CN114583406A

CN114583406A - Battery core, battery core module, power battery pack and vehicle

Info

Publication number: CN114583406A
Application number: CN202210344112.3A
Authority: CN
Inventors: 曾士哲
Original assignee: Weilai Automobile Technology Anhui Co Ltd
Current assignee: Weilai Automobile Technology Anhui Co Ltd
Priority date: 2022-03-31
Filing date: 2022-03-31
Publication date: 2022-06-03

Abstract

The invention relates to the technical field of power batteries, and particularly provides a battery cell, a battery cell module, a power battery pack and a vehicle, aiming at solving the problem of poor overcurrent capacity of the conventional long battery cell. The battery cell provided by the invention comprises: a pole core including a pole piece and a tab connected to the pole piece, the pole piece having long sides and short sides, the tab including a first tab connected to one of the short sides and a second tab connected to one of the long sides; the shell, it includes the casing and is connected to the first apron and the second apron at the both ends of casing respectively, is provided with utmost point post on the first apron, wherein, the pole piece sets up in the shell, first utmost point ear is connected with utmost point post electricity, and second utmost point ear is connected with the casing electricity to regard as electron circulation passageway with the help of the casing, thereby make second utmost point ear can be connected with the second apron electricity. The battery cell provided by the invention can greatly improve the overcurrent capacity of the battery cell and the energy density of the battery cell, and has the advantages of simple structure and low cost.

Description

Battery core, battery core module, power battery pack and vehicle

Technical Field

The invention relates to the technical field of power batteries, and particularly provides a battery core, a battery core module, a power battery pack and a vehicle.

Background

With the rapid development of the new energy automobile market, the power battery technology is also rapidly and iteratively upgraded, and the endurance mileage and the fast charging of the pure electric automobile are two focuses of close attention of consumers.

Among the existing power batteries, a 4680 large cylindrical battery of Tesla and a long blade battery of BYD are the mainstream technical routes. Compared with the prior art, the full-lug large cylindrical battery has obvious advantages in the aspects of energy density and quick charge, but the space utilization rate of the battery pack is lower than that of the blade battery. The space utilization rate of the long-blade battery pack is larger than that of the battery pack, and the positive lugs and the negative lugs connected with the long pole pieces are respectively distributed on the short sides in order to improve the space utilization rate. Fig. 1 is a schematic diagram of a current loop state of a long battery cell in the prior art during a charging process, as shown in fig. 1, when a conventional long battery cell 1' is charged, electrons in a positive plate enter a negative plate from left to right in an external circuit along a counterclockwise path in the figure to form a circuit loop. It can be seen from the figure that, in the process that electrons enter the negative plate from left to right, the current density is gradually reduced, the electrons are unevenly distributed in the negative plate, the overcurrent capacity of the negative plate is reduced, the charging capacity of the battery cell is greatly limited, usually only 2C, and the fast charging requirement of the whole vehicle cannot be met.

Disclosure of Invention

The present invention aims to solve or at least alleviate the above technical problems, i.e. at least solve the problem of poor current capacity of existing long cells.

In a first aspect, the present disclosure provides a cell, comprising: a pole core comprising a pole piece and a tab connected to the pole piece, the pole piece having long sides and short sides, the tab comprising a first tab connected to one of the short sides and a second tab connected to one of the long sides; the shell, it includes the casing and is connected to respectively the first apron and the second apron at the both ends of casing, be provided with utmost point post on the first apron, wherein, the utmost point core sets up in the shell, first utmost point ear with utmost point post electricity is connected, second utmost point ear with the casing electricity is connected, so that with the help of the casing is as electron circulation passageway, thereby makes second utmost point ear can with the second apron electricity is connected.

