KR102742761B1 - The Electrode Assembly And The Secondary Battery - Google Patents

Abstract

According to an embodiment of the present invention for solving the above problem, a pouch-type secondary battery comprises: an electrode assembly formed by stacking electrodes and a separator; and a battery case manufactured in a pouch type, accommodating the electrode assembly therein, wherein the electrode assembly comprises: a plurality of positive electrode tabs each protruding from a positive electrode among the electrodes; a plurality of negative electrode tabs each protruding from a negative electrode among the electrodes; a plurality of positive electrode leads each having one end connected to the plurality of positive electrode tabs and each extending in a direction in which the plurality of positive electrode tabs protrude; and a plurality of negative electrode leads each having one end connected to the plurality of negative electrode tabs and each extending in a direction in which the plurality of negative electrode tabs protrude.

Description

{The Electrode Assembly And The Secondary Battery}

The present invention relates to an electrode assembly and a secondary battery, and more particularly, to an electrode assembly and a secondary battery that reduce deviation in capacity and deviation in deterioration rate by making internal current and resistance uniform.

In general, types of secondary batteries include nickel cadmium batteries, nickel hydrogen batteries, lithium ion batteries, and lithium ion polymer batteries. These secondary batteries are used in not only small products such as digital cameras, P-DVDs, MP3Ps, mobile phones, PDAs, portable game devices, power tools, and e-bikes, but also large products requiring high output such as electric vehicles or hybrid vehicles, as well as power storage devices that store surplus generated power or renewable energy and backup power storage devices.

To manufacture such a secondary battery, first, an electrode active material slurry is applied to a positive electrode current collector and a negative electrode current collector to manufacture a positive electrode and a negative electrode, and these are laminated on both sides of a separator to form an electrode assembly of a predetermined shape. Then, the electrode assembly is housed in a battery case, an electrolyte is injected, and then sealed.

Secondary batteries are classified into pouch type and can type depending on the material of the case that accommodates the electrode assembly. The pouch type accommodates the electrode assembly in a pouch made of a flexible polymer material with an irregular shape.

However, in a state where the length of the pouch-type secondary battery is considerably longer than the width, electrode leads can be formed at each end in the direction of the length. Then, when electricity generated inside the secondary battery is supplied to the outside through the electrode leads, the difference in current and resistance increases between the two ends and the center of the secondary battery in the direction of the length. Therefore, a problem may arise where a deviation in the capacity (SOC, State Of Charge) occurs depending on the area of the secondary battery, and a deviation in the degradation rate also occurs.

Japanese Publication No. 2002-260712

The problem to be solved by the present invention is to provide an electrode assembly and a secondary battery that reduce deviation in capacity and deviation in deterioration rate by making internal current and resistance uniform.

The tasks of the present invention are not limited to the tasks mentioned above, and other tasks not mentioned will be clearly understood by those skilled in the art from the description below.

According to an embodiment of the present invention for solving the above problem, a pouch-type secondary battery comprises: an electrode assembly formed by stacking electrodes and a separator; and a battery case manufactured in a pouch type, accommodating the electrode assembly therein, wherein the electrode assembly comprises: a plurality of positive electrode tabs each protruding from a positive electrode among the electrodes; a plurality of negative electrode tabs each protruding from a negative electrode among the electrodes; a plurality of positive electrode leads each having one end connected to the plurality of positive electrode tabs and each extending in a direction in which the plurality of positive electrode tabs protrude; and a plurality of negative electrode leads each having one end connected to the plurality of negative electrode tabs and each extending in a direction in which the plurality of negative electrode tabs protrude.

In addition, the plurality of positive electrode tabs may be formed to protrude at least one at a first edge formed along the electric length direction of the positive electrode and at a second edge formed along the full width direction of the positive electrode, and the plurality of negative electrode tabs may be formed to protrude at least one at a third edge formed along the electric length direction of the negative electrode and at a fourth edge formed along the full width direction of the negative electrode.

Additionally, the first edge and the third edge may face each other, and the second edge and the fourth edge may also face each other.

In addition, the plurality of positive electrode tabs may be formed to protrude only at a first edge formed along the electrical length direction of the positive electrode, and the plurality of negative electrode tabs may be formed to protrude only at a third edge formed along the electrical length direction of the negative electrode.

Additionally, the plurality of positive electrode tabs and the plurality of negative electrode tabs may be formed in a row at a set interval at the first edge and the third edge, respectively.

Additionally, the first edge and the third edge may face each other.

Additionally, the plurality of positive tabs and the plurality of negative tabs can be formed at positions facing each other, respectively.

Additionally, the length to width ratio can be greater than 5:1.

According to an embodiment of the present invention for solving the above problem, an electrode assembly is provided in a pouch-type battery case, comprising: an electrode including a positive electrode and a negative electrode; a separator interposed between the electrodes and laminated together with the electrodes; a plurality of positive electrode tabs each protruding from the positive electrode among the electrodes; a plurality of negative electrode tabs each protruding from the negative electrode among the electrodes; a plurality of positive electrode leads each having one end connected to the plurality of positive electrode tabs and each extending in a direction in which the plurality of positive electrode tabs protrude; and a plurality of negative electrode leads each having one end connected to the plurality of negative electrode tabs and each extending in a direction in which the plurality of negative electrode tabs protrude.

In addition, the plurality of positive electrode tabs may be formed to protrude at least one at a first edge formed along the electric length direction of the positive electrode and at a second edge formed along the full width direction of the positive electrode, and the plurality of negative electrode tabs may be formed to protrude at least one at a third edge formed along the electric length direction of the negative electrode and at a fourth edge formed along the full width direction of the negative electrode.

In addition, the plurality of positive electrode tabs may be formed to protrude only at a first edge formed along the electrical length direction of the positive electrode, and the plurality of negative electrode tabs may be formed to protrude only at a third edge formed along the electrical length direction of the negative electrode.

