Electrode laminate and battery

Abstract

To provide an electrode laminate in which a fixation member on a side surface part is less easily removed, and a battery having the electrode laminate.SOLUTION: In an electrode laminate 12 of the present disclosure, a fixation member 11 including a cured resin is arranged in at least one side surface part. In the electrode laminate, the fixation member is formed of at least two partial fixation members 11a arranged separately from one another with a space 11b in between. A battery 10 of the present disclosure includes the electrode laminate 12 and a laminate film 13 for sealing the electrode laminate.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to an electrode laminate and a battery.

Background Art

[0002] In secondary batteries such as lithium-ion batteries, an electrode laminate may be used. In such an electrode laminate, in order to prevent displacement of each layer, etc., a technology has been developed in which a fixing member containing a curable resin is provided on the side surface portion of the electrode laminate.

[0003] For example, Patent Document 1 discloses a method for manufacturing an all-solid-state battery including a flat laminate-type electrode body (electrode laminate), an exterior body made of a laminate film that houses the laminate-type electrode body, and a resin protection member (fixing member) formed on the side surface of the laminate-type electrode body.

[0004] Further, Patent Document 1 discloses using a resin material having photocurability or thermosensitivity as the protection member.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] A fixing member containing a curable resin may peel off from the electrode laminate, and as a result, there is a problem that the function as a fixing member cannot be sufficiently exhibited.

[0007] An object of the present disclosure is to provide an electrode laminate in which a fixing member disposed on a side surface portion is difficult to peel off, and a battery having such an electrode laminate.

Means for Solving the Problems

[0008] The present inventors have found that the above problems can be solved by the following means. <Aspect 1> An electrode laminate in which a fixing member containing a curable resin is disposed on at least one side surface portion, wherein the fixing member is composed of two or more partial fixing members that are spaced apart from each other. Electrode laminate. <Aspect 2> The electrode laminate according to Aspect 1, which satisfies the following relational expression: Thickness of the fixing member ≤ (1 / width of the partial fixing member) × 100. <Aspect 3> The electrode laminate according to Aspect 1 or 2, wherein the thickness of the fixing member is 50 μm or more and 5 mm or less. <Aspect 4> The electrode laminate according to any one of Aspects 1 to 3, and A laminate film that seals the electrode laminate A battery having the same.

Advantages of the Invention

[0009] According to the present disclosure, it is possible to provide an electrode laminate in which a fixing member disposed on a side surface portion is difficult to peel off, and a battery having such an electrode laminate.

Brief Description of the Drawings

[0010]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present disclosure will be described in detail. Note that the present disclosure is not limited to the following embodiments and can be implemented with various modifications within the scope of the gist of the disclosure.

[0012] 《Electrode laminate》 In the electrode laminate of the present disclosure, a fixing member containing a curable resin is disposed on at least one side surface portion. In the electrode laminate of the present disclosure, the fixing member is composed of two or more partial fixing members that are spaced apart from each other.

[0013] The present inventors considered that one of the causes of the fixing member containing the curable resin peeling off from the electrode laminate is due to the stress generated along with the curing shrinkage of the curable resin.

[0014] Regarding this, the present inventors have found that by configuring the fixing member from two or more partial fixing members that are spaced apart from each other, it is possible to suppress the fixing member containing the curable resin from peeling off from the electrode laminate. Although not intending to be bound by any theory, this is presumably because by providing a portion on the side surface portion of the electrode laminate where the fixing member is not disposed, the stress generated along with the curing shrinkage of the curable resin can be relaxed.

[0015] Hereinafter, with reference to FIG. 1, the electrode laminate 12 of the present disclosure will be described. Note that the dimensional relationships (length, width, thickness, etc.) in FIG. 1 and other drawings do not reflect the actual dimensional relationships. FIG. 1 is a schematic view of the electrode laminate 12 of the present disclosure. The shape of the electrode laminate 12 is not particularly limited. For example, as shown in FIG. 1, it may have a top surface portion, a bottom surface portion facing the top surface portion, and four side surface portions connecting the top surface portion and the bottom surface portion. Further, in the electrode laminate 12 of the present disclosure, a fixing member 11 containing a curable resin is disposed on at least one side surface portion.

[0016] In the present disclosure, the "electrode laminate" means a laminate constituting one or more unit cells. Here, this "unit cell" may be composed of a laminate of a positive electrode current collector layer, a positive electrode active material layer, an electrolyte layer (separator layer), a negative electrode active material layer, and a negative electrode current collector layer.

