ABSTRACT
Abstract
Provided is a secondary battery where a positive electrode includes a first covered part covered with a positive electrode active material layer and a positive electrode active material non-covered part on a positive electrode foil, and a negative electrode includes a second covered part covered with a negative electrode active material layer and a negative electrode active material non-covered part on a negative electrode foil, one or both of the positive electrode active material non-covered part and the negative electrode active material non-covered part have a surface formed by bending toward the central axis of the wound structure and overlapping each other, and the surface is joined to the positive electrode current-collecting plate or the negative electrode current-collecting plate.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of PCT patent application no. PCT/JP2020/027429, filed on Jul. 15, 2020, which claims priority to Japanese patent application no. JP2019-139814 filed on Jul. 30, 2019, the entire contents of which are being incorporated herein by reference.
BACKGROUND
The present disclosure generally relates to a secondary battery, a battery pack, an electronic device, an electric tool, an electric aircraft, and an electric vehicle.
Lithium ion batteries have been developed for applications that require high power, such as electric tools and automobiles. Methods for achieving high power include a method of high-rate discharge for the flow of a relatively large current from a battery. The high-rate discharge has a problem with the internal resistance of the battery, because of the flow of the large current.
SUMMARY
The present disclosure generally relates to a secondary battery, a battery pack, an electronic device, an electric tool, an electric aircraft, and an electric vehicle.
The conventional battery technology, for example, has a structure with the connection ensured by laser welding between the current-collecting plate and the electrode end, but unwelding, perforating, or sputtering is caused depending on the relationship between the thickness of the current-collecting plate used and the lamination thickness of the core body exposed part. Because nothing is mentioned about the relationship between the both, there has been a problem that welding is not possible in some cases.
Accordingly, an object of the present disclosure is to provide a battery that has a relationship capable of reducing the internal resistance of the battery between the lamination thickness of an active material non-covered part and the thickness of a current-collecting plate.
For solving the above-described problems, the present disclosure provides a secondary battery according to an embodiment including: an electrode wound body that has a positive electrode and a negative electrode stacked with a separator interposed therebetween and has a wound structure; and a positive electrode current-collecting plate and a negative electrode current-collecting plate, accommodated in an exterior can,
where the positive electrode includes a first covered part covered with a positive electrode active material layer and a positive electrode active material non-covered part on a positive electrode foil, and the negative electrode includes a second covered part covered with a negative electrode active material layer and a negative electrode active material non-covered part on a negative electrode foil, one or both of the positive electrode active material non-covered part and the negative electrode active material non-covered part have a surface formed by bending toward the central axis of the wound structure and overlapping each other, the surface is joined to the positive electrode current-collecting plate or the negative electrode current-collecting plate, and the positive electrode and the negative electrode meet 0.2â¤Zâ¤2.0, with Z=tÃm/T where the thickness of the positive electrode foil or negative electrode foil at the joined site farthest from the central axis, of the joined site on the positive electrode side or the joined site on the negative electrode side, is denoted by t (mm), the number of foils overlapped is denoted by m, and the thickness of the positive current-collecting plate or negative current-collecting plate is denoted by T (mm).
Further, the present disclosure provides a battery pack including:
the secondary battery described above; a controller configured to control the secondary battery; and an exterior body that encloses the secondary battery.
The present disclosure provides an electronic device including the secondary battery described above or the battery pack described above.
The present disclosure provides an electric tool according to an embodiment including the battery pack as described herein. The electric tool is configured to use the battery pack as a power supply.
The present disclosure provides an electric aircraft according to an embodiment including:
the battery pack as described herein; a plurality of rotor blades; a motor that rotates each of the rotor blades; a support shaft that supports each of the rotor blades and the motor; a motor controller configured to control rotation of the motor; and a power supply line that supplies power to the motor, where the battery pack is connected to the power supply line.
The present disclosure provides an electric vehicle according to an embodiment including the secondary battery described above, and
including a conversion device that receives power supply from the secondary battery to convert the power to a driving force for the vehicle, and a controller configured to perform information processing related to vehicle control, based on information on the second battery.
According to at least an embodiment of the present disclosure, the foil and the current-collecting plate can be reliably welded, the internal resistance of the battery can be reduced, or a high-power battery can be achieved.
It is to be noted that the contents of the present disclosure are not to be construed as being limited by the effects illustrated in this specification. It should be understood that the effects described in the present specification are only examples, and additional effects may be further provided.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a sectional view of a battery according to an embodiment of the present disclosure.
FIG. 2 is a diagram illustrating an example of a relationship among a positive electrode, a negative electrode, and a separator disposed in an electrode wound body according to an embodiment of the present disclosure.
FIG. 3 A is a plan view of a positive electrode current-collecting plate according to an embodiment of the present disclosure, and FIG. 3 B is a plan view of a negative electrode current-collecting plate according to an embodiment of the present disclosure.
FIG. 4 A to 4 F are diagrams illustrating a process for assembling a battery according to an embodiment of the present disclosure.
FIG. 5 is a diagram that relates to laser welding for a battery according to an embodiment of the present disclosure.
FIG. 6 is a diagram illustrating Examples 1 to 4 according to an embodiment of the present disclosure.
FIG. 7 is a diagram illustrating Comparative Examples 5 and 6.
FIG. 8 is a front view of an electrode wound body according to an embodiment of the present disclosure.
FIGS. 9 A to 9 C are sectional views and a plan view illustrating Examples 7 to 12 according to an embodiment of the present disclosure.
