Non-aqueous electrolyte secondary battery

Abstract

To provide a nonaqueous electrolyte secondary battery which is capable of suppressing deterioration in cycle characteristics and includes a wide electrode body, and a method for manufacturing the same.SOLUTION: A nonaqueous electrolyte secondary battery includes an electrode body and an electrolytic solution. The electrode body is a wound type electrode body in which a positive electrode plate and a negative electrode plate are wound around a winding axis through a separator. The positive electrode plate and the negative electrode plate are bonded to the separator. The positive electrode plate includes a positive electrode active material layer, and the negative electrode plate includes a negative electrode active material layer. At least any one of the positive electrode active material layer and the negative electrode active material layer has a size in a winding axis direction of the electrode body of 150 mm or more. The electrolytic solution contains a solvent, an electrolyte, and an additive. The additive includes a compound LPFO represented by formula (1), and the content of the compound LPFO in the electrolytic solution is 0.15 mass% or more and 3.0 mass% or less.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a non-aqueous electrolyte secondary battery and a method for manufacturing the same.

Background Art

[0002] Japanese Patent Application Laid-Open No. 2010-198858 (Patent Document 1) discloses that by using a non-aqueous electrolyte solution containing 0.1% by weight or more and 5% by weight or less of compound PFO, capacity deterioration and output decrease due to charge and discharge cycles can be suppressed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In many cases, in a wide electrode body (for example, the dimension in the longitudinal direction of the active material layer is 15 cm or more), the electrode plate and the separator are adhered from the viewpoints of ease of can insertion, prevention of winding displacement, and prevention of springback. In a non-aqueous electrolyte secondary battery (hereinafter also referred to as a battery) including such an electrode body, the circulation of the electrolyte solution between the electrode plate and the separator may deteriorate when charge and discharge are repeated, and the cycle characteristics may deteriorate.

[0005] An object of the present disclosure is to provide a non-aqueous electrolyte secondary battery including a wide electrode plate and a method for manufacturing the same, in which a decrease in cycle characteristics is suppressed.

Means for Solving the Problems

[0006] The present invention provides the following non-aqueous electrolyte secondary battery and a method for manufacturing the same. [1] including an electrode body and an electrolyte solution, wherein the electrode body is a wound electrode body in which a positive electrode plate and a negative electrode plate are wound with a separator interposed therebetween, The positive electrode plate and the negative electrode plate are adhered to a separator, the positive electrode plate includes a positive electrode active material layer, the negative electrode plate includes a negative electrode active material layer, at least one of the positive electrode active material layer and the negative electrode active material layer has a dimension in the winding axis direction of the electrode body of 150 mm or more, the electrolytic solution contains a solvent, an electrolyte, and an additive, the additive is represented by the following formula (1):

Chemical formula

Chemical formula

Advantages of the Invention

[0007] According to the present disclosure, it is possible to provide a non-aqueous electrolyte secondary battery including a wide range of electrode bodies with suppressed deterioration of cycle characteristics and a method for manufacturing the same.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments. In all the following drawings, the scale is appropriately adjusted for easy understanding of each component, and the scale of each component shown in the drawings does not necessarily match the scale of the actual component.

[0010] In this specification, elements expressed in the singular form include the plural form as well, unless otherwise specified. For example, "particle" can mean not only "one particle" but also "an aggregate of particles (powder, powder, particle group)".

[0011] FIG. 1 is a schematic diagram showing an example of the configuration of a battery according to the present embodiment. The battery 100 can be used for any application. The battery 100 may be used as a main power source or a power assist power source, for example, in an electric vehicle or the like. A battery module or a battery pack may be formed by connecting a plurality of batteries 100. The battery 100 may have a rated capacity of, for example, 1 to 200 Ah.

