Battery cell, battery pack and electric equipment

Abstract

The utility model discloses a battery cell, a battery pack and electric equipment. A shell, wherein the pole core is arranged in the shell; wherein at least partial area of the inner surface of the shell is provided with a blind hole, and the blind hole is filled with a positive electrode material; the battery cell further comprises a diaphragm, the diaphragm is used for electronic insulation and ion conduction, and the diaphragm covers the blind hole so as to isolate the pole core from the positive electrode material. According to the battery cell, the battery pack and the electric equipment provided by the invention, the real charge state of the battery cell can be accurately reflected through the reference electrode formed by the cathode of the battery cell and the anode material filled in the blind hole, and the blind hole of the shell is filled with the anode material; therefore, the positive electrode material filled in the blind hole is corroded preferentially under the condition that the shell and the negative electrode are short-circuited or slightly short, so that the shell is protected, the shell is prevented from being corroded and leaking liquid, and the safety of the battery cell is improved.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and more specifically to a battery cell, a battery pack and an electrical device. Background Art

[0002] In the related art, the battery state of charge (SOC) can be calculated in static or dynamic conditions. In static conditions, the state of charge of the lithium-ion battery is usually reflected by collecting the static voltage of the positive and negative electrodes of the lithium-ion battery when the vehicle stops running, and in dynamic conditions, the state of charge of the lithium-ion battery is usually reflected by integrating the charging or discharging power of the lithium-ion battery during the use of the lithium-ion battery.

[0003] However, the method of reflecting the charge state of the lithium-ion battery by collecting the static voltage of the positive and negative electrodes of the lithium-ion battery can only be used in a static state, and cannot be used in a dynamic state. The scope of use is limited, and as the capacity of the lithium-ion battery decays, the test data will be inaccurate and cannot accurately reflect the charge state of the lithium-ion battery. The method of reflecting the charge state of the lithium-ion battery by integrating the charge or discharge power of the lithium-ion battery cannot accurately reflect the charge state of the lithium-ion battery when the lithium-ion battery capacity changes due to abnormal conditions such as lithium deposition.

[0004] In view of the above-mentioned technical problems, the present application provides a new battery cell, battery pack and electrical equipment. Utility Model Content

[0005] The present application is proposed to solve at least one of the above problems. According to one aspect of the present application, a battery cell is provided, the battery cell comprising: a pole core; a shell, the pole core is arranged in the shell; wherein at least a part of the inner surface of the shell is provided with a blind hole, the blind hole is filled with a positive electrode material; the battery cell also includes an insulating film, the diaphragm is used for electronic insulation and ion conduction, the insulating film covers the blind hole to isolate the pole core and the positive electrode material.

[0006] In some embodiments of the present application, the battery cell further includes a sampling point, and the sampling point is used to connect a sampling circuit to collect the voltage between the negative electrode of the battery cell and the positive electrode material.

[0007] In some embodiments of the present application, the shell includes a main shell and a cover plate, and the main shell is provided with an opening for exposing the pole core; the cover plate is arranged at the opening to close the opening.

[0008] In some embodiments of the present application, the blind hole is provided on at least a portion of the inner surface of the main shell.

[0009] In some embodiments of the present application, the main shell is a rectangular shell, which includes a first side wall and a second side wall connected to each other, and the area of ​​the first side wall is larger than the area of ​​the second side wall; wherein the blind hole is provided on at least a portion of the inner surface of the first side wall; and / or the blind hole is provided on at least a portion of the inner surface of the second side wall.

[0010] In some embodiments of the present application, the cover plate is an integral structure, and the blind hole is provided on at least a portion of the inner surface of the cover plate of the integral structure; or, the cover plate includes a positive cover plate and a negative cover plate, and the blind hole is provided on at least a portion of the inner surface of the negative cover plate.

[0011] In some embodiments of the present application, an explosion-proof valve is provided on the cover plate, and the blind hole is provided close to the explosion-proof valve; or, an explosion-proof valve is provided on the negative electrode cover plate, and the blind hole is provided close to the explosion-proof valve.

[0012] In some embodiments of the present application, the shell further includes a partition disposed between the main shell and the pole core, the partition being electrically connected to the main shell or the cover plate, and the blind hole being disposed on at least a portion of the surface of the partition facing the pole core.

[0013] In some embodiments of the present application, the cover plate is an integrated structure, a negative electrode pole is arranged on the cover plate of the integrated structure, and the battery cell also includes a sampling point, and the sampling point is used to connect a sampling circuit to collect the voltage between the negative electrode pole and the cover plate; or, the cover plate includes a positive cover plate and a negative cover plate, and a negative electrode pole electrically connected to the negative electrode layer is arranged on the negative cover plate, and the battery cell also includes a sampling point, and the sampling point is used to connect a sampling circuit to collect the voltage between the negative electrode pole and the negative cover plate.

