Rechargeable batteries

Abstract

An exemplary embodiment of the present invention provides a rechargeable battery including a plurality of separate electrode unit bodies, each electrode unit body including: a first separator; a first electrode plate and a second electrode plate of a first electrode, arranged to be separated from each other on one surface of the first separator; a second separator, arranged on the first electrode plate and the second electrode plate of the first electrode; and a first electrode plate of a second electrode, corresponding to the first electrode plate of the first electrode and arranged on one surface of the second separator, wherein the first separator and the second separator are folded between the first electrode plate and the second electrode plate of the first electrode.

Description

[0001] This application is a divisional application of the invention patent application "Rechargeable battery and manufacturing method thereof" with application date of May 19, 2017 and application number 201710358390.3. Technical Field

[0002] The present disclosure relates to a rechargeable battery. More particularly, the present disclosure relates to a rechargeable battery having an electrode assembly formed from a unit body formed by stacking and folding electrodes and separators in a continuous process. Background Art

[0003] Unlike primary batteries, rechargeable batteries can be repeatedly charged and discharged. Low-capacity rechargeable batteries are used in small portable electronic devices such as mobile phones, laptops, and video cameras, while large-capacity rechargeable batteries are used as power sources for driving electric motors, such as those used in hybrid vehicles.

[0004] For example, a rechargeable battery includes an electrode assembly that undergoes charge and discharge, and a bag or case that contains the electrode assembly and an electrolyte solution. The electrode assembly can be made into a stacked type, a spiral-wound type, and a stacked spiral-wound hybrid type according to the structure of the electrodes and separators.

[0005] In stacked electrode assemblies, it is difficult to align the electrodes and separators, complicating the manufacturing process. When a spirally wound electrode assembly is deformed into a plate shape after spiral winding and inserted into a pouch, a large amount of empty space is formed within the pouch, degrading capacity.

[0006] The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. Summary of the Invention

[0007] The present invention provides a rechargeable battery that can easily increase capacity while facilitating manufacturing processes, that is, provides a rechargeable battery that achieves production efficiency and quality stability.

[0008] A rechargeable battery according to an exemplary embodiment of the present invention includes: an electrode assembly including at least a unit body, the unit body including a first region and a second region and an electrode plate of a first electrode and an electrode plate of a second electrode, the first region and the second region being divided based on a folding center at which a separator including at least two facing sheets is folded, wherein the electrode plates of the first electrode and the electrode plates of the second electrode are alternately stacked while a separator is placed in each of the first region and the second region; and a shell accommodating the electrode assembly and an electrolyte solution.

[0009] The unit cell may include the same number of electrode plates of the first electrode, electrode plates of the second electrode, and separators.

[0010] The separator may include an outer sheet disposed at the outermost side of the two sheets arranged to be folded, and an inner sheet disposed at the innermost side of the two sheets arranged to be folded.

[0011] The first electrode may include a first / first electrode plate disposed in the first region between the outer sheet and the inner sheet and a first / second electrode plate disposed in the second region.

[0012] The second electrode may include: a second / first electrode plate corresponding to the first / first electrode plate and disposed in the first region on the outside of the outer sheet; and a second / second electrode plate corresponding to the first / second electrode plate and disposed in the second region on the inside of the inner sheet.

[0013] By folding the outer sheet and the inner sheet, the unit body can form a unit battery in the first area by the second / first electrode plate, the outer sheet, the first / first electrode plate and the inner sheet, and can form a unit battery in the second area by the second / second electrode plate, the inner sheet, the first / second electrode plate and the outer sheet, and can also form a unit battery between the first area and the second area by the first / first electrode plate, the inner sheet and the second / second electrode plate.

[0014] The electrode assembly may be formed by stacking and electrically connecting a plurality of unit cells.

[0015] The electrode assembly may further include an outermost unit body disposed at one outermost side of the electrode assembly.

[0016] The outermost unit cell may include the same number of electrode plates of the first electrode and separators, and may include electrode plates of the second electrode in a number less than one of the electrode plates of the first electrode.

[0017] The separator in the outermost unit body may include an outer sheet arranged at the outermost side of two sheets arranged to be folded and an inner sheet arranged at the innermost side of the two sheets arranged to be folded, the first electrode may include a first / first electrode plate located in the first region between the outer sheet and the inner sheet and a first / second electrode plate arranged in the second region, the second electrode may include a second / second electrode plate corresponding to the first / first electrode plate and the first / second electrode plate, the second / second electrode plate being located on the inner side of the folded inner sheet and arranged in the second region.

[0018] The outermost unit body can form a unit battery in the second area by folding the outer sheet and the inner sheet, consisting of the second / second electrode plate, the inner sheet, the first / second electrode plate and the outer sheet, and can form a unit battery between the first area and the second area by folding the first / first electrode plate, the inner sheet and the second / second electrode plate.

[0019] The outermost unit cell may be formed by disposing separators on both surfaces of the first electrode, the separators may include an outer sheet and an inner sheet, and the first electrode may include a first / third electrode plate disposed between the outer sheet and the inner sheet.

[0020] The separator may include an outer sheet disposed at the outermost side of three sheets arranged to be folded, an inner sheet disposed at the innermost side of the three folded sheets, and a middle sheet disposed between the outer sheet and the inner sheet.

[0021] The first electrode may include a first / first electrode plate disposed in a first region between the outer sheet and the middle sheet, a first / second electrode plate disposed in a second region, and a first / fourth electrode plate disposed within the folded inner sheet.

