Current collector plates for batteries

Abstract

Exemplary current collector plates (108, 200, 300) for a battery (100) are described herein. In one example, the current collector plate (108, 200, 300) includes a frame member (202, 302) having at least two arms (204, 304). The at least two arms are radially arranged on the frame member (202, 302) to define at least two slots (206, 306) in the frame member (202, 302). The current collector plate further includes at least two flap members (208, 308). The at least two flap members (208, 308) are coupled to an inner periphery (210, 310) of the frame member (202, 302) and positioned in the at least two slots (206, 306) without contacting the at least two arms (204, 304). Each flap member lies in a different plane than the plane in which the frame members lies.

Description

[Technical Field]

[0001] The present invention relates to a current collector plate for a battery. [Background technology]

[0002] Secondary batteries offer various advantages, including high operating voltage and high energy density per unit weight, and are therefore widely used as power sources for portable electronic devices and hybrid or electric vehicles. Secondary batteries can be classified into cylindrical, prismatic, or pouch types. Generally, cylindrical secondary batteries include an electrode assembly, a casing that houses the electrode assembly, an electrolyte injected into the casing, and a cap assembly attached to one side of the casing to prevent separation of the electrode assembly. [Brief explanation of the drawings]

[0003] The detailed description is given with reference to the accompanying drawings, in which:

[0004] [Figure 1] 1 illustrates an exploded view of a battery according to an example. [Figure 2] 1 illustrates a perspective view of a current collector plate of a battery according to an example. [Figure 3] 10 shows a cross-sectional view of another example of a current collector plate. Summary of the Invention

[0005] Conventional cylindrical secondary batteries include a jelly-roll type electrode assembly. The jelly-roll is prepared by rolling up positive and negative electrode foils or sheets with a separator between them. The positive electrode is a positive active material, such as a layered metal oxide, coated on a conductive foil, such as aluminum foil. The negative electrode is a negative active material, such as graphite, coated on a conductive foil, such as copper foil. The electrode assembly is then placed inside a casing, and a cap assembly with external terminals is attached to the casing. Additionally, conductive tabs are attached to the positive and negative electrodes to collect the current generated by the electrode assembly.

[0006] Recently, secondary batteries have been developed in which, instead of separate conductor tabs, current collector foils without an active material coating act as tabs. Once the electrode assembly is wound like a jelly roll, positive and negative current collector plates are welded to the positive and negative tabs, respectively. The electrode assembly is then placed into a pre-assembled casing with rivets on its top surface. The positive current collector plate is welded to the rivets, and the negative current collector plate is welded to the side wall of the casing to close the casing.

[0007] In existing technologies, components such as the positive and negative current collector plates are tightly packed, so variations in the dimensions of the electrode assembly can impair the overall assembly of the secondary battery. For example, if the electrode assembly is longer than the design height, the positive current collector plate may strike a rivet, preventing the negative current collector plate from physically contacting the side wall of the casing. As a result, it can be difficult to attach the negative current collector plate to the side wall of the casing. Similarly, if the electrode assembly is shorter than the design height, the negative current collector plate may strike the wall of the casing, but there may not be physical contact between the positive current collector plate and the rivet for the intended attachment.

[0008] The present subject matter describes exemplary current collector plates and batteries having such current collector plates, which may facilitate accommodating variations in the planarity of different components of the current collector plate to height tolerances of the electrode assembly.

[0009] In accordance with the present subject matter, a current collector plate of a battery includes a frame member. The frame member defines a boundary of the current collector plate. The frame member further includes at least two arms converging from an interior surface of the frame member toward a center of the frame member. The at least two arms divide an interior region of the frame member into two or more slots.

[0010] Additionally, the current collector plate includes two or more flap members coupled to an inner periphery of the frame member, the two or more flap members disposed in the two or more slots without contacting the at least two arms, and each of the two or more flap members residing in a plane different from the plane in which the frame member residing.

[0011] According to the present subject matter, the two or more flap members are welded to the electrode assembly, which is then inserted into the casing. Because the two or more flap members are connected to the frame member from only one side, the two or more flap members are configured to accommodate variations in the height of the electrode assembly. For example, to accommodate an electrode assembly height that is higher than desired, the two or more flap members can be pushed upward toward the plane of the frame member without changing the size of the casing. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present subject matter will be further described with reference to the accompanying drawings. Wherever possible, the same reference numbers are used in the figures and the following description to refer to the same or similar parts. It should be noted that the description and figures merely illustrate the principles of the present subject matter. That is, it will be understood that various arrangements incorporating the principles of the present subject matter can be devised even if not explicitly described or shown herein. Moreover, all statements herein that recite principles, aspects, and examples of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof.

[0013] The manner in which the present subject matter may be implemented is described in detail with reference to Figures 1-3. While aspects of the described subject matter may be implemented in any number of different devices, environments, and / or implementations, examples are described in the context of the following systems. Note that the drawings of the present subject matter shown herein are for illustrative purposes and are not drawn to scale.

