Energy storage device and power utilization system

Abstract

The invention discloses an energy storage device and a power utilization system. The energy storage device comprises a battery cell, a shell, a top cover assembly, an adapter and an insulating film, wherein the battery cell comprises a main body and a tab arranged on the end surface of the main body; the shell is provided with a cavity with an opening in one end, and the cavity is used for accommodating a battery cell; the top cover assembly seals the opening of the shell, and the top cover assembly is provided with a pole; the adapter is arranged between the top cover assembly and the battery cell, one end of the adapter is welded with the tab, the other end of the adapter is connected with the pole, and a welding printing area is arranged on the surface of one side, deviating from the tab, of the adapter in the thickness direction of the adapter; and the insulating film comprises a transparent part and a non-transparent part which are integrally formed, the non-transparent part covers the welding printing area, and at least part of the transparent part is attached to the main body.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of battery, in particular to a kind of energy storage device and power system. BACKGROUND

[0002] In the related art, the cell in the secondary battery is generally formed by winding process or laminating process, then the tab in the cell is connected with the pole of the top cover assembly, and then the insulating film is attached on both sides of the tab. However, the tab on the cell is very thin, generally micron level, relatively soft, and is prone to folding, which causes the folded tab to fail to connect the cell and the pole of the top cover assembly, resulting in increased internal resistance of the cell.

[0003] Then, in order to detect the above-mentioned cell with tab folding, manual visual inspection can be used, but manual visual inspection is low in efficiency, and the staff is prone to fatigue and missed detection after long time work, resulting in poor detection accuracy of tab folding. SUMMARY

[0004] The present application discloses a kind of energy storage device and power system. The energy storage device not only can facilitate identification whether tab is folded, effectively improve the detection efficiency and accuracy of tab folding, but also can facilitate identification whether the welding mark of tab is attached with insulating film.

[0005] To achieve the above purpose, in a first aspect, the present application discloses an energy storage device, comprising:

[0006] a cell, the cell comprising a main body and a tab provided on an end face of the main body;

[0007] a housing, the housing having a chamber with an open end, the chamber being used to accommodate the cell;

[0008] a top cover assembly, the top cover assembly closing the opening of the housing, the top cover assembly having a pole;

[0009] an adapter, the adapter being provided between the top cover assembly and the cell, one end of the adapter being welded with the tab, the other end of the adapter being connected with the pole, the adapter having a welding mark area on the surface of the side of the adapter away from the tab along the thickness direction of the adapter; and

[0010] an insulating film, the insulating film comprising a transparent part and an opaque part formed integrally, and the opaque part covering the welding mark area, at least part of the transparent part being attached to the main body.

[0011] In the embodiment, the opaque part of the insulating film is used to cover the welding mark area, which can effectively avoid the welding slag generated by the welding of the adapter and the tab from falling into the main body of the battery cell, prevent the short circuit between the positive plate and the negative plate in the main body caused by the falling of the welding slag into the main body, thereby avoiding the low capacity of the battery cell caused by the short circuit in the main body, and also preventing the burr generated by the welding of the tab and the adapter from scratching the top cover assembly to cause the separation between the tab and the adapter, thereby avoiding the poor conduction between the tab and the top cover assembly. In addition, the opaque part of the insulating film covers the welding mark area, which can make it easier to take pictures and identify the opaque part when taking pictures of the welding mark position of the tab and the adapter by the camera, thereby facilitating the judgment of whether the welding mark area is attached with the insulating film.

[0012] By attaching at least part of the transparent part to the main body, the tab can still be observed through the transparent part when it is folded to the main body, so that when the camera takes pictures of the area near the main body and the area near the tab, the tab can be judged by analyzing the pictures. Compared with attaching the opaque insulating film to the area near the tab and manually inspecting, the identification of whether the tab is folded is greatly facilitated, and the detection efficiency and accuracy of whether the tab is folded are effectively improved. At the same time, when the tab is folded to the main body, the folded tab can also prevent the short circuit between the tab and the shell of the energy storage device, thereby improving the safety of the energy storage device.

[0013] The transparent part and the opaque part of the insulating film are integrally formed, and only one attachment operation is needed to attach the opaque part to the welding mark area and at least part of the transparent part to the main body. This not only facilitates the camera to take pictures of the welding mark area, the area near the main body, and the area near the tab, thereby facilitating the detection and judgment of whether the welding mark area is attached with the insulating film and whether the tab is folded to the main body, and improving the detection accuracy, but also simplifies the process of attaching the insulating film and reduces the cost.

[0014] In a possible implementation manner of the first aspect, the end face of the main body is rectangular, the end face of the main body has a width direction, the adapter has a pole connecting part and two tab welding parts, the tab welding parts are located on both sides of the pole connecting part in the width direction, the welding mark area is located in the middle region of the tab welding part, and the opaque part covers the tab welding part.

[0015] Thus, the edge portion of the tab welding portion can also be covered by the opaque portion, preventing the burr on the edge of the tab welding portion from being rubbed off by the lower plastic in the top cover assembly and falling into the main body of the battery cell, avoiding short circuit in the main body due to the burr falling into the main body, and further avoiding low capacity of the battery cell due to the short circuit in the main body.

[0016] In a possible implementation manner of the first aspect, the insulating film is rectangular, the transparent portion and the opaque portion are arranged along a direction in which the main body points to the tab, and an area of the transparent portion is equal to an area of the opaque portion.

