CN217485594U - Battery and power consumption device - Google Patents

Abstract

The application discloses battery and power consumption device. The battery includes a first battery cell and a plurality of second battery cells. The first battery cell has a capacity of K1 and a volume of V1. The plurality of second battery cells and the first battery cells are stacked, the capacity of the second battery cells is K2, the volume of the second battery cells is V2, V2 is larger than V1, and K1/K2 is not less than 0.9 and not more than 1.1. The size of the first battery monomer is smaller than that of the second battery monomer, the first battery monomer and the second battery monomer are stacked and arranged, the first battery monomer is inserted into a gap of the second battery monomer, the first battery monomer and the second battery monomer are tightly arranged, and the utilization rate of the internal space of the battery is improved. The capacity of the first battery cell and the capacity of the second battery cell meet the condition that K1/K2 is more than or equal to 0.9 and less than or equal to 1.1, the capacity of the first battery cell is closer to the capacity of the second battery cell, the capacity difference between the first battery cell and the second battery cell is smaller, and the whole capacity and the energy exertion of the battery can be effectively guaranteed.

Description

Battery and power consumption device

Technical Field

The application belongs to the technical field of batteries, and particularly relates to a battery and an electric device.

Background

The battery cell is widely used in electronic devices such as a mobile phone, a notebook computer, a battery car, an electric airplane, an electric ship, an electric toy car, an electric toy ship, an electric toy airplane, an electric tool, and the like. The battery monomer can comprise a cadmium-nickel battery monomer, a hydrogen-nickel battery monomer, a lithium ion battery monomer, a secondary alkaline zinc-manganese battery monomer and the like.

The battery includes a plurality of battery cells to provide higher voltage and capacity for the powered device. In the development of battery technology, how to improve the performance of a battery cell is a research direction in battery technology.

SUMMERY OF THE UTILITY MODEL

The embodiment of the application provides a battery and power consumption device, can promote the utilization ratio of battery inner space, improves battery volume energy density.

In a first aspect, an embodiment of the present application provides a battery, which includes a first battery cell and a plurality of second battery cells. The capacity of the first battery cell is K1, and the volume of the first battery cell is V1. A plurality of second battery cells are stacked with the first battery cells. The capacity of the second battery cell is K2, the volume of the second battery cell is V2, and V2 is greater than V1. Wherein K1 and K2 satisfy: K1/K2 is more than or equal to 0.9 and less than or equal to 1.1.

In the above-mentioned technique, the free volume of first battery is less than the free volume of second battery, and first battery is single with the in-process that the second battery piled up the setting, can make first battery insert locate the space that the second battery formed to make first battery closely arrange with the second battery, promote the utilization ratio of battery inner space. The capacity of the first battery cell and the capacity of the second battery cell meet the condition that K1/K2 is more than or equal to 0.9 and less than or equal to 1.1, the capacity of the first battery cell is closer to the capacity of the second battery cell, and the capacity difference between the first battery cell and the second battery cell is smaller, so that the whole capacity and the energy exertion of the battery can be effectively ensured.

In some embodiments, K1 and K2 satisfy: K1/K2 is more than or equal to 0.95 and less than or equal to 1.05.

In the above scheme, the capacity of the first battery cell is approximately equal to the capacity of the second battery cell, and the capacity difference between the first battery cell and the second battery cell can be further reduced, so that the overall capacity and energy exertion of the battery are further improved.

In some embodiments, V1 and V2 satisfy: 0.2< V1/V2< 1.

In the scheme, the volume of the first battery cell and the volume of the second battery cell meet 0.2< V1/V2<1, and the utilization rate of the internal space of the battery can be effectively improved and the volume energy density of the battery can be improved by arranging the first battery cell and the second battery cell in a combined manner, wherein the volumes of the first battery cell and the second battery cell are different in size; and can be with the free volume of first battery and the free volume control of second battery in reasonable within range, avoid the free volume of first battery to differ too big the meeting and lead to making the degree of difficulty to increase with the free volume of second battery.

In some embodiments, the capacity retention rate of the second battery cell is higher than the capacity retention rate of the first battery cell in a state of-10 ℃.

In the above scheme, compared with the first battery monomer, the low-temperature performance of the second battery monomer is superior to that of the first battery monomer, the second battery monomer is more suitable for being used in an environment with lower temperature, and when the second battery monomer is arranged, the second battery monomer can be correspondingly arranged at a position with lower temperature or faster heat dissipation.

In some embodiments, the capacity retention rate of the second battery cell is higher than the capacity retention rate of the first battery cell in a state of 45 ℃.

In the above scheme, compared with the second battery monomer, the high-temperature performance of the first battery monomer is superior to that of the second battery monomer, the first battery monomer is more suitable for being used in an environment with higher temperature, and when the first battery monomer is arranged, the first battery monomer can be correspondingly arranged at a position with higher temperature or slower heat dissipation.

In some embodiments, the critical temperature of the second battery cell thermal runaway is higher than the critical temperature of the first battery cell thermal runaway.

In the above scheme, the thermal runaway critical temperature of the first battery monomer is different from that of the second battery monomer, so that the situation that the thermal runaway of the first battery monomer and the thermal runaway of the second battery monomer occur at the same time at the same temperature is avoided, and the safety performance of the battery is improved.

In some embodiments, the first battery cell number is a, the second battery cell number is b, and a and b satisfy: 0< a/b is less than or equal to 200.

In the scheme, the number of the first battery monomers and the number of the second battery monomers meet the condition that a/b is more than 0 and less than or equal to 200, so that the energy density of the battery and the energy exertion in the environment with lower temperature can be ensured.

In some embodiments, the first battery cell and the second battery cell are both cylindrical battery cells.

