Accumulator cell

Abstract

The present application relates to a power storage single cell including an electrode body having a jelly-roll formed by winding a positive electrode sheet and a negative electrode sheet with a separator interposed therebetween, a current collector plate, a single cell case, and an electrolyte. The positive electrode sheet and the negative electrode sheet each have a current collector foil and an active material layer. The current collector foil has a main region in which the active material layer is provided and an end region in which the active material layer is not provided. A plurality of tabs in the end region are arranged in a manner that a covered region in which a portion of the covered layer end is formed and an exposed region in which a remaining portion of the layer end is exposed are formed. The current collector plate is connected to the covered region.

Description

[0001] This application is a divisional application of patent application No. 202410608548.8, filed on May 16, 2024, entitled "Energy Storage Single Battery". Technical Field

[0002] This disclosure relates to a single-cell battery. Background Technology

[0003] Japanese Patent Application Publication No. 10-162854 discloses a cylindrical battery comprising an electrode group consisting of a spiral body formed by winding strip-shaped positive and negative electrode plates separated by a separator, a circular current collector, a battery casing, and an electrolyte. The positive and negative electrode plates have conductive edges protruding outward from their vertical ends, and these conductive edges are connected to the current collector. Summary of the Invention

[0004] In the so-called tabless type single-cell rechargeable battery described in Japanese Patent Application Publication No. 10-162854, it is required that the tabs of the current collector foil be reliably connected to the current collector plate. Furthermore, especially during high-speed charging and discharging, electrolyte flows out of the electrode body, so there may be insufficient electrolyte in the electrode body.

[0005] The purpose of this disclosure is to provide a single-cell battery capable of suppressing electrolyte deficiency in the electrode body while ensuring the connection between the current collector foil and the current collector plate.

[0006] A single-cell battery according to one aspect of this disclosure comprises: an electrode body having a positive electrode plate, a negative electrode plate, and a separator, wherein the electrode body is formed by winding the positive electrode plate and the negative electrode plate together with respect to the separator; a current collector plate connected to the electrode body; a single-cell housing housing the electrode body and the current collector plate; and an electrolyte contained within the single-cell housing, wherein each of the positive and negative electrode plates has a current collector foil and an active material layer disposed on the surface of the current collector foil, and the current collector foil has a current collector foil having an active material layer disposed on the surface of the current collector foil. The electrode body has an active material layer and a main region arranged to overlap each other in the radial direction, and an end region formed on the outer side of the main region in the axial direction of the electrode body without the active material layer. The active material layer includes a layer end formed by the axial end. The end region has a plurality of tabs that are separated from each other in the circumferential direction of the electrode body and bent relative to the main region. The plurality of tabs are arranged to form a covered region that covers a portion of the layer end and an exposed region that exposes the remaining portion of the layer end. The current collector is connected to the covered region.

[0007] The above and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0008] Figure 1 This is a schematic cross-sectional view of a single battery in one embodiment of the present disclosure.

[0009] Figure 2 It is a plan view that roughly shows the electrode body.

[0010] Figure 3 This is a schematic front view showing the positive electrode sheet before winding.

[0011] Figure 4 This is a plan view that roughly shows a modified example of the electrode body.

[0012] Figure 5 This is a plan view that roughly shows a modified example of the electrode body.

[0013] Figure 6 This is a plan view that roughly shows a modified example of the electrode body.

[0014] Figure 7 This is a plan view that roughly shows a modified example of the electrode body. Detailed Implementation

[0015] In embodiments of this disclosure, reference is made to the accompanying drawings. Furthermore, in the drawings referred to below, the same reference numerals are used to denote the same or equivalent components.

[0016] Figure 1 This is a partial cross-sectional view schematically showing a single battery 1 in one embodiment of the present disclosure. The single battery 1 is preferably mounted in a vehicle.

[0017] like Figure 1 As shown, the single-cell battery 1 includes an electrode body 100, a single-cell housing 200, an external terminal 300, a positive current collector 410, a negative current collector 420, an insulating member 500, and an electrolyte (not shown).

