CN217182205U

CN217182205U - Electrode assembly of battery, battery monomer, battery and electric equipment

Info

Publication number: CN217182205U
Application number: CN202220720891.8U
Authority: CN
Inventors: 雷美娜; 林真; 李伟
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2022-03-30
Filing date: 2022-03-30
Publication date: 2022-08-12
Anticipated expiration: 2032-03-30

Abstract

The embodiment of the application discloses an electrode assembly of a battery, a battery monomer, the battery and electric equipment, wherein the electrode assembly comprises a positive pole piece, a negative pole piece and an isolating membrane, and the isolating membrane is arranged between the positive pole piece and the negative pole piece; the electrode assembly further comprises a sampling structure, the sampling structure is clamped between the positive pole piece and the isolating membrane, and/or between the negative pole piece and the isolating membrane, and the sampling structure is used for monitoring internal information of the battery. The electrode assembly, the single battery, the battery and the electric equipment can realize monitoring of the internal information of the battery by the sampling structure.

Description

Electrode assembly of battery, battery monomer, battery and electric equipment

Technical Field

The present application relates to the field of battery technology, and more particularly, to an electrode assembly of a battery, a battery cell, a battery, and an electric device.

Background

With the development of power battery technology and the arrival of the electric era, people put forward higher and higher demands on the safety, reliability and intelligent degree of a power battery system, and the requirements are that various parameter changes in the use process of the battery can be monitored in real time in multiple dimensions.

SUMMERY OF THE UTILITY MODEL

The application provides an electrode subassembly, battery monomer, battery and consumer of battery can realize the monitoring of the internal information of sampling structure to the battery.

In a first aspect, there is provided an electrode assembly of a battery, the electrode assembly including: the separator is arranged between the positive pole piece and the negative pole piece; the electrode assembly further includes a sampling structure interposed between the positive electrode tab and the separator, and/or between the negative electrode tab and the separator, so as to acquire internal information of the battery.

In this embodiment, the sampling structure is sandwiched between the positive electrode plate and the isolation film, and/or between the negative electrode plate and the isolation film, so that the internal information of the battery can be monitored by the sampling structure.

In addition, the electrode assembly of the embodiment can be compatible with the manufacturing process of the existing pole piece and isolation film because the sampling structure is arranged between the positive pole piece and the isolation film and/or between the negative pole piece and the isolation film, and the structures of the pole piece and the isolation film do not need to be changed.

In one possible implementation, the electrode assembly is in a stacked structure of a multi-layered arrangement.

In this embodiment, since the sampling structure is disposed between the positive electrode tab and the separator, and/or between the negative electrode tab and the separator, it is possible to achieve comprehensive monitoring of internal information of a battery having an electrode assembly in a multilayer laminated structure.

In one possible implementation, the sampling structure at least partially covers a non-edge region of the electrode assembly.

In this embodiment, locating the sampling structure in a non-edge region of the electrode assembly facilitates fixing the sampling structure.

In one possible implementation, the laminate structure is a wound structure wound a plurality of turns, and the sampling structure is provided in the electrode assembly of at least one turn of the wound structure, the at least one turn excluding the innermost turn and the outermost turn of the plurality of turns.

In this embodiment, for the electrode assembly of the winding structure, by disposing the sampling structure in the electrode assembly of at least one turn except for the innermost turn and the outermost turn, it is advantageous to fix the sampling structure by interlayer binding force.

In one possible implementation, the laminate structure is a stacked multi-layer laminate structure, and the sampling structure is disposed in the electrode assembly that is not the outermost layer.

In this embodiment, for the electrode assembly of the lamination stack, by disposing the sampling structure in the electrode assembly that is not the outermost layer, it is advantageous to fix the sampling structure by the interlayer binding force.

In one possible implementation, the sampling structure includes a fiber structure including an optical fiber and a plurality of fiber sensors inscribed on the optical fiber.

In the embodiment, the optical fiber sensor has the characteristics of small size, flexibility, electromagnetic insensitivity, high sensitivity, corrosion resistance, rich functions and the like, so that the method for monitoring the internal information of the battery by using the optical fiber sensor becomes a very reliable mode.

And the internal information of the battery monitored by the optical fiber sensor is transmitted to a demodulation unit outside the battery through the optical fiber, so that the internal information of the battery can be analyzed.

Further, in this embodiment, by engraving a plurality of optical fiber sensors on one optical fiber, various information of different portions inside the battery can be monitored.

In one possible implementation, the plurality of fiber sensors includes at least one of a single-mode bragg grating sensor, a multi-mode bragg grating sensor, a tilted bragg grating sensor, and a micro-structured grating sensor.

In the embodiment, the electrode assembly monitors the internal information of the battery by using the Bragg grating sensor, and has universality.

In one possible implementation, the length of the fiber sensor ranges between 0.1cm and 10 cm.

In the embodiment, the length of the optical fiber sensor is set between 0.1cm and 10cm, so that the optical signal is not lost, and the monitoring on a micro size can be realized.

In one possible implementation, the fiber optic sensor is 1cm in length.

In this embodiment, setting the length of the fiber optic sensor to 1cm can meet the size and space monitoring requirements of most electrode assemblies.

In one possible implementation, the diameter of the fiber ranges between 25um to 250 um.

In the embodiment, the diameter of the optical fiber is set between 25-250um, so that the optical signal transmission is not lost, and the size and space monitoring requirements of most electrode assemblies can be met.

In one possible implementation, the fiber has a diameter of 120 um.

In this embodiment, setting the diameter of the optical fiber to 120um, which is closer to the interlayer gap of the electrode assembly, allows the coupling of the optical fiber to the electrode assembly without increasing the thickness of the electrode assembly.