In this scheme, the shape of the first battery cell and the shape of the second battery cell can be flexibly selected to be square or other shapes.

In some embodiments, the battery includes a first battery row including a plurality of first battery cells sequentially arranged in a first direction, and a second battery row including a plurality of second battery cells sequentially arranged in the first direction. And a gap is arranged between the adjacent second battery cells. The first battery row and the second battery row are arranged in a staggered mode along the first direction, so that at least part of the first battery cell is accommodated in the corresponding gap.

In the scheme, the first battery cell and the second battery cell are arranged in a close arrangement in a first direction and a second direction in an alternating and staggered manner, so that the volume energy density of the battery is improved.

In some embodiments, the first battery row has a first centerline that passes through a central axis of the first plurality of battery cells. The second battery row has a second center line passing through the central axes of the plurality of second battery cells. The first center line and the second center line are arranged along a second direction, and the second direction is perpendicular to the first direction. The distance between the first center line and the second center line along the second direction is D, the radius of the first battery cell is R, the radius of the second battery cell is R, D, R and R satisfy: R-R is not more than D < R + R.

In this scheme, a part of first battery monomer can insert to between two second battery monomers to utilize the space between two second battery monomers, thereby improve the inside space utilization of battery.

In some embodiments, the second battery row is provided in plurality, and the plurality of second battery rows are arranged in a second direction perpendicular to the first direction.

In the scheme, the number of the first battery rows and the number of the second battery rows, the number of the first single batteries in the first battery rows and the number of the second single batteries in the second battery rows can be flexibly selected, and the batteries can be closely arranged to improve the volume energy density of the batteries as much as possible.

In a second aspect, the present application provides an electric device, where the electric device includes a battery as described above, and the battery is used for providing electric energy.

In this scheme, the battery that adopts includes first battery monomer and second battery monomer, and the free volume of first battery is less than the free volume of second battery, and first battery monomer piles up the in-process that sets up with second battery monomer, can make first battery monomer insert and locate in the space that second battery monomer formed to make first battery monomer and the inseparable range of second battery monomer, promote the utilization ratio of battery inner space. The capacity of the first battery cell and the capacity of the second battery cell meet the condition that K1/K2 is more than or equal to 0.9 and less than or equal to 1.1, the capacity of the first battery cell is closer to the capacity of the second battery cell, and the capacity difference between the first battery cell and the second battery cell is smaller, so that the whole capacity and the energy exertion of the battery can be effectively ensured.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be briefly described below, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a vehicle provided in some embodiments of the present application;

fig. 2 is an exploded schematic view of a battery provided in accordance with some embodiments of the present application;

FIG. 3 is a schematic diagram of a battery according to further embodiments of the present application;

FIG. 4 is a schematic diagram of a battery according to another embodiment of the present application;

fig. 5 is a schematic structural diagram of a battery according to further embodiments of the present application;

fig. 6 is a schematic diagram of a battery according to still other embodiments of the present application;

fig. 7 is a schematic structural diagram of a battery according to further embodiments of the present application;

fig. 8 is a schematic structural diagram of a battery according to still other embodiments of the present application;

fig. 9 is a schematic structural diagram of a battery according to still other embodiments of the present application.

The reference numbers illustrate:

1. a vehicle; 2. a battery; 211. a first battery cell; 212. a second battery cell; 22. a box body; 221. a first tank portion; 222. a second tank portion; 223. an accommodating space; 23. a first battery row; 231. a first centerline; 24. a second battery row; 241. a second centerline; 25. a void; 3. a controller; 4. a motor; 5. a battery module; x, a first direction; y, a second direction.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are merely used to more clearly illustrate the technical solutions of the present application, and therefore are only examples, and the protection scope of the present application is not limited thereby.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof, in the description and claims of this application and the description of the above figures are intended to cover non-exclusive inclusions.

In the description of the embodiments of the present application, the technical terms "first", "second", and the like are used only for distinguishing different objects, and are not to be construed as indicating or implying relative importance or implicitly indicating the number, specific order, or primary-secondary relationship of the technical features indicated. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is only one kind of association relationship describing an associated object, and means that three relationships may exist, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), and similarly, "plural sets" refers to two or more (including two), and "plural pieces" refers to two or more (including two).

In the description of the embodiments of the present application, the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate orientations and positional relationships that are based on the orientations and positional relationships shown in the drawings, and are used for convenience in describing the embodiments of the present application and for simplification of the description, but do not indicate or imply that the device or element referred to must have a specific orientation, be configured and operated in a specific orientation, and thus, should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless otherwise explicitly specified or limited, the terms "mounted," "connected," "fixed," and the like are to be construed broadly, e.g., as meaning fixedly connected, detachably connected, or integrated; mechanical connection or electrical connection is also possible; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

In this application, the battery cell may include a lithium ion secondary battery cell, a lithium ion primary battery cell, a lithium sulfur battery cell, a sodium lithium ion battery cell, a sodium ion battery cell, or a magnesium ion battery cell, and the embodiment of the present application is not limited thereto. The battery cell may be a cylinder, a flat body, a rectangular parallelepiped, or other shapes, which is not limited in the embodiments of the present application. The battery cells are generally divided into three types in an encapsulation manner: the single battery of cylindricality battery, square battery monomer and laminate polymer battery monomer, this application embodiment is to this also not limited.

Reference to a battery in embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charge or discharge of battery cells.

