KR20170033542A - Secondary battery - Google Patents

Abstract

An embodiment of the present invention provides a secondary battery capable of preventing an anode tab group and a cathode tab group from being short-circuited. Also, the embodiment of the present invention provides the secondary battery without the limitation of the size and the formation position of the anode tab group and the cathode tab group. To this end, the secondary battery according to an embodiment of the present invention includes an electrode assembly which is composed of a first electrode plate, a second electrode plate, and a separator which is interposed between the first and second electrode plates, and an insulation member which includes a body part which is inserted into the center part of the electrode assembly and a head part which protrudes to the outside of one side of the electrode assembly.

Description

Secondary Battery {SECONDARY BATTERY}

One embodiment of the present invention relates to a secondary battery.

BACKGROUND ART A rechargeable battery is a battery capable of charging and discharging unlike a primary battery which can not be charged. In the case of a battery in which one battery cell is packed, a rechargeable battery is used in portable electronic equipment such as a mobile phone and a camcorder, BACKGROUND ART [0002] A large-capacity battery of a battery pack unit having dozens of battery packs is widely used as a power source for driving a motor such as a hybrid vehicle.

The secondary battery is manufactured in various shapes. Typical shapes include a cylindrical shape and a square shape, and an electrode assembly formed by interposing a separator, which is an insulator, between the positive and negative electrode plates and an electrolyte solution are built in the case.

The positive electrode plate and the negative electrode plate of the electrode assembly are respectively provided with a positive electrode tab and a negative electrode tab which are led out to the outside. In order to reduce the resistance in the case of the middle and large-sized secondary battery, Structure.

However, there is a problem that the positive electrode tab group and the negative electrode tab group are short-circuited to each other, and thus the position and size are limited.

An embodiment of the present invention provides a secondary battery capable of preventing a short circuit between a positive electrode tab group and a negative electrode tab group.

In addition, one embodiment of the present invention provides a secondary battery that does not limit the formation position and size of the positive electrode tab group and the negative electrode tab group.

The secondary battery according to an embodiment of the present invention includes an electrode assembly including a first electrode plate, a second electrode plate, a separator interposed between the first and second electrode plates, and a body portion And an insulator having a head portion protruding from one side of the electrode assembly.

Wherein the electrode assembly includes a first electrode tab extending from the first electrode plate to the one side, a second electrode tab extending from the second electrode plate to the first electrode tab and spaced apart from the first electrode tab, And the first electrode tab and the second electrode tab in the longitudinal direction of the long side may form an overlap region in which at least a part of the first electrode tab and the second electrode tab overlap with each other.

The insulating member may be a rectangular plate.

Wherein the first electrode tab and the second electrode tab have a first width and the overlap region has a second width equal to or less than the first width and the total width of the first electrode tab and the second electrode tab is equal to or greater than the first width, And the insulating member may have a fourth width that is equal to or greater than the second width and equal to or less than the third width.

The body portion of the insulating member may have a fifth width, and the head portion of the insulating member may be plate-shaped having a sixth width different from the fifth width.

Wherein the first electrode tab and the second electrode tab have a first width and the overlap region has a second width equal to or less than the first width and the total width of the first electrode tab and the second electrode tab is equal to or greater than the first width, And the sixth width of the head portion of the insulating member may be equal to or greater than the second width and equal to or less than the third width.

Wherein the electrode assembly has a first height, the first electrode tab and the second electrode tab have a second height, the body portion of the insulating member has a first height, and the head portion of the insulating member has a second height 3 < / RTI > height.

A through hole may be formed at the center of the body portion of the insulating member.

The body portion of the insulating member may have a first thickness, and the thickness of the head portion of the insulating member may gradually increase in the one direction.

The insulating member may be flame retardant.

The insulating member may be formed of any one of polyethylene (PE), polypropylene (PP), and polyimide (PI).

Wherein the first electrode tabs form a first electrode tab group composed of a plurality of electrode tabs extending from the first electrode plate to the one side and the second electrode tabs are formed of a plurality A second electrode tab group composed of an electrode tab of the first electrode tab may be formed.