In one possible implementation, the internal information of the battery includes at least one of temperature, pressure, strain, concentration of anions and cations, turbidity of the electrolyte, composition of gas, aging degree of the electrolyte, gas content, swelling force, interface state, and reaction rate.

In this embodiment, the sampling structure may monitor the above-mentioned various information of the battery, which is beneficial to improving the performance of the battery.

In a second aspect, a battery cell is provided, where the battery cell includes a case and the electrode assembly in the first aspect and any one of the possible implementations of the first aspect, and the case is configured to accommodate the electrode assembly.

In this embodiment, an electrode assembly having a sampling structure is disposed in the battery cell, so that the sampling structure can monitor internal information of the battery cell.

In a possible implementation, the sampling structure is a fiber structure, and the housing is provided with a through hole for guiding the optical fiber in the fiber structure to the outside of the housing.

In this embodiment, the optical fiber has the characteristics of small volume, light weight, no source, pressure resistance, corrosion resistance and electromagnetic interference resistance, so that monitoring the internal information of the battery by using the optical fiber structure becomes a very reliable mode.

In this embodiment, through the through hole formed in the housing of the battery cell, the internal information of the battery monitored by the optical fiber sensor can be transmitted to the demodulation unit outside the battery cell through the optical fiber, so that the internal information of the battery cell can be analyzed.

In one possible implementation, the housing includes a housing and a cover plate, the through hole being provided in the cover plate.

In this embodiment, the through hole for guiding the optical fiber is provided on the cover plate, so that the optical fiber can penetrate out from the cover plate to the outer side of the battery cell, which is beneficial to the process packaging of the battery cell.

In one possible implementation, the electrode assembly is provided with a tab, and the cap plate is provided with an electrode terminal, with which the tab is electrically connected.

In this embodiment, the cover plate is provided with an electrode terminal and a through hole for guiding the optical fiber, so that the optical fiber can extend in the same direction as the tab, thereby facilitating the process packaging of the battery cell.

In one possible implementation, the electrode assembly is provided with a positive electrode tab and a negative electrode tab at a side facing the cover plate, the cover plate is provided with a positive electrode terminal and a negative electrode terminal, the positive electrode tab is electrically connected with the positive electrode terminal, and the negative electrode tab is electrically connected with the negative electrode terminal; the through hole is closer to the negative electrode terminal than to the positive electrode terminal.

In general, a liquid injection hole is provided in addition to an electrode terminal on a lid plate of a battery cell, and the liquid injection hole is generally located closer to a positive electrode terminal.

In one possible implementation, the angle between the optical fiber and the vertical direction of the cover plate when extending to the through hole ranges between 0 ° and 90 °.

In the embodiment, the angle between the optical fiber and the vertical direction of the cover plate when the optical fiber extends to the through hole is set between 0 degree and 90 degrees, so that the optical fiber can be prevented from being damaged due to overlarge angle.

In one possible implementation, the angle between the optical fiber when extending to the through hole and the vertical direction is 30 °.

In this embodiment, the angle from the perpendicular direction of the cover plate when the optical fiber extends to the through hole is set to 30 °, so that damage to the optical fiber due to an excessively large angle can be avoided.

In one possible implementation, the size of the through hole ranges between 1mm and 5 mm.

In the embodiment, the size of the through hole is set to be 1-5 mm, so that drilling and packaging are facilitated.

In one possible implementation, the size of the through hole is 2 mm.

In this embodiment, the size of the through hole is set to 2mm, which facilitates drilling and packaging.

In one possible implementation, the through hole and the optical fiber led out from the through hole are sealed by glue.

In the embodiment, the through hole and the optical fiber led out from the through hole are sealed by glue, so that the sealing performance of the battery cell can be improved, and the safety of the battery cell is improved.

In one possible implementation, the glue is epoxy resin, polyacrylic acid, ultraviolet curing glue or modified epoxy resin.

In the embodiment, the through hole is sealed by the ultraviolet curing adhesive, so that the through hole is corrosion-resistant, swelling-resistant and good in compatibility with the electrolyte.

In a third aspect, a battery is provided, which includes the battery cell as in the second aspect and any two possible implementation manners thereof.

In a fourth aspect, there is provided an electrical device comprising: the battery of the third aspect, the battery is for providing power to an electric device.

Drawings

Fig. 1 is a schematic structural diagram of a vehicle according to an embodiment of the present application.

Fig. 2 is a schematic structural diagram of a battery disclosed in an embodiment of the present application.

Fig. 3 is a schematic structural view of an electrode assembly disclosed in an embodiment of the present application.

Fig. 4 is a schematic structural view of an optical fiber structure disclosed in an embodiment of the present application.

Fig. 5 is a schematic explosion diagram of a battery cell disclosed in an embodiment of the present application.

Fig. 6 is a schematic structural view of another battery cell disclosed in an embodiment of the present application.

Fig. 7 is a schematic structural view of another electrode assembly disclosed in an embodiment of the present application.

Fig. 8 is a schematic diagram of a manufacturing process of a battery cell disclosed in an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

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 in the description of the application in the present application 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. The terms "first," "second," and the like in the description and claims of this application or in the above-described drawings are used for distinguishing between different elements and not for describing a particular sequential or chronological order.

The following description is given with the directional terms as they are used in the drawings and not intended to limit the specific structure of the present application. In the description of the present application, it is also to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be directly connected or indirectly connected through an intermediate. The specific meaning of the above terms in the present application can be understood as appropriate by one of ordinary skill in the art.