[0018] The electrode body 100 has a positive electrode plate 110, a negative electrode plate 120, and a separator 130. The electrode body 100 is a wound body formed by the positive electrode plate 110 and the negative electrode plate 120 being wound around the core A with the separator 130 in between.

[0019] Figure 3 This is a simplified front view showing the positive electrode sheet before winding. (Example) Figure 1 as well as Figure 3As shown, the positive electrode sheet 110 has a positive current-collecting foil 112 and a positive active material layer 114. Furthermore, in Figure 3 In the middle, the positive electrode active material layer 114 is shown in a dot pattern.

[0020] The positive electrode current collector foil 112 is made of metal such as aluminum. The positive electrode current collector foil 112 has a main region 112a and an end region 112b.

[0021] The main region 112a is the region in the positive electrode current collector foil 112 where the positive electrode active material layer 114 is disposed. For example... Figure 1 As shown, the main region 112a is located radially ( ) of the electrode body 100 Figure 1 The left and right directions are configured to overlap.

[0022] The end region 112b is the region in the positive electrode current collector foil 112 where the positive electrode active material layer 114 is not provided. For example... Figure 1 As shown, the end region 112b is formed along the axial direction of the electrode body 100. Figure 1 The outer side of the main region 112a in the vertical direction (in the middle) Figure 1 (The upper side of the middle).

[0023] The end region 112b has a plurality of tabs 112b1 that are circumferentially separated from each other on the electrode body 100 (see reference). Figure 3 ).like Figure 1 As shown, each tab 112b1 is bent relative to the main region 112a. Specifically, each tab 112b1 is tilted inward in the radial direction. The upper surface of each tab 112b1 forms a generally flat surface. A positive current collector plate 410 is connected to each tab 112b1 by welding or the like.

[0024] The negative electrode sheet 120 has a negative electrode current collector foil 122 made of metal such as copper and a negative electrode active material layer 124 disposed on the surface of the negative electrode current collector foil 122.

[0025] The structure of the negative electrode current collector foil 122 is substantially the same as that of the positive electrode current collector foil 112. Therefore, the description of the negative electrode current collector foil 122 is simplified. That is, the negative electrode current collector foil 122 has a main region 122a on which the negative electrode active material layer 124 is disposed, and an outer side of the main region 122a formed in the axial direction ( Figure 1 The end region 122b (lower side) has multiple tabs that are circumferentially separated from each other, each tab tilting radially inward. A negative current collector plate 420 is connected to each tab by welding or the like.

[0026] A separator 130 is disposed between the positive electrode plate 110 and the negative electrode plate 120. More specifically, the separator 130 is disposed only between the main region 112a of the positive electrode plate 110 and the main region 122a of the negative electrode plate 120, which are radially adjacent to each other. The separator 130 is made of an insulating material, allowing ion permeation.

[0027] The single-cell housing 200 houses the electrode body 100. An electrolyte (not shown) is contained within the single-cell housing 200. The single-cell housing 200 is sealed. The single-cell housing 200 is made of a metal such as aluminum. The single-cell housing 200 has a cylindrical portion 210, a top wall 220, and a bottom wall 230.

[0028] The cylindrical portion 210 surrounds the outer peripheral surface of the electrode body 100.

[0029] The top wall 220 is connected to the upper end of the cylindrical portion 210. A through hole for inserting an external terminal 300 is formed in the center of the top wall 220.

[0030] The bottom wall 230 is connected to the lower end of the cylindrical portion 210. More specifically, the bottom wall 230 is connected to the lower end of the cylindrical portion 210 via an insulating member 235. The bottom wall 230 is in contact with the negative current collector 420.

[0031] An external terminal 300 is formed above the top wall 220. In this embodiment, the external terminal 300 constitutes the external terminal of the positive electrode. In addition, the single battery casing 200 constitutes the external terminal of the negative electrode.

[0032] The insulating member 500 insulates the single battery housing 200 from the external terminal 300. The insulating member 500 has an upper insulating portion 510 and a lower insulating portion 520.

[0033] The upper insulating portion 510 is provided on the upper surface of the top wall 220. The upper insulating portion 510 is located between the upper surface of the top wall 220 and the external terminal 300.