According to an embodiment of the present invention for solving the above problem, a secondary battery includes a plurality of positive electrodes, positive electrode tabs, negative electrodes, negative electrode tabs; and a separator disposed between the positive electrodes and the negative electrodes, wherein the plurality of positive electrode tabs and the plurality of negative electrode tabs are disposed along the longitudinal direction of each of the positive electrodes and the negative electrodes, the positive electrode tabs and the negative electrode tabs on the positive electrodes and the negative electrodes are formed on different surfaces, and further includes a plurality of positive electrode leads each having one end connected to the plurality of positive electrode tabs and each extending in a direction in which the plurality of positive electrode tabs protrude; and a plurality of negative electrode leads each having one end connected to the plurality of negative electrode tabs and each extending in a direction in which the plurality of negative electrode tabs protrude.

Additionally, the plurality of positive tabs and the plurality of negative tabs may have a trapezoidal shape.

The present invention also provides a battery module including the pouch-type secondary battery.

The above pouch-type secondary battery is formed in multiples, and the multiple positive electrode leads corresponding to each other can be connected to each other, and the multiple negative electrode leads corresponding to each other can be connected to each other.

The present invention also provides a battery pack including the battery module.

The present invention also provides a device including the battery pack.

The above devices may include, but are not limited to, a computer, a laptop, a smartphone, a mobile phone, a tablet PC, a wearable electronic device, a power tool, an electric vehicle (EV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), or a power storage device.

Other specific details of the present invention are included in the detailed description and drawings.

According to embodiments of the present invention, at least the following effects are achieved.

Since the positive and negative tabs of the electrode assembly are formed in multiple numbers and protrude in various directions at various locations, the current and resistance inside the electrode assembly become uniform, so that the deviation in capacity and the deviation in deterioration rate can be reduced.

The effects according to the present invention are not limited to those exemplified above, and further diverse effects are included in the present specification.

Figure 1 is an assembly diagram of a secondary battery according to one embodiment of the present invention.
Figure 2 is a schematic diagram of an anode according to one embodiment of the present invention.
Figure 3 is a schematic diagram of a cathode according to one embodiment of the present invention.
Figure 4 is a perspective view of a secondary battery according to one embodiment of the present invention.
Figure 5 is an assembly diagram of a secondary battery according to another embodiment of the present invention.
Figure 6 is a schematic diagram of an anode according to another embodiment of the present invention.
Figure 7 is a schematic diagram of a cathode according to another embodiment of the present invention.
Figure 8 is a perspective view of a secondary battery according to another embodiment of the present invention.

The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms, and the present embodiments are provided only to make the disclosure of the present invention complete and to fully inform those skilled in the art of the scope of the invention, and the present invention is defined only by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with a meaning that can be commonly understood by a person of ordinary skill in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries shall not be ideally or excessively interpreted unless explicitly specifically defined.

The terminology used herein is for the purpose of describing embodiments only and is not intended to limit the invention. In this specification, the singular also includes the plural unless specifically stated otherwise. The terms "comprises" and/or "comprising" as used herein do not exclude the presence or addition of one or more other components in addition to the components mentioned.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

Figure 1 is an assembly diagram of a secondary battery (1) according to one embodiment of the present invention.

According to one embodiment of the present invention, since the positive electrode tab (111) and the negative electrode tab (112) of the electrode assembly (10) are formed in multiple numbers and protrude in various directions at various positions, the current and resistance inside the electrode assembly (10) become uniform, so that the deviation in capacity and the deviation in deterioration rate can be reduced.

To this end, an electrode assembly (10) according to one embodiment of the present invention is an electrode assembly (10) accommodated in a pouch-type battery case (13), including an electrode including a positive electrode (101, illustrated in FIG. 2) and a negative electrode (102, illustrated in FIG. 3); a separator interposed between the electrodes and laminated together with the electrodes; a plurality of positive electrode tabs (111) each protruding from the positive electrode (101) among the electrodes; a plurality of negative electrode tabs (112) each protruding from the negative electrode (102) among the electrodes; a plurality of positive electrode leads (121) each having one end connected to the plurality of positive electrode tabs (111) and each extending in a direction in which the plurality of positive electrode tabs (111) protrude; and a plurality of negative electrode leads (122) each having one end connected to the plurality of negative electrode tabs (112) and each extending in a direction in which the plurality of negative electrode tabs (112) protrude. And, the plurality of positive electrode tabs (111) may be formed to protrude at least one at a first edge (1011, illustrated in FIG. 2) formed along the longitudinal direction of the positive electrode (101) and a second edge (1012, illustrated in FIG. 2) formed along the width direction of the positive electrode (101), and the plurality of negative electrode tabs (112) may be formed to protrude at least one at a third edge (1023, illustrated in FIG. 3) formed along the longitudinal direction of the negative electrode (102) and a fourth edge (1024, illustrated in FIG. 3) formed along the width direction of the negative electrode (102).

And, a pouch-type secondary battery (1) according to one embodiment of the present invention includes an electrode assembly (10) formed by stacking electrodes and a separator; and a battery case (13) manufactured in a pouch type, which accommodates the electrode assembly (10) therein, wherein the electrode assembly (10) includes: a plurality of positive electrode tabs (111) each protruding from a positive electrode (101) among the electrodes; a plurality of negative electrode tabs (112) each protruding from a negative electrode (102) among the electrodes; a plurality of positive electrode leads (121) each having one end connected to the plurality of positive electrode tabs (111) and each extending in a direction in which the plurality of positive electrode tabs (111) protrude; and a plurality of negative electrode leads (122) each having one end connected to the plurality of negative electrode tabs (112) and each extending in a direction in which the plurality of negative electrode tabs (112) protrude. And the plurality of positive electrode tabs (111) may be formed to protrude at least one each at a first edge (1011) formed along the longitudinal direction of the positive electrode (101) and a second edge (1012) formed along the width direction of the positive electrode (101), and the plurality of negative electrode tabs (112) may be formed to protrude at least one each at a third edge (1023) formed along the longitudinal direction of the negative electrode (102) and a fourth edge (1024) formed along the width direction of the negative electrode (102).