[0014] FIG. 1 shows an exploded view of a battery 100, such as a secondary battery, according to an example. The battery 100 includes a casing 102. The casing 102 may be made of a conductive metal, such as aluminum, an aluminum alloy, or nickel-coated steel. The casing 102 depicted in FIG. 1 is formed in a cylindrical shape with a cylindrical wall 102a of a predetermined diameter. The casing 102 has a sealed end 104 and an open end (not shown).

[0015] The battery 100 further includes a jellyroll-like electrode assembly 106. The electrode assembly 106 includes a first electrode (not shown) and a second electrode (not shown), with a separator layer (not shown) interposed between the first and second electrodes. The first electrode, separator layer, and second electrode are then wound around a core (not shown).

[0016] The electrode assembly 106 is then electrically connected at one end to a current collector plate 108. The current collector plate 108 can act as a bridge component that collects and connects the current generated in the electrode assembly 106 to an external terminal. In the present subject matter, the current collector plate 108 is connected to an uncoated portion of the positive electrode, such as an electrode foil. The current collector plate 108 includes a stepped structure that facilitates accommodating variations in the height of the electrode assembly 106 without altering the remaining aspects of the battery 100. For example, when the current collector plate 108 is attached to the electrode assembly 106, only a portion of the current collector plate 108 contacts the electrode assembly 106. This portion can be compressed or deflected based on the height of the electrode assembly 106.

[0017] Further details regarding the current collector plate 108 are described in conjunction with Figures 2 and 3. Although the current collector plate 108 is depicted as a cathode plate in Figure 1, it can be understood that the current collector plate 108 may be implemented as an anode plate or as both a cathode plate and an anode plate.

[0018] Additionally, an insulating disk or gasket 110 is attached to the current collector plate 108, after which the electrode assembly 106 is inserted inside the casing 102 through the open end. The insulating disk 110 is therefore disposed between the current collector plate 108 and the inner surface of the sealed end 104 of the casing 102. The open end of the casing 102 is further sealed by a lower plate 112, thereby holding the electrode assembly 106 within the casing 102. The lower plate 112 is attached to the casing 102 in such a manner that the lower plate 112 contacts the negative electrode of the electrode assembly 106. Because the peripheral edge of the lower plate 112 is aligned with the side wall 102a of the casing 102, the upper surface of the sealed end 104 of the casing 102, and therefore the negative terminal of the battery 100, acts as the negative terminal of the battery 100. The lower plate 112 further seals the casing 102 with a sealing rubber 114 and a sealing pin 116.

[0019] Additionally, battery 100 includes a rivet 118 that is attached to the sealed end 104 of casing 102 through a rivet gasket 120. Rivet 118 is welded to the cathode current collector plate 108. As a result, rivet 118 acts as the positive terminal for battery 100. Rivet gasket 120 provides an airtight seal between rivet 118 and the sealed end 104 of casing 102. Rivet gasket 120 provides electrical insulation between the opposing terminals of battery 100.

[0020] 2 shows a perspective view of an example current collector plate 200. Although the current collector plate 200 depicted in FIG. 2 has a substantially circular shape, the current collector plate 200 may have any suitable shape based on the shape of the electrode assembly to which the electrode assembly 200 is attached. The current collector plate 200 is similar to the current collector plate 108.

[0021] The current collector plate 200 includes a frame member 202 that defines the boundary of the current collector plate 200. The frame member 202 includes at least two arms 204 that converge from an interior surface of the frame member 200 toward a center of the frame member. The at least two arms 204 are arranged radially in the frame member 200. The at least two arms 204 divide an interior region of the frame member 202 and define two or more slots 206 in the frame member 202.

[0022] Additionally, the current collector plate 200 includes two or more flap members 208. The flap members 208 are connected to an inner periphery 210 of the frame member 202. As will be apparent to one skilled in the art, the number of flap members corresponds to the number of slots in the frame member 202. In the present subject matter, the two or more flap members 208 are disposed in the two or more slots 206 without contacting at least two arms 204 of the frame member 202. In the subject matter, the two or more flap members 208 lie in a plane different from the plane in which the frame member 202 lies. For example, the plane of the two or more flap members 208 may be below the plane of the frame member 202, resulting in a step or height difference between the frame member 202 and the two or more flap members 208.

[0023] In one implementation, current collector plate 200 includes a protruding member 212 formed about the center of frame member 202. In one example, protruding member 212 fits under a hollow rivet of a battery, such as battery 100. In one example, two or more flap members 208 each lie in a different plane than the plane in which protruding member 212 lies. That is, frame member 202, two or more flap members 208, and protruding member 212 all lie in different planes relative to one another.

[0024] The above-described structure of the current collector plate 200 allows the two or more flap members 208 to be adjustable relative to the electrode assembly to which the two or more flap members 208 are attached. While the current collector plate 200 is attached to the electrode assembly, the two or more flap members 208 are welded to the uncoated portions of the electrode assembly by laser welding. In one example, a cathode current collector plate made in accordance with the present subject matter is welded to the uncoated portions of the cathode foil, and an anode current collector plate is welded to the uncoated portions of the anode foil.

