Single battery and energy storage device

Abstract

The utility model belongs to the technical field of power batteries, and discloses a single battery and an energy storage device. The single battery comprises a shell, a battery cell assembly and a protective part, wherein the battery cell assembly comprises a first pole group and a second pole group, the first pole group and the second pole group are sequentially arranged in the shell along a first direction, and two pole lugs which are close to each other in the first pole group and the second pole group are fixedly connected to form a pole lug connecting part; a groove is formed in the side wall, facing the second pole group, of the first pole group, and the pole lug, facing the second pole group, in the first pole group is arranged in the groove; the protection part is arranged between the first pole group and the second pole group, one side wall of the protection part along the first direction is convexly provided with a fixing part, the fixing part extends into the groove and is provided with a containing cavity, the pole lug connecting part is arranged in the containing cavity, and the containing cavity can be opened and closed. According to the single battery, the capacity, the space utilization rate, the energy density and the structural strength of the single battery are improved, the manufacturing process is simplified, and the yield is high.

Description

Technical Field

[0001] The utility model relates to the technical field of power batteries, in particular to a single battery and an energy storage device. Background Art

[0002] As lithium-ion battery technology becomes increasingly mature, lithium-ion batteries are widely used as power batteries in electric vehicles and energy storage fields. Currently, the requirements for the performance and safety of lithium-ion batteries are increasing.

[0003] Currently, lithium-ion batteries are gradually developing into longer-shaped ones to increase their capacity and energy density. However, due to strength issues, the electrode groups of longer cells often experience bending, deformation, and electrode group movement, resulting in reduced product yield. Furthermore, the molding process requirements for long and particularly long cells are more demanding, increasing manufacturing difficulty. During assembly and use, the tabs of long cells are prone to overlap when bent, resulting in inadequate protection. Furthermore, the tabs are bent in a C- or S-shape to achieve external electrical connection, making the connecting tabs longer and occupying more space, which also affects the energy density of the lithium-ion battery.

[0004] Therefore, there is an urgent need for a new type of single cell battery and energy storage device to solve the above technical problems. Utility Model Content

[0005] One purpose of the present utility model is to provide a single battery cell that can be formed by dividing a long battery cell into two electrode groups connected in series, thereby reducing the manufacturing difficulty and improving the yield rate. In addition, the connection between the electrode groups occupies less space, has high space utilization and high energy density; and at the same time, it is easy to observe and maintain the connection problems of the electrode tabs between the electrode groups.

[0006] To achieve this purpose, the present invention adopts the following technical solutions:

[0007] Single battery, including:

[0008] shell;

[0009] The battery cell assembly includes a first electrode group and a second electrode group, which are sequentially arranged in the above-mentioned housing along a first direction, and two electrode tabs in the above-mentioned first electrode group and the above-mentioned second electrode group that are close to each other are fixedly connected to form an electrode tab connection portion; the side wall of the above-mentioned first electrode group facing the above-mentioned second electrode group is provided with a groove, and the above-mentioned electrode tab in the above-mentioned first electrode group facing the above-mentioned second electrode group is arranged in the above-mentioned groove;

[0010] The protective member is arranged between the above-mentioned first pole group and the above-mentioned second pole group. A fixing portion is protruded from one side wall of the above-mentioned protective member along the above-mentioned first direction. The above-mentioned fixing portion extends into the above-mentioned groove. The above-mentioned fixing portion has an accommodating cavity. The above-mentioned pole ear connecting portion is arranged in the above-mentioned accommodating cavity. The above-mentioned accommodating cavity can be opened and closed.

[0011] Optionally, the protective element includes:

[0012] A support plate is provided between the first pole group and the second pole group;

[0013] The fixing portion is arranged on one side of the above-mentioned support plate along the above-mentioned first direction, and the above-mentioned fixing portion includes two symmetrically arranged protective plates, and the two above-mentioned protective plates enclose the above-mentioned accommodating cavity, and the above-mentioned accommodating cavity is used to accommodate the above-mentioned tab connecting portion; and the above-mentioned protective plate is rotatably connected to the above-mentioned support plate so that the above-mentioned accommodating cavity can be opened and closed.

[0014] Optionally, the protective plate includes:

[0015] A main body portion, rotatably connected to the support plate;

[0016] The limiting portion is arranged on a side of the main body away from the support plate, and the limiting portions of the two protective plates can abut against each other so that the two protective plates are enclosed to form an accommodating cavity.