[0012] The battery 100 includes an electrode body 50 and an electrolytic solution. As shown in FIG. 1, the battery 100 may further include an exterior body 90. The exterior body 90 houses the electrode body 50 and the electrolytic solution (not shown). The exterior body 90 is rectangular (flat rectangular parallelepiped). The exterior body 90 may be made of, for example, an aluminum (Al) alloy. The electrode body 50 may be housed in the exterior body 90 in a state where pressure is applied in the thickness direction (the D-axis direction in FIG. 1).

[0013] The exterior body 90 may include, for example, a sealing plate 91 and an exterior can 92. The sealing plate 91 closes the opening of the exterior can 92. For example, the sealing plate 91 and the exterior can 92 may be joined by laser processing or the like. Note that the exterior body 90 can have any form. The exterior body 90 may be, for example, a pouch shape or the like. That is, the exterior body 90 may be a pouch made of an Al laminate film or the like.

[0014] A positive electrode terminal 81 and a negative electrode terminal 82 are provided on the sealing plate 91. The sealing plate 91 may further be provided with an injection port (not shown), a gas discharge valve (not shown), and the like. The electrolytic solution can be injected into the interior of the exterior body 90 through the injection port. The injection port can be closed by, for example, a sealing plug or the like. The positive electrode current collector member 71 connects the positive electrode terminal 81 and the electrode body 50. The positive electrode current collector member 71 may be, for example, an Al plate or the like. The negative electrode current collector member 72 connects the negative electrode terminal 82 and the electrode body 50. The negative electrode current collector member 72 may be, for example, a copper (Cu) plate or the like.

[0015] The electrode body 50 can be a wound-type electrode body in which a positive electrode plate and a negative electrode plate are wound with a separator interposed therebetween. Each of the positive electrode plate, the negative electrode plate, and the separator may be, for example, a laminate having a strip-like planar shape. By winding the strip-like laminate in a spiral shape, a wound body can be formed. The wound body may be, for example, cylindrical. By compressing the cylindrical wound body in the radial direction, a flat electrode body 50 can be formed. The dimension of the electrode body 50 in the winding axis direction (hereinafter also referred to as the width direction) (in FIG. 1, the W-axis direction) may be, for example, 180 mm or more, or may be 180 mm or more and 300 mm or less.

[0016] FIG. 2 is a schematic diagram showing an example of the configuration of the electrode body in the present embodiment. The electrode body 50 in FIG. 2 is a wound-type electrode body having a winding axis R parallel to the W-axis direction. The electrode body 50 includes a laminate 40. The electrode body 50 may substantially consist of the laminate 40. The laminate 40 includes a positive electrode plate 10, a negative electrode plate 20, and a separator 30. At least a part of the separator 30 is interposed between the positive electrode plate 10 and the negative electrode plate 20. The separator 30 separates the positive electrode plate 10 and the negative electrode plate 20. The positive electrode plate 10 and the negative electrode plate 20 are each adhered to the separator 30. The separator 30 may have an adhesive layer described later on one or both sides. When the separator 30 has the adhesive layer described later, the positive electrode plate 10 and the negative electrode plate 20 can be adhered to the separator 30 via the adhesive layer, respectively. The laminate 40 may include a single separator 30 alone. The laminate 40 may include two separators 30. For example, the positive electrode plate 10 may be sandwiched between two separators 30. For example, the negative electrode plate 20 may be sandwiched between two separators 30. The laminate 40 may be formed, for example, by laminating a separator 30 (first separator), a negative electrode plate 20, a separator 30 (second separator), and a positive electrode plate 10 in this order.

[0017] FIG. 3 is a schematic cross-sectional view showing an example of the configuration of the electrode body in the present embodiment. FIG. 3 shows a cross-section orthogonal to the winding axis. The electrode body 50 includes a curved portion 51 and a flat portion 52. In the curved portion 51, the laminate 40 is curved. In the curved portion 51, the laminate 40 may form an arc. In the flat portion 52, the laminate 40 is flat. The flat portion 52 is sandwiched between two curved portions 51. The flat portion 52 connects the two curved portions 51. The thickness of the laminate 40 indicates the total thickness of the positive electrode plate 10, the negative electrode plate 20, and the separator 30 included in the laminate 40. The laminate 40 may have a thickness of, for example, 100 to 200 μm, or may have a thickness of 1 to 100 mm.