In addition, according to one embodiment of the present invention, a secondary battery includes a plurality of positive electrodes, positive electrode tabs, negative electrodes, negative electrode tabs; and a separator disposed between the positive electrodes and the negative electrodes, wherein the plurality of positive electrode tabs and the plurality of negative electrode tabs are disposed along the longitudinal direction of each of the positive electrodes and the negative electrodes, and the positive electrode tabs and the negative electrode tabs on the positive electrodes and the negative electrodes are formed on different surfaces, and the plurality of positive electrode leads each having one end connected to the plurality of positive electrode tabs and each extending in a direction in which the plurality of positive electrode tabs protrude; and the plurality of negative electrode leads each having one end connected to the plurality of negative electrode tabs and each extending in a direction in which the plurality of negative electrode tabs protrude.

The process for manufacturing such a pouch-type secondary battery (1) is as follows: first, a slurry containing an electrode active material, a binder, and a plasticizer is applied to a positive electrode current collector and a negative electrode current collector to manufacture a positive electrode (101) and a negative electrode (102), and these are laminated on both sides of a separator to form an electrode assembly (10) of a predetermined shape. Then, the electrode assembly (10) is inserted into a battery case (13), an electrolyte is injected, and then sealed.

Specifically, the electrode assembly (Electrode Assembly, 10) includes two types of electrodes, such as a positive electrode (101) and a negative electrode (102), and a separator interposed between the electrodes to mutually insulate the electrodes. The electrode assembly (10) may be of a stack type, a jelly roll type, a stack-and-fold type, etc., but according to one embodiment of the present invention, since a plurality of electrode tabs (11) are formed to protrude in various directions from one positive electrode (101) and negative electrode (102), it is preferable that the electrode assembly (10) be of a stack type in which a plurality of positive electrodes (101) and negative electrodes (102) are simply and repeatedly stacked with a separator interposed therebetween. The two types of electrodes, that is, the positive electrode (101) and negative electrode (102), each have a structure in which an active material slurry is applied to an electrode current collector in the form of a metal foil or metal mesh containing aluminum and copper. The slurry can typically be formed by stirring a granular active material, an auxiliary conductor, a binder, a plasticizer, etc. in a state in which a solvent is added. The solvent is removed in a subsequent process.

The electrode assembly (10) includes an electrode tab (11), as illustrated in FIG. 1. The electrode tab (11) protrudes from each of the positive electrode (101) and the negative electrode (102) of the electrode assembly (10), thereby forming a path through which electrons can move between the inside and the outside of the electrode assembly (10). The current collector of the electrode assembly (10) is composed of a portion where an electrode active material is applied and a terminal portion where the electrode active material is not applied, i.e., a non-coated portion. In addition, the electrode tab (11) may be formed by cutting the non-coated portion or by connecting a separate conductive member to the non-coated portion by ultrasonic welding, etc.

According to one embodiment of the present invention, the electrode tab (11) includes a plurality of positive electrode tabs (111) each protruding from the positive electrode (101) and a plurality of negative electrode tabs (112) each protruding from the negative electrode (102). Specifically, as illustrated in FIG. 1, a plurality of positive electrode tabs (111) are formed to protrude in various directions from one positive electrode (101), and a plurality of negative electrode tabs (112) are formed to protrude in various directions from one negative electrode (102). In addition, the positions and protruding directions in which the plurality of positive electrode tabs (111) and the plurality of negative electrode tabs (112) are formed are different from each other. The plurality of positive electrode tabs (111) and the plurality of negative electrode tabs (112) may be formed in a rectangular shape, but may also be formed in a trapezoidal shape, and are not limited thereto, and may be formed in various shapes.

Meanwhile, a plurality of positive electrodes (101) and a plurality of negative electrodes (102) are laminated to manufacture an electrode assembly (10). At this time, for each of the plurality of positive electrodes (101) to be laminated, a plurality of positive electrode tabs (111) may all be formed to protrude in the same direction at the same position, and a plurality of negative electrode tabs (112) may all be formed to protrude in the same direction at the same position for each of the plurality of negative electrodes (102). Accordingly, by being formed to protrude in the same direction at the same position, the positive electrode tabs (111) and negative electrode tabs (112) that correspond to each other are connected (welded, bonded), and a positive electrode lead (121) and a negative electrode lead (122) may also be connected to each of the positive electrode tabs (111) and negative electrode tabs (112).

An electrode lead (12) is connected to an electrode tab (11) of an electrode assembly (10) by spot welding or the like. In addition, a portion of the electrode lead (12) is surrounded by an insulating portion (14). The insulating portion (14) is positioned limited to a sealing portion where the upper case (131) and the lower case (132) of the battery case (13) are heat-welded, and is adhered to the battery case (13). In addition, it prevents electricity generated from the electrode assembly (10) from flowing to the battery case (13) through the electrode lead (12), and maintains the sealing of the battery case (13). Therefore, this insulating portion (14) is made of a non-conductive material that does not conduct electricity well. In general, as the insulating part (14), an insulating tape that is easy to attach to the electrode lead (12) and has a relatively thin thickness is often used, but it is not limited thereto and various materials can be used as long as they can insulate the electrode lead (12).