[0017] Optionally, the flip angle of the protective plate is V, 0°<V<90°.

[0018] Optionally, a dimension of the accommodating cavity along the second direction is H, 1.5 mm < H < 2.5 mm, and the second direction is perpendicular to the first direction.

[0019] Optionally, the groove has a depth of W, 5mm<W<10mm.

[0020] Optionally, an annular side plate is further included, which is sleeved on the outer periphery of the battery cell assembly and abuts against the outer periphery of the battery cell assembly to fix the battery cell assembly.

[0021] Optionally, a plurality of communication holes are provided on the annular side plate to connect the battery cell assembly and the external space of the annular side plate.

[0022] Optionally, first explosion-proof valves are provided at both ends of the housing along the first direction; and / or,

[0023] A second explosion-proof valve is provided on the outer peripheral wall of the shell, and the second explosion-proof valve is provided corresponding to the tab connection portion.

[0024] Another object of the present invention is to provide an energy storage device, comprising a single battery as described in any of the above schemes, which can improve its own space utilization and energy density.

[0025] Beneficial effects of the utility model:

[0026] The utility model provides a single cell battery and energy storage device. By dividing a cell assembly into a first electrode group and a second electrode group connected in series, the capacity of the entire single cell battery is increased and the manufacturing process of long cells is simplified, allowing each cell assembly to be manufactured with the first electrode group and the second electrode group separately, resulting in a high yield rate. A recessed groove recesses a tab of the first electrode group within the body of the first electrode group, allowing the tab connection formed by the tab of the second electrode group connected thereto to be disposed within the recessed groove. This reduces the space occupied by the first and second electrode groups when connected in series, thereby improving the space utilization and energy density of the single cell battery. Furthermore, a protective member is provided between the first and second electrode groups, which not only protects the tab connection but also strengthens the connection between the first and second electrode groups, thereby enhancing the structural strength of the entire single cell battery. The protective member's receptacle is openable and closable, facilitating operator observation and operation of the tab connection of the cell assembly during production, use, maintenance, and testing, without requiring removal of the protective member, saving time and effort. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is an exploded view of a single battery provided in a specific embodiment of the present utility model;

[0028] Figure 2 This is an axonometric diagram of a partial structure of a single battery provided by a specific embodiment of the utility model;

[0029] Figure 3 yes Figure 2 A partial enlarged view of point A in the middle;

[0030] Figure 4 It is an axonometric diagram of the first pole group provided by a specific embodiment of the present utility model;

[0031] Figure 5 is a top view of the first pole group provided in a specific embodiment of the present utility model;

[0032] Figure 6 It is a front view of a protective member provided in a specific embodiment of the present utility model;

[0033] Figure 7 This is an axonometric view of the protective member provided in the embodiment of the present invention in the open state;

[0034] Figure 8 It is a side view of a protective member provided in a specific embodiment of the present utility model;

[0035] Figure 9 It is an axonometric view of the annular side plate provided in a specific embodiment of the present utility model;

[0036] Figure 10 yes Figure 1 A partial enlarged view of point B in the middle.

[0037] In the picture:

[0038] 10. Casing; 11. Housing; 111. Second explosion-proof valve; 12. Cover plate structure; 121. Pole; 122. First explosion-proof valve;

[0039] 20. Cell assembly; 201. Tab; 21. First pole group; 211. Groove; 22. Second pole group;

[0040] 30. Protective element; 301. Accommodating chamber; 31. Support plate; 311. Support seat; 32. Protective plate; 321. Main body; 322. Limiting portion; 323. Rotating axis;

[0041] 40. Annular side plate; 41. Communication hole; 42. First plate; 43. Second plate;

[0042] 50. Insulating film; 51. Slit. DETAILED DESCRIPTION

[0043] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0044] In the description of this utility model, unless otherwise expressly specified or limited, the terms "connected," "connected," and "fixed" should be understood in a broad sense. For example, they may refer to fixed connection, detachable connection, or integration; they may refer to direct connection or indirect connection through an intermediate medium; they may refer to internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0045] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0046] In the description of this embodiment, the terms "upper," "lower," "left," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0047] Refer to the following Figures 1 to 10 The utility model introduces a single battery and an energy storage device.

[0048] It should be noted that the first direction is Figure 1 The X direction in the second direction is Figure 1 The Y direction in the third direction is Figure 1 In the Z direction, the X direction, Y direction and Z direction are perpendicular to each other.

