Lithium battery, battery pack and energy storage product

Abstract

A lithium battery, comprising: a case and at least two battery cells connected in series, wherein the case is provided with at least two independent accommodating cavities; the battery cells are correspondingly arranged in the accommodating cavities; each battery cell is provided with a first positive electrode portion and a first negative electrode portion; the case is further provided with an exposed second positive electrode portion and second negative electrode portion; the first positive electrode portion is connected to the second positive electrode portion; and the first negative electrode portion is connected to the second negative electrode portion. A battery pack and an energy storage product. The at least two battery cells are correspondingly arranged in the at least two accommodating cavities, respectively; in addition, the battery cells are connected in series, and positive electrodes and negative electrodes of the battery cells connected in series are led out by means of the second positive electrode portion and the second negative electrode portion, thus ameliorating the situation where existing lithium batteries are each provided with only a single battery cell; moreover, the energy density (ED) of the battery is increased, such that the battery can meet the current requirement for high ED of lithium batteries.

Description

Lithium batteries, battery packs and energy storage products Technical Field

[0001] The present application relates to the field of battery technology, and in particular, to a lithium battery, a battery pack, and an energy storage product. Background Art

[0002] Square steel shell battery is one of the types of lithium batteries. Due to the advantages of lithium batteries themselves, square steel shell battery is widely used. At the same time, square steel shell battery also has the characteristics of simple process, mature technology and low cost.

[0003] Prismatic steel-cased batteries consist of a housing and a cell. The cell sits inside the housing, which also features a structure for leading out the positive and negative electrodes. The positive and negative tabs on the cell connect to the positive and negative structures, respectively. During use, the current flows through the positive and negative electrodes. Currently, this type of battery suffers from a low energy density (ED), making it difficult to meet the current demands for higher ED.

[0004] Summary of the Invention

[0005] In response to the deficiencies in the prior art, the present application provides a lithium battery, a battery pack, and an energy storage product.

[0006] A lithium battery disclosed in the present application includes: a shell and at least two battery cells connected in series, the shell having at least two independent accommodating cavities, and the battery cells are correspondingly arranged in the accommodating cavities; the battery cell has a first positive electrode portion and a first negative electrode portion, and the shell also has an exposed second positive electrode portion and a second negative electrode portion, the first positive electrode portion is connected to the second positive electrode portion, and the first negative electrode portion is connected to the second negative electrode portion.

[0007] According to one embodiment of the present application, the shell includes an upper shell, a lower shell and a partition. The upper shell covers the lower shell, the partition is located between the upper shell and the lower shell, the partition and the upper shell form a accommodating cavity, and the partition and the lower shell form another accommodating cavity.

[0008] According to one embodiment of the present application, the shell further includes a first pole and a second pole with opposite polarities, the first pole and the second pole are respectively insulated and connected to the upper shell and the lower shell, and the first positive pole and the first negative pole are respectively connected to the first pole and the second pole.

[0009] According to one embodiment of the present application, the battery cell has a single-pole structure.

[0010] According to one embodiment of the present application, the shell also includes another set of third poles and fourth poles with opposite polarity and connected to each other. The third pole and the fourth pole are respectively arranged on the upper shell and the lower shell. The third pole has an opposite polarity to the first pole, and the fourth pole has an opposite polarity to the second pole.

[0011] According to one embodiment of the present application, a connecting plate is further included, and the connecting plate is respectively connected to the third pole and the fourth pole.

[0012] According to one embodiment of the present application, the battery cell has a bipolar tab structure.

[0013] According to one embodiment of the present application, a conductive glue is further included, and the battery core is connected to the wall surface of the accommodating cavity through the conductive glue.

[0014] The present application discloses a battery pack comprising: a plurality of the above-mentioned lithium batteries.

[0015] The present application discloses an energy storage product, including: the above-mentioned battery pack.

