Battery cell, battery, battery pack and electric equipment

Abstract

The utility model relates to a battery cell, a battery, a battery pack and electric equipment, the battery cell comprises a plurality of pole pieces, the plurality of pole pieces comprise a positive pole piece, a negative pole piece and at least one composite pole piece, a diaphragm is arranged between any two adjacent pole pieces, the composite pole piece is arranged between the positive pole piece and the negative pole piece, and the diaphragm is arranged between the positive pole piece and the negative pole piece. A negative active material is arranged on one side, facing the positive pole piece, of the composite pole piece, a positive active material is arranged on one side, facing the negative pole piece, of the composite pole piece, and the positive active material and the negative active material are connected in series. Through the technical scheme, the battery cell provided by the utility model can improve the output voltage of the battery cell, simplify the assembly difficulty of the battery pack and reduce the weight of the battery pack.

Description

Technical Field

[0001] The present disclosure relates to the technical field of battery packs, and in particular, to a battery cell, a battery, a battery pack, and an electrical device using the same. Background Art

[0002] In the related art, in order to achieve a specific rated output voltage, the main method for a battery pack is to connect multiple battery cells in series through connecting pieces. Therefore, the lower the output voltage of a single battery cell, the more battery cells are required. Currently, the output voltage of battery cells is relatively low, resulting in a large number of connecting pieces, which not only increases the assembly difficulty but also increases the weight of the battery pack. Summary of the Utility Model

[0003] An object of the present disclosure is to provide a battery cell, a battery, a battery pack, and an electrical device using the same, which can improve the output voltage of the battery cell itself, simplify the assembly difficulty of the battery pack, and reduce the weight of the battery pack.

[0004] To achieve the above object, the present disclosure provides a battery cell, including a plurality of electrode plates. The plurality of electrode plates include a positive electrode plate, a negative electrode plate, and at least one composite electrode plate. A separator is disposed between any two adjacent electrode plates. The composite electrode plate is disposed between the positive electrode plate and the negative electrode plate. A negative active material is disposed on a side of the composite electrode plate facing the positive electrode plate, and a positive active material is disposed on a side of the composite electrode plate facing the negative electrode plate. The positive active material and the negative active material are connected in series.

[0005] Optionally, the composite electrode plate has a metal sheet. The positive active material and the negative active material are respectively disposed on two sides of the metal sheet and are connected in series through the metal sheet.

[0006] Optionally, the metal sheet includes a first sub-sheet and a second sub-sheet that are bonded together. One of the first sub-sheet and the second sub-sheet is provided with the positive active material, and the other is provided with the negative active material.

[0007] Optionally, the first sub-sheet is made of copper, and the negative active material is disposed on the first sub-sheet; the second sub-sheet is made of aluminum, and the positive active material is disposed on the second sub-sheet.

[0008] Optionally, the thickness of the metal sheet is 1 μm to 600 μm.

[0009] Optionally, the thickness of the first sub-sheet is equal to the thickness of the second sub-sheet.

[0010] Optionally, the positive electrode plate is connected with a positive electrode tab, and the negative electrode plate is connected with a negative electrode tab.

[0011] Based on the above technical solutions, the present disclosure further provides a battery, including the above battery cell.

[0012] Based on the above technical solutions, the present disclosure further provides a battery pack, including the above battery.

[0013] Based on the above technical solutions, the present disclosure further provides an electrical device, including the above battery pack.

