CN203574050U - Strap-type battery cell and lithium ion battery - Google Patents

Abstract

The utility model provides a laminated electric core and a lithium ion battery. The laminated cell includes a first pole piece, a first tab foil, a first tab, a second pole piece, a second tab foil, a second tab, an isolation film, and a protective glue. The first tab has a first insulator, a first welding portion, and a first external connection portion. The first pole piece has: a first welding groove for accommodating the first welding part, the first welding part is welded with the first current collector; and a first receiving groove. The second tab has a second insulator, a second welding portion, and a second external connection portion. The second pole piece has: a second welding groove for accommodating the second welding part, the second welding part is welded to the second current collector, and the second welding part in the second welding part faces the first pole piece electrically connected to the first tab The second welding part is partly accommodated in the first receiving groove under the isolation and protection of the isolation film; in the second receiving groove, the first welding part of the first welding part facing the second pole piece electrically connected to the second tab is protected by the isolation film The isolation protection part is accommodated in the second receiving groove.

Description

Laminated cells and lithium-ion batteries

technical field

The utility model relates to the field of energy storage devices, in particular to a laminated electric core and a lithium ion battery.

Background technique

With the development of modern society, mobile devices are diversified and diverse. For example, the screen of the mobile phone is getting bigger and bigger, and the functions are getting more and more; the original portable notebook computer has developed into the current ultrabook; various PADs and e-books, etc. Correspondingly, the demand for secondary lithium-ion batteries is also increasing, requiring lithium-ion batteries to have a longer battery life and more stringent requirements for energy density.

Therefore, how to make full use of various means to increase the energy density of batteries and improve the performance of lithium-ion secondary batteries is very urgent. Among them, a new laminated cell structure design was born. By embedding the external tabs into one of the pole pieces of the battery cell, the other pole pieces are connected to the electricity through the tab foil to improve the internal space utilization of the battery. , to increase the energy density space of the laminated battery, and at the same time improve the safety and stability of the battery.

At present, the conventional processing technology of laminated lithium batteries is that the positive and negative plates and the separator are stacked alternately, and each layer of positive and negative plates is welded together by the tab foil, and then welded to the tab of the external device, thus causing the tab This part of the space between the glue and the main body of the battery cell is wasted, consuming the internal space of the battery, and reducing the capacity of the battery.

Utility model content

In view of the problems in the background technology, the purpose of this utility model is to provide a laminated battery cell and a lithium-ion battery, which can reduce the waste of the internal space of the battery cell caused by welding tabs.

Another object of the present utility model is to provide a laminated battery cell and a lithium ion battery, which can improve the reliability of tab welding.

Another object of the present invention is to provide a laminated battery cell and a lithium ion battery, which can increase the energy density of the battery cell.

Another object of the present utility model is to provide a laminated cell and a lithium-ion battery, which can improve the flexibility of tab design.

Another purpose of the utility model is to provide a laminated battery cell and a lithium-ion battery, which can ensure that the battery cell and the packaging bag are perfectly matched.