According to the battery cell provided by the invention, one of the first tab and the second tab is arranged on one long side of the pole piece, the tab is electrically connected with the shell, the shell is electrically connected with the second cover plate on the short side, the other of the first tab and the second tab is arranged on one short side of the pole piece, and the tab is electrically connected with the pole of the first cover plate, so that the tab connected to the long side and the second cover plate are used as an electron circulation channel through the shell, the pole is not required to be arranged on the long side, the space utilization rate of the battery cell is not reduced due to the improvement of overcurrent capacity, and the second cover plate on the short side is not required to be provided with the tab; in addition, the path of electrons entering the corresponding pole piece is greatly shortened due to the pole ear connected to the long side, so that the charging or discharging multiplying power of the battery cell can be improved in multiples; moreover, because the contact surface of the tab in the length direction of the pole piece is wider, the current density entering the corresponding pole piece can be uniformly distributed in the length direction, and the problem of non-uniform current density of the conventional battery cell is solved; finally, the structure of the battery cell can be simplified, and the number of structural components is reduced, so that the cost of the battery cell is reduced.

For the above battery cell, in some possible embodiments, the second tab is a positive tab or a negative tab.

The second tab in the present invention may be a positive tab or a negative tab. When the second tab is a positive tab, the discharge multiplying power of the corresponding battery cell can be multiplied; when the second tab is the negative tab, the charge multiplying power of the corresponding battery cell can be increased in multiples.

For the above-described cell, in some possible embodiments, the second tab is a full tab or a plurality of die-cut tabs.

It can be understood that, when the second tab is a positive tab and is a full tab, the longer the full tab is, the more uniformly the current density is distributed in the positive tab, the better the overcurrent capacity is, but the energy density of the cell is reduced to some extent (compared with the scheme adopting the die-cutting tab). Therefore, the length of the full tab can be determined based on the length of the pole piece, and the appropriate length is selected under the condition of considering both energy density and overcurrent capacity.

When the second utmost point ear is anodal ear and for cross cutting utmost point ear, the inside space utilization of electric core is higher, and utmost point ear weight proportion of occupying is less relatively, and the energy density of electric core is higher than the energy density of the electric core that adopts full utmost point ear.

Similarly, when the second tab is a negative tab, a full tab can be adopted, and a die-cut tab can also be adopted.

In some possible embodiments, the second tab is welded to the housing in the above-described battery cell.

It will be appreciated that the manner of welding may be ultrasonic welding, laser welding, a combination of ultrasonic and laser welding, or the like.

In some possible embodiments, for the battery cell described above, a connecting piece is further disposed in the casing, and the positive tab is connected to the casing by welding through the connecting piece.

Through setting up the connection piece, be favorable to second utmost point ear and the smooth and firm connection of casing, guarantee the stable performance of battery.

In some possible embodiments, the cross-sectional shape of the connecting piece is approximately "Ω" shape for the above-described cell.

By arranging the connecting piece to be approximately omega-shaped in cross section, when the connecting piece is connected above the second lug, one part of the second lug can penetrate into the connecting piece, so that the connection stability among the second lug, the connecting piece and the shell can be further improved.

For the battery cell described above, in some possible embodiments, when the second tab is a positive tab, the connecting sheet is made of aluminum, and/or the casing is made of aluminum.

For the battery cell described above, in some possible embodiments, when the second tab is a negative tab, the connecting sheet is made of copper, and/or the casing is made of steel or copper.

For the above-mentioned battery cell, in some possible embodiments, the pole pieces include a positive pole piece and a negative pole piece, and the positive pole piece and the negative pole piece are arranged in a laminated manner.

In a second aspect, the present invention further provides a battery cell module, where the battery cell module includes a package frame, and a plurality of battery cells according to any one of the above technical solutions packaged in the package frame.

In a third aspect, the invention further provides a power battery pack, and the power battery pack is configured with the battery cell module according to the technical scheme.

In a fourth aspect, the invention further provides a vehicle, which is characterized in that the vehicle is provided with the power battery pack of the technical scheme.

It is understood that the vehicle equipped with the power battery pack may be a pure electric vehicle or a hybrid vehicle.

Those skilled in the art can understand that, since the battery cell module, the power battery pack and the vehicle are configured with the battery cell, all technical effects of the battery cell are achieved, and are not described herein again.

