Sodium ion battery cell and battery pack

Abstract

The utility model discloses a sodium-ion battery monomer and a battery pack, the sodium-ion battery monomer comprises a shell, a battery pack, a first battery pack, a second battery pack, a first battery pack, a second battery pack and a second battery pack, and the shell is internally provided with a first cavity and a second cavity; the first pole group is arranged in the first cavity, and the first pole group is provided with a first positive tab and a first negative tab; the second pole group is arranged in the second cavity, the second pole group is provided with a second positive tab and a second negative tab, and the first positive tab is electrically connected with the second negative tab; the first negative tab is connected with the first connecting sheet; and the second positive lug is connected with the second connecting piece. According to the sodium ion battery monomer disclosed by the utility model, the two pole groups are arranged in the shell and are respectively arranged in the first cavity and the second cavity which are independent, so that the voltage of the battery monomer is improved, the production cost of the battery monomer is reduced, the volume energy density of the battery monomer is increased, and the rate capability and the cycling stability of the battery monomer are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery manufacturing, in particular to a sodium ion battery monomer and a battery pack. Background Art

[0002] The relevant technology points out that lithium-ion batteries are currently widely used in power and energy storage due to their relatively mature technology. However, since the positive and negative current collectors are made of aluminum foil and copper foil respectively, considering the cell process yield and cost, the pole rolls or pole groups in the same battery can only be connected in parallel, so the voltage of lithium-ion batteries is basically 3.7V (ternary system) or 3.2V (lithium iron phosphate). In the past two years, the research on sodium-ion batteries has become increasingly popular, and its structural design still uses the design of lithium-ion batteries. First, it cannot highlight its low-cost advantage. Second, the new system battery can develop new components to match the expectations. Utility Model Content

[0003] The utility model aims to solve at least one of the technical problems existing in the prior art. To this end, the utility model proposes a sodium ion battery monomer, which has low production cost and high volume energy density.

[0004] The utility model also provides a battery pack having the sodium ion battery monomer.

[0005] According to the first aspect of the utility model, the sodium ion battery cell comprises: a shell, a first cavity and a second cavity are formed in the shell; a first pole group, the first pole group is arranged in the first cavity, the first pole group has a first positive pole ear and a first negative pole ear; a second pole group, the second pole group is arranged in the second cavity, the second pole group has a second positive pole ear and a second negative pole ear, the first positive pole ear is electrically connected to the second negative pole ear; a first connecting piece, the first negative pole ear is connected to the first connecting piece; a second connecting piece, the second positive pole ear is connected to the second connecting piece.

[0006] According to the sodium ion battery cell of the utility model, by arranging two electrode groups in the shell and respectively arranging them in the independent first cavity and the second cavity, the voltage of the battery cell is increased, the production cost of the battery cell is reduced, the volume energy density of the battery cell is increased, and the rate performance and cycle stability of the battery cell are improved.

[0007] In some embodiments, the first positive electrode tab is connected to the second negative electrode tab by welding, and / or the first negative electrode tab is connected to the first connecting piece by welding, and / or the second positive electrode tab is connected to the second connecting piece by welding.

[0008] In some embodiments, the sodium ion battery cell further includes: an insulating member, wherein the insulating member is disposed at each welding position.

[0009] In some embodiments, the sodium ion battery cell further includes: a cover plate connected to the first connecting plate and the second connecting plate.

[0010] In some embodiments, at least one injection hole is formed on the cover plate, and at least one of the injection holes penetrates the cover plate in the thickness direction of the cover plate. The sodium ion battery cell also includes: an explosion-proof valve, a through hole is formed on the cover plate, and the explosion-proof valve is arranged at the position of the through hole and adjacent to the injection hole.

[0011] In some embodiments, a groove is formed on the cover plate, and the groove extends along the length direction of the cover plate.

[0012] In some embodiments, the sodium ion battery cell further includes: a seal, wherein the seal is disposed in the groove.

[0013] In some embodiments, a partition is disposed in the shell, and the first cavity and the second cavity are formed on both sides of the partition.

[0014] In some embodiments, the first connecting piece and the second connecting piece are both formed as aluminum parts.

[0015] The battery pack according to the second aspect of the utility model comprises a plurality of sodium ion battery cells according to the first aspect of the utility model.

[0016] According to the battery pack of the utility model, by providing the sodium ion battery monomer of the first aspect, the production cost of the battery pack is reduced, the volume energy density of the battery pack is increased, and the rate performance and cycle stability of the battery pack are improved.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the connection of the tabs of a sodium ion battery cell according to an embodiment of the utility model;

[0019] Figure 2 yes Figure 1 A schematic diagram of a side view of the pole group shown in;

[0020] Figure 3 yes Figure 1 Schematic diagram of the connection between the cover plate and the tab of the sodium ion battery cell shown in ;

[0021] Figure 4 is a schematic diagram of the shell of a sodium ion battery cell;

[0022] Figure 5It is a schematic diagram of the assembly of a sodium-ion battery cell;

[0023] Figure 6 yes Figure 5 A schematic diagram of a top view of a sodium ion battery cell shown in ;

[0024] Figure 7 yes Figure 5 Schematic diagram of a side view of a sodium-ion battery cell shown in FIG.