The electrode lead (12) includes a plurality of positive leads (121) each having one end connected to a plurality of positive tabs (111) and extending in a direction in which the plurality of positive tabs (111) protrude, and a plurality of negative leads (122) each having one end connected to a plurality of negative tabs (112) and extending in a direction in which the plurality of negative tabs (112) protrude. When corresponding electrode tabs (11) are connected to each other, the connected electrode tabs (11) form a group, and the electrode leads (12) are connected one by one to each group of electrode tabs (11). Therefore, it is preferable that the number of electrode leads (12) is the same as the number of groups formed by the electrode tabs (11). In particular, the number of positive leads (121) is the same as the number of groups formed by the positive tabs (111), and the number of negative leads (122) is the same as the number of groups formed by the negative tabs (112).

Meanwhile, as shown in Fig. 1, both the positive lead (121) and the negative lead (122) protrude to the outside of the battery case (13) at the other end. As a result, electricity generated inside the electrode assembly (10) can be supplied to the outside. In addition, since the positive tab (111) and the negative tab (112) are formed to protrude in various directions, the positive lead (121) and the negative lead (122) can also extend in various directions, respectively.

The positive electrode lead (121) and the negative electrode lead (122) may be made of different materials. That is, the positive electrode lead (121) may be made of the same aluminum (Al) material as the positive electrode (101) plate, and the negative electrode lead (122) may be made of the same copper (Cu) material as the negative electrode (102) plate or a copper material coated with nickel (Ni). In addition, the other end of the electrode lead (12) protruding outside the battery case (13) becomes a terminal portion and is electrically connected to an external terminal.

The battery case (13) is a pouch made of a flexible material. The battery case (13) accommodates and seals the electrode assembly (10) so that a part of the electrode lead (12), i.e., the terminal part, is exposed. The battery case (13), as illustrated in FIG. 1, includes an upper case (131) and a lower case (132). A cup portion (133) is formed in the lower case (132) to provide an accommodation space (1331) capable of accommodating the electrode assembly (10), and the upper case (131) covers the accommodation space (1331) from the top so that the electrode assembly (10) does not fall out of the battery case (13). In FIG. 1, the cup portion (133) is illustrated as being formed only in the lower case (132), but it is not limited thereto and may be formed in various ways, such as being formed in the upper case (131).

The upper case (131) and the lower case (132) may be manufactured separately and separated from each other as illustrated in FIG. 1, but are not limited thereto and may be manufactured as an integral body with one side connected to each other. In addition, the battery case (13) may have a length ratio of the total length and the total width of approximately 5:1 or more. Accordingly, the secondary battery (1) also has a length ratio of the total length and the total width of approximately 5:1 or more. However, if the electrode leads (12) are formed only at both ends in the length direction while the total length of the secondary battery (1) is considerably longer than the total width, a problem may arise whereby a deviation in the capacity (SOC, State Of Charge) occurs depending on the area of the secondary battery (1), and thus a deviation in the degradation rate may also occur. However, according to one embodiment of the present invention, since the positive tab (111) and the negative tab (112) of the electrode assembly (10) are formed in multiple numbers and protrude in various directions at various positions, the current and resistance inside the electrode assembly (10) become uniform, so that the deviation in capacity and the deviation in deterioration rate can be reduced.

When the electrode lead (12) is connected to the electrode tab (11) of the electrode assembly (10) and the insulating portion (14) is formed on a portion of the electrode lead (12), the electrode assembly (10) is accommodated in the accommodation space (1331) provided in the cup portion (133) of the lower case (132), and the upper case (131) covers the space from above. Then, an electrolyte is injected inside, and a sealing portion formed on the edges of the upper case (131) and the lower case (132) is sealed. The electrolyte is for moving lithium ions generated by an electrochemical reaction of an electrode during charging and discharging of the secondary battery (1), and may include a non-aqueous organic electrolyte that is a mixture of a lithium salt and a high-purity organic solvent, or a polymer using a polymer electrolyte. Through this method, a pouch-type secondary battery (1) can be manufactured.

Figure 2 is a schematic diagram of an anode (101) according to one embodiment of the present invention.

According to one embodiment of the present invention, one anode (101) has a plurality of anode tabs (111), as illustrated in FIG. 2. At this time, at least one anode tab (111) is formed to protrude at each of a first edge (1011) formed along the longitudinal direction of the anode (101) and a second edge (1012) formed along the longitudinal direction of the anode (101). In FIG. 2, only one first anode tab (1111) is formed at the first edge (1011) and only one second anode tab (1112) is formed at the second edge (1012). However, the present invention is not limited thereto, and a plurality of anode tabs (111) may be formed at at least one of the first edge (1011) and the second edge (1012), or the like. However, as described below, a plurality of anode tabs (112) may also be formed to protrude at one anode (102). At this time, it is preferable that the corners where the positive tab (111) is formed and the corners where the negative tab (112) is formed face each other. To this end, the positive tab (111) may not be formed at the third corner (1013) and the fourth corner (1014) of the positive electrode (101).

In Fig. 2, only one anode (101) is illustrated, but a plurality of anodes (101) may be used to manufacture the electrode assembly (10). At this time, all of the plurality of anodes (101) have a plurality of anode tabs (111), and the plurality of anode tabs (111) of each of the plurality of anodes (101) are formed to protrude in the same direction at the same position. Accordingly, when the electrode assembly (10) is manufactured, the anode tabs (111) that are formed to protrude in the same direction at the same position of the electrode assembly (10) and correspond to each other can be connected. When the corresponding anode tabs (111) are connected to each other, the anode tabs (111) that are connected to each other form a group, and the anode leads (121) are connected one by one to each group of the anode tabs (111). For example, as illustrated in FIG. 2, if a first positive electrode tab (1111) is formed to protrude from a first edge (1011) and a second positive electrode tab (1112) is formed to protrude from a second edge (1012) of each of a plurality of positive electrodes (101), a plurality of first positive electrode tabs (1111) are formed to protrude from the first edge (1011) of the electrode assembly (10), and a plurality of second positive electrode tabs (1112) are formed to protrude from the second edge (1012). Then, the first positive electrode tabs (1111) that correspond to each other are connected to form one group, and the second positive electrode tabs (1112) that correspond to each other are connected to form another group.

