Battery cell and battery pack

Abstract

The utility model relates to the technical field of batteries, and discloses a battery cell and a battery pack. Wherein the battery cell comprises a shell, a battery core and a battery cover, and a pole is integrated in the shell; the pole group is arranged in the shell and is provided with a pole lug, the pole lug and the pole column are arranged in a staggered manner, and the pole lug comprises a body connected with the pole group and a bending part which is bent towards one side from the end part of the body; and the connecting sheet is arranged in the shell, is positioned on the pole group, is used for connecting the pole column and the pole lug, is fixed in a space defined by the body and the bending part, and is attached to the lower surface of the bending part. According to the utility model, the poles and the tabs are arranged in a staggered manner, so that the space in the length direction in the shell is utilized, the space in the shell, which is occupied by the poles and the tabs in the height direction of the shell in a connecting state, is shortened, the utilization rate of the space in the shell is improved, and further, the battery cell can store more energy under the same volume. And secondly, the tabs are connected with the connecting sheets through the bending parts, so that the operation difficulty of connecting the tabs with the connecting sheets can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of batteries, and particularly relates to an electric core and a battery pack. Background Art

[0002] The connecting piece in the electric core is a metal piece used to connect the pole column of the electric core and the ear of the pole group. It ensures the smooth flow of current between the pole column and the ear, and realizes the storage and release of electric energy of the electric core.

[0003] However, the method of connecting the connecting piece and the ear adopted in the related art is not only relatively complicated to operate, but also occupies a relatively large internal space of the electric core. Summary of the Utility Model

[0004] In view of this, the utility model provides an electric core and a battery pack to solve the problems that the connection method between the connecting piece and the ear in the related art is complicated and occupies a relatively large internal space of the electric core.

[0005] In a first aspect, the utility model provides an electric core, including:

[0006] A housing, internally integrated with a pole column;

[0007] A pole group, arranged in the housing and provided with ears, the ears are arranged in a dislocation manner with respect to the pole column, the ears include a body connected to the pole group and a bent portion bent from an end of the body towards one side;

[0008] A connecting piece, arranged in the housing and located on the pole group, used to connect the pole column and the ears, the connecting piece is fixed in the space defined by the body and the bent portion and is attached to the lower surface of the bent portion.

[0009] Beneficial effects: The pole column and the ears of the utility model are arranged in a dislocation manner, making use of the space in the length direction inside the housing. Compared with the existing situation where both the connecting piece and the ears are arranged along the axial direction of the pole column, the internal space of the housing occupied by the connecting piece and the ears in the connection state in the height direction of the housing is reduced, the utilization rate of the internal space of the housing is improved, and thus the electric core can store more energy under the same volume. Secondly, the ears are connected to the connecting piece through the bent portion, which can reduce the operation difficulty of connecting the ears and the connecting piece, and also reduce the occupation of the internal space of the housing when they are in the connection state.

[0010] In an optional implementation manner, the body is perpendicularly arranged with respect to the bent portion.

[0011] Beneficial effects: The utility model perpendicularly arranges the body of the ear and the bent portion of the ear, which can make the structure of the ear in the housing more compact, optimize the internal space of the housing, and improve the energy density of the electric core.

[0012] In an alternative embodiment, the height of the body is adapted to the thickness of the connecting piece.

[0013] Advantageous effects: In the utility model, the height of the body in the tab is adapted to the thickness of the connecting piece. On the one hand, the lower surface of the bending part can be closely attached to the connecting piece, so that not only the connection stability between the two can be enhanced, but also the contact resistance can be reduced, and the transmission efficiency of the current between the tab and the terminal can be improved. On the other hand, the structure of the connecting piece and the tab in the connected state can be made more compact, reducing the unnecessary occupation of the internal space of the housing.

[0014] In an alternative embodiment, the connecting piece includes a terminal connecting part connected to the terminal and a tab connecting part connected to the tab, and a transition connecting part is formed between the tab connecting part and the terminal connecting part.

[0015] Advantageous effects: Since the tabs and terminals in the utility model are arranged in a staggered manner, the connecting piece is divided into a terminal connecting part and a tab connecting part, which can make the position of the connecting piece adapt to the tabs and terminals, so that the tabs and terminals can be connected, realizing the smooth flow of current between the tabs and the terminals. In addition, by forming a transition connecting part between the tab connecting part and the terminal connecting part, the stress concentration phenomenon between the tab connecting part and the terminal connecting part can be avoided, ensuring the connection strength between the two.