The secondary battery according to an embodiment of the present invention can prevent a short circuit between the positive electrode tab group and the negative electrode tab group.

In addition, the secondary battery according to an embodiment of the present invention may not limit the formation position and size of the positive electrode tab group and the negative electrode tab group.

1 is a partially exploded perspective view illustrating an electrode assembly of a secondary battery according to an embodiment of the present invention.
2 is a perspective view showing the electrode assembly of FIG. 1;
3 is a front view showing the electrode assembly of FIG.
4 and 5 are partially exploded perspective views illustrating a secondary battery according to an embodiment of the present invention.
FIG. 6 is a partial front view of the secondary battery of FIG. 1;
7 is a perspective view illustrating an insulating member of a secondary battery according to another embodiment of the present invention.
FIG. 8 is a partial front view showing a secondary battery to which the insulating member of FIG. 7 is coupled.
9 is a perspective view illustrating an insulating member of a secondary battery according to another embodiment of the present invention.
10 is a perspective view illustrating an insulating member of a secondary battery according to another embodiment of the present invention.
FIG. 11 is a partial side sectional view showing a secondary battery to which the insulating member of FIG. 10 is coupled.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, so that those skilled in the art can easily carry out the present invention.

As used herein, the term "and / or" includes any and all combinations of one or more of the listed items. In addition, the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting of the invention. In addition, as used herein, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Furthermore, " comprise "and / or" comprising "as used herein specify the presence of stated steps, operations, elements, elements, numerical values and / But does not preclude the presence or addition of other steps, operations, elements, elements, numerical values and / or groups.

It is to be understood that, although the terms first and second are used herein to describe certain matters, it should be understood that they should not be construed as being limited to these terms. These terms are only used to distinguish one configuration from another.

FIG. 2 is a perspective view illustrating the electrode assembly of FIG. 1, and FIG. 3 is a front view of the electrode assembly of FIG. 1. FIG. And FIGS. 4 and 5 are partially exploded perspective views illustrating a secondary battery according to an embodiment of the present invention, and FIG. 6 is a partial front view illustrating the secondary battery of FIG.

Referring to FIGS. 1 to 6, a secondary battery according to an embodiment of the present invention includes an electrode assembly 100, a case 200, and an insulating member 300.

1 and 3, the electrode assembly 100 includes a first electrode plate 10, a second electrode plate 20, a separator 30, (40) and a second electrode tab group (50).

Specifically, the electrode assembly 100 includes a first electrode plate 10, a second electrode plate 20, and a separator 30 wound in a jelly roll type. The separator 30 is disposed between the first electrode plate 10 and the second electrode plate 20 so as to insulate the first electrode plate 10 from the second electrode plate 20 and is formed of an insulating material. The electrode assembly 100 has a first height H1 that is the height of the first electrode plate 10, the second electrode plate 20, and the separator 30.

Here, the first electrode plate 10 may serve as an anode, and the second electrode plate 20 may serve as a cathode. However, the present invention is not limited to this, and the polarity of each electrode plate may be changed. For convenience of explanation, it is assumed that the first electrode plate 10 is a positive electrode plate and the second electrode plate 20 is a negative electrode plate in the embodiments of the present invention.

The first electrode plate 10 includes a positive electrode active material layer 11 applied on both surfaces of a positive electrode current collector made of a thin metal plate having excellent conductivity, for example, aluminum foil. As the cathode active material of the cathode active material layer 11, a chalcogenide compound is used. Examples of the cathode active material include LiCoO ₂ , LiMn ₂ O ₄ , LiNiO ₂ , LiNi _1-x Co _x O ₂ (0 <x <1 ), LiMnO _2, and the like are used, but the material is not limited in this embodiment. The first electrode plate 10 includes a first electrode uncoated portion 12 to which the positive electrode active material layer 11 is not applied.