The battery cell includes an electrode assembly including a positive electrode tab, a negative electrode tab, and a separator, and an electrolyte. The battery cell mainly depends on metal ions to move between the positive pole piece and the negative pole piece to work. The positive pole piece comprises a positive current collector and a positive active substance layer, and the positive active substance layer is coated on the surface of the positive current collector; the positive current collector comprises a positive current collecting part and a positive electrode lug protruding out of the positive current collecting part, the positive current collecting part is coated with a positive active substance layer, and at least part of the positive electrode lug is not coated with the positive active substance layer. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, the positive electrode active material layer includes a positive electrode active material, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative pole piece comprises a negative pole current collector and a negative pole active substance layer, and the negative pole active substance layer is coated on the surface of the negative pole current collector; the negative current collector comprises a negative current collecting part and a negative electrode lug protruding out of the negative current collecting part, the negative current collecting part is coated with a negative electrode active substance layer, and at least part of the negative electrode lug is not coated with the negative electrode active substance layer. The material of the negative electrode current collector may be copper, the negative electrode active material layer includes a negative electrode active material, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the high current can be passed through without fusing, a plurality of positive electrode tabs are stacked together, and a plurality of negative electrode tabs are stacked together. The material of the spacer may be PP (polypropylene) or PE (polyethylene). In addition, the electrode assembly may have a winding structure or a lamination structure, and the embodiment of the present application is not limited thereto.

The battery usually includes a plurality of battery cells, unnecessary gaps are usually generated in the arrangement process of the battery cells, especially in the cylindrical battery cells, a large number of gaps are formed at the periphery of the cylindrical battery cells and cannot be utilized, and the utilization rate of the internal space of the battery is caused.

The inventors tried to put some small-sized battery cells into the gaps formed between the battery cells to utilize the gaps between the battery cells.

However, the inventors found that the capacity of two cells having different sizes is different, which makes the balance management of the two cells difficult, and the cell having a smaller capacity reaches the cut-off voltage in advance due to the short plate effect, which results in a lower capacity and energy to be actually exerted by the cell.

In view of this, an embodiment of the present application provides a battery, which includes a first battery cell and a plurality of second battery cells. The capacity of the first battery cell is K1, and the volume of the first battery cell is V1. A plurality of second battery cells are stacked with the first battery cells. The capacity of the second battery cell is K2, the volume of the second battery cell is V2, and V2 is larger than V1. K1 and K2 satisfy: K1/K2 is more than or equal to 0.9 and less than or equal to 1.1. In the technical scheme of this application embodiment, the free volume of first battery is less than the free volume of second battery, and the in-process that first battery monomer and second battery monomer piled up the setting can make first battery monomer insert and locate the space that second battery monomer formed to make first battery monomer and the inseparable range of second battery monomer, promote the utilization ratio of battery inner space. The capacity of the first battery cell and the capacity of the second battery cell meet the condition that K1/K2 is more than or equal to 0.9 and less than or equal to 1.1, the capacity of the first battery cell is closer to the capacity of the second battery cell, and the capacity difference between the first battery cell and the second battery cell is smaller, so that the whole capacity and the energy exertion of the battery can be effectively ensured, and the energy density and the cycle life of the battery are improved.

The battery described in the embodiment of the present application is suitable for various electric devices using the battery.

The electric device can be a vehicle, a mobile phone, a portable device, a notebook computer, a ship, a spacecraft, an electric toy, an electric tool and the like. The vehicle can be a fuel oil vehicle, a gas vehicle or a new energy vehicle, and the new energy vehicle can be a pure electric vehicle, a hybrid electric vehicle or a range-extended vehicle and the like; spacecraft include aircraft, rockets, space shuttles, and spacecraft, among others; electric toys include stationary or mobile electric toys, such as game machines, electric car toys, electric ship toys, electric airplane toys, and the like; the electric power tools include metal cutting electric power tools, grinding electric power tools, assembly electric power tools, and electric power tools for railways, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, electric impact drills, concrete vibrators, and electric planers. The embodiment of the present application does not particularly limit the above power utilization apparatus.

For convenience of explanation, the following embodiments will be described with an electric device as an example of a vehicle.

Fig. 1 is a schematic structural diagram of a vehicle according to some embodiments of the present application.

As shown in fig. 1, a battery 2 is provided inside a vehicle 1, and the battery 2 may be provided at the bottom or the head or the tail of the vehicle 1. The battery 2 may be used for power supply of the vehicle 1, and for example, the battery 2 may serve as an operation power source of the vehicle 1.

The vehicle 1 may further comprise a controller 3 and a motor 4, the controller 3 being adapted to control the battery 2 to power the motor 4, e.g. for start-up, navigation and operational power demands while driving of the vehicle 1.

In some embodiments of the present application, the battery 2 may be used not only as an operating power source of the vehicle 1, but also as a driving power source of the vehicle 1, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1.

Fig. 2 is an exploded view of a battery provided in some embodiments of the present application.

As shown in fig. 2, the battery 2 includes a case 22 and a battery cell (not shown in fig. 2), and the battery cell 21 is accommodated in the case 22.

The case 22 is used to accommodate the battery cells, and the case 22 may have various structures. In some embodiments, the casing 22 may include a first casing portion 221 and a second casing portion 222, the first casing portion 221 and the second casing portion 222 cover each other, and the first casing portion 221 and the second casing portion 222 together define a receiving space 223 for receiving the battery cells. The second casing part 222 may be a hollow structure with one open end, the first casing part 221 is a plate-shaped structure, and the first casing part 221 covers the open side of the second casing part 222 to form the casing 22 with the accommodating space 223; the first casing part 221 and the second casing part 222 may be hollow structures with one side opened, and the opened side of the first casing part 221 may cover the opened side of the second casing part 222 to form the casing 22 having the accommodating space 223. Of course, the first and second casing portions 221, 222 may be various shapes, such as a cylinder, a rectangular parallelepiped, or the like.