Reference in the specification 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 specification. 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 present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "attached" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

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

The "plurality" in the present application means two or more (including two), and similarly, "plural" means two or more (including two) and "plural" means two or more (including two).

Reference to a battery in the embodiments of the present application refers to a single physical module that includes one or more battery cells to provide higher voltage and capacity. For example, the battery referred to in the present application may include a battery module or a battery pack, etc. Batteries generally include a case for enclosing one or more battery cells. The box can avoid liquid or other foreign matters to influence the charging or discharging of battery monomer.

The battery cell may include a lithium ion secondary battery, a lithium ion primary battery, a lithium sulfur battery, a sodium lithium ion battery, a sodium ion battery, a magnesium ion battery, or the like, which is not limited in this embodiment. 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 cylindrical battery cell and the square battery cell are not limited in the embodiment of the application.

The battery monomer comprises an electrode assembly and electrolyte, wherein the electrode assembly comprises a positive plate, a negative plate and an isolating membrane. The battery cell mainly depends on metal ions moving between the positive plate and the negative plate to work. The positive plate comprises a positive current collector and a positive active substance layer, wherein the positive active substance layer is coated on the surface of the positive current collector, the current collector which is not coated with the positive active substance layer protrudes out of the current collector which is coated with the positive active substance layer, and the current collector which is not coated with the positive active substance layer is used as a positive electrode lug. Taking a lithium ion battery as an example, the material of the positive electrode current collector may be aluminum, and the positive electrode active material may be lithium cobaltate, lithium iron phosphate, ternary lithium, lithium manganate, or the like. The negative pole piece includes negative current collector and negative pole active substance layer, and the negative pole active substance layer coats in the surface of negative current collector, and the mass flow body protrusion in the mass flow body of coating the negative pole active substance layer of uncoated negative pole active substance layer, the mass flow body of uncoated negative pole active substance layer is as negative pole utmost point ear. The material of the negative electrode current collector may be copper, and the negative electrode active material may be carbon, silicon, or the like. In order to ensure that the fuse is not fused when a large current is passed, the number of the positive electrode tabs is multiple and the positive electrode tabs are stacked together, and the number of the negative electrode tabs is multiple and the negative electrode tabs are stacked together. The material of the isolation film can be PP or PE, etc. 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.

With the development of battery technology and the arrival of the electric era, people put forward higher and higher demands on the safety, reliability and intelligent degree of a battery system, and the demands are on monitoring various physical quantity changes, such as temperature, vibration, air pressure, stress and the like, in the using process of a battery in real time in more dimensions. However, the battery has a fine internal structure, a complex physical and chemical environment and a complex assembly process, and these factors need to be comprehensively considered to monitor the battery parameters.

In view of this, the present application provides an electrode assembly, in which a sampling structure is interposed between a positive electrode plate and a separator, and/or between a negative electrode plate and a separator, so as to enable the sampling structure to monitor internal information of a battery.

The technical scheme described in the embodiment of the application is applicable to various devices using batteries, such as mobile phones, portable devices, notebook computers, battery cars, electric toys, electric tools, electric vehicles, ships, spacecrafts and the like, and the spacecrafts comprise airplanes, rockets, space shuttles, spacecrafts and the like.

It should be understood that the technical solutions described in the embodiments of the present application are not limited to be applied to the above-described devices, but may also be applied to all devices using batteries, and for brevity of description, the following embodiments are all described by taking an electric vehicle as an example.

For example, as shown in fig. 1, which is a schematic structural diagram of a vehicle 40 according to an embodiment of the present disclosure, the vehicle 40 may be a fuel-oil vehicle, a gas-fired vehicle, or a new energy vehicle, and the new energy vehicle may be a pure electric vehicle, a hybrid electric vehicle, or an extended range vehicle. The vehicle 40 may be provided with a motor 80, a controller 60, and a battery 100 inside, the controller 60 being configured to control the battery 100 to supply power to the motor 80. For example, the battery 100 may be provided at the bottom or the head or tail of the vehicle 40. The battery 100 may be used for powering the vehicle 40, for example, the battery 100 may be used as an operating power source for the vehicle 40 for circuitry of the vehicle 40, for example, for power requirements for operation during start-up, navigation, and operation of the vehicle 40. In another embodiment of the present application, the battery 100 may be used not only as an operating power source of the vehicle 40, but also as a driving power source of the vehicle 40, instead of or in part replacing fuel or natural gas to provide driving power for the vehicle 40.

In order to meet different power requirements, the battery may include a plurality of battery cells, wherein the plurality of battery cells may be connected in series or in parallel or in series-parallel, and the series-parallel refers to a mixture of series connection and parallel connection. The battery may also be referred to as a battery pack. Alternatively, a plurality of battery cells may be connected in series or in parallel or in series-parallel to form a battery module, and a plurality of battery modules may be connected in series or in parallel or in series-parallel to form a battery. That is, a plurality of battery cells may directly constitute a battery, or a battery module may be first constituted and then a battery may be constituted.

Fig. 2 shows a schematic structural diagram of a battery 100 according to an embodiment of the present application, and the battery 100 may include a plurality of battery cells 20. The battery 100 may further include a case (or cover), the case is hollow, and the plurality of battery cells 20 are accommodated in the case. As shown in fig. 2, the case may comprise two parts, herein referred to as a first part 111 and a second part 112, respectively, the first part 111 and the second part 112 snap together. The shape of the first and

second portions

111 and 112 may be determined according to the shape of a combination of a plurality of battery cells 20, and the first and

second portions

111 and 112 may each have one opening. For example, each of the first portion 111 and the second portion 112 may be a hollow rectangular parallelepiped and only one surface of each may be an opening surface, the opening of the first portion 111 and the opening of the second portion 112 are oppositely disposed, and the first portion 111 and the second portion 112 are fastened to each other to form a box body having a closed chamber. The plurality of battery cells 20 are connected in parallel or in series-parallel combination and then placed in a box formed by buckling the first part 111 and the second part 112.