[0017] The fixing member 11 may be disposed on two or more side surfaces of the electrode laminate 12. In particular, fixing members may be disposed on a pair of opposing side surfaces of the electrode laminate 12, and other members such as current collecting terminals may be disposed on the remaining pair of side surfaces. In this case, the effect of preventing displacement of the electrodes by the fixing member 11 is improved, and it becomes easier to prevent short circuits due to the intrusion of conductive foreign matter and damage due to external impact.

[0018] The curable resin is not particularly limited, and examples thereof include photocurable resins such as ultraviolet curable resins and electron beam curable resins, and thermosetting resins. The curable resin may be a radical polymerizable resin, a cationic polymerizable resin, or a combination thereof.

[0019] FIG. 2 is a schematic side view of the electrode laminate 12 of the present disclosure. As shown in FIG. 1 and FIGS. 2(a) and (b), the fixing member 11 is composed of two or more partial fixing members 11a arranged at an interval 11b from each other. The number of partial fixing members may be 3 or more, 4 or more, or 5 or more, and may be 10 or less, 8 or less, 6 or less, 5 or less, or 4 or less.

[0020] Examples of the method of arranging the fixing member 11 in this way include applying a curable resin to the side surface of the electrode laminate at intervals, or applying a curable resin to the side surface of the electrode laminate without intervals and then removing the resin adhering to the portions where intervals are desired.

[0021] The width Wa of the partial fixing member 11a may be 10 mm or more, 50 mm or more, 80 mm or more, 90 mm or more, or 100 mm or more, and may be 200 mm or less, 150 mm or less, 130 mm or less, 120 mm or less, 110 mm or less, or 100 mm or less.

[0022] The width Wb of the interval 11b may be 0.1 mm or more, 0.5 mm or more, 1 mm or more, 2 mm or more, or 3 mm or more, and may be 10 mm or less, 7 mm or less, 5 mm or less, 4 mm or less, or 3 mm or less.

[0023] The thickness T of the fixing member 11 may be 50 μm or more and 5 mm or less. This thickness T may be 100 μm or more, 500 μm or more, 750 μm or more, or 1 mm or more, and may be 4 mm or less, 3 mm or less, 2 mm or less, or 1 mm or less. When this thickness T is large, it is easy to prevent electrode displacement and short circuits due to the mixing of conductive foreign matter. When this thickness T is small, the loss of the energy density of the battery can be reduced, and the stress generated due to the curing shrinkage of the curable resin can be easily suppressed. Note that this thickness T may be the average thickness of the entire fixing member 11.

[0024] The thickness T of the fixing member 11 and the width Wa of the partial fixing member 11a may satisfy the following relational expression: The thickness T of the fixing member 11 ≤ (1 / the width Wa of the partial fixing member) × 100.

[0025] That is, the larger the width Wa of the partial fixing member, the thinner the thickness T of the fixing member 11 may be.

[0026] As a method for adjusting the thickness T of the fixing member 11, for example, a method of adjusting the viscosity when applying the curable resin for forming the fixing member 11 can be mentioned.

[0027] The length of the fixing member 11 in the stacking direction of the electrode laminate 12 may be smaller than the thickness of the electrode laminate 12. By adopting such a configuration, an increase in the thickness of the battery 10 of the present disclosure can be suppressed. Therefore, when the batteries 10 are stacked and constrained to form a battery module, the fixing member 11 can be prevented from interfering with the voltage equalization of the batteries 10.

[0028] 《Battery》 Hereinafter, with reference to FIG. 3, the battery 10 of the present disclosure will be described. FIG. 3 is a schematic plan view showing an example of the battery 10 of the present disclosure viewed in plan from the stacking direction of the electrode laminate 12.

[0029] As shown in FIG. 3, the battery 10 of the present disclosure includes the electrode laminate 12 of the present disclosure and a laminate film 13 that seals the electrode laminate 12.

[0030] 〈Electrode laminate〉 The electrode laminate 12 functions as a power generation element of the battery. For the electrode laminate 12, reference can be made to the above description regarding the electrode laminate of the present disclosure.

[0031] 〈Laminate film〉 The laminate film 13 optionally winds the electrode laminate 10 and seals the electrode laminate 12. The laminate film 13 may have a welding layer and a metal layer. For example, the electrode laminate 12 can be sealed by welding the welding layers together and / or the welding layer and a current collecting terminal 15 described later. The material of the welding layer may be, for example, a resin that can be welded by heat.

