Cylindrical secondary cell and method of its manufacture

Abstract

To provide an electrode lead plate for a secondary cell that is highly reliable and efficient in manufacture.SOLUTION: There is provided an electrode lead plate (6) for a cylindrical secondary cell, comprising a terminal part and an electrode roll that comprises a conductive sheet. The electrode lead plate (6) comprises: an inner contact region (6c) configured to be arranged in direct electrical contact with the terminal part; an outer contact region (6e) configured to be arranged in direct electrical contact with the conductive sheet, where the outer contact region (6e) radially surrounds the inner contact region (6c); and a fuse region (6d) arranged between the inner contact region (6c) and the outer contact region (6e), the fuse region (6d) being adapted to break when a predetermined current passes through the fuse region (6d).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure generally relates to cylindrical secondary batteries and methods for manufacturing cylindrical secondary batteries and components thereof. The present disclosure further relates to electrode lead plates and terminal portions for cylindrical secondary batteries.

[0002] Tackling climate change is driving demand for rechargeable batteries, for example to enable the electrification of transportation and to supplement renewable energy. Currently, lithium-ion batteries are becoming increasingly popular. They represent a type of rechargeable battery in which lithium ions move from the negative electrode to the positive electrode during discharge and back during charging.

[0003] As the demand for rechargeable batteries increases, there is an increasing focus on production speed. To achieve efficient production of rechargeable batteries, the design of the batteries as well as their manufacturing processes can be optimized.

[0004] Rechargeable batteries, often referred to as secondary batteries, typically include one or more secondary cells electrically connected together. Summary of the Invention

[0005] The present invention has been made in view of the above and other considerations. It is an object of the present disclosure to provide a secondary battery that is highly reliable and has a reduced number of components and whose assembly is simplified.

[0006] According to a first aspect of the present disclosure, there is provided an electrode lead plate for a cylindrical secondary battery. The electrode lead plate includes a terminal portion and an electrode roll including a conductive sheet. The electrode lead plate is configured to be disposed in direct electrical contact with both the terminal portion and the conductive sheet. The electrode lead plate includes an inner contact region configured to be disposed in direct electrical contact with the terminal portion and an outer contact region configured to be disposed in direct electrical contact with the conductive sheet. The outer contact region radially surrounds the inner contact region.

[0007] The electrode lead plate is in direct electrical contact with the terminal portion and the conductive sheet, so that the terminal portion and the conductive sheet are in efficient and reliable contact with each other. Direct electrical contact means direct electrical and physical contact. The electrode lead plate can be one single component electrically coupled between the conductive sheet and the terminal portion. In other words, the electrode lead plate can be the only component electrically coupled between the conductive sheet and the terminal portion. This reduces the number of components of the cylindrical secondary battery and reduces the number of steps required for its manufacture.

[0008] The electrode lead plate may have the general shape of a circular disk, the outer contact area may be annular, and the inner contact area may be circular.

[0009] The electrode lead plate may include a fuse region disposed between the inner contact region and the outer contact region. In other words, current flowing from the conductive sheet of the electrode roll to the terminal portion passes through the fuse region. The fuse region may be adapted to break, i.e., burn out, when a predetermined current passes through the fuse region. In this way, the electrode lead plate not only provides a current path between the conductive sheet and the terminal portion, but also provides a fuse function.

[0010] The fuse region may be annular. The outer contact region may surround the fuse region, which may surround the inner contact region. The outer contact region, fuse region, and inner contact region may be concentric.

[0011] The fuse region may comprise a current conducting area that is selectively reduced by a recess formed in the electrode lead plate. Such a recess may be formed on one or both end surfaces of the electrode lead plate. The recess may provide the fuse region in a simple and space-efficient manner. The recess may surround the inner contact region.

[0012] The fuse area may include at least one through-hole formed through the electrode lead plate such that at least one fuse element is formed in the electrode lead plate. The fuse element forms a current conducting area. Such at least one through-hole may provide a well-defined fuse area that can be precisely tailored to rupture at a specific current.

[0013] The fuse region may include both depressions and through-holes. For example, there may be three elongated through-holes forming three bridges between the inner and outer regions. The bridges thus form the fuse element. The bridges may include depressions. The through-holes may be circular. Alternatively, there may be two or four through-holes forming two or four bridges, respectively.

[0014] The inner contact area may be configured, for example, so that a terminal in the form of a pin can be attached thereto by welding or soldering. The inner contact area may, for example, be flat and dimensioned to fit the end of the terminal.

[0015] The inner contact area may be recessed relative to the outer contact area, in other words, the inner and outer contact areas may extend in parallel planes spaced apart from one another, which planes may be parallel to the overall extension of the electrode lead plate and spaced apart along an axis perpendicular to both planes.

[0016] When the inner contact area is recessed, the terminal portion can extend through the outer contact area and be attached to the cylindrical secondary battery by deformation of the terminal portion. The terminal portion can be a rivet. The rivet can include a factory rivet head disposed on the outside of the cylindrical secondary battery to provide an external terminal. The rivet can further include a shop rivet head disposed on the inside of the cylindrical secondary battery. The shop rivet head can be accommodated by the recessed inner contact area.