FIGS. 10 A to 10 C are sectional views and a plan view illustrating a positive electrode side of Comparative Example 7 and a negative electrode side of Comparative Example 9.
FIGS. 11 A to 11 C are sectional views and a plan view illustrating Comparative Examples 8 and 10.
FIG. 12 is a connection diagram for use in description of a battery pack as an application example according to an embodiment of the present disclosure.
FIG. 13 is a connection diagram for use in description of an electric tool as an application example according to an embodiment of the present disclosure.
FIG. 14 is a connection diagram for use in description of an unmanned aircraft as an application example according to an embodiment of the present disclosure.
FIG. 15 is a connection diagram for use in description of an electric vehicle as an application example according to an embodiment of the present disclosure.
DETAILED DESCRIPTION
As described herein, the present disclosure will be described based on examples with reference to the drawings, but the present disclosure is not to be considered limited to the examples, and various numerical values and materials in the examples are considered by way of example.
In the embodiment of the present disclosure, a cylindrical lithium ion battery will be described as an example of the secondary battery. Obviously, any battery other than the lithium ion battery or a battery that has any shape other than the cylindrical shape may be used.
First, the overall configuration of the lithium ion battery will be described. FIG. 1 is a schematic sectional view of a lithium ion battery 1 . The lithium ion battery 1 is, for example, a cylindrical lithium ion battery 1 that has an electrode wound body 20 is housed inside an exterior can 11 as shown in FIG. 1 .
Specifically, the lithium ion battery 1 includes, for example, a pair of insulating plates
12 and 13 and an electrode wound body 20 inside the cylindrical exterior can 11 . The lithium ion battery 1 may further, however, include, for example, any one of, or two or more of a positive temperature coefficient (PTC) element, a reinforcing member, and the like inside the exterior can 11 .
The exterior can 11 is a member that mainly houses the electrode wound body 20 . The exterior can 11 is, for example, a cylindrical container with one end thereof opened and the other end thereof closed. More specifically, the exterior can 11 has an opened end ( open end 11 N). The exterior can 11 contains, for example, any one of, or two or more of metal materials such as iron, aluminum, and alloys thereof. The surface of the exterior can 11 may be, however, plated with, for example, any one of, or two or more of metal materials such as nickel.
Each of the insulating plates
12 and 13 is, for example, a dish-shaped plate that has a surface perpendicular to the winding axis of the electrode wound body 20 , that is, a surface perpendicular to the Z axis in FIG. 1 . In addition, the insulating plates
12 and 13 are disposed so as to sandwich the electrode wound body 20 therebetween, for example.
The open end 11 N of the exterior can 11 has, for example, a battery cover 14 and a safety valve mechanism 30 are crimped with a gasket 15 . The battery cover 14 serves as a âcover memberâ according to an embodiment of the present disclosure, and the gasket 15 serves as a âsealing memberâ according to an embodiment of the present disclosure. Thus, with the electrode wound body 20 and the like housed inside the exterior can 11 , the exterior can 11 is sealed. Accordingly, the open end 11 N of the exterior can 11 has a crimped structure (crimped structure 11 R) formed by the battery cover 14 and the safety valve mechanism 30 crimped with the gasket 15 . More specifically, a bent part 11 P is a so-called crimp part, and the crimped structure 11 R is a so-called crimp structure.
The battery co
CROSS REFERENCE TO RELATED APPLICATIONS
The present application is a continuation of PCT patent application no. PCT/JP2020/027429, filed on Jul. 15, 2020, which claims priority to Japanese patent application no. JP2019-139814 filed on Jul. 30, 2019, the entire contents of which are being incorporated herein by reference.
BACKGROUND
The present disclosure generally relates to a secondary battery, a battery pack, an electronic device, an electric tool, an electric aircraft, and an electric vehicle.
Lithium ion batteries have been developed for applications that require high power, such as electric tools and automobiles. Methods for achieving high power include a method of high-rate discharge for the flow of a relatively large current from a battery. The high-rate discharge has a problem with the internal resistance of the battery, because of the flow of the large current.
SUMMARY
The present disclosure generally relates to a secondary battery, a battery pack, an electronic device, an electric tool, an electric aircraft, and an electric vehicle.
The conventional battery technology, for example, has a structure with the connection ensured by laser welding between the current-collecting plate and the electrode end, but unwelding, perforating, or sputtering is caused depending on the relationship between the thickness of the current-collecting plate used and the lamination thickness of the core body exposed part. Because nothing is mentioned about the relationship between the both, there has been a problem that welding is not possible in some cases.
Accordingly, an object of the present disclosure is to provide a battery that has a relationship capable of reducing the internal resistance of the battery between the lamination thickness of an active material non-covered part and the thickness of a current-collecting plate.
For solving the above-described problems, the present disclosure provides a secondary battery according to an embodiment including: an electrode wound body that has a positive electrode and a negative electrode stacked with a separator interposed therebetween and has a wound structure; and a positive electrode current-collecting plate and a negative electrode current-collecting plate, accommodated in an exterior can,
where the positive electrode includes a first covered part covered with a positive electrode active material layer and a positive electrode active material non-covered part on a positive electrode foil, and the negative electrode includes a second covered part covered with a negative electrode active material layer and a negative electrode active material non-covered part on a negative electrode foil, one or both of the positive electrode active material non-covered part and the negative electrode active material non-covered part have a surface formed by bending toward the central axis of the wound structure and overlapping each other, the surface is joined to the positive electrode current-collecting plate or the negative electrode current-collecting plate, and the positive electrode and the negative electrode meet 0.2â¤Zâ¤2.0, with Z=tÃm/T where the thickness of the positive electrode foil or negative electrode foil at the joined site farthest from the central axis, of the joined site on the positive electrode side or the joined site on the negative electrode side, is denoted by t (mm), the number of foils overlapped is denoted by m, and the thickness of the positive current-collecting plate or negative current-collecting plate is denoted by T (mm).