[0018] In the electrode body 50, the positive electrode plate 10 can have an arbitrary number of laminations. The number of laminations of the positive electrode plate 10 indicates the number of times a straight line crossing the electrode body 50 in the lamination direction intersects the positive electrode plate 10. The lamination direction indicates the direction in which the positive electrode plate 10, the negative electrode plate 20, and the separator 30 are laminated in the electrode body 50. In the wound-type electrode body 50, the lamination direction is parallel to the thickness direction of the positive electrode plate 10, the negative electrode plate 20, and the separator 30 in the flat portion 52 (the D-axis direction in FIG. 3).

[0019] As shown in FIG. 4, the electrode body 50 is manufactured by laminating the positive electrode plate 10 and the negative electrode plate 20 with the separator 30 interposed therebetween so that the aluminum foil of the positive electrode plate and the copper foil of the negative electrode plate are exposed at both ends, respectively, to form a laminate, and then winding the laminate with one end as the winding axis R to manufacture the electrode body 50.

[0020] The positive electrode plate 10 may have, for example, 2 to 100 laminations. The negative electrode plate 20 may have, for example, 2 to 100 laminations. The separator 30 may have, for example, 4 to 200 laminations. The number of laminations of the negative electrode plate 20 and the separator 30 can also be counted in the same manner as the number of laminations of the positive electrode plate 10.

[0021] The positive electrode plate 10 includes a positive electrode active material layer. In FIG. 1, the dimension of the positive electrode active material layer in the direction parallel to the winding axis direction (W-axis direction) of the electrode body 50 is 150 mm or more, and may be, for example, 180 mm or more, or 200 mm or more, or 220 mm or more, and may be 300 mm or less. The positive electrode active material layer will be described later.

[0022] The negative electrode plate 20 includes a negative electrode active material layer. In FIG. 1, the dimension of the negative electrode active material layer in the direction parallel to the winding axis direction (W-axis direction) of the electrode body 50 is 150 mm or more, and may be, for example, 180 mm or more, or 200 mm or more, or 220 mm or more, and may be 300 mm or less. The negative electrode active material layer will be described later.

[0023] The positive electrode plate 10 includes a positive electrode core material 11 and a positive electrode active material layer 12 (see FIG. 2). The positive electrode active material layer 12 may be disposed on the surface of the positive electrode core material 11. The positive electrode active material layer 12 may be disposed on only one side of the positive electrode core material 11. The positive electrode active material layer 12 may be disposed on both the front and back surfaces of the positive electrode core material 11. The positive electrode core material 11 is a conductive sheet. The positive electrode core material 11 may include, for example, pure Al foil, Al alloy foil, etc. The positive electrode core material 11 may have a thickness of, for example, 10 to 30 μm. In the width direction (W-axis direction in FIG. 2) of the electrode body 50, the positive electrode core material 11 may be exposed at one end. The positive electrode current collector member 71 may be joined to the exposed portion of the positive electrode core material 11 (see FIG. 1). The thickness of the positive electrode plate 10 may be, for example, 20 to 290 μm, may be 50 to 250 μm, and may be 100 to 200 μm. The dimension of the positive electrode plate 10 in the longitudinal direction may be, for example, 0.5 to 5 m, and may be 1 to 3 m.

[0024] The thickness of the positive electrode active material layer 12 indicates the total thickness of the positive electrode active material layers 12 included in the laminate 40. For example, when the positive electrode active material layers 12 are formed on both sides of the positive electrode plate 10, the thickness of the positive electrode active material layer 12 indicates the total thickness of the positive electrode active material layers 12 on both sides (two sides). The positive electrode active material layer 12 may have a thickness of, for example, 10 to 260 μm, or may have a thickness of 20 to 60 μm, or may have a thickness of 30 to 50 μm. Note that the thickness of the positive electrode active material layer 12 on one side (one side) may be, for example, 10 to 30 μm, or may be 15 to 25 μm.