[0017] The inner and outer contact regions 6c, 6e may be radially separated from one another. Radial separation allows for placement of a fuse region between the inner and outer contact regions 6c, 6e. Furthermore, such radial separation allows for the inner contact region 6c to be recessed relative to the outer contact region 6e.

[0018] The electrode lead plate may include a number of electrolyte flow holes. The electrolyte flow holes may allow electrolyte to flow through the electrode lead plate. The electrolyte flow holes may be arranged in a pattern on the electrode lead plate that allows the electrode lead plate to be welded to the conductive sheet with a plurality of non-intersecting, linear weld lines extending across the electrode lead plate. The weld lines may be, for example, laser weld lines.

[0019] A weld line extending across the electrode lead plate, i.e., from one side to the other, can be useful for firmly attaching the electrode lead plate to the conductive sheet of the electrode roll. Furthermore, compared to a radial weld line extending between the outer edge of the electrode lead plate and the center point of the electrode lead plate, a weld line extending across the electrode lead plate can be more cost-effective to manufacture.

[0020] The pattern can be configured such that a plurality of essentially parallel weld lines can be positioned adjacent to one another across the electrode lead plate. The weld lines can be positioned adjacent to one another essentially evenly, i.e., at an essentially regular mutual distance. Such weld lines can result in a uniform force distribution at the interface between the electrode lead plate and the conductive sheet.

[0021] The plurality of essentially parallel weld lines described above may be referred to as a first set of weld lines. The pattern may be configured such that a second set of weld lines may be disposed on the electrode lead plate, the second set corresponding to the first set but extending at an angle relative to the first set. Additionally, the pattern may be configured such that a third set of weld lines may be disposed on the electrode lead plate, the second set extending at an angle relative to the first and second sets. The angle between angularly adjacent sets may be approximately 60 degrees.

[0022] The pattern may include multiple electrolyte flow hole groups, each of which includes at least one flow hole. The electrolyte flow hole groups may be arranged such that a linear weld line can be positioned between two adjacent electrolyte flow hole groups, where at least four weld lines may extend across the electrode lead plate, with one electrolyte flow hole group disposed between each weld line. For example, there may be five or six such weld lines.

[0023] A pattern can be disposed on the outer contact region. The pattern can include electrolyte flow holes positioned essentially equidistant from one another on the outer contact region. The electrolyte flow holes can be positioned essentially equidistant from one another and from delimits of the outer contact region.

[0024] The pattern may have a six-pointed star configuration. Such a configuration may allow for multiple weld lines as described above and may allow for essentially equidistant electrolyte flow holes. There may be 12 electrolyte flow holes. The six-pointed star pattern may also be referred to as a pattern including an inner hexagonal pattern of electrolyte flow holes and an outer hexagonal pattern of electrolyte flow holes, the inner and outer patterns rotated approximately 30 degrees relative to each other.

[0025] The electrolyte flow holes may be arranged in alternate patterns on the electrode lead plate that allow the electrode lead plate to be welded to the conductive sheet with multiple, non-intersecting, straight weld lines extending across the electrode lead plate.

[0026] An alternative pattern may involve the electrolyte flow holes being arranged in an inner square pattern and an outer square pattern, rotated approximately 45 degrees relative to one another. In another example, the electrolyte flow holes are arranged in an inner pentagonal pattern and an outer pentagonal pattern. Thus, there may be eight or ten electrolyte flow holes.

[0027] According to a second aspect of the present disclosure, there is provided a method for manufacturing a cylindrical secondary battery. Such a cylindrical secondary battery may include an electrode roll including an electrode lead plate, a terminal portion, and a conductive sheet. The method includes disposing the electrode lead plate in direct electrical and physical contact with the terminal portion and the conductive sheet.

[0028] The advantages and additional steps of such a method will be apparent to those skilled in the art upon reviewing the above-described first aspect of the present disclosure, which relates to an electrode lead plate for a cylindrical secondary battery. For example, the method may involve riveting a rivet and welding an electrode lead plate. The method of the second aspect may, but need not, involve an electrode lead plate according to the first aspect. For example, the method need not involve an electrode lead plate with inner and outer contact regions, as described in connection with the first aspect.

[0029] According to a third aspect of the present disclosure, there is provided a use of an electrode lead plate for connecting a conductive sheet of an electrode roll of a cylindrical secondary battery to a terminal portion of the cylindrical secondary battery, the use involving placing the electrode lead plate in direct electrical and physical contact with the conductive sheet and the terminal portion.

[0030] The advantages and further steps of such use will be apparent to those skilled in the art upon review of the above-described first aspect of the present disclosure, which relates to an electrode lead plate for a cylindrical secondary battery. The use of the third aspect may, but need not, involve the electrode lead plate of the first aspect. For example, the use need not involve an electrode lead plate with inner and outer contact regions as described in connection with the first aspect.

[0031] According to a fourth aspect of the present disclosure, a terminal for a cylindrical secondary battery is provided. The cylindrical secondary battery includes an electrode lead plate. The terminal includes a first terminal end portion that forms an external terminal of the cylindrical secondary battery, and a second terminal end portion configured to be disposed in direct electrical contact with the electrode lead plate. The terminal end portions can be positioned at both ends of the terminal portion.

[0032] The terminal portion can be attached to the electrode lead plate and function as an external terminal of the cylindrical secondary battery, thereby sealing the cylindrical secondary battery.