Scheme 1. an electric core, characterized in that, the electric core includes:

a pole core comprising a pole piece and a tab connected to the pole piece, the pole piece having long sides and short sides, the tab comprising a first tab connected to one of the short sides and a second tab connected to one of the long sides;

a housing including a case and a first cover plate and a second cover plate respectively connected to both ends of the case, the first cover plate being provided with a pole,

wherein, the pole piece sets up in the shell, first utmost point ear with utmost point post electricity is connected, second utmost point ear with the casing electricity is connected, so that with the help of the casing is as electron circulation passageway, thereby makes second utmost point ear can with the second apron is connected electrically.

The battery cell according to the scheme 1, characterized in that the second tab is a positive tab or a negative tab.

The battery cell according to the scheme 2 is characterized in that the second tab is a full tab or a plurality of die-cut tabs.

The battery cell according to claim 3, wherein the second tab is welded to the casing.

The battery cell of the invention 5 is characterized in that a connecting sheet is further arranged in the shell, and the second pole lug is connected with the shell in a welding mode through the connecting sheet.

The battery cell of claim 6, wherein the cross-sectional shape of the connecting piece is approximately "Ω".

Scheme 7. the battery cell of scheme 5, wherein,

when the second tab is a positive tab, the connecting sheet is made of aluminum, and/or the shell is made of aluminum; alternatively, the first and second electrodes may be,

when the second tab is a negative tab, the connecting piece is made of copper, and/or the shell is made of steel or copper.

Scheme 8. the battery cell according to any one of schemes 1 to 7, wherein the pole pieces comprise positive pole pieces and negative pole pieces, and the positive pole pieces and the negative pole pieces are arranged in a laminated manner.

Scheme 9. a battery cell module, wherein the battery cell module includes a package frame, and a plurality of battery cells of any one of schemes 1 to 8 packaged in the package frame.

Scheme 10. a power battery package, characterized in that, power battery package disposes the electric core module of scheme 9.

The vehicle of the scheme 11 is characterized in that the vehicle is provided with the power battery pack of the scheme 10.

Drawings

Preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

fig. 1 is a schematic diagram of a current loop state of a long cell in a charging process in the prior art;

fig. 2 is a schematic structural diagram of a battery cell provided in embodiment 1 of the present invention;

FIG. 3 is a rear view of FIG. 2;

FIG. 4 is a sectional view taken along line A-A of FIG. 3;

fig. 5 is a schematic structural view of a pole core provided in embodiment 1 of the present invention;

FIG. 6 is a schematic structural view of a connecting sheet provided in embodiment 1 of the present invention;

fig. 7 is a schematic view of a connection structure between the Mylar film and the positioning plastic part according to embodiment 1 of the present invention;

fig. 8 is a schematic view of a connection structure of a tab and a connecting sheet according to embodiment 1 of the present invention;

FIG. 9 is an enlarged partial schematic view of FIG. 8;

fig. 10 is a schematic structural view of a first cover plate according to embodiment 1 of the present invention;

fig. 11 is a schematic structural view of a second cover plate according to embodiment 1 of the present invention;

fig. 12 is a schematic structural diagram of a battery cell provided in embodiment 1 of the present invention in a charging state;

fig. 13 is a schematic structural diagram of a battery cell according to embodiment 2 of the present invention;

fig. 14 is a schematic structural view of a pole piece provided in embodiment 2 of the present invention;

fig. 15 is a schematic view of a connection structure of a tab and a connecting sheet according to embodiment 2 of the present invention;

list of reference numerals:

1', existing long cells;

1. an electric core; 10. a housing; 11. a first cover plate; 110. a first pole column; 111. an explosion-proof valve; 12. a second cover plate; 120. a liquid injection hole; 121. a second pole; 122. an explosion-proof valve; 20. pole pieces; 21. a negative tab; 22. a positive tab; 23. a Mylar film; 24. positioning the plastic part; 30. and (7) connecting the sheets.

Detailed Description

First, it should be noted that the following embodiments are only for explaining the technical principle of the present invention, and are not intended to limit the scope of the present invention.

Furthermore, in the following detailed description, numerous specific details are set forth in order to provide a better understanding of the present invention. It will be understood by those skilled in the art that the present invention may be practiced without some of these specific details.