[0022] The second electrode may include: a second / first electrode plate, corresponding to the first / first electrode plate and arranged on the outside of the outer sheet in the first region; a second / fifth electrode plate, corresponding to the first / first electrode plate and the first / fourth electrode plate and arranged in the first region between the middle sheet and the inner sheet; and a second / sixth electrode plate, corresponding to the first / second electrode plate and the first / fourth electrode plate and arranged in the second region.

[0023] By folding the outer sheet, the middle sheet and the inner sheet, the unit body can form two unit batteries in the first area by the second / first electrode plate, the outer sheet, the first / first electrode plate, the middle sheet, the second / fifth electrode plate and the inner sheet; can form two unit batteries in the second area by the first / fourth electrode plate, the inner sheet, the second / sixth electrode plate, the middle sheet, the first / second electrode plate and the outer sheet; and can also form one unit battery between the first area and the second area by the second / fifth electrode plate, the inner sheet and the first / fourth electrode plate.

[0024] The electrode assembly may be formed by stacking and electrically connecting a plurality of unit cells.

[0025] The electrode assembly may also include an outermost unit body arranged at the outermost side of the electrode assembly, and the outermost unit body can form a unit battery in the second region by folding the outer sheet and the inner sheet with the second / second electrode plate, the inner sheet, the first / second electrode plate and the outer sheet, and can form a unit battery between the first region and the second region by the first / first electrode plate, the inner sheet and the second / second electrode plate.

[0026] The electrode assembly may further include an outermost unit body arranged at an outermost side of the electrode assembly. The outermost unit body may be formed by arranging separators at both surfaces of the first electrode. The separators may include an inner sheet and an outer sheet. The first electrode may include a first / third electrode plate arranged between the outer sheet and the inner sheet.

[0027] The outer sheet may further include an extension portion, which may coat the outermost sides of the plurality of stacked unit cells and may be secured by a terminating tape.

[0028] The second electrode can be arranged between the middle sheet and the inner sheet, and can include: a second / fifth electrode plate, corresponding to the first / first electrode plate and the first / fourth electrode plate and arranged in the first area; a second / sixth electrode plate, corresponding to the first / second electrode plate and the first / fourth electrode plate and arranged in the second area.

[0029] By folding the outer sheet, the middle sheet and the inner sheet, the unit body can form a unit battery in the first area by the outer sheet, the first / first electrode plate, the middle sheet, the second / fifth electrode plate and the inner sheet, can form two unit batteries in the second area by the first / fourth electrode plate, the inner sheet, the second / sixth electrode plate, the middle sheet, the first / second electrode plate and the outer sheet, and can also form a unit battery between the first area and the second area by the second / fifth electrode plate, the inner sheet and the first / fourth electrode plate.

[0030] In the electrode assembly, the unit bodies may be stacked at one outermost side of the unit bodies to be electrically connected to the other unit bodies.

[0031] The electrode assembly may further include an additional unit body added at the outside of the outermost unit body, the additional unit body may include a separator as an outer sheet arranged outside the second electrode, and the second electrode may include a second / third electrode plate arranged between the outer sheet of the additional unit body and the outer sheet of the outermost unit body.

[0032] The outermost unit body may include an outer sheet arranged at the outermost side and an inner sheet arranged at the innermost side, the first electrode may include a first / first electrode plate and a first / second electrode plate arranged between the outer sheet and the inner sheet, and the second electrode may include a second / second electrode plate corresponding to the first / first electrode plate and the first / second electrode plate and arranged on the inner side of the folded inner sheet.

[0033] The outermost unit body may include an outer sheet arranged at the outermost side, an inner sheet arranged at the innermost side, and an intermediate sheet arranged between the outer sheet and the inner sheet. The first electrode may include a first / first electrode plate and a first / second electrode plate arranged between the outer sheet and the intermediate sheet, and a first / fourth electrode plate arranged between the folded inner sheets. The second electrode may include: a second / fifth electrode plate, which is arranged between the intermediate sheet and the inner sheet corresponding to the first / first electrode plate and the first / fourth electrode plate; and a second / sixth electrode plate, which is arranged corresponding to the first / second electrode plate and the first / fourth electrode plate.

[0034] According to an exemplary embodiment of the present invention, an electrode assembly is formed from at least one unit body in which a plurality of separators face each other and are folded, and electrode plates of a first electrode and a second electrode are alternately stacked in each of the first region and the second region, making it possible to easily increase the capacity of the battery. The unit body is formed by arranging the electrode plates of the first electrode and the second electrode between the folded separators, making it possible to achieve production efficiency and quality stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is an exploded perspective view of a rechargeable battery according to a first exemplary embodiment of the present invention.

[0036] Figure 2 It is a stack of electrode plates and separators to form a Figure 1 A cross-sectional view of the state of a unit body of an electrode assembly.

[0037] Figure 3 By folding Figure 2 A cross-sectional view of a unit body formed by partitions in a stacked state.

[0038] Figure 4 By stacking Figure 3 A cross-sectional view of an electrode assembly formed of a unit body.

[0039] Figure 5 is an electrode assembly of a rechargeable battery according to a second exemplary embodiment of the present invention (including an outermost unit cell and Figure 3 A cross-sectional view of a unit body).

[0040] Figure 6 It is a stack of electrode plates and separators to form a Figure 5 A cross-sectional view of the state of the outermost unit body of the electrode assembly.