[0033] The terminal may comprise an electrically insulating means surrounding at least a portion of the terminal.

[0034] The terminal may include a head portion and a shaft portion, and the electrical insulating means may surround the shaft portion. The terminal may be a rivet having a factory rivet head and a rivet shaft adapted to extend through the wall of the cylindrical secondary battery and form a shop rivet head after riveting. The rivet may be advantageous for tightly and cost-effectively sealing the cylindrical secondary battery. The electrical insulating means may be cost-effectively provided as a separate component that collectively electrically insulates the rivet from the wall of the cylindrical secondary battery.

[0035] The electrical insulating means may comprise a first portion extending between the head portion and the cylindrical secondary battery, more precisely between the head portion and the wall of the cylindrical secondary battery, and may further comprise a second portion surrounding the shaft portion.

[0036] In addition, the electrical insulating means may include a third portion extending along the electrode lead plate. More precisely, the third portion may extend inside the cylindrical secondary battery between the electrode lead plate and the wall of the cylindrical secondary battery.

[0037] The first portion of the electrical insulating means may have the form of a disk, for example a circular disk, with a central through hole for the terminal portion. Thus, the first portion of the electrical insulating means may be annular. The second portion of the electrical insulating means may be cylindrical. The third portion of the electrical insulating means may be annular. Such portions of the electrical insulating means may be cost-effective to produce and assemble.

[0038] The first and second portions of the electrical insulating means may be separate components. Such components may be particularly cost-effective to produce and assemble. The third portion of the electrical insulating means may also be a separate component. The first, second, and third portions may be provided not only to electrically insulate the terminal portion from the cylindrical housing of the cylindrical secondary battery, but also to provide a seal that prevents leakage of the electrolyte.

[0039] According to a fifth aspect of the present disclosure, there is provided a terminal arrangement for a cylindrical secondary battery. The cylindrical secondary battery includes an electrode lead plate and an electrode roll. The terminal arrangement includes the electrode lead plate and the above-described terminal portion. Therefore, the terminal arrangement can include the above-described electrical insulation means.

[0040] According to a sixth aspect of the present disclosure, there is provided a method for manufacturing a cylindrical secondary battery. The cylindrical secondary battery includes a terminal portion and an electrode lead plate. The method includes placing the terminal portion in direct electrical contact with the electrode lead plate. The terminal portion and the electrode lead plate may be of the types described above. Accordingly, the terminal portion may be a pin or a rivet. The method may include welding the electrode lead plate to an inner end surface of the pin or rivet, i.e., to a rivet shop head.

[0041] According to a seventh aspect of the present disclosure, there is provided a use of a terminal part for forming an external terminal of a cylindrical secondary battery. The terminal part is disposed in direct electrical contact with an electrode lead plate of the cylindrical secondary battery. The terminal part, the electrode lead plate, and the cylindrical secondary battery may be of the type described above. Accordingly, the terminal part may be a pin or a rivet.

[0042] According to an eighth aspect of the present disclosure, a cylindrical secondary battery is provided. The cylindrical secondary battery includes an electrode roll including a conductive sheet, an electrode lead plate configured to be disposed in direct electrical contact with the conductive sheet, and a terminal portion that forms an external terminal of the cylindrical secondary battery and is configured to be disposed in direct electrical contact with the electrode lead plate. The electrode roll may include another conductive sheet that is in electrical contact with another external terminal of the cylindrical secondary battery. The electrode lead plate and terminal portion may be of the type described above.

[0043] According to a ninth aspect of the present disclosure, there is provided a method for manufacturing the cylindrical secondary battery of the preceding paragraph, the method comprising: disposing an electrode lead plate in direct electrical contact with the terminal portion and the conductive sheet.

[0044] Embodiments disclosed herein are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings, in which like reference numerals refer to corresponding parts throughout. [Brief explanation of the drawings]

[0045] [Figure 1]FIG. 1 shows a first end of a cylindrical secondary battery in cross section. [Figure 2] FIG. 2 is an enlarged cutaway view of FIG. [Figure 3] FIG. 3 shows the electrode lead plate. [Figure 4] FIG. 4 shows a second embodiment of the electrode lead plate. [Figure 5] FIG. 5 shows an exploded view of a third embodiment of an electrode lead plate and an electrode roll. [Figure 6] FIG. 6 shows a fourth embodiment of the electrode lead plate. [Figure 7] FIG. 7 shows the electrode lead plate of FIG. 4 with a first set of weld lines. [Figure 8] FIG. 8 shows the electrode lead plate of FIG. 4 with first and second sets of weld lines. [Figure 9] FIG. 9 shows a fifth embodiment of the electrode lead plate. DETAILED DESCRIPTION OF THE INVENTION

[0046] Embodiments of the present disclosure will now be described more fully below. However, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided as examples so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0047] FIG. 1 shows a first embodiment of a cylindrical secondary battery 1 (hereinafter referred to as a battery) comprising a cylindrical housing 2 having a first housing end 2a (top end in FIG. 1) and an opposite second housing end 2b (not shown). The cylindrical housing 2 may also be referred to as a can. An electrode roll 3 is contained within the cylindrical housing 2. The first housing end 2a may be integrally formed with the cylindrical housing 2 (as illustrated in FIG. 1), and the second housing end 2b may be formed by a separate second housing end lid (not shown), or vice versa. Both housing ends 2a, 2b may alternatively be formed by their respective lids.

