Energy storage device and electric system

Abstract

Provided in the embodiments of the present disclosure are an energy storage device and an electric system. The energy storage device (10) comprises a battery cell (2), a casing (5), a top cover assembly (4), adapters (3) and insulating films (1), wherein the battery cell (2) comprises a main body (21) and tabs (22) arranged on an end face of the main body (21); the casing (5) is provided with a cavity having an opening at one end, the cavity being configured to accommodate the battery cell (2); the top cover assembly (4) seals the opening of the casing (5), and the top cover assembly (4) is provided with terminal posts; the adapters (3) are arranged between the top cover assembly (4) and the battery cell (2), each adapter (3) has one end welded to a tab (22) and the other end connected to a terminal post, and each adapter (3) is provided with a weld mark area on the side surface facing away from the tab (22) in the direction of thickness; and each insulating film (1) comprises an integrally formed transparent portion (12) and non-transparent portion (11), the non-transparent portion (11) covering a weld mark area, and the transparent portion (12) being at least partially attached to the main body (21).

Description

An energy storage device and power system

[0001] Related cross-references

[0002] This disclosure claims priority to Chinese Patent Application No. 2024104942848, filed on April 23, 2024, entitled “An Energy Storage Device and Electricity System”, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to energy storage devices and power systems. Background Technology

[0004] In related technologies, the cells in rechargeable batteries are generally manufactured using winding or stacking processes. Then, the tabs in the cell are connected to the terminals in the top cover assembly, and insulating films are attached to both sides of the tabs. However, the tabs on the cell are very thin, typically at the micrometer level, and quite flexible, making them prone to folding. Folded tabs fail to function as a connection between the cell and the terminals in the top cover assembly, resulting in increased internal resistance within the cell.

[0005] In order to detect the cells with the aforementioned tab flipping, manual visual inspection can be performed. However, manual visual inspection is inefficient, and workers are prone to fatigue and missed detections after working for a long time, resulting in poor accuracy in detecting tab flipping. Summary of the Invention

[0006] (a) Technical problems to be solved

[0007] Visually inspecting the tabs on the battery cell for folding is inefficient, and workers are prone to fatigue and missing certain areas after long hours of work, resulting in poor accuracy in detecting folded tabs.

[0008] (II) Technical Solution

[0009] According to various embodiments disclosed in this application, an energy storage device and an electrical system are provided.

[0010] An energy storage device, comprising:

[0011] A battery cell, the battery cell comprising a body and tabs disposed on the end face of the body;

[0012] A housing having a cavity open at one end for accommodating the battery cell;

[0013] A top cover assembly that closes the opening of the housing, the top cover assembly having a pole post;

[0014] An adapter, disposed between the top cover assembly and the battery cell, wherein one end of the adapter is welded to the tab and the other end is connected to the terminal post, and the adapter has a solder area on its surface opposite to the tab along its thickness direction; and

[0015] An insulating film comprising an integrally formed transparent portion and an opaque portion, wherein the opaque portion covers the soldering area and at least a portion of the transparent portion is attached to the body.

[0016] Therefore, by using the opaque portion of the insulating film to cover the soldering area, it is possible to effectively prevent solder slag generated during the welding of the adapter and the tab from falling into the main body of the cell. This prevents short circuits between the positive and negative electrodes in the main body caused by solder slag falling into the main body, thus avoiding low cell capacity due to short circuits within the main body. At the same time, it also prevents burrs generated during the welding of the tab and the adapter from rubbing against the top cover assembly, thus preventing separation between the tab and the adapter and avoiding poor conductivity between the tab and the top cover assembly. Furthermore, the opaque portion of the insulating film covering the soldering area makes it easier to photograph and identify the opaque portion when taking pictures of the soldering position of the tab and the adapter with a camera, thereby facilitating the determination of whether the soldering area is covered with insulating film.

[0017] By attaching at least a portion of the transparent part to the main body, the tabs can still be observed even if they fold over onto the main body. This allows for analysis of photographs taken of the areas near the tabs and the main body, as well as the areas near the tabs, to determine if the tabs have folded over. Compared to attaching an opaque insulating film to the area near the tabs and relying on manual visual inspection, this method significantly simplifies the identification of folded tabs, effectively improving the efficiency and accuracy of tab fold detection. Furthermore, it prevents short circuits between the folded tabs and the energy storage device's casing, enhancing the safety of the energy storage device.