[0041] Figure 7 By folding Figure 6 A cross-sectional view of the outermost unit body formed by the stacked partitions.

[0042] Figure 8 is an electrode assembly (including an outermost unit cell and Figure 3 A cross-sectional view of a unit body).

[0043] Figure 9 is applied to Figure 8 A cross-sectional view of the outermost unit body (including the electrode plate and the separator) of the electrode assembly.

[0044] Figure 10is a cross-sectional view of a state in which electrode plates and separators are stacked to form a unit body of an electrode assembly applied to a rechargeable battery according to a fourth exemplary embodiment of the present invention.

[0045] Figure 11 By folding Figure 10 A cross-sectional view of a unit body formed by stacked separators.

[0046] Figure 12 By stacking Figure 11 A cross-sectional view of an electrode assembly formed of a unit body.

[0047] Figure 13 is an electrode assembly of a rechargeable battery according to a fifth exemplary embodiment of the present invention (including Figure 11 The unit body and Figure 7 A cross-sectional view of the outermost unit body).

[0048] Figure 14 is an electrode assembly of a rechargeable battery according to a sixth exemplary embodiment of the present invention (including Figure 11 The unit body and Figure 9 A cross-sectional view of the outermost unit body).

[0049] Figure 15 is a rechargeable battery according to a sixth exemplary embodiment of the present invention (by stacking Figure 3 The unit body and Figure 3 A cross-sectional view of an electrode assembly (formed by a variation of a unit body).

[0050] Figure 16 is a rechargeable battery according to a seventh exemplary embodiment of the present invention (by stacking Figure 3 The unit body and Figure 3 A cross-sectional view of an electrode assembly (formed by a variation of a unit body).

[0051] Figure 17 is a unit body (eg, Figure 10 A cross-sectional view of the stacked state of a modified unit body).

[0052] Figure 18 By folding Figure 17 The stacked partitions form a unit body ( Figure 11 A cross-sectional view of a modified unit body).

[0053] Figure 19 By stacking Figure 18 The electrode assembly formed by the unit body ( Figure 12 The changes in the electrode assembly, i.e., Figure 11 The unit body and Figure 18 A cross-sectional view of a unit body).

[0054] Figure 20 is a unit body ( Figure 3 and Figure 7 The unit body and Figure 9 A cross-sectional view of the outermost unit body of the change in the separated state.

[0055] Figure 21 By stacking Figure 20 The electrode assembly formed by the unit body ( Figure 8 A cross-sectional view of a modified electrode assembly).

[0056] Figure 22 is a unit body ( Figure 11 and Figure 18 The unit body and Figure 9 A cross-sectional view of a state in which the outermost unit body of the variant is separated.

[0057] Figure 23 By stacking Figure 22 The electrode assembly formed by the unit body ( Figure 14 A cross-sectional view of a modified electrode assembly). DETAILED DESCRIPTION

[0058] Hereinafter, the present invention will be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the present invention are shown. As will be appreciated by those skilled in the art, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. The drawings and description should be regarded as illustrative in nature and not restrictive. Throughout the specification, the same reference numerals represent the same elements.

[0059] Figure 1 is an exploded perspective view of a rechargeable battery according to a first exemplary embodiment of the present invention. Figure 1 A rechargeable battery according to a first exemplary embodiment of the present invention includes: an electrode assembly 2 including at least one unit body 1; a case 3 accommodating the electrode assembly 2 and an electrolyte solution; and lead tabs 4 and 5 electrically connected to the electrode assembly 2 and pulled out of the case 3.

[0060] In the first exemplary embodiment, a pouch-type rechargeable battery whose case is formed as a pouch is described, but the present invention can also be applied to a can-type rechargeable battery (not shown) whose case is in the form of a rectangular can.

[0061] Furthermore, the first exemplary embodiment describes the rechargeable battery in which the lead tabs 4 and 5 are pulled out on one side of the case 3 , but the present invention may be applied to a rechargeable battery (not shown) in which the lead tabs are pulled out on both sides of the case.

[0062] Figure 2 It is a stack of electrode plates and separators to form a Figure 1 A cross-sectional view of the state of the unit body of the electrode assembly, Figure 3 By folding Figure 2 A cross-sectional view of a unit body formed by partitions in a stacked state.

[0063] Reference Figure 2 and Figure 3 The unit cell 1 includes a plurality of separators 30 folded to face each other, and a first electrode 10 (eg, a negative electrode) and a second electrode 20 (eg, a positive electrode) formed of at least one electrode sheet and disposed between the separators 30 .

[0064] The unit cell 1 may be provided with the same number of electrode plates of the first electrode 10, the second electrode 20, and the separator 30. As an example, in the unit cell 1, the number of electrode plates of the first electrode 10, the number of electrode plates of the second electrode 20, and the separator 30 are respectively provided in two.

[0065] The partition 30 is formed of two sheets and includes a first area AR1 and a second area AR2 that are folded to face each other and are divided based on the folding center therebetween. As an example, the partition 30 includes an outer sheet 31 that is arranged on the outside in the folded state and an inner sheet 32 that is arranged on the inside in the folded state.

[0066] Electrode plates forming the first electrode 10 and electrode plates forming the second electrode 20 are alternately stacked while placing the outer sheet 31 and the inner sheet 32 in the first and second regions AR1 and AR2 , thereby forming a unit cell undergoing charge and discharge.