Further, the present disclosure provides a battery pack including:
the secondary battery described above; a controller configured to control the secondary battery; and an exterior body that encloses the secondary battery.
The present disclosure provides an electronic device including the secondary battery described above or the battery pack described above.
The present disclosure provides an electric tool according to an embodiment including the battery pack as described herein. The electric tool is configured to use the battery pack as a power supply.
The present disclosure provides an electric aircraft according to an embodiment including:
the battery pack as described herein; a plurality of rotor blades; a motor that rotates each of the rotor blades; a support shaft that supports each of the rotor blades and the motor; a motor controller configured to control rotation of the motor; and a power supply line that supplies power to the motor, where the battery pack is connected to the power supply line.
The present disclosure provides an electric vehicle according to an embodiment including the secondary battery described above, and
including a conversion device that receives power supply from the secondary battery to convert the power to a driving force for the vehicle, and a controller configured to perform information processing related to vehicle control, based on information on the second battery.
According to at least an embodiment of the present disclosure, the foil and the current-collecting plate can be reliably welded, the internal resistance of the battery can be reduced, or a high-power battery can be achieved.
It is to be noted that the contents of the present disclosure are not to be construed as being limited by the effects illustrated in this specification. It should be understood that the effects described in the present specification are only examples, and additional effects may be further provided.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a sectional view of a battery according to an embodiment of the present disclosure.
FIG. 2 is a diagram illustrating an example of a relationship among a positive electrode, a negative electrode, and a separator disposed in an electrode wound body according to an embodiment of the present disclosure.
FIG. 3 A is a plan view of a positive electrode current-collecting plate according to an embodiment of the present disclosure, and FIG. 3 B is a plan view of a negative electrode current-collecting plate according to an embodiment of the present disclosure.
FIG. 4 A to 4 F are diagrams illustrating a process for assembling a battery according to an embodiment of the present disclosure.
FIG. 5 is a diagram that relates to laser welding for a battery according to an embodiment of the present disclosure.
FIG. 6 is a diagram illustrating Examples 1 to 4 according to an embodiment of the present disclosure.
FIG. 7 is a diagram illustrating Comparative Examples 5 and 6.
FIG. 8 is a front view of an electrode wound body according to an embodiment of the present disclosure.
FIGS. 9 A to 9 C are sectional views and a plan view illustrating Examples 7 to 12 according to an embodiment of the present disclosure.
FIGS. 10 A to 10 C are sectional views and a plan view illustrating a positive electrode side of Comparative Example 7 and a negative electrode side of Comparative Example 9.
FIGS. 11 A to 11 C are sectional views and a plan view illustrating Comparative Examples 8 and 10.
FIG. 12 is a connection diagram for use in description of a battery pack as an application example according to an embodiment of the present disclosure.
FIG. 13 is a connection diagram for use in description of an electric tool as an application example according to an embodiment of the present disclosure.
FIG. 14 is a connection diagram for use in description of an unmanned aircraft as an application example according to an embodiment of the present disclosure.
FIG. 15 is a connection diagram for use in description of an electric vehicle as an application example according to an embodiment of the present disclosure.
DETAILED DESCRIPTION
As described herein, the present disclosure will be described based on examples with reference to the drawings, but the present disclosure is not to be considered limited to the examples, and various numerical values and materials in the examples are considered by way of example.
In the embodiment of the present disclosure, a cylindrical lithium ion battery will be described as an example of the secondary battery. Obviously, any battery other than the lithium ion battery or a battery that has any shape other than the cylindrical shape may be used.
First, the overall configuration of the lithium ion battery will be described. FIG. 1 is a schematic sectional view of a lithium ion battery 1 . The lithium ion battery 1 is, for example, a cylindrical lithium ion battery 1 that has an electrode wound body 20 is housed inside an exterior can 11 as shown in FIG. 1 .
Specifically, the lithium ion battery 1 includes, for example, a pair of insulating plates
12 and 13 and an electrode wound body 20 inside the cylindrical exterior can 11 . The lithium ion battery 1 may further, however, include, for example, any one of, or two or more of a positive temperature coefficient (PTC) element, a reinforcing member, and the like inside the exterior can 11 .
The exterior can 11 is a member that mainly houses the electrode wound body 20 . The exterior can 11 is, for example, a cylindrical container with one end thereof opened and the other end thereof closed. More specifically, the exterior can 11 has an opened end ( open end 11 N). The exterior can 11 contains, for example, any one of, or two or more of metal materials such as iron, aluminum, and alloys thereof. The surface of the exterior can 11 may be, however, plated with, for example, any one of, or two or more of metal materials such as nickel.
Each of the insulating plates
12 and 13 is, for example, a dish-shaped plate that has a surface perpendicular to the winding axis of the electrode wound body 20 , that is, a surface perpendicular to the Z axis in FIG. 1 . In addition, the insulating plates
12 and 13 are disposed so as to sandwich the electrode wound body 20 therebetween, for example.