[0025] The positive electrode active material layer 12 can contain a lithium transition metal composite oxide. The lithium transition metal composite oxide is, for example, LiCoO 2 , LiNiO 2 , LiMnO 2 , LiMn 2 O 4 , Li(NiCoMn)O 2 , Li(NiCoAl)O 2 , and at least one selected from the group consisting of LiFePO 4 . For example, in a composition formula such as "Li(NiCoMn)O 2 ", the sum of the composition ratios in the parentheses is 1. That is, the relationship of "C Ni + C Co + C Mn = 1" is satisfied. For example, "C Ni " indicates the composition ratio of Ni. As long as the sum of the composition ratios is 1, the composition ratios of the respective components are arbitrary. The positive electrode active material layer 12 can contain positive electrode active material particles. The positive electrode active material particles can contain any components. The positive electrode active material particles can contain the above-described lithium transition metal composite oxide.

[0026] The positive electrode active material layer 12 may further contain, for example, a conductive material, a binder, etc. in addition to the positive electrode active material particles. For example, the positive electrode active material layer 12 may substantially consist of a conductive material with a mass fraction of 0.1 to 10%, a binder with a mass fraction of 0.1 to 10%, and the remaining positive electrode active material particles. The conductive material may contain, for example, a carbon material, etc. The binder can contain any components. The binder may contain, for example, polyvinylidene fluoride (PVdF), etc. The packing density (after compression) of the positive electrode active material layer 12 is, for example, 3.0 g / cm 3 or more and 4.0 g / cm 3 or less.

[0027] The negative electrode plate 20 includes a negative electrode core material 21 and a negative electrode active material layer 22 (see FIG. 2). The negative electrode active material layer 22 may be disposed on the surface of the negative electrode core material 21. The negative electrode active material layer 22 may be disposed on only one side of the negative electrode core material 21. The negative electrode active material layer 22 may be disposed on both the front and back surfaces of the negative electrode core material 21. The negative electrode core material 21 is a conductive sheet. The negative electrode core material 21 may contain, for example, pure Cu foil, Cu alloy foil, etc. The negative electrode core material 21 may have a thickness of, for example, 5 to 30 μm. In the width direction (W-axis direction in FIG. 2) of the negative electrode plate 20, the negative electrode core material 21 may be exposed at one end. A negative electrode current collector member 72 can be joined to the exposed portion of the negative electrode core material 21 (see FIG. 1). The thickness of the negative electrode plate 20 may be, for example, 20 to 290 μm, may be 50 to 250 μm, and may be 100 to 200 μm. The longitudinal dimension of the negative electrode plate 20 may be, for example, 0.5 to 5 m, and may be 1 to 3 m.

[0028] The thickness of the negative electrode active material layer 22 indicates the total thickness of the negative electrode active material layers 22 included in the laminate 40. For example, when the negative electrode active material layers 22 are formed on both surfaces of the negative electrode plate 20, the thickness of the negative electrode active material layer 22 indicates the total thickness of the negative electrode active material layers 22 on both surfaces (two surfaces). The negative electrode active material layer 22 may have a thickness of, for example, 10 to 260 μm, may have a thickness of 40 to 80 μm, or may have a thickness of 50 to 70 μm. Note that the thickness of the negative electrode active material layer 22 on one surface (one surface) may be, for example, 20 to 40 μm or 25 to 35 μm. The packing density (after compression) of the negative electrode active material layer 22 is, for example, 1.3 g / cm 3 or more and 1.8 g / cm 3 or less.