In order to achieve the above object, in the first aspect, the utility model provides a laminated battery cell, which includes: a plurality of first pole pieces, each first pole piece has a first current collector, formed on the first current collector The first diaphragm containing the first active material on the front and back; a plurality of first tab foils, electrically connected together and each first tab foil is electrically connected to the first current collector of a corresponding first pole piece; A pole tab is arranged and electrically connected to one of the plurality of first pole pieces; a plurality of second pole pieces, each second pole piece has a second current collector and is formed on the front and back surfaces of the second current collector A second diaphragm containing a second active material; a plurality of second tab foils, electrically connected together and each second tab foil is electrically connected to the second current collector of a corresponding second pole piece; the second tab , arranged and electrically connected on one of the plurality of second pole pieces; an isolation film, arranged between the plurality of first pole pieces and the plurality of second pole pieces; and a protective glue. Wherein, the first pole piece electrically connected to the first pole tab and the second pole piece electrically connected to the second pole tab are arranged adjacent to each other. The first tab has: a first insulator; two first welding parts, arranged on the first insulator and spaced apart from each other; and a first outer connection part, arranged on the first insulator and electrically connected to the two first welding parts . The first pole piece electrically connected to the first pole piece has: two first welding grooves, which are formed by exposing the first diaphragm of the first pole piece to the first current collector, respectively accommodating two of the first pole pieces. The first welding part, the two first welding parts are respectively welded to the first current collector in the two first welding grooves; the first receiving groove is arranged facing the second pole piece electrically connected to the second tab And it is spaced apart from the two first welding grooves. The second tab has: a second insulator; two second welding parts arranged on the second insulator and spaced apart from each other; and a second external connection part arranged on the second insulator and electrically connected to the two second welding parts . The second pole piece electrically connected to the second pole piece has: two second welding grooves, which are formed by exposing the second diaphragm of the second pole piece to the second current collector, respectively accommodating two of the second pole pieces. The second welding part, the two second welding parts are respectively welded to the second current collectors in the two second welding grooves, and the faces of the two second welding parts are electrically connected to the first tab The second welding part of the first pole piece is partly accommodated in the first receiving groove under the isolation and protection of the isolation film; and the second receiving groove is arranged facing the first pole piece electrically connected to the first pole piece and is connected to the two The two second welding slots are spaced apart, and the first welding part of the two first welding parts facing the second pole piece electrically connected to the second tab is partly accommodated in the second receiving slot under the isolation and protection of the isolation film. . The protective glue is respectively coated in the two first welding grooves and the two second welding grooves to cover the welding position of the first welding part of the corresponding first tab and the welding of the second welding part of the second tab parts.

In order to achieve the above object, in the second aspect, the utility model provides a lithium-ion battery, which includes: the laminated battery cell according to the first aspect of the utility model; electrolyte; and a packaging bag for packaging the laminate The laminated battery cell contains electrolyte solution so that the electrolyte solution soaks the plurality of first pole pieces and the plurality of second pole pieces of the laminated battery cell.

The beneficial effects of the utility model are as follows:

In the laminated electric core of the utility model, a first welding groove for welding the first lug and a first receiving groove for accommodating the second lug are arranged on the first pole piece, and correspondingly, the second pole piece is provided with a The second welding groove for welding the second lug and the second accommodation groove for the first lug of the accommodating part, and the protective glue is coated in the two first welding grooves and the two second welding grooves respectively, thereby , to reduce the waste of the internal space of the battery cell caused by welding the tabs, the reliability of the tab welding is higher, and the energy density of the battery cell is improved; at the same time, the flexibility of the tab design is improved, and it can be set anywhere around the cell Location.

When the first pole piece electrically connected to the first tab is arranged on the outermost layer, it can be close to the uncut surface of the packaging bag, so that the tab can be flush with the sealing edge of the packaging bag and close to the unpunched surface , so that the battery cell and the packaging bag are perfectly matched.

Description of drawings

Fig. 1 is an exploded perspective view of relevant components of a laminated cell according to the present invention;

Fig. 2 is a perspective view of some related components of Fig. 1 assembled together;

Fig. 3 is a perspective view of a laminated cell according to the present invention, but for the sake of clarity, the isolation film is omitted;

Fig. 4 is a perspective view of a laminated battery cell and a lithium-ion battery according to the present invention, wherein the packaging bag is shown with a dotted line, but for the sake of clarity, the separator is omitted;

Fig. 5 is a perspective view of an embodiment of the first pole piece and the first tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a first welding groove is shown by a dotted line;

Fig. 6 is a perspective view of an embodiment of the first pole piece and the first tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a first welding groove is shown by a dotted line;

Fig. 7 is a perspective view of an embodiment of the first pole piece and the first tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a first welding groove is shown by a dotted line;

Fig. 8 is a perspective view of an embodiment of the first pole piece and the first tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a first welding groove is shown by a dotted line;

Fig. 9 is a perspective view of an embodiment of the first pole piece and the first tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a first welding groove is shown by a dotted line;

Fig. 10 is a perspective view of an embodiment of the first pole piece and the first tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a second welding groove and a second receiving groove are shown by dotted lines ;

Fig. 11 is a perspective view of an embodiment of the second pole piece and the second tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a second welding groove and a second receiving groove are shown by dotted lines ;