[0017] Thus, the length of the transparent portion and the length of the opaque portion can be substantially the same, and the width of the transparent portion and the width of the opaque portion can be substantially the same, facilitating the manufacturing of the insulating film.

[0018] In a possible implementation manner of the first aspect, the insulating film is L-shaped, and an included angle between a plane in which the transparent portion is located and a plane in which the opaque portion is located towards the side of the battery cell is 90°-120°.

[0019] Thus, after the tab is bent, the insulating film is less likely to affect the distance between the adapter and the main body of the battery cell, that is, the distance between the adapter and the main body of the battery cell can still be small, while effectively preventing the welding slag from falling onto the main body and preventing the burr on the adapter from being rubbed by the lower plastic on the top cover assembly, without adversely affecting the volume of the secondary battery, thereby facilitating the improvement of the energy ratio of the secondary battery.

[0020] In a possible implementation manner of the first aspect, the tab has a tab bending region, a boundary line between the transparent portion and the opaque portion is located in the tab bending region, and the tab bending region is a region of the tab close to the main body and used for forming a bend towards the adapter.

[0021] Thus, when the insulating film is attached, the position to which the boundary line between the transparent portion and the opaque portion is attached can be identified relatively quickly through the tab bending region, so that the transparent portion and the opaque portion can be attached to the corresponding positions relatively quickly, greatly improving the attachment efficiency of the insulating film.

[0022] In a possible implementation manner of the first aspect, the insulating film comprises a transparent substrate, the transparent substrate has a first region and a second region arranged along a width direction of the insulating film, the first region is coated with an opaque adhesive layer to form the opaque portion, and the second region is coated with a transparent adhesive layer to form the transparent portion.

[0023] Thus, the opaque portion and the transparent portion can be manufactured by the same substrate, reducing the manufacturing cost of the insulating film.

[0024] In a possible implementation manner of the first aspect, the transparent portion has a light transmittance greater than or equal to 30%.

[0025] Therefore, when the tab is detected by the camera, the transparent portion can be used to clearly detect whether the tab is folded onto the main body, and the transparency requirement of the transparent portion is reduced, and the cost is reduced.

[0026] In a possible implementation manner of the first aspect, the transparent portion has a color different from the color of the tab corresponding to the area where the transparent portion is attached.

[0027] Therefore, the influence of the transparent portion on the judgment of the folded tab can be effectively reduced, the folded tab can be easily judged, and the accuracy of the judgment of whether the tab is folded is improved.

[0028] In a possible implementation manner of the first aspect, the tab includes positive and negative tabs arranged at intervals, and the color of the transparent portion is different from the color of the positive tab and the color of the negative tab.

[0029] Therefore, when the insulating film is attached, the insulating film with the transparent portion of other colors does not need to be selected according to the colors of the positive and negative tabs, and the insulating film can be attached to the corresponding position, which greatly facilitates the attachment of the insulating film and improves the production efficiency of the energy storage device.

[0030] In a possible implementation manner of the first aspect, the color of the opaque portion is at least one of blue, green, gray, and black.

[0031] Therefore, the opaque portion can be easily photographed and identified, and the area of the opaque portion can be easily judged from the photo, so that whether the opaque portion completely covers the welding mark area of the tab can be easily identified and judged, and the efficiency and accuracy of the camera photographing detection and identification of whether the welding mark area is attached with the insulating film are further improved.

[0032] In a possible implementation manner of the first aspect, the end surface of the main body is rectangular, the end surface of the main body has a length direction, the tab includes positive and negative tabs arranged at intervals along the length direction, the insulating film includes a first insulating film corresponding to the positive tab and a second insulating film corresponding to the negative tab, the size of the first insulating film along the length direction is greater than or equal to the size of the positive tab along the length direction, and the size of the second insulating film along the length direction is greater than or equal to the size of the negative tab along the length direction.

[0033] Therefore, the first insulating film can cover the welding pad area of the corresponding adapter while covering the positive tab in the length direction when adhering, so as to prevent the area close to the main body from short-circuiting between the positive tab and the top cover assembly or between the positive and negative tabs in the main body, and the second insulating film can cover the welding pad area of the corresponding adapter while covering the negative tab in the length direction when adhering, so as to prevent the area close to the main body from short-circuiting between the negative tab and the top cover assembly or between the positive and negative tabs in the main body, thereby effectively improving the safety of the battery cell.

[0034] In a possible implementation of the first aspect, the first insulating film and the second insulating film are spaced apart in the length direction.

[0035] Therefore, the use amount of the insulating film can be reduced, and the cost is reduced.

[0036] In a possible implementation of the first aspect, in the direction of the main body pointing to the tab, the size of the transparent part is greater than or equal to the size of the tab.

[0037] Therefore, when the tab is completely folded onto the main body, the transparent part can still cover the folded tab, so as to prevent the folded tab from short-circuiting with the shell of the secondary battery due to the part not being covered by the insulating film, thereby improving the safety of the secondary battery of the battery cell after assembly.

[0038] In a second aspect, the application further discloses a power utilization system comprising the energy storage device in the first aspect.

[0039] In the embodiment, the energy storage device of the power utilization system is the energy storage device in the first aspect, and therefore the energy storage device in the embodiment has the technical effects of the energy storage device in the first aspect.