[0016] The beneficial effect of the present application is that at least two battery cells are respectively arranged in at least two accommodating cavities, and at the same time, the battery cells are connected in series, and the positive and negative poles of the series-connected battery cells are led out through the second positive electrode part and the second negative electrode part, thereby improving the situation in which there is only a single battery cell in the existing lithium battery. At the same time, the energy density of the battery is improved, so that it can meet the current demand for high ED of lithium batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0018] Figure 1 is a schematic diagram of the three-dimensional structure of a lithium battery;

[0019] Figure 2 is a disassembled structure diagram of a lithium battery;

[0020] FIG3 is a partial cross-sectional view of a lithium battery;

[0021] FIG4 is another schematic diagram of the three-dimensional structure of a lithium battery;

[0022] Figure 5 is another disassembled structure diagram of a lithium battery.

[0023] Description of Reference Numerals

[0024] 1-shell; 11-accommodation cavity; 12-second positive electrode portion; 13-second negative electrode portion; 14-upper shell; 15-lower shell; 16-partition; 17-first pole; 18-second pole; 19-third pole; 10-fourth pole;

[0025] 2-battery cell; 21-first positive electrode portion; 22-first negative electrode portion;

[0026] 3-Connection plate. DETAILED DESCRIPTION

[0027] The following diagrams illustrate various embodiments of the present application. For clarity, many practical details will be included in the following description. However, it should be understood that these practical details are not intended to limit the present application. In other words, in some embodiments of the present application, these practical details are not essential. Furthermore, to simplify the drawings, some conventional structures and components are depicted in a simplified schematic manner.

[0028] In addition, in this application, descriptions such as "first" and "second" are only used for descriptive purposes and do not specifically refer to the order or ranking, nor are they used to limit this application. They are only used to distinguish components or operations described with the same technical terms, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0029] Example 1

[0030] As shown in Figures 1 to 3, Figure 1 is a schematic diagram of the three-dimensional structure of a lithium battery; Figure 2 is a disassembled structural diagram of a lithium battery; and Figure 3 is a partial cross-sectional view of a lithium battery. The lithium battery of the present application includes a shell 1 and at least two battery cells 2, wherein at least two battery cells 2 are arranged in series in the shell 1. In specific applications, a single battery cell 2 has a first positive electrode portion 21 and a first negative electrode portion 22. Correspondingly, the shell 1 has a second positive electrode portion 12 and a second negative electrode portion 13. When the battery cell 2 is placed in the shell 1, the first positive electrode portion 21 is connected to the second positive electrode portion 12 and is conductive, and the first negative electrode portion 22 is connected to the second negative electrode portion 13 and is conductive. To further illustrate, this embodiment will be described with the battery cell 2 as a single-pole sheet structure, that is, a pole ear of one polarity extends from the battery cell 2, and the pole ear can be the positive pole of the battery cell 2 or the negative pole of the battery cell 2; it is assumed here that the battery cell 2 is wound with a copper foil end, and the pole ear extending from the battery cell 2 is the cathode pole ear; synchronously, the other battery cell 2 will be wound with an aluminum foil end, and the pole ear extending from the battery cell 2 is the anode pole ear.

[0031] The shell 1 includes an upper shell 14, a lower shell 15 and a partition 16. The upper shell 14 and the lower shell 15 are covered and connected, and after the upper shell 14 and the lower shell 15 are covered, the two form a accommodating cavity 11. The partition 16 is located between the upper shell 14 and the lower shell 15. At the same time, the accommodating cavity 11 is divided into two by the setting of the partition 16, that is, there are two accommodating cavities 11 inside the shell 1, and each accommodating cavity 11 is provided with a battery cell 2. Since the number of accommodating cavities 11 and battery cells 2 can be increased according to demand, the number of accommodating cavities 11 and battery cells 2 will not be limited in this embodiment, and two battery cells 2 and two accommodating cavities 11 will be used as an example for introduction.

[0032] In specific applications, the housing 1 also includes a first pole 17 and a second pole 18, wherein the first pole 17 and the second pole 18 have opposite polarity, whereby one pole is positive and the other is negative. The first pole 17 is disposed on the outer surface of the upper housing 14 and is insulated from the upper housing 14. The second pole 18 is disposed on the outer surface of the lower housing 15 and is insulated from the lower housing 15. In this way, a positive pole and a negative pole are formed on the exterior of the entire housing 1.