Fig. 12 is a perspective view of an embodiment of the second pole piece and the second tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a second welding groove and a second receiving groove are shown by dotted lines ;

Fig. 13 is a perspective view of an embodiment of the second pole piece and the second tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a second welding groove and a second receiving groove are shown by dotted lines ;

Fig. 14 is a perspective view of an embodiment of the second pole piece and the second tab foil of the laminated battery cell according to the present invention, wherein for the sake of clarity, a second welding groove and a second receiving groove are shown by dotted lines ;

Wherein, the reference signs are explained as follows:

1 laminated cell 141 second current collector

11 The first pole piece 142 The second diaphragm

111 The first collector 143 The second welding groove

112 The first diaphragm 144 The second accommodation slot

113 The first welding slot 15 The second tab foil

114 The first receiving slot 16 The second tab

12 first tab foil 161 second insulator

13 The first tab 162 The second welding part

131 first insulator 163 second external part

132 The first welding part 17 Isolation film

133 The first external part 2 bags

14 Second pole piece 21 Unwashed surface

Detailed ways

The laminated cell and the lithium-ion battery according to the present invention will be described in detail below with reference to the accompanying drawings.

Firstly, the laminated battery cell according to the first aspect of the present invention will be described.

Referring to FIGS. 1 to 14 , the laminated battery cell 1 according to the present invention includes: a plurality of first pole pieces 11 , each first pole piece 11 has a first current collector 111 formed on the front and back sides of the first current collector 111 The first diaphragm 112 containing the first active material on the top; a plurality of first tab foils 12 are electrically connected together and each first tab foil 12 is electrically connected to the first current collector of a corresponding first pole piece 11 111; the first tab 13 is arranged and electrically connected to one of the plurality of first pole pieces 11; a plurality of second pole pieces 14, each second pole piece 14 has a second current collector 141, forming The second diaphragm 142 containing the second active material on the front and back of the second current collector 141; a plurality of second tab foils 15 are electrically connected together and each second tab foil 15 is electrically connected to a corresponding second The second current collector 141 of the pole piece 14; the second pole tab 16 is arranged and electrically connected to one of the plurality of second pole pieces 14; the isolation film 17 is arranged on the plurality of first pole pieces 11 and the plurality of second pole pieces 14; and a protective glue (not shown). Wherein, the first pole piece 11 electrically connected to the first pole tab 13 and the second pole piece 14 electrically connected to the second pole tab 16 are arranged adjacently. The first tab 13 has: a first insulator 131; two first soldering portions 132, disposed on the first insulator 131 and spaced apart from each other; and a first external connection portion 133, disposed on the first insulator 131 and electrically connected to the Two first welding parts 132 . The first pole piece 11 electrically connected to the first pole piece 13 has: two first welding grooves 113, which are formed by exposing the first diaphragm 112 of the first pole piece 11 to the first current collector 111, respectively accommodating the first Two first welding parts 132 of a tab 13, the two first welding parts 132 are respectively welded with the first current collectors 111 in the two first welding grooves 113; The second pole piece 14 to which the second tab 16 is electrically connected is disposed and spaced apart from the two first welding slots 113 . The second tab 16 has: a second insulator 161; two second soldering portions 162, disposed on the second insulator 161 and spaced apart from each other; and a second external connection portion 163, disposed on the second insulator 161 and electrically connected to the Two second welding parts 162 . The second pole piece 14 electrically connected to the second pole tab 16 has: two second welding grooves 143, which are formed by exposing the second diaphragm 142 of the second pole piece 14 to the second current collector 141, respectively accommodating the second The two second welding parts 162 of the dipole tab 16 are respectively welded to the second current collectors 141 in the two second welding grooves 143, and the two second welding parts The second welding part 162 facing the first pole piece 11 electrically connected to the first tab 13 in the part 162 is partly accommodated in the first receiving groove 114 under the isolation and protection of the isolation film 17; and the second receiving groove 144 faces The first pole piece 11 electrically connected to the first tab 13 is arranged and spaced apart from the two second welding grooves 143 , and the side of the two first welding parts 132 that is electrically connected to the second tab 16 faces The first welding portion 132 of the second pole piece 14 is partly accommodated in the second receiving groove 144 in an isolated and protected manner by the isolation film 17 . The protective glue is coated in the two first welding grooves 113 and the two second welding grooves 143 respectively, so as to cover the welding part of the first welding part 132 of the corresponding first tab 13 and the second welding part of the second tab 16. The welding position of the second welding part 162 .