[0014] In some embodiments of the present application, the state of charge of the positive electrode material is 30% to 50%.

[0015] In some embodiments of the present application, the size of the blind hole is 0.1 mm to 0.2 mm.

[0016] According to another aspect of the present application, a battery pack is provided, comprising the battery cell described in any one of the above.

[0017] In some embodiments of the present application, the battery pack further includes a sampling circuit, which is connected to the battery pack to collect the voltage between the negative electrode and the positive electrode material of the battery cell in the battery pack.

[0018] According to another aspect of the present application, there is provided an electrical device, which includes the electrical device and the battery pack, wherein the battery pack is used to provide electrical energy to the electrical device.

[0019] According to the battery cells, battery packs and electrical equipment of the embodiments of the present application, a blind hole is provided on at least a portion of the inner surface of the shell, a positive electrode material is filled in the blind hole as a reference electrode of the three electrodes, and an electronically insulating and ion-conductive diaphragm is used to cover the blind hole to isolate the electrode core and the positive electrode material. Since the change in the battery cell voltage is mainly reflected in the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole is very stable, whether the capacity of the battery cell decays in a static state or the capacity of the battery cell changes due to abnormal conditions such as lithium deposition in the battery cell in a dynamic state, the actual charge state of the battery cell can be accurately reflected by the reference electrode formed by the negative electrode of the battery cell and the positive electrode material filled in the blind hole.

[0020] Moreover, since the blind holes of the shell are filled with positive electrode materials, the positive electrode materials filled in the blind holes will be corroded preferentially when the shell and the negative electrode are short-circuited or slightly shorted, thereby protecting the shell, avoiding corrosion and leakage of the shell, and improving the safety of the battery cell.

[0021] Furthermore, the positive electrode material is filled in the blind hole on the inner surface of the battery cell shell and will not occupy other space in the shell, thereby improving the space utilization of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] By describing the embodiments of the present application in more detail in conjunction with the accompanying drawings, the above and other purposes, features and advantages of the present application will become more apparent. The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0023] Figure 1 A schematic diagram of an explosion of a battery cell provided according to an embodiment of the present application is shown.

[0024] Figure 2 A schematic structural diagram of a main housing provided according to an embodiment of the present application is shown.

[0025] Figure 3 A schematic structural diagram showing a blind hole is provided on the inner surface of the first side wall of the main shell according to an embodiment of the present application.

[0026] Figure 4 A schematic structural diagram of a negative electrode cover plate provided according to an embodiment of the present application is shown.

[0027] Figure 5An exploded schematic diagram of a negative electrode cover plate provided according to an embodiment of the present application is shown.

[0028] Figure 6 A schematic diagram of the negative electrode cover plate and a partially enlarged structure thereof provided according to an embodiment of the present application is shown.

[0029] In the attached figure:

[0030] 100 cells;

[0031] 110 pole core;

[0032] 121 main shell;

[0033] 1211 first side wall;

[0034] 1212 second side wall;

[0035] 131 negative electrode cover;

[0036] 132 negative pole;

[0037] 133 explosion-proof valve;

[0038] 141 positive electrode cover;

[0039] 142 positive pole;

[0040] 150 blind holes. DETAILED DESCRIPTION

[0041] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present application. However, it is apparent to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present application, some technical features well known in the art are not described.

[0042] It should be understood that the present application can be implemented in different forms and should not be construed as being limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete and fully convey the scope of the present application to those skilled in the art. In the accompanying drawings, the sizes and relative sizes of layers and regions may be exaggerated for clarity. The same reference numerals throughout represent the same elements.

[0043] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present application, the first element, component, region, layer or part discussed below can be represented as a second element, component, region, layer or part.

[0044] Spatially relative terms such as "under," "below," "below," "under," "above," "above," etc., may be used herein for ease of description to describe the relationship of an element or feature shown in the figures to other elements or features. It should be understood that in addition to the orientations shown in the figures, the spatially relative terms are intended to include different orientations of the device in use and operation. For example, if the device in the accompanying drawings is flipped, then the elements or features described as "under other elements" or "under" or "under" will be oriented as "on" the other elements or features. Therefore, the exemplary terms "under" and "under" may include both upper and lower orientations. The device may be oriented otherwise (rotated 90 degrees or other orientations) and the spatial descriptors used herein are interpreted accordingly.

[0045] In the related art, the battery state of charge (SOC) can be calculated in static or dynamic conditions. In static conditions, the state of charge of the lithium-ion battery is usually reflected by collecting the static voltage of the positive and negative electrodes of the lithium-ion battery when the vehicle stops running, and in dynamic conditions, the state of charge of the lithium-ion battery is usually reflected by integrating the charging or discharging power of the lithium-ion battery during the use of the lithium-ion battery.