[0016] In an alternative embodiment, a pair of the connecting pieces are arranged at intervals along the length direction of the electrode group, and the tabs are respectively arranged on the opposite sides of each connecting piece. The tabs on the opposite sides are respectively located on the opposite sides of the tab connecting part along the width direction of the electrode group, and their respective bending parts are bent and extended towards each other.

[0017] Advantageous effects: Since the terminals on the housing are divided into a positive terminal and a negative terminal, and the tabs on the electrode group are divided into a positive tab and a negative tab, by arranging a pair of connecting pieces on the electrode group, not only the positive terminal and the positive tab can be connected, but also the negative terminal and the negative tab can be connected, so that the stable transmission of current between the tabs and the terminals can be ensured, reducing the problem of poor contact. Secondly, arranging the pair of connecting pieces at intervals can avoid the short circuit between the positive terminal and the negative terminal, improving the safety of the battery cell during use. Moreover, making the tabs on the opposite sides be respectively located on the opposite sides of the tab connecting part along the width direction of the electrode group makes the structure inside the battery cell more compact, thereby improving the space utilization rate inside the housing.

[0018] In an alternative embodiment, a gap is left between the ends of the bending parts on the opposite sides that are close to each other.

[0019] Beneficial effects: Compared with stacking the bent portions of two tabs on one connecting piece, the present utility model leaves a gap between the ends of the bent portions on the opposite sides that are close to each other, which can reduce the thickness when the two tabs are in a connected state with one connecting piece, that is, reduce the occupation of the internal space of the housing and improve the energy density of the battery cell.

[0020] In an alternative embodiment, a notch extending along the length direction of the electrode group is provided on the tab connecting portion, and the notch divides the tab connecting portion into two sub-connecting portions. The two sub-connecting portions correspond to a pair of tabs one by one and are respectively welded to the lower surfaces of the corresponding bent portions.

[0021] Beneficial effects: Since the welding method between the bent portion and the connecting piece can adopt ultrasonic welding, compared with taking the tab connecting portion as a whole, the present utility model uses the notch to divide the tab connecting portion into two sub-connecting portions, which can avoid the influence of the vibration generated during the ultrasonic welding process on the entire tab connecting portion and ensure the stability and quality of the welding between each sub-connecting portion and the corresponding tab.

[0022] In an alternative embodiment, two through holes are provided on the housing, and the two through holes are arranged corresponding to the two tab connecting portions, and a sealing plate is provided on the through holes.

[0023] Beneficial effects: The present utility model provides a suitable operation space for the operator by providing through holes corresponding to the tab connecting portions on the housing, so that the operator can complete the operation of bending the bent portion towards the connecting piece and the operation of welding the lower surface of the bent portion to the connecting piece. Secondly, by providing a sealing plate on the through hole, the sealing performance of the housing can be improved, and the possibility of external impurities entering the interior of the battery cell can be reduced.

[0024] In an alternative embodiment, an explosion-proof valve is further provided on the housing, and the explosion-proof valve is located between the two through holes.

[0025] Beneficial effects: By providing an explosion-proof valve on the housing, the present utility model can automatically open when the internal pressure of the battery cell exceeds the safety threshold, release the internal gas, and prevent the battery cell from exploding due to excessive internal pressure. Secondly, by arranging the explosion-proof valve between the two through holes, the space on the surface of the housing can be fully utilized, making the overall structure of the battery cell more compact.

[0026] In a second aspect, the present utility model further provides a battery pack, including: a plurality of the above-mentioned battery cells.

[0027] Beneficial effects: By adopting the above-mentioned battery cells, the battery pack of the present utility model can improve its own space utilization rate, so that without changing its own volume, its energy density can be increased, its service time can be extended or the charging frequency can be reduced. In addition, the battery pack of the present utility model has all the advantages of the above-mentioned battery cells, which will not be elaborated here. Description of the drawings

[0028] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 Structural schematic diagram of a battery cell according to an embodiment of the present utility model;

[0030] Figure 2 It is Figure 1 Structural schematic diagram without installing the sealing plate;

[0031] Figure 3 It is Figure 2 Structural schematic diagram without installing the housing;

[0032] Figure 4 It is Figure 2 Top view schematic diagram of

[0033] Figure 5 It is Figure 4 Cross-sectional view schematic diagram along the A-A view angle;

[0034] Figure 6 Structural schematic diagram of the tab and the connecting piece not connected according to an embodiment of the present utility model;

[0035] Figure 7 It is Figure 6 Structural schematic diagram without installing the housing;

[0036] Figure 8 Structural schematic diagram of the tab and the connecting piece welded according to an embodiment of the present utility model.