[0014] Through the above technical solutions, in the electric core provided by the present disclosure, since a separator is provided between two adjacent electrode plates, for the positive electrode plate and the adjacent composite electrode plate, the positive active material on the positive electrode plate and the negative active material on the composite electrode plate form an independent battery unit through the separator; similarly, for the negative electrode plate and the adjacent composite electrode plate, the negative active material on the negative electrode plate and the positive active material on the composite electrode plate form an independent battery unit through the separator; when there are at least two composite electrode plates, for two adjacent composite electrode plates, the positive active material on one composite electrode plate and the negative active material on the other composite electrode plate form an independent battery unit through the separator; here, in the present disclosure, the positive active material and the negative active material on the composite electrode plate are in series, that is, the above at least two battery units are connected in series. Thus, through the series connection of the above at least two battery units, the output voltage of the electric core can be effectively increased. Among them, the composite electrode plate may not lead out an electrode tab. For a battery using the electric core of the present disclosure, the output voltage of the battery can be increased, and further, the assembly difficulty of the battery pack can be simplified and the weight of the battery pack can be reduced.

[0015] Other features and advantages of the present disclosure will be described in detail in the subsequent specific implementation section. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings are used to provide a further understanding of the present disclosure, and constitute a part of the specification. Together with the following specific implementation, they are used to explain the present disclosure, but do not constitute a limitation to the present disclosure. In the drawings:

[0017] Figure 1 is a schematic structural diagram of an electric core in the related art provided by an embodiment of the present disclosure;

[0018] Figure 2 is an equivalent circuit diagram of an electric core in the related art provided by an embodiment of the present disclosure;

[0019] Figure 3 is a schematic structural diagram of a battery provided by an embodiment of the present disclosure;

[0020] Figure 4 is a schematic structural diagram of an electric core provided by an embodiment of the present disclosure;

[0021] Figure 5 is a schematic structural diagram of a metal sheet provided by an embodiment of the present disclosure;

[0022] Figure 6 It is the equivalent circuit diagram of the battery cell provided by the embodiments of the present disclosure.

[0023] Description of the reference numerals

[0024] 1 - positive electrode tab; 11 - positive electrode ear; 2 - negative electrode tab; 21 - negative electrode ear; 3 - composite tab; 30 - metal sheet; 31 - first segment; 32 - second segment; 33 - positive active material; 34 - negative active material; 4 - separator; 5 - battery cell; 100 - battery unit; 1' - positive electrode tab; 11' - positive electrode ear; 2' - negative electrode tab; 21' - negative electrode ear; 5' - battery cell; 100' - battery unit. Detailed implementation manners

[0025] The following will describe in detail the specific implementation manners of the present disclosure with reference to the accompanying drawings. It should be understood that the specific implementation manners described herein are only used to illustrate and explain the present disclosure, and are not used to limit the present disclosure.

[0026] In the present disclosure, unless otherwise stated, the terms "first", "second", etc. used in the present disclosure are used to distinguish one element from another element, and do not have sequentiality and importance. In addition, in the following description, when referring to the accompanying drawings, unless otherwise explained, the same reference numerals in different drawings represent the same or similar elements. The above definitions are only used to explain and illustrate the present disclosure, and should not be construed as a limitation to the present disclosure.

[0027] In the related art, referring to Figure 1 as shown in, most of the battery cells 5' are stacked or wound in the structure of separator 4' - positive electrode tab 1' - separator 4' - negative electrode tab 2' - separator 4'. Each positive electrode tab 1' and negative electrode tab 2' are respectively provided with a positive electrode ear 11' and a negative electrode ear 21'. A plurality of positive electrode ears 11' are combined to form the positive electrode of the battery cell 5'. Correspondingly, a plurality of negative electrode ears 21' are combined to form the negative electrode of the battery cell 5'. The equivalent circuit diagram of the battery cell 5' is as Figure 2 shown. When the battery cell has a plurality of positive electrode tabs 1', negative electrode tabs 2' and separators 4', each positive electrode tab 1', separator 4' and negative electrode tab 2' form an independent battery unit 100'. Adjacent two battery units 100' are blocked by the separator 4', and electrons cannot pass through this separator 4', that is, adjacent two battery units 100' are in parallel. The output voltage of this battery cell 5' is the output voltage of a single battery unit 100'. In this way, the output voltage of the battery cell 5' is relatively low.