[0046] However, the method of reflecting the charge state of the lithium-ion battery by collecting the static voltage of the positive and negative electrodes of the lithium-ion battery can only be used in a static state, and cannot be used in a dynamic state. The scope of use is limited, and as the capacity of the lithium-ion battery decays, the test data will be inaccurate and cannot accurately reflect the charge state of the lithium-ion battery. The method of reflecting the charge state of the lithium-ion battery by integrating the charge or discharge power of the lithium-ion battery cannot accurately reflect the charge state of the lithium-ion battery when the lithium-ion battery capacity changes due to abnormal conditions such as lithium deposition.

[0047] In order to solve at least one of the above problems, the present application provides a battery cell, which includes: a pole core; a shell, wherein the pole core is arranged in the shell; wherein a blind hole is provided on at least a portion of the inner surface of the shell, and the blind hole is filled with a positive electrode material; the battery cell also includes a diaphragm, which is used for electronic insulation and ion conduction, and the diaphragm covers the blind hole to isolate the pole core and the positive electrode material.

[0048] According to the battery cell of the present application, a blind hole is provided on at least a portion of the inner surface of the shell, a positive electrode material is filled in the blind hole as a reference electrode of the three electrodes, and an electronically insulating and ion-conductive diaphragm is used to cover the blind hole to isolate the electrode core and the positive electrode material. Since the change of the battery cell voltage is mainly reflected in the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole is very stable, therefore, whether the capacity of the battery cell decays in a static state or the capacity of the battery cell changes due to abnormal conditions such as lithium deposition in the battery cell in a dynamic state, the actual charge state of the battery cell can be accurately reflected by the reference electrode formed by the negative electrode of the battery cell and the positive electrode material filled in the blind hole.

[0049] Moreover, since the blind holes of the shell are filled with positive electrode materials, the positive electrode materials filled in the blind holes will be corroded preferentially when the shell and the negative electrode are short-circuited or slightly shorted, thereby protecting the shell, avoiding corrosion and leakage of the shell, and improving the safety of the battery cell.

[0050] Furthermore, the positive electrode material is filled in the blind hole on the inner surface of the battery cell shell and will not occupy other space in the shell, thereby improving the space utilization of the battery cell.

[0051] In order to thoroughly understand the present application, a detailed structure will be presented in the following description to illustrate the technical solution proposed by the present application. The preferred embodiments of the present application are described in detail as follows, but in addition to these detailed descriptions, the present application may also have other implementation methods.

[0052] Reference below Figure 1 to Figure 6A battery cell 100 according to an embodiment of the present application is described. The battery cell 100 provided in the embodiment of the present application includes: a pole core 110; a shell, wherein the pole core 110 is disposed in the shell; wherein a blind hole 150 is disposed on at least a portion of the inner surface of the shell, and the blind hole 150 is filled with a positive electrode material; the battery cell 100 also includes a diaphragm, which is used for electronic insulation and ion conduction, and the diaphragm covers the blind hole 150 to isolate the pole core 110 from the positive electrode material.

[0053] It can be understood that the pole core 110 can be constructed by winding, laminating, etc., with an insulating layer provided between adjacent positive and negative electrode layers, wherein the insulating layer can be the same as or different from the material of the diaphragm used to isolate the pole core 110 and the positive electrode material, and this is not limited. After the positive electrode material is filled in the blind hole 150, the blind hole 150 is covered by a diaphragm, which can achieve the functions of electronic insulation and ion conduction, so that ion exchange can be achieved between the positive electrode material filled in the blind hole 150 and the pole core 110, but the positive electrode material filled in the blind hole 150 and the pole core 110 are electronically insulated to avoid short circuit between the positive electrode material filled in the blind hole 150 and the negative electrode layer of the pole core 110.

[0054] The positive electrode material filled in the blind hole 150 can be used as a reference electrode to form three electrodes together with the positive and negative electrodes of the battery cell. Since the change in the voltage of the battery cell 100 is mainly reflected at the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole 150 is very stable, the reference electrode formed by the negative electrode of the battery cell 100 and the positive electrode material filled in the blind hole 150 can reflect the actual potential level of the positive and negative electrodes of the battery cell 100, and thus reflect the actual charge state of the battery cell 100.