[0029] The negative electrode active material layer 22 may contain, for example, at least one selected from the group consisting of graphite, silicon, silicon oxide, tin, tin oxide, and Li 4 Ti 5 O 12 as the negative electrode active material. The negative electrode active material layer 22 can contain negative electrode active material particles. The negative electrode active material particles can contain the above-described negative electrode active material. The negative electrode active material layer 22 may consist essentially of negative electrode active material particles. The negative electrode active material particles may be, for example, composite particles. The negative electrode active material particles may contain, for example, a base material particle and a film. The film can cover the surface of the base material particle. The base material particle may contain, for example, graphite or the like. The film may contain, for example, amorphous carbon or the like.

[0030] In addition to the negative electrode active material particles, the negative electrode active material layer 22 may further contain a conductive material, a binder, and the like. For example, the negative electrode active material layer 22 may consist essentially of 0 to 10% of a conductive material, 0.1 to 10% of a binder, and the balance of negative electrode active material particles by mass fraction. The conductive material can contain any component. The conductive material may contain, for example, a carbon material or the like. The binder can contain any component. The binder may contain, for example, at least one selected from the group consisting of carboxymethyl cellulose (CMC) and styrene-butadiene rubber (SBR).

[0031] Separator 30 includes a resin film. Separator 30 may consist substantially of a resin film. The resin film may, for example, consist substantially of a polyolefin-based material. The polyolefin-based material may include, for example, at least one selected from the group consisting of polyethylene (PE) and polypropylene (PP). The resin film may have a thickness of, for example, 10 to 50 μm, may have a thickness of 10 to 30 μm, or may have a thickness of 10 to 20 μm. The resin film may be porous. The air permeability of the separator may be, for example, 100 to 300 sec / cc.

[0032] Separator 30 may have an adhesive layer on one or both sides. Separator 30 can have a resin film and an adhesive layer disposed on at least one side of the resin film. The adhesive layer can have the function of joining the positive electrode plate 10 and the separator 30, and joining the negative electrode plate 20 and the separator 30. From the viewpoints of ease of can insertion, prevention of slippage, and prevention of springback, it is preferable that adhesive layers are disposed on both sides of separator 30. The adhesive layer can include, for example, an acrylic resin and a fluorine-based polymer. The fluorine polymer includes, for example, PVdF and the like. The adhesive layer can further include a filler. The filler includes, for example, ceramic particles and the like. When the adhesive layer includes a filler, the content of the filler may be, for example, 70% by mass or more. The thickness of the adhesive layer may be, for example, 1 to 10 μm, or may be 1 to 5 μm. The thickness of the adhesive layer indicates the total thickness of the adhesive layers included in separator 30. For example, when separator 30 has adhesive layers on both sides, it indicates the total thickness of the adhesive layers on both sides (two). The basis weight of the adhesive layer on separator 30 (when including two adhesive layers, the total basis weight) may be, for example, 6.0 to 10.0 g / m 2 It may be.

[0033] The separator 30 may have a heat-resistant layer on the side facing the positive electrode plate. When the separator 30 has an adhesive layer and a heat-resistant layer, the heat-resistant layer and the adhesive layer can be arranged in this order from the resin film side. The heat-resistant layer can contain, for example, an acrylic resin and a filler. The filler can contain, for example, ceramic particles and the like. When the heat-resistant layer contains a filler, the content of the filler may be, for example, 90% by mass or more. The thickness of the heat-resistant layer may be, for example, 1 to 10 μm, and may be 1 to 5 μm.

[0034] The electrolytic solution is a liquid electrolyte. The electrolytic solution contains a solvent, an electrolyte, and an additive. The solvent is aprotic. The solvent can contain any component. The solvent can contain at least one selected from the group consisting of carbonate solvents, 1,2-dimethoxyethane (DME), methyl formate (MF), methyl acetate (MA), methyl propionate (MP), and γ-butyrolactone (GBL). The solvent preferably contains a carbonate solvent. Examples of the carbonate solvent include ethylene carbonate (EC), propylene carbonate (PC), butylene carbonate (BC), dimethyl carbonate (DMC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC).