In order to improve the sealing property after the first casing portion 221 and the second casing portion 222 are connected, a sealing member, such as a sealant or a gasket, may be provided between the first casing portion 221 and the second casing portion 222.

Assuming that the first casing portion 221 covers the top of the second casing portion 222, the first casing portion 221 may also be referred to as an upper casing cover, and the second casing portion 222 may also be referred to as a lower casing 22.

In the battery 2, a plurality of battery cells are provided. The plurality of battery monomers can be connected in series or in parallel or in series-parallel, and the series-parallel refers to that the plurality of battery monomers are connected in series or in parallel. The plurality of battery cells can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery cells is accommodated in the box body 22; of course, a plurality of battery cells may be connected in series, in parallel, or in series-parallel to form the battery module 5, and a plurality of battery modules 5 may be connected in series, in parallel, or in series-parallel to form a whole, and may be accommodated in the box 22.

Fig. 3 is a schematic structural diagram of a battery according to another embodiment of the present application. Fig. 4 is a schematic structural diagram of a battery according to another embodiment of the present application.

As shown in fig. 3 to 7, the present embodiment provides a battery including a first battery cell 211 and a plurality of second battery cells 212. The capacity of the first battery cell 211 is K1, and the volume of the first battery cell 211 is V1. The plurality of second battery cells 212 are stacked with the first battery cells 211. The capacity of the second battery cell 212 is K2, the volume of the second battery cell 212 is V2, and V2 is greater than V1. Wherein K1 and K2 satisfy: K1/K2 is more than or equal to 0.9 and less than or equal to 1.1.

One or more first battery cells 211 may be provided.

The present embodiment does not limit the manner in which the first battery cell 211 and the second battery cell 212 are stacked. For example, the plurality of second battery cells 212 may be arranged in an array, and the first battery cell 211 may be disposed in a gap formed by the arrangement of the plurality of second battery cells 212.

The present embodiment does not limit the shapes of the first battery cell 211 and the second battery cell 212. For example, the first battery cell 211 may be a cylindrical battery cell, a square battery cell, or another shape of battery cell, and the second battery cell 212 may be a cylindrical battery cell, a square battery cell, or another shape of battery cell.

In the above-mentioned technology, the volume of the first battery cell 211 is smaller than the volume of the second battery cell 212, and in the process of stacking the first battery cell 211 and the second battery cell 212, the first battery cell 211 can be inserted into the gap 25 formed by the second battery cell 212, so that the first battery cell 211 and the second battery cell 212 are tightly arranged, and the utilization rate of the internal space of the battery is improved. The capacity of the first battery cell 211 and the capacity of the second battery cell 212 satisfy 0.9-K1/K2-1.1, the capacity of the first battery cell 211 is closer to the capacity of the second battery cell 212, and the capacity difference between the two is smaller, so that the overall capacity and energy exertion of the battery can be effectively ensured, and the energy density and cycle performance of the battery are improved.

The capacity K1 of the first battery cell 211 may be measured in the following manner: in an environment of 25 ℃, the first battery cell 211 is discharged at a rate of 0.33C from the upper limit voltage to a capacity exhibited by the lower limit voltage being cut off, that is, the capacity K1.

The capacity K2 of the second battery cell 212 may be measured as follows: in an environment of 25 ℃, the second battery cell 212 is discharged at a rate of 0.33C from the upper limit voltage to the capacity obtained by cutting off the lower limit voltage, that is, the capacity K2.

Alternatively, in the case that the volume of the first battery cell 211 is smaller than the volume of the second battery cell 212, in order to make the capacity of the first battery cell 211 close to the capacity of the second battery cell 212, the volumetric energy density of the first battery cell 211 should be greater than or equal to the volumetric energy density of the second battery cell 212.

The difference in volumetric energy density between the first battery cell 211 and the second battery cell 212 can be achieved by selecting different types of battery cells.

Alternatively, the first battery cell 211 and the second battery cell 212 may be a lithium ion battery cell, a sodium ion battery cell, a lithium metal battery cell, a lithium ion air battery cell, a fuel battery cell, or other kinds of battery cells. The first battery cell 211 and the second battery cell 212 may be different in kind, for example, the first battery cell 211 is a lithium ion battery cell, and the second battery cell 212 is a sodium ion battery cell. The first battery cell 211 and the second battery cell 212 may be of the same type, for example, the first battery cell 211 and the second battery cell 212 are both lithium ion battery cells.

Optionally, the lithium ion battery cell includes, but is not limited to, a lithium nickel cobalt manganese system battery cell, a lithium iron phosphate system battery cell, a lithium iron manganese phosphate system battery cell, a lithium vanadium iron phosphate system battery cell, a lithium vanadium lithium phosphate system battery cell, a lithium cobalt oxide system battery cell, a lithium nickel system battery cell, a lithium manganese rich system battery cell, a lithium nickel cobalt aluminum system battery cell, a lithium manganese system battery cell, and the like.

The sodium ion battery includes, but is not limited to, a prussian blue battery cell, a metal oxide battery cell, and the like.

The present application is not limited thereto as long as the battery cells have different volumetric energy densities, similar capacities, and different volumes.

In some embodiments, K1 and K2 satisfy: K1/K2 is more than or equal to 0.95 and less than or equal to 1.05.

In the above-described embodiment, the capacity of the first battery cell 211 is approximately equal to the capacity of the second battery cell 212, and the capacity difference between the first battery cell 211 and the second battery cell 212 can be further reduced, so as to further improve the overall capacity and energy utilization of the battery.

In some embodiments, V1 and V2 satisfy: 0.2< V1/V2< 1.

