Sodium ion battery

Abstract

The utility model discloses a sodium-ion battery, which comprises a shell, a battery module, a battery module, a battery module, a battery module and a battery module, the plurality of pole groups are arranged in the cavity and are arranged along the width direction of the pole groups, each pole group is provided with a current collector and a pole lug, the current collector and the pole lug are connected and are aluminum pieces, the pole lug comprises a positive pole lug and a negative pole lug, and the positive pole lug of one pole group is directly connected with the negative pole lug or the positive pole lug of another pole group. According to the sodium ion battery disclosed by the utility model, the current collector and the tabs are aluminum pieces, so that the stability of the current collector can be improved, the cost of the pole group is reduced, the production cost of the sodium ion battery is reduced, and the transportation safety is improved. The tabs comprise the positive tab and the negative tab, and the positive tab of one pole group is directly connected with the negative tab or the positive tab of the other pole group without being lapped through a connecting sheet, so that the tab tearing can be avoided, the process yield is improved, the number of parts of the sodium ion battery is reduced, and the assembly process is simplified.

Description

Technical Field

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

[0002] At present, lithium-ion batteries are widely used in power and energy storage due to their 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 follows the design of lithium-ion batteries, which cannot highlight its cost and technical advantages. 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, which can reduce the cost of the electrode group, reduce the production cost, improve the safety of transportation, improve the process yield, and simplify the assembly process.

[0004] The sodium ion battery according to an embodiment of the utility model includes: a shell, a cavity is defined in the shell; a plurality of pole groups, the plurality of pole groups are arranged in the cavity and along the width direction of the pole group, each of the pole groups has a current collector and a pole ear, the current collector and the pole ear are connected and are aluminum parts, the pole ears include positive pole ears and negative pole ears, the positive pole ear of one pole group is directly connected to the negative pole ear or the positive pole ear of another pole group.

[0005] According to the sodium ion battery of the embodiment of the utility model, multiple pole groups are arranged in the cavity of the shell and arranged along the width direction of the pole group, each pole group has a current collector and a pole ear, the current collector and the pole ear are connected and are aluminum parts, which can improve the stability of the current collector, reduce the cost of the pole group, reduce the production cost of the sodium ion battery, and improve the safety of transportation. And the pole ear includes a positive pole ear and a negative pole ear, the positive pole ear of one pole group is directly connected to the negative pole ear or the positive pole ear of another pole group, without the need to overlap through a connecting sheet, which can abolish the ultrasonic welding between the pole groups in the prior art, avoid the tearing of the pole ear, improve the process yield, reduce the number of parts of the sodium ion battery, and simplify the assembly process of the sodium ion battery.

[0006] In addition, the sodium ion battery according to the utility model may also have the following additional technical features:

[0007] In some embodiments, the positive electrode tab of one of two adjacent electrode groups is thermally melt-connected to the negative electrode tab or the positive electrode tab of the other electrode group.

[0008] In some embodiments, a plurality of said pole groups are connected in series.

[0009] In some embodiments, the shell includes: a body, the cavity is disposed on the body, and an opening is provided on one side of the cavity; a cover body, the cover body is covered at the opening, and the tab is located at one end of the cavity facing the cover body.

[0010] In some embodiments, a block is provided in the cavity, and the block extends along the length direction of the pole group to separate the cavity into a plurality of sub-cavities, and the plurality of pole groups are respectively located in the plurality of sub-cavities.

[0011] In some embodiments, the positive electrode ear and the negative electrode ear both include: a main body and a connecting portion, one end of the main body is connected to the connecting portion, and the other end is connected to the current collector, the connecting portions of the two connected electrode ears extend in a direction close to each other, and the connecting portion is located on the side of the block facing the cover body.

[0012] In some embodiments, a groove cooperating with the block is provided on a side of the cover body facing the cavity, and at least a portion of the connecting portion is located in the groove.

[0013] In some embodiments, one end of the block facing the cover body is located in the groove, and the block is adhesively connected to the cover body.

[0014] In some embodiments, the cover body is provided with injection holes, and the injection holes are multiple and correspond one to one with the electrode groups.

[0015] In some embodiments, an explosion-proof valve is disposed on the cover body, and the explosion-proof valve is arranged opposite to the cavity.