[0055] It is worth pointing out that the method of reflecting the real state of charge of the battery cell 100 through the reference electrode formed by the negative electrode of the battery cell 100 and the positive electrode material filled in the blind hole 150 in this embodiment can be used not only in static state but also in dynamic state. When used in static state, since the voltage of the reference electrode formed by the positive electrode material filled in the blind hole 150 is very stable, the change of the voltage of the battery cell 100 is mainly reflected in the negative electrode. Therefore, even if the capacity of the battery cell 100 decays, the real state of charge of the battery cell 100 can be accurately reflected through the reference electrode formed by the negative electrode of the battery cell 100 and the positive electrode material filled in the blind hole 150. When used in a dynamic state, even if abnormal conditions such as lithium deposition occurs in the battery cell 100, causing the capacity of the battery cell 100 to change, the positive electrode material filled in the blind hole 150 is not affected, and the voltage of the reference electrode formed is still very stable. Therefore, the reference electrode formed by the negative electrode of the battery cell 100 and the positive electrode material filled in the blind hole 150 can still accurately reflect the actual charge state of the battery cell 100, and can assist in determining whether lithium deposition occurs in the battery cell 100.

[0056] Based on this, the present application provides a battery cell 100 that can collect the true state of charge both in static and dynamic conditions. According to the battery cell 100 of the present application, by setting a blind hole 150 on at least part of the area of ​​the shell, the positive electrode material is filled in the blind hole 150 as the reference electrode of the three electrodes, and the blind hole 150 is covered with an electronically insulating and ion-conductive diaphragm to isolate the electrode core and the positive electrode material. Since the change in the voltage of the battery cell 100 is mainly reflected in the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole 150 is very stable, whether the capacity of the battery cell 100 decays in static conditions, or when the capacity of the battery cell 100 changes due to abnormal conditions such as lithium deposition in the battery cell 100 in dynamic conditions, the true state of charge of the battery cell 100 can be accurately reflected by the reference electrode formed by the negative electrode of the battery cell 100 and the positive electrode material filled in the blind hole 150.

[0057] Moreover, since the blind hole 150 of the shell is filled with positive electrode material, the positive electrode material filled in the blind hole 150 will be corroded first when the shell and the negative electrode are short-circuited or slightly shorted, thereby protecting the shell, avoiding corrosion and leakage of the shell, and improving the safety of the battery cell 100.

[0058] Furthermore, the positive electrode material is filled in the blind hole 150 on the inner surface of the shell of the battery cell 100 , and will not occupy other space in the shell, thereby improving the space utilization of the battery cell 100 .

[0059] In some embodiments, the positive electrode material may include lithium ferrous phosphate, lithium titanate, or lithium ferrous phosphate, lithium titanate, etc. for fixing the SOC, and this is not limited. Among them, the state of charge of the positive electrode material can be adjusted to 30% to 50%, for example, the state of charge of the positive electrode material is 30%, 40%, 50%, etc., and this is not limited. Since the blind hole 150 of the shell is filled with lithium ferrous phosphate, lithium titanate, or lithium ferrous phosphate, lithium titanate, etc. for fixing the SOC, the lithium ferrous phosphate, lithium titanate, or lithium ferrous phosphate, lithium titanate, etc. positive electrode materials filled in the blind hole 150 will be corroded preferentially in the case of a short circuit or micro-short between the shell and the negative electrode, thereby protecting the shell, avoiding corrosion and leakage of the shell, and improving the safety of the battery cell 100.

[0060] In some embodiments, the diaphragm may be ceramic, PE diaphragm or other electronically insulating and ion-conducting materials, which are not limited.

[0061] In some embodiments, the shell includes a main shell and a cover plate, the main shell is provided with an opening for exposing the pole core, and the cover plate is provided at the opening to close the opening.

[0062] Among them, an opening can be set at one end of the main shell, and the shell only includes an integrated cover plate, on which the positive electrode column and the negative electrode column are arranged. After the cover plate closes the opening, the positive electrode column and the negative electrode column are respectively connected to the positive electrode layer and the negative electrode layer of the electrode core to lead the electrode to the outside.

[0063] Alternatively, openings may be provided at both ends of the main shell, one end being a positive electrode opening and the other end being a negative electrode opening. Accordingly, the shell includes two covers, namely a positive electrode cover and a negative electrode cover. A positive electrode column is provided on the positive electrode cover, and a negative electrode column is provided on the negative electrode cover. After the positive electrode cover seals the positive electrode opening and the negative electrode cover seals the negative electrode opening, the positive electrode column and the negative electrode column are respectively connected to the positive electrode layer and the negative electrode layer of the electrode core to lead the electrode to the outside. For example, Figure 1 As shown, the shell includes a main shell 121, a positive electrode cover plate 141 and a negative electrode cover plate 131. The main shell 121 is provided with a positive electrode opening for exposing the positive end of the electrode core 110 and a negative electrode opening for exposing the negative end of the electrode core 110; the positive electrode cover plate 141 is provided at the positive electrode opening to close the positive electrode opening, and the negative electrode cover plate 131 is provided at the negative electrode opening to close the negative electrode opening. After the electrode core 110 is provided in the main shell 121, the positive electrode opening is closed by the positive electrode cover plate 141, and the negative electrode opening is closed by the negative electrode cover plate 131. After the electrolyte is poured, leakage of the electrolyte can be avoided. Moreover, a positive electrode column 142 is provided on the positive electrode cover 141, and the positive electrode column 142 is electrically connected to the positive electrode layer in the electrode core 110. A negative electrode column 132 is provided on the negative electrode cover 131, and the negative electrode column 132 is electrically connected to the negative electrode layer in the electrode core 110. The electric energy stored in the electrode core 110 can be led out to the outside through the positive electrode column 142 and the negative electrode column 132, or the outside can charge and store energy in the electrode core 110 through the positive electrode column 142 and the negative electrode column 132. Among them, the main shell 121 can be an aluminum shell, an iron shell, etc., which is not limited.