[0067] As an example, the first electrode 10 includes a first / first electrode plate 11 disposed in a first region AR1 between an outer sheet 31 and an inner sheet 32 and a first / second electrode plate 12 disposed in a second region AR2 (see FIG. Figure 2 ).

[0068] The second electrode 20 includes a second / first electrode plate 21, which is arranged in the first area AR1 and corresponds to the first / first electrode plate 11 and is located outside the outer sheet 31; a second / second electrode plate 22, which is arranged in the second area AR2 and corresponds to the first / second electrode plate 12 and is located inside the inner sheet 32 (refer to FIG. Figure 2 and Figure 3 ).

[0069] By arranging the first / first electrode plate 11 and the first / second electrode plate 12 and the second / first electrode plate 21 and the second / second electrode plate 22 on the inner and outer sides of the outer sheet 31 and the inner sheet 32, and folding the outer sheet 31 and the inner sheet 32 with reference to the folding center to manufacture the unit body 1, the separator 30 can be easily aligned with the first electrode 10 and the second electrode 20 in the manufacturing process of the unit body 1.

[0070] Reference Figure 3 The unit cell 1 forms one unit cell in the first area AR1 , one unit cell in the second area AR2 , and one unit cell between the first area AR1 and the second area AR2 by folding the outer sheet 31 and the inner sheet 32 .

[0071] That is, the second / first electrode plate 21, the outer sheet 31, the first / first electrode plate 11, and the inner sheet 32 form a unit cell in the first area AR1. The second / second electrode plate 22, the inner sheet 32, the first / second electrode plate 12, and the outer sheet 31 form a unit cell in the second area AR2. The first / first electrode plate 11 and the inner sheet 32 of the first area AR1 and the second / second electrode plate 22 of the second area AR2 form a unit cell between the first area AR1 and the second area AR2.

[0072] Figure 4 By stacking Figure 3 A cross-sectional view of an electrode assembly formed by a unit body. Figure 1 and Figure 4 , the electrode assembly 2 is formed by a plurality of unit bodies 1 to be electrically connected. As an example, the unit bodies 1 can be electrically connected to each other through lead tabs 4 and 5 (refer to Figure 1 ).

[0073] Since the electrode assembly 2 is formed by stacking the unit bodies 1, it is possible to promote an increase in battery capacity while facilitating a manufacturing process of the electrode assembly 2. That is, the unit body 1 can improve production efficiency and quality stability of the electrode assembly 2 and the rechargeable battery.

[0074] Refer again Figure 1 The electrode plates of the first electrode 10 and the second electrode 20 each include a coated region where the active material is applied to a current collector formed of a metal (Cu, Al) thin plate, and an uncoated region where the current collector is not coated with the active material and is exposed. Lead tabs 4 and 5 are connected to the uncoated regions of the electrode plates to be drawn outside the case 3.

[0075] As an example, the case 3 is formed as a flexible bag and includes a first outer portion 301 and a second outer portion 302 that accommodate the electrode assembly 2 and face each other. The first outer portion 301 and the second outer portion 302 are heat-sealed along the outer portion of the constructed electrode assembly 2 at a predetermined width. Although not shown, the case can be formed by forming and heat-sealing the first outer portion and the second outer portion having the same shape as the first outer portion.

[0076] The lead tabs 4 and 5 are pulled out of the housing 3 between the first outer portion 301 and the second outer portion 302 while inserting an insulating member (not shown). For example, the housing 3 includes an inner sheet S1, an outer sheet S3, and a metal sheet S2. The first outer portion 301 and the second outer portion 302 can be formed of the inner sheet S1, the outer sheet S3, and the metal sheet S2 in the same laminated structure.

[0077] The inner sheet S1 forms the inner surface of the housing 3 and can be formed from a polymer sheet for effective insulation and heat sealing. The outer sheet S3 forms the outer surface of the housing 3 and can be formed from a polyethylene terephthalate (PET) sheet, a nylon sheet, or a PET-nylon composite sheet for effective protection. The metal sheet S2 is disposed between the inner sheet S1 and the outer sheet S3 and can be formed from an aluminum sheet to provide mechanical integrity to the housing 3.

[0078] Next, various exemplary embodiments of the present invention will be described. When comparing the following exemplary embodiments with the first exemplary embodiment and the above exemplary embodiments, descriptions of the same configurations are omitted, and different configurations will be described.

[0079] Figure 5 is an electrode assembly of a rechargeable battery according to a second exemplary embodiment of the present invention (including an outermost unit cell and Figure 3 Cross-sectional view of the unit body). Figure 5 , the electrode assembly 6 applied to the rechargeable battery according to the second exemplary embodiment further includes an outermost unit cell 61 provided at one outermost side. That is, the electrode assembly 6 is stacked Figure 3 The stack structure is formed by stacking a plurality of unit cells 1 (two unit cells 1 as an example) and stacking an outermost unit cell 61 at the outermost side of one side.

[0080] Figure 6 It is a stack of electrode plates and separators to form a Figure 5 A cross-sectional view of the state of the outermost unit body of the electrode assembly, Figure 7 By folding Figure 6 A cross-sectional view of the outermost unit body formed by the stacked partitions.

[0081] Reference Figure 6 and Figure 7The outermost unit cell 61 includes the same number of electrode plates of the first electrode 10 and the separator 30, and includes one electrode plate of the second electrode 20 less than the number of electrode plates of the first electrode 10. As an example, in the outermost unit cell 61, two electrode plates of the first electrode 10, two separators 30, and one electrode plate of the second electrode 20 are provided.