The first electrode uncoated portion 12 is formed as a plurality of spaced apart portions extending from the first electrode plate 10 to one side (upper portion). Here, the first electrode uncoated portion 12 may be formed of the first electrode tab 12 by removing an unnecessary region through a process such as punching.

The second electrode plate 20 includes a negative electrode active material layer 21 coated on both surfaces of a negative electrode collector made of a conductive metal thin plate such as copper (Cu) or nickel (Ni) foil. The negative electrode active material of the negative electrode active material layer 21 may be a carbonaceous material, Si, Sn, tin oxides, composite tin alloys, transition metal oxides, lithium metal nitrides or lithium metal oxides , But the material is not limited in this embodiment. The second electrode plate 20 includes a second electrode uncoated portion 22 to which the negative active material layer 21 is not applied.

The second electrode uncoated portion 22 is formed as a plurality of spaced apart portions extending from the second electrode plate 20 to one side (upper portion). Here, the second electrode uncoated portion 22 may be formed of the first electrode tab 22 by removing an unnecessary region through a process such as punching.

The separator 30 prevents a short between the first electrode plate 10 and the second electrode plate 20 and enables only the charge of the secondary battery, for example, lithium ions, Polyethylene, polypropylene, and a group consisting of co-polymer of polyethylene and polypropylene. However, the material is not limited in this embodiment. It is preferable that the separator 30 is formed to have a width larger than that of the first electrode plate 10 and the second electrode plate 20 by a short circuit between the first electrode plate 10 and the second electrode plate 20 .

The first electrode tab group 40 and the second electrode tab group 50 are all formed to extend in the same direction of the electrode assembly 100. In the drawing, the first electrode tab group 40 and the second electrode tab group 50 are formed to face the upper (one side) of the electrode assembly 100.

The first electrode tab group 40 includes a plurality of first electrode tabs 12 formed of electrode tabs. In addition, the second electrode tab group 50 includes a plurality of second electrode tabs 22 formed of electrode tabs.

The first electrode tab group 40 and the second electrode tab group 50 may have the same first width W1 and second height H2 and the first electrode tab group 40 and the second electrode tab group 50 may have the same first width W1 and second height H2, The side surfaces of the electrode tabs 22 may be formed parallel to each other.

The first electrode tab group 40 and the second electrode tab group 50 are formed to face each other with respect to the center C of the electrode assembly 100. Here, the center portion C of the electrode assembly 100 is a winding center portion, and a mandrel (not shown) is missing after winding.

The first electrode tab group 40 and the second electrode tab group 50 form an overlap region 60 in which at least a portion of the first electrode tab group 40 and the second electrode tab group 50 overlap with each other when viewed from the front side of the electrode assembly 100 do.

Here, the first electrode tab group 40 and the second electrode tab group 50 each have a first width W1, and the overlap region 60 has a second width W2 , The first electrode tab group 40 and the second electrode tab group 50 all have a third width W3.

4 to 6, an electrode assembly 100 is inserted into a case 200, and an insulating member 300 is inserted into a central portion C of the electrode assembly 100.

The case 200 may be formed of a conductive metal such as aluminum, aluminum alloy, nickel plated steel, or a non-conductive material. The case 200 may have a substantially hexahedron shape having an upper opening to accommodate the electrode assembly 100 and the electrolyte solution. .

The insulating member 300 has a rectangular plate shape and includes a body portion 310 and a head portion 320. The insulating member 300 may be made of any one of insulating and flame-retardant materials such as polyethylene (PE), polypropylene (PP), and polyimide (PI).

The body 310 has a first height H1 that is substantially the same as the electrode assembly 100 and is inserted into the central portion C of the electrode assembly 100 and is smaller than the width and thickness of the central portion C And has a fourth width W4 and a first thickness T1.

The head 320 extends from the body 310 to the upper side and protrudes to the outside of the electrode assembly 100. That is, the head 320 is positioned between the first electrode tab group 40 and the second electrode tab group 50.