[0018] Furthermore, the transparent and opaque parts of the insulating film are integrally formed, requiring only one application operation to attach the opaque part to the solder area and at least part of the transparent part to the main body. This not only facilitates the camera's ability to photograph the solder area, the area of ​​the tab near the main body, and the area of ​​the main body near the tab, but also facilitates the detection and judgment of whether the solder area is covered with insulating film and whether the tab is folded onto the main body, improving the detection accuracy. It also simplifies the process of applying the insulating film and reduces costs.

[0019] An electrical system includes the energy storage device described above.

[0020] Therefore, the energy storage device in the power system is the energy storage device described above. This energy storage device effectively prevents short circuits between the positive and negative electrodes caused by welding slag falling into the main body, thus avoiding low cell capacity due to short circuits within the main body. Simultaneously, it prevents burrs generated during welding of the tabs and adapters from rubbing against the top cover assembly, thus preventing poor conductivity between the tabs and the top cover assembly. Furthermore, the opaque portion of the insulating film covering the solder area allows for easy photographing and identification of the opaque portion when photographing the solder area of ​​the tabs and adapters, facilitating the determination of whether the solder area is covered by the insulating film. Additionally, photographing can detect whether the tabs have folded onto the main body, effectively improving the detection efficiency and accuracy of tab folding.

[0021] Other features and advantages of this disclosure will be set forth in the following description and will be apparent in part from the description or may be learned by practicing the disclosure. The objects and other advantages of this disclosure are realized and obtained through the structures particularly pointed out in the description, claims, and drawings, details of one or more embodiments of this disclosure being set forth in the following drawings and description.

[0022] To make the above-described objects, features and advantages of this disclosure more apparent and understandable, optional embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0023] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure.

[0024] To more clearly illustrate the technical solutions in the embodiments of this disclosure or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 is a schematic diagram of the structure of a battery cell when the tab is folded onto the main body according to an embodiment of this application;

[0026] Figure 2 is a perspective view of an energy storage device provided in an embodiment of this application;

[0027] Figure 3 is a perspective view of an adapter provided in an embodiment of this application;

[0028] Figure 4 is a perspective view of an insulating film provided in an embodiment of this application;

[0029] Figure 5 is a schematic diagram of the structure of the battery cell, insulating film and adapter assembly when the tab is not bent, according to an embodiment of this application.

[0030] Figure 6 is a schematic diagram of the structure of a battery cell provided in an embodiment of this application;

[0031] Figure 7 is a schematic diagram of the structure of an insulating film provided in an embodiment of this application;

[0032] Figure 8 is a schematic diagram of the structure of an electrical system provided in an embodiment of this application. Detailed Implementation

[0033] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the solutions disclosed herein will be further described below. It should be noted that, unless otherwise specified, the embodiments and features described herein can be combined with each other.

[0034] Numerous specific details are set forth in the following description in order to provide a full understanding of this disclosure, but this disclosure may also be implemented in other ways different from those described herein; obviously, the embodiments in the specification are only some, and not all, of the embodiments of this disclosure.

[0035] The terms "first" and "second," etc., in this disclosure and its claims are used to distinguish different objects, not to describe a specific order of objects. For example, "first camera" and "second camera" are used to distinguish different cameras, not to describe a specific order of cameras.

[0036] In this disclosure, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this disclosure should not be construed as preferred or advantageous over other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner. Furthermore, in the description of the embodiments in this disclosure, unless otherwise stated, "a plurality of" means two or more.

[0037] A rechargeable battery, also known as a secondary battery or accumulator, is a battery that can be recharged after discharge to reactivate its active materials and continue to be used. The recyclable nature of rechargeable batteries has made them a primary power source for electrical devices. As the demand for rechargeable batteries increases, higher requirements are placed on their energy density, reliability, and cost. The tabs, as the main connection points, play a crucial role in the energy efficiency of the battery cell.

[0038] In related technologies, the cells in a rechargeable battery are generally manufactured using winding or stacking processes. Multiple tabs of the same polarity within the cell are then welded together to form a tab group. This tab group is then connected to the terminals in the top cover assembly via an adapter. Insulating films are then attached to the side of the tab group welded to the adapter and the opposite side to isolate the tab group and adapter from other structures. However, the tabs on the cell are very thin, typically at the micrometer level, and quite flexible, making them prone to folding. If, during the welding process, a tab folds onto the cell body, it fails to connect the cell to the terminals, increasing the cell's internal resistance. This leads to increased heat generation during use, negatively impacting the battery's lifespan and safety. Figure 1 shows a schematic diagram of a cell structure with a tab folded onto the body; the dashed box a represents the folded tab portion.