In the above scheme, the volume of the first battery cell 211 and the volume of the second battery cell 212 satisfy 0.2< V1/V2<1, and the first battery cell 211 and the second battery cell 212 with different volumes are arranged in a combined manner, so that the utilization rate of the internal space of the battery can be effectively improved, and the volume energy density of the battery can be improved.

Optionally, V1 and V2 satisfy: 0.3< V1/V2<0.95, so that the difference between the volume of the first battery cell 211 and the volume of the second battery cell 212 is reduced, and the processing and manufacturing difficulty of the battery can be reduced.

Optionally, V1 and V2 satisfy: 0.35< V1/V2<0.9, the difference between the volume of the first single battery cell 211 and the volume of the second single battery cell 212 is further reduced, the volume of the first single battery cell 211 and the volume of the second single battery cell 212 are controlled within a reasonable range, and the problem that the manufacturing difficulty is increased due to the fact that the difference between the volumes of the first single battery cell 211 and the second single battery cell 212 is too large is solved.

In some embodiments, the capacity retention rate of the second battery cell 212 is higher than the capacity retention rate of the first battery cell 211 in a state of-10 ℃.

The capacity retention rate in the state of-10 ℃ can be measured according to the following procedure: and (3) standing the battery cell in a full-charge state in a thermostat at 25 ℃ for 2h, discharging at a rate of 0.33C until the lower limit cut-off voltage is reached, and recording the unit capacity C1 of the battery cell. The cell was left to stand in a fully charged state in an incubator at-10 ℃ for 2 hours, discharged using a rate of 0.33C until the lower cut-off voltage was reached, and the capacity C2 of the cell at-10 ℃ was recorded and the capacity retention at-10 ℃ was recorded for C2/C1.

In the above solution, compared with the first battery cell 211, the low temperature performance of the second battery cell 212 is better than that of the first battery cell 211, the second battery cell 212 is more suitable for being used in an environment with a lower temperature, and when being set, the second battery cell 212 can be correspondingly set at a position with a lower temperature or a position with a faster heat dissipation.

In some embodiments, the capacity retention rate of the second battery cell 212 is higher than the capacity retention rate of the first battery cell 211 in a state of 45 ℃.

The capacity retention in the state at 45 ℃ can be measured according to the following procedure: and (3) standing the battery cell in a full-charge state in a thermostat at 25 ℃ for 2h, discharging at a rate of 0.33C until the lower limit cut-off voltage is reached, and recording the unit capacity C1 of the battery cell. The cells were left to stand in a fully charged state and at 45 ℃ for 2h, discharged using a rate of 0.33C until the lower cut-off voltage was reached, and the capacity of the cells at 45 ℃ was recorded as C3, and the capacity retention at 45 ℃ was recorded as C3/C1.

In the above scheme, compared with the first battery cell 211, the high-temperature performance of the second battery cell 212 is better than that of the first battery cell 211, the second battery cell 212 is more suitable for being used in an environment with a higher temperature, and when the battery pack is arranged, the second battery cell 212 can be correspondingly arranged at a position with a higher temperature or a position with a slower heat dissipation.

Optionally, when the first battery cell 211 and the second battery cell 212 are arranged, a first region and a second region are divided inside a box of the battery, a heat exchange coefficient in the first region is smaller than a heat exchange coefficient in the second region, the first region is mainly used for arranging the first battery cell 211, and the second region is mainly used for arranging the second battery cell 212.

Optionally, the first battery cell 211 is a lithium ion battery, the second battery cell 212 is a sodium ion battery, and by utilizing the characteristic that the low-temperature performance of the sodium ion battery is superior to that of the lithium ion battery, the lithium ion battery is arranged in a first area with a small heat exchange coefficient, and the sodium ion battery is arranged in a second area with a large heat exchange coefficient, so that the high-temperature and low-temperature performance of the first battery cell 211 and the high-temperature and low-temperature performance of the second battery cell 212 can be considered, and the service life of the battery can be prolonged.

Optionally, the second region is disposed on at least one side of the first region, or the second region surrounds the first region.

Illustratively, the second region is located at the periphery, bottom, or other thermally insulating weak area of the cell with a special function device/means, and the first region is located at the center of the cell.

The weak heat-preservation area is also a relatively weak structural strength area, the sodium ion battery has the advantage of good low-temperature performance, and the safety performance of the sodium ion battery such as needling resistance and extrusion resistance is also superior to that of the lithium ion battery, so that the second battery monomer 212 is the sodium ion battery, the service performance of the battery can be improved, and the safety performance of the battery can also be improved.

Optionally, the second region may also be partially disposed in the center of the battery, and a portion of the second battery cell 212 may also be selectively disposed in the center of the battery, which is not limited in this application.

Optionally, the number of the first battery cells 211 in the first region is 10% to 100%; the number of the second battery cells 212 in the second region is 5% to 100%. At least one of the first battery cell 211 and the second battery cell 212 is flexibly arranged in both the first region and the second region, so that the space utilization rate in the battery is improved as much as possible, and the volume capacity density of the battery is improved.

In some embodiments, the critical temperature of the thermal runaway of the second battery cell 212 is higher than the critical temperature of the thermal runaway of the first battery cell 211.

The first battery cell 211 and the second battery cell 212 are subjected to a heating abuse test, the fully charged first battery cell 211 and the fully charged second battery cell 212 are respectively and fixedly placed in a high-temperature box through a clamp, the first battery cell 211 and the second battery cell 212 are respectively heated from room temperature to 100 ℃ at a heating speed of 5 ℃/min and are kept for 1 hour, the first battery cell 211 and the second battery cell 212 are respectively heated at a heating speed of 5 ℃/min again, the temperature of the first battery cell 211 and the temperature of the second battery cell 212 are respectively increased by 5 ℃ every time, the temperature is kept for 30 minutes until the first battery cell 211 and the second battery cell 212 respectively start to smoke and fire, at the moment, the first battery cell 211 and the second battery cell 212 are subjected to thermal runaway, and critical temperatures of the first battery cell 211 and the second battery cell 212 are respectively recorded.