[0064] It can be understood that the blind hole 150 filled with positive electrode material can be set on the inner surface of the main shell 121 or on the inner surface of the negative electrode cover 131, and there is no limitation on this. The size of the blind hole 150 can be 0.1 mm to 0.2 mm, such as 0.1 mm, 0.15 mm, 0.2 mm, etc., and there is no limitation on this. When the blind hole 150 is set on the inner surface of the main shell 121 and / or the inner surface of the negative electrode cover 131, the number of the blind holes 150 can be multiple, and the multiple blind holes 150 can be evenly or unevenly distributed, and there is no limitation on this.

[0065] In some embodiments, the battery cell 100 further includes a sampling point, which is used to connect a sampling circuit to collect the voltage between the negative electrode and the positive electrode material of the battery cell 110. Since the change in the voltage of the battery cell 100 is mainly reflected at the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole 150 is very stable, the voltage between the negative electrode and the positive electrode material of the battery cell 100 can accurately reflect the true potential level of the positive and negative electrodes of the battery cell 100, so as to assist in determining the true state of charge of the battery cell 100 and whether lithium plating occurs.

[0066] Furthermore, when the battery cell 100 includes only an integrated cover plate, the sampling point can be located on the negative electrode pole 132 and the integrated cover plate, and the sampling circuit connected to the sampling point can be used to collect the voltage between the negative electrode pole 132 and the integrated cover plate, thereby reflecting the voltage between the negative electrode and the positive electrode materials of the battery cell 100.

[0067] Alternatively, when the battery cell includes a positive electrode cover 141 and a negative electrode cover 131, the sampling point may be located on the negative electrode column 132 and the negative electrode cover 131, and the sampling circuit connected to the sampling point may be used to collect the voltage between the negative electrode column 132 and the negative electrode cover 131, thereby reflecting the voltage between the negative electrode and the positive electrode material of the battery cell 100. That is, the sampling circuit is connected to the negative electrode column 132 and the negative electrode cover 131 through the sampling point, respectively, to achieve voltage collection.

[0068] In some embodiments, a blind hole 150 may be provided on at least a portion of the inner surface of the main housing 121 .

[0069] Taking the main housing 121 as a rectangular housing as an example, Figure 2As shown, the rectangular housing includes a first side wall 1211 and a second side wall 1212 connected to each other, the area of ​​the first side wall 1211 is larger than the area of ​​the second side wall 1212, the first side wall 1211 can be called the large surface of the main housing 121, and the second side wall 1212 can be called the small surface of the main housing 121. In one example, the blind hole 150 can be provided on at least a portion of the inner surface of the first side wall 1211. In another example, the blind hole 150 can also be provided on at least a portion of the inner surface of the second side wall 1212. After the blind hole 150 is set on the first side wall 1211 and / or the second side wall 1212 of the main shell 121, the positive electrode material is filled in the blind hole 150 as a reference electrode of the three electrodes, and the blind hole 150 is covered with a diaphragm to isolate the electrode core 110 and the positive electrode material, thereby achieving insulation between the positive electrode material filled in the blind hole 150 and the electrode core 110. Then, a sampling circuit can be arranged on the battery cell 100, and the sampling points on the battery cell 100 are connected through the sampling circuit to detect the voltage of the positive electrode layer and the negative electrode layer of the electrode core 110 to the main shell 121. As described above, the sampling circuit is connected to the negative pole 132 and the cover plate through the sampling points, and the sampling circuit connected to the negative pole 132 realizes the detection of the voltage of the negative pole of the battery cell 100. Since the main shell 121 is welded to the cover plate, and the inner surface of the main shell 121 is provided with a blind hole 150 filled with positive electrode material, the sampling circuit connected to the cover plate realizes the voltage detection of the positive electrode material filled in the blind hole 150. Since the change of the voltage of the battery cell 100 is mainly reflected in the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole 150 is very stable, it can accurately reflect the real potential level of the positive and negative electrodes of the battery cell 100, so as to assist in judging the real charge state of the battery cell 100 and whether lithium deposition occurs. Moreover, in the case of a short circuit or a slight short between the main shell 121 and the negative electrode, the positive electrode material filled in the blind hole 150 will be corroded first, thereby protecting the main shell 121, avoiding corrosion and leakage of the main shell 121, and improving the safety of the battery cell 100.