[0039] In order to detect the cells with the aforementioned tab flipping, manual visual inspection can be performed. However, manual visual inspection is inefficient, and workers are prone to fatigue and missed detections after working for a long time, resulting in poor accuracy in detecting tab flipping.

[0040] Based on this, this application discloses an energy storage device and a power supply system. The energy storage device can not only easily identify whether the electrode tabs are folded, effectively improving the detection efficiency and accuracy of electrode tab folding, but also easily identify whether an insulating film is attached to the solder joint of the electrode tabs.

[0041] The technical solution of this application will be further described below with reference to specific embodiments and accompanying drawings.

[0042] This embodiment provides an energy storage device, as shown in Figures 2 and 3. The energy storage device 10 includes a battery cell 2, a housing 5, a top cover assembly 4, an adapter 3, and an insulating film 1. The battery cell 2 includes a main body 21 and tabs 22 disposed on the end face of the main body 21. The housing 5 has a cavity with one open end for accommodating the battery cell 2. The top cover assembly 4 closes the opening of the housing 5 and has a terminal post 41. The adapter 3 is disposed between the top cover assembly 4 and the battery cell 2. One end of the adapter 3 is welded to the tab 22, and the other end is connected to the terminal post 41. The adapter 3 has a soldering area on its surface opposite to the tab 22 along its thickness direction. The insulating film 1 includes an integrally formed transparent portion 12 and an opaque portion 11, with the opaque portion 11 covering the soldering area, and at least a portion of the transparent portion 12 attached to the main body 21.

[0043] It should be noted that the aforementioned soldering area refers to the area on the surface of the adapter 3 facing away from the tab 22 that is used for welding, such as the area of ​​the adapter 3 used for welding with the tab 22, as shown in the dashed box b in Figure 2.

[0044] It should also be noted that the opaque portion 11 covering the solder area can mean that the opaque portion 11 exactly covers the solder area, that is, the size of the opaque portion 11 is basically the same as the size of the solder area; or it can mean that the coverage area of ​​the opaque portion 11 is larger than the area of ​​the solder area, that is, the size of the opaque portion 11 is larger than the size of the solder area. No limitation is made here.

[0045] In the above-mentioned case, by using the opaque portion 11 of the insulating film 1 to cover the soldering area, the solder slag generated from the welding of the adapter 3 and the tab 22 can be effectively prevented from falling into the body 21 of the cell 2. This prevents short circuits between the positive and negative electrodes in the body 21 caused by the solder slag falling into the body 21, thereby avoiding a low capacity of the cell 2 due to short circuits in the body 21. At the same time, it can also prevent the burrs generated from the welding of the tab 22 and the adapter 3 from rubbing against the top cover assembly 4, thus preventing the tab 22 and the adapter 3 from separating, thereby avoiding poor conductivity between the tab 22 and the top cover assembly 4. Furthermore, the opaque portion 11 of the insulating film 1 covering the soldering area also makes it easier to photograph and identify the opaque portion 11 when taking pictures of the soldering position of the tab 22 and the adapter 3 with a camera, thereby making it convenient to determine whether the soldering area is covered with the insulating film 1.

[0046] By attaching at least a portion of the transparent portion 12 to the main body 21, the tab 22 can still be observed even when it folds onto the main body 21. This allows for analysis of photographs taken of the area of ​​the tab 22 near the main body 21 and the area of ​​the main body 21 near the tab 22, significantly improving the efficiency and accuracy of detecting folded tabs. Furthermore, when the tab 22 folds onto the main body 21, it prevents a short circuit between the folded tab 22 and the housing 5 of the energy storage device 10, thus enhancing the safety of the energy storage device 10.

[0047] In related technologies, two separate insulating films 1 can be used between the transparent part 12 and the opaque part 11. However, when the two separate insulating films 1 are attached, their edges may overlap. If the overlapping area is small, it is easy for part of the solder area of ​​the tab 22 to be unattached. If the overlapping area is large, it is easy for the opaque insulating film 1 to be attached to the main body 21. As a result, even if the tab 22 is folded onto the main body 21, it may not be detected when photographed and inspected by a camera. In addition, the two insulating films 1 need to be attached twice, which increases the number of steps required to attach the insulating films 1, reduces efficiency, and increases costs.