[0025] Reference numerals:

[0026] 100. Sodium ion battery monomer;

[0027] 1. first electrode group; 11. first positive electrode ear; 12. first negative electrode ear;

[0028] 2. second electrode group; 21. second positive electrode ear; 22. second negative electrode ear;

[0029] 3. First connecting piece; 4. Second connecting piece;

[0030] 5. Shell; 51. First cavity; 52. Second cavity; 53. Partition;

[0031] 6. Insulation parts;

[0032] 7. Cover plate; 71. Pole; 72. Liquid injection hole; 73. Groove;

[0033] 8. Explosion-proof valve. DETAILED DESCRIPTION

[0034] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0035] Reference below Figure 1 and Figure 2 A sodium ion battery cell 100 according to an embodiment of the first aspect of the present invention is described.

[0036] like Figure 1 As shown, the sodium ion battery cell 100 according to the first embodiment of the utility model includes: a housing 5, a first pole group 1, a second pole group 2, a first connecting plate 3 and a second connecting plate 4.

[0037] Specifically, a first cavity 51 and a second cavity 52 are formed in the housing 5, the first pole group 1 is disposed in the first cavity 51, the first pole group 1 has a first positive pole ear 11 and a first negative pole ear 12, the second pole group 2 is disposed in the second cavity 52, the second pole group 2 has a second positive pole ear 21 and a second negative pole ear 22, the first positive pole ear 11 is electrically connected to the second negative pole ear 22, the first negative pole ear 12 is connected to the first connecting piece 3, and the second positive pole ear 21 is connected to the second connecting piece 4. Thus, the internal structure of the sodium ion battery cell 100 is cleverly designed and easy to produce.

[0038] According to the sodium ion battery cell 100 of the embodiment of the utility model, by arranging two electrode groups in the shell 5 and respectively arranging them in the independent first cavity 51 and the second cavity 52, the voltage of the battery cell is increased, the production cost of the battery cell is reduced, the volume energy density of the battery cell is increased, and the rate performance and cycle stability of the battery cell are improved.

[0039] In some embodiments of the present invention, the first positive electrode ear 11 is welded to the second negative electrode ear 22, and / or the first negative electrode ear 12 is welded to the first connecting piece 3, and / or the second positive electrode ear 21 is welded to the second connecting piece 4. Preferably, the first positive electrode ear 11 is welded to the second negative electrode ear 22 by ultrasonic welding or laser welding, the first negative electrode ear 12 is welded to the first connecting piece 3 by ultrasonic welding or laser welding, and the second positive electrode ear 21 is welded to the second connecting piece 4 by ultrasonic welding or laser welding. As a result, the welding method is simple and the connection is stable.

[0040] In some embodiments of the present invention, the sodium ion battery cell 100 further includes: an insulating member 6, which is provided at each welding position, and the insulating member 6 has good high temperature resistance. Specifically, the insulating member 6 is provided at the welding position between the first positive electrode ear 11 and the second negative electrode ear 22, the insulating member 6 is provided at the welding position between the first negative electrode ear 12 and the first connecting piece 3, and the insulating member 6 is provided at the welding position between the second positive electrode ear 21 and the second connecting piece 4. Preferably, the insulating member 6 is a high temperature resistant insulating tape.

[0041] In some embodiments of the present invention, the sodium ion battery cell 100 further includes: a cover plate 7, which is connected to the first connecting piece 3 and the second connecting piece 4. Specifically, two poles 71 are formed on the cover plate 7, and the two poles 71 are both located on one side of the length direction of the cover plate 7, the first connecting piece 3 is connected to one pole 71, and the second connecting piece 4 is connected to the other pole 71. As a result, the structure of the sodium ion battery cell 100 is simple, and the connection method is easy to assemble, which reduces the difficulty of assembling the sodium ion battery cell 100 and improves the production efficiency of the sodium ion battery cell 100.

[0042] In some embodiments of the utility model, at least one injection hole 72 is formed on the cover plate 7, and at least one injection hole 72 penetrates the cover plate 7 in the thickness direction of the cover plate 7. The sodium ion battery cell 100 further includes: an explosion-proof valve 8, a through hole is formed on the cover plate 7, and the explosion-proof valve 8 is arranged at the position of the through hole and adjacent to the injection hole 72. As shown in the figure, two injection holes 72 are formed on the cover plate 7, and the two injection holes 72 are arranged at intervals on both sides of the groove 73. Therefore, the design of the cover plate 7 is ingenious, which ensures the safety performance of the first pole group 1 and the second pole group 2 and simplifies the assembly steps of the battery cell.

[0043] In some embodiments of the present invention, as shown in the figure, a groove 73 is formed on the cover plate 7, and the groove 73 extends along the length direction of the cover plate 7. Therefore, the groove 73 is used to avoid the partition 53, ensuring the sealing effect of the first cavity 51 and the second cavity 52 of the battery cell, and avoiding the risk of leakage inside the battery cell.