Figure 3 is a schematic diagram of a cathode (102) according to one embodiment of the present invention.

According to one embodiment of the present invention, a single cathode (102) has a plurality of cathode tabs (112), as illustrated in FIG. 3. At this time, at least one cathode tab (112) is protrudingly formed at each of a third edge (1023) formed along the longitudinal direction of the cathode (102) and a fourth edge (1024) formed along the width direction of the cathode (102). In FIG. 3, only one first cathode tab (1121) is formed at the third edge (1023) and only one second cathode tab (1122) is formed at the fourth edge (1024), but the present invention is not limited thereto and may be formed in various ways, such as a plurality of cathode tabs (112) being formed at at least one of the third edge (1023) and the fourth edge (1024).

In Fig. 3, only one cathode (102) is illustrated, but a plurality of cathodes (102) may be used to manufacture the electrode assembly (10). In this case, all of the plurality of cathodes (102) have a plurality of cathode tabs (112), and the plurality of cathode tabs (112) of each of the plurality of cathodes (102) are formed to protrude in the same direction at the same position. Accordingly, when the electrode assembly (10) is manufactured, the cathode tabs (112) that are formed to protrude in the same direction at the same position of the electrode assembly (10) and correspond to each other can be connected. When the corresponding cathode tabs (112) are connected to each other, the connected cathode tabs (112) form a group, and the cathode leads (122) are connected one by one to each group of cathode tabs (112). For example, as illustrated in FIG. 3, if a first negative electrode tab (1121) is formed to protrude from a third edge (1023) and a second negative electrode tab (1122) is formed to protrude from a fourth edge (1024) of each of a plurality of negative electrodes (102), a plurality of first negative electrode tabs (1121) are formed to protrude from the third edge (1023) of the electrode assembly (10), and a plurality of second negative electrode tabs (1122) are formed to protrude from the fourth edge (1024). Then, the first negative electrode tabs (1121) that correspond to each other are connected to form one group, and the second negative electrode tabs (1122) that correspond to each other are connected to form another group.

As described above, a plurality of positive electrodes (101) and a plurality of negative electrodes (102) are used to manufacture the electrode assembly (10). At this time, it is preferable that the positive electrode tabs (111) and the negative electrode tabs (112) are formed to protrude at different corners. That is, the positive electrode tabs (111) may not be formed at the third corner (1013) and the fourth corner (1014) of the positive electrode (101), and the negative electrode tabs (112) may not be formed at the first corner (1021) and the second corner (1022) of the negative electrode (102). In addition, it is preferable that the corners where the positive electrode tabs (111) are formed and the corners where the negative electrode tabs (112) are formed face each other. That is, the first corners (1011, 1021) and the third corners (1013, 1023) formed along the electric field direction face each other. And, the second corner (1012, 1022) and the fourth corner (1014, 1024) formed along the full width direction face each other.

In addition, a plurality of positive electrode tabs (111) and a plurality of negative electrode tabs (112) are formed at positions facing each other, respectively. For example, since the first positive electrode tab (1111) and the first negative electrode tab (1121) are formed at positions facing each other, when electricity is generated inside the electrode assembly (10), current can flow between the first positive electrode tab (1111) and the first negative electrode tab (1121) facing each other in the full width direction of the electrode assembly (10). In particular, as described above, since the length ratio of the total length and the full width of the secondary battery (1) is approximately 5:1 or more, a capacity decrease may occur at approximately the center of the electrode assembly (1), resulting in a capacity deviation. Therefore, it is preferable that the first positive electrode tab (1111) and the first negative electrode tab (1121) are formed at positions facing each other, approximately at the center of the first edge (1011) and the third edge (1023) formed along the electric field direction, respectively. As a result, the current and resistance inside the electrode assembly (10) become uniform, so that the deviation in capacity and the deviation in deterioration rate can be reduced.

Figure 4 is a perspective view of a secondary battery (1) according to one embodiment of the present invention.

When a secondary battery (1) according to one embodiment of the present invention is manufactured, the other end of the electrode lead (12) protrudes to the outside of the battery case (13). For example, as illustrated in FIG. 4, when the first positive electrode tabs (1111) protruding from the first edge (1011) of the electrode assembly (10) are connected, one end of the first positive electrode lead (1211) is connected to a single group formed by connecting the first positive electrode tabs (1111), and the first positive electrode lead (1211) extends toward the direction in which the first positive electrode tabs (1111) protrude. Then, the other end of the first positive electrode lead (1211) protrudes to the outside of the battery case (13). In addition, when the second positive electrode tabs (1112) protruding from the second edge (1012) of the electrode assembly (10) are connected, one end of the second positive electrode lead (1212) is connected to another group formed by connecting the second positive electrode tabs (1112), and the second positive electrode lead (1212) extends toward the direction in which the second positive electrode tabs (1112) protrude. Then, the other end of the second positive electrode lead (1212) protrudes to the outside of the battery case (13).

At this time, since the positive lead (121) is extended in the direction in which the positive tab (111) protrudes, the other end of the first positive lead (1211) protrudes from the edge of the battery case (13) corresponding to the first edge (1011) of the electrode assembly (10), and the other end of the second positive lead (1212) protrudes from the edge of the battery case (13) corresponding to the second edge (1012) of the electrode assembly (10).