[0035] The electrolyte is dissolved in the solvent. The electrolyte contains, for example, a lithium salt (hereinafter also referred to as Li salt). The Li salt may contain at least one selected from the group consisting of, for example, LiPF 6 , LiBF 4 , and LiN(FSO 2 ) 2 . The Li salt may have a molar concentration of, for example, 0.2 to 2.0 M (mol / L).

[0036] The additive is represented by the following formula (1):

Chemical formula

[0037] The additive may further contain at least one selected from the group consisting of vinylene carbonate (VC) and vinyl ethylene carbonate (VEC) as other compounds other than the compound LPFO. When the additive contains other compounds, the content of the other compounds in the electrolytic solution can include, for example, 0.01% by mass or more and 5% by mass or less.

[0038] The battery of the present disclosure can have a capacity retention rate exceeding 92% in the evaluation of cycle characteristics. The evaluation of cycle characteristics is performed according to the method described in the column of Examples below.

[0039] The method for manufacturing a battery can include, for example, a housing step of housing an electrode body in an exterior body, and a liquid injection step of injecting an electrolytic solution. In the housing step, the aluminum foil of the positive electrode current collector member is welded to the external current collector aluminum plate of the electrode body, and the copper foil of the negative electrode current collector member is welded to the external current collector copper plate of the electrode body, and it can be inserted into the exterior body of the aluminum laminate film. In the liquid injection step, the above-described electrolytic solution can be injected. After the liquid injection, the battery can be obtained by can-sealing welding.

Example

[0040] Hereinafter, the present invention will be described in more detail with reference to examples. In the examples, “%” and “parts” are mass % and parts by mass, respectively, unless otherwise specified.

[0041] [Separator] The following separators A and B were prepared. The air permeability of both was 200 sec / cc. Separator A: An adhesive layer (thickness on one side: 2 μm, total thickness on both sides: 4 μm, basis weight: 4.0 g / m 2 ) made of an acrylic resin (PVdF) containing 75% by mass of ceramic particles is provided on both sides of a base material (thickness: 12 μm) made of a polyethylene resin. A separator with an adhesive layer. Separator B: A heat-resistant layer (thickness: 4 μm, basis weight: 8.0 g / m 2 ) made of an acrylic binder containing 90% by mass of ceramic particles is provided on one side (positive electrode side) of a base material (thickness: 12 μm) made of a polyethylene resin. A separator.

[0042] [Positive electrode plate] A positive electrode plate provided with a positive electrode active material layer containing a lithium transition metal composite oxide as a positive electrode active material, PVdF as a positive electrode binder, and a carbon material as a conductive material was prepared on both sides of an aluminum foil. The thickness of the positive electrode plate was 0.15 mm, the dimension in the longitudinal direction was 2.5 m, the packing density of the positive electrode active material layer was 3.5 g / cc, and the width of the positive electrode active material layer was 220 mm.

[0043] [Negative electrode plate] A negative electrode plate was prepared with a negative electrode active material layer containing graphite as a negative electrode active material, SBR and CMC as negative electrode binders, and a carbon material as a conductive material on both sides of the copper foil. The thickness of the negative electrode plate was 0.18 mm, the dimension in the longitudinal direction was 2.75 m, the filling density of the negative electrode active material layer was 1.5 g / cc, and the width of the negative electrode active material layer was 224 mm.

[0044] [Electrolyte] A solvent containing EC and EMC (volume ratio of EC:EMC = 1:3), an electrolyte (1M LiPF 6 ), a first additive (VC 0.8 mass%), and LPFO with the content shown in Table 1 as a second additive were used to prepare electrolyte A. Also, electrolyte B and electrolyte C containing LiPF 2 O 2 and LiBOB respectively were prepared. Furthermore, a solvent containing EC and EMC (volume ratio of EC:EMC = 1:3), an electrolyte (1M LiPF 6 ), a first additive (VC 0.8 mass%), and an electrolyte D without a second additive were prepared.