[0044] In some embodiments of the present invention, the sodium ion battery cell 100 further includes: a seal, which is disposed in the groove 73. Thus, the sealing effect of the first cavity 51 and the second cavity 52 of the battery cell is further guaranteed, the risk of internal leakage of the battery cell is further avoided, and the first cavity 51 and the second cavity 52 can be completely separated.

[0045] In some embodiments of the utility model, a partition 53 is provided in the housing 5, and the first cavity 51 and the second cavity 52 are formed on both sides of the partition 53. That is, the first cavity 51 and the second cavity 52 are separated by the partition 53, and the housing 5 has a simple structure and an ingenious design, which increases the voltage of the battery cell and reduces the space volume of the battery cell.

[0046] Since, if aluminum is used for the negative electrode tab in a lithium-ion battery cell, lithium ions will be embedded in the aluminum foil to form a very brittle powder lithium-aluminum alloy, the negative electrode collector of the lithium-ion battery is generally made of copper foil, but sodium ions will not undergo this reaction, so the negative electrode collector of the sodium-ion battery can be made of aluminum foil. Therefore, the first connecting piece 3 and the second connecting piece 4 are both formed as aluminum parts, reducing the production cost of the sodium-ion battery cell 100.

[0047] The following will refer to Figure 1-Figure 3 The assembly steps of a sodium ion battery cell 100 according to a specific embodiment of the present invention are described.

[0048] Specifically, 1) the first positive electrode ear 11 and the second negative electrode ear 22 are welded and connected by ultrasonic welding or laser welding; 2) high temperature resistant insulating tape is applied to the welding point; 3) the first negative electrode ear 12 is welded and connected to the first connecting piece 3, and the second positive electrode ear 21 is welded and connected to the second connecting piece 4; 4) high temperature resistant insulating tape is applied to the welding point; 5) the connecting piece and the pole 71 of the cover plate 7 are welded together; 6) high temperature resistant insulating tape is applied to the welding point; 7) the first pole group 1 and the second pole group 2 are respectively inserted into the first cavity 51 and the second cavity 52 of the shell 5; 8) the cover plate 7 and the shell 5 are welded and sealed at the periphery; 9) the first cavity 51 and the second cavity 52 of the shell 5 are injected with liquid at the same time through the two injection holes 72 on the cover plate 7.

[0049] The battery pack according to the second embodiment of the present invention includes a plurality of sodium ion battery cells 100 according to the first embodiment of the present invention.

[0050] According to the battery pack of the embodiment of the utility model, by providing the sodium ion battery cell 100 of the first embodiment, the production cost of the battery pack is reduced, the volume energy density of the battery pack is increased, and the rate performance and cycle stability of the battery pack are improved.

[0051] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0052] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0053] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0054] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0055] Although the embodiments of the present invention have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A sodium ion battery cell, characterized in that: include: A housing, wherein a first cavity and a second cavity are formed in the housing; A first pole group, the first pole group is disposed in the first cavity, and the first pole group has a first positive pole ear and a first negative pole ear; A second electrode group, the second electrode group is disposed in the second cavity, the second electrode group has a second positive electrode ear and a second negative electrode ear, and the first positive electrode ear is electrically connected to the second negative electrode ear; a first connecting piece, the first negative electrode ear being connected to the first connecting piece; A second connecting piece, the second positive electrode tab is connected to the second connecting piece.

2. The sodium ion battery cell according to claim 1, characterized in that: The first positive electrode tab is connected to the second negative electrode tab by welding, and / or the first negative electrode tab is connected to the first connecting piece by welding, and / or the second positive electrode tab is connected to the second connecting piece by welding.

3. The sodium ion battery cell according to claim 2, characterized in that: Also includes: An insulating member is provided at each welding position.

4. The sodium ion battery cell according to claim 1, characterized in that: Also includes: A cover plate is connected to the first connecting piece and the second connecting piece.

5. The sodium ion battery cell according to claim 4, characterized in that: At least one injection hole is formed on the cover plate, and at least one of the injection holes penetrates the cover plate in the thickness direction of the cover plate. The battery cell also includes: an explosion-proof valve. A through hole is formed on the cover plate, and the explosion-proof valve is arranged at the position of the through hole and adjacent to the injection hole.

6. The sodium ion battery cell according to claim 5, characterized in that: A groove is formed on the cover plate, and the groove extends along the length direction of the cover plate.

7. The sodium ion battery cell according to claim 6, characterized in that: Also includes: A sealing member is disposed in the groove.

8. The sodium ion battery cell according to any one of claims 1 to 7, characterized in that: A partition is arranged in the shell, and the first cavity and the second cavity are formed on both sides of the partition.

9. The sodium ion battery cell according to any one of claims 1 to 7, characterized in that: The first connecting piece and the second connecting piece are both formed as aluminum parts.

10. A battery pack, characterized in that: The invention comprises a plurality of sodium ion battery cells according to any one of claims 1 to 9.

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