In the description of the present invention, the terms "upper", "lower", "left", "right", "top", "bottom", and the like, which indicate directions or positional relationships, are based on directions or positional relationships in practical use, and are used for convenience of description only, and do not indicate or imply that the apparatus to be protected must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the present invention, "not indicated" indicates that the corresponding structure is not illustrated but is illustrated in the drawings, and "not illustrated" indicates that the corresponding structure is not illustrated in the drawings.

The following describes a battery cell provided by the present invention with reference to the drawings.

Example 1

Referring to fig. 2 to 12, fig. 2 is a schematic structural diagram of a battery cell provided in embodiment 1 of the present invention; FIG. 3 is a rear view of FIG. 2; FIG. 4 is a sectional view taken along line A-A of FIG. 3; fig. 5 is a schematic structural view of a pole core provided in embodiment 1 of the present invention; FIG. 6 is a schematic structural view of a connecting sheet provided in embodiment 1 of the present invention; fig. 7 is a schematic view of a connection structure between the Mylar film and the positioning plastic part according to embodiment 1 of the present invention; fig. 8 is a schematic view of a connection structure of a tab and a connecting sheet according to embodiment 1 of the present invention; FIG. 9 is an enlarged partial schematic view of FIG. 8; fig. 10 is a schematic structural view of a first cover plate according to embodiment 1 of the present invention; fig. 11 is a schematic structural view of a second cover plate according to embodiment 1 of the present invention; fig. 12 is a schematic structural diagram of a battery cell provided in embodiment 1 of the present invention in a charging state.

The battery cell provided by the embodiment comprises a shell and a pole piece arranged in the shell.

Specifically, as shown in fig. 5, the pole core includes a pole piece 20 and a pole tab connected to the pole piece 20, and the pole piece 20 includes a positive pole piece and a negative pole piece, which are separated by a separator (not shown) to prevent short circuit. The positive plates and the negative plates in this embodiment are arranged in a lamination manner, and in general, the number of the negative plates is one more than that of the positive plates in order to improve the utilization rate of the plates in the battery cell 1. The positive plate and the negative plate are both provided with long sides and short sides, and the pole core in a laminated state is of a plate-shaped structure under the wrapping of the shell.

In the pole core, each positive plate is connected with a positive tab, and each negative plate is connected with a negative tab. The conventional positive electrode tab and the conventional negative electrode tab are respectively located at two ends of the battery cell in the length direction, namely two short sides in fig. 1. In this embodiment, the negative tab 21 is connected to the top long side of the negative tab and the positive tab 22 is connected to the right short side of the positive tab. More specifically, the negative electrode tab 21 in the present embodiment is a full tab, and the positive electrode tab 22 is a die-cut tab. The full tab does not need die cutting in the preparation process, and is generally subjected to strip processing after being coated and rolled. Compared with the die-cutting lug, the full lug has relatively better overcurrent capacity, better rate performance than the die-cutting lug, one less process for preparing the pole piece and lower manufacturing cost than the die-cutting lug.

Alternatively, the negative electrode tab in this embodiment may also adopt a plurality of die-cut tabs, and compared with the full tab, the die-cut tab needs to additionally add one die-cut process. When the negative pole ear adopts a plurality of cross cutting utmost point ears, the inside space utilization of electric core is higher, and utmost point ear weight accounts for than relatively less, and the energy density of electric core is higher than the electric core that adopts full utmost point ear when adopting cross cutting utmost point ear in the electric core of the same volume.

In addition, the negative tab may be connected to the bottom long side of the negative tab, and the positive tab may be connected to the left short side of the positive tab.

The shell is used for providing a fully-closed space for the pole core, and the pole core is arranged in the shell. The housing includes a hollow casing 10 with two open ends, and a first cover plate 11 (or referred to as a positive cover plate) and a second cover plate 12 (or referred to as a negative cover plate) respectively connected to the two ends of the casing 10. In the present embodiment, the first cover plate 11 is provided with a first pole post 110, which is electrically connected to the positive electrode tab 22.