[0032] As shown in FIG. 3, the battery 10 of the present disclosure may further include a current collecting terminal 15 electrically connected to the current collecting foil 14 of the electrode laminate 12, and the laminate film 13 may wind the electrode laminate 12 and the current collecting terminal 15 to seal the electrode laminate 12 together with the current collecting terminal 15.

[0033] 〈Current collecting foil〉 The current collector foil 14 may extend from a side surface portion of the electrode laminate 12 where the fixing member 11 is not disposed. The current collector foil 14 may be a bundle of portions of the positive current collector in the electrode laminate 12 where no other layers are laminated, and a bundle of portions of the negative current collector in the electrode laminate 12 where no other layers are laminated.

[0034] 〈Current Collector Terminal〉 The current collector terminal 15 may be electrically connected to the current collector foil 14. The material of the current collector terminal 15 is not particularly limited as long as it has a current collecting function. For example, it can be the same metal material as the positive current collector and the negative current collector.

[0035] The method of joining the current collector terminal and the current collector foil is not particularly limited, but a method of joining by ultrasonic waves is exemplified.

[0036] The method of welding the laminate film to the current collector terminal is not particularly limited, but a method of thermal welding is exemplified.

[0037] The battery of the present disclosure may be a liquid battery or a solid battery. Regarding the present disclosure, the "solid battery" means a battery that uses at least a solid electrolyte as an electrolyte. Therefore, the solid battery may use a combination of a solid electrolyte and a liquid electrolyte as the electrolyte. Further, the solid battery of the present disclosure may be an all-solid battery, that is, a battery that uses only a solid electrolyte as an electrolyte.

[0038] The battery of the present disclosure may be a lithium-ion secondary battery. Examples of the use of the battery include power sources for vehicles such as hybrid vehicles (HEV), plug-in hybrid vehicles (PHEV), electric vehicles (BEV), gasoline vehicles, and diesel vehicles. In particular, it is preferably used as a driving power source for hybrid vehicles (HEV), plug-in hybrid vehicles (PHEV), or electric vehicles (BEV). Further, the battery in the present disclosure may be used as a power source for moving bodies other than vehicles (for example, railways, ships, aircraft), or may be used as a power source for electrical products such as information processing devices.

Example

[0039] 《Fabrication of Electrode Stack》 〈Example 1〉 Fixing members were arranged on a pair of opposing side faces of the electrode stack as shown in Fig. 2(a) as follows. That is, an ultraviolet curable resin (Toagosei Co., Ltd., Aronix) was applied to a pair of opposing side faces of the electrode stack at intervals, and the resin was cured by irradiating it with ultraviolet light to arrange partial fixing members. The width of the partial fixing member was 100 mm, the width of the interval was 3 mm, and the thickness of the fixing member was 1 mm. The thickness of the fixing member and the width of the partial fixing member satisfied the following relational expression: Thickness of the fixing member ≤ (1 / Width of the partial fixing member) × 100. 〈Comparative Example 1〉 As shown in Fig. 4, fixing members were arranged in the same manner as in Example 1, except that an ultraviolet curable resin was applied to the side face of the electrode stack without leaving the above intervals so that the width of the fixing member was 250 mm and the thickness of the fixing member was 2.5 mm.

[0040] 《Evaluation》 The defective product (the one in which peeling of the fixing member occurred) rates were evaluated when 10 electrode stacks of Example 1 and Comparative Example 1 were each fabricated.

[0041] 《Results》 In the electrode stack of Example 1 in which the fixing member was composed of two or more partial fixing members arranged at intervals from each other, the defective product rate was 0%. In contrast, in the electrode stack of Comparative Example 1 in which one fixing member was arranged, the defective product rate was 40%.

Explanation of Reference Numerals

[0042] 10 Battery 11 Fixing member 11a Partial fixing member 11b Interval 12 Electrode stack 13 Laminate film 14 Current collector foil 15 Current collector terminal

Claims

1. An electrode laminate in which a fixing member containing a curable resin is disposed on at least one side surface, wherein the fixing member is composed of two or more partial fixing members that are spaced apart from each other. Electrode laminate.

2. The electrode laminate according to Claim 1, satisfying the following relational expression: Thickness of the fixing member ≤ (1 / width of the partial fixing member) × 100.

3. The electrode laminate according to Claim 1, wherein the thickness of the fixing member is 50 μm or more and 5 mm or less.

4. An electrode laminate according to any one of Claims 1 to 3, and A laminate film sealing the electrode laminate A battery having the same.

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