Optionally, the battery 100 may also include other structures, which are not described in detail herein. For example, the battery 100 may further include a bus member for electrically connecting the plurality of battery cells 20, such as in parallel or in series-parallel. Specifically, the bus member may achieve electrical connection between the battery cells 20 by connecting electrode terminals of the battery cells 20. Further, the bus bar member may be fixed to the electrode terminals of the battery cells 20 by welding. The electric energy of the plurality of battery cells 20 can be further led out through the box body by the conductive mechanism. Alternatively, the conductive means may also belong to the bus bar member.

The number of the battery cells 20 may be set to any number according to different power requirements. A plurality of battery cells 20 may be connected in series, parallel, or series-parallel to achieve greater capacity or power. Since the number of the battery cells 20 included in each battery 100 may be large, the battery cells 20 may be arranged in groups for convenience of installation, each group of the battery cells 20 constituting a battery module. The number of the battery cells 20 included in the battery module is not limited and may be set as required.

Fig. 3 shows a schematic structural view of the electrode assembly 22 according to the embodiment of the present application. As shown in fig. 3, the electrode assembly 22 includes: the electrode comprises a positive electrode plate 2201, a negative electrode plate 2202 and an isolating film 2203, wherein the isolating film 2203 is arranged between the positive electrode plate 2201 and the negative electrode plate 2202.

The positive pole piece 2201 comprises a positive pole current collector and a positive pole active material layer, the positive pole active material layer is coated on the surface of the positive pole current collector, the negative pole piece 2202 comprises a negative pole current collector and a negative pole active material layer, the negative pole active material layer is coated on the surface of the negative pole current collector, the isolating film 2203 is positioned between the positive pole piece 2201 and the negative pole piece 2202, and the isolating film is mainly used for separating the positive pole active material from the negative pole active material so as to reduce the risk of short circuit between the positive pole piece 2201 and the negative pole piece 2202.

Optionally, as shown in fig. 3, the electrode assembly 22 further includes a sampling structure 2204, wherein the sampling structure 2204 is sandwiched between the positive electrode plate 2201 and the isolation film 2203, and/or between the negative electrode plate 2202 and the isolation film 2203, so as to obtain the internal information of the battery.

In the present embodiment, the term "sandwiching" has a meaning of not only contacting but also receiving a force. Specifically, the sampling structure 2204 is sandwiched between the positive electrode plate 2201 and the isolation film 2203, which means that the sampling structure 2204 is in contact with the positive electrode plate 2201 and the isolation film 2203, respectively, and the sampling structure 2204 is also fixedly disposed between the positive electrode plate 2201 and the isolation film 2203 due to the compression of the positive electrode plate 2201 and the isolation film 2203. Similarly, the sampling structure 2204 is sandwiched between the negative electrode plate 2202 and the isolation film 2203, which means that the sampling structure 2204 is in contact with the negative electrode plate 2202 and the isolation film 2203, respectively, and the sampling structure 2204 is also fixedly arranged between the negative electrode plate 2202 and the isolation film 2203 due to being pressed by the negative electrode plate 2202 and the isolation film 2203.

Therefore, the electrode assembly 22 provided in the embodiment of the present application can monitor the internal information of the battery by the sampling structure 2204 by interposing the sampling structure 2204 between the positive electrode plate 2201 and the isolation film 2203, and/or between the negative electrode plate 2202 and the isolation film 2203.

In addition, according to the electrode assembly 22 provided in the embodiment of the present application, since the sampling structure 2204 is disposed between the positive electrode plate 2201 and the isolation film 2203, and/or between the negative electrode plate 2202 and the isolation film 2203, the structures of the electrode plate and the isolation film do not need to be changed, and therefore, the manufacturing processes of the existing electrode plate and the isolation film can be compatible.

Alternatively, in the present embodiment, the electrode assembly 22 has a laminate structure in which a plurality of layers are arranged. In other words, the electrode assembly 22 may include a plurality of layers of the positive electrode tab 2201, the negative electrode tab 2202, and the separator 2203 in the thickness direction.

In this embodiment, since the sampling structure 2204 is disposed between the positive electrode tab 2201 and the separator 2203, and/or between the negative electrode tab 2202 and the separator 2203, it is possible to achieve comprehensive monitoring of internal information of the battery having the electrode assembly 22 of the multi-layered laminate structure.

Optionally, in embodiments of the present application, the sampling structure 2204 at least partially covers a non-edge region of the electrode assembly 22.

It should be explained that the non-edge region of the electrode assembly 22 refers to the non-edge region of the electrode assembly 22 in the thickness direction. That is, the non-edge region of the electrode assembly 22 refers to a region of the electrode assembly 22 that is closer to the center of the electrode assembly 22 away from the surface of the electrode assembly 22 in the thickness direction thereof. For example, the electrode assembly is overlapped in the thickness direction in the order of a first positive electrode sheet, a first separator, a first negative electrode sheet, a second separator, a second positive electrode sheet, a third separator, and a second negative electrode sheet. I.e., the electrode assembly 22 includes 7 layers in the thickness direction, the non-edge region may refer to the middle 5 layers. That is, the sampling structure 2204 may be disposed in the electrode assembly between the first to third separators.

In this embodiment, fixing the sampling structure is facilitated by locating the sampling structure in a non-edge region of the electrode assembly.