The first cover plate 11 has a structure as shown in fig. 10, and is provided with a first pole column 110 as a terminal for connecting the battery cell 1 to an external circuit. The first cover plate 11 is further provided with an explosion-proof valve 111, the battery cell 1 can generate certain gas in the working process, the gas is discharged through the explosion-proof valve 111, and explosion caused by overhigh internal pressure of the battery cell 1 can be effectively prevented.

The second cover 12 is structured as shown in fig. 11, and the second cover 12 itself serves as a terminal for connection to an external circuit without providing a post since it does not need to be directly connected to the negative electrode tab 21. The second cover plate 12 is provided with a liquid injection hole 120, after the electrical core 1 is assembled, electrolyte is injected through the liquid injection hole 120, and a rubber plug (not shown) for plugging is further arranged at the liquid injection hole 120.

In this embodiment, the positive tab 22 that is located the right side minor face of utmost point core is connected with first utmost point post 110 electricity, the negative tab 21 that is located the long limit of top of utmost point core is connected with casing 10 electricity, casing 10's material is the high strength steel, make very thin steel casing, thickness is 0.1mm, the steel casing is connected as an organic whole structure with left second apron 12, so, electric core 1 is in the charging process, the electron channel that the electron that dissociates from the positive tab can be constructed with the help of casing 10 and second apron 12 arrives the negative pole piece fast, form the current return circuit, thereby promote electric core 1's the multiplying power that charges.

Further, in order to facilitate connection between the negative electrode tab 21 and the casing 10, in this embodiment, a connecting sheet 30 is further provided, and the negative electrode tab 21 is connected to the casing 10 through the connecting sheet 30, specifically, the negative electrode tab 21 and the connecting sheet 30 are welded to the casing 10, and preferably, the three are welded together by using a laser penetration welding technique. Referring to fig. 3, 4 and 6, the connecting sheet 30 is a strip structure with a cross section approximately in an "Ω" shape, and a plurality of through holes are formed in the strip structure, and the through holes are beneficial to achieving smooth welding of the negative electrode tab 21, the connecting sheet 30 and the casing 10, and reducing the weight of the battery core 1.

As shown in fig. 7 to 9, the pole core further includes a Mylar film 23 and a positioning plastic part 24 wrapped around the pole piece, the Mylar film 23 plays an insulating role to prevent short circuit inside the electric core 1, the positioning plastic part 24 is used for positioning in the process of wrapping the pole piece with the Mylar film 23, a strip-shaped via hole is formed in the middle of the positioning plastic part 24, and a strip-shaped negative pole piece penetrates through the strip-shaped via hole and then is connected to the connecting piece 30, and further welded to the housing 10. In this embodiment, the connecting sheet 30 is made of copper and has a thickness of 0.6 mm.

In this embodiment, since the negative electrode tab 21 is a full-tab, in order to further reduce the weight of the battery cell 1, only one short connecting piece 30 may be disposed at a position near to each of the two ends of the negative electrode tab 21, as shown in fig. 8.

The operation principle of the battery cell 1 provided in this embodiment is as shown in fig. 12, when the battery cell 1 is charged, the first terminal post 110 and the second cover plate 12 are respectively connected to an external circuit, electrons of the positive electrode plate sequentially enter the external circuit through the positive electrode tab 22 and the first terminal post 110, and after reaching the second cover plate 12, the electrons circulating in the external circuit reach the negative electrode tab 21 through the casing 10, and further uniformly enter the negative electrode plate from top to bottom through the negative electrode tab 21. In the process, because the path through which electrons flow from the negative electrode tab 21 to the negative electrode plate is short, and the contact surface between the negative electrode tab 21 and the negative electrode plate is large, the electrons can rapidly enter the negative electrode plate, so that the rapid charging capability of the battery cell 1 is improved. In the process, the current density of the charging current is basically consistent at all positions of the negative plate, so that the problem of uneven current density caused by long pole core length in the prior art is effectively solved.