[0049] Please refer to Figures 1 to 3 This embodiment provides a single battery, which includes a housing 10, a battery cell assembly 20 and a protective member 30; wherein the battery cell assembly 20 includes a first electrode group 21 and a second electrode group 22, the first electrode group 21 and the second electrode group 22 are sequentially arranged in the housing 10 along a first direction, and two electrode tabs 201 close to each other in the first electrode group 21 and the second electrode group 22 are fixedly connected to form an electrode tab connection portion; Figure 4 and Figure 5 As shown, a groove 211 is provided on the side wall of the first pole group 21 facing the second pole group 22, and the pole ear 201 in the first pole group 21 facing the second pole group 22 is arranged in the groove 211; the protective member 30 is arranged between the first pole group 21 and the second pole group 22, and a fixing portion is protruded from one side wall of the protective member 30 along the first direction, and the fixing portion extends into the groove 211, and the fixing portion has an accommodating cavity 301, and the pole ear connecting portion is arranged in the accommodating cavity 301, and the accommodating cavity 301 can be opened and closed.

[0050] The single cell battery in this embodiment is constructed by dividing the cell assembly 20 into a first electrode group 21 and a second electrode group 22 connected in series. This not only increases the capacity of the entire single cell battery, but also simplifies the manufacturing process of long cells, allowing each cell assembly 20 to be manufactured with the first electrode group 21 and the second electrode group 22 separately, resulting in a high yield rate. The recess 211 recesses one of the tabs 201 of the first electrode group 21 within the body of the first electrode group 21, allowing the tab connection formed by the tab 201 of the second electrode group 22 connected thereto to be disposed within the recess 211. This saves space when the first and second electrode groups 21, 22 are connected in series, thereby improving the space utilization and energy density of the single cell battery. Furthermore, a protective member 30 is provided between the first and second electrode groups 21, 22, which not only protects the tab connection but also increases the strength of the connection between the first and second electrode groups 21, 22, thereby improving the structural strength of the entire single cell battery. Moreover, the accommodating cavity 301 of the protective member 30 can be opened and closed, which makes it convenient for operators to observe and operate the tab connection of the battery cell assembly 20 during production, use, maintenance and testing, without the need to disassemble the protective member 30, saving time and effort.

[0051] It can be understood that the two electrode tabs 201 of the first electrode group 21 and the second electrode group 22 that are close to each other are horizontally overlapped and then fixedly connected, so as to simplify the manufacturing process and further reduce the internal resistance.

[0052] Please refer to Figure 4 and Figure 5 Optionally, the groove 211 has a depth of W, 5mm<W<10mm. This setting can meet the placement space of the pole ear 201, so that the connection between the two pole groups is only provided with the support plate 31 for insulation support, and there is no other space, thereby improving space utilization.

[0053] Please refer to Figure 3 、 Figures 6 to 8 Specifically, the protective member 30 includes a support plate 31 and a fixing portion. The support plate 31 is arranged between the first pole group 21 and the second pole group 22 to maintain the inductive balance and insulation isolation of the two pole groups when they are placed in the shell; the fixing portion is arranged on one side of the support plate 31 along the first direction, and the fixing portion includes two symmetrically arranged protective plates 32, and the two protective plates 32 enclose a receiving cavity 301, and the receiving cavity 301 is used to receive the pole tab connection portion; and the protective plate 32 is rotatably connected to the support plate 31 so that the receiving cavity 301 can be opened and closed. When installing, the protective plate 32 can be rotated to open the receiving cavity 301 to facilitate the installation of the support plate 31 and the covering of the pole tab connection portion by the protective plate 32, or the protective member 30 can be installed with the first pole group 21 and the second pole group 22, and then the protective plate 32 can be opened to fix the pole tabs 201 of the two pole groups. Both of the above methods can achieve the installation of the protective member 30 and the balanced fixation of the battery cell assembly 20.

[0054] Specifically, the support plate 31 includes a support seat 311 , a matching hole is opened on the support seat 311 , and a rotating shaft 323 is provided on the protective plate 32 . The rotating shaft 323 is rotatably connected to the matching hole to realize the rotation of the protective plate 32 .

[0055] Optionally, the matching hole and the rotating shaft 323 are interference-connected so that the protective plate 32 can rotate only when driven by an external force, thereby preventing it from rotating automatically and exposing the tab connection portion it protects, thereby improving the safety of the single battery.