[0048] Based on this, the insulating film 1 in this application has a transparent portion 12 and an opaque portion 11 integrally formed. Thus, the opaque portion 11 can be attached to the soldering area and at least a portion of the transparent portion 12 can be attached to the main body 21 in a single attachment operation. This not only facilitates the camera to take pictures of the soldering area, the area of ​​the tab 22 near the main body 21, and the area of ​​the main body 21 near the tab 22, but also facilitates the detection and judgment of whether the insulating film 1 is attached to the soldering area and whether the tab 22 is folded onto the main body 21, thereby improving the detection accuracy. It also simplifies the process of attaching the insulating film 1 and reduces costs.

[0049] At least a portion of the transparent portion 12 is attached to the main body 21. This can be either the transparent portion 12 being attached only to the main body 21, or a portion of the transparent portion 12 being attached to the area of ​​the tab 22 near the main body 21, while the other portion is attached to the main body 21. This is not a limitation.

[0050] Furthermore, as shown in Figure 4, the insulating film 1 can be wound into a roll, with both the transparent portion 12 and the opaque portion 11 extending along the winding direction of the insulating film 1. This allows the insulating film 1 to be cut according to the size of the solder area during application, enabling it to adapt to tabs 22 of different sizes. Alternatively, the insulating film 1 can be stacked. In this case, the size of the insulating film 1 can be customized according to the size of the solder area, eliminating the need for cutting during application and effectively simplifying the application process, thus improving efficiency.

[0051] The energy storage device 10 may include any one of the following: a secondary battery, a battery pack, a battery module, or a battery cluster; no limitation is made here. The following detailed description will be based on the example of the energy storage device 10 including a secondary battery.

[0052] The tabs 22 of the energy storage device 10, i.e. the tabs 22 of the secondary battery, may include a positive tab 222 and a negative tab 221. The adapter 3 includes a positive adapter 3a and a negative adapter 3b. The terminal 41 in the top cover assembly 4 includes a positive terminal and a negative terminal. The positive tab 222 is electrically connected to the positive terminal through the positive adapter 3a, and the negative tab 221 is electrically connected to the negative terminal through the negative adapter 3b.

[0053] When connecting the tab 22, adapter 3, and terminal 41, the positive adapter 3a is welded to the positive terminal, and the negative adapter 3b is welded to the negative terminal. Then, the adapter 3 and the battery cell 2 are placed side by side, with the end face of the battery cell 2 where the tab 22 is located facing the adapter 3. Then, the positive adapter 3a is welded to the positive tab 222 of the battery cell 2, and the negative adapter 3b is welded to the negative tab 221. Then, at the position where the positive adapter 3a is welded to the positive tab 222 and the body 21 of the battery cell 2 is close to the positive tab 222, the adapter 3a is welded to the positive tab 222. Insulating film 1 is adhered at the position of the negative adapter 3b and the negative tab 221, and at the position of the main body 21 of the cell 2 near 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 insulating film 1 can be bent together with the positive tab 222 and the negative tab 221.

[0054] Furthermore, the number of battery cells 2 can be one, two, or more, and is not limited here. For example, when there are two battery cells 2, there are two positive tabs 222 and two negative tabs 221. In this case, 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.

[0055] Optionally, as shown in Figures 2 and 3, the end face of the main body 21 is rectangular, and the end face of the main body 21 has a width direction (as shown by x in Figure 2). The adapter 3 has a pole post connection part 31 and two pole tab welding parts 32. The pole tab welding parts 32 are located on both sides of the pole post connection part 31 in the width direction. The soldering area is located in the middle area of ​​the pole tab welding parts 32. The opaque part 11 covers the pole tab welding parts 32.

[0056] This allows the edge of the tab welding portion 32 to be covered by the opaque portion 11, preventing burrs on the edge of the tab welding portion 32 from rubbing against the lower plastic in the top cover assembly 4 and falling into the body 21 of the cell 2. This avoids short circuits in the body 21 caused by burrs falling into it, and thus avoids low capacity of the cell 2 due to short circuits in the body 21.

[0057] The opaque portion 11 covering the tab welding portion 32 can be either exactly covering the tab welding portion 32, meaning the size of the opaque portion 11 is basically the same as the size of the tab welding portion 32; or the coverage area of ​​the opaque portion 11 is larger than the tab welding portion 32, meaning the size of the opaque portion is larger than the size of the tab welding portion 32. No limitation is made here.