Alternatively, the electrode assembly 22 in the embodiment of the present application may be a wound structure or a laminated structure.

For electrode assembly 22 wound in a multi-turn wound configuration, sampling structure 2204 may be disposed between a pole piece and a separator film in an electrode assembly of at least one turn of the wound configuration, e.g., between positive pole piece 2201 and separator film 2203, and/or between negative pole piece 2202 and separator film 2203, the at least one turn excluding the innermost and outermost turns of the plurality of turns.

In this embodiment, for an electrode assembly of a wound structure, by disposing the sampling structure 2204 in the electrode assembly of at least one turn except for the innermost turn and the outermost turn, it is advantageous to fix the sampling structure 2204 by an interlayer binding force.

For the electrode assembly 22 of the stacked multi-layer lamination structure, the electrode assembly 22 may be formed of a plurality of positive electrode plates 2201, a plurality of separators 2203, and a plurality of negative electrode plates 2202 in such a manner that one positive electrode plate 2201, one separator 2203, and one negative electrode plate 2202 are sequentially overlapped, and then the sampling structure 2204 may be disposed between any one of the electrode plates and the separator 2203.

Further, the sampling structure 2204 may be disposed in an electrode assembly that is not the outermost layer. For example, the sampling structure 2204 may be disposed between the non-outermost positive pole piece 2201 and the separator 2203, and/or the sampling structure 2204 may be disposed between the non-outermost negative pole piece 2202 and the separator 2203. The non-outermost positive electrode tab 2201 may refer to the positive electrode tab 2201 other than the positive electrode tab 2201 closest to the surface of the electrode assembly 22 in the thickness direction of the electrode assembly 22. Likewise, the negative electrode tab 2202 that is not the outermost layer may also refer to the negative electrode tab 2202 other than the negative electrode tab 2202 closest to the surface of the electrode assembly 22 in the thickness direction of the electrode assembly 22.

In this embodiment, for electrode assembly 22 of a lamination stack, by disposing sampling structure 2204 in the non-outermost electrode assembly, it is advantageous to secure sampling structure 2204 by an interlaminar binding force.

Optionally, as shown in fig. 4, in the embodiment of the present application, the sampling structure 2204 is an optical fiber structure, and the optical fiber structure includes an optical fiber 2204a and a plurality of optical fiber sensors 2204b engraved on the optical fiber 2204 a.

The optical fiber sensor 2204b has the characteristics of small size, flexibility, electromagnetic insensitivity, high sensitivity, corrosion resistance, rich functions and the like, so that the monitoring of the internal information of the battery by using the optical fiber sensor 2204b becomes a very reliable mode. Second, the optical fiber sensor 2204b is an optical sensor based on the optical sensing principle, and is used for monitoring the internal information of the battery during use. The optical fiber 2204a is used for transmitting the detection light to the optical fiber sensor 2204b in the electrode assembly 22 and outputting the information monitored by the optical fiber sensor 2204b to the demodulation unit outside the battery in the form of signal light. That is, the optical fiber 2204a extending to the outside of the battery may be connected with a demodulation unit, which may be used to provide the detection light required by the optical fiber sensor 2204b, and to receive the signal light returned by the optical fiber sensor 2204b and analyze it.

In addition, in the present embodiment, by etching a plurality of optical fiber sensors 2204b on one optical fiber 2204a, various information of different portions inside the battery can be monitored.

It should be noted that the sampling structure 2204 of the embodiment of the present application may be other types of sensors besides the optical fiber structure. For example, an ultrasonic sensor, a photoelectric sensor, and the like, which are not limited in the embodiments of the present application.

Optionally, one or more optical fibers 2204a may be implanted between any of the pole pieces of electrode assembly 22 and separator 2203. In addition, the embodiment of the present invention is not limited to implanting the optical fiber 2204a in one interlayer, and the optical fiber 2204a may be implanted in a plurality of interlayers.

Optionally, in this embodiment, the plurality of optical fiber sensors 2204b includes at least one of a single-mode bragg grating sensor, a multi-mode bragg grating sensor, a tilted bragg grating sensor, and a micro-structured grating sensor.

It should be understood that the structure of the optical fiber sensor 2204b is not limited in the embodiments of the present application, for example, the optical fiber sensor 2204b may also be other optical fiber sensors without changing the macro structure of the optical fiber.

The Bragg grating sensor is an optical fiber sensor with the highest use frequency and the widest application range, so that the electrode assembly of the embodiment of the application has universality by monitoring the internal information of the battery by the Bragg grating sensor.

Optionally, in the embodiment of the present application, the length of the optical fiber sensor 2204b ranges from 0.1cm to 10 cm.

In this embodiment, the length of the optical fiber sensor 2204b is set to 0.1-10cm, which not only can prevent the optical signal from being lost, but also can realize the monitoring on a micro size.

Optionally, in the embodiment of the present application, the length of the optical fiber sensor 2204b is 1 cm.

In this embodiment, setting the length of the fiber optic sensor 2204b to 1cm can meet the size and space monitoring requirements of most electrode assemblies.

Optionally, in the present embodiment, the diameter of the optical fiber 2204a ranges from 25um to 250 um.

In this embodiment, the diameter of the optical fiber 2204a is set between 25-250um, which not only can ensure that the optical signal transmission is not lost, but also can meet the size and space monitoring requirements of most electrode assemblies.

Optionally, in the present embodiment, the diameter of the optical fiber 2204a is 120 um.

In this embodiment, setting the diameter of the optical fiber 2204a to 120um, which is closer to the interlayer gap of the electrode assembly, allows the coupling of the optical fiber with the electrode assembly without increasing the thickness of the electrode assembly.