The open end 11 N of the exterior can 11 has, for example, a battery cover 14 and a safety valve mechanism 30 are crimped with a gasket 15 . The battery cover 14 serves as a âcover memberâ according to an embodiment of the present disclosure, and the gasket 15 serves as a âsealing memberâ according to an embodiment of the present disclosure. Thus, with the electrode wound body 20 and the like housed inside the exterior can 11 , the exterior can 11 is sealed. Accordingly, the open end 11 N of the exterior can 11 has a crimped structure (crimped structure 11 R) formed by the battery cover 14 and the safety valve mechanism 30 crimped with the gasket 15 . More specifically, a bent part 11 P is a so-called crimp part, and the crimped structure 11 R is a so-called crimp structure.
The battery cover 14 is a member that closes the open end 11 N of the exterior can 11 mainly with the electrode wound body 20 and the like housed inside the exterior can 11 . The battery cover 14 contains, for example, the same material as the material that forms the exterior can 11 . The central region of the battery cover 14 protrudes in the +Z direction, for example. Thus, the region (peripheral region) of the battery cover 14 other than the central region has contact with, for example, the safety valve mechanism 30 .
The gasket 15 is a member mainly interposed between the exterior can 11 ( bent part 11 P) and the battery cover 14 to seal the gap between the bent part 11 P and the battery cover 14 . For example, asphalt or the like may be, however, applied to the surface of the gasket 15 .
The gasket 15 contains, for example, any one of, or two or more of insulating materials. The types of the insulating materials are not particularly limited, and may be, for example, a polymer material such as a polybutylene terephthalate (PBT) and a polypropylene (PP). In particular, the insulating material is preferably a polybutylene terephthalate. This is because the gap between the bent part 11 P and the battery cover 14 is sufficiently sealed while the exterior can 11 and the battery cover 14 are electrically separated from each other.
The safety valve mechanism 30 mainly releases the sealed state of the exterior can 11 to release the pressure (internal pressure) inside the exterior can 11 , if necessary, when the internal pressure is increased. The cause of the increase in the internal pressure of exterior can 11 is, for example, a gas generated due to a decomposition reaction of an electrolytic solution during charging or discharging.
For the cylindrical lithium ion battery, a band-shaped positive electrode 21 and a band-shaped negative electrode 22 are spirally wound with a separator 23 interposed therebetween, impregnated with an electrolytic solution, and housed in the exterior can 11 . The positive electrode 21 is obtained by forming a positive electrode active material layer 21 B on one or both surfaces of a positive electrode foil 21 A, and the material of the positive electrode foil 21 A is, for example, a metal foil made of aluminum or an aluminum alloy. The negative electrode 22 is obtained by forming a negative electrode active material layer 22 B on one or both surfaces of a negative electrode foil 22 A, and the material of the negative electrode foil 22 A is, for example, a metal foil made of nickel, a nickel alloy, copper, or a copper alloy. The separator 23 is a porous and insulating film, which enables transfer of substances such as ions and an electrolytic solution while electrically insulating the positive electrode 21 and the negative electrode 22 .
The positive electrode active material layer 21 B and the negative electrode active material layer 22 B respectively cover most of the positive electrode foil 21 A and the negative electrode foil 22 A, but intentionally, neither of the layers covers one end periphery in the short axis direction of the band. Hereinafter, the part covered with no active material layer
21 B or 22 B is appropriately referred to as an active material non-covered part. In the cylindrical battery, the electrode wound body 20 is wound in such a manner that an active material non-covered part 21 C of the positive electrode and an active material non-covered part 22 C of the negative electrode are overlapped with each other with the separator 23 interposed therebetween so as to face in opposite directions.
FIG. 2 shows an example of a structure with the positive electrode 21 , the negative electrode 22 , and the separator 23 stacked before winding. The active material non-covered part 21 C (the upper hatched part in FIG. 2 ) of the positive electrode has a width denoted by A, and the active material non-covered part 22 C (the lower hatched part in FIG. 2 ) of the negative electrode has a width denoted by B. According to one embodiment, A>B is preferred, for example, A=7 (mm) and B=4 (mm). A part of the active material non-covered part 21 C of the positive electrode, protruded from one end of the separator 23 in the width direction, has a length denoted by C, and a part of the active material non-covered part 22 C of the negative electrode, protruded from the other end of the separator 23 in the width direction, has a length denoted by D. According to one embodiment, C>D is preferred, for example, C=4.5 (mm) and D=3 (mm).
The active material non-covered part 21 C of the positive electrode is made of, for example, aluminum, whereas the active material non-covered part 22 C of the negative electrode is made of, for example, copper, and thus, the active material non-covered part 21 C of the positive electrode is typically softer (has a lower Young's modulus) than the active material non-covered part 22 C of the negative electrode. Thus, according to one embodiment, A>B and C>D are more preferred, and in this case, when the active material non-covered part 21 C of the positive electrode and the active material non-covered part 22 C of the negative electrode are bent at the same pressure simultaneously from both electrode sides, the positive electrode 21 and the negative electrode 22 may be similar in the height of the bent part, measured from the tip of the separator 23 . In this case, the active material non-covered parts
21 C and 22 C are bent to appropriately overlap with each other, thus allowing the active material non-covered parts
21 C and 22 C and current-collecting plates
24 and 25 to be easily joined by laser welding. Joining according to one embodiment means joining by laser welding, but the joining method is not limited to laser welding.