[0040] Compared with the prior art, the application has the following beneficial effects:

[0041] In the application, the opaque part of the insulating film is used to cover the welding pad area, which can effectively prevent the welding slag generated by the welding of the adapter and the tab from falling into the main body of the battery cell, prevent the positive tab and the negative tab in the main body from short-circuiting due to the falling of the welding slag into the main body, thereby avoiding the low capacity of the battery cell due to the short-circuiting in the main body, and preventing the burrs generated by the welding of the tab and the adapter from scratching the top cover assembly, thereby preventing the tab and the adapter from being separated, and avoiding the poor conduction between the tab and the top cover assembly.

[0042] By at least part of the transparent part being attached to the main body, when the tab is folded to the main body, the tab can still be observed through the transparent part, so that when the camera takes a photo of the area where the tab is close to the main body and the area where the main body is close to the tab, the tab can be judged by analyzing the photo, compared with the way of attaching the opaque insulating film to the main body close to the tab area and manually inspecting, which greatly facilitates the identification of whether the tab is folded, and effectively improves the detection efficiency and accuracy of whether the tab is folded. At the same time, when the tab is folded to the main body, the folded tab can also prevent short circuit with the shell of the energy storage device, improving the use safety of the energy storage device.

[0043] The transparent part and the opaque part of the insulating film are integrally formed, and only one attachment operation is needed to attach the opaque part to the welding mark area, and at least part of the transparent part is attached to the main body. Not only is it convenient for the camera to take a photo of the welding mark area, the area where the tab is close to the main body, and the area where the main body is close to the tab, thereby facilitating the detection and judgment of whether the welding mark area is attached with the insulating film and whether the tab is folded to the main body, improving the detection accuracy, but also simplifying the process of attaching the insulating film and reducing the cost. BRIEF DESCRIPTION OF DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0045] Figure 1 is a structural schematic diagram of a battery cell when a tab is folded to a main body provided by an embodiment of the present application;

[0046] Figure 2 is a perspective view of an energy storage device provided by an embodiment of the present application;

[0047] Figure 3 is a perspective view of an adapter provided by an embodiment of the present application;

[0048] Figure 4 is a perspective view of an insulating film provided by an embodiment of the present application;

[0049] Figure 5 is a structural schematic diagram of a battery cell, an insulating film and an adapter when a tab has not been bent provided by an embodiment of the present application;

[0050] Figure 6 is a structural schematic diagram of a battery cell provided by an embodiment of the present application;

[0051] Figure 7 is a structural schematic diagram of an insulating film provided by an embodiment of the present application;

[0052] Figure 8 is a structural schematic diagram of an electricity utilization system provided by an embodiment of the present application.

[0053] Legend of reference signs:

[0054] 1 - insulating film; 1a - first insulating film; 1b - second insulating film; 11 - opaque part; 12 - transparent part; 11a - transparent substrate; 11b - opaque adhesive layer; 11c - transparent adhesive layer; 2 - battery cell; 21 - main body; 22 - tab; 221 - negative tab; 222 - positive tab; 3 - adapter; 3a - positive adapter; 3b - negative adapter; 31 - pole connecting part; 32 - tab welding part; 4 - top cover assembly; 41 - pole; 5 - shell;

[0055] 100 - electricity utilization system; 10 - energy storage device; 20 - electric energy conversion device; 30 - electricity utilization load. DETAILED DESCRIPTION

[0056] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0057] In the present application, the terms “mount”, “set”, “provided with”, “connect”, “connected” should be understood broadly. For example, it can be fixed connection, detachable connection, or integral configuration; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication between two devices, elements or components. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0058] In addition, the terms “first”, “second” and the like are mainly used to distinguish different devices, elements or components (the specific types and configurations may be the same or different), and are not intended to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, the meaning of “multiple” is two or more.

[0059] Rechargeable battery, also known as secondary battery or storage battery, refers to a battery that can be activated by charging after discharging to continue to be used. The recyclable characteristics of the secondary battery make it gradually become the main power source of the electrical equipment. With the increasing demand for secondary batteries, people have higher requirements for their energy density, reliability and cost. The tab as the main connection site plays a crucial role in the energy efficiency of the battery cell.

[0060] In the related art, the battery cell in the secondary battery is generally formed by a winding process or a laminating process, then a plurality of tabs of the same polarity in the battery cell are welded to form a tab group, the tab group is welded and connected with a pole post in a top cover assembly through an adapter, and then an insulating film is attached on the side of the tab group and the adapter welded with each other and the other side opposite to the side, so as to block the tab group and the adapter from other structures. However, the thickness of the tab on the battery cell is very thin, generally in microns, and is relatively soft, and is prone to folding. For example, in the process of welding a plurality of tabs to form a tab group, the tab is folded to the main body of the battery cell, so that the folded tab cannot play a role of connecting the battery cell and the pole post, causing the internal resistance of the battery cell to increase, thereby causing the battery cell to generate more heat during use, which adversely affects the service life and safety of the secondary battery. Figure 1 As shown in a structure diagram of a battery cell when a tab is folded to the main body, the dashed box a is the folded tab part.

[0061] Then, in order to detect the above-mentioned battery cell with tab folding, manual visual inspection can be used, but manual visual inspection is low in efficiency, and the staff is prone to fatigue and missed detection after long time work, resulting in poor detection accuracy of tab folding.

[0062] Therefore, the application discloses a kind of energy storage device and power system. The energy storage device not only can conveniently identify whether tab is folded, effectively improves the detection efficiency and accuracy of tab folding, but also can conveniently identify whether the welding mark of tab is attached with insulating film.