[0056] Specifically, the protective plate 32 includes a main body 321 and a limiting portion 322. The main body 321 is rotatably connected to the support plate 31; the limiting portion 322 is arranged on the side of the main body 321 away from the support plate 31. The limiting portions 322 of the two protective plates 32 can abut against each other, so that the two protective plates 32 are enclosed to form an accommodating cavity 301, thereby avoiding the two protective plates 32 from crushing the pole ear 201, thereby improving the balance, fixation and protection capabilities of the pole ear 201.

[0057] Optionally, the flip angle of the protective plate 32 is V, 0°<V<90°, which can meet the requirements of opening and closing of the protective plate 32.

[0058] Optionally, the dimension of the accommodating cavity 301 along the second direction is H, 1.5 mm<H<2.5 mm, which can fully accommodate the tab connection portion after the two tabs 201 are connected.

[0059] Please refer to Figure 2 and Figure 9 In some embodiments, the battery cell further includes an annular side plate 40, which is sleeved around the periphery of the cell assembly 20 and abuts against the periphery of the cell assembly 20 to secure the cell assembly 20. This reinforces the cell assembly 20, providing it with a certain structural strength and preventing deformation and other issues that could affect the safety of the battery cell. Furthermore, this ensures insulation between the cell assembly 20 and the housing 11 along the first direction, balancing the thrust when the cell assembly 20 and the annular side plate 40 are inserted into the housing.

[0060] Specifically, the annular side plate 40 is further provided with through holes on both sides along the first direction to facilitate the insertion of the pole ear 201, so that the pole ear 201 is connected to the pole 121 of the shell 10, while also ensuring the insulation setting of the main body 321 of each pole group and the shell 10 along the first direction.

[0061] Optionally, the dimension of the annular side plate 40 along the second direction is smaller than the dimension of the battery cell assembly 20 along the second direction to form an annular airway to facilitate the discharge of gas; when the battery cell assembly 20 suffers thermal runaway, the gas can flow out quickly through the annular airway to release the pressure inside the single cell and improve the safety of the single cell.

[0062] Specifically, the annular side plate 40 includes a plurality of first plates 42 and a plurality of second plates 43, and the first plates 42 and the second plates 43 are alternately connected and arranged, and the size of the second plate 43 along the second direction is smaller than the size of the first plate 42 along the second direction, so that the gas storage area between the second plate 43 and the inner wall of the outer shell 10 is increased, and the volume of the annular airway is increased, so that the gas on the other surfaces of each pole group can flow into the annular airway through the gas storage space between the second plate 43 and the inner wall of the outer shell 10 and be discharged smoothly; and effectively increase the gas occupied space inside the outer shell 10 of the single cell, slow down the rising rate of the pressure inside the single cell, and further improve the safety of the single cell.

[0063] Optionally, a plurality of connecting holes 41 are provided on the annular side plate 40 to connect the battery cell assembly 20 and the external space of the annular side plate 40, so that each pole group in the battery cell assembly 20 can be in full contact with the electrolyte, and at the same time, the gas generated by thermal runaway of each pole group can also be discharged through the connecting hole 41.

[0064] Optionally, the annular side plate 40 and the protective member 30 are both made of insulating materials and formed by injection molding, which has a simple molding process and high precision.

[0065] Please refer back to Figure 1 In some embodiments, the housing 10 includes a shell 11 and two cover structures 12. The shell 11 is provided with openings at both ends along the first direction. The two cover structures 12 are respectively sealed and connected to the two openings to achieve the airtightness of the housing 10, and the openings facilitate the entry of the battery cell assembly 20 into the shell.

[0066] Specifically, a pole 121 is provided on the cover structure 12 , and the pole 121 is electrically connected to the pole tab 201 on either side of the battery cell assembly 20 along the first direction to achieve external electrical connection of the single battery.

[0067] Optionally, the cover plate structure 12 does not need upper plastic, lower plastic and other structures, which are replaced by the annular side plate 40, which not only simplifies the structure, but also reduces costs and improves space utilization.

[0068] In some embodiments, first explosion-proof valves 122 are provided at both ends of the housing 10 along the first direction; that is, the cover structure 12 is provided with first explosion-proof valves 122 to achieve explosion-proof and pressure-relieving effects for the single battery.