[0082] In the outermost unit cell 61, the partition 30 includes two sheets arranged facing each other and folded relative to the folding center, the first area AR1 and the second area AR2. As an example, the partition 30 includes an outer sheet 31 arranged outside in the folded state and an inner sheet 32 arranged inside in the folded state.

[0083] As an example, the first electrode 10 includes a first / first electrode plate 11 disposed in a first region AR1 and a first / second electrode plate 12 disposed in a second region AR2 between the outer sheet 31 and the inner sheet 32 (see FIG. Figure 6 ).

[0084] The second electrode 20 includes a second / second electrode plate 22 disposed in the second region AR2 and corresponding to the first / first electrode plate 11 and the first / second electrode plate 12 and located inside the folded inner sheet 32 (see Figure 6 and Figure 7 ).

[0085] Reference Figure 7 The outermost unit cell 61 forms one unit cell in the second area AR2 by folding the outer sheet 31 and the inner sheet 32 facing each other, and also forms one unit cell between the first area AR1 and the second area AR2.

[0086] That is, in the second area AR2, the second / second electrode plate 22, the inner sheet 32, the first / second electrode plate 12, and the outer sheet 31 form a unit cell. The first / first electrode plate 11 and the inner sheet 32 of the first area AR1 and the second / second electrode plate 22 of the second area AR2 form a unit cell between the first area AR1 and the second area AR2.

[0087] Since the outermost unit cell 61 is disposed at one outermost side of the electrode assembly 6, the first / first electrode plate 11 of the first electrode 10 is disposed at the outermost side. Therefore, the first / first electrode plate 11 and the first / second electrode plate 12 forming the first electrode 10 (negative electrode) are respectively disposed at the outermost sides of the electrode assembly 6, thereby improving the safety of the electrode assembly 6.

[0088] Figure 8 is an electrode assembly (including an outermost unit cell and Figure 3 Cross-sectional view of the unit body). Figure 8 The electrode assembly 7 applied to the rechargeable battery according to the third exemplary embodiment further includes an outermost unit cell 71 provided at one outermost side of the electrode assembly 7. That is, the electrode assembly 7 is stacked Figure 3 The electrode assembly 7 is formed by stacking a plurality of unit cells (for example, two unit cells) and one outermost unit cell 71 of the outermost side of the electrode assembly 7 .

[0089] Figure 9 is applied to Figure 8 A cross-sectional view of the outermost unit body (including the electrode plate and separator) of the electrode assembly. Figure 9 The outermost unit cell 71 is formed by providing separators 40 at both surfaces of the first electrode 10. The separator 40 includes an outer sheet 41 and an inner sheet 42, and the first electrode 10 includes a first / third electrode plate 13 provided between the outer sheet 41 and the inner sheet 42.

[0090] Since the outermost unit cell 71 is disposed at one outermost side of the electrode assembly 7, the first / third electrode plate 13 of the first electrode 10 is disposed at the outermost side. Therefore, the first / first electrode plate 11 and the first / third electrode plate 13 forming the first electrode 10 (negative electrode) are disposed at both outermost sides of the electrode assembly 7, thereby improving the safety of the electrode assembly 7.

[0091] Figure 10 is a cross-sectional view of a state in which electrode plates and separators are stacked to form a unit body of an electrode assembly applied to a rechargeable battery according to a fourth exemplary embodiment of the present invention, Figure 11 By folding Figure 10 Cross-sectional view of a unit body formed by stacked separators. Figure 10 and Figure 11 The unit cell 81 includes three electrode plates of the first electrode 50 , three electrode plates of the second electrode 80 , and three separators 90 .

[0092] The partition plate 90 is provided as three sheets and includes a first area AR1 and a second area AR2 that are folded to face each other and divided relative to the folded center. As an example, the partition plate 90 includes an outer sheet 91 arranged on the outside in the folded state, an inner sheet 93 arranged on the inside in the folded state, and an intermediate sheet 92 arranged between the outer sheet 91 and the inner sheet 93.

[0093] The electrode plates forming the first electrode 50 and the electrode plates forming the second electrode 80 are alternately stacked while the outer sheet 91 , the intermediate sheet 92 , and the inner sheet 93 are placed in each of the first area AR1 and the second area AR2 .

[0094] The first electrode 50 includes a first / first electrode plate 11 disposed in a first area AR1 between the outer sheet 91 and the intermediate sheet 92, a first / second electrode plate 12 disposed in a second area AR2 between the outer sheet 91 and the intermediate sheet 92, and a first / fourth electrode plate 14 disposed between the folded inner sheets 93 (see FIG. Figure 10 ).

[0095] The second electrode 80 includes: a second / first electrode plate 21, corresponding to the first / first electrode plate 11, located outside the outer sheet 91 and arranged in the first area AR1; a second / fifth electrode plate 25, corresponding to the first / first electrode plate 11 and the first / fourth electrode plate 14, located between the middle sheet 92 and the inner sheet 93 and arranged in the first area AR1; a second / sixth electrode plate 26, corresponding to the first / second electrode plate 12 and the first / fourth electrode plate 14 and arranged in the second area AR2 (refer to FIG. Figure 10 ).