[0058] In addition, after the tab 22 in the battery cell 2 is welded to the adapter 3, and before the tab 22 is bent, as shown in Figure 5, the insulating film 1 is rectangular, the transparent part 12 and the opaque part 11 are arranged along the direction of the main body 21 pointing to the tab 22, and the area of ​​the transparent part 12 is equal to the area of ​​the opaque part 11.

[0059] Therefore, the length of the transparent portion 12 is approximately the same as the length of the opaque portion 11, and the width of the transparent portion 12 is approximately the same as the width of the opaque portion 11, which facilitates the fabrication of the insulating film 1.

[0060] Furthermore, when cutting the insulating film 1, it is only necessary to make the size of the insulating film 1 along the arrangement direction perpendicular to the transparent part 12 and the opaque part 11 correspond to the size of the electrode welding part 32 and the electrode 22 of the adapter 3, which facilitates the cutting of the insulating film 1.

[0061] It should be explained that the term "rectangular" for the insulating film 1 means that the shape of the insulating film 1 is approximately rectangular, but does not necessarily mean that the shape of the insulating film 1 is always rectangular.

[0062] In other embodiments, when the tabs 22 in the battery cell 2 are welded to the adapter 3 and the tabs 22 are bent, as shown in FIG2, the insulating film 1 is L-shaped, and the angle between the plane where the transparent part 12 is located and the plane where the opaque part 11 is located on the side facing the battery cell 2 is 90° to 120°.

[0063] Therefore, after the tab 22 is bent, the insulating film 1 can easily affect the distance between the adapter 3 and the main body 21 of the cell 2. That is, the distance between the adapter 3 and the main body 21 of the cell 2 can still be small. This effectively prevents welding slag from falling onto the main body 21 and prevents the burrs on the adapter 3 from rubbing against the lower plastic on the top cover assembly 4. At the same time, it will not adversely affect the volume of the secondary battery, which is conducive to improving the energy ratio of the secondary battery.

[0064] It should be explained that the L-shaped shape of the insulating film 1 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 there is an angle between the opaque part 11 and the opaque part 12. The cross-section of the insulating film 1 along its own thickness direction is roughly L-shaped.

[0065] The angle between the plane where the transparent part 12 is located and the plane where the opaque part 11 is located, facing the side of the battery cell 2, can be 90°, 100°, 113°, 120°, etc., and is not limited here.

[0066] Furthermore, as shown in Figures 2, 5 and 6, the tab 22 has a tab bending area (as shown by the dashed box c in Figure 6). The dividing line between the transparent part 12 and the opaque part 11 is located in the tab bending area. The tab bending area is the area of ​​the tab 22 that is close to the main body 21 and is used to form a bend toward the adapter 3.

[0067] Therefore, when applying the insulating film 1, the position of the dividing line between the transparent part 12 and the opaque part 11 can be quickly identified through the tab bending area, so that the transparent part 12 and the opaque part 11 can be applied to the corresponding positions more quickly, which greatly improves the application efficiency of the insulating film 1.

[0068] The dividing line between the transparent portion 12 and the opaque portion 11 is located in the tab bending area. It should be understood that it is permissible for part of the transparent portion 12 to be attached to the tab bending area, and it is also permissible for part of the opaque portion 11 to be attached to the tab bending area.

[0069] The insulating film 1 described above can be implemented in various ways. In one possible implementation, the insulating film 1 may include a transparent substrate and an opaque substrate arranged side by side along the width direction of the insulating film 1. Both the transparent substrate and the opaque substrate are coated with an adhesive layer on the same side to facilitate the adhesion of the insulating film 1. The transparent substrate and the adhesive layer coated thereon can form the transparent portion 12 of the insulating film 1, and the opaque substrate and the adhesive layer coated thereon can form the opaque portion 11 of the insulating film 1. Thus, the same adhesive layer can be coated on both the transparent substrate and the opaque substrate, so that when making the insulating film 1, it is not necessary to distinguish the boundary line between the transparent substrate and the opaque substrate to directly apply the adhesive layer, which reduces the manufacturing difficulty of the insulating film 1.

[0070] In another possible implementation, as shown in FIG7, the insulating film 1 includes a transparent substrate 11a, the transparent substrate 11a having a first region (the region shown by the dashed frame d1 in FIG7) and a second region (the region shown by the dashed frame d2 in FIG7) arranged side by side, the first region being coated with an opaque adhesive layer 11b to form an opaque portion 11, and the second region being coated with a transparent adhesive layer 11c to form a transparent portion 12.