Alternatively, the difference between the critical temperature of the thermal runaway of the second battery cell 212 and the critical temperature of the thermal runaway of the first battery cell 211 is greater than 1 ℃.

In the above scheme, the critical temperature of thermal runaway of the first battery cell 211 and the second battery cell 212 is different, so that the situation that the thermal runaway of the first battery cell 211 and the thermal runaway of the second battery cell 212 occur at the same temperature is avoided, and the safety performance of the battery is improved.

Alternatively, the difference between the critical temperature of the thermal runaway of the second battery cell 212 and the critical temperature of the thermal runaway of the first battery cell 211 is greater than 5 ℃. So as to further reduce the possibility of thermal runaway occurring in the first battery cell 211 and the second battery cell 212 at the same time, and improve the safety performance of the battery.

In some embodiments, the number of the first battery cells 211 is a, the number of the second battery cells 212 is b, and a and b satisfy: 0< a/b ≤ 200.

a and b are both positive integers greater than or equal to 1.

Optionally, a and b satisfy: 0.01< a/b is less than or equal to 180.

Optionally, a and b satisfy: 0.1< a/b < 150.

In the present embodiment, the ratio of the number of the first battery cells 211 to the number of the second battery cells 212 is limited, so that the energy density of the battery and the energy exertion in the low-temperature environment can be ensured.

In some embodiments, the first battery cell 211 and the second battery cell 212 are both cylindrical battery cells.

The diameter of the first battery cell 211 is phi 1, the diameter of the second battery cell 212 is phi 2, and the diameter of the first battery cell 211 and the diameter of the second battery cell 212 satisfy: 0.2< phi 1/phi 2<1, and further 0.3< phi 1/phi 2< 0.9.

Optionally, the diameter of the first battery cell 211 is Φ 1, and Φ 1 satisfies: 1cm < phi 1<20 cm.

Further, phi 1 satisfies: 2cm < phi 1<18 cm. Further, phi 1 satisfies: 3cm < phi 1<10 cm.

In this embodiment, when the diameter of the first battery cell 211 and the diameter of the second battery cell 212 satisfy the above requirements, the utilization rate of the internal space of the battery can be improved.

Fig. 5 is a schematic structural diagram of a battery according to further embodiments of the present disclosure. Fig. 6 is a schematic structural diagram of a battery according to further embodiments of the present application. Fig. 7 is a schematic structural diagram of a battery according to further embodiments of the present application.

As shown in fig. 5 to 7, optionally, the shapes of the first battery cell 211 and the second battery cell 212 may also be flexibly selected to be square or other shapes.

When the first battery cell 211 and the second battery cell 212 are square batteries, the sizes of the first battery cell 211 and the second battery cell 212 in any two directions of the first direction X, the second direction Y, and the third direction are fixed. For example, the dimensions of the first battery cell 211 and the second battery cell 212 in the first direction X and the third direction Y are fixed, the dimension of the first battery cell 211 in the second direction Y is Y1, and the dimensions of the second battery cell 212 in the second direction Y are Y2, Y1 and Y2: 0.2< y1/y2<1, alternatively, 0.3< y1/y2<0.95, further, 0.35< y1/y2< 0.9.

Through setting up first battery monomer 211 and second battery monomer 212 as the size difference that only has a direction, can closely arrange first battery monomer 211 and second battery monomer 212, effectively reach the effect that promotes battery volume energy density.

In some embodiments, the battery includes a first battery row 23 and a second battery row 24, the first battery row 23 includes a plurality of first battery cells 211 sequentially arranged along the first direction X, and the second battery row 24 includes a plurality of second battery cells 212 sequentially arranged along the first direction X. A gap 25 is provided between the adjacent second battery cells 212. The first battery row 23 and the second battery row 24 are disposed with a shift in the first direction X such that at least a portion of the first battery cells 211 are accommodated in the corresponding void 25.

In this embodiment, the first battery cells 211 and the second battery cells 212 are arranged in an alternating and staggered manner in the first direction X and the second direction Y to increase the volumetric energy density of the battery.

In some embodiments, the first battery row 23 has a first center line 231, and the first center line 231 passes through a center axis of the plurality of first battery cells 211. The second battery row 24 has a second center line 241, and the second center line 241 passes through the central axis of the plurality of second battery cells 212. The first center line 231 and the second center line 241 are disposed along a second direction Y, which is perpendicular to the first direction X. The distance between the first center line 231 and the second center line 241 along the second direction Y is D, the radius of the first battery cell 211 is R, and the radii of the second battery cell 212 are R, D, R and R satisfy: R-R is not more than D < R + R. Optionally, 0cm ≦ D <40 cm. Further, D is more than or equal to 0.5cm and less than 30 cm.

Fig. 8 is a schematic structural diagram of a battery according to still other embodiments of the present disclosure. Fig. 9 is a schematic structural diagram of a battery according to still other embodiments of the present disclosure.

Illustratively, a cylindrical battery cell is taken as an example. As described in the above embodiments, 0.2< phi 1/phi 2<1, i.e., 0.2< R/R < 1. When the second cells are arranged in the form as shown in fig. 8, the first battery cell 211 cannot satisfy the filling of the voids 25 between the second battery cells 212, when D satisfies 0.5 × (R + R) ≦ D ≦ R + R. When the second battery cells are arranged in the form shown in fig. 9, there are two situations, in the first situation, when R/R is less than or equal to 0.414, the first battery cell 211 is completely located in the gap 25 of the second battery cell 212, and at this time, D satisfies that R-R is less than or equal to D and less than or equal to R + R, which is beneficial for stacking the first battery cell 211 and the second battery cell 212, and the gap 25 is relatively uniform; in the second case, when D is 0.414< R/R <1, the maximum critical value is that the first battery cell 211 and the second battery cell 212 have the same diameter, i.e., D ≦ R.