When the first negative tabs (1121) protruding from the third edge (1023) of the electrode assembly (10) are connected, one end of the first negative lead (1221) is connected to one group formed by connecting the first negative tabs (1121), and the first negative lead (1221) extends toward the direction in which the first negative tabs (1121) protrude. Then, the other end of the first negative lead (1221) protrudes to the outside of the battery case (13). In addition, when the second negative tabs (1122) protruding from the fourth edge (1024) of the electrode assembly (10) are connected, one end of the second negative lead (1222) is connected to another group formed by connecting the second negative tabs (1122) and the second negative lead (1222) extends toward the direction in which the second negative tabs (1122) protrude. And the other end of the second negative lead (1222) protrudes outside the battery case (13).

At this time, since the negative lead (122) is extended in the direction in which the negative tab (112) protrudes, the other end of the first negative lead (1221) protrudes from the corner of the battery case (13) corresponding to the third corner (1023) of the electrode assembly (10), and the other end of the second negative lead (1222) protrudes from the corner of the battery case (13) corresponding to the fourth corner (1024) of the electrode assembly (10).

Meanwhile, a battery module including a pouch-type secondary battery (1) according to one embodiment of the present invention may be manufactured. At this time, the pouch-type secondary battery (1) is formed in multiples, and a plurality of positive electrode leads (121) corresponding to each other may be connected to each other, and a plurality of negative electrode leads (122) corresponding to each other may be connected to each other.

Figure 5 is an assembly diagram of a secondary battery (1a) according to another embodiment of the present invention.

According to one embodiment of the present invention, at least one electrode lead (12) is formed at each of the two ends in the longitudinal direction of the secondary battery (1). However, according to another embodiment of the present invention, as shown in FIG. 5, the electrode leads (12a) are not formed at each end in the longitudinal direction of the secondary battery (1a), but are formed only at each end in the longitudinal direction.

Hereinafter, the contents of other embodiments of the present invention will be described, but the description of any overlapping contents with the contents of one embodiment of the present invention described above will be omitted. This is for the convenience of explanation and is not intended to limit the scope of rights.

Figure 6 is a schematic diagram of an anode (101a) according to another embodiment of the present invention.

According to another embodiment of the present invention, one anode (101a) has a plurality of anode tabs (111a), as illustrated in FIG. 6. At this time, the plurality of anode tabs (111a) are each formed to protrude only at the first edge (1011) formed along the electric field direction of the anode (101a). That is, the anode tabs (111a) are not formed at the second edge (1012), the third edge (1013), and the fourth edge (1014) of the anode (101a). In addition, these plurality of anode tabs (111a) are formed in a row at regular intervals at each of the first edges (1011). In Fig. 6, a first positive electrode tab (1111a), a second positive electrode tab (1112a), and a third positive electrode tab (1113a), a total of three positive electrode tabs (111a) are formed at regular intervals on the first edge (1011), but this is not limited thereto and various numbers, such as two or four or more, may be formed. However, as described below, a plurality of negative electrode tabs (112a) may be formed protrudingly on one negative electrode (102a). At this time, it is preferable that the edges on which the positive electrode tabs (111a) are formed and the edges on which the negative electrode tabs (112a) are formed face each other.

When the electrode assembly (10a) is manufactured and the corresponding positive electrode tabs (111a) are connected to each other, the positive electrode tabs (111a) that are connected to each other form a group, and the positive electrode leads (121a) are connected one by one to each group of positive electrode tabs (111a). For example, as illustrated in FIG. 6, if a first positive electrode tab (1111a), a second positive electrode tab (1112a), and a third positive electrode tab (1113a) are formed at regular intervals at the first edge (1011) of each of a plurality of positive electrodes (101a), the first positive electrode tab (1111a), a second positive electrode tab (1112a), and a third positive electrode tab (1113a) are also formed at regular intervals at the first edge (1011) of the electrode assembly (10a). And, the first positive electrode tabs (1111a) that correspond to each other are connected to form one group, the second positive electrode tabs (1112a) that correspond to each other are connected to form another group, and the third positive electrode tabs (1113a) that correspond to each other are connected to form yet another group.

Figure 7 is a schematic diagram of a cathode (102a) according to another embodiment of the present invention.

According to another embodiment of the present invention, one cathode (102a) has a plurality of cathode tabs (112a), as illustrated in FIG. 7. At this time, the plurality of cathode tabs (112a) are each formed to protrude only at the third edge (1023) formed along the electric field direction of the cathode (102a). That is, the cathode tabs (112a) are not formed at the first edge (1021), the second edge (1022), and the fourth edge (1024) of the cathode (102a). In addition, these plurality of cathode tabs (112a) are formed in a row at regular intervals at the third edge (1023), respectively. In FIG. 7, a first negative tab (1121a), a second negative tab (1122a), and a third negative tab (1123a), a total of three negative tabs (112a) are formed at regular intervals at the third corner (1023), but this is not limited thereto and various numbers, such as two or four or more, may be formed.

When the electrode assembly (10a) is manufactured and the corresponding negative tabs (112a) are connected to each other, the connected negative tabs (112a) form a group, and the negative lead (122a) is connected to each group of negative tabs (112a). For example, as illustrated in FIG. 7, if a first negative tab (1121a), a second negative tab (1122a), and a third negative tab (1123a) are formed at regular intervals at the third edge (1023) of each of a plurality of negative electrodes (102a), the first negative tab (1121a), the second negative tab (1122a), and the third negative tab (1123a) are also formed at regular intervals at the third edge (1023) of the electrode assembly (10a). And, the first negative tabs (1121a) that correspond to each other are connected to form one group, the second negative tabs (1122a) that correspond to each other are connected to form another group, and the third negative tabs (1123a) that correspond to each other are connected to form yet another group.