It should be noted that, during the assembly process, the negative electrode tab 21 needs to be first subjected to an ultrasonic flattening process, then sleeved with the Mylar film 23 with the positioning plastic piece 24, and then subjected to a bending process, and then laser penetration welded with the housing 10 through the connecting piece 30. The positive tab 22 is also subjected to ultrasonic rubbing and leveling treatment, is directly welded with the first cover plate 11 after being bent, and is wrapped by a high-temperature-resistant insulating adhesive tape to prevent the metal part exposed and leaked from the positive electrode in the battery cell 1 from contacting with the shell 10 to cause a short circuit problem. And then fixing the Mylar film 23 by using an insulating adhesive tape, and fixing two ends of the Mylar film onto the plastic of the cover plate through hot melting. The first and

second cover plates

11 and 12 are then welded to the case 10 by continuous laser welding, thereby completing the assembly of the battery cell 1. After the assembled battery core 1 is baked, injected, formed, aged and secondarily replenished with liquid, the liquid injection hole 120 is plugged into a rubber plug for plugging, a sealing aluminum sheet is adopted for laser welding sealing, and then cleaning, coating and grading are carried out, so that the preparation of the battery core 1 is completed.

The experimental parameters of the battery cell in this embodiment may refer to table 1:

TABLE 1

Item	Unit of	Cell parameters
			Size of	mm	20700115
Type (B)	/	Lithium iron phosphate
			Capacity of	Ah	230
Weight (D)	kg	3.67
			Voltage of	V	3.2
Internal resistance of AC	mΩ	0.2
			Specific energy	Wh/kg	201
Capability of charging	/	5C

As can be seen from table 1, after the battery cell in the embodiment is adopted, the charging capability of the battery cell is increased in multiples, and the charging capability is greatly improved.

Example 2

The present embodiment is the same as embodiment 1 in technical concept, and all lies in that one of the tabs is placed on the long side of the pole core and electrically connected with the casing 10, so as to use the casing 10 as an electron flow channel, thereby keeping the current density of electrons during the flow process uniform. The difference between this embodiment and embodiment 1 is that the second tab in this embodiment is the positive tab 22, and when the positive tab 22 is placed on the long side of the pole core, the discharge rate of the battery cell 1 can be effectively improved.

Specifically, referring to fig. 13 and 14, the positive tab 22 in the present embodiment employs a plurality of die-cut tabs, and the plurality of die-cut tabs are uniformly arranged on the top long side of the positive plate and are welded together with the positive plate, specifically, ultrasonic welding or laser welding may be employed. The negative electrode tab 21 is a die-cut tab, and is connected to the right short side of the negative electrode sheet by ultrasonic welding or laser welding. The welding mark of ultrasonic welding (ultrasonic welding) is smoother, the multilayer tabs can be welded together, and subsequent laser welding is facilitated due to the smooth surface of the tab.

In this embodiment, the negative tab 21 is connected to the short side, and the negative tab 21 needs to be electrically connected to the post, so that the second cover plate 12 in this embodiment is provided with a second post 121, as shown in fig. 13, the negative tab 21 is electrically connected to the second post 121. The second cover plate 12 is also provided with an explosion-proof valve 122 for discharging gas generated during the operation of the battery.

It is understood that, since the positive tab 22 in the present embodiment is electrically connected to the housing 10, no post is required to be disposed on the first cover plate 11.

In this embodiment, the negative tab 21 located on the right short side of the pole piece is electrically connected to the second pole post 121, the positive tab 22 located on the top long side of the pole piece is electrically connected to the casing 10, the casing 10 is made of aluminum and has a thickness of 0.3mm, and the connecting piece 30 in this embodiment is also made of aluminum and has a thickness of 0.8 mm. Comparing fig. 2 and 13, the laser welding (not labeled) of the positive tab 22 and the case 10 in this embodiment is different from the laser welding of the negative tab 21 and the case 10 in embodiment 1, and the welding of the multi-tab structure and the case 10 in this embodiment is a multi-pass welding. In this way, in the process of discharging after the battery cell 1 is connected to a load, electrons dissociated from the negative electrode tab firstly enter an external circuit through the second electrode post 121, the electrons of the external circuit can quickly reach each positive electrode tab 22 through an electron channel constructed by the casing 10 and the first cover plate 11, and the electrons uniformly reach the positive electrode tab from top to bottom through each positive electrode tab 22. In the process, because the path of the electrons entering the positive plate from the positive lug 22 is short, and the positive lug 22 is uniformly distributed on the long side of the positive plate, the electrons can rapidly enter the positive plate, and the density of the current in the process is basically consistent at each position of the positive plate, so that the problem of nonuniform current density due to long length of the pole core in the prior art is effectively solved, and the quick discharge capacity of the cell 1 is improved.