[0071] Therefore, the opaque part 11 and the transparent part 12 can be made from the same substrate, which reduces the manufacturing cost of the insulating film 1.

[0072] The transparent substrate 11a can be made of PET (polyethylene terephthalate), which gives the insulating film 1 good insulation and heat resistance, and also reduces the cost of the insulating film 1, thereby lowering the cost of the secondary battery. Of course, the transparent substrate 11a can also be made of PBT (polybutylene terephthalate), PE (polyethylene), etc., and is not limited here.

[0073] Alternatively, the opaque adhesive layer 11b can be an acrylic adhesive layer, allowing the insulating film 1 to adhere more firmly to the adapter 3, or to the tab 22 and the main body 21. Of course, the opaque adhesive layer 11b can also be a silicone pressure-sensitive adhesive, and this is not a limitation. The implementation of the transparent adhesive layer 11c is roughly the same as that of the opaque adhesive layer 11b, and will not be elaborated further here; it is sufficient that the transparent adhesive layer 11c is translucent while the opaque adhesive layer 11b is opaque.

[0074] Optionally, the light transmittance of the transparent portion 12 is greater than or equal to 30%.

[0075] Therefore, when taking pictures of the tab 22 with a camera, it is possible to clearly photograph and detect whether the tab 22 has folded onto the main body 21 through the transparent part 12, while also reducing the transparency requirements of the transparent part 12 and reducing costs.

[0076] It should be explained that the light transmittance mentioned above refers to the ability of light to pass through a medium. It is the percentage of light flux passing through a transparent or semi-transparent body to the incident light flux. In other words, the percentage between the light flux passing through the transparent part 12 and the light flux illuminating the transparent part 12 is the light transmittance of the transparent part 12.

[0077] The transmittance of the transparent portion 12 can be detected using a visible light transmittance meter, an ultraviolet light transmittance meter, or a haze transmittance meter. For example, when detecting the transmittance of the transparent portion 12 using a light transmittance meter, an 850nm infrared light source, a 940nm infrared light source, and a 550nm visible light source can be used to illuminate the transparent portion 12 of the insulating film 1 to be tested. The light transmittance meter sensor detects the incident light intensity and the transmitted light intensity after passing through the transparent portion 12, respectively. The percentage ratio between the transmitted light intensity and the incident light intensity is the transmittance of the transparent portion 12.

[0078] To facilitate the distinction between the transparent portion 12 and the tab 22, the color of the transparent portion 12 may optionally be a color other than the color of the tab 22 corresponding to the area where it is attached. That is, the color of the transparent portion 12 is different from the color of the tab 22 welded to the adapter 3 and covered by the corresponding opaque portion 11.

[0079] Therefore, when taking pictures to detect whether the tab 22 has folded onto the main body 21, the influence of the transparent part 12 on the judgment of whether the tab 22 has folded can be effectively reduced, so that the folded tab 22 can be easily judged, thus improving the accuracy of judging whether the tab 22 has folded.

[0080] For example, the tabs 22 in the battery cell 2 generally include a positive tab 222 and a negative tab 221. The positive tab 222 is generally made of aluminum or aluminum alloy, and the negative tab 221 is generally made of nickel, copper or copper alloy. That is, the color of the positive tab 222 is generally silver-white, which is the color of aluminum or aluminum alloy, and the negative tab 221 is generally silver-white, which is nickel-plated copper, or purplish-red or reddish-brown, which is the color of copper or copper alloy.

[0081] In order to make the color of the transparent part 12 different from the color of the tab 22, the transparent part 12 corresponding to the positive tab 222 can be any color other than the silver-white color of the aluminum foil, and the transparent part 12 corresponding to the negative tab 221 can be any color other than the silver-white color of the nickel foil or any color other than the purplish-red or reddish-brown color of the copper foil.

[0082] Furthermore, as shown in Figures 2-6, the tab 22 includes a positive tab 222 and a negative tab 221 arranged at intervals, and the color of the transparent part 12 is different from the color of the positive tab 222 and the negative tab 221.

[0083] Therefore, when attaching the insulating film 1, it is not necessary to select an insulating film 1 with a transparent part 12 of another color according to the color of the positive electrode tab 222 and the negative electrode tab 221. 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.

[0084] The color of the transparent part 12 can be any of gray, green, black, purple, etc.

[0085] Of course, the transparent part 12 can also be colorless; this is not a limitation.

[0086] In addition, the color of the opaque portion 11 can be at least one of blue, green, gray, black, etc.