[0048] The first and second (to be briefly described) embodiments of the battery 1 relate to a type of battery 1 that has both a positive terminal 4 and a negative terminal 5 at one and the same end (the top end in FIG. 1 ) of the cylindrical secondary battery 1. The first housing end 2a is provided with a central terminal through-hole 2c for the positive terminal 4. The negative terminal 5 is electrically connected to the cylindrical housing 2. More precisely, the negative terminal 5 is formed by the top surface of the cylindrical housing 2 that surrounds the terminal through-hole 2c. Thus, the entire cylindrical housing 2 (except for the positive terminal 4 at the top end) can be the negative terminal.

[0049] A cylindrical secondary battery having both terminals 4, 5 at one end may offer advantages for electrically connecting the battery to a load. The conductors electrically connecting the terminals to the load may be positioned on the same end of the battery, i.e., the terminal end. The opposite end of the battery, i.e., the electrolyte fill end, may be dedicated to electrolyte filling and venting. The electrolyte fill end will not be described in detail in this disclosure. Overpressure may develop within the battery during operation, particularly upon a fault in the battery or a load connected to the battery. Such a fault may require the release of gas and / or electrolyte from the battery, and it may be advantageous to direct the released gas and / or electrolyte away from the conductors.

[0050] For example, in an electric vehicle, multiple batteries may be positioned in a low position with the terminal ends facing upward and the electrolyte fill ends facing downward. In the event of a fault, for example, resulting from a faulty electric vehicle charger or a faulty battery, any release of gas and / or electrolyte from the electrolyte fill end(s) will advantageously be directed downward toward the ground beneath the vehicle.

[0051] The electrode roll 3 comprises first and second conductive sheets 3a, 3b and a separating means (not shown). The separating means may also be called a separator. The conductive sheets 3a, 3b and the separating means are wound to form a circular cylindrical roll defining a central channel 3c. The sheets 3a, 3b are coated with an electrode coating, and upon assembly of the battery 1, the cylindrical housing 2 is filled with an electrolyte. The electrolyte may flow through the central channel 3c or conduit. The coatings on the conductive sheets 3a, 3b function as the cathode and anode, respectively. The cathode, anode, and electrolyte provide electrochemical energy storage. This principle is known per se, and the electrode roll 3 is commonly referred to as a jelly roll.

[0052] The sheets 3a, 3b of the electrode roll 3 are axially offset relative to one another and each have an end section that is not covered with an electrode coating. In Figure 1, only one end of the electrode roll 3 is shown, at which end a first conductive sheet 3a protrudes axially from the electrode roll 3. At the opposite end (not shown) of the electrode roll 3, a second conductive sheet 3b protrudes axially. The second electrode roll 3b is indicated diagrammatically in Figure 1 by a dashed arrow.

[0053] In Figure 1, the upper end of the first conductive sheet 3a is not coated with an electrode coating. Similarly, although not shown, the lower end of the second conductive sheet 3b is also not coated with an electrode coating. In this way, each end of the electrode roll 3 can be efficiently electrically connected to each assigned terminal 4, 5 of the battery 1. This design is known per se and is commonly referred to as a tabless battery.

[0054] In this disclosure, only the connection between one of the conductive sheets 3a, 3b and one of the terminals 4, 5 is described in detail. The other of the conductive sheets 3a, 3b is electrically connected to the other of the terminals 4, 5 in a manner not described in detail herein.

[0055] 1 and 2, the battery 1 includes an electrode lead plate 6 disposed at the upper end of the electrode roll 3. The electrode lead plate 6 is in direct electrical contact with the first conductive sheet 3a, more precisely, with the uncoated end section of the first conductive sheet 3a. The electrode lead plate 6 is in direct electrical and physical contact with the first conductive sheet 3a. The electrode lead plate 6 can be attached, for example, welded, for example, laser welded, to the first conductive sheet 3a.

[0056] The battery 1 further includes a terminal portion 4. In the embodiment of the present disclosure, the terminal portion is rotationally symmetric about its longitudinal central axis (not illustrated). The terminal portion 4 extends through the first housing end 2a and has an outer end, i.e., first end 4a, and an inner end, i.e., second end 4b. The outer end 4a of the terminal portion 4 may form a first terminal of the battery 1. As shown in FIG. 1 , the terminal portion 4 is in direct electrical contact with the electrode lead plate 6. The terminal portion 4 is in direct electrical and physical contact with the electrode lead plate 6. More precisely, the inner end 4b of the terminal portion 4 is in direct electrical contact with the electrode lead plate 6. The inner end 4b may be attached, e.g., welded, e.g., laser welded, to the electrode lead plate 6.

[0057] As best shown in Figure 2, the terminal part 4 may be provided with an electrical insulating means 7 surrounding at least a portion of the terminal part 4. In the embodiment of Figures 1 and 2, the terminal part 4 has the shape of a rivet with a head portion 4c, i.e., a so-called factory rivet head, and a shaft portion 4d, i.e., a rivet shaft. In the embodiment of Figures 1 and 2, the electrical insulating means is rotationally symmetric. As illustrated, the electrical insulating means 7 surrounds the rivet shaft 4d. The electrical insulating means may be called a rivet gasket.