[0096] Since the first / first electrode plate 11, the first / second electrode plate 12 and the first / fourth electrode plate 14 and the second / first electrode plate 21, the second / fifth electrode plate 25 and the second / sixth electrode plate 26 are arranged on the outside and inside of the outer sheet 91, the middle sheet 92 and the inner sheet 93, and the outer sheet 91, the middle sheet 92 and the inner sheet 93 are folded relative to the folding center to manufacture the unit body 81, the separator 90 and the first electrode 50 and the second electrode 80 can be easily aligned in the manufacturing process of the unit body 81.

[0097] Reference Figure 11 The unit body 81 forms two unit cells in the first area AR1 and two unit cells in the second area AR2 by folding the outer sheet 91, the middle sheet 92 and the inner sheet 93 facing each other, and also forms one unit cell between the first area AR1 and the second area AR2.

[0098] That is, in the first area AR1, the second / first electrode plate 21, the outer sheet 91, the first / first electrode plate 11, the intermediate sheet 92, the second / fifth electrode plate 25, and the inner sheet 93 form two unit cells. In the second area AR2, the first / fourth electrode plate 14, the inner sheet 93, the second / sixth electrode plate 26, the intermediate sheet 92, the first / second electrode plate 12, and the outer sheet 91 form two unit cells. The second / fifth electrode plate 25, the inner sheet 93, and the first / fourth electrode plate 14 form one unit cell between the first area AR1 and the second area AR2.

[0099] Figure 12 By stacking Figure 11 A cross-sectional view of an electrode assembly formed by a unit body. Figure 12The electrode assembly 8 is formed by stacking and electrically connecting a plurality of unit cells 81. Although not shown, the unit cells are electrically connected to each other through lead tabs.

[0100] The stacking of the unit cells 81 to form the electrode assembly 8 facilitates the manufacturing process of the electrode assembly 8 and easily increases the capacity of the battery. That is, the unit cells 81 can improve the manufacturing efficiency and quality safety of the electrode assembly 8 and the rechargeable battery.

[0101] Figure 13 is an electrode assembly of a rechargeable battery according to a fifth exemplary embodiment of the present invention (including Figure 11 The unit body and Figure 7 A cross-sectional view of the outermost unit body).

[0102] Reference Figure 13 The electrode assembly 94 applied to the rechargeable battery according to the fifth exemplary embodiment further includes an outermost unit cell 61 disposed at one outermost side of the electrode assembly 94 .

[0103] That is, the electrode assembly 94 is stacked Figure 11 Multiple unit bodies 81 (for example, two unit bodies) and stacked on the outermost stacking side Figure 7 The outermost unit body 61 is formed.

[0104] Since the outermost unit cell 61 is disposed at the outermost side of the electrode assembly 94, the first / first electrode plate 11 of the first electrode 50 is disposed at the outermost side. Therefore, the first / first electrode plate 11 and the first / second electrode plate 12 forming the first electrode 50 (negative electrode) are respectively disposed at the outermost side of the electrode assembly 94, thereby improving the safety of the electrode assembly 94.

[0105] Figure 14 is an electrode assembly of a rechargeable battery according to a sixth exemplary embodiment of the present invention (including Figure 11 The unit body and Figure 9 The cross-sectional view of the outermost unit body). Figure 14 The electrode assembly 95 applied to the rechargeable battery according to the sixth exemplary embodiment further includes an outermost unit cell 71 disposed at one outermost side of the electrode assembly 95 .

[0106] That is, the electrode assembly 95 is stacked Figure 11 A plurality of unit bodies 81 (for example, two unit bodies) and stacked at one outermost stacking side Figure 9 The outermost unit body 71 is formed.

[0107] Since the outermost unit cell 71 is disposed at one outermost side of the electrode assembly 95, the first / third electrode plates 13 of the first electrode 50 are disposed at the outermost side. Therefore, the first / third electrode plates 13 and the first / second electrode plates 12 forming the first electrode 50 (negative electrode) are respectively disposed at the outermost sides of the electrode assembly 95, thereby improving the safety of the electrode assembly 95.

[0108] Figure 15 is a rechargeable battery according to a sixth exemplary embodiment of the present invention (by stacking Figure 3 The unit body and Figure 3 A cross-sectional view of an electrode assembly formed by a modification of a unit body. Figure 15 In the electrode assembly 2 ′ of a rechargeable battery according to the sixth exemplary embodiment of the present invention, the unit cell 1 ′ disposed at the lowermost side further includes an extension portion 31E in the outer sheet 31 .

[0109] Figure 16 is a rechargeable battery according to a seventh exemplary embodiment of the present invention (by stacking Figure 3 The unit body and Figure 3 A cross-sectional view of an electrode assembly formed by a modification of a unit body. Figure 16 In the electrode assembly 2 ″ of a rechargeable battery according to the seventh exemplary embodiment of the present invention, the unit cell 1 ′ disposed on the uppermost side further includes an extension portion 31E in the outer sheet 31 .

[0110] Figure 15 and Figure 16 The extension 31E of the outer sheet 31 covers the outside of the plurality of stacked unit cells 1 and 1' and is fixed by the finishing tapes T1 and T2. That is, the extension 31E of the outer sheet 31 allows the process of coating with an electrically insulating coating material to be omitted after forming the electrode assemblies 2' and 2". Figure 15 and Figure 16 In the embodiment, a difference occurs in the length of the extension portion 31E.

