is difficult to be suitable as the material of the current blocking portion 140 of this embodiment.

[0083] Therefore, the current blocking part 140 according to the present embodiment may be formed of any one of the materials Sn63 / Pb37, Sn62.5 / Pb36.1 / Ag1.4, Sn60 / Pb40, Sn77.2 / In20 / Ag2.8, and Sn70 / Pb18 / In12 disclosed in Embodiments 1 to 5.

[0084] The materials of Embodiments 1 to 5 may be formed of a low melting point metal having a melting point lower than that of tin (Sn). Specifically, the current blocking part 140 may have tin (Sn) as a main element and may further contain at least one element to lower the melting point.

[0085] As an example, the current blocking portion may further include at least one element of lead (Pb), silver (Ag), and indium (In). Specifically, the current blocking portion of this embodiment may be any one selected from tin / lead, tin / lead / silver, tin / indium / silver, and an alloy of tin / lead / indium.

[0086] Here, the tin / lead alloy may be an alloy composed of 60-65 wt% of tin (Sn) and 35-40 wt% of lead (Pb), and the tin / lead / silver alloy may be an alloy in which 1-2 wt% of silver (Ag) is added to the tin / lead alloy. In addition, the tin / indium / silver alloy may be an alloy composed of 75-80 wt% of tin (Sn), 18-22 wt% of indium (In) and 1-5 wt% of silver (Ag), and the tin / lead / indium alloy may be an alloy composed of 68-72 wt% of tin (Sn), 15-20 wt% of lead (Pb) and 10-15 wt% of indium (In).

[0087] Since the battery cell 100 of the present embodiment includes the current blocking portion 140 in the electrode lead 120, the current flow can be quickly blocked even if abnormal phenomena such as high temperature and overcurrent occur in the battery cell 100. Therefore, the abnormal phenomena can be prevented from spreading to other battery cells 100 or affecting the battery device.

[0088] In addition, the current blocking portion 140 of the present embodiment can be bonded to the first lead 121 and the second lead 122 only by a process of solidification after melting in a state of contact with the first lead 121 and the second lead 122. Therefore, in the process of bonding the current blocking portion 140 to the electrode lead 120, the electrode lead 120 does not melt or deform, and thus the resistance of the bonding portion can be minimized.

[0089] On the other hand, the present invention is not limited to the above-described embodiments, and various modifications can be made.

[0090] Figure 4 It is schematically shown that Figure 1 A three-dimensional diagram of a battery device with a cell, Figure 5 yes Figure 4 Exploded stereogram of Figure 6 is along Figure 4 A cross-sectional view taken along line II-II'.

[0091] Reference Figures 4 to 6The battery device 200 of the present embodiment may include a battery cell stack 1 in which a plurality of the battery cells 100 are stacked and a bus bar 170 .

[0092] The cell stack 1 may be formed by stacking a plurality of battery cells 100 in a thickness direction of the battery cells 100 .

[0093] The bus bar 170 may be formed in the form of a metal plate and disposed to face one side of the cell stack 1. Here, the one side of the cell stack 1 may refer to a side surface where the electrode lead 120 is disposed.

[0094] The electrode lead 120 may be coupled to the bus bar 170 . Therefore, the battery cells 100 may be electrically connected to each other through the bus bar 170 .

[0095] To this end, the bus bar 170 may be provided with a plurality of through holes 171, in which the electrode lead 120 is inserted and disposed, and the electrode lead 120 may be inserted into the through holes 171 of the bus bar 170 and then joined to the bus bar 170 by welding or the like. Therefore, at least a portion of the end of the electrode lead 120 may completely pass through the bus bar 170 and be exposed to the outside of the bus bar 170.

[0096] In addition, in the battery device 200 of the present embodiment, the current blocking portion 140 may be disposed at a predetermined distance from the bus bar 70. If the current blocking portion 140 is disposed in the through hole 171 of the bus bar 170, even if the current blocking portion 140 is melted, the contact between the electrode lead 120 and the bus bar 170 may be maintained, in which case the flow of current may be maintained, thereby causing the above-mentioned abnormal situation. Therefore, in the battery device 200 of the present embodiment, the current blocking portion 140 may be separated from the through hole 171 of the bus bar 170 and located outside the through hole 171.