In the laminated cell 1 of the present invention, the first pole piece 11 is provided with a first welding groove 113 for welding the first lug 13 and a first receiving groove 114 for accommodating the second lug 16, and correspondingly A second welding groove 143 for welding the second pole lug 16 and a second receiving groove 144 for accommodating the first pole lug 13 are provided on the second pole piece 14, and the protective glue is coated on the two first pole pieces respectively. Welding slot 113 and two second welding slots 143, thereby reducing the waste of the internal space of the battery cell caused by welding the tabs, the reliability of tab welding is higher, and the energy density of the battery cell is improved; The flexibility of the tab design can be set anywhere around the cell.

In an embodiment of the laminated battery cell 1 according to the present invention, the first pole piece 11 electrically connected to the first tab 13 is arranged on the outermost layer.

In an embodiment of the laminated battery cell 1 according to the present invention, the first pole piece 11 can be a negative pole piece, and the second pole piece 14 can be a positive pole piece. In another embodiment, the first pole piece 11 may be a positive pole piece, and the second pole piece 12 may be a negative pole piece. Correspondingly, appropriate first active material and second active material corresponding to the polarity of the pole piece can be selected.

In an embodiment of the laminated cell 1 according to the present invention, referring to FIG. 2 in conjunction with FIG. 1 , FIG. 3 and FIG. 4 , the first insulator 131 of the first tab 13 covers the two first welds. The slot 113 and the second receiving slot 144 ; the second insulator 161 of the second tab 16 covers the two second welding slots 143 and the first receiving slot 114 .

In an embodiment of the laminated cell 1 according to the present invention, referring to FIG. 3 and FIG. 4 , the first insulator 131 of the first tab 13 is flush with the inner and outer edges of the second insulator 161 of the second tab 16 .

In an embodiment of the stacked battery cell 1 according to the present invention, the thickness of the first welding portion 132 accommodated in the corresponding first welding groove 113 and the second receiving groove 144 is less than or equal to the thickness of the first welding portion at the corresponding position. The sum of the thicknesses of a diaphragm 112 and the second diaphragm 142; the thickness of the second welding portion 162 accommodated in the corresponding second welding groove 143 and the first receiving groove 114 is less than or equal to the second diaphragm at the corresponding position 142 and the thickness of the first diaphragm 112.

In an embodiment of the stacked battery cell 1 according to the present invention, referring to FIG. 1 and FIG. 2 , the area surrounded by the edge of the second receiving groove 144 covers the area of the first welding groove 113 opposite to the second receiving groove 144 The area enclosed by the edges: the area enclosed by the edges of the second welding groove 143 covers the area enclosed by the edges of the first receiving groove 114 opposite to the second welding groove 143 .

In an embodiment of the laminated battery cell 1 according to the present invention, referring to Fig. 5 to Fig. 14, each first welding groove 113 can be a groove with a closed bottom side (refer to the left and right sides in Fig. the left side, the left and right sides in Fig. 7, the left side in Fig. 8 and the right side in Fig. 9) or the through groove through up and down (refer to the right side in Fig. 6, the right side in Fig. 8 and the left side in Fig. 9); The second welding groove 143 can be a groove closed at the bottom (refer to the left and right sides in Fig. 10, the left and right sides in Fig. 11, the right side in Fig. 12, the right side in Fig. 13 and the left side in Fig. 14) or a through groove through up and down (refer to the left side in Fig. 12, the left side in Fig. 13 and the right side in Fig. 14); the first receiving groove 114 is a groove with a closed bottom side (refer to Fig. 5, Fig. 6 and Fig. 9 ) or a through groove through up and down (Refer to FIG. 7 and FIG. 8 ); the second accommodating groove 144 is a groove closed at the bottom (refer to FIG. 10 , FIG. 12 , and FIG. 14 ) or a through groove (refer to FIG. 11 and FIG. 13 ).