[0070] For example, Figure 3 As shown, taking the main shell 121 as an aluminum shell as an example, a plurality of evenly distributed blind holes 150 with a diameter of 0.1 mm are set on the large surface of the aluminum shell, and the blind holes 150 are filled with lithium iron phosphate positive electrode slurry, and a layer of PE film is thermally coated. After the battery cell 100 is filled with liquid, the aluminum shell and the negative electrode of the battery cell 100 are charged, and the charge state of the lithium iron phosphate dressing is adjusted to 50% SOC.

[0071] In some embodiments, a blind hole 150 may be provided on at least a portion of the inner surface of the cover plate.

[0072] Among them, when the battery cell 100 includes only one cover plate of an integral structure, a blind hole 150 may be provided on at least a partial area of ​​the inner surface of the cover plate of the integral structure; or, when the battery cell 100 includes a positive cover plate 141 and a negative cover plate 131, a blind hole 150 may be provided on at least a partial area of ​​the inner surface of the negative cover plate 131.

[0073] Taking the example of a blind hole 150 provided on at least a portion of the inner surface of the negative electrode cover 131, the blind hole 150 is filled with a positive electrode material as a reference electrode of the three electrodes, and the blind hole 150 is covered with a diaphragm to isolate the electrode core 110 and the positive electrode material, thereby achieving insulation between the positive electrode material filled in the blind hole 150 and the electrode core 110. Then, a sampling circuit can be arranged on the battery cell 100, and the sampling points on the battery cell 100 are connected through the sampling circuit to detect the voltage of the positive electrode layer and the negative electrode layer of the electrode core 110 to the negative electrode cover 131. As described above, the sampling circuit is connected to the negative pole 132 and the negative cover 131 through the sampling points, and the sampling circuit connected to the negative pole 132 detects the voltage of the negative pole of the battery cell 100. Since the main shell 121 is welded to the negative cover 131, and the inner surface of the main shell 121 is provided with a blind hole 150 filled with positive electrode material, the sampling circuit connected to the negative cover 131 detects the voltage of the positive electrode material filled in the blind hole 150. Since the change of the voltage of the battery cell 100 is mainly reflected in the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole 150 is very stable, it can accurately reflect the real potential level of the positive and negative electrodes of the battery cell 100, so as to assist in judging the real state of charge of the battery cell 100 and whether lithium deposition occurs. Moreover, when the negative electrode cover 131 is short-circuited or slightly shorted to the negative electrode, the positive electrode material filled in the blind hole 150 will be corroded first, thereby protecting the negative electrode cover 131, avoiding corrosion and leakage of the negative electrode cover 131, and improving the safety of the battery cell 100.

[0074] Accordingly, it can be understood that when the blind hole 150 is provided on at least a portion of the inner surface of the integrated cover plate, the integrated cover plate can be protected on the basis of accurately reflecting the actual charge state of the battery cell 100 .

[0075] Furthermore, the cover plate is provided with an explosion-proof valve 133, and the blind hole 150 can be provided close to the explosion-proof valve 133, so as to protect the explosion-proof valve 133 and prevent the explosion-proof valve 133 from being corroded. Specifically, when the cover plate is a cover plate of an integral structure, the explosion-proof valve 133 is located on the cover plate of the integral structure, the blind hole 150 is provided close to the explosion-proof valve 133, and the positive electrode material filled in the blind hole 150 can prevent the explosion-proof valve 133 on the cover plate of the integral structure from being corroded; when the cover plate includes a positive electrode cover plate 141 and a negative electrode cover plate 131, the explosion-proof valve 133 is located on the negative electrode cover plate 131, the blind hole 150 is provided close to the explosion-proof valve 133, and the positive electrode material filled in the blind hole 150 can prevent the explosion-proof valve 133 on the negative electrode cover plate 131 from being corroded.

[0076] For example, Figure 6 As shown, a plurality of evenly distributed blind holes 150 with a diameter of 0.1 to 0.2 mm can be provided near the explosion-proof valve 133 of the negative electrode cover plate 131, and the blind holes 150 are filled with lithium iron phosphate positive electrode slurry and thermally coated with a layer of PE film. After the battery cell 100 is filled with liquid, the main shell 121 and the negative electrode of the battery cell 100 are charged, and the state of charge of the lithium iron phosphate dressing is adjusted to 50% SOC.