[0087] This makes it easy to identify and photograph the opaque part 11, and the area of ​​the opaque part 11 can be easily determined from the photograph. This makes it easier to identify whether the opaque part 11 completely covers the solder area of ​​the adapter 3, and whether the opaque part 11 completely covers the solder area of ​​the tab 22 used for welding with the adapter 3. This further improves the efficiency and accuracy of detecting and identifying whether the solder area is covered by the insulating film 1 by taking a picture with a camera.

[0088] Of course, the opaque part 11 can also be opaque white, and this is not a limitation.

[0089] Optionally, 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 taking pictures for inspection by camera, thereby improving the inspection efficiency.

[0090] Optionally, as shown in Figures 2 and 5, the end face of the main body 21 is rectangular, and the end face of the main body 21 has a length direction (as shown by y in Figure 5). The electrode tab 22 includes positive electrode tabs 222 and negative electrode tabs 221 arranged at intervals along the length direction. The insulating film 1 includes a first insulating film 1a corresponding to the positive electrode tab 222 and a second insulating film 1b corresponding to the negative electrode tab 221. The dimension of the first insulating film 1a along the length direction is greater than or equal to the dimension of the positive electrode tab 222 along the length direction, and the dimension of the second insulating film 1b along the length direction is greater than or equal to the dimension of the negative electrode tab 221 along the length direction.

[0091] Therefore, when the first insulating film 1a is adhered, it can cover the solder area of ​​the corresponding adapter 3 and also cover the positive electrode tab 222 along the length direction to prevent short circuits between the area of ​​the positive electrode tab 222 near the main body 21 and the top cover assembly 4 or between the positive and negative electrode plates in the main body 21. When the second insulating film 1b is adhered, it can cover the solder area of ​​the corresponding adapter 3 and also cover the negative electrode tab 221 along the length direction to prevent short circuits between the area of ​​the negative electrode tab 221 near the main body 21 and the top cover assembly 4 or between the positive and negative electrode plates in the main body 21, effectively improving the safety of the battery cell 2.

[0092] Optionally, the first insulating film 1a is larger in length than the positive electrode tab 222, and the second insulating film 1b is larger in length than the negative electrode tab 221. This way, when attaching the insulating film 1, it is not necessary to pay special attention to ensuring that the edge of the first insulating film 1a is flush with the edge of the positive electrode tab 222, and that the edge of the second insulating film 1b is flush with the edge of the negative electrode tab 221.

[0093] In addition, the dimension of the opaque portion 11 of the insulating film 1 along the width direction of the end face of the main body 21 can be greater than or equal to the dimension along the width direction of the area of ​​the tab 22 used for welding with the adapter 3, so that when the insulating film 1 is attached, the opaque portion 11 can completely cover the area of ​​the tab 22 used for welding with the adapter 3.

[0094] The dimension of the opaque portion 11 along the width direction can be smaller than or equal to the dimension of the tab 22 along the width direction, so that while the opaque portion 11 can cover the area of ​​the tab 22 used for welding with the adapter 3, the size of the opaque portion 11 can also be reduced, thereby reducing costs.

[0095] Optionally, the first insulating film 1a and the second insulating film 1b are spaced apart along the length direction.

[0096] This reduces the amount of insulating film 1 used, lowers costs, and compared to the way the insulating film 1 attached to the positive electrode tab 222 and the insulating film 1 attached to the negative electrode tab 221 are connected to each other, it can prevent the insulating film 1 from interfering with other structures in the secondary battery, such as interfering with the lower plastic in the top cover assembly 4.

[0097] Along the direction from the main body 21 to the tab 22, the size of the transparent part 12 is greater than or equal to the size of the tab 22.

[0098] 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 short-circuiting with the secondary battery casing 5 because it is partially not covered by the insulating film 1, thereby improving the safety of the secondary battery with the cell 2 assembled thereon.

[0099] It should be explained that the direction from the main body 21 to the tab 22 mentioned above can be along the height direction of the cell 2. For example, when the cell 2 is a square cell 2, the direction from the main body 21 to the tab 22 can be parallel to the height direction of the cell 2, as shown by z in Figures 2 and 5.

[0100] This embodiment also provides an electrical system 100, as shown in FIG8, which includes the energy storage device 10 described in the above embodiment.

[0101] In this embodiment, the energy storage device 10 of the power system 100 is the energy storage device 10 described in the above embodiments. Therefore, the energy storage device 10 in this embodiment has the technical effects of the energy storage device 10 in the above embodiments. Since the technical effects of the energy storage device 10 have been fully explained in the above embodiments, they will not be repeated here.