In an embodiment of the stacked battery cell 1 according to the present utility model, referring to FIG. 3 and FIG. 4 in conjunction with FIG. 1 and FIG. 2 , the plurality of first tab foils 12 are aligned with each other; The dipole tab foils 15 are aligned with each other.

In an embodiment of the laminated battery cell 1 according to the present invention, referring to Fig. 3 and Fig. 4, the plurality of first tab foils 12 are electrically connected by bending and welding; the plurality of second pole foils The ear foil 15 is electrically connected by bending and welding. In another embodiment, referring to FIG. 3 and FIG. 4 , the first tab foil 12 is bent by 45-90 degrees. The second tab foil 15 is bent at 45-90 degrees. It should be noted that in Fig. 3 and Fig. 4, the outermost first tab foil 12 and the adjacent second tab foil 15 are not bent, because their dimensions are relatively short (refer to Fig. 1 and Fig. 2) , without bending, the bending of the first tab foil 12 and the second tab foil 15 can be changed according to different production needs, as long as the size of the laminated battery 1 is not exceeded, multiple first poles The tab foil 12 and the plurality of second tab foils 15 may be electrically connected together by bending and welding.

In an embodiment of the laminated cell 1 according to the present invention, referring to FIG. 1 , the isolation film 17 may be in the form of a single piece. In another embodiment, the separator 17 is a whole piece folded between the first pole piece 11 and the second pole piece 14 .

In an embodiment of the laminated cell 1 according to the present invention, the protective glue can be green glue.

The cell according to the present invention can be a cell of a battery or a cell of a capacitor. The battery may be, but not limited to, a lithium-ion battery, and the capacitor may be, but not limited to, a lithium-ion supercapacitor.

The lithium ion battery according to the second aspect of the present invention will be described below.

The lithium-ion battery according to the second aspect of the utility model includes: the laminated battery cell 1 according to the first aspect of the utility model; the electrolyte (not shown); and a packaging bag 2 for packaging the laminated battery cell 1 And contain the electrolyte so that the electrolyte can infiltrate the multiple first pole pieces 11 and the multiple second pole pieces 14 of the laminated battery cell 1 .

In an embodiment of the lithium-ion battery according to the present invention, referring to FIG. 4 , the first pole piece 11 electrically connected to the first tab 13 is arranged on the outermost layer and is close to the unwashed pit surface 21 of the packaging bag 2 . Thus, the tabs can be flush with the sealing edge of the packaging bag and close to the surface 21 without punching the hole, so that the battery cell and the packaging bag are perfectly matched.

Claims (10)