For the positive electrode 21 , a section of 3 mm in width, including the boundary between the active material non-covered part 21 C and the active material covered part 21 B, is coated with an insulating layer 101 (gray region part in FIG. 2 ). Further, the whole region of the active material non-covered part 21 C of the positive electrode, opposed the active material covered part 22 B of the negative electrode with the separator interposed therebetween, is covered with the insulating layer 101 . The insulating layer 101 has the effect of reliably preventing any internal short circuit of the battery 1 if any foreign matter enters between the active material covered part 22 B of the negative electrode and the active material non-covered part 21 C of the positive electrode. In addition, the insulating layer 101 has the effect of, when an impact is applied to the battery 1 , absorbing the impact and reliably preventing the active material non-covered part 21 C of the positive electrode from being bent or short-circuited with the negative electrode 22 .
The central axis of the electrode wound body 20 has a through hole 26 formed. The through hole 26 is a hole for insertion of a winding core for assembling the electrode wound body 20 and an electrode rod for welding. The electrode wound body 20 is wound in an overlapping manner such that the active material non-covered part 21 C of the positive electrode and the active material non-covered part 22 C of the negative electrode face in the opposite directions, and thus, the active material non-covered part 21 C of the positive electrode is gathered at one (end 41 ) of the ends of the electrode wound body, whereas the active material non-covered part 22 C of the negative electrode is gathered at the other (end 42 ) of the ends of the electrode wound body 20 . For improving contact with the current-collecting plates
24 and 25 for current extraction, the active material non-covered parts
21 C and 22 C are bent, and the ends
41 and 42 serve as surfaces. The bending directions are directions from the outer edges
27 and 28 of the ends
41 and 42 toward the through hole 26 , and peripheral active material non-covered parts
21 C and 22 C that are adjacent in the wound state are bent in a manner of overlapping with each other. In this specification, the âsurfaceâ includes a flat surface or a raised part slightly raised between the grooves 43 , and the âflat surfaceâ includes not only a perfectly flat surface but also a surface with some unevenness and surface roughness to the extent that the active material non-covered part and the current-collecting plate can be joined.
When each of the active material non-covered parts
21 C and 22 C are bent so as to have an overlap, it seems possible for the ends
41 and 42 to have flat surfaces, but if no processing is performed before bending, wrinkles or voids (voids, spaces) 51 are generated at the ends
41 and 42 at the time of bending, and the ends
41 and 42 have no flat surfaces. In this regard, the âwrinklesâ or âvoidsâ are portions where the bent active material non-covered parts
21 C and 22 C are biased, thereby causing the ends 41 and 42 to have no flat surfaces. For preventing the generation of wrinkles and voids 51 , grooves 43 (see, for example, FIG. 4 B ) are formed in advance in radiation directions from the through hole 26 . The groove 43 extends from the outer edges
27 and 28 of the ends
41 and 42 to the through hole 26 in the central axis. The central axis of the electrode wound body 20 has the through hole 26 , and the through hole 26 is used as a hole into which a welding tool is inserted in the process of assembling the lithium ion battery 1 . The active material non-covered parts
21 C and 22 C have notches at the start of winding the positive electrode 21 and the negative electrode 22 near the through hole 26 . This is for keeping the through hole 26 from being closed in the case of bending toward the through hole 26 . The grooves 43 remain in the flat surfaces also after bending the active material non-covered parts
21 C and 22 C, and parts without the grooves 43 are joined (welded or the like) to the positive electrode current-collecting plate 24 or the negative electrode current-collecting plate 25 . It is to be noted that the grooves 43 as well as the flat surfaces may be joined to a part of the current-collecting plates
24 and 25 .
The detailed configuration of the electrode wound body 20 , that is, the respective detailed configuration of the positive electrode 21 , negative electrode 22 , separator 23 , and electrolytic solution will be described later.
In a common lithium ion battery, for example, a lead for current extraction is welded to each one of the positive electrode and negative electrode, but this is not suitable for high-rate discharge because of the high internal resistance of the battery and the temperature increased by heat generation of the lithium ion battery in the case of discharging. Thus, in the lithium ion battery according to one embodiment, the internal resistance of the battery is kept low by disposing the positive electrode current-collecting plate 24 and the negative electrode current-collecting plate 25 at the ends
41 and 42 , and welding at multiple points to the active material non-covered parts
21 C and 22 C of the positive electrode and negative electrode present at the ends
41 and 42 . The ends 41 and 42 are bent to form flat surfaces, which also contributes to the reduction in resistance.
FIG. 3 A and FIG. 3 B show examples of the current-collecting plates. FIG. 3 A shows the positive electrode current-collecting plate 24 , and FIG. 3 B shows the negative electrode current-collecting plate 25 . The material of the positive electrode current-collecting plate 24 is, for example, a metal plate made of a simple substance of aluminum or an aluminum alloy or a composite thereof, and the material of the negative electrode current-collecting plate 25 is, for example, a metal plate made of a simple substance of nickel, a nickel alloy, copper, or a copper alloy or a composite thereof. As shown in FIG. 3 A , the positive electrode current-collecting plate 24 has the shape of a flat fan-shaped part 31 with a rectangular band-shaped part 32 attached thereto. The fan-shaped part 31 has, near the center thereof, a hole 35 formed, and the hole 35 is located at a position corresponding to the through hole 26 .