[0016] 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

[0017] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0018] Figure 1 is a schematic front view of an electrode group of a sodium ion battery according to an embodiment of the utility model;

[0019] Figure 2 It is a schematic diagram of the cooperation between the electrode group and the hot melt device of the sodium ion battery according to the embodiment of the utility model;

[0020] Figure 3is a schematic top view of a pole group of a sodium ion battery according to an embodiment of the utility model;

[0021] Figure 4 is a bottom view of a cover of a sodium ion battery according to an embodiment of the utility model;

[0022] Figure 5 is a top view of the body of the sodium ion battery according to an embodiment of the utility model;

[0023] Figure 6 is a top view of a sodium ion battery according to an embodiment of the utility model;

[0024] Figure 7 is a right side schematic diagram of a sodium ion battery according to an embodiment of the utility model;

[0025] Figure 8 It is a front schematic diagram of a sodium ion battery according to an embodiment of the utility model.

[0026] Reference numerals:

[0027] 100. Sodium ion battery;

[0028] 1. Shell; 11. Main body; 111. Cavity; 112. Block; 113. Sub-cavity; 12. Cover; 121. Groove; 122. Liquid injection hole; 123. Explosion-proof valve; 13. Positive pole; 14. Negative pole;

[0029] 2. Pole group; 20. Pole ear; 21. Positive electrode ear; 22. Negative electrode ear; 23. Main body; 24. Connecting part;

[0030] 200. Hot melt device;

[0031] 3. Main body; 31. Heating chamber; 32. Ribs. DETAILED DESCRIPTION

[0032] 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 only used to explain the present invention, and cannot be understood as limiting the present invention.

[0033] 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.

[0034] 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.

[0035] 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.

[0036] The sodium ion battery 100 according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0037] like Figure 1 , Figure 7 and Figure 8 As shown, the sodium ion battery 100 according to an embodiment of the present invention includes a housing 1 and a plurality of electrode groups 2 .

[0038] Specifically, refer to the attached Figure 1 and attached Figure 5 As shown, a cavity 111 is defined in the housing 1, and a plurality of pole groups 2 are arranged in the cavity 111 and along the width direction of the pole group 2 (see attached Figure 1 The housing 1 can protect the plurality of pole groups 2 to prevent the pole groups 2 from being exposed and damaged. For example, the pole groups 2 can be two, three, four, five or six. In a specific example, refer to the attached Figure 1As shown, there are four electrode groups 2 arranged along the width direction of the electrode group 2, which can ensure the power storage capacity of the sodium ion battery 100.

[0039] Further, each electrode group 2 has a current collector and a pole ear 20, and the current collector and the pole ear 20 are connected and are both aluminum parts. The current collector of each electrode group 2 includes a positive electrode current collector and a negative electrode current collector. It should be noted that in the prior art, the positive electrode current collector of the lithium ion battery adopts aluminum foil, and the negative electrode current collector generally adopts copper foil. If the negative electrode current collector adopts the same aluminum foil as the positive electrode current collector, it is easy to cause lithium ions to be embedded in the negative electrode current collector to form a very brittle powder lithium aluminum alloy during the charging process of the lithium ion battery. However, the utility model is a sodium ion battery 100, and sodium ions will not react with aluminum. Therefore, the negative electrode current collector can use the same aluminum foil as the positive electrode current collector, thereby reducing the cost of the electrode group 2, and then reducing the production cost of the sodium ion battery 100. In addition, the sodium ion battery 100 uses aluminum foil with better stability as the negative electrode current collector, which can be fully discharged to 0V before transportation, which can improve the safety of transportation.

[0040] Further, see Appendix Figure 3 As shown, the pole ear 20 includes a positive pole ear 21 and a negative pole ear 22, and the positive pole ear 21 of one pole group 2 is directly connected to the negative pole ear 22 or the positive pole ear 21 of another pole group 2. It can be understood that because the positive pole ear 21 and the negative pole ear 22 are both aluminum parts, the positive pole ear 21 and the negative pole ear 22 are made of the same material, so the positive pole ear 21 of one pole group 2 can be directly connected to the negative pole ear 22 or the positive pole ear 21 of another pole group 2, without the need to overlap through the connecting sheet, which can eliminate the ultrasonic welding between the pole groups in the prior art, avoid the tearing of the pole ear 20, improve the process yield, reduce the number of parts of the sodium ion battery 100, and simplify the assembly process of the sodium ion battery 100. It can be understood that the positive pole ear 21 of one pole group 2 can be directly connected to the negative pole ear 22 of another pole group 2, or it can be directly connected to the positive pole ear 21 of another pole group 2.