[0037] Description of the reference numerals:

[0038] 1. Housing; 101. Terminal; 1011. Positive terminal; 1012. Negative terminal; 102. Through hole; 103. Explosion-proof valve; 2. Electrode group; 201. Tab; 2011. Body; 2012. Bent portion; 3. Connecting piece; 301. Terminal connecting portion; 302. Tab connecting portion; 3021. Notch; 3022. Sub-connecting portion; 303. Transition connecting portion; 4. Sealing plate. Detailed implementation manners

[0039] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0040] Aiming at the problems in the related art that the connection manner between the connecting piece and the tab is complex and occupies more internal space of the battery cell, the present utility model provides a battery cell and a battery pack.

[0041] The following combines Figures 1 to 8 to describe the embodiments of the present utility model.

[0042] According to the embodiments of the present utility model, on the one hand, as Figures 1 to 8 shown, a battery cell is provided, including: a housing 1, a pole group 2 and a connecting piece 3.

[0043] Specifically, a pole post 101 is integrally formed inside the housing 1; the pole group 2 is disposed inside the housing 1 and is provided with a tab 201, the tab 201 is disposed in a staggered manner with the pole post 101, the tab 201 includes a body 2011 connected to the pole group 2 and a bent portion 2012 bent from the end of the body 2011 toward one side; the connecting piece 3 is disposed inside the housing 1 and on the pole group 2 for connecting the pole post 101 and the tab 201, and the connecting piece 3 is fixed in the space defined by the body 2011 and the bent portion 2012 and is in contact with the lower surface of the bent portion 2012.

[0044] In this embodiment, the terminal post 101 is integrated on the housing 1, indicating that the housing 1 in this embodiment is of an integrally formed structure. In this way, the gaps on the housing 1 can be reduced, the dust and water protection level of the battery cell and the structural strength of the housing 1 itself can be improved. In addition, in this embodiment, the terminal post 101 and the tab 201 are arranged in a staggered manner, making use of the space in the length direction inside the housing 1. Compared with the existing connection piece 3 and the tab 201 both arranged along the axial direction of the terminal post 101, the internal space of the housing 1 occupied by the connection piece 3 and the tab 201 in the height direction of the housing 1 in the connected state is reduced, improving the utilization rate of the internal space of the housing 1. Furthermore, more energy can be stored by the battery cell with the same volume. Secondly, the tab 201 is connected to the connection piece 3 through the bending portion 2012, which can reduce the operation difficulty of connecting the tab 201 and the connection piece 3 and also reduce the occupation of the internal space of the housing 1 by the two in the connected state. Further, making the connection piece 3 fit the lower surface of the bending portion 2012 helps to ensure good electrical contact between the connection piece 3 and the tab 201, reduce the contact resistance, and improve the electrical conductivity of the battery cell.

[0045] It should be noted that the tab 201 and the electrode group 2 in this embodiment are integrally formed. In addition, the width direction and the height direction of the housing 1 in this embodiment are Figure 2 consistent with the directions shown in

[0046] It should be supplemented that the battery cell in this embodiment can be, but is not limited to, a square battery.

[0047] According to an embodiment of the present invention, as Figure 3 shown, the body 2011 of the tab 201 is perpendicular to the bending portion 2012. In this embodiment, the body 2011 of the tab 201 and the bending portion 2012 of the tab 201 are perpendicular to each other, which can make the structure of the tab 201 in the housing 1 more compact, optimize the internal space of the housing 1, and improve the energy density of the battery cell.

[0048] In order to improve the structural strength of the tab 201 itself, in a specific embodiment, the body 2011 and the bending portion 2012 are integrally formed, and a transition fillet is provided at the connection between the body 2011 and the bending portion 2012.

[0049] According to an embodiment of the present invention, as Figure 3As shown, the height of the main body 2011 is adapted to the thickness of the connecting piece 3. In this embodiment, the height of the main body 2011 in the tab 201 is adapted to the thickness of the connecting piece 3. On the one hand, the lower surface of the bending part 2012 can be closely attached to the connecting piece 3. In this way, not only can the connection stability between the two be enhanced, but also the contact resistance can be reduced, and the transmission efficiency of the current between the tab 201 and the terminal 101 can be improved. On the other hand, it can make the structure of the connecting piece 3 and the tab 201 more compact in the connected state, reducing the unnecessary occupation of the internal space of the housing 1.