Alternatively, the positive electrode tab 22 in the present embodiment may also be a full tab. In addition, the positive tab 22 may be connected to the bottom long side of the positive tab, and the negative tab 21 may also be connected to the left short side of the negative tab.

It should be noted that, since the positive electrode tab 22 in this embodiment uses a plurality of die-cut tabs, the length of the connecting piece 30 is longer than that in embodiment 1, and the length of the connecting piece 30 is equivalent to the distance between the two outermost positive electrode tabs 22, as shown in fig. 15, the structure of the connecting piece 30 in this embodiment is the same as that of the connecting piece 30 in embodiment 1.

The experimental parameters of the battery cell in this embodiment can be referred to in table 2

TABLE 2

Item	Unit of	Cell parameters
			Size of	mm	950080
Type (B)	/	High nickel ternary
			Capacity of	Ah	60
Weight(s)	kg	0.995
			Voltage of	V	3.65
Internal resistance of AC	mΩ	0.35
			Specific energy	Wh/kg	220
Discharge capacity	/	10C

It can be seen from table 2 that owing to connect a plurality of anodal ears on the long limit of the top of anodal piece for among the electron circulation process, can conduct to each anodal ear uniformly via the casing, and then get into anodal piece fast with the shortest distance, thereby promote the discharge capacity of electric core, compare with the discharge capacity of current electric core, the multiplying power cost that discharges increases.

It should be noted that the numerical values in the above examples are only exemplary and should not be construed as limiting the scope of the present invention, and those skilled in the art can change the numerical values in the above examples within a reasonable range as needed.

The embodiment of the invention also provides a battery cell module, which is composed of a plurality of battery cells and a packaging frame for packaging the battery cells, and the packaging frame is used as a unified boundary of the plurality of battery cells to realize connection with an external circuit.

The embodiment of the invention also provides a power battery pack, which comprises one or more battery cell modules, a Battery Management System (BMS), a thermal management system and the like, wherein the battery cell modules in the battery pack are connected in series, parallel and the like. It can be understood that a plurality of electric cores in the electric core module can contain the quick charge electric core in embodiment 1 and the quick discharge electric core in embodiment 2 simultaneously, and the quick charge electric core and the quick discharge electric core can compromise quick charge performance and quick discharge performance through the electric core module that the cluster parallel connection is constituteed, and then effectively promote the performance of power battery package.

So far, the technical solutions of the present invention have been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of the present invention is obviously not limited to these specific embodiments. Equivalent changes or substitutions of related technical features can be made by those skilled in the art without departing from the principle of the invention, and the technical scheme after the changes or substitutions can fall into the protection scope of the invention.

Claims

1. A battery cell, comprising:

a shell which comprises a shell body, a first cover plate and a second cover plate which are respectively connected to the two ends of the shell body, wherein the first cover plate is provided with a pole column,

2. The electrical core of claim 1, wherein the second tab is a positive tab or a negative tab.

3. The cell of claim 2, wherein the second tab is a full tab or a plurality of die cut tabs.

4. The cell of claim 3, wherein the second tab is welded to the casing.

5. The battery cell of claim 4, wherein a connecting piece is further disposed in the casing, and the second tab is welded to the casing via the connecting piece.

6. The cell of claim 5, wherein the cross-sectional shape of the tab is approximately "Ω" shaped.

7. The cell of claim 5, wherein,

8. The cell of any one of claims 1 to 7, wherein the pole pieces comprise positive pole pieces and negative pole pieces, and the positive pole pieces and the negative pole pieces are arranged in a laminated manner.

9. A cell module, characterized in that the cell module comprises an encapsulation frame, and a plurality of cells of any of claims 1 to 8 encapsulated within the encapsulation frame.

10. A power battery pack, characterized in that, the power battery pack is provided with the battery cell module of claim 9.