[0063] The technical solutions of the application will be further described below with reference to specific embodiments and drawings.

[0064] The embodiment provides an energy storage device, as shown in Figure 2 And Figure 3As shown, the energy storage device 10 includes the electric core 2, the shell 5, the top cover assembly 4, the adapter 3 and the insulation film 1. The electric core 2 includes the main body 21 and the tab 22 arranged on the end face of the main body 21; the shell 5 has a chamber with an open end, the chamber being used for accommodating the electric core 2; the top cover assembly 4 closes the opening of the shell 5, and the top cover assembly 4 has the pole 41; the adapter 3 is arranged between the top cover assembly 4 and the electric core 2, one end of the adapter 3 is welded with the tab 22, the other end is connected with the pole 41, and the adapter 3 has a welding mark area on the side surface thereof away from the tab 22 along the thickness direction thereof; and the insulation film 1 includes the transparent part 12 and the opaque part 11 which are integrally formed, and the opaque part 11 covers the welding mark area, and at least part of the transparent part 12 is attached to the main body 21.

[0065] It should be noted that the welding mark area refers to the area on the side surface of the adapter 3 away from the tab 22 for welding, such as the area on the side surface of the adapter 3 away from the tab 22 for welding with the tab 22. Figure 2 The area shown in the dashed box b in the middle.

[0066] It should be further noted that the opaque part 11 covering the welding mark area can be that the opaque part 11 exactly covers the welding mark area, i.e. the size of the opaque part 11 is basically consistent with the size of the welding mark area; or the opaque part 11 can have a coverage area greater than the area of the welding mark area, i.e. the size of the opaque part 11 is greater than the size of the welding mark area, which is not limited herein.

[0067] In the above, the opaque part 11 of the insulation film 1 is used to cover the welding mark area, which can effectively avoid the welding slag generated by the welding of the adapter 3 and the tab 22 from falling into the main body 21 of the electric core 2, prevent the short circuit between the positive plate and the negative plate in the main body 21 caused by the welding slag falling into the main body 21, thereby avoiding the low capacity of the electric core 2 caused by the short circuit in the main body 21, and also preventing the burrs generated by the welding of the tab 22 and the adapter 3 from scratching the top cover assembly 4 to cause the separation between the tab 22 and the adapter 3, thereby avoiding the poor conduction between the tab 22 and the top cover assembly 4; and the opaque part 11 of the insulation film 1 covering the welding mark area can also make it easier to take a photo and identify the opaque part 11 when taking a photo of the welding position of the tab 22 and the adapter 3 by using a camera, thereby facilitating the judgment of whether the welding mark area is attached with the insulation film 1.

[0068] By attaching the at least part of the transparent part 12 to the main body 21, when the tab 22 is folded to the main body 21, the tab 22 can still be observed through the transparent part 12, so that when the area of the tab 22 close to the main body 21 and the area of the main body 21 close to the tab 22 are photographed by the camera, whether the tab 22 is folded to the main body 21 can be determined by analyzing the photographed photo. Compared with the way of attaching the non-transparent insulating film 1 to the area of the main body 21 close to the tab 22 and manually checking, the identification of whether the tab 22 is folded is greatly facilitated, and the detection efficiency and accuracy of whether the tab 22 is folded are effectively improved. At the same time, when the tab 22 is folded to the main body 21, the folded tab 22 can also prevent short circuit with the shell 5 of the energy storage device 10, and the use safety of the energy storage device 10 is improved.

[0069] In the related art, the transparent part 12 and the non-transparent part 11 can be two separate insulating films 1. However, when the two separate insulating films 1 are attached, the edges close to each other will have overlapping parts. If the overlapping area is small, it is easy to cause part of the welding mark area of the tab 22 not to be attached. If the overlapping area is large, the non-transparent insulating film 1 is easy to be attached to the main body 21, which causes the tab 22 to be unable to be detected even if it is folded to the main body 21 when photographed by the camera. Moreover, the two insulating films 1 need to be attached twice, which increases the process of attaching the insulating film 1, reduces the efficiency, and increases the cost.

[0070] Therefore, in the present application, the transparent part 12 and the non-transparent part 11 are integrally formed, so that the non-transparent part 11 can be attached to the welding mark area only once, and the at least part of the transparent part 12 is attached to the main body 21. This not only facilitates the camera to photograph the welding mark area, the area of the tab 22 close to the main body 21, and the area of the main body 21 close to the tab 22, thereby facilitating the detection and determination of whether the welding mark area is attached with the insulating film 1 and whether the tab 22 is folded to the main body 21, and improving the detection accuracy, but also simplifies the process of attaching the insulating film 1, thereby reducing the cost.

[0071] The at least part of the transparent part 12 attached to the main body 21 can be that the transparent part 12 is only attached to the main body 21, or that part of the transparent part 12 is attached to the area of the tab 22 close to the main body 21 and the other part is attached to the main body 21, which is not limited herein.

[0072] In addition, as Figure 4As shown, the insulation film 1 can be wound into a roll, and the transparent part 12 and the opaque part 11 both extend along the winding direction of the insulation film 1, that is, the transparent part 12 and the opaque part 11 both extend along the winding direction of the insulation film 1, so that the insulation film 1 can be cut according to the size of the welding area along the winding direction of the insulation film 1 when the insulation film 1 is attached, that is, the insulation film 1 can be adapted to the tab 22 of different sizes. Of course, the insulation film 1 can also be in a laminated form, at this time, the size of the insulation film 1 can be customized according to the size of the welding area, so that the insulation film 1 does not need to be cut when attached, effectively simplifying the process of attaching the insulation film 1 and improving the efficiency.