[0050] According to an embodiment of the present invention, as Figure 3 and Figure 7 shown, the connecting piece 3 includes a terminal connecting part 301 connected to the terminal 101 and a tab connecting part 302 connected to the tab 201. A transition connecting part 303 is formed between the tab connecting part 302 and the terminal connecting part 301. It can be understood that since the tab 201 and the terminal 101 in this embodiment are arranged in a staggered manner, the connecting piece 3 is divided into the terminal connecting part 301 and the tab connecting part 302, which can make the position of the connecting piece 3 adapt to the positions of the tab 201 and the terminal 101, so that the tab 201 and the terminal 101 can be connected, realizing the smooth flow of current between the tab 201 and the terminal 101. In addition, by forming a transition connecting part 303 between the tab connecting part 302 and the terminal connecting part 301, the stress concentration phenomenon between the tab connecting part 302 and the terminal connecting part 301 can be avoided, ensuring the connection strength between the two.

[0051] It should be noted that since the connection part between the tab 201 and the electrode group 2 is higher than other positions of the electrode group 2, the position of the tab connecting part 302 on the electrode group 2 needs to be adjusted adaptively, that is, along the height direction of the housing 1, the position of the tab connecting part 302 is higher than the position of the terminal connecting part 301.

[0052] According to an embodiment of the present invention, as Figures 2 to 8As shown, a pair of connecting tabs 3 are provided on the electrode group 2 at intervals along its length direction. On opposite sides of each connecting tab 3, electrode tabs 201 are respectively provided. The electrode tabs 201 on opposite sides are respectively located on opposite sides of the electrode tab connecting portion 302 along the width direction of the electrode group 2, and their respective bent portions 2012 are bent and extended towards each other. It should be noted that since the electrode posts 101 on the housing 1 are divided into a positive electrode post 1011 and a negative electrode post 1012, and the electrode tabs 201 on the electrode group 2 are divided into positive electrode tabs and negative electrode tabs, by providing a pair of connecting tabs 3 on the electrode group 2, not only can the positive electrode post 1011 be connected to the negative electrode tab, but also the negative electrode post 1012 can be connected to the negative electrode tab. In this way, the stable transmission of current between the electrode tab 201 and the electrode post 101 can be ensured, and the problem of poor contact can be reduced. Secondly, by arranging the pair of connecting tabs 3 at intervals, the short-circuit between the positive electrode post 1011 and the negative electrode post 1012 can be avoided, improving the safety of using the battery cell. Furthermore, by making the electrode tabs 201 on opposite sides be respectively located on opposite sides of the electrode tab connecting portion 302 along the width direction of the electrode group 2, this design makes the internal structure of the battery cell more compact, thereby improving the space utilization rate inside the housing 1.

[0053] It should be noted that in this embodiment, the length direction of the electrode group 2 is the same as the length direction of the housing 1, the width direction of the electrode group 2 is the same as the width direction of the housing 1, and both the length direction and the width direction of the electrode group 2 are Figure 2 consistent with the directions shown in

[0054] It should be additionally noted that when the battery cell in this embodiment is a square battery, the positive electrode post 1011 and the negative electrode post 1012 on the square battery are usually arranged at intervals on the same side of the battery cell. Therefore, in order to further reduce the volume of the battery cell, in a specific embodiment, the positive electrode post 1011 and the negative electrode post 1012 are arranged at intervals on the same side of the housing 1, and the electrode tabs 201 on the electrode group 2 and the electrode tab connecting portion 302 in the connecting tab 3 are both located between the positive electrode post 1011 and the negative electrode post 1012.

[0055] According to an embodiment of the present invention, as Figure 3 shown, there is a gap between the ends of the bent portions 2012 on opposite sides that are close to each other. It can be understood that compared with stacking the bent portions 2012 of the two electrode tabs 201 on one connecting tab 3 together, in this embodiment, leaving a gap between the ends of the bent portions 2012 on opposite sides that are close to each other can reduce the thickness when the two electrode tabs 201 are in a connected state with one connecting tab 3, that is, reduce the occupation of the internal space of the housing 1 and improve the energy density of the battery cell.

[0056] According to an embodiment of the present invention, as Figure 2 、 Figure 4 and Figure 8As shown, a notch 3021 extending along the length direction of the pole group 2 is provided on the tab connecting portion 302. The notch 3021 divides the tab connecting portion 302 into two sub-connecting portions 3022. The two sub-connecting portions 3022 correspond to a pair of tabs 201 one by one, and are respectively welded to the lower surface of the corresponding bent portion 2012. It should be noted that since the welding method between the bent portion 2012 and the connecting piece 3 can adopt ultrasonic welding, compared with taking the tab connecting portion 302 as a whole, in this embodiment, the notch 3021 is used to divide the tab connecting portion 302 into two sub-connecting portions 3022, which can avoid the influence of the vibration generated during the ultrasonic welding process on the entire tab connecting portion 302, and ensure the stability and quality of the welding of each sub-connecting portion 3022 to the corresponding tab 201.