[0034] The lower insulating portion 520 is disposed on the lower surface of the top wall 220. The lower insulating portion 520 is located between the positive current collector 410 and the single battery casing 200.

[0035] Figure 2 This is a schematic plan view of the electrode body. Furthermore, the lower surface of the electrode body 100 has a structure that substantially corresponds to the upper surface of the electrode body 100; therefore, the following description will take the structure of the upper surface of the electrode body 100 as an example.

[0036] like Figure 2As shown, multiple tabs 112b1 are arranged such that they have a covered region R10 and an exposed region R20. The covered region R10 is covered with the end points 114a and 124a of each active material layer 114 and 124 in the axial direction (see reference). Figure 1 The exposed area R20 is the area that exposes the remaining portions of the layer ends 114a and 124a (the area outside the area covered by the covered area R10).

[0037] exist Figure 2 In the example shown, the plurality of tabs 112b1 are configured to form a plurality (6) of coated regions R10 arranged at intervals in the circumferential direction of the electrode body 100. Each coated region R10 extends radially from the outer end of the radially inclined electrode body 100 toward the inner end of the radially inclined electrode body 100. The radially inner end of each coated region R10 is located at the midpoint between the outer end and the inner end of the radially inclined electrode body 100.

[0038] The exposed area R20 includes annular exposed areas R22 that are connected in a ring shape in the circumferential direction of the electrode body 100. The annular exposed areas R22 are formed inside the radially covered area R10. Furthermore, the shapes of the exposed areas R20 can be different on the upper and lower surfaces of the electrode body 100. For example, the area of ​​the exposed area R20 on the lower surface of the electrode body 100 can be formed to be larger than the area of ​​the exposed area R20 on the upper surface of the electrode body 100.

[0039] As explained above, in the single battery 1 of this embodiment, the connection between each current collector foil 112, 122 and each current collector plate 410, 420 in the covered area R10 is ensured, and since the electrolyte flowing out from the electrode body 100 during high-speed charging and discharging is re-immersed in the electrode body 100 through the exposed area R20, the insufficiency of electrolyte in the electrode body 100 is suppressed.

[0040] Furthermore, during the manufacture of the single battery 1, when the electrode body 100 is housed in the single battery housing 200 and an electrolyte is supplied to the single battery housing 200, the electrolyte is effectively impregnated in the electrode body 100 through the exposed area R20.

[0041] In the above embodiments, such as Figure 4 as well as Figure 5 As shown, the covered area R10 can also be shaped to extend from the outer end of the radial electrode body 100 to the inner end. In this design, the degree of freedom in selecting the connection points between the covered area R10 and each current collector 410, 420 is increased.

[0042] In addition, such as Figure 6 as well as Figure 7As shown, the coated region R10 can also include annular coated regions R12 that are connected in a ring shape in the circumferential direction. In other words, the plurality of tabs 112b1 can also be arranged such that annular coated regions R12 are formed. In this scheme, the outflow of electrolyte from the electrode body 100 during high-speed charging and discharging is effectively blocked by the annular coated regions R12, and the electrolyte flowing out of the electrode body 100 is re-impregnated into the electrode body 100 through the exposed region R20. Therefore, the insufficiency of electrolyte in the electrode body 100 is more reliably suppressed.

[0043] exist Figure 6 In the example shown, the annular coated region R12 is formed inside the radially exposed region R20. The annular coated region R12 covers the core A. In this design, the area of ​​the exposed region R20 is ensured to be relatively large, thus allowing the electrolyte to flow smoothly into the electrode body 100 through the exposed region R20.

[0044] exist Figure 7 In the example shown, the annular coating region R12 is formed outside the radially exposed region R20. In this design, the exposed region R20 is formed on the side of the core A in the electrode body 100, which is prone to stress concentration and heat buildup, thus facilitating the flow of electrolyte into the electrode body 100.

[0045] Those skilled in the art will understand that the above-described embodiments are specific examples of the following solutions.