A hatched part in FIG. 3 A is an insulating part 32 A where an insulating tape is attached to the band-shaped part 32 or an insulating material is applied thereto, and the part below the hatched part in the drawing is a connecting part 32 B to a sealing plate that also serves as an external terminal. It is to be noted that in the case of a battery structure without any metallic center pin (not shown) in the through hole 26 , the band-shaped part 32 has a low probability of coming into contact with a site with a negative electrode potential, and thus, there is no need for the insulating part 32 A. In such a case, the widths of the positive electrode 21 and negative electrode 22 can be increased by an amount corresponding to the thickness of the insulating part 32 A to increase the charge/discharge capacity.
The negative electrode current-collecting plate 25 has substantially the same shape as the positive electrode current-collecting plate 24 , but has a different band-shaped part. The band-shaped part 34 of the negative electrode current-collecting plate in FIG. 3 B is shorter than the band-shaped part 32 of the positive electrode current-collecting plate, without any part corresponding to the insulating part 32 A. The band-shaped part
CLAIMS
Claims ( 17 )
The invention claimed is:
1. A secondary battery comprising:
an electrode wound body that has a positive electrode and a negative electrode stacked with a separator interposed therebetween and has a wound structure; and
a positive electrode current-collecting plate and a negative electrode current-collecting plate, accommodated in an exterior can,
wherein the positive electrode includes a first covered part covered with a positive electrode active material layer and a positive electrode active material non-covered part on a positive electrode foil, and
the negative electrode includes a second covered part covered with a negative electrode active material layer and a negative electrode active material non-covered part on a negative electrode foil,
one or both of the positive electrode active material non-covered part and the negative electrode active material non-covered part have a surface formed by bending toward a central axis of the wound structure and overlapping each other,
the surface is joined to the positive electrode current-collecting plate or the negative electrode current-collecting plate, and
the positive electrode and the negative electrode meet 0.2â¤Zâ¤2.0, with Z=tÃm/T,
wherein a thickness of the positive electrode foil or negative electrode foil farthest from the central axis at a joined site on a positive electrode side or a joined site on a negative electrode side is denoted by t (mm), and a number of foils overlapped is denoted by m, and a thickness of the positive current-collecting plate or negative current-collecting plate is denoted by T (mm), and
wherein a part of the positive electrode active material non-covered part that faces the negative electrode with the separator interposed therebetween has an insulating layer.
2. The secondary battery according to claim 1 , wherein the number of the foils overlapped is mâ¥2 at each of the joined sites on the positive electrode side and on the negative electrode side.
3. The secondary battery according to claim 1 , wherein the surface has a groove.
4. The secondary battery according to claim 2 , wherein the surface has a groove.
5. The secondary battery according to claim 1 , wherein the surface includes a flat surface.
6. The secondary battery according to claim 1 , wherein the surface includes a raised part.
7. The secondary battery according to claim 1 , wherein at least one of ends of the active material non-covered parts of the positive electrode and negative electrode is protruded outward from the separator, and a part of the active material non-covered part protruded from an end surface of the separator has a length that meets 1.0â¤Lâ¤10.0,
wherein the length is denoted by L (mm).
8. A secondary battery comprising:
an electrode wound body that has a positive electrode and a negative electrode stacked with a separator interposed therebetween and has a wound structure; and
a positive electrode current-collecting plate and a negative electrode current-collecting plate, accommodated in an exterior can,
wherein the positive electrode includes a first covered part covered with a positive electrode active material layer and a positive electrode active material non-covered part on a positive electrode foil, and
the negative electrode includes a second covered part covered with a negative electrode active material layer and a negative electrode active material non-covered part on a negative electrode foil,
one or both of the positive electrode active material non-covered part and the negative electrode active material non-covered part have a surface formed by bending toward a central axis of the wound structure and overlapping each other,
the surface is joined to the positive electrode current-collecting plate or the negative electrode current-collecting plate, and
the positive electrode and the negative electrode meet 0.2â¤Zâ¤2.0, with Z=tÃm/T
wherein a thickness of the positive electrode foil or negative electrode foil farthest from the central axis at a joined site on a positive electrode side or a joined site on a negative electrode side is denoted by t (mm), and a number of foils overlapped is denoted by m, and a thickness of the positive current-collecting plate or negative current-collecting plate is denoted by T (mm), and
wherein
a width of the positive electrode active material non-covered part is larger than a width of the negative electrode active material non-covered part,
an end of the positive electrode active material non-covered part and an end of the negative electrode active material non-covered part is protruded outward from the separator, and
a length of a part of the positive electrode active material non-covered part protruded from one end of the separator in a width direction is larger than a length of a part of the negative electrode active material non-covered part protruded from the other end of the separator in the width direction.
9. The secondary battery according to claim 1 , wherein a material of the positive electrode current-collecting plate includes aluminum or an aluminum alloy.
10. The secondary battery according to claim 1 , wherein a material of the negative electrode current-collecting plate includes nickel, a nickel alloy, copper, a copper alloy, or a composite thereof.
11. A battery pack comprising:
the secondary battery according to claim 1 ;
a controller configured to control the secondary battery; and
an exterior body that encloses the secondary battery.
12. An electronic device comprising the secondary battery according to claim 1 .
13. An electronic device comprising the battery pack according to claim 11 .
14. An electric tool comprising the battery pack according to claim 11 ,
wherein the electric tool is configured to use the battery pack as a power supply.