[0111] Figure 17 is a unit body (eg, Figure 10 A cross-sectional view of the stacked state of the unit body (with a change in the unit body), Figure 18 By folding Figure 17 The stacked partitions form a unit body ( Figure 11 A cross-sectional view of a modified unit body).

[0112] Reference Figure 17 and Figure 18 , unit body 81 'by Figure 10 and Figure 11The unit body 81 is formed by removing the second / first electrode plate 21. That is, the unit body 81' includes three electrode plates of the first electrode 50, two electrode plates of the second electrode 80', and three separators 90.

[0113] The second electrode 80′ includes: a second / fifth electrode plate 25, corresponding to the first / first electrode plate 11 and the first / fourth electrode plate 14, located between the middle sheet 92 and the inner sheet 93 and disposed in the first area AR1; a second / sixth electrode plate 26, corresponding to the first / second electrode plate 12 and the first / fourth electrode plate 14 and disposed in the second area AR2 (refer to FIG. Figure 17 and Figure 18 ).

[0114] Reference Figure 18 The unit body 81' forms one unit cell in the first area AR1 and two unit cells in the second area AR2 by folding the outer sheet 91, the middle sheet 92 and the inner sheet 93, and further forms one unit cell between the first area AR1 and the second area AR2.

[0115] That is, in the first area AR1, the outer sheet 91, the first / first electrode plate 11, the middle sheet 92, the second / fifth electrode plate 25, and the inner sheet 93 form one unit cell. In the second area AR2, the first / fourth electrode plate 14, the inner sheet 93, the second / sixth electrode plate 26, the middle sheet 92, the first / second electrode plate 12, and the outer sheet 91 form two unit cells.

[0116] The second / fifth electrode plate 25, the inner sheet 93 and the first / fourth electrode plate 14 form a unit cell between the first and second regions AR1 and AR2. The unit cell 81' does not arrange the second / first electrode plates of the second electrode at the outermost side, so that electrical insulation performance can be improved.

[0117] Figure 19 By stacking Figure 18 The electrode assembly formed by the unit body ( Figure 12 The deformed electrode assembly, i.e., Figure 11 The unit body and Figure 18 Cross-sectional view of the unit body). Figure 19 , the electrode assembly 8' is formed by stacking and electrically connecting a plurality of unit cells 81 and 81' to each other. Although not shown, the unit cells may be electrically connected to each other through lead tabs.

[0118] Stacking unit cells 81 and 81' to form electrode assembly 8' makes it easy to increase the capacity of the battery while facilitating the manufacturing process of electrode assembly 8'. In other words, unit cells 81 and 81' can improve the production efficiency and quality stability of electrode assembly 8' and rechargeable batteries. Electrode assembly 8' is provided with unit cell 81' on one of its outermost sides, eliminating the second / first electrode plate of the second electrode from being located at the outermost side, thereby improving electrical insulation performance.

[0119] Figure 20 is a unit body ( Figure 3 and Figure 7 The unit body and Figure 9 A sectional view of a state where the outermost unit body of the variant is separated, Figure 21 By stacking Figure 20 The electrode assembly formed by the unit body ( Figure 8 A cross-sectional view of a modified electrode assembly).

[0120] Reference Figure 20 and Figure 21 , the electrode assembly 2 ′ of a rechargeable battery according to the ninth exemplary embodiment of the present invention further includes an additional unit cell 72 additionally disposed at the outermost side where the unit cells 1 and the outermost unit cells 61 are stacked.

[0121] The additional unit body 72 is formed in a state where the inner sheet 42 is removed from the outermost unit body 71. The additional unit body 72 includes a separator as the outer sheet 41 provided outside the second electrode 20'.

[0122] The second electrode 20' includes a second / third electrode plate 23 disposed between the outer sheet 41 of the additional unit cell 72 and the outer sheet 31 of the outermost unit cell 61. Because the additional unit cell 72 is also disposed outside the outermost unit cell 61 on one side of the electrode assembly 2', the second / third electrode plate 23 of the second electrode 20' is disposed at the outermost side. This further improves the safety of the electrode assembly 2'.

[0123] The outermost unit cell 61 includes the same number of electrode plates and separators 30 of the first electrode 10, and includes one electrode plate of the second electrode 20' less than the number of electrode plates of the first electrode 10. The electrode plates of the first electrode 10 and the separators 30 are arranged in pairs in the outermost unit cell 61, and one electrode plate of the second electrode 20' is provided.

[0124] In the outermost unit body 61 , the partition 30 is provided in two sheets and is divided based on a folding center where the two sheets face each other and are folded, and includes an outer sheet 31 provided on the outside in a folded state and an inner sheet 32 provided on the inside in a folded state.

[0125] First electrode 10 includes first / first electrode plate 11 and first / second electrode plate 12 disposed between outer sheet 31 and inner sheet 32. Second electrode 20' includes second / second electrode plate 22 located inside folded inner sheet 32 and disposed correspondingly to first / first electrode plate 11 and first / second electrode plate 12. Thus, second / third electrode plate 23 of additional unit cell 72 and first / first electrode plate 11 of outermost unit cell 61 form a unit cell while being inserted into outer sheet 31.

[0126] Figure 22 is a unit body of an electrode assembly applied to a rechargeable battery according to a tenth exemplary embodiment of the present invention ( Figure 11 and Figure 18 The unit body and Figure 9 A cross-sectional view of a state where the outermost unit body of the change is separated, Figure 23 By stacking Figure 22 The electrode assembly formed by the unit body ( Figure 14 A cross-sectional view of a modified electrode assembly).