[0025] For example, if the height of the electrode assembly is higher than desired, the two or more flap members 208 can be extended upward as the electrode assembly is welded to the two or more flap members 208. Such movement of the flap members 208 relative to the frame member 202 is possible due to the different planes of the flap members 208 and the frame member 202. This allows the anode current collector plate to contact the side wall of the casing for welding purposes.

[0026] 3 shows a cross-sectional view of another example current collector plate 300. Current collector plate 300 is similar to current collector plates 108 and 200. In this implementation, current collector plate 300 has a thickness ranging from about 0.4 millimeters (mm) to about 1 mm. Furthermore, current collector plate 300 may be made from an aluminum material, a stainless steel material, or a copper material.

[0027] The current collector plate 300 includes a frame member 302 having at least two arms 304. The at least two arms 304 define at least two slots 306 in an interior region of the frame member 302. In one example, the at least two arms 204 each have a width of about 2.5 millimeters (mm).

[0028] Additionally, the frame member 302 includes two or more flap members 308 that are positioned in the two or more slots 306 without contacting the arms. As described with reference to Figure 2, the two or more flap members 308 reside in a plane different from the plane of the frame member 302, and the frame member 302 includes a step or height difference between the inner periphery 310 of the frame member 302 and the two or more flap members 308.

[0029] Although aspects of the present disclosure have been described in language specific to structural features and / or methods, it should be understood that the appended claims are not limited to the particular features or methods described therein. Rather, the particular features and methods are disclosed as examples of the present disclosure.

Claims

1. A current collector plate (108, 200, 300) connected to an electrode assembly (106) of a battery (100), comprising: a frame member (202, 302) having at least two arms (204, 304); Two or more flap members (208, 308); Including, the at least two arms (204, 304) converge from an inner periphery (210, 310) of the frame member (202, 302) toward a center of the frame member (202, 302) to define two or more slots (206, 306) in the frame member (202, 302); the two or more flap members (208, 308) are coupled to an inner periphery (210, 310) of the frame member (202, 302) and are disposed in the two or more slots (206, 306) without contacting the at least two arms (204, 304); The two or more flap members (208, 308) each lie in a plane different from the plane in which the frame member (202, 302) lies.

2. The current collector plate (108, 200, 300) of claim 1, wherein the plane of the two or more flap members (208, 308) lies below the plane of the frame member (202, 302).

3. The current collector plate (108, 200, 300) of claim 2, wherein the current collector plate (108, 200, 300) includes a step between each of the two or more flap members (208, 308) and the frame member (202, 302).

4. The current collector plate (108, 200, 300) of claim 1, wherein the at least two arms (204, 304) are radially arranged on the frame member (202, 302).

5. The current collector plate (108, 200, 300) of claim 1, wherein the current collector plate (108, 200, 300) includes a protruding member (212, 312) formed about a center of the frame member (202, 302).

6. The current collector plate (108, 200, 300) of claim 5, wherein each of the two or more flap members (208, 308) lies in a plane different from the plane in which the protruding member (212, 312) lies.

7. The current collector plate (108, 200, 300) of claim 1, wherein the current collector plate (108, 200, 300) is made from an aluminum material, a stainless steel material, or a copper material.

8. The current collector plate (108, 200, 300) of claim 1, wherein the current collector plate (108, 200, 300) has a thickness in the range of about 0.4 millimeters (mm) to about 1 mm.

9. A battery (100), a casing (102); an electrode assembly (106) including at least a positive electrode and a negative electrode, the electrode assembly (106) being disposed within the casing (102); a current collector plate (108, 200, 300) connected to one of the positive and negative electrodes; Including, The current collector plate (108, 200, 300) a frame member (202, 302) having at least two arms (204, 304); Two or more flap members (208, 308); Including, the at least two arms (204, 304) converge from an inner periphery (210, 310) of the frame member (202, 302) toward a center of the frame member (202, 302) to define two or more slots (206, 306) in the frame member (202, 302); the two or more flap members (208, 308) are coupled to an inner periphery (212, 312) of the frame member (202, 302) and are disposed in the two or more slots (206, 306) without contacting the at least two arms (204, 304); each of the two or more flap members (208, 308) is in a plane different from the plane in which the frame member (202, 302) is in; The battery (100) is arranged inside the casing (102) after the electrode assembly (106) is connected to the current collector plates (108, 200, 300) by the two or more flap members (208, 308).

10. 10. The battery (100) of claim 9, wherein the plane of the two or more flap members (208, 308) lies below the plane of the frame member (202, 302).

11. 11. The battery (100) of claim 10, wherein the current collector plate (108, 200, 300) includes a step between each of the two or more flap members (208, 308) and the frame member (202, 302).

12. 10. The battery (100) of claim 9, wherein the electrode assembly (106) is a jelly-roll type electrode assembly.

13. 10. The battery (100) of claim 9, wherein the current collector plate (108, 200, 300) includes a protruding member (212, 312) formed about a center of the frame member (202, 302).

14. 14. The battery (100) of claim 13, wherein each of the two or more flap members (208, 308) lies in a different plane than the plane in which the protruding member (212, 312) lies.

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