[0073] The energy storage device 10 can include any one of a secondary battery, a battery pack, a battery module, a battery cluster, etc., which is not limited herein. The following will be described in detail taking the energy storage device 10 including a secondary battery as an example.

[0074] The tab 22 of the energy storage device 10, that is, the tab 22 of the secondary battery can include a positive tab 222 and a negative tab 221, the adapter 3 includes a positive adapter 3a and a negative adapter 3b, and the pole 41 in the top cover assembly 4 includes a positive pole and a negative pole. The positive tab 222 is electrically connected to the positive pole through the positive adapter 3a, and the negative tab 221 is electrically connected to the negative pole through the negative adapter 3b.

[0075] When connecting the tab 22, the adapter 3 and the pole 41, the positive adapter 3a is welded to the positive pole, and the negative adapter 3b is welded to the negative pole. Then, the adapter 3 is placed side by side with the cell 2, and the end face of the tab 22 of the cell 2 is arranged to face the adapter 3. Then, the positive adapter 3a is welded to the positive tab 222 of the cell 2, and the negative adapter 3b is welded to the negative tab 221. Then, the insulation film 1 is adhered at the position where the positive adapter 3a is welded to the positive tab 222 and the position where the main body 21 of the cell 2 is close to the positive tab 222, and the insulation film 1 is adhered at the position where the negative adapter 3b is welded to the negative tab 221 and the position where the main body 21 of the cell 2 is close to the negative tab 221. Finally, the positive tab 222 and the negative tab 221 are bent, so that the top cover assembly 4, the adapter 3 and the cell 2 are stacked. At this time, the bent positive tab 222 and the negative tab 221 can be located between the adapter 3 and the main body 21 of the cell 2, and the insulation film 1 can be bent together with the positive tab 222 and the negative tab 221.

[0076] In addition, the number of cells 2 can be one, two or more, which is not limited herein. For example, when the number of cells 2 is two, the number of positive tabs 222 and the number of negative tabs 221 are both two. At this time, the positive adapter 3a is welded to the two tabs 22 respectively, and the negative adapter 3b is welded to the two negative tabs 221 respectively.

[0077] Optionally, as shown in FIG. 6, the insulation film 1 can be a laminated film, and the transparent part 12 and the opaque part 11 can be arranged on the insulation film 1 in a laminated manner. Figure 2 andFigure 3 As shown, the end face of the main body 21 is rectangular, the end face of the main body 21 has a width direction (as shown by the direction of x), the adapter 3 has a pole connecting portion 31 and two tab welding portions 32, the tab welding portions 32 are located on both sides of the pole connecting portion 31 in the width direction, the welding mark area is located in the middle region of the tab welding portion 32, and the opaque portion 11 covers the tab welding portion 32. Figure 2

[0078] Thus, the edge portion of the tab welding portion 32 can also be covered by the opaque portion 11, preventing the burrs on the edge of the tab welding portion 32 from being scratched off and falling into the main body 21 of the battery cell 2 in the top cover assembly 4, avoiding short circuit in the main body 21 due to the burrs falling into the main body 21, and further avoiding low capacity of the battery cell 2 due to short circuit in the main body 21.

[0079] Among them, the opaque portion 11 covering the tab welding portion 32 can be that the opaque portion 11 just covers the tab welding portion 32, that is, the size of the opaque portion 11 is basically the same as the size of the tab welding portion 32; or the covering area of the opaque portion 11 is larger than the tab welding portion 32, that is, the size of the opaque portion is larger than the size of the tab welding portion 32, which is not limited here.

[0080] In addition, after the tab 22 in the battery cell 2 is welded with the adapter 3, and before the tab 22 is bent, as shown, Figure 5 The insulating film 1 is rectangular, the transparent portion 12 and the opaque portion 11 are arranged along the direction of the main body 21 pointing to the tab 22, and the area of the transparent portion 12 is equal to the area of the opaque portion 11.

[0081] Thus, the length of the transparent portion 12 and the length of the opaque portion 11 can be approximately the same, the width of the transparent portion 12 and the width of the opaque portion 11 can be approximately the same, facilitating the manufacture of the insulating film 1.

[0082] And when the insulating film 1 is cut, only the size of the insulating film 1 perpendicular to the arrangement direction of the transparent portion 12 and the opaque portion 11 needs to correspond to the size of the tab welding portion 32 of the adapter 3 and the tab 22, facilitating the cutting of the insulating film 1.

[0083] It needs to be explained that the above-mentioned insulating film 1 is rectangular, which means that the shape of the insulating film 1 is approximately rectangular, and it does not mean that the shape of the insulating film 1 must be rectangular.

[0084] In other embodiments, after the tab 22 in the battery cell 2 is welded with the adapter 3, and the tab 22 is bent, as shown, Figure 2 The shape of the insulating film 1 is L-shaped, and the included angle between the plane where the transparent portion 12 is located and the plane where the opaque portion 11 is located towards the side of the battery cell 2 is 90°-120°.​

[0085] Thus, after the tab 22 is bent, the insulating film 1 cannot easily affect the distance between the adapter 3 and the main body 21 of the battery cell 2, i.e., the distance between the adapter 3 and the main body 21 of the battery cell 2 can still be small, which effectively prevents the welding slag from falling onto the main body 21 and prevents the burr on the adapter 3 from rubbing against the lower plastic on the top cover assembly 4, while not adversely affecting the volume of the secondary battery, which is conducive to improving the energy ratio of the secondary battery.