[0097] The embodiments of the present invention are described in detail above, but the scope of the present invention is not limited thereto. It is obvious to those skilled in the art that various modifications and changes can be made without departing from the technical concept of the present invention.

[0098] For example, although the above embodiments are described by taking the case where the cooling device is disposed outside the first plate as an example, various changes may be made, for example, the cooling device is disposed inside the first plate, or the first plate includes a cooling channel. In addition, various embodiments may be implemented in combination with each other.

Claims

1. A battery cell, comprising: An electrode assembly, comprising at least one positive electrode plate and at least one negative electrode plate stacked on each other; A shell, the electrode assembly is accommodated therein; A plurality of electrode tabs extending from the positive electrode plate and the negative electrode plate respectively; an electrode lead, one end of which is joined to the electrode tab and the other end of which extends to the outside of the shell; as well as The current blocking portion is arranged inside the electrode lead to block the flow of excess current. The length of the current blocking portion in the extending direction of the electrode lead is 1 / 10 or less of the length of the electrode lead.

2. The battery cell according to claim 1, wherein: The current blocking portion is formed of a material that melts at a temperature ranging from 150° C. to 185° C.

3. The battery cell according to claim 2, wherein: The current blocking portion is formed of a material having a resistivity of 0.2 μΩ·m or less.

4. The battery cell according to claim 2, wherein: The current blocking portion is formed of a material having a thermal conductivity of 40 W / m·K or more.

5. The battery cell according to claim 2, wherein: The current blocking portion is made of a material having a tensile strength of 100 kgf / cm 2 The above materials are formed.

6. The battery cell according to claim 2, wherein: The current blocking portion is formed of an alloy material including tin.

7. The battery cell according to claim 6, wherein: The current blocking portion is formed of any one material selected from tin / lead, tin / lead / silver, tin / indium / silver, and tin / lead / indium.

8. The battery cell according to claim 7, wherein: The tin / lead is an alloy consisting of 60-65 weight % tin and 35-40 weight % lead, the tin / lead / silver is an alloy in which 1-2 weight % silver is added to the tin / lead, the tin / indium / silver is an alloy consisting of 75-80 weight % tin, 18-22 weight % indium and 1-5 weight % silver, and the tin / lead / indium is an alloy consisting of 68-72 weight % tin, 15-20 weight % lead and 10-15 weight % indium.

9. The battery cell according to claim 7, wherein: The current blocking portion is formed of any one material selected from Sn63 / Pb37, Sn62.5 / Pb36.1 / Ag1.4, Sn60 / Pb40, Sn77.2 / In20 / Ag2.8, and Sn70 / Pb18 / In12.

10. The battery cell according to claim 1, wherein: The electrode lead comprises: A first lead wire is disposed between the current blocking portion and the electrode tab; and The second lead is arranged on the opposite side of the first lead.

11. The battery cell according to claim 1, wherein: The electrode lead is a negative electrode lead connected to the negative electrode plate.

12. The battery cell according to claim 1, wherein: The electrode lead is formed of a copper material.

13. A battery cell comprising: an electrode assembly, formed by stacking at least one positive electrode plate and at least one negative electrode plate on each other; A shell, the electrode assembly is accommodated therein; A plurality of electrode tabs extending from the positive electrode plate and the negative electrode plate respectively; an electrode lead, one end of which is joined to the electrode tab and the other end of which extends to the outside of the shell; as well as The current blocking portion is arranged inside the electrode lead to block the flow of excess current. The current blocking part is melted in the range of 150°C-185°C, has a resistivity of less than 0.2μΩ·m, and a tensile strength of 100kgf / cm 2 The above materials are formed.

14. A battery device comprising: A plurality of battery cells, comprising a shell for accommodating an electrode assembly and an electrode lead extending from the electrode assembly and at least partially disposed outside the shell; as well as A bus bar, combined with the electrode lead, A current blocking portion for blocking the flow of an overcurrent is provided inside the electrode lead, and the current blocking portion is provided at a predetermined distance from the bus bar.

15. The battery device according to claim 14, wherein: The current blocking portion is formed of a material that melts within a temperature range of 150° C. to 185° C.

Images