The head 320 has a third height H3 that is less than or equal to the second height H2 of the first electrode tab group 40. [ That is, the head 320 does not protrude above the first electrode tab group 40 and the second electrode tab group 50.

The head portion 320 has a fourth width W4 that is greater than or equal to the second width W2 of the overlap region 60. [ Of course, the fourth width W4 of the head 320 is the same as the fourth width W4 of the body 310. The head 320 may be divided into a first electrode tab group 40 and a second electrode tab group 50 in the overlap region 60 of the first electrode tab group 40 and the second electrode tab group 50. [ ) From being electrically and physically contacted. The first electrode tab group 40 and the second electrode tab group 50 can be freely formed without being limited in their forming positions and sizes due to the head 320 of the insulating member 300 interposed therebetween have.

The fourth width W4 of the head 320 may be smaller than or equal to a third width W3 of the first electrode tab group 40 and the second electrode tab group 50, Or more.

Next, a secondary battery according to another embodiment of the present invention will be described with reference to FIGS. 7 and 8. FIG.

FIG. 7 is a perspective view illustrating an insulating member of a secondary battery according to another embodiment of the present invention, and FIG. 8 is a partial front view illustrating a secondary battery having the insulating member of FIG. 7 coupled thereto.

Referring to FIGS. 4 and 7, the secondary battery according to another embodiment of the present invention differs from the secondary battery according to the embodiment in the configuration of the insulating member 400. Therefore, a secondary battery according to another embodiment of the present invention will be described below with reference to the insulating member 400. The secondary battery according to another embodiment of the present invention uses the same reference numerals as those of the secondary battery according to FIG. 4, and detailed description thereof will be omitted.

The insulating member 400 is a plate having a convex shape and includes a body portion 410 and a head portion 420. The insulating member 400 may be made of any one of insulating and flame-retardant materials such as polyethylene (PE), polypropylene (PP), and polyimide (PI).

The body portion 410 has a first height H1 that is substantially the same as the electrode assembly 100 and is inserted into the central portion C of the electrode assembly 100. The body portion 410 has a fifth width W5, (T1). Here, the fifth width W5 may be equal to the fourth width W4 described above. However, in another embodiment of the present invention, the fifth width W5 of the body portion 410 may be equal to the fourth width W4, Width, and is not particularly limited thereto.

The head part 420 extends from the body part 410 to the upper side and protrudes to the outside of the electrode assembly 100. That is, the head portion 420 is positioned between the first electrode tab group 40 and the second electrode tab group 50.

The head portion 420 has a third height H3 that is less than or equal to the second height H2 of the first electrode tab group 40. [ That is, the head portion 420 does not protrude above the first electrode tab group 40 and the second electrode tab group 50.

The head portion 420 has a sixth width W6 that is greater than or equal to the second width W2 of the overlap region 60. [ The head 320 may be divided into a first electrode tab group 40 and a second electrode tab group 50 in the overlap region 60 of the first electrode tab group 40 and the second electrode tab group 50. [ ) From being electrically and physically contacted. The first electrode tab group 40 and the second electrode tab group 50 can be freely formed without being restricted in the position and size of the formation thereof due to the head portion 420 of the insulating member 400 interposed therebetween have.

The sixth width W6 of the head part 420 is different from the fifth width W5 of the body part 410 and the body part 410 and the head part 420 are separately formed can do. That is, since the unnecessary region can be removed from the insulating member 400, there is an advantage that the weight of the secondary battery can be reduced.

7 and 8, the fifth width W5 of the body portion 410 is formed to be larger than the sixth width W6 of the head portion 420 so that the insulating member 400 has a "convex" shape The fifth width W5 of the body portion 410 may be smaller than the sixth width W6 of the head portion 420 so that the insulating member 400 may have a T shape.

Next, a secondary battery according to another embodiment of the present invention will be described with reference to FIG.

9 is a perspective view illustrating an insulating member of a secondary battery according to another embodiment of the present invention.