Optionally, in the embodiment of the present application, the internal information of the battery includes at least one of temperature, pressure, strain, anion and cation concentration, turbidity of the electrolyte, composition of gas, aging degree of the electrolyte, gas content, swelling force, interface state, and reaction rate.

That is, the sampling structure 2204 of the embodiment of the present application can monitor the above-mentioned various information of the battery, which is beneficial to improving the performance of the battery.

Alternatively, the electrode assembly 22 of the embodiment of the present application may be cylindrical or square.

Fig. 5 shows a schematic explosion diagram of the battery cell 20 provided in the embodiment of the present application. As shown in fig. 5, the battery cell 20 may include at least one electrode assembly 22 and a case 21 as described in the above embodiments, the case 21 accommodating the electrode assembly 22.

In this embodiment, the electrode assembly 22 having the sampling structure 2204 is disposed in the battery cell 20, so that the sampling structure 2204 can monitor the internal information of the battery cell 20.

Alternatively, in the present embodiment, the sampling structure 2204 is an optical fiber structure, and the housing 21 of the battery cell 20 is provided with a through hole 24 to guide the optical fiber 2204a in the optical fiber structure inside the electrode assembly 22 to the outside of the housing 21.

In this embodiment, the through hole 24 is formed in the housing 21 of the battery cell 20, so that the internal information of the battery monitored by the optical fiber sensor 2204b can be transmitted to the demodulation unit outside the battery cell 20 through the optical fiber 2204a, and the internal information of the battery cell 20 can be analyzed.

As shown in fig. 5, the housing 21 may include a case 211 and a cover 212. The case 211 is determined according to the shape of one or more electrode assemblies 22 after being combined, for example, the case 211 may be a hollow rectangular parallelepiped or a square or a cylinder, and one of the faces of the case 211 has an opening so that one or more electrode assemblies 22 can be placed in the case 211. For example, when the housing 211 is a hollow rectangular parallelepiped or square, one of the planes of the housing 211 is an open plane, i.e., the plane has no wall body so that the housing 211 communicates inside and outside. When the housing 211 may be a hollow cylinder, the end surface of the housing 211 is an open surface, i.e., the end surface has no wall body so that the housing 211 is communicated with the inside and the outside. The cap plate 212 covers the opening and is connected with the case 211 to form a closed cavity in which the electrode assembly 22 is placed. The case 211 is filled with an electrolyte, such as an electrolytic solution.

Alternatively, as shown in fig. 5, a through hole 24 may be provided on the cover plate 212 so as to guide the optical fiber 2204a to the outside of the cover plate 212.

In this embodiment, the through hole 24 for guiding the optical fiber 2204a is disposed on the cover plate 212, so that the optical fiber 2204a can pass through the cover plate 212 to the outside of the battery cell 20, which is beneficial to the process packaging of the battery cell 20.

It should be noted that the optical fiber 2204a extending to the outside of the cover plate 212 may have any length. For example, it may be 50 cm.

Alternatively, in the present embodiment, the electrode assembly 22 is provided with tabs, and the cap plate 212 is provided with electrode terminals, with the tabs and the electrode terminals being electrically connected.

Alternatively, the electrode assembly 22 may have tabs arranged in a single-sided tab arrangement manner or a double-sided tab arrangement manner.

In this embodiment, the cap plate 212 is provided with electrode terminals and through-holes 24 for guiding the optical fibers 2204a such that the optical fibers 2204a may extend in the same direction as the tabs, thereby facilitating the process packaging of the battery cell 20.

Alternatively, as shown in fig. 5, the battery cell 20 may further include two electrode terminals 214, and the two electrode terminals 214 may be disposed on the cap plate 212. The cap plate 212 is generally in the shape of a flat plate, and two electrode terminals 214 are fixed to the flat plate surface of the cap plate 212, the two electrode terminals 214 being a positive electrode terminal 214a and a negative electrode terminal 214b, respectively. Each electrode assembly 22 has a first tab 221a and a second tab 222 a. The first tab 221a and the second tab 222a have opposite polarities. For example, when the first tab 221a is a positive electrode tab, the second tab 222a is a negative electrode tab. For another example, when the first tab 221a is a negative electrode tab, the second tab 222a is a positive electrode tab. The first tab 221a of one or more electrode assemblies 22 is connected with one electrode terminal by one connecting member 23, and the second tab 222a of one or more electrode assemblies 22 is connected with the other electrode terminal by the other connecting member 23. For example, the positive electrode terminal 214a is connected to a positive electrode tab through one connecting member 23, and the negative electrode terminal 214b is connected to a negative electrode tab through the other connecting member 23.

Further, the through hole 24 is closer to the negative electrode terminal 214b than to the positive electrode terminal 214 a.

In general, the lid plate 212 of the battery cell 20 is provided with not only the electrode terminal 214 but also the pour hole 25, and the pour hole 25 is generally located closer to the positive electrode terminal 214a, so that the through hole 24 for guiding the optical fiber 2204a may be located closer to the negative electrode terminal 214a in order to avoid the pour hole 25.

As an example, a pressure relief mechanism 213 may also be provided on one wall of the battery cell 20. As shown in fig. 5, the pressure relief mechanism 213 is provided on the cover plate 212. The pressure relief mechanism 213 is configured to actuate to relieve the internal pressure or temperature of the battery cell 20 when the internal pressure or temperature reaches a threshold value.