15. An electric aircraft comprising:
the battery pack according to claim 11 ;
a plurality of rotor blades;
a motor that rotates each of the rotor blades;
a support shaft that supports each of the rotor blades and the motor;
a motor controller configured to control rotation of the motor; and
a power supply line that supplies power to the motor,
wherein the battery pack is connected to the power supply line.
16. The electric aircraft according to claim 15 , comprising:
a plurality of pairs of the rotor blades facing each other; and
the battery pack includes a plurality of battery packs,
wherein the plurality of pairs of rotor blades and the plurality of battery packs are equal in number.
17. An electric vehicle including the secondary battery according to claim 1 , comprising:
a conversion device that receives power supply from the secondary battery to convert the power to a driving force for the electric vehicle; and
a controller configured to perform information processing related to vehicle control, based on information on the second battery.
US17/566,056
2019-07-30
2021-12-30
Secondary battery, battery pack, electronic device, electric tool, electric aircraft, and electric vehicle
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Families Citing this family (22)
* Cited by examiner, â Cited by third party
Publication number
Priority date
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Assignee
Title
CN114649556B
( en )
*
2020-12-21
2025-05-30
å®å¾·æ¶ä»£æ°è½æºç§æè¡ä»½æéå ¬å¸
Battery cells, batteries and electrical devices
US12132227B2
( en )
2021-01-19
2024-10-29
Lg Energy Solution, Ltd.
Battery, and battery pack and vehicle comprising the same
PL4047703T3
( en )
2021-01-19
2024-04-29
Lg Energy Solution, Ltd.
Electrode terminal, cylindrical battery cell, battery pack and vehicle
KR102756042B1
( en )
2021-02-19
2025-01-21
주ìíì¬ ìì§ìëì§ì루ì
Electrode assembly, Battery, and Battery pack and Vehicle including the same
US12537229B2
( en )
2021-02-19
2026-01-27
Lg Energy Solution, Ltd.
Riveting structure of electrode terminal, and cylindrical battery cell, battery pack and vehicle including the same
CN113193274B
( en )
*
2021-04-14
2022-06-10
å½ç æ°è½(æ·±å³)ææ¯æéå ¬å¸
Battery and electronic equipment
CN117355989A
( en )
*
2021-05-27
2024-01-05
æ¾ä¸ç¥è¯äº§æç»è¥æ ªå¼ä¼ç¤¾
Joining method
EP4386969A4
( en )
*
2021-10-15
2025-05-07
LG Energy Solution, Ltd.
ELECTRODE ASSEMBLY, CYLINDRICAL BATTERY CELL, AND BATTERY PACK AND VEHICLE COMPRISING SAME
DE202022003076U1
( en )
*
2021-10-22
2024-10-10
Lg Energy Solution, Ltd.
Electrode arrangement, battery and battery pack and vehicle having such
JP7709610B2
( en )
*
2021-11-19
2025-07-16
ã¨ã«ã¸ã¼ ã¨ãã¸ã¼ ã½ãªã¥ã¼ã·ã§ã³ ãªãããã
Electrode assembly, battery, battery pack including same, and automobile
CA3219281A1
( en )
*
2021-11-19
2023-05-25
Jae-Eun Lee
Electrode assembly, battery, and battery pack and vehicle including the same
JP7772922B2
( en )
2021-11-19
2025-11-18
ã¨ã«ã¸ã¼ ã¨ãã¸ã¼ ã½ãªã¥ã¼ã·ã§ã³ ãªãããã
Electrode assembly, battery, battery pack including same, and automobile
US20250079530A1
( en )
*
2021-11-24
2025-03-06
Lg Energy Solution, Ltd.
Electrode assembly and manufacturing apparatus and method thereof, cylindrical battery including the electrode assembly, and battery pack and vehicle including the same
WO2023162530A1
( en )
*
2022-02-22
2023-08-31
æ ªå¼ä¼ç¤¾æç°è£½ä½æ
Secondary battery, battery pack, electronic device, power tool, electric aircraft, and electric vehicle
JP2025521846A
( en )
2022-07-19
2025-07-10
ã¨ã«ã¸ã¼ ã¨ãã¸ã¼ ã½ãªã¥ã¼ã·ã§ã³ ãªãããã
Cylindrical battery, battery pack and automobile
EP4525109A4
( en )
*
2022-07-19
2026-02-11
Lg Energy Solution Ltd
CYLINDRICAL BATTERY, BATTERY PACK AND VEHICLE
JPWO2024070516A1
( en )
*
2022-09-29
2024-04-04
CN115911256A
( en )
*
2022-11-04
2023-04-04
å¦é¨æ°è½è¾¾ç§ææéå ¬å¸
Cylindrical battery and electrical device containing it
CN121970160A
( en )
*
2023-12-21
2026-05-01
Skæ°è½æºæ ªå¼ä¼ç¤¾
Electrode assembly and battery cell including the electrode assembly
WO2025143146A1
( en )
*
2023-12-27
2025-07-03
ããã½ããã¯ï¼©ï½ããã¸ã¡ã³ãæ ªå¼ä¼ç¤¾
Electricity storage device and method for manufacturing electricity storage device
JP2026043682A
( en )
*
2024-08-29
2026-03-12
æ ªå¼ä¼ç¤¾å°æ¾è£½ä½æ
Method for manufacturing an energy storage device, and an energy storage device
CN120341519A
( en )
*
2025-02-25
2025-07-18
æ±è天é¹çµæºæéå ¬å¸
Roll core, full-ear cylindrical battery and power-consuming device
Citations (10)
* Cited by examiner, â Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
JP2002042769A
( en )
2000-07-25
2002-02-08
Nissan Motor Co Ltd
Secondary battery and its manufacturing method
JP3912574B2
( en )
2000-12-04
2007-05-09
æ ªå¼ä¼ç¤¾ã¦ã¢ãµéçº
Sealed battery
JP2007335156A
( en )
*
2006-06-13
2007-12-27
Honda Motor Co Ltd
Electricity storage element
JP2008166030A
( en )
2006-12-27
2008-07-17
Sanyo Electric Co Ltd
Manufacturing method of spiral electrode body, and manufacturing method of closed battery using this
JP2010010117A
( en )
2008-05-30
2010-01-14
Hitachi Vehicle Energy Ltd
Lithium secondary battery and its manufacturing method
US20110195286A1
( en )
*
2010-02-08
2011-08-11
Hitachi Vehicle Energy, Ltd.