[0058] More specifically, the electrical insulating means 7 may comprise or consist of a first part 7a arranged between the factory rivet head 4c and the first housing end 2a, and a second part 7b surrounding the rivet shaft 4d. The first part 7a may be an annular disk having an outer diameter larger than that of the factory rivet head 4c. The inner diameter of the first part 7a may correspond to the diameter of the rivet shaft 4d. Thus, the first part 7a may electrically insulate the factory rivet head 4c, or more precisely, the inner surface of the factory rivet head 4c (i.e., facing the battery 1), from the first housing end 2a.

[0059] The rivet shaft 4d extends through a through-hole (terminal through-hole 2c) in the first housing end 2a and is electrically insulated from the through-hole by a second portion 7b of the electrical insulation means 7. In the embodiment of Figures 1 and 2, the second portion 7b is circularly cylindrical.

[0060] During the manufacture of the battery 1, the rivet 4 is riveted and thus plastically deformed, resulting in a portion of the rivet shaft 4d being radially expanded, see in particular Figure 2. The rivet shaft 4d is deformed to form a so-called shop rivet head 4e, which prevents the rivet 4 (which may be called a terminal rivet) from being pulled out of the through hole in the first housing end 2a.

[0061] 2, the electrical insulation means 7 may include a third portion 7c disposed between the shop rivet head 4e and the first housing end 2a. Additionally, the third portion 7c may extend along the upper surface of the electrode roll 3 inside the first housing end 2a to electrically insulate the electrode lead plate 6 from the first housing end 2a. The third portion 7c may be an annular disk having an outer diameter corresponding to the outer diameter of the electrode lead plate 6 and an inner diameter corresponding to the diameter of the rivet shaft 4d.

[0062] FIG. 3 shows the electrode lead plate 6 of FIGS. 1 and 2 in more detail. The electrode lead plate 6 of FIG. 3 (and FIGS. 4 to 6) can be used in cylindrical secondary batteries and with terminal portions of designs other than those described herein. The electrode lead plate 6 of the first embodiment is configured to be in direct electrical contact with the conductive sheet 3a of the electrode roll 3 and to be disposed in direct electrical contact with the terminal portion 4. The electrode roll can be a tabless electrode roll. The terminal portion 4 can form an external terminal of the battery 1.

[0063] The electrode lead plate 6 in Figure 3 has a first end surface 6a and an opposite second end surface 6b. When assembled, the first end surface 6a faces away from the electrode roll 3, and the second end surface 6b faces the electrode roll 3. In Figure 3 (and in Figures 1 and 2 when the electrode lead plate 6 is attached to such a battery 1), the first end surface 6a is the upper surface and the second end surface 6b is the lower surface.

[0064] The electrode lead plate 6 of Figure 3 includes an inner contact area 6c and an outer contact area 6e. The outer contact area includes a plurality of electrolyte flow holes 6g, which will be described below. In this example, the battery 1 is circularly cylindrical, and the electrode lead plate 6 has the general shape of a circular disk. The inner contact area 6c is configured to be placed in direct electrical contact with the terminal portion 4, and the outer contact area 6e is configured to be placed in direct electrical contact with the first conductive sheet 3a (see Figure 2). The inner contact area 6c is circular, and the outer contact area 6e is circularly annular.

[0065] The fuse region 6d is disposed between the inner contact region 6c and the outer contact region 6e. In a first embodiment, the fuse region 6d comprises three elongated through-holes forming three fuse elements 6f in the form of bridges. The bridges 6f conduct current between the outer contact region 6e and the inner contact region 6c. Thus, the bridges 6f collectively define a current-conducting area that conducts current between the outer contact region 6e and the inner contact region 6c. The current-conducting area can be dimensioned so that the fuse region 6d interrupts a predetermined value of current. Thus, if the current exceeds the predetermined value, the bridges 6f melt, i.e., burn out. Each bridge 6f can be provided with a recess to reduce the current-conducting area. Such recesses or notches are illustrated in FIG. 3 as relatively thick lines connecting the elongated through-holes, and thus the recesses extend across the bridges 6f.

[0066] In other words, the width of the bridge 6f (when viewed in plan view of the upper surface 6a or the lower surface 6b) can be adapted by the size of the elongated through-holes, and the thickness of the bridge can be reduced by the recesses.

[0067] As is apparent from FIGS. 1-3, in the first embodiment of the battery 1 and electrode lead plate 6, the inner contact area 6c is recessed relative to the outer contact area 6e. The annular outer contact area 6a is disposed in a first plane, and the circular inner contact area 6c is disposed in a second plane parallel to the first plane. Thus, the bridge 6f extends both radially and axially, connecting the two planes, i.e., the inner contact area 6c and the outer contact area 6e. Thus, the bridge 6f functions to provide a fuse function and to position the inner contact area 6c axially at a distance from the outer contact area 6e. Additionally, the through-holes forming the bridges can function as electrolyte flow holes.

[0068] 2, the recessed lead plate 6 facilitates the use of rivets as the terminal elements 4. The shop head 4e will occupy some space within the battery 1, and this space is provided by the electrode lead plate 6 due to the recessed inner contact area 6c. The rivet shop head 4e and inner contact area 6c can be positioned within the central channel 3c of the electrode roll 3.