[0102] In addition, the power system 100 may also include a power conversion device 20 and an electrical load 30. The power conversion device 20 is used to convert other forms of energy into electrical energy. The energy storage device 10 is able to store at least a portion of the electrical energy converted by the power conversion device 20. The energy storage device 10 is also used to provide electrical energy to the electrical load 30, such as household appliances and street lights. When the power grid is interrupted or there is a power outage, the energy storage device 10 can supply power to the household appliances and street lights.

[0103] In addition, the power conversion device 20 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy and mechanical energy into electrical energy. The power conversion device 20 can be a solar panel, windmill, geothermal power generation device, etc.

[0104] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0105] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims. Industrial applicability

[0106] The energy storage device and power system provided in this application can not only easily identify whether the electrode tabs are folded, effectively improving the detection efficiency and accuracy of electrode tab folding, but also easily identify whether the solder joints of the electrode tabs are covered with insulating film, which has strong industrial applicability.

Claims

1. An energy storage device, characterized in that, include: A battery cell, the battery cell comprising a body and tabs disposed on the end face of the body; A housing having a cavity open at one end for accommodating the battery cell; A top cover assembly that closes the opening of the housing, the top cover assembly having a pole post; An adapter is disposed between the top cover assembly and the battery cell. One end of the adapter is welded to the tab and the other end is connected to the pole post. The adapter has a solder area on the side surface opposite to the tab along its own thickness direction. as well as An insulating film comprising an integrally formed transparent portion and an opaque portion, wherein the opaque portion covers the soldering area and at least a portion of the transparent portion is attached to the body.

2. The energy storage device according to claim 1, characterized in that, The end face of the main body is rectangular and has a width direction. The adapter has a pole connection part and two electrode tab welding parts. The electrode tab welding parts are located on both sides of the pole connection part in the width direction. The soldering area is located in the middle area of ​​the electrode tab welding parts. The opaque part covers the electrode tab welding parts.

3. The energy storage device according to claim 2, characterized in that, The insulating film is rectangular, and the transparent portion and the opaque portion are arranged along the body towards the tab, with the area of ​​the transparent portion being equal to the area of ​​the opaque portion.

4. The energy storage device according to claim 2, characterized in that, The insulating film is L-shaped, and the angle between the plane containing the transparent portion and the plane containing the opaque portion toward the side facing the battery cell is 90° to 120°.

5. The energy storage device according to claim 4, characterized in that, The electrode tab has an electrode tab bending area, and the dividing line between the transparent part and the opaque part is located in the electrode tab bending area. The electrode tab bending area is the area where the electrode tab is close to the main body and is used to form a bend toward the adapter.

6. The energy storage device according to any one of claims 1-5, characterized in that, The insulating film includes a transparent substrate having 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 portion, and the second region is coated with a transparent adhesive layer to form the transparent portion.

7. The energy storage device according to any one of claims 1-5, characterized in that, The light transmittance of the transparent portion is greater than or equal to 30%.

8. The energy storage device according to any one of claims 1-5, characterized in that, The color of the transparent part is a color other than the color of the tab corresponding to the area where it is attached.

9. The energy storage device according to claim 8, characterized in that, The electrode tabs include positive and negative electrode tabs arranged at intervals, and the color of the transparent part is different from the color of the positive electrode tab and the color of the negative electrode tab.

10. The energy storage device according to claim 8, characterized in that, The color of the opaque portion is at least one of blue, green, gray, and black.

11. The energy storage device according to any one of claims 1-5, characterized in that, The end face of the main body is rectangular and has a length direction. The electrode includes positive electrode and negative electrode arranged at intervals along the length direction. The insulating film includes a first insulating film corresponding to the positive electrode and a second insulating film corresponding to the negative electrode. The dimension of the first insulating film along the length direction is greater than or equal to the dimension of the positive electrode along the length direction, and the dimension of the second insulating film along the length direction is greater than or equal to the dimension of the negative electrode along the length direction.

12. The energy storage device according to claim 11, characterized in that, The first insulating film and the second insulating film are spaced apart along the length direction.

13. The energy storage device according to any one of claims 1-5, characterized in that, Along the direction from the main body to the tab, the size of the transparent portion is greater than or equal to the size of the tab.

14. An electrical system, characterized in that, Includes the energy storage device as described in claim 1.

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