[0046] [Option 1]

[0047] A single-cell rechargeable battery, comprising:

[0048] An electrode body having a positive electrode plate, a negative electrode plate, and a separator, and being composed of a wound body formed by winding the positive electrode plate and the negative electrode plate with the separator in between;

[0049] A current collector, the current collector being connected to the electrode body;

[0050] A single-cell housing, the single-cell housing housing the electrode body and the current collector; and

[0051] Electrolyte, which is contained within the single battery casing.

[0052] The positive electrode plate and the negative electrode plate each have:

[0053] Current collector foil; and

[0054] An active material layer is disposed on the surface of the current collector foil.

[0055] The current collector foil has the following characteristics:

[0056] The main region, wherein the active material layer is disposed and arranged to overlap each other radially in the electrode body; and

[0057] The end region is formed outside the main region along the axial direction of the electrode body and is not provided with the active material layer.

[0058] The active material layer includes layer ends formed by the axially extending ends.

[0059] The end region has a plurality of tabs that are circumferentially separated from each other and bent relative to the main region of the electrode body.

[0060] The plurality of tabs are configured such that they form a covered area that covers a portion of the end of the layer and an exposed area that exposes the remaining portion of the end of the layer.

[0061] The current collector is connected to the covered area.

[0062] In this single-cell battery, the connection between the current collector foil and the current collector plate in the covered area is ensured, and since the electrolyte flowing out from the electrode body during high-speed charging and discharging is re-immersed in the electrode body through the exposed area, the insufficiency of electrolyte in the electrode body is suppressed.

[0063] [Option 2]

[0064] According to the single battery described in Scheme 1

[0065] The exposed area includes annular exposed areas that are connected in a ring shape in the circumferential direction.

[0066] [Option 3]

[0067] According to the single battery described in Scheme 2

[0068] The annular exposed area is formed inside the covered area in the radial direction.

[0069] In this scheme, the impregnation of the electrolyte from the radial inside to the outside is promoted.

[0070] [Option 4]

[0071] According to the single battery described in Scheme 1

[0072] The covered area includes annular covered areas that are connected in a ring shape in the circumferential direction.

[0073] In this design, the outflow of electrolyte from the electrode body during high-speed charging and discharging is effectively blocked by the annular coating area, and the electrolyte flowing out of the electrode body is re-immersed in the electrode body through the exposed area. Therefore, the insufficiency of electrolyte in the electrode body is more reliably suppressed.

[0074] [Option 5]

[0075] According to the single battery described in Scheme 4

[0076] The annular covered area is formed inside the exposed area in the radial direction.

[0077] In this design, the area of ​​the exposed region is ensured to be relatively large, thus allowing the electrolyte to flow smoothly into the electrode body through the exposed region.

[0078] [Option 6]

[0079] According to the single battery described in Scheme 4

[0080] The annular covered area is formed outside the exposed area in the radial direction.

[0081] In this design, an exposed area is formed on the core side of the electrode body, where stress concentration and heat accumulation are prone to occur, thus making the flow of electrolyte into the electrode body smoother.

[0082] Embodiments of the present invention have been described, but should be considered illustrative rather than restrictive in all respects. The scope of the invention is defined by the claims and is intended to include all modifications within the meaning and scope of the claims.

Claims

1. A single-cell rechargeable battery, comprising: An electrode body, wherein the electrode body is formed by winding a positive electrode sheet and a negative electrode sheet with a separator between them; A negative current collector plate, wherein the negative current collector plate is connected to the electrode body; A single-cell housing, the single-cell housing housing the electrode body and the negative current collector; and Electrolyte, which is contained within the single-cell casing. The single battery casing has a bottom wall. The bottom wall is in contact with the negative electrode current collector. The positive electrode plate and the negative electrode plate each have: Current collector foil; and An active material layer is disposed on the surface of the current collector foil. The current collector foil has the following characteristics: The main region, wherein the active material layer is disposed; and The end region, wherein the active material layer is not provided, The active material layer includes a layer end formed by the axial ends of the electrode body. The end region has multiple tabs bent relative to the main region. The plurality of tabs are configured such that they form a covered area that covers a portion of the end of the layer and an exposed area that exposes the remaining portion of the end of the layer. The negative electrode current collector is connected to the covered area. The coated area includes annular coated areas that are connected in a ring shape in the circumferential direction of the electrode body.

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