1. A laminated cell (1), comprising: A plurality of first pole pieces (11), each first pole piece (11) has a first current collector (111), and a first diaphragm containing a first active material formed on the front and back surfaces of the first current collector (111) (112); A plurality of first tab foils (12) are electrically connected together and each first tab foil (12) is electrically connected to the first current collector (111) of a corresponding first pole piece (11); The first tab (13), arranged and electrically connected to one of the plurality of first pole pieces (11); A plurality of second pole pieces (14), each second pole piece (14) has a second current collector (141), and a second diaphragm containing a second active material formed on the front and back surfaces of the second current collector (141) (142); A plurality of second tab foils (15), electrically connected together and each second tab foil (15) is electrically connected to the second current collector (141) of a corresponding second pole piece (14); The second tab (16), arranged and electrically connected to one of the plurality of second pole pieces (14); and An isolation film (17), arranged between the plurality of first pole pieces (11) and the plurality of second pole pieces (14); It is characterized in that, The first pole piece (11) electrically connected to the first pole piece (13) and the second pole piece (14) electrically connected to the second pole piece (16) are arranged adjacent to each other; The first tab (13) has: first insulator (131); Two first welding parts (132), arranged on the first insulator (131) and spaced apart from each other; and The first external connection part (133) is arranged on the first insulator (131) and electrically connected to the two first welding parts (132); The first pole piece (11) electrically connected with the first pole ear (13) has: The two first welding grooves (113) are formed by exposing the first diaphragm (112) of the first pole piece (11) to the first current collector (111), respectively accommodating two ends of the first pole piece (13). a first welding part (132), the two first welding parts (132) are respectively welded to the first current collector (111) in the two first welding grooves (113); The first receiving groove (114) is arranged facing the second pole piece (14) electrically connected to the second pole lug (16) and spaced apart from the two first welding grooves (113); The second tab (16) has: second insulator (161); Two second welding parts (162), arranged on the second insulator (161) and spaced apart from each other; and The second external connection part (163) is arranged on the second insulator (161) and electrically connected to the two second welding parts (162); The second pole piece (14) electrically connected with the second pole lug (16) has: The two second welding grooves (143) are formed by exposing the second diaphragm (142) of the second pole piece (14) to the second current collector (141), respectively accommodating the two pole pieces of the second pole piece (16). two second welding parts (162), the two second welding parts (162) are respectively welded to the second current collectors (141) in the two second welding grooves (143), and the two second welding parts (162) are welded to the second current collectors (141) in the two second welding grooves (143), and the two second welding parts In the second welding part (162), the second welding part (162) facing the first pole piece (11) electrically connected to the first tab (13) is partly housed in the first accommodating part under the isolation protection of the isolation film (17). slot (114); and The second receiving groove (144) is arranged facing the first pole piece (11) electrically connected to the first pole lug (13) and is spaced apart from the two second welding grooves (143), the two first Among the welding parts (132), the first welding part (132) facing the second pole piece (14) electrically connected to the second pole lug (16) is partly accommodated in the second accommodation groove under isolation and protection of the isolation film (17) within (144); The laminated cell (1) also includes: The protective glue is coated in the two first welding grooves (113) and the two second welding grooves (143) respectively, so as to cover the welding parts and The welding position of the second welding part (162) of the second tab (16). the 2. The laminated battery cell (1) according to claim 1, characterized in that the first pole piece (11) electrically connected to the first tab (13) is arranged on the outermost layer. the 3. The laminated battery cell (1) according to claim 1, characterized in that the first pole piece (11) is a negative pole piece, and the second pole piece (14) is a positive pole piece. the 4. The stacked cell (1) according to claim 1, characterized in that, The first insulator (131) of the first tab (13) covers the two first welding grooves (113) and the second receiving groove (144); The second insulator (161) of the second tab (16) covers the two second welding grooves (143) and the first receiving groove (114). the 5. The laminated cell (1) according to claim 1, characterized in that, The first insulator (131) of the first tab (13) is flush with the inner and outer edges of the first insulator (161) of the first tab (16). the 6. The laminated cell (1) according to claim 1, characterized in that, The thickness of the first welding part (132) accommodated in the corresponding first welding groove (113) and second accommodation groove (144) is less than or equal to the thickness of the first diaphragm (112) and the second diaphragm ( 142) the sum of the thickness; The thickness of the second welding part (162) contained in the corresponding second welding groove (143) and the first receiving groove (114) is less than or equal to the thickness of the second diaphragm (142) and the first diaphragm ( 112) the sum of the thicknesses. the 7. The laminated cell (1) according to claim 3, characterized in that, The area surrounded by the edge of the second accommodation groove (144) covers the area surrounded by the edge of the first welding groove (113) opposite to the second accommodation groove (144); The area enclosed by the edge of the second welding groove (143) covers the area enclosed by the edge of the first accommodation groove (114) opposite to the second welding groove (143). the 8. The laminated cell (1) according to claim 1, characterized in that, Each first welding groove (113) is a groove closed on the bottom side or a through groove through up and down; Each second welding groove (143) is a groove closed on the bottom side or a through groove through up and down; The first receiving groove (114) is a groove closed on the bottom side or a through groove through up and down; The second accommodating groove (144) is a groove with a closed bottom side or a through groove that penetrates up and down. the 9. A lithium ion battery, characterized in that, comprising: The laminated cell (1) according to any one of claims 1-8; electrolyte; and A packaging bag (2), encapsulating the laminated battery cell (1) and containing electrolyte so that the electrolyte can infiltrate multiple first pole pieces (11) and multiple second pole pieces ( 14). the 10. The lithium ion battery according to claim 9, characterized in that; The first pole piece (11) electrically connected to the first pole lug (13) is arranged on the outermost layer and is close to the unwashed pit surface (21) of the packaging bag (2). the

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