[0057] In a specific embodiment, a pair of tabs 201 pass through the notch 3021. The pair of tabs 201 and the two sub-connecting portions 3022 are arranged in one-to-one correspondence. The bent portions 2012 of the two tabs 201 are respectively attached to the upper surfaces of the corresponding sub-connecting portions 3022.

[0058] According to an embodiment of the present invention, two through holes 102 are provided on the housing 1. The two through holes 102 and the two tab connecting portions 302 are arranged in one-to-one correspondence. A sealing plate 4 is provided on the through hole 102. In this embodiment, by providing the through hole 102 corresponding to the tab connecting portion 302 on the housing 1, an appropriate operating space can be provided for the operator, so that the operator can complete the operation of bending the bent portion 2012 towards the connecting piece 3 and the operation of welding the lower surface of the bent portion 2012 to the connecting piece 3. Secondly, by providing the sealing plate 4 on the through hole 102, the sealing performance of the housing 1 can be improved, and the possibility of external impurities entering the battery cell can be reduced.

[0059] According to an embodiment of the present invention, as Figure 1 and Figure 8 shown, an explosion-proof valve 103 is further provided on the housing 1. The explosion-proof valve 103 is located between the two through holes 102. In this embodiment, by providing the explosion-proof valve 103 on the housing 1, it can be automatically opened when the internal pressure of the battery cell exceeds the safety threshold, release the internal gas, and prevent the battery cell from exploding due to excessive internal pressure. Secondly, by arranging the explosion-proof valve 103 between the two through holes 102, the space on the surface of the housing 1 can be fully utilized, making the overall structure of the battery cell more compact.

[0060] According to an embodiment of the present utility model, on the other hand, a battery pack is further provided, including: a plurality of the above-mentioned battery cells. By adopting the above-mentioned battery cells, the battery pack of this embodiment can improve its own space utilization rate, so that without changing its own volume, it can improve its own energy density, extend its own usage time or reduce the charging frequency. In addition, the battery pack of this embodiment has all the advantages of the above-mentioned battery cells, which will not be elaborated here.

[0061] Although the embodiments of the present utility model have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present utility model, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A battery cell, characterized in that, Comprising: A housing with a terminal post integrally provided inside. An electrode assembly disposed inside the housing and provided with electrode tabs, the electrode tabs being arranged in a staggered manner with respect to the terminal post, the electrode tabs including a body connected to the electrode assembly and a bent portion bent from an end of the body toward one side. A connecting piece disposed inside the housing and located on the electrode assembly for connecting the terminal post and the electrode tab, the connecting piece being fixed within the space defined by the body and the bent portion and being in contact with the lower surface of the bent portion. The body is perpendicular to the bent portion. The height of the body is adapted to the thickness of the connecting piece. The connecting piece includes a terminal post connecting portion connected to the terminal post and an electrode tab connecting portion connected to the electrode tab, and a transition connecting portion is formed between the electrode tab connecting portion and the terminal post connecting portion. A pair of the connecting pieces are provided on the electrode assembly at intervals along its length direction, the electrode tabs are respectively provided on opposite sides of each connecting piece, the electrode tabs on opposite sides are respectively located on opposite sides of the electrode tab connecting portion along the width direction of the electrode assembly, and their respective bent portions are bent and extended toward each other.

2. The battery cell according to claim 1, wherein, A gap is left between the ends of the bent portions on opposite sides that are close to each other.

3. The battery cell according to claim 2, wherein The electrode tab connecting portion is provided with a notch extending along the length direction of the electrode assembly, the notch divides the electrode tab connecting portion into two sub-connecting portions, the two sub-connecting portions correspond to the pair of electrode tabs one by one, and are respectively welded to the lower surface of the corresponding bent portion.

4. The battery cell according to claim 1, characterized in that Two through holes are provided on the housing, the two through holes are arranged corresponding to the two electrode tab connecting portions one by one, and a sealing plate is provided on the through holes.

5. The battery cell according to claim 4, wherein An explosion-proof valve is further provided on the housing, and the explosion-proof valve is located between the two through holes.

6. A battery pack, characterized in that, Comprising: A plurality of battery cells according to any one of claims 1 to 5.

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