[0086] It should be explained that the shape of the insulating film 1 is L-shaped, which means that after the tab 22 is bent, the opaque part 11 covering the tab welding part 32 will move together and bend relative to the transparent part 12, so that the opaque part 11 and the opaque part 11 have an included angle, and the cross section of the insulating film 1 along its own thickness direction is roughly L-shaped.

[0087] Among them, the included angle between the plane where the transparent part 12 is located and the plane where the opaque part 11 is located towards the side of the battery cell 2 can be 90°, 100°, 113°, 120°, etc., which is not limited here.

[0088] Further, as shown in Figure 2 , Figure 5 and Figure 6 , the tab 22 has a tab bending area (as shown by the dashed line box c in Figure 6 ), the boundary line between the transparent part 12 and the opaque part 11 is located in the tab bending area, and the tab bending area is the area of the tab 22 close to the main body 21 and used to form a bend towards the adapter 3.

[0089] Thus, when attaching the insulating film 1, the boundary line between the transparent part 12 and the opaque part 11 can be quickly identified by the tab bending area, so that the transparent part 12 and the opaque part 11 can be quickly attached to the corresponding positions, greatly improving the attachment efficiency of the insulating film 1.

[0090] Among them, the boundary line between the transparent part 12 and the opaque part 11 is located in the tab bending area, which should be understood that part of the transparent part 12 can be attached in the tab bending area, and part of the opaque part 11 can also be attached in the tab bending area.

[0091] The insulating film 1 can have various implementations. In one possible implementation, the insulating film 1 can include transparent substrates and opaque substrates arranged side by side along the width direction of the insulating film 1, and a layer of adhesive is coated on the same side of the transparent substrates and the opaque substrates to facilitate the pasting of the insulating film 1. The transparent substrates and the layer of adhesive coated thereon can form the transparent portion 12 of the insulating film 1, and the opaque substrates and the layer of adhesive coated thereon can form the opaque portion 11 of the insulating film 1. In this way, the same layer of adhesive can be coated on the transparent substrates and the opaque substrates, so that the layer of adhesive can be directly coated without distinguishing the boundary between the transparent substrates and the opaque substrates when the insulating film 1 is manufactured, thereby reducing the difficulty of manufacturing the insulating film 1.

[0092] In another possible implementation, as shown in FIG. 1B, the insulating film 1 includes a transparent substrate 11a having a first region (as shown by the dashed box d1 in FIG. 1B) and a second region (as shown by the dashed box d2 in FIG. 1B) arranged side by side. The first region is coated with an opaque layer 11b to form the opaque portion 11, and the second region is coated with a transparent layer 11c to form the transparent portion 12. Figure 7 Figure 7 Figure 7

[0093] In this way, the opaque portion 11 and the transparent portion 12 can be manufactured from the same substrate, thereby reducing the manufacturing cost of the insulating film 1.

[0094] The transparent substrate 11a can be made of PET (polyethylene terephthalate), so that the insulating film 1 has good insulation and heat resistance, and the cost of the insulating film 1 is low, thereby reducing the cost of the secondary battery. Of course, the transparent substrate 11a can also be made of PBT (polybutylene terephthalate), PE (polyethylene), or the like, which is not limited herein.

[0095] In addition, the opaque layer 11b can be an acrylic adhesive layer, so that the insulating film 1 can be firmly adhered to the adapter 3 or the tab 22 and the main body 21. Of course, the opaque layer 11b can also be an organic silicon pressure-sensitive adhesive, which is not limited herein. The implementation of the transparent layer 11c can be substantially the same as that of the opaque layer 11b, which is not described herein again, as long as the transparent layer 11c can transmit light, and the opaque layer 11b cannot transmit light.

[0096] Optionally, the light transmittance of the transparent portion 12 is greater than or equal to 30%.

[0097] ​​​Therefore, when the camera takes a photo of the tab 22, it can clearly detect whether the tab 22 is folded on the main body 21 through the transparent part 12, while reducing the transparency requirement of the transparent part 12 and reducing the cost.

[0098] It should be explained that the light transmittance refers to the ability of light to pass through a medium, which is the percentage of the light flux passing through the transparent body or the translucent body to the incident light flux, that is, the percentage between the light flux passing through the transparent part 12 and the light flux irradiated to the transparent part 12 is the light transmittance of the transparent part 12.

[0099] The light transmittance of the transparent part 12 can be detected by a visible light transmittance instrument, an ultraviolet light transmittance instrument, a haze light transmittance comprehensive instrument, etc. For example, when the light transmittance of the transparent part 12 is detected by a light transmittance instrument, an infrared 850nm light source, an infrared 940nm light source and a visible 550nm light source can be used to irradiate the transparent part 12 of the insulating film 1 to be detected, respectively. The light transmittance instrument sensor detects the incident light intensity and the transmitted light intensity after passing through the transparent part 12 of the three light sources, respectively. The percentage ratio between the transmitted light intensity and the incident light intensity is the transmittance of the transparent part 12.

[0100] To distinguish the transparent part 12 from the tab 22, the color of the transparent part 12 can be other colors than the color of the tab 22 corresponding to the area where the transparent part 12 is attached. That is, the color of the transparent part 12 is different from the color of the tab 22 welded to the adapter 3 covered by the corresponding opaque part 11.