It is preferable that the positive tab (111a) and the negative tab (112a) are formed to protrude from different edges, and it is preferable that the edges where the positive tab (111a) is formed and the edges where the negative tab (112a) is formed face each other. That is, the first edge (1011, 1021) formed along the electric field direction and the third edge (1013, 1023) formed along the electric field direction face each other.

In addition, the plurality of positive electrode tabs (111a) and the plurality of negative electrode tabs (112a) are formed at positions facing each other, respectively. For example, since the first positive electrode tab (1111a) and the first negative electrode tab (1121a) are formed at positions facing each other, when electricity is generated inside the electrode assembly (10a), current can flow between the first positive electrode tab (1111a) and the first negative electrode tab (1121a) facing each other in the full width direction of the electrode assembly (10a). In particular, a capacity decrease may occur at the approximate center of the electrode assembly (1), resulting in a capacity deviation. Therefore, it is preferable that at least one of the plurality of positive electrode tabs (111a) and the plurality of negative electrode tabs (112a) is formed at a position facing each other at the approximate center of the first edge (1011) and the third edge (1023) formed along the electric field direction, respectively. By doing so, the current and resistance inside the electrode assembly (10) become uniform, so that the deviation in capacity and the deviation in deterioration rate can be reduced.

Furthermore, when a plurality of positive electrode tabs (111a) and a plurality of negative electrode tabs (112a) are formed in a row at regular intervals, it is preferable that they are formed in a uniform row at the first edge (1011) and the third edge (1023), respectively.

Figure 8 is a perspective view of a secondary battery (1a) according to another embodiment of the present invention.

When a secondary battery (1a) according to another embodiment of the present invention is manufactured, the other end of the electrode lead (12a) protrudes outside the battery case (13). For example, as illustrated in FIG. 8, when the first positive electrode tabs (1111a) of the electrode assembly (10a) are connected to each other, one end of the first positive electrode lead (1211a) is connected to one group formed by connecting the first positive electrode tabs (1111a), and the first positive electrode lead (1211a) extends toward the direction in which the first positive electrode tabs (1111a) protrude. Then, the other end of the first positive electrode lead (1211a) protrudes outside the battery case (13). In addition, when the second positive tabs (1112a) of the electrode assemblies (10a) are connected, one end of the second positive lead (1212a) is connected to another group formed by connecting the second positive tabs (1112a), and the second positive lead (1212a) extends toward the protruding direction of the second positive tabs (1112a). And the other end of the second positive lead (1212a) protrudes to the outside of the battery case (13). In addition, when the third positive tabs (1113a) of the electrode assemblies (10a) are connected, one end of the third positive lead (1213a) is connected to another group formed by connecting the third positive tabs (1113a), and the third positive lead (1213a) extends toward the protruding direction of the third positive tabs (1113a). And the other end of the third positive lead (1213a) protrudes to the outside of the battery case (13).

At this time, since the positive lead (121a) is extended in the direction in which the positive tab (111a) protrudes, the other ends of the first to third positive leads (1213a) all protrude from the corner of the battery case (13) corresponding to the first corner (1011) of the electrode assembly (10a), and are respectively formed in a row at a set interval.

When the first positive electrode tabs (1111a) of the electrode assemblies (10a) are connected to each other, one end of the first positive electrode lead (1211a) is connected to one group formed by connecting the first positive electrode tabs (1111a), and the first positive electrode lead (1211a) extends in the direction in which the first positive electrode tabs (1111a) protrude. Then, the other end of the first positive electrode lead (1211a) protrudes to the outside of the battery case (13). In addition, when the second positive electrode tabs (1112a) of the electrode assemblies (10a) are connected to each other, one end of the second positive electrode lead (1212a) is connected to another group formed by connecting the second positive electrode tabs (1112a), and the second positive electrode lead (1212a) extends in the direction in which the second positive electrode tabs (1112a) protrude. Then, the other end of the second positive electrode lead (1212a) protrudes to the outside of the battery case (13). In addition, when the third positive electrode tabs (1113a) of the electrode assembly (10a) are connected to each other, one end of the third positive electrode lead (1213a) is connected to another group formed by connecting the third positive electrode tabs (1113a), and the third positive electrode lead (1213a) extends toward the direction in which the third positive electrode tab (1113a) protrudes. And the other end of the third positive electrode lead (1213a) protrudes to the outside of the battery case (13).

When the first negative tabs (1121a) of the electrode assemblies (10a) are connected to each other, one end of the first negative lead (1221a) is connected to one group formed by connecting the first negative tabs (1121a), and the first negative lead (1221a) extends toward the direction in which the first negative tabs (1121a) protrude. Then, the other end of the first negative lead (1221a) protrudes to the outside of the battery case (13). In addition, when the second negative tabs (1122a) of the electrode assemblies (10a) are connected to each other, one end of the second negative lead (1222a) is connected to another group formed by connecting the second negative tabs (1122a), and the second negative lead (1222a) extends toward the direction in which the second negative tabs (1122a) protrude. And the other end of the second negative electrode lead (1222a) protrudes outside the battery case (13). In addition, when the third negative electrode tabs (1123a) of the electrode assembly (10a) are connected to each other, one end of the third negative electrode lead (1223a) is connected to another group formed by connecting the third negative electrode tabs (1123a), and the third negative electrode lead (1223a) extends toward the direction in which the third negative electrode tab (1123a) protrudes. And the other end of the third negative electrode lead (1223a) protrudes outside the battery case (13).

At this time, since the negative lead (122a) is extended in the direction in which the negative tab (112a) protrudes, the other ends of the first to third negative leads (1223a) all protrude from the corner of the battery case (13) corresponding to the third corner (1023) of the electrode assembly (10a), and are respectively formed in a row at a certain interval.