[0069] 4 shows an electrode lead plate 6 according to a second embodiment. The electrode lead plate 6 of the second embodiment differs from that of the first embodiment in that the inner and outer contact areas 6c, 6e are positioned in the same plane. Thus, the electrode lead plate has the form of a circular, flat disk.

[0070] A second embodiment of the battery 1, not shown herein, includes the electrode lead plate 6 of FIG. 4. In such a battery, the terminal element 4 may be a pin, i.e., a structure including a head portion 4c (pin head) and a shaft portion 4d (pin shaft). The shaft portion 4d of the terminal element 4 according to the second embodiment may be axially shorter than the rivet shaft of the first embodiment. As will become apparent from a combined consideration of FIGS. 2 and 4, the shaft portion 4d may extend from the head portion 4c through an electrical insulating means 7 and terminate at the upper surface 6a of the electrode lead plate 6. During manufacturing, the end face of the shaft portion 4d may be welded to the electrode lead plate 6, more precisely, to the inner contact region 6c. The electrical insulating means may be called a pin gasket.

[0071] The electrode lead plate 6 according to the second embodiment (FIG. 4) comprises a fuse area 6d that essentially corresponds to the fuse area of ​​the first embodiment (FIG. 3). However, the bridges 6f of the second embodiment do not extend both axially and radially, but only radially, i.e., in the same plane as the disk. Furthermore, the bridges of the second embodiment do not comprise recesses. In a further embodiment (not shown), the bridges 6f of the electrode lead plate 6 corresponding to those of FIG. 4 may be provided with recesses to reduce the current conduction area.

[0072] 5 shows a third embodiment of an electrode lead plate 6 and an electrode roll 3 to which the electrode lead plate 6 can be attached. The electrode roll 3 shown in the perspective view of FIG. 5 corresponds to the electrode roll 3 shown in FIGS. 1 and 2.

[0073] The electrode lead plate 6 of the third embodiment corresponds to that of the first embodiment (FIG. 3) except for the fact that the through holes forming the bridges 6f are circular instead of elongated. The electrode lead plate 6 of the third embodiment comprises a recess, but alternative embodiments may not have a recess.

[0074] FIG. 6 shows a fourth embodiment of the electrode lead plate 6. The electrode lead plate of FIG. 6 corresponds to the electrode lead plate of FIG. 3, but does not have a through-hole in the fuse region 6d and does not have an electrolyte flow hole 6g. Therefore, the current conduction area of ​​the fuse region 6d is reduced only by the depression. In FIG. 6, the depression is shown as a circle located in the fuse region 6d.

[0075] FIG. 7 shows the electrode lead plate 6 of FIG. 4, illustrating a first set of weld lines 6h, and also showing that the electrolyte flow holes 6g may be arranged in a pattern having the form of a six-pointed star.

[0076] The electrolyte flow holes 6g may be arranged in a pattern on the electrode lead plate 6 that allows the electrode lead plate 6 to be welded to the conductive sheet 3a of the electrode roll by a plurality of non-intersecting, straight weld lines 6h. A first set of such weld lines, consisting of six weld lines, is illustrated in FIG.

[0077] In FIG. 7, the electrolyte flow holes 6g can be considered to be assigned to five separate electrolyte flow hole groups. A single linear weld line 6h extends across the electrode lead plate 6 between each electrolyte flow hole group. Specifically, referring to the orientation of FIG. 7, the topmost electrolyte flow hole 6g belongs to the first electrolyte flow hole group. Four electrolyte flow holes 6g located at essentially the same height on the electrode lead plate 6 belong to the second electrolyte flow hole group. Two electrolyte flow holes 6g located on the left and right sides of the inner contact area 6c belong to the third electrolyte flow hole group. The fourth electrode flow hole group corresponds to the second electrolyte flow hole group, and finally, the bottommost electrolyte flow hole 6g belongs to the fifth electrolyte flow hole group.

[0078] The through holes in fuse region 6d, if present, may be considered part of the third group of electrolyte flow holes.

[0079] 8 illustrates a second set of weld lines 6i that are identical to the first set of weld lines 6h, but that are disposed at an angle α of approximately 60 degrees relative to the first set of weld lines 6h. As can be seen from FIG. 8, it is further possible to apply a third set of weld lines (not shown) that are disposed at an angle of approximately 60 degrees relative to the second set of weld lines 6i.

[0080] In embodiments of the electrode lead plate 6 that include electrolyte flow holes 6g, the electrolyte flow holes 6g may be arranged in a pattern having the form of a six-pointed star or a six-ray star. In other words, if twelve electrolyte flow holes 6g were connected by imaginary lines drawn from each adjacent electrolyte flow hole 6g to the next around the circumference of the electrode lead plate 6, a six-pointed star would be formed. Such a pattern may provide evenly positioned electrolyte flow holes 6g that are beneficial for electrolyte distribution and may also leave room for continuous weld lines that are linear and evenly spaced across the electrode lead plate.

[0081] Figure 9 shows a fifth embodiment of an electrode lead plate 6 having electrolyte flow holes 6g arranged in an alternative pattern. It should be understood that the pattern of Figure 9 is also applicable to the other electrode lead plate embodiments shown herein (Figures 3, 4, 5, and 6).