4 and 9, the secondary battery according to another embodiment of the present invention differs from the secondary battery according to the embodiment in the configuration of the insulating member 500. Therefore, a secondary battery according to another embodiment of the present invention will be described below with reference to the insulating member 500. The secondary battery according to another embodiment of the present invention uses the same reference numerals as those of the secondary battery according to FIG. 4, and a detailed description thereof will be omitted.

The insulating member 500 is a rectangular plate and includes a body portion 510 and a head portion 520. The insulating member 500 may be made of any one of insulating and flame-retardant materials such as polyethylene (PE), polypropylene (PP), and polyimide (PI).

The body 510 has a first height H1 that is substantially the same as the electrode assembly 100 and is inserted into the central portion C of the electrode assembly 100. [

Here, a through hole 530 is formed in the center of the body 510. The electrode assembly 100 can be inserted into the center of the wound electrode assembly 100 to compensate for the expansion of the first electrode plate 10 and the second electrode plate 20 during charging / discharging. In addition, there is an advantage that the weight of the entire secondary battery can be reduced by the through hole 530 formed at the center of the body portion 510.

The head 520 extends from the body 510 to the upper side and protrudes to the outside of the electrode assembly 100. That is, the head 520 is positioned between the first electrode tab group 40 and the second electrode tab group 50.

Here, the head 520 has a third height H3 that is less than or equal to the second height H2 of the first electrode tab group 40. That is, the head 520 does not protrude above the first electrode tab group 40 and the second electrode tab group 50.

The head portion 520 has a fourth width W4 that is greater than or equal to the second width W2 of the overlap region 60. [ Of course, the fourth width W4 of the head 520 is the same as the fourth width W4 of the body 310. The head 520 may be positioned between the first electrode tab group 40 and the second electrode tab group 50 in the overlap region 60 between the first electrode tab group 40 and the second electrode tab group 50. [ ) From being electrically and physically contacted. The first electrode tab group 40 and the second electrode tab group 50 can be freely formed without being limited in their forming positions and sizes due to the head portion 520 of the insulating member 500 interposed therebetween have.

The fourth width W4 of the head 520 is formed to be smaller than or equal to a third width W3 which is the overall width of the first electrode tab group 40 and the second electrode tab group 50, Or more.

Next, a secondary battery according to another embodiment of the present invention will be described with reference to FIGS. 10 and 11. FIG.

FIG. 10 is a perspective view illustrating an insulating member of a secondary battery according to another embodiment of the present invention, and FIG. 11 is a partial side sectional view illustrating a secondary battery to which the insulating member of FIG. 10 is coupled.

4 and 10, the secondary battery according to another embodiment of the present invention differs from the secondary battery according to the embodiment in the configuration of the insulating member 600. [ Therefore, a secondary battery according to another embodiment of the present invention will be described below with reference to the insulating member 600. The secondary battery according to another embodiment of the present invention uses the same reference numerals as those of the secondary battery according to FIG. 4, and a detailed description thereof will be omitted.

The insulating member 600 includes a body portion 610 and a head portion 620. The insulating member 600 may be made of any one of insulating and flame-retardant materials such as polyethylene (PE), polypropylene (PP), and polyimide (PI).

The body portion 610 has a rectangular plate shape and is substantially inserted into the central portion C of the electrode assembly 100 and has a first height H1 that is the same as the electrode assembly 100, And a first thickness T1.

The head portion 620 extends from the body portion 610 to the upper side and protrudes out of the electrode assembly 100. That is, the head 620 is positioned between the first electrode tab group 40 and the second electrode tab group 50.

The head 620 has a third height H3 that is less than or equal to the second height H2 of the first electrode tab group 40. [ That is, the head 620 does not protrude above the first electrode tab group 40 and the second electrode tab group 50.

The head portion 620 has a fourth width W4 that is greater than or equal to the second width W2 of the overlap region 60. [ Of course, the fourth width W4 of the head portion 620 is the same as the fourth width W4 of the body portion 610. [ The head 620 may be positioned between the first electrode tab group 40 and the second electrode tab group 50 in the overlap region 60 between the first electrode tab group 40 and the second electrode tab group 50. [ ) From being electrically and physically contacted. The first electrode tab group 40 and the second electrode tab group 50 can be formed freely without being limited in their forming positions and sizes due to the head portion 620 of the insulating member 600 interposed between the first electrode tab group 40 and the second electrode tab group 50. [ have.