[0077] In some embodiments, the shell further includes a partition disposed between the main shell 121 and the pole core, the partition is electrically connected to the main shell 121 or the cover plate, and a blind hole 150 is disposed on at least a portion of the surface of the partition facing the pole core.

[0078] Among them, for the cover plate of the integrated structure, the cover plate of the integrated structure is welded to the main shell 121, and then the partition is electrically connected to the main shell 121 or the cover plate of the integrated structure. After a blind hole 150 filled with positive electrode material is provided on at least a part of the surface of the partition facing the pole core, the cover plate of the integrated structure can be connected through a sampling circuit to realize the voltage detection of the positive electrode material filled in the blind hole 150 of the partition.

[0079] For the cover plate including the positive cover plate 141 and the negative cover plate 131, the positive cover plate 141 and the negative cover plate 131 are both welded to the main shell 121, and then the separator is electrically connected to at least one of the main shell 121, the positive cover plate 141 and the negative cover plate 131. After the blind hole 150 filled with positive electrode material is provided on at least a part of the surface of the separator facing the pole core, the sampling circuit can be connected to the negative cover plate 131 through the sampling point to realize the voltage detection of the positive electrode material filled in the blind hole 150 of the separator. Specifically, the separator can be arranged between the second side wall 1212 of the main shell 121 and the pole core 110, and the two ends of the separator are respectively fixedly connected to the positive cover plate 141 and the negative cover plate 131 to wrap the pole core 110 and protect the pole core 110. After the blind hole 150 is provided on at least part of the surface of the separator facing the electrode core, the positive electrode material is filled in the blind hole 150 as the reference electrode of the three electrodes, and the blind hole 150 is covered with a diaphragm to isolate the negative electrode layer and the positive electrode material, so as to realize insulation between the positive electrode material filled in the blind hole 150 and the electrode core 110, and the separator realizes an electron path with at least one of the positive electrode cover plate 141 and the negative electrode cover plate 131, and then a sampling circuit can be arranged on the battery cell 100, and the sampling points on the battery cell 100 are connected through the sampling circuit to realize the detection of the positive and negative electrode potentials of the battery cell 100. Since the change of the voltage of the battery cell 100 is mainly reflected in the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole 150 is very stable, it can accurately reflect the real potential level of the positive and negative electrodes of the battery cell 100, so as to assist in judging the real charge state of the battery cell 100 and whether lithium plating occurs. Moreover, when the shell and the negative electrode are short-circuited or slightly shorted, the positive electrode material filled in the blind hole 150 will be corroded first, thereby protecting the shell, avoiding corrosion and leakage of the shell, and improving the safety of the battery cell 100.

[0080] In some embodiments, the battery cell 100 may be configured as a blade battery cell so that the battery cell 100 has advantages such as high energy density, safety performance, and low temperature performance.

[0081] According to another aspect of the present application, a battery pack is provided, the battery pack including a battery cell.

[0082] The battery cell may be implemented as the battery cell 100 mentioned above, and reference may be made to the above description, which will not be repeated here.

[0083] The number of cells in the battery pack may be one or more, and there is no limitation on this. When there are more than one cell, the cells may be connected in series or in parallel, or some of the cells may be connected in series and the other cells may be connected in parallel.

[0084] In some embodiments, the battery pack further includes a sampling circuit, which is connected to the battery pack to collect the voltage between the negative electrode and the positive electrode material of the battery cell in the battery pack. The specific connection method between the sampling circuit and the battery cell in the battery pack and the specific detection method of the battery cell can be found in the above description and will not be repeated here.

[0085] According to another aspect of the present application, an electrical device is provided. The electrical device includes the electrical device and a battery pack. The battery pack is used to provide electrical energy to the electrical device.

[0086] Among them, the battery pack can be implemented as the battery pack mentioned above, and reference can be made to the introduction above, which will not be repeated here.

[0087] It should be noted that the electrical equipment mentioned above may include vehicles, ships, airplanes, energy storage equipment, etc., without limitation thereto, and electrical appliances may be air conditioners, screens, power systems, etc. in the electrical equipment, without limitation thereto.

[0088] In summary, according to the battery cells, battery packs and electrical equipment of the embodiments of the present application, a blind hole is provided on at least a portion of the inner surface of the shell, a positive electrode material is filled in the blind hole as a reference electrode of the three electrodes, and an electronically insulating and ion-conductive diaphragm is used to cover the blind hole to isolate the electrode core and the positive electrode material. Since the change in the battery cell voltage is mainly reflected in the negative electrode, and the voltage of the reference electrode formed by the positive electrode material filled in the blind hole is very stable, whether the capacity of the battery cell decays in a static state or the capacity of the battery cell changes due to abnormal conditions such as lithium deposition in the battery cell in a dynamic state, the actual charge state of the battery cell can be accurately reflected by the reference electrode formed by the negative electrode of the battery cell and the positive electrode material filled in the blind hole.