Secondary Cell
WO2013001821A1
( en )
2011-06-28
2013-01-03
æ¥æ¬ã±ãã³ã³æ ªå¼ä¼ç¤¾
Electricity storage device and method for manufacturing electricity storage device
US20140120417A1
( en )
2012-10-30
2014-05-01
Sony Corporation
Battery, electrode, battery pack, electronic device, electric vehicle, power storage device, and power system
WO2017061066A1
( en )
2015-10-05
2017-04-13
ã½ãã¼æ ªå¼ä¼ç¤¾
Residual quantity measuring device, battery pack, electric power tool, electric-type aircraft, electric vehicle and power supply
US20190296304A1
( en )
*
2016-12-16
2019-09-26
Murata Manufacturing Co., Ltd.
Secondary battery, battery pack, electric vehicle, power storage system, power tool, and electronic device
Family Cites Families (2)
* Cited by examiner, â Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
EP2573857B1
( en )
*
2010-05-18
2016-03-02
Toyota Jidosha Kabushiki Kaisha
Nonaqueous electrolyte secondary battery, vehicle, and device using battery
JP2018163833A
( en )
*
2017-03-27
2018-10-18
ä¸æ´é»æ©æ ªå¼ä¼ç¤¾
Nonaqueous electrolyte secondary battery and manufacturing method
2020
2020-07-15
WO
PCT/JP2020/027429
patent/WO2021020119A1/en
not_active
Ceased
2020-07-15
JP
JP2021536913A
patent/JP7355109B2/en
active
Active
2020-07-15
CN
CN202080053475.0A
patent/CN114175301B/en
active
Active
2021
2021-12-30
US
US17/566,056
patent/US12255289B2/en
active
Active
Patent Citations (13)
* Cited by examiner, â Cited by third party
Publication number
Priority date
Publication date
Assignee
Title
JP2002042769A
( en )
2000-07-25
2002-02-08
Nissan Motor Co Ltd
Secondary battery and its manufacturing method
JP3912574B2
( en )
2000-12-04
2007-05-09
æ ªå¼ä¼ç¤¾ã¦ã¢ãµéçº
Sealed battery
JP2007335156A
( en )
*
2006-06-13
2007-12-27
Honda Motor Co Ltd
Electricity storage element
JP2008166030A
( en )
2006-12-27
2008-07-17
Sanyo Electric Co Ltd
Manufacturing method of spiral electrode body, and manufacturing method of closed battery using this
JP2010010117A
( en )
2008-05-30
2010-01-14
Hitachi Vehicle Energy Ltd
Lithium secondary battery and its manufacturing method
US20110195286A1
( en )
*
2010-02-08
2011-08-11
Hitachi Vehicle Energy, Ltd.
Secondary Cell
WO2013001821A1
( en )
2011-06-28
2013-01-03
æ¥æ¬ã±ãã³ã³æ ªå¼ä¼ç¤¾
Electricity storage device and method for manufacturing electricity storage device
US20140113185A1
( en )
2011-06-28
2014-04-24
Nippon Chemi-Con Corporation
Electricity storage device and method for manufacturing electricity storage device
US20140120417A1
( en )
2012-10-30
2014-05-01
Sony Corporation
Battery, electrode, battery pack, electronic device, electric vehicle, power storage device, and power system
JP2014089856A
( en )
2012-10-30
2014-05-15
Sony Corp
Cell, electrode, cell pack, electronic apparatus, electric vehicle, storage device and power system
WO2017061066A1
( en )
2015-10-05
2017-04-13
ã½ãã¼æ ªå¼ä¼ç¤¾
Residual quantity measuring device, battery pack, electric power tool, electric-type aircraft, electric vehicle and power supply
US20180203069A1
( en )
*
2015-10-05
2018-07-19
Murata Manufacturing Co., Ltd.
Residual quantity measuring device, battery pack, electric power tool, electric aircraft, electric vehicle, and power supply device
US20190296304A1
( en )
*
2016-12-16
2019-09-26
Murata Manufacturing Co., Ltd.
Secondary battery, battery pack, electric vehicle, power storage system, power tool, and electronic device
Non-Patent Citations (4)
* Cited by examiner, â Cited by third party
Title
Chinese Office Action issued Aug. 18, 2023 in corresponding Chinese Application No. 202080053475.0.
Chinese Office Action issued Mar. 4, 2024 in corresponding Chinese Application No. 202080053475.0.
International Search Report for Application No. PCT/JP2020/027429, dated Sep. 24, 2020.
Japanese Office Action issued Aug. 30, 2022 in corresponding Japanese Application No. 2021-536913.
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