The fourth width W4 of the head 620 is formed to be smaller than or equal to a third width W3 which is the overall width of the first electrode tab group 40 and the second electrode tab group 50, Or more.

In addition, the thickness of the head portion 620 gradually increases toward the upper side. That is, one end of the head portion 620 has a second thickness T2 that is thicker than the first thickness T1 of the body portion 610. Here, when the body portion 610 of the insulating member 600 is inserted into the center portion C of the electrode assembly 100, the head portion 620 contacts the first electrode tab group 40 and the second electrode tab group 50). The first electrode tab group 40 and the second electrode tab group 50 are bent in opposite directions so that the first electrode tab group 40 and the second electrode tab group 50 are electrically and physically It is possible to more effectively prevent contact.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. It is.

10; A first electrode plate 20; The second electrode plate
30; Separator 40; The first electrode tab group
50; The second electrode tab group
100; An electrode assembly 200; case
300, 400, 500, 600; Insulating members 310, 410, 510, 610; Body portion
320, 420, 520, 620; Head portion 530; Passage

Claims (12)

An electrode assembly comprising a first electrode plate, a second electrode plate, and a separator interposed between the first and second electrode plates; And
And an insulation member formed of a body portion inserted into a center portion of the electrode assembly and a head portion protruding from one side of the electrode assembly. The method according to claim 1,
The electrode assembly
A first electrode tab extending from the first electrode plate to the one side;
A second electrode tab extending from the second electrode plate to the first electrode tab and spaced apart from the first electrode tab; And
Further comprising a long side surface and a short side surface in a direction perpendicular to the one direction,
Wherein the first electrode tabs and the second electrode tabs form overlapping areas in which at least a part of the first electrode tabs and the second electrode tabs overlap with each other in the longitudinal direction of the long side. 3. The method of claim 2,
Wherein the insulating member is a quadrangular plate. The method of claim 3,
Wherein the first electrode tab and the second electrode tab have a first width,
The overlap region has a second width that is less than or equal to the first width,
Wherein a total width of the first electrode tab and the second electrode tab is a third width greater than the first width,
Wherein the insulating member has a fourth width that is equal to or greater than the second width and equal to or less than the third width. 3. The method of claim 2,
The body portion of the insulating member has a fifth width,
Wherein the head portion of the insulating member is of a plate type having a sixth width different from the fifth width. 6. The method of claim 5,
Wherein the first electrode tab and the second electrode tab have a first width,
The overlap region has a second width that is less than or equal to the first width,
Wherein a total width of the first electrode tab and the second electrode tab is a third width greater than the first width,
Wherein a sixth width of the head portion of the insulating member is not less than a second width and not more than a third width. 3. The method of claim 2,
Wherein the electrode assembly has a first height,
Wherein the first electrode tab and the second electrode tab have a second height,
Wherein the body portion of the insulating member has a first height,
Wherein the head portion of the insulating member has a third height that is equal to or less than a second height. 3. The method of claim 2,
And a through hole is formed at the center of the body portion of the insulating member. 3. The method of claim 2,
Wherein the body portion of the insulating member has a first thickness,
Wherein the thickness of the head portion of the insulating member gradually increases in the one direction. 3. The method of claim 2,
Wherein the insulating member is flame-retardant. 11. The method of claim 10,
Wherein the insulating member is formed of any one of polyethylene (PE), polypropylene (PP), and polyimide (PI). 3. The method of claim 2,
The first electrode tab may form a first electrode tab group composed of a plurality of electrode tabs extending from the first electrode plate to the one side,
Wherein the second electrode tab forms a second electrode tab group composed of a plurality of electrode tabs extending from the second electrode plate to the one side.

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