[0041] In some embodiments, the sodium ion battery 100 is a layered oxide system, the voltage of the sodium ion battery 100 is V1, the number of electrode groups 2 is N, the average voltage of the plurality of electrode groups 2 is 3V, and satisfies: V1=3*N, and the number of electrode groups 2 can be adjusted according to user needs, thereby adjusting the voltage V1 of the sodium ion battery 100, so as to meet more application scenarios.

[0042] It should be noted that, since sodium is a more common element than lithium, the cost of the sodium ion battery 100 of the present invention is relatively low compared to the lithium ion battery of the prior art.

[0043] According to the sodium ion battery 100 of the embodiment of the utility model, a plurality of pole groups 2 are arranged in the cavity 111 of the housing 1 and arranged along the width direction of the pole group 2, each pole group 2 has a current collector and a pole ear 20, the current collector and the pole ear 20 are connected and are both aluminum parts, which can improve the stability of the current collector, reduce the cost of the pole group 2, reduce the production cost of the sodium ion battery 100, and improve the safety of transportation. And the pole ear 20 includes a positive pole ear 21 and a negative pole ear 22, the positive pole ear 21 of one pole group 2 is directly connected to the negative pole ear 22 or the positive pole ear 21 of another pole group 2, without overlapping through a connecting sheet, which can abolish the ultrasonic welding between the pole groups in the prior art, avoid the tearing of the pole ear 20, improve the process yield, reduce the number of parts of the sodium ion battery 100, and simplify the assembly process of the sodium ion battery 100.

[0044] In some embodiments of the present invention, refer to the attached Figure 3 As shown, the positive electrode ear 21 of one of the two adjacent electrode groups 2 is connected to the negative electrode ear 22 or the positive electrode ear 21 of the other electrode group by heat melting. The positive electrode ear 21 of one of the two adjacent electrode groups 2 is connected to the negative electrode ear 22 or the positive electrode ear 21 of the other electrode group by heat melting, which is not easy to corrode and has a long service life. It can reduce the assembly difficulty of the sodium ion battery 100, simplify the assembly process of the sodium ion battery 100, improve the reliability and stability of the sodium ion battery 100, and extend the service life of the sodium ion battery 100. It can be understood that the positive electrode ear 21 of one electrode group 2 can be connected to the negative electrode ear 22 of the other electrode group 2 by heat melting, or it can be connected to the positive electrode ear 21 of the other electrode group 2 by heat melting.

[0045] Specifically, refer to the attached Figure 2 As shown, the hot melting of the tab 20 is achieved by a hot melting device 200, which includes a main body 3 and a heating element. The main body 3 has a heating chamber 31, in which aluminum water is arranged, and the upper end of the heating chamber 31 is open for the tab 20 to be immersed in the aluminum water. The heating element is arranged in the main body 3 to heat the aluminum water in the heating chamber 31, so that the aluminum water always remains in a liquid state. Since the tab 20 is an aluminum part, after the aluminum water penetrates into the interlayer of the tab 20, the tab 20 is squeezed and then cooled to achieve the hot melting of the positive tab 21 of one of the two adjacent pole groups 2 and the negative tab 22 or the positive tab 21 of the other. It should be noted that after the plurality of pole groups 2 are arranged, the plurality of pole groups 2 are inverted so that the tab 20 can be extended into the aluminum water for 1s, and the tab 20 is taken out from the aluminum water after hot melting, and the two tabs 20 to be connected are squeezed together, and the connection is achieved after cooling.

[0046] Further, see Attachment Figure 2 As shown, a plurality of ribs 32 are provided in the heating chamber 31. The ribs 32 extend along the length direction of the electrode group 2 (see the attached Figure 3 The arrangement direction of the plurality of ribs 32 (see the attached Figure 2 a direction shown in the figure) and the arrangement direction of the pole group 2 (see the attached Figure 2 The ribs 32 are arranged to strengthen the structure and improve the structural strength of the hot melt device 200.