[0033] During use, a battery cell 2 with a copper foil end is placed in a receiving cavity 11 at an upper shell 14 body 1, and the cathode electrode tab extending from the battery cell 2 is connected to the first pole 17 (that is, the first pole 17 serves as the positive pole of the lithium battery) and is conductive, and the copper foil area of ​​the battery cell 2 is connected to the wall or partition 16 of the receiving cavity 11; another battery cell 2 with an aluminum foil end is placed in the receiving cavity 11 at another lower shell 15, and the anode electrode tab extending from the battery cell 2 is connected to the second pole 18 (that is, the second pole 18 serves as the negative pole of the lithium battery) and is conductive, and the aluminum foil area of ​​the battery cell 2 is connected to the wall or partition 16 of the receiving cavity 11; at this point, the two battery cells 2 are connected in series through the upper shell 14, the lower shell 15 or the partition 16. This method is beneficial to reducing the current loss in the circuit and reducing the degree of heat generated during the use of the product. At the same time, it meets the needs of fast charging and ensures the safety of lithium battery use.

[0034] Furthermore, the connection between the cell 2 and the upper shell 14, lower shell 15 or partition 16 can be made by bonding with conductive adhesive, which fixes the position of the cell 2 to ensure the stability of the current conduction. The conductive adhesive is an existing material and will not be elaborated here.

[0035] It should also be noted that in this embodiment, the first positive portion 21 of the battery cell 2 located within the accommodating cavity 11 formed by the upper shell 14 and the separator 16 is the extended cathode tab, and the first negative portion 22 is the area where the copper foil ends. The first positive portion 21 of the battery cell 2 located within the accommodating cavity 11 formed by the lower shell 15 and the separator 16 is the area where the aluminum foil ends, and the first negative portion 22 is the extended anode tab. Correspondingly, the second positive portion 12 of the shell 1 is the first terminal 17, and the second negative portion 13 of the shell 1 is the second terminal 18.

[0036] To sum up, at least two battery cells 2 are respectively arranged in at least two accommodating cavities 11. At the same time, the battery cells 2 are connected in series, and the positive and negative poles of the series-connected battery cells 2 are led out through the second positive electrode portion 12 and the second negative electrode portion 13, thereby improving the situation in which there is only a single battery cell 2 in the existing lithium battery. At the same time, the energy density of the battery is improved, so that it can meet the current demand for high ED of lithium batteries.

[0037] Example 2

[0038] As shown in Figures 4 and 5, Figure 4 is another schematic diagram of the three-dimensional structure of the lithium battery; Figure 5 is another disassembled structure diagram of the lithium battery. The difference between this embodiment and the first embodiment is that the battery cell 2 in this embodiment has a bipolar tab structure, that is, a battery cell 2 will extend a cathode tab and an anode tab at the same time. The shell 1 also includes a third pole 19 and a fourth pole 10 connected to each other. The polarity of the third pole 19 and the fourth pole 10 are opposite. The third pole 19 is arranged on the outer surface of the upper shell 14, and the fourth pole 10 is arranged on the outer surface of the lower shell 15. The third pole 19 does not need to be insulated from the upper shell 14, and the third pole 19 does not need to be insulated from the lower shell 15. The cathode tab and anode tab of one battery cell 2 are respectively connected to the first pole 17 and the third pole 19 of the upper shell 14, and the cathode tab and anode tab of the other battery cell 2 are respectively connected to the fourth pole 10 and the second pole 18 of the lower shell 15.

[0039] Furthermore, the lithium battery further includes a connecting plate 3 , two ends of which are respectively connected to the third pole 19 and the fourth pole 10 , so that the third pole 19 and the fourth pole 10 are electrically connected via the connecting plate 3 .