Those skilled in the art will appreciate that the present invention can be implemented in other specific forms without changing the technical idea or essential characteristics thereof. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is indicated by the claims described below rather than the detailed description above, and various embodiments derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

1: Secondary battery 10: Electrode assembly
11: Electrode tab 12: Electrode lead
13: Battery case 14: Insulator
101: Anode 102: Cathode
111: Positive tab 112: Negative tab
121: Positive lead 122: Negative lead
131: Upper case 132: Lower case
133: Cup part 134: Sealing part
1331: Reception space 1011, 1021: 1st corner
1012, 1022: 2nd corner 1013, 1023: 3rd corner
1014, 1024: 4th corner 1111: 1st positive tab
1112: Second anode tab 1113a: Third anode tab
1121: First cathode tab 1122: Second cathode tab
1123a: Third negative tab 1211: First positive lead
1212: Second positive lead 1213a: Third positive lead
1221: First negative lead 1222: Second negative lead
1223a: Third cathode lead

Claims (18)

An electrode assembly formed by stacking electrodes and a separator; and
A battery case manufactured in a pouch shape, which houses the electrode assembly inside,
The above electrode assembly is,
A plurality of anode tabs each protruding from the anode among the above electrodes;
A plurality of cathode tabs each protruding from the cathode among the above electrodes;
A plurality of anode leads, each of which has one end connected to each of the plurality of anode tabs and each extending in a direction in which the plurality of anode tabs protrude; and
A plurality of negative leads each having one end connected to each of the plurality of negative tabs and each extending in a direction in which the plurality of negative tabs protrude,
The above multiple positive electrode tabs are,
At least one protrusion is formed at each of the first edge formed along the electric field direction of the anode and the second edge formed along the full width direction of the anode,
The above multiple negative tabs are,
At least one protrusion is formed at each of the third edge formed along the electric field direction of the cathode and the fourth edge formed along the full width direction of the cathode,
The above first corner and the above third corner,
Opposite each other,
The second corner and the fourth corner above,
Pouch-type secondary batteries facing each other. delete delete An electrode assembly formed by stacking electrodes and a separator; and
A battery case manufactured in a pouch shape, which houses the electrode assembly inside,
The above electrode assembly is,
A plurality of anode tabs each protruding from the anode among the above electrodes;
A plurality of cathode tabs each protruding from the cathode among the above electrodes;
A plurality of anode leads, each of which has one end connected to each of the plurality of anode tabs and each extending in a direction in which the plurality of anode tabs protrude; and
A plurality of negative leads each having one end connected to each of the plurality of negative tabs and each extending in a direction in which the plurality of negative tabs protrude,
The above multiple positive electrode tabs are,
Each protrusion is formed only at the first edge formed along the electric field direction of the above anode,
The above multiple negative tabs are,
Each protrusion is formed only at the third corner formed along the electrical field direction of the above cathode,
The above first corner and the above third corner,
Pouch-type secondary batteries facing each other. In paragraph 4,
The above plurality of positive tabs and the above plurality of negative tabs,
A pouch-type secondary battery, each of which is formed at a set interval along the first and third corners. delete In paragraph 1 or 4,
The above plurality of positive tabs and the above plurality of negative tabs,
A pouch-type secondary battery, each formed in a position facing each other. In paragraph 1 or 4,
A pouch-type secondary battery having a length-to-width ratio of 5:1 or more. In an electrode assembly accommodated in a pouch-type battery case,
An electrode comprising an anode and a cathode;
A separator interposed between the electrodes and laminated together with the electrodes;
A plurality of anode tabs each protruding from the anode among the above electrodes;
A plurality of cathode tabs each protruding from the cathode among the above electrodes;
A plurality of anode leads, each of which has one end connected to each of the plurality of anode tabs and each extending in a direction in which the plurality of anode tabs protrude; and
A plurality of negative leads each having one end connected to each of the plurality of negative tabs and each extending in a direction in which the plurality of negative tabs protrude,
The above multiple positive electrode tabs are,
At least one protrusion is formed at each of the first edge formed along the electric field direction of the anode and the second edge formed along the full width direction of the anode,
The above multiple negative tabs are,
At least one protrusion is formed at each of the third edge formed along the electric field direction of the cathode and the fourth edge formed along the full width direction of the cathode,
The above first corner and the above third corner,
Opposite each other,
The second corner and the fourth corner above,
Opposing electrode assemblies. delete In an electrode assembly accommodated in a pouch-type battery case,
An electrode comprising an anode and a cathode;
A separator interposed between the electrodes and laminated together with the electrodes;
A plurality of anode tabs each protruding from the anode among the above electrodes;
A plurality of cathode tabs each protruding from the cathode among the above electrodes;
A plurality of anode leads, each of which has one end connected to each of the plurality of anode tabs and each extending in a direction in which the plurality of anode tabs protrude; and
A plurality of negative leads each having one end connected to each of the plurality of negative tabs and each extending in a direction in which the plurality of negative tabs protrude,
The above multiple positive electrode tabs are,
Each protrusion is formed only at the first edge formed along the electric field direction of the above anode,
The above multiple negative tabs are,
Each protrusion is formed only at the third corner formed along the electrical field direction of the above cathode,
The above first corner and the above third corner,
Opposing electrode assemblies. delete delete A battery module comprising a pouch-type secondary battery according to claim 1 or 4. In Article 14,
The above pouch-type secondary battery,
It is formed by revenge,
A plurality of the above positive leads are connected to each other,
A battery module in which a plurality of corresponding negative leads are connected to each other. A battery pack comprising a battery module according to Article 14. A device comprising a battery pack according to claim 16. In Article 17,
The above device,
A device that is a computer, laptop, smartphone, mobile phone, tablet PC, wearable electronic device, power tool, electric vehicle (EV), hybrid electric vehicle (HEV), plug-in hybrid electric vehicle (PHEV), or power storage device.

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