[0047] In some embodiments of the present invention, refer to the attached Figure 3 As shown, multiple electrode groups 2 are connected in series. Specifically, the shell 1 has a positive electrode column 13 and a negative electrode column 14, and the positive electrode column 13 and the negative electrode column 14 are arranged at intervals. The positive electrode ear 21 of one electrode group 2 is hot-melt connected to the negative electrode ear 22 of the electrode group 2 on the adjacent side or laser welded to the positive electrode column 13, and the negative electrode ear 22 is hot-melt connected to the positive electrode ear 21 of the electrode group 2 on the other adjacent side or laser welded to the negative electrode column 14, so as to realize the connection of multiple electrode groups 2 and realize a complete circuit.

[0048] Of course, the present invention is not limited thereto, and multiple electrode groups 2 may also be connected in parallel, with the positive electrode ear 21 of one electrode group 2 connected to the positive electrode ear 21 of another electrode group 2 , and the negative electrode ear 22 connected to the negative electrode ear 22 of another electrode group 2 .

[0049] In some embodiments of the present invention, refer to the attached Figure 4 and attached Figure 5 As shown, the shell 1 includes a body 11 and a cover 12, a cavity 111 is provided on the body 11, a plurality of electrode groups 2 are provided in the cavity 111, an opening is provided on one side of the cavity 111 for the electrode group 2 to be placed in the cavity 111, the cover 12 is covered at the opening and welded and sealed with the periphery of the body 11, and the pole ear 20 is located at one end of the cavity 111 facing the cover 12, which can facilitate the placement of the electrode group 2 in the cavity 111, and then the cover 12 is covered at the opening, thereby reducing the difficulty of assembling the sodium ion battery 100.

[0050] In a further embodiment of the present invention, refer to the attached Figure 5 As shown, a block 112 is provided in the cavity 111, and the block 112 extends along the length direction of the pole group 2 to divide the cavity 111 into a plurality of sub-cavities 113. The plurality of pole groups 2 are respectively located in the plurality of sub-cavities 113. The setting of the block 112 can play a positioning and limiting role for the plurality of pole groups 2, and is convenient for respectively loading the plurality of pole groups 2 into the plurality of sub-cavities 113, and can set the plurality of pole groups 2 at intervals, and can also strengthen the structural strength of the shell 1 to a certain extent. It can be understood that the block 112 can be one or a plurality of blocks 112 spaced along the width direction of the pole group 2. For example, when there is one block 112, the cavity 111 can be divided into two sub-cavities 113, when there are two blocks 112, the cavity 111 can be divided into three sub-cavities 113, and when there are three blocks 112, the cavity 111 can be divided into four sub-cavities 113. In a specific example, refer to the attached Figure 1 and attached Figure 5 As shown, there are four pole groups 2 arranged along the width direction of the pole group 2 , and there are three barriers 112 to divide the cavity 111 into four sub-cavities 113 . The four pole groups 2 correspond to the four sub-cavities 113 one by one.

[0051] In a further embodiment of the present invention, refer to the attached Figure 2 and attached Figure 3 As shown, the positive electrode ear 21 and the negative electrode ear 22 each include a main body 23 and a connecting portion 24, one end of the main body 23 is connected to the connecting portion 24, and the other end is connected to the current collector, the connecting portions 24 of the two connected electrode ears 20 extend in a direction close to each other, and the connecting portion 24 is located on the side of the block 112 facing the cover body 12. After the multiple electrode groups 2 are connected, the multiple electrode groups 2 are placed in the multiple sub-cavities 113 at the same time, and the connecting portion 24 is located on the side of the block 112 facing the cover body 12, which will not affect the normal placement of the electrode group 2 into the cavity 111, avoid interference, and ensure the assembly of the sodium ion battery 100.

[0052] In a further embodiment of the present invention, refer to the attached Figure 4 As shown in the attached reference Figure 5 A groove 121 cooperating with the block 112 is provided on one side of the cover 12 facing the cavity 111. There are a plurality of blocks 112 spaced apart along the width direction of the pole group 2. There are a plurality of grooves 121 corresponding one to one with the blocks 112. At least part of the connecting portion 24 is located in the groove 121. One end of the block 112 close to the connecting portion 24 and at least part of the connecting portion 24 are both located in the groove 121, so that the groove 121 cooperates with the block 112 to realize the positioning and connection of the cover 12 and the body 11, and realize the sealing between two adjacent sub-cavities 113.

[0053] In a specific example, see the attached Figure 1 , Attachment Figure 4 and attached Figure 5 As shown, there are four pole groups 2 arranged along the width direction of the pole group 2, there are three blocks 112, and there are three grooves 121 corresponding to the blocks 112 one by one, so as to divide the cavity 111 into four sub-cavities 113, and the four pole groups 2 correspond to the four sub-cavities 113 one by one.