[0101] Therefore, when the camera takes a photo of the tab 22, it can clearly detect whether the tab 22 is folded on the main body 21 through the transparent part 12, while reducing the transparency requirement of the transparent part 12 and reducing the cost.

[0102] For example, the tab 22 in the battery cell 2 generally includes a positive tab 222 and a negative tab 221. The material of the positive tab 222 is generally aluminum or aluminum alloy, and the material of the negative tab 221 is generally nickel, copper or copper alloy. That is, the color of the positive tab 222 is generally silver-white of aluminum or aluminum alloy, the color of the negative tab 221 is generally silver-white of nickel or copper-nickel-plated silver, or purple-red or red-brown of copper or copper alloy.

[0103] Therefore, in order to distinguish the color of the transparent part 12 from the color of the tab 22, the transparent part 12 corresponding to the positive tab 222 can be other colors than silver-white of aluminum foil, and the transparent part 12 corresponding to the negative tab 221 can be other colors than silver-white of nickel foil or purple-red or red-brown of copper foil.

[0104] Further, as shown in Figures 2-6 The color of the transparent part 12 is different from the color of the positive tab 222 and the color of the negative tab 221.

[0105] Therefore, when attaching the insulating film 1, the insulating film 1 with the transparent part 12 of other colors does not need to be selected according to the colors of the positive tab 222 and the negative tab 221, and the insulating film 1 can be attached to the corresponding position, which greatly facilitates the attachment of the insulating film 1 and improves the production efficiency of the energy storage device 10.

[0106] The color of the transparent part 12 can be any one of gray, green, black, purple, etc.

[0107] Of course, the transparent part 12 can also be colorless, which is not limited herein.

[0108] In addition, the color of the opaque part 11 can be at least one of blue, green, gray, black, etc.

[0109] Therefore, the opaque part 11 can be easily identified and photographed, and the area of the opaque part 11 can be easily determined from the photo, so that whether the opaque part 11 completely covers the solder pad area of the adapter 3 and whether the opaque part 11 completely covers the solder pad area of the tab 22 for welding with the adapter 3 can be easily identified and determined, and the efficiency and accuracy of detecting and identifying whether the insulating film 1 is attached to the solder pad area by camera shooting are further improved.

[0110] Of course, the opaque part 11 can also be opaque white, which is not limited herein.

[0111] Alternatively, the color of the opaque part 11 and the color of the transparent part 12 can be two different colors, so that the opaque part 11 and the transparent part 12 can be more easily identified when detected by the camera, and the detection efficiency is improved.

[0112] Alternatively, as shown in Figure 2 and Figure 5 The end surface of the main body 21 is rectangular, and the end surface of the main body 21 has a length direction (e.g., the direction indicated by y in Figure 5 The tab 22 includes the positive tab 222 and the negative tab 221 arranged at intervals along the length direction, the insulating film 1 includes the first insulating film 1a corresponding to the positive tab 222 and the second insulating film 1b corresponding to the negative tab 221, the size of the first insulating film 1a along the length direction is greater than or equal to the size of the positive tab 222 along the length direction, and the size of the second insulating film 1b along the length direction is greater than or equal to the size of the negative tab 221 along the length direction.

[0113] Thus, the first insulating film 1a can cover the welding area of the corresponding adapter 3 and the positive tab 222 in the length direction when adhered, so as to prevent short circuit between the area close to the main body 21 of the positive tab 222 and the top cover assembly 4 or the positive and negative tabs in the main body 21, and the second insulating film 1b can cover the welding area of the corresponding adapter 3 and the negative tab 221 in the length direction when adhered, so as to prevent short circuit between the area close to the main body 21 of the negative tab 221 and the top cover assembly 4 or the positive and negative tabs in the main body 21, effectively improving the safety of the battery cell 2.

[0114] Preferably, the size of the first insulating film 1a in the length direction is greater than the size of the positive tab 222 in the length direction, and the size of the second insulating film 1b in the length direction is greater than the size of the negative tab 221 in the length direction, so that when the insulating film 1 is attached, the edge of the first insulating film 1a in the length direction can be flush with the edge of the positive tab 222 without special attention, and the edge of the second insulating film 1b in the length direction can be flush with the edge of the negative tab 221 without special attention.

[0115] In addition, the size of the opaque part 11 of the insulating film 1 in the width direction of the end surface of the main body 21 can be greater than or equal to the size of the area of the tab 22 for welding with the adapter 3 in the width direction, so that when the insulating film 1 is attached, the opaque part 11 can completely cover the area of the tab 22 for welding with the adapter 3.

[0116] The size of the opaque part 11 in the width direction can also be less than or equal to the size of the tab 22 in the width direction, so that the opaque part 11 can cover the area of the tab 22 for welding with the adapter 3 while reducing the size of the opaque part 11, thereby reducing the cost.

[0117] Optionally, the first insulating film 1a and the second insulating film 1b have a gap in the length direction.

[0118] Thus, the amount of the insulating film 1 used can be reduced, the cost is reduced, and compared with the way of connecting the insulating film 1 attached to the positive tab 222 and the insulating film 1 attached to the negative tab 221, the insulating film 1 can prevent interference with other structures in the secondary battery, such as interference with the lower plastic in the top cover assembly 4.

[0119] In the direction of the main body 21 pointing to the tab 22, the size of the transparent part 12 is greater than or equal to the size of the tab 22.