[0082] The alternative, or second, pattern of Figure 9 can be described as having electrolyte flow holes 6g arranged in an inner square pattern and an outer square pattern. The inner and outer square patterns are rotated approximately 45 degrees relative to one another. Again, a first set of non-intersecting, straight weld lines 6h is illustrated. It should be understood that a second set of non-intersecting, straight weld lines can also be applied (compare Figure 8). In the embodiment of Figure 9, the angle between the two sets can be approximately 90 degrees.

[0083] It should be understood that still alternative patterns may involve inner and outer pentagonal patterns of electrolyte flow holes 6g following the same principles.

[0084] Next, a method for manufacturing a cylindrical secondary battery will be described. Such a method may involve welding electrode lead plates 6 to an electrode roll 3. Laser welding may be used, and a first set of welding lines 6i may be applied, as illustrated in Figure 7. A second set of welding lines 6h and a third set of welding lines may also be applied.

[0085] The electrical insulation means 7 (rivet / pin gasket) and the terminal portion 4 (rivet / pin) can be attached to the cylindrical housing 2 separately. For example, the terminal portion 4 can be placed on a table with the shaft portion 4d facing upward. Next, the first portion 7a and the second portion 7b of the electrical insulation means 7 can be threaded onto the shaft portion 4d. These portions 7a and 7b can be provided as a single joined part or as low-cost separate parts. The cylindrical housing 2 is then aligned with its first housing end 2a facing the table and threaded onto the shaft portion 4d, so that the shaft portion 4d can pass through the terminal through-hole 2c. Next, the third portion 7c of the electrical insulation means 7 is threaded onto the shaft portion 4d, so that the third portion 7c rests against the inner surface of the first housing end 2a.

[0086] In the embodiment where the terminal portion 4 is a rivet, it is now riveted to form a shop rivet head 4e.

[0087] Next, the electrode roll 3 with the electrode lead plate 6 is introduced into the cylindrical housing 2 through the second housing end 2b, and the electrode roll 3 is aligned with the electrode lead plate 6 facing the table. Then, the inner contact area 6c of the electrode lead plate 6 is attached to the terminal portion 4 (the inner end surface of the shop rivet head 4e or the inner end surface of the pin shaft 4d). For example, the inner contact area 6c of the electrode lead plate 6 can be welded to the terminal portion 4, and the welding can be performed through the central channel 3c.

[0088] The method may further comprise electrically connecting a second conductive sheet 3b to the cylindrical housing 2 and closing the second housing end 2b in a manner not described herein.

[0089] The coating on the first conductive sheet 3a of the electrode roll 3 can form the cathode material, and the coating on the second conductive sheet 3b can form the anode material. Typically, the cathode conductive sheet of a secondary battery comprises aluminum (aluminum in American English), so the first conductive sheet 3a can be made of aluminum. Typically, the anode-side conductive sheet of a secondary battery comprises copper or steel, so the second conductive sheet 3b can be copper or steel. References to metals listed herein include their alloys. For example, copper should be interpreted as including copper alloys, i.e., alloys primarily comprising copper. Similarly, steel should be interpreted as including nickel-plated steel.

[0090] Because it can be advantageous to use the same metal throughout the entire current path, particularly in batteries containing electrolytes, the cylindrical housing 2 is preferably made of the same metal as the second conductive sheet 3b. Accordingly, the cylindrical housing 2 can be made of copper or steel. This provides the advantage that the cylindrical housing 2 can be designed with thinner walls compared to aluminum cylindrical housings, since copper and steel have higher tensile strengths than aluminum. Another advantage is that both copper and steel have higher melting points than aluminum, which can increase the safety of the battery 1.

[0091] As can be seen from the above and from the accompanying drawings, the inner and outer contact regions 6c, 6e of the electrode lead plate 6 can be separate regions. In this embodiment, the inner contact region 6c is radially separated from the outer contact region 6e, see particularly FIGS. 3 and 4. As seen in a plan view of the electrode lead plate 6, the inner and outer contact regions 6c, 6e do not overlap. Therefore, the inner and outer contact regions 6c, 6e do not overlap in the radial direction. The radial separation of the inner and outer contact regions 6c, 6e allows for the placement of a fuse region. The radial separation of the inner and outer contact regions 6c, 6e allows for the inner contact region 6c to be recessed relative to the outer contact region 6e.

[0092] From the above, and as is further apparent from Figures 1 and 2 in particular, in this embodiment, inner contact area 6c is disposed in direct electrical contact with terminal portion 4, but is not disposed in direct electrical contact with conductive sheet 3a. Outer contact area 6e is disposed in direct electrical contact with conductive sheet 3a, but is not disposed in direct electrical contact with terminal portion 4. Modifications and other variations of the described embodiments will occur to those skilled in the art having the benefit of the teachings presented in the foregoing description and associated drawings. Accordingly, it should be understood that embodiments are not limited to the specific example embodiments described in this disclosure, and that modifications and other variations are intended to be included within the scope of this disclosure.

[0093] For example, a cylindrical secondary battery is shown as a circular cylinder. However, other cross sections are contemplated, such as a rounded square or rounded rectangular cross section. Additionally, the anode and cathode may be interchangeable.