[0054] In a further embodiment of the utility model, one end of the block 112 facing the cover body 12 is located in the groove 121, and the block 112 is connected to the cover body 12 by gluing. Specifically, glue is injected into the groove 121, and then multiple blocks 112 are matched with multiple grooves 121 respectively. To ensure the matching of the groove 121 and the connecting part 24, the width of the groove 121 is slightly larger than the thickness of the block 112, and the setting of the glue can make up for the extra space for the matching of the groove 121 and the block 112 to ensure the reliability of the bonding and achieve sealing. Preferably, epoxy resin glue is provided in the groove 121, which has good chemical corrosion resistance, heat resistance, toughness and bonding performance, and can ensure the reliability and stability of the connection between the block 112 and the cover body 12.

[0055] In a further embodiment of the present invention, refer to the attached Figure 4 and attached Figure 6 As shown, the cover 12 is provided with a plurality of injection holes 122, and the injection holes 122 correspond one-to-one to the electrode groups 2, and the liquid can be injected into the sub-cavities 113 corresponding to the plurality of electrode groups 2 from the plurality of injection holes 122. In a specific example, there are four electrode groups 2 and four sub-cavities 113, and the four electrode groups 2 are respectively placed in the four sub-cavities 113, and the injection holes 122 correspond one-to-one to the sub-cavities 113, so that the electrolyte can be injected into the four sub-cavities 113 from the four injection holes 122.

[0056] In a further embodiment of the present invention, refer to the attached Figure 6 As shown, the cover 12 is provided with an explosion-proof valve 123, which is arranged opposite to the cavity 111. The setting of the explosion-proof valve 123 can discharge the high-temperature and high-pressure gas inside the sodium ion battery 100, avoid fire and cause serious safety accidents, and improve the safety performance of the sodium ion battery 100. Optionally, the explosion-proof valve 123 is welded to the cover 12 by laser.

[0057] Other structures and operations of the sodium ion battery 100 according to the embodiment of the present invention are known to those skilled in the art and will not be described in detail here.

[0058] 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.

[0059] 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, characterized in that: include: a housing, wherein a cavity is defined in the housing; A plurality of electrode groups are provided in the cavity and arranged along the width direction of the electrode groups, each of the electrode groups has a current collector and a pole ear, the current collector and the pole ear are connected and are both aluminum parts, the pole ears include positive pole ears and negative pole ears, the positive pole ear of one electrode group is directly connected to the negative pole ear or the positive pole ear of another electrode group.

2. The sodium ion battery according to claim 1, characterized in that The positive electrode tab of one of the two adjacent electrode groups is connected to the negative electrode tab or the positive electrode tab of the other electrode group by thermal melting.

3. The sodium ion battery according to claim 1, characterized in that: A plurality of the electrode groups are connected in series.

4. The sodium ion battery according to claim 1, characterized in that The housing comprises: A body, the cavity is arranged on the body, and one side of the cavity is provided with an open opening; A cover body is provided to cover the open opening, and the pole ear is located at one end of the cavity facing the cover body.

5. The sodium ion battery according to claim 4, characterized in that: A block is provided in the cavity, and the block extends along the length direction of the pole group to separate the cavity into a plurality of sub-cavities, and the plurality of pole groups are respectively located in the plurality of sub-cavities.

6. The sodium ion battery according to claim 5, characterized in that: The positive electrode ear and the negative electrode ear both include: A main body and a connecting part, one end of the main body is connected to the connecting part, and the other end is connected to the collector, the connecting parts of the two connected pole ears extend in a direction close to each other, and the connecting part is located on the side of the block facing the cover.

7. The sodium ion battery according to claim 6, characterized in that: A groove matched with the block is provided on one side of the cover body facing the cavity, and at least a part of the connecting portion is located in the groove.

8. The sodium ion battery according to claim 7, characterized in that: One end of the block facing the cover body is located in the groove, and the block is adhesively connected to the cover body.

9. The sodium ion battery according to claim 4, characterized in that: The cover body is provided with a plurality of injection holes, and the injection holes correspond one to one with the electrode groups.

10. The sodium ion battery according to claim 4, characterized in that: The cover body is provided with an explosion-proof valve, and the explosion-proof valve is arranged opposite to the cavity.

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