[0089] Moreover, since the blind holes of the shell are filled with positive electrode materials, the positive electrode materials filled in the blind holes will be corroded preferentially when the shell and the negative electrode are short-circuited or slightly shorted, thereby protecting the shell, avoiding corrosion and leakage of the shell, and improving the safety of the battery cell.

[0090] Furthermore, the positive electrode material is filled in the blind hole on the inner surface of the battery cell shell and will not occupy other space in the shell, thereby improving the space utilization of the battery cell.

[0091] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application to this. Those of ordinary skill in the art may make various changes and modifications therein without departing from the scope and spirit of the present application. All these changes and modifications are intended to be included within the scope of the present application as required by the appended claims.

[0092] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various application aspects, in the description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present application should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the corresponding claims, the application point is that the corresponding technical problem can be solved with less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are hereby explicitly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0093] In addition, those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0094] It should be noted that the above embodiments illustrate rather than limit the present application, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets should not be construed as a limitation to the claims. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names.

Claims

1. A battery cell, characterized in that: The battery cell comprises: Pole core; A shell, wherein the pole core is arranged in the shell; Wherein, a blind hole is provided on at least a part of the inner surface of the shell, and the blind hole is filled with positive electrode material; The battery core further includes a diaphragm, which is used for electronic insulation and ion conduction. The diaphragm covers the blind hole to isolate the electrode core and the positive electrode material.

2. The battery cell according to claim 1, characterized in that: The battery cell further includes a sampling point, and the sampling point is used to connect a sampling circuit to collect the voltage between the negative electrode of the battery cell and the positive electrode material.

3. The battery cell according to claim 1, characterized in that: The housing comprises a main housing and a cover plate, The main shell is provided with an opening for exposing the pole core, and the cover plate is arranged at the opening to close the opening.

4. The battery cell according to claim 3, characterized in that: The blind hole is arranged on at least a partial area of ​​the inner surface of the main shell.

5. The battery cell according to claim 4, characterized in that: The main housing is a rectangular housing, and the rectangular housing comprises a first side wall and a second side wall connected to each other, and the area of ​​the first side wall is greater than the area of ​​the second side wall; Wherein, the blind hole is provided on at least a portion of the inner surface of the first side wall; and / or The blind hole is arranged on at least a portion of the inner surface of the second side wall.

6. The battery cell according to claim 3, characterized in that: The cover plate is an integral structure, and the blind hole is provided on at least a part of the inner surface of the cover plate of the integral structure; or, The cover plate includes a positive electrode cover plate and a negative electrode cover plate, and the blind hole is arranged on at least a part of the inner surface of the negative electrode cover plate.

7. The battery cell according to claim 6, characterized in that: An explosion-proof valve is arranged on the cover plate of the integrated structure, and the blind hole is arranged close to the explosion-proof valve; or, An explosion-proof valve is arranged on the negative electrode cover plate, and the blind hole is arranged close to the explosion-proof valve.

8. The battery cell according to claim 3, characterized in that: The housing further comprises a partition disposed between the main housing and the pole core, wherein the partition is electrically connected to the main housing or the cover plate. The blind hole is arranged on at least a portion of the surface of the partition facing the pole core.

9. The battery cell according to claim 3, characterized in that: The cover plate is an integrated structure, a negative pole is arranged on the cover plate of the integrated structure, and the battery cell further comprises a sampling point, and the sampling point is used to connect a sampling circuit to collect the voltage between the negative pole and the cover plate; or, The cover plate includes a positive cover plate and a negative cover plate, the negative cover plate is provided with a negative pole, and the battery cell further includes a sampling point, which is used to connect a sampling circuit to collect the voltage between the negative pole and the negative cover plate.

10. The battery cell according to claim 1, characterized in that: The state of charge of the positive electrode material is 30% to 50%.

11. The battery cell according to claim 1, characterized in that: The size of the blind hole is 0.1 mm to 0.2 mm.

12. A battery pack, characterized in that: The battery pack comprises the battery cell according to any one of claims 1 to 11.

13. The battery pack according to claim 12, characterized in that: The battery pack further includes a sampling circuit, which is connected to the battery pack to collect the voltage between the negative electrode and the positive electrode material of the battery cell in the battery pack.

14. An electrical device, characterized in that: The electrical equipment includes an electrical appliance and a battery pack as claimed in claim 12 or 13, and the battery pack is used to provide electrical energy to the electrical appliance.

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