The pressure relief mechanism 213 may be a part of the cover plate 212, or may be a separate structure from the cover plate 212 and fixed to the cover plate 212 by welding, for example. When the pressure relief mechanism 213 is a part of the cover 212, for example, the pressure relief mechanism 213 may be formed by providing a notch on the cover 212, and the thickness of the cover 212 corresponding to the notch is smaller than the thickness of the other regions of the pressure relief mechanism 213 except the notch. The score is the weakest point of the pressure relief mechanism 213. When too much gas generated by the single battery cell 20 raises the internal pressure of the case 211 to reach a threshold value or the internal temperature of the single battery cell 20 rises to reach the threshold value due to heat generated by the internal reaction of the single battery cell 20, the pressure relief mechanism 213 may rupture at the notch to cause the inside and the outside of the case 211 to communicate with each other, and the gas pressure and the temperature are released outwards by the rupture of the pressure relief mechanism 213, thereby preventing the single battery cell 20 from exploding.

Alternatively, when the pressure relief mechanism 213 is provided on the lid plate 212 of the battery cell 20, the through hole 24 for guiding the optical fiber 2204a should be free from the pressure relief mechanism 213.

Optionally, in the embodiment of the present application, the angle between the optical fiber 2204a and the vertical direction of the cover plate 212 when extending to the through hole 24 ranges from 0 ° to 90 °.

In this embodiment, the angle between the optical fiber 2204a and the vertical direction of the cover plate 212 when the optical fiber 2204a extends to the through hole 24 is set to 0 ° to 90 °, so that damage to the optical fiber 2204a due to an excessively large angle can be avoided.

Alternatively, in the present embodiment, the angle between the optical fiber 2204a and the vertical direction when extending to the through hole 24 is 30 °.

In this embodiment, the angle of the optical fiber 2204a extending to the through hole 24 with respect to the vertical direction of the cover plate 212 is set to 30 °, and damage to the optical fiber 2204a due to an excessive angle can be avoided.

Optionally, in the present embodiment, the size of the through hole 24 ranges between 1mm and 5 mm.

In the embodiment, the size of the through hole 24 is set to be 1-5 mm, so that drilling and packaging are facilitated.

Optionally, in the present embodiment, the size of the through hole 24 is 2 mm.

In this embodiment, the size of the through hole 24 is set to 2mm, which facilitates drilling and packaging.

Alternatively, in the present embodiment, the through hole 24 and the optical fiber 2204a led out from the through hole 24 are sealed by glue.

In this embodiment, the through hole 24 and the optical fiber 2204a led out from the through hole 24 are sealed with glue, which can improve the sealing performance of the battery cell 20, thereby improving the safety of the battery cell 20.

Optionally, in the embodiment of the present application, the glue is an epoxy resin, a polyacrylic acid, an ultraviolet curing glue, or a modified epoxy resin.

In this embodiment, the through-hole 24 is sealed with an ultraviolet curing paste, which is corrosion resistant, swelling resistant, and has good compatibility with an electrolyte.

The following describes in detail the manufacturing process of the battery cell 30 according to the embodiment of the present application with reference to fig. 6 and 7. It should be noted that, although the reference numerals used for the battery cell 30 shown in fig. 6 and the components inside the battery cell 30 are different from those used for the battery cell 20 shown in fig. 5, the structures and functions of the same components are identical, that is, the descriptions of the components in fig. 6 may refer to fig. 5, and are not repeated herein for brevity. As shown in fig. 6, the battery cell 30 includes an electrode assembly 10, a case 11, a cover plate 9, an optical fiber structure 1 with a temperature sensing grating, and an encapsulation glue 6. The optical fiber structure 1 with the temperature sensing grating is disposed between the pole pieces and the separator of the electrode assembly 10, and is fixed by tension between the layers during winding. As shown in fig. 7, the temperature sensing grating 16 is disposed at a position to be monitored inside the electrode assembly to be wound, and the transmission fiber 15 is connected to the temperature sensing grating 16 and extends from the temperature sensing grating 16 to the position outside the electrode sheet.

Specifically, the manufacturing flow may include the following steps.

S110, the optical fiber structure 1 with the temperature sensing grating 16 is placed between any of the pole pieces and the separator, and the transmission optical fiber 15 is extended from the side where the tab is disposed by an appropriate length and wound together with the electrode assembly 10.

Alternatively, the optical fiber structure 1 may be disposed between the negative electrode tab 14 and the separator 13 or between the positive electrode tab 12 and the separator 13, and preferably, the optical fiber structure 1 is disposed between the positive electrode tab 12 and the separator 13.

Optionally, the diameter of the transmission fiber 15 in the fiber structure 1 is 25-250um, preferably the diameter of the transmission fiber 15 is 120 um.

Optionally, one or more temperature sensing gratings 16 may be engraved on each transmission fiber 15.

Optionally, the temperature sensing grating 16 is a fiber bragg grating.

Optionally, the length of the temperature sensing grating 16 is 0.1-10cm, and preferably, the length of the temperature sensing grating 16 is 1 cm.

Alternatively, the length of the transmission fiber 15 extending out of the electrode assembly 10 may be any length, for example, 50 cm.

Alternatively, the optical fiber structure 1 may be implanted between one or more layers. And the implanted layer of the optical fiber structure 1 may be located at any layer of the electrode assembly 10.

And S120, performing hot-press shaping after the electrode assembly 10 implanted in the optical fiber structure 1 is wound.

Alternatively, the hot pressing process parameters are the same as those of the general multi-layer electrode assembly 10.

S130, the electrode assembly 10 implanted with the optical fiber structure 1 is placed in the case 11, and the transmission optical fiber 15 having a tab side beyond the electrode assembly 10 is wound to a negative tab side.