[0028] According to the specific implementation manners provided by the present disclosure, referring to Figures 3 to 6As shown in the figure, a battery cell 5 is provided, which includes a plurality of electrode plates. The plurality of electrode plates include a positive electrode plate 1, a negative electrode plate 2, and at least one composite electrode plate 3. A separator 4 is disposed between any two adjacent electrode plates. The composite electrode plate 3 is disposed between the positive electrode plate 1 and the negative electrode plate 2. A negative active material 34 is disposed on one side of the composite electrode plate 3 facing the positive electrode plate 1, and a positive active material 33 is disposed on the side facing the negative electrode plate 2. The positive active material 33 and the negative active material 34 are connected in series.

[0029] Through the above technical solution, in the battery cell provided in the present disclosure, since a separator 4 is disposed between two adjacent electrode plates, for the positive electrode plate 1 and the adjacent composite electrode plate 3, the positive active material 33 on the positive electrode plate 1 and the negative active material 34 on the composite electrode plate 3 form an independent battery unit 100 through the separator 4; similarly, for the negative electrode plate 2 and the adjacent composite electrode plate 3, the negative active material 34 on the negative electrode plate 2 and the positive active material 33 on the composite electrode plate 3 form an independent battery unit 100 through the separator 4; when there are at least two composite electrode plates 3, for two adjacent composite electrode plates 3, the positive active material 33 on one composite electrode plate 3 and the negative active material 34 on the other composite electrode plate 3 form an independent battery unit 100 through the separator 4; here, in the present disclosure, the positive active material 33 and the negative active material 34 on the composite electrode plate 3 are connected in series, that is to say, the above at least two battery units 100 are connected in series. Thus, through the series connection of the above at least two battery units 100, the output voltage of the battery cell 5 can be effectively increased. Among them, the composite electrode plate 3 may not lead out a tab. For a battery using the battery cell 5 of the present disclosure, the output voltage of the battery can be increased, and then the assembly difficulty of the battery pack can be simplified, and the weight of the battery pack can be reduced. It should be explained here that, as shown in Figure 3 As shown in the figure, the composite electrode plate 3 may also be provided in plurality, and the present disclosure does not make specific limitations thereto. At this time, as shown in Figure 6 As shown in the figure, in an ideal state, a fixed number of composite electrode plates 3 can achieve the output voltage of the battery cell 5 to increase in multiples of this fixed number. However, in actual use, the increase in the number of composite electrode plates 3 also means an increase in battery resistance. Therefore, the output voltage of the battery cell 5 is usually lower than the output voltage that can be achieved under ideal conditions. At the same time, factors such as battery size and electrolyte withstand voltage need to be comprehensively considered. Therefore, the specific number of composite electrode plates 3 can be arbitrarily and appropriately selected according to actual conditions, and the present disclosure also does not make specific limitations thereto.

[0030] In the battery cell 5 provided in the present disclosure, the positive active material 33 and the negative active material 34 can be connected in series in any suitable manner, and the present disclosure does not make specific limitations thereto. As an exemplary embodiment, as shown in Figure 2As shown, the composite electrode 3 may have a metal sheet 30, and the positive electrode active material 33 and the negative electrode active material 34 may be disposed on both sides of the metal sheet 30 respectively to achieve series connection between the positive electrode active material 33 and the negative electrode active material 34. The metal sheet 30 can not only act as a carrier, that is, as a carrier for the positive electrode active material 33 and the negative electrode active material 34, providing an attachment space for charged ions in the electrolyte, but also play a role in connecting the negative electrode active material 34 and the positive electrode active material 33 in series.