[0040] It should also be noted that in this embodiment, the battery cell 2 located within the accommodating cavity 11 formed by the upper shell 14 and the separator 16 has its first positive electrode portion 21 as the extended cathode tab, and its first negative electrode portion 22 as the area where the copper foil ends and the extended anode tab. The battery cell 2 located within the accommodating cavity 11 formed by the lower shell 15 and the separator 16 has its first positive electrode portion 21 as the area where the aluminum foil ends and the extended cathode tab, and its first negative electrode portion 22 as the extended anode tab. Correspondingly, the second positive electrode portion 12 in the shell 1 is the first pole 17 and the fourth pole 10, and the second negative electrode portion 13 in the shell 1 is the second pole 18 and the third pole 19.

[0041] Example 3

[0042] The battery pack in this embodiment includes multiple lithium batteries, which are conductively connected. The lithium batteries have the structure of the first embodiment, which is described in detail in the above structure and will not be repeated here.

[0043] Example 4

[0044] The battery pack in this embodiment includes multiple lithium batteries, which are conductively connected. The lithium batteries have the structure of the second embodiment, which is described in detail above and will not be repeated here.

[0045] Example 5

[0046] The energy storage product in this embodiment includes a battery pack, wherein the battery pack adopts the structure of the third embodiment. Please refer to the above structure introduction for details, which will not be repeated here.

[0047] Example 6

[0048] The energy storage product in this embodiment includes a battery pack, wherein the battery pack adopts the structure of the fourth embodiment. Please refer to the above structure introduction for details, which will not be repeated here.

[0049] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should be included within the scope of the claims of the present application.

Claims

1. A lithium battery, characterized in that: include: A shell (1) and at least two battery cells (2) connected in series, the shell (1) having at least two independent accommodating chambers (11), the battery cells (2) being arranged correspondingly in the accommodating chambers (11); the battery cells (2) having a first positive electrode portion (21) and a first negative electrode portion (22), the shell (1) also having an exposed second positive electrode portion (12) and a second negative electrode portion (13), the first positive electrode portion (21) being connected to the second positive electrode portion (12), and the first negative electrode portion (22) being connected to the second negative electrode portion (13).

2. The lithium battery according to claim 1, characterized in that: The shell (1) comprises an upper shell (14), a lower shell (15) and a partition (16); the upper shell (14) covers the lower shell (15); the partition (16) is located between the at least two battery cells (2) connected in series; the partition (16) and the upper shell (14) form one accommodating cavity (11); and the partition (16) and the lower shell (15) form another accommodating cavity (11).

3. The lithium battery according to claim 2, characterized in that: The shell (1) further comprises a first pole (17) and a second pole (18) of opposite polarities, the first pole (17) and the second pole (18) are respectively insulated and connected to the upper shell (14) and the lower shell (15), and the first positive pole portion (21) and the first negative pole portion (22) are respectively connected to the first pole (17) and the second pole (18).

4. The lithium battery according to claim 3, characterized in that: The battery core (2) is a single-pole ear structure.

5. The lithium battery according to claim 3, characterized in that: The shell (1) further comprises another set of a third pole (19) and a fourth pole (10) of opposite polarity and connected to each other, wherein the third pole (19) and the fourth pole (10) are respectively arranged on the upper shell (14) and the lower shell (15), the third pole (19) and the first pole (17) having opposite polarity, and the fourth pole (10) and the second pole (18) having opposite polarity.

6. The lithium battery according to claim 5, characterized in that: It also comprises a connecting plate (3), wherein the connecting plate (3) is respectively connected to the third pole (19) and the fourth pole (10).

7. The lithium battery according to claim 5, characterized in that: The battery core (2) is a bipolar lug structure.

8. The lithium battery according to any one of claims 1 to 7, characterized in that: It also includes conductive glue, and the battery core (2) is connected to the wall surface of the accommodating cavity (11) via the conductive glue.

9. A battery pack, characterized in that: include: A plurality of lithium batteries according to any one of claims 1 to 8.

10. An energy storage product, characterized in that: Comprising the battery pack as claimed in claim 9.

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