Alternatively, the positive electrode tab 7 of the electrode assembly 10 is located on the same side as the positive electrode post 3, and the negative electrode tab 8 is located on the same side as the negative electrode post 2.

Optionally, the transmission fiber 15 is wound to the extreme ear side at an angle of 0 ° to 90 °, preferably 30 °, to the normal.

S140, the cover plate 9 with the reserved through hole is placed above the shell 11, the transmission optical fiber 15 is led out from the through hole, and the cover plate 9 and the shell 11 are packaged through laser welding.

Alternatively, the through hole should avoid other cover members such as the explosion-proof valve 4 and the pour hole 5 as much as possible.

Optionally, the size of the through hole is 1mm to 5mm, preferably 2 mm.

S150, sealing the through hole on the cover plate 9 and the led-out optical fiber by using polymer glue 6.

Optionally, the polymer glue 6 is an epoxy, polyacrylic or uv curable glue, preferably a uv curable glue.

It should be noted that, although the embodiments of the present application mostly use an electrode assembly in a winding structure as an example for describing the technical solution, those skilled in the art understand that the electrode assembly described herein may be applied to an electrode assembly in a lamination structure, and the battery cell described herein may be applied to a battery cell including an electrode assembly in a winding structure, and for brevity, the present application is not repeated.

The embodiment of the application also provides a battery, and the battery can comprise the battery monomer of the various embodiments.

An embodiment of the present application further provides a powered device, which may include the battery in the foregoing embodiments, where the battery is used to provide power for the powered device.

Alternatively, the powered device may be a vehicle 40, a watercraft or a spacecraft.

While the application has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the application. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein but is to cover all embodiments that may fall within the scope of the appended claims.

Claims

1. An electrode assembly for a battery, comprising: the separator is arranged between the positive pole piece and the negative pole piece;

the electrode assembly further includes a sampling structure interposed between the positive electrode tab and the separator, and/or between the negative electrode tab and the separator, so as to acquire internal information of the battery.

2. The electrode assembly of claim 1, wherein the electrode assembly is in a stacked structure of a plurality of layers.

3. The electrode assembly of claim 1, wherein the sampling structure at least partially covers a non-edge region of the electrode assembly.

4. The electrode assembly of claim 2, wherein the laminated structure is a wound structure wound a plurality of turns, the sampling structure being provided in the electrode assembly of at least one of the turns, the at least one turn excluding an innermost turn and an outermost turn of the plurality of turns.

5. The electrode assembly of claim 2, wherein the laminate structure is a lamination stack of stacked layers, the sampling structure being disposed in the electrode assembly that is not an outermost layer.

6. The electrode assembly of claim 1, wherein the sampling structure comprises an optical fiber structure comprising an optical fiber and a plurality of optical fiber sensors inscribed on the optical fiber.

7. The electrode assembly of claim 6, wherein the plurality of fiber optic sensors includes at least one of a single mode bragg grating sensor, a multi-mode bragg grating sensor, a tilted bragg grating sensor, and a micro-structured grating sensor.

8. The electrode assembly of claim 6, wherein the fiber optic sensor has a length ranging between 0.1cm and 10 cm.

9. The electrode assembly of claim 8, wherein the fiber optic sensor has a length of 1 cm.

10. The electrode assembly of claim 6, wherein the optical fiber has a diameter ranging between 25um and 250 um.

11. The electrode assembly of claim 10, wherein the optical fiber has a diameter of 120 um.

12. The electrode assembly according to any one of claims 1 to 11, wherein the internal information of the battery includes at least one of temperature, pressure, strain, cation and anion concentration, turbidity of the electrolyte, composition of gas, aging degree of the electrolyte, gas content, swelling force, interface state, and reaction rate.

13. A battery cell comprising a case for housing the electrode assembly as recited in any one of claims 1 to 12, and the electrode assembly.

14. The battery cell as recited in claim 13 wherein the sampling structure is an optical fiber structure and the housing is provided with a through hole for the optical fiber in the optical fiber structure to pass through the housing.

15. The battery cell as recited in claim 14 wherein the housing comprises a housing and a cover plate, the through-hole being provided in the cover plate.

16. The battery cell as recited in claim 15, wherein the electrode assembly is provided with a tab, and the cap plate is provided with an electrode terminal, the tab being electrically connected with the electrode terminal.

17. The battery cell as recited in claim 16, wherein the electrode assembly is provided with a positive electrode tab and a negative electrode tab at a side facing the cap plate, the cap plate is provided with a positive electrode terminal and a negative electrode terminal, the positive electrode tab is electrically connected with the positive electrode terminal, and the negative electrode tab is electrically connected with the negative electrode terminal;

the through hole is closer to the negative electrode terminal than to the positive electrode terminal.

18. The battery cell as recited in claim 15 wherein the optical fiber extends through the through hole at an angle in a range of 0 ° to 90 ° from the perpendicular to the cover plate.

19. The battery cell as recited in claim 18 wherein the optical fiber extends to the through hole at an angle of 30 ° from the vertical.

20. The battery cell according to any of claims 14-19, wherein the size of the through hole ranges between 1mm and 5 mm.

21. The battery cell as recited in claim 20 wherein the through-hole has a size of 2 mm.

22. The battery cell according to any one of claims 14 to 19, wherein the through hole and the optical fiber led out from the through hole are sealed by glue.

23. The battery cell of claim 22, wherein the glue is an epoxy, a polyacrylic acid, an ultraviolet-cured glue, or a modified epoxy.

24. A battery comprising a cell according to any one of claims 13 to 23.

25. An electrical consumer comprising the battery of claim 24, wherein the battery is configured to provide electrical power to the electrical consumer.