Therefore, in combination with the above arrangement, D satisfies: R-R is not more than D and is less than R + R, so that the first battery monomer 211 and the second battery monomer 212 can be tightly stacked as much as possible, the gap 25 is reduced, and the space utilization rate in the battery is improved to the greatest extent.

In this embodiment, a portion of the first battery cell 211 may be inserted between the two second battery cells 212 to utilize the gap 25 between the two second battery cells 212, thereby improving the space utilization inside the battery.

In some embodiments, the second battery row 24 is provided in plurality, and the plurality of second battery rows 24 are arranged in the second direction Y perpendicular to the first direction X.

Optionally, at least one side of each first battery row 23 or each second battery row 24 is provided with one first battery row 23 or one second battery row 24.

In this embodiment, the number of the first battery rows 23 and the number of the second battery rows 24, the number of the first battery cells 211 in the first battery row 23, and the number of the second battery cells 212 in the second battery row 24 can be flexibly selected, as long as the first battery cells and the second battery cells can be closely arranged, so as to increase the volume energy density of the battery as much as possible.

The battery provided by the embodiment of the application needs to perform the following tests when the first battery cell 211 and the second battery cell 212 are arranged:

1. testing the capacity of the battery monomer: the initial discharge capacity of the battery monomer is as follows: under the environment of 25 ℃, each battery cell starts to discharge from the upper limit voltage at a rate of 0.33C until the lower limit voltage is cut off to exert the capacity.

2. Testing the volume energy density of the battery: the initial discharge capacity of the battery is multiplied by the discharge voltage platform/the total volume of the battery;

wherein, the initial discharge capacity of the battery is as follows: the battery in the environment of 25 ℃ is discharged from the upper limit voltage to the capacity exerted by the lower limit voltage cut-off at a rate of 0.33C.

The discharge voltage plateau is defined as the average discharge voltage of the battery in the 25 ℃ environment from the upper limit voltage to the lower limit voltage cutoff when the battery is discharged at the rate of 0.33C.

3. Capacity retention ratio of battery at-10 ℃: the rated capacity was first tested, and the battery was left to stand in a 25 ℃ incubator for 2 hours in a fully charged state, discharged using a rate of 0.33C until the lower limit cut-off voltage was reached, and the capacity C1 was recorded. The cell was then tested for-10 ℃ capacity, discharged at 0.33C rate until the lower cut-off voltage was reached, and the capacity C2, C2/C1, recorded as-10 ℃ capacity retention, in a fully charged state and left to stand in an incubator at-10 ℃ for 2 h.

4. The thermal spreading test of the battery comprises two test methods:

the method comprises the following steps: and testing whether a certain battery cell in the battery can spread to an adjacent battery cell after thermal runaway occurs due to heating. A test battery module formed by two or more battery monomers to be tested determines whether a heat insulation pad is added between the battery monomers and the thickness of the heat insulation pad according to specific scenes, and determines whether to start water circulation. And selecting a heating thermal runaway triggering method, such as a heating plate/heating sheet heating method, testing the full charge of the battery module, fixing the module by using a clamp, and attaching a heating sheet to one side surface of the first battery monomer with a larger area.

Connecting the heating sheet with a power supply, starting heating after a heating sheet power supply device is started, closing the heating sheet until thermal runaway of a first battery monomer occurs, and observing and recording the time when thermal runaway of a second adjacent battery monomer occurs; if the battery monomer which is out of control by touching the heat does not cause the adjacent battery monomer to be ignited or explode, judging that the heat spreading is realized, otherwise, judging that the heat spreading occurs.

The second method comprises the following steps: and testing whether a certain battery monomer in the battery can spread to an adjacent battery monomer after thermal runaway occurs due to needling. A test battery module formed by two or more battery monomers to be tested determines whether a heat insulation pad is added between the battery monomers and the thickness of the heat insulation pad according to specific scenes, and determines whether to start water circulation. And (4) fully charging the test battery module, and selecting two steel plate clamps with holes to fix the test battery module. Penetrating a high-temperature-resistant stainless steel needle (the needle angle cone angle is 20-60 degrees, the surface of the steel needle is smooth and clean, and is free of rust, oxide layers and oil stains) with the diameter of 3-8 mm from the direction perpendicular to the polar plates of the battery monomers to the first battery monomer at the speed of 0.1-40 mm/s, and observing and recording the time of thermal runaway of the adjacent second battery core; and judging that the thermal spreading is realized if the battery monomer which is out of control by touch heating does not cause the adjacent battery monomer to be ignited or explode, otherwise, judging that the thermal spreading occurs.

Table 1 shows the experimental data for the various groups of specific examples as follows:

TABLE 1

As can be seen from table 1, in examples 1 to 3, when the battery includes the first battery cell 211 and the second battery cell 212, and each parameter of the first battery cell 211 and the second battery cell 212 satisfies the range described in the above examples, the volumetric energy density and the capacity retention rate at-10 ℃ of the battery are high, and the result of the battery thermal spreading test is thermal spreading resistance; in example 4, the battery only includes a lithium ion battery cell, and although the capacity retention ratio of the battery is high at-10 ℃, the volumetric energy density of the battery is greatly reduced, and thermal spread occurs in a thermal spread test of the battery; in example 5, the battery includes only the sodium ion battery cell, and in this case, the capacity retention rate at-10 ℃ of the battery is greatly reduced although the volumetric energy density of the battery is high.