[0120] Therefore, when the tab 22 is completely folded onto the main body 21, the transparent part 12 can still cover the folded tab 22, so as to prevent the folded tab 22 from being short-circuited with the shell 5 of the secondary battery due to the fact that the tab 22 is not covered by the insulating film 1, and the safety of the secondary battery assembled with the battery cell 2 is improved.

[0121] It should be explained that the direction along the main body 21 to the tab 22 can be along the height direction of the battery cell 2, for example, when the battery cell 2 is a square battery cell 2, the direction along the main body 21 to the tab 22 can be parallel to the height direction of the battery cell 2, such as the direction shown in Figure 2 and Figure 5 z in FIG. 4.

[0122] The embodiment also provides a power utilization system 100, as shown in Figure 8 FIG. 5, comprising the energy storage device 10 described in the above embodiment.

[0123] In the embodiment, the energy storage device 10 of the power utilization system 100 is the energy storage device 10 described in the above embodiment, and thus the energy storage device 10 in the embodiment has the technical effects of the energy storage device 10 in the above embodiment. Since the technical effects of the energy storage device 10 have been fully described in the above embodiment, they will not be described here again.

[0124] In addition, the power utilization system 100 can further comprise an electric energy conversion device 20 and a power utilization load 30. The electric energy conversion device 20 is used to convert other forms of energy into electric energy, and the energy storage device 10 can store at least part of the electric energy converted by the electric energy conversion device 20. The energy storage device 10 is also used to provide electric energy to the power utilization load 30, for example, the power utilization load 30 is a household appliance and a street lamp. When the power grid is powered off or blacked out, the energy storage device 10 can supply power to the household appliance and the street lamp.

[0125] In addition, the electric energy conversion device 20 can convert at least one of solar energy, light energy, wind energy, heat energy, tidal energy, biomass energy and mechanical energy into electric energy. The electric energy conversion device 20 can be a solar panel, a windmill, a geothermal power generation device, etc.

[0126] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit it. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or make equivalent replacements to some or all of the technical features. Such modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An energy storage device, characterized in that: The application relates to a battery cell, a shell, a top cover assembly, an adapter, and an insulation film. The battery cell comprises a main body and a tab arranged on an end surface of the main body. The shell has a chamber with an open end, and the chamber is used for accommodating the battery cell. The top cover assembly is used for closing the opening of the shell, and the top cover assembly has a pole. The adapter is arranged between the top cover assembly and the battery cell, one end of the adapter is welded with the tab, the other end of the adapter is connected with the pole, and the adapter has a welding mark area on a side surface of the adapter which is away from the tab in the thickness direction of the adapter. The insulation film comprises a transparent part and an opaque part which are integrally formed, and the opaque part covers the welding mark area, and at least part of the transparent part is attached to the main body. The end surface of the main body is rectangular, the end surface of the main body has a width direction, the adapter has a pole connecting part and two tab welding parts, the tab welding parts are located on both sides of the pole connecting part in the width direction, the welding mark area is located in the middle region of the tab welding parts, and the opaque part covers the tab welding parts.

2. The energy storage device of claim 1, wherein, The insulation film is rectangular, the transparent part and the opaque part are arranged along the direction of the main body to the tab, and the area of the transparent part is equal to the area of the opaque part.

3. The energy storage device of claim 2, wherein, The insulation film is L-shaped, and the included angle between the plane where the transparent part is located and the plane where the opaque part is located towards the side of the battery cell is 90-120 degrees.

4. The energy storage device of claim 2, wherein, The tab has a tab bending area, the boundary line between the transparent part and the opaque part is located in the tab bending area, and the tab bending area is the region of the tab close to the main body and used for forming a bending towards the adapter.

5. The energy storage device of claim 4, wherein, The insulation film comprises a transparent substrate, the transparent substrate has a first region and a second region arranged side by side, the first region is coated with an opaque adhesive layer to form the opaque part, and the second region is coated with a transparent adhesive layer to form the transparent part.

6. The energy storage device of any one of claims 1-5, wherein, The light transmittance of the transparent part is greater than or equal to 30%.

7. The energy storage device of any one of claims 1-5, wherein, The color of the transparent part is other than the color of the tab in the region where the transparent part is attached.

8. The energy storage device of any one of claims 1-5, wherein, The tab comprises positive tabs and negative tabs arranged at intervals, the color of the transparent part is different from the colors of the positive tabs and the negative tabs.

9. The energy storage device of claim 8, wherein, The color of the opaque part is at least one of blue, green, gray and black.

10. The energy storage device of claim 8, wherein, The end surface of the main body is rectangular, the end surface of the main body has a length direction, the tab comprises positive tabs and negative tabs arranged at intervals along the length direction, the insulation film comprises a first insulation film corresponding to the positive tabs and a second insulation film corresponding to the negative tabs, the size of the first insulation film along the length direction is greater than or equal to the size of the positive tabs along the length direction, and the size of the second insulation film along the length direction is greater than or equal to the size of the negative tabs along the length direction.

11. The energy storage device of any one of claims 1-5, wherein, The first insulation film and the second insulation film have intervals along the length direction.

12. The energy storage device of claim 11, wherein, In the direction of the main body to the tab, the size of the transparent part is greater than or equal to the size of the tab.

13. The energy storage device of any one of claims 1-5, wherein, ​ 14. A power utilization system characterized by The energy storage device of claim 1. The energy storage device of claim 1.

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