[0031] In the battery cell 5 provided by the present disclosure, the metal sheet can be constructed in any suitable form, and the present disclosure does not make specific limitations thereto. As an exemplary embodiment, referring to Figure 2 and Figure 3 as shown, the metal sheet 30 may include a first sheet 31 and a second sheet 32 that are adhered together. One of the first sheet 31 and the second sheet 32 may be provided with the positive electrode active material 33, and the other may be provided with the negative electrode active material 34. The arrangement of the metal sheet 30 including the first sheet 31 and the second sheet 32 can facilitate setting the first sheet 31 and the second sheet 32 as sheets of different materials, and further facilitate the attachment of the positive electrode active material 33 and the negative electrode active material 34 to the corresponding sheets.

[0032] In some other embodiments, the metal sheet 30 may also be constructed as a composite foil with a three-layer sheet structure, that is, it further includes an intermediate sheet, that is, the first sheet 31 and the second sheet 32 are respectively adhered to both sides of the intermediate sheet to reduce the thickness of the first sheet 31 and the second sheet 32 on both sides. This is because the first sheet 31 and the second sheet 32 are usually made of metal, and setting the metal layer as thin as possible can reduce the strength of the first sheet 31 and the second sheet 32. When the battery cell 5 is impacted, it is not easy to pierce the separator 4, thereby reducing the occurrence of short circuit.

[0033] Among them, the first sheet 31 and the second sheet 32 can be adhered and fixed together in any suitable manner, and the present disclosure does not make specific limitations thereto. As an exemplary embodiment, the first sheet 31 and the second sheet 32 can be adhered together by pressing, so as to ensure full contact between the first sheet 31 and the second sheet 32 while fixing the first sheet 31 and the second sheet 32 together, and avoid the problem of increased internal resistance of the battery cell 5 caused by insufficient contact between the first sheet 31 and the second sheet 32.

[0034] In the battery cell 5 provided by the present disclosure, the first segment 31 and the second segment 32 can be made of any suitable metal material, and the present disclosure does not make specific limitations thereto. As an exemplary embodiment, the first segment 31 can be made of copper, and the negative electrode active material 34 can be disposed on the first segment 31; the second segment 32 can be made of aluminum, and the positive electrode active material 33 can be disposed on the second segment 32. Taking a lithium battery as an example, since aluminum will react with lithium metal, and copper is prone to oxidation at high potentials, the positive electrode plate 1 is usually made of aluminum, and the negative electrode plate 2 is made of copper. Correspondingly, the composite electrode plate 3 is usually set as a copper-aluminum composite material, that is, the first segment 31 is a copper sheet, and the second segment 32 is an aluminum sheet.

[0035] In the battery cell 5 provided by the present disclosure, the thickness of the metal sheet can be designed in any suitable manner according to the actual size of the battery cell 5, and the present disclosure does not make specific limitations thereto. As an exemplary embodiment, the thickness of the metal sheet can be 1 μm to 600 μm. The thickness of the metal sheet should be as small as possible while ensuring that it can provide sufficient attachment vacancies for the ions in the electrolyte, so as to reduce the size and weight of the battery cell 5 and further improve the energy density of the battery cell 5.

[0036] Among them, the thickness of the first segment 31 relative to the thickness of the second segment 32 can also be designed in any suitable manner according to the actual size of the battery cell 5, and the present disclosure does not make specific limitations thereto. As an exemplary embodiment, the thickness of the first segment 31 can be equal to the thickness of the second segment 32. In some other embodiments, the thicknesses of the first segment 31 and the second segment 32 can also be constructed to be any suitable thickness according to the different materials constituting themselves, and the present disclosure does not make specific limitations thereto.

[0037] In the battery cell 5 provided by the present disclosure, as an exemplary embodiment, a separator 4 is provided between the composite electrode plate 3 and the positive electrode plate 1, between the composite electrode plate 3 and the negative electrode plate 2, and between the composite electrode plates 3, so as to separate each electrode plate to prevent battery short circuit while not interrupting the ion transmission in the electrolyte. Among them, a positive electrode tab 11 and a negative electrode tab 21 are respectively connected to the positive electrode plate 1 and the negative electrode plate 2, and the positive electrode tab 11 and the negative electrode tab 21 are electrically connected through an external wire.