[0069] In some embodiments, a second explosion-proof valve 111 is provided on the outer wall of the shell 10, and the second explosion-proof valve 111 is arranged corresponding to the pole ear connection part, that is, the second explosion-proof valve 111 is provided in the middle position of the shell 11 along the first direction to shorten the length of the explosion-proof pressure relief exhaust, thereby accelerating the discharge of gas and improving the explosion-proof pressure relief effect of the single cell.

[0070] Optionally, the second explosion-proof valve 111 is provided on any side wall of the housing 11 along the third direction, so that it occupies smaller space and improves space utilization.

[0071] Please refer to Figure 1 and Figure 10 In some embodiments, the single battery further includes an insulating film 50 , which is coated on the periphery of the battery cell assembly 20 and the annular side plate 40 to provide insulation protection between the shell 11 and the battery cell assembly 20 .

[0072] Optionally, the thickness of the insulating film 50 is T, 0.1 mm < T < 0.3 mm, which can satisfy the insulating protection effect of the insulating film 50 on the battery cell assembly 20 and does not occupy more space in the single battery.

[0073] Optionally, a slit 51 is provided at a position corresponding to the insulating film 50 and the second explosion-proof valve 111, and the slit 51 is used to weaken the structural strength at that position so that the gas inside the shell 11 can smoothly reach the second explosion-proof valve 111 for pressure relief, making it easier for the second explosion-proof valve 111 to vent and open.

[0074] This embodiment also provides an energy storage device comprising the single cell battery described in any of the above-mentioned solutions. The energy storage device is a structure, such as a battery module or battery pack, that incorporates the single cell battery and provides both power storage and external power supply. By utilizing the above-mentioned single cell battery, the energy storage device not only increases capacity and energy density but also improves structural strength and safety.

[0075] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. A single cell battery, characterized in that: include: shell; A battery cell assembly includes a first electrode group and a second electrode group, wherein the first electrode group and the second electrode group are sequentially arranged in the housing along a first direction, and two electrode tabs in the first electrode group and the second electrode group that are close to each other are fixedly connected to form an electrode tab connection portion; a groove is provided on the side wall of the first electrode group facing the second electrode group, and the electrode tab in the first electrode group facing the second electrode group is arranged in the groove; A protective member is arranged between the first pole group and the second pole group. A fixing portion is protruded from one side wall of the protective member along the first direction. The fixing portion extends into the groove. The fixing portion has an accommodating cavity. The pole ear connecting portion is arranged in the accommodating cavity. The accommodating cavity can be opened and closed.

2. The single cell according to claim 1, characterized in that: The protective element comprises: a support plate, disposed between the first pole group and the second pole group; A fixing portion is arranged on one side of the support plate along the first direction, and the fixing portion includes two symmetrically arranged protective plates, which enclose the two protective plates to form the accommodating cavity, and the accommodating cavity is used to accommodate the tab connecting portion; and the protective plate is rotatably connected to the support plate so that the accommodating cavity can be opened and closed.

3. The single cell according to claim 2, characterized in that: The protective plate comprises: A main body portion, rotatably connected to the support plate; The limiting portion is arranged on a side of the main body away from the support plate, and the limiting portions of the two protective plates can abut against each other so that the two protective plates enclose and form the accommodating cavity.

4. The single cell according to claim 2, characterized in that: The flip angle of the protective plate is V, 0°<V<90°.

5. The single cell according to claim 2, characterized in that: The dimension of the accommodating cavity along the second direction is H, 1.5 mm<H<2.5 mm, and the second direction is perpendicular to the first direction.

6. The single cell according to claim 1, characterized in that: The groove has a depth of W, 5mm<W<10mm.

7. The single cell according to claim 1, characterized in that: It also includes an annular side plate, which is sleeved on the outer periphery of the battery core assembly and abuts against the outer periphery of the battery core assembly to fix the battery core assembly.

8. The single cell according to claim 7, characterized in that: The annular side plate is provided with a plurality of communication holes for connecting the battery core assembly and the external space of the annular side plate.

9. The single cell according to any one of claims 1 to 8, characterized in that: Both ends of the housing along the first direction are provided with first explosion-proof valves; and / or, A second explosion-proof valve is provided on the outer peripheral wall of the shell, and the second explosion-proof valve is arranged corresponding to the tab connecting portion.

10. An energy storage device, characterized in that The invention comprises a single cell according to any one of claims 1 to 9.

Images