[0127] Reference Figure 22 and Figure 23 The electrode assembly 8 ″ of the rechargeable battery according to the tenth exemplary embodiment of the present invention includes a unit body 81 and an additional unit body 72, which is additionally provided on the outermost side of the unit body 81 ′ (with Figure 20 The outer side of the outermost unit body 61 corresponds to the outer side.

[0128] The additional unit body 72 is formed by removing the inner sheet 42 from the outermost unit body 71 (see Figure 9 The additional unit body 72 includes a separator as an outer sheet 41 provided outside the second electrode 80'.

[0129] The second electrode 80' includes a second / third electrode plate 23 disposed between the outer sheet 41 of the additional unit body 72 and the outer sheet 91 of the unit body 81'. Since the additional unit body 72 is also disposed outside the unit body 81' at one side of the electrode assembly 8", the second / third electrode plate 23 of the second electrode 80' is disposed at the outermost side. Therefore, the safety of the electrode assembly 8" can be improved.

[0130] The unit cell 81' includes the same number of electrode plates and separators 90 of the first electrode 50, and includes one less electrode plate of the second electrode 80' than the number of electrode plates of the first electrode 50. In the unit cell 81', three electrode plates and three separators 90 of the first electrode 50 are provided, and two electrode plates of the second electrode 80' are provided.

[0131] In the unit body 81', the partition 90 is set as three pieces and is divided based on the folding center where the three pieces face each other and are folded, and includes an outer piece 91 set on the outside in the folded state, an inner piece 93 set on the inside in the folded state, and an intermediate piece 92 set between the outer piece 91 and the inner piece 93.

[0132] The first electrode 50 includes a first / first electrode plate 11 and a first / second electrode plate 12 disposed between the outer sheet 91 and the middle sheet 92 , and a first / fourth electrode plate 14 disposed within the inner sheet 93 .

[0133] The second electrode 80 ′ includes: a second / fifth electrode plate 25 , which is located between the middle plate 92 and the inner plate 93 and is arranged corresponding to the first / first electrode plate 11 and the first / fourth electrode plate 14 ; and a second / sixth electrode plate 26 , which is arranged corresponding to the first / second electrode plate 12 and the first / fourth electrode plate 14 .

[0134] Therefore, the second / third electrode plate 23 of the additional unit body 72 and the first / first electrode plate 11 of the unit body 81 ′ form a unit cell while inserting the outer sheet 91 .

[0135] While the invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but on the contrary is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

[0136] <Description of symbols>

[0137] 1, 1', 81, 81': unit body

[0138] 2, 2', 2", 6, 7, 8, 8', 8", 94, 95: electrode assembly

[0139] 3: Shell

[0140] 4, 5: Lead lugs

[0141] 10, 50: First electrode (negative electrode) 11: First / first electrode plate

[0142] 12: First / Second Electrode Plate 13: First / Third Electrode Plate

[0143] 14: First / fourth electrode plate 20, 20', 80, 80': second electrode (positive electrode)

[0144] 21: Second / first electrode plate 22: Second / second electrode plate

[0145] 25: Second / fifth electrode plate 26: Second / sixth electrode plate

[0146] 30, 40, 90: partitions 31, 41, 91: outer sheets

[0147] 31E: Extension 32, 42, 93: Inner piece

[0148] 61, 71: Outermost unit body 72: Additional unit body

[0149] 92: Middle piece 301: First outer

[0150] 302: Second external AR1: First area

[0151] AR2: Second Area

[0152] S1: inner piece S3: outer piece

[0153] S2: Metal sheet

[0154] T1, T2: Termination zone

Claims

1. A rechargeable battery comprising a plurality of separate electrode unit cells, each electrode unit cell comprising: first partition; a first electrode plate and a second electrode plate of the first electrode disposed to be spaced apart from each other on one surface of the first separator; a second separator, disposed on the first electrode plate and the second electrode plate of the first electrode; as well as a first electrode plate of a second electrode corresponding to the first electrode plate of the first electrode and disposed on one surface of the second separator; The second electrode plate of the second electrode corresponds to the second electrode plate of the first electrode and is disposed on the other surface of the first separator. wherein the first separator and the second separator are folded apart from each other between the first electrode plate and the second electrode plate of the first electrode, and In each electrode unit body, a second separator is stacked between the second electrode plate of the first electrode and the first electrode plate of the second electrode.

2. The rechargeable battery according to claim 1, wherein: The plurality of individual electrode unit bodies are stacked in one direction.

3. The rechargeable battery according to claim 2, further comprising: The outermost unit body is provided at one side of the electrode unit body located at the outermost sides of the plurality of individual electrode unit bodies.

4. The rechargeable battery according to claim 3, wherein: The outermost unit body includes: third partition; A third electrode plate and a fourth electrode plate of the first electrode are disposed separately from each other on one surface of the third separator; a fourth separator disposed on the third electrode plate and the fourth electrode plate of the first electrode; and The third electrode plate of the second electrode corresponds to the third electrode plate of the first electrode and is disposed on one surface of the fourth separator. The third separator and the fourth separator are folded between the third electrode plate and the fourth electrode plate of the first electrode.

5. The rechargeable battery according to claim 3, wherein: The outermost unit cell includes two separators facing each other and an electrode plate of the first electrode interposed between the two separators.

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