[0038] On the basis of the above technical solution, the present disclosure further provides a battery, including the above-described battery cell 5, which has all the technical features of the above battery cell 5, so it will not be elaborated herein. Since the battery cell 5 provided by the present disclosure has a relatively high output voltage, it can meet the rated output voltage requirement of the battery by connecting in series with a smaller number, and correspondingly reduces the number of connecting pieces for connecting each battery cell 5 in the traditional battery. In this way, on the one hand, the assembly steps of the battery are simplified; on the other hand, since the connecting piece itself has a certain internal resistance, the reduction of the number of connecting pieces also reduces the internal resistance of the battery and improves the energy utilization rate of the battery.

[0039] On the basis of the above technical solution, the present disclosure further provides a battery pack, including the above-described battery cell 5 or the above-described battery. The battery cell 5 has all the technical features of the above battery cell 5, and the battery has all the technical features of the above battery, so it will not be elaborated herein.

[0040] On the basis of the above technical solution, the present disclosure further provides an electrical device, including at least one of the above-described battery cell 5, the above-described battery, and the above-described battery pack. The battery cell 5 has all the technical features of the above battery cell 5, the battery has all the technical features of the above battery, and the battery pack has all the technical features of the above battery pack, so it will not be elaborated herein. Among them, the electrical device can be any suitable device such as a vehicle, an energy storage cabinet, an aircraft, etc., and the present disclosure does not make specific limitations thereto.

[0041] The preferred embodiments of the present disclosure have been described in detail above with reference to the accompanying drawings. However, the present disclosure is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present disclosure, various simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0042] In addition, it should be noted that, in the case of no contradiction, the various specific technical features described in the above specific embodiments can be combined in any suitable manner. To avoid unnecessary repetition, the present disclosure will not separately describe various possible combination manners.

[0043] In addition, any combination can be made between various different embodiments of the present disclosure as long as it does not violate the idea of the present disclosure, and it should also be regarded as the content disclosed by the present disclosure.

Claims

1. A battery cell, characterized in that: It comprises a plurality of pole sheets, the plurality of pole sheets comprise a positive pole sheet, a negative pole sheet and at least one composite pole sheet, a diaphragm is arranged between any two adjacent pole sheets, the composite pole sheet is arranged between the positive pole sheet and the negative pole sheet, a negative electrode active material is arranged on the side of the composite pole sheet facing the positive pole sheet, a positive electrode active material is arranged on the side facing the negative pole sheet, and the positive electrode active material is connected in series with the negative electrode active material.

2. The battery cell according to claim 1, characterized in that: The composite electrode sheet comprises a metal sheet, and the positive electrode active material and the negative electrode active material are arranged on both sides of the metal sheet and are connected in series through the metal sheet.

3. The battery cell according to claim 2, characterized in that: The metal sheet includes a first sheet and a second sheet that are bonded together, one of the first sheet and the second sheet is provided with the positive electrode active material, and the other of the first sheet and the second sheet is provided with the negative electrode active material.

4. The battery cell according to claim 3, characterized in that: The first segment is made of copper, and the negative electrode active material is arranged on the first segment; the second segment is made of aluminum, and the positive electrode active material is arranged on the second segment.

5. The battery cell according to claim 2, characterized in that: The thickness of the metal sheet is 1 μm to 600 μm.

6. The battery cell according to claim 3, characterized in that: The thickness of the first slice is equal to the thickness of the second slice.

7. The battery cell according to claim 1, characterized in that: The positive electrode plate is connected to a positive electrode tab, and the negative electrode plate is connected to a negative electrode tab.

8. A battery, characterized in that: Comprising a battery cell according to any one of claims 1 to 7.

9. A battery pack, characterized in that: Comprising the battery as claimed in claim 8.

10. An electrical device, characterized in that: A battery pack comprising the battery pack of claim 9.

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