Therefore, the battery provided by the embodiment of the application has higher volumetric energy density and capacity retention rate, and the safety performance of the battery is superior to that of a battery formed by a traditional single battery monomer.

In a second aspect, the present application provides an electric device, where the electric device includes a battery as described above, and the battery is used for providing electric energy.

In this scheme, the battery that adopts includes first battery monomer 211 and second battery monomer 212, and the volume of first battery monomer 211 is less than the volume of second battery monomer 212, and first battery monomer 211 piles up the in-process that sets up with second battery monomer 212, can make first battery monomer 211 insert and locate in the space 25 that second battery monomer 212 formed to make first battery monomer 211 and the inseparable range of second battery monomer 212, promote the utilization ratio of battery inner space. The capacity of the first battery cell 211 and the capacity of the second battery cell 212 satisfy 0.9-K1/K2-1.1, the capacity of the first battery cell 211 is closer to the capacity of the second battery cell 212, and the capacity difference between the two is smaller, so that the overall capacity and energy exertion of the battery can be effectively ensured.

The powered device may be any of the aforementioned battery-powered devices or systems.

As shown in fig. 3 to 7, an embodiment of the present application provides a battery, which includes a first battery cell 211 and a plurality of second battery cells 212. The first battery cell 211 is a lithium ion battery, and the second battery cell 212 is a sodium ion battery.

The capacity of the first battery cell 211 is K1, and the volume of the first battery cell 211 is V1. The plurality of second battery cells 212 are stacked with the first battery cells 211. The capacity of the second battery cell 212 is K2, the volume of the second battery cell 212 is V2, V2 is greater than V1, and 0.35< V1/V2< 0.9. Wherein K1 and K2 satisfy: K1/K2 is more than or equal to 0.95 and less than or equal to 1.05.

The number of the first battery cells 211 is a, the number of the second battery cells 212 is b, and a and b satisfy: 0.1< a/b < 150.

The first battery cell 211 is divided into a first area with high temperature or slow heat dissipation and a second area with low temperature or fast heat dissipation in the box body, wherein the first area is mainly used for arranging the first battery cell 211, and the second area is mainly used for arranging the second battery cell 212.

So in the process of stacking the first battery monomer 211 and the second battery monomer 212, because the volume of the first battery monomer 211 is smaller than that of the second battery monomer 212, the first battery monomer 211 can be inserted into the gap 25 formed by the second battery monomer 212, so that the first battery monomer 211 and the second battery monomer 212 are tightly arranged, and the utilization rate of the internal space of the battery is improved. The capacity of the first battery cell 211 and the capacity of the second battery cell 212 satisfy 0.9-K1/K2-1.1, the capacity of the first battery cell 211 is closer to the capacity of the second battery cell 212, and the capacity difference between the two is smaller, so that the overall capacity and energy exertion of the battery can be effectively ensured.

As described above, only the specific embodiments of the present application are provided, and it can be clearly understood by those skilled in the art that, for convenience and brevity of description, the specific working processes of the system, the module and the unit described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again. It should be understood that the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the present application, and these modifications or substitutions should be covered within the scope of the present application.

Claims (12)

1. A battery, comprising:

a first battery cell having a capacity of K1 and a volume of V1;

a plurality of second battery cells stacked with the first battery cell, the second battery cell having a capacity of K2, the second battery cell having a volume of V2, V2 being greater than V1;

wherein K1 and K2 satisfy: K1/K2 is more than or equal to 0.9 and less than or equal to 1.1.

2. The battery of claim 1, wherein K1 and K2 satisfy: K1/K2 is more than or equal to 0.95 and less than or equal to 1.05.

3. The battery of claim 1, wherein V1 and V2 satisfy: 0.2< V1/V2< 1.

4. The battery of claim 1, wherein the second battery cell has a higher capacity retention than the first battery cell in a state of-10 ℃.

5. The battery of claim 1, wherein the capacity retention rate of the second battery cell is higher than the capacity retention rate of the first battery cell in a state of 45 ℃.

6. The battery of claim 1, wherein the critical temperature for thermal runaway of the second battery cell is higher than the critical temperature for thermal runaway of the first battery cell.

7. The battery according to claim 1, wherein the number of the first battery cells (1) is a, the number of the second battery cells is b, and a and b satisfy: 0< a/b is less than or equal to 200.

8. The battery according to claim 1, characterized in that the first battery cell (1) and the second battery cell are both cylindrical battery cells.

9. The battery according to claim 8, comprising a first battery row including a plurality of the first battery cells arranged in sequence along a first direction, and a second battery row including a plurality of the second battery cells arranged in sequence along the first direction;

gaps are formed between every two adjacent second battery monomers;

the first battery row and the second battery row are arranged in a staggered mode along the first direction, so that at least part of the first battery cell is accommodated in the corresponding gap.

10. The battery of claim 9, wherein the first row of batteries has a first centerline that passes through a central axis of a plurality of the first battery cells; the second battery row has a second center line passing through a central axis of the second plurality of battery cells;

the first centerline and the second centerline are disposed along a second direction, the second direction being perpendicular to the first direction;

the distance between the first center line and the second center line along the second direction is D, the radius of the first battery cell is R, and the radius of the second battery cell is R, D, R and R satisfy: R-R is not more than D and is less than R + R.

11. The battery according to claim 9, wherein the second battery row is provided in plurality, and a plurality of the second battery rows are arranged in a second direction perpendicular to the first direction.

12. An electrical consumer, characterized in that the consumer comprises a battery according to any of claims 1 to 11 for providing electrical energy.

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