[0094] Furthermore, although specific terms may be employed herein, they are used in a generic and descriptive sense only, and not for purposes of limitation. Thus, those skilled in the art will recognize numerous variations on the described embodiments that would still fall within the scope of the appended claims. As used herein, the terms "comprise" or "include" do not exclude the presence of other elements or steps. Furthermore, although individual features may be included in different claims (or embodiments), these may, in some cases, be advantageously combined, and the inclusion of different claims (or embodiments) does not imply that a particular combination of features is not advantageous and / or feasible. Additionally, a reference to the singular does not exclude a plurality. Finally, reference numerals in the claims are provided merely as a clarifying example and should not be construed as limiting the scope of the claims in any way.

Claims

1. An electrode lead plate (6) for a cylindrical secondary battery (1) comprising a terminal portion (4) and an electrode roll (3) comprising a conductive sheet (3a), wherein the electrode lead plate (6) comprises: an inner contact area (6c) adapted to be placed in direct electrical contact with said terminal portion (4); an outer contact area (6e) adapted to be placed in direct electrical contact with said conductive sheet (3a), wherein said outer contact area (6e) radially surrounds said inner contact area (6c); a fuse area (6d) arranged between said inner contact area (6c) and said outer contact area (6e), said fuse area (6d) being adapted to rupture when a predetermined current passes through said fuse area (6d); An electrode lead plate (6).

2. 2. The electrode lead plate (6) of claim 1, wherein the fuse region (6d) comprises a current conducting area reduced by a recess formed in the electrode lead plate (6).

3. 3. The electrode lead plate (6) according to claim 1 or 2, wherein the fuse region (6d) comprises at least one through hole formed through the electrode lead plate (6) so that at least one fuse element (6f) is formed in the electrode lead plate (6), the fuse element (6f) forming a current conducting area.

4. The electrode lead plate (6) according to any one of claims 1 to 3, wherein the inner contact area (6c) is recessed relative to the outer contact area (6e).

5. The electrode lead plate (6) according to any one of claims 1 to 4, comprising a plurality of electrolyte flow holes (6g).

6. A method for manufacturing a cylindrical secondary battery (1) comprising an electrode roll (3) comprising the electrode lead plate (6) according to any one of claims 1 to 5, a terminal portion (4), and a conductive sheet (3a), the method comprising: - The electrode lead plate (6) is arranged in direct electrical contact with the terminal portion (4) and the conductive sheet (3a). A method comprising:

7. 6. Use of the electrode lead plate (6) according to any one of claims 1 to 5 for connecting a conductive sheet (3a) of an electrode roll (3) of a cylindrical secondary battery (1) to a terminal portion (4) of the cylindrical secondary battery (1), wherein the electrode lead plate (6) is arranged in direct electrical contact with the conductive sheet (3a) and the terminal portion (4).

8. A terminal portion (4) for a cylindrical secondary battery (1) having an electrode lead plate (6), wherein the terminal portion (4) comprises: a first terminal end (4a) forming the external terminal of the cylindrical secondary battery (1); a second terminal end (4b) adapted to be placed in direct electrical contact with said electrode lead plate (6); a head portion (4c), a shaft portion (4d), - electrical insulating means (7) surrounding at least said shaft portion (4d); A terminal portion (4).

9. 9. The terminal portion (4) according to claim 8, wherein the electrical insulating means (7) comprises a first portion (7a) extending between the head portion (4c) and the cylindrical secondary battery (1), and a second portion (7b) surrounding the shaft portion (4d).

10. 10. The terminal (4) according to claim 9, wherein the first portion (7a) and the second portion (7b) are two separate portions.

11. The terminal portion (4) according to any one of claims 8 to 10, wherein the shaft portion (4d) is adapted to extend through a terminal through-hole (2c) in the housing (2) of the cylindrical secondary battery (1).

12. A terminal arrangement (10) for a cylindrical secondary battery (1) comprising an electrode lead plate (6) and an electrode roll (3), wherein the terminal arrangement (10) comprises a terminal portion (4) according to any one of claims 8 to 11 and the electrode lead plate (6).

13. A method for manufacturing a cylindrical secondary battery (1) including the terminal portion (4) according to any one of claims 8 to 11 and an electrode lead plate (6), wherein the method includes: - placing said terminals (4) in direct electrical contact with said electrode lead plates (6); and optionally - welding the terminal portion (4) to the electrode lead plate (6); A method comprising:

14. Use of the terminal portion (4) according to any one of claims 8 to 11 for forming an external terminal (4a) of a cylindrical secondary battery (1), wherein the terminal portion (4) is arranged in direct electrical contact with an electrode lead plate (6) of the cylindrical secondary battery (1).

15. A cylindrical secondary battery (1), an electrode roll (3) provided with a conductive sheet (3a), an electrode lead plate (6) according to any one of claims 1 to 6; a terminal portion (4) that forms an external terminal of the cylindrical secondary battery (1) and is configured to be placed in direct electrical contact with the electrode lead plate (6); A cylindrical secondary battery (1) comprising:

16. A cylindrical secondary battery (1), an electrode roll (3) provided with a conductive sheet (3a), an electrode lead plate (6) adapted to be placed in direct electrical contact with said conductive sheet (3a); a terminal (4) according to any one of claims 8 to 11, and A cylindrical secondary battery (1) comprising:

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