[0045] [Evaluation of cycle characteristics] Under a 25°C environment, charging was performed at a current value of 1C to 4.2V, and discharging from 4.2V to 3V at a current value of 1C was defined as one cycle, and the charge and discharge were repeated. The retention rate of the discharge capacity at the 500th cycle with respect to the discharge capacity at the first cycle was defined as the capacity retention rate. The capacity retention rate was calculated according to the following formula: Capacity retention rate = (Discharge capacity at the 500th cycle / Discharge capacity at the first cycle) × 100 (%) and was calculated according to this formula. The evaluation criteria are shown below. ○: Capacity retention rate exceeding 91%. △: Capacity retention rate of 87 - 91%. ×: Capacity retention rate less than 87%.

[0046] [Example 1] The positive electrode plate and the negative electrode plate were laminated via a separator A such that the aluminum foil of the positive electrode plate and the copper foil of the negative electrode plate were exposed at both ends respectively to produce a laminate, and the laminate was wound using one end of the laminate as a winding shaft to create a wound electrode body (width: 300 mm). After pressing this wound body at 150 kN, the aluminum foil of the positive electrode plate of the electrode body was welded to the aluminum plate of the positive current collector member, and the copper foil of the negative electrode plate of the electrode body was welded to the copper plate of the negative current collector member. It was inserted into an Al exterior can of a predetermined size, 150 cc of electrolyte A was injected, and then can sealing welding was performed to produce a battery cell. The evaluation results of the cycle characteristics are shown in Table 1.

[0047] <Comparative Examples 1 to 7> A battery cell was produced in the same manner as in Example 1 except that the electrolyte, the second additive, and the separator shown in Table 1 were used. When separator B was used, the positive electrode plate, the negative electrode plate, and the separator were not adhered. The evaluation results of the cycle characteristics are shown in Table 1.

[0048]

Table 1

[0049] <Reference Examples 1 to 5> Battery cells of Reference Examples 1 to 5 were produced in the same manner except that the widths of the positive electrode active material layer and the negative electrode active material layer were 110 mm and 112 mm respectively in Example 1, Comparative Example 3, Comparative Example 4, Comparative Example 6, and Comparative Example 8. The evaluation results of the cycle characteristics are shown in Table 2.

[0050]

Table 2

[0051] In Example 1 according to the present disclosure, excellent cycle characteristics were obtained compared to Comparative Examples 1 to 7 not according to the present disclosure. Although all of Reference Examples 1 to 5 had good cycle characteristics, this is presumably because when the electrode body has a narrow active material layer width, the liquid surrounding is improved. It can be understood that according to the present disclosure, a non-aqueous electrolyte secondary battery including a wide electrode body with suppressed deterioration of cycle characteristics is provided.

Description of Symbols

[0052] 10 Positive electrode plate, 11 Positive electrode core material, 12 Positive electrode active material layer, 20 Negative electrode plate, 21 Negative electrode core material, 22 Negative electrode active material layer, 30 Separator, 40 Stacked body, 50 Electrode body, 51 Curved portion, 52 Flat portion, 71 Positive electrode current collector member, 72 Negative electrode current collector member, 81 Positive electrode terminal, 82 Negative electrode terminal, 90 Exterior body, 91 Sealing plate, 92 Exterior can, 100 Battery, W Width direction, R Winding axis.

Claims

1. comprising an electrode body and an electrolytic solution, wherein the electrode body is a wound electrode body in which a positive electrode plate and a negative electrode plate are wound with a separator interposed therebetween, the positive electrode plate and the negative electrode plate are adhered to the separator, the positive electrode plate includes a positive electrode active material layer, the negative electrode plate includes a negative electrode active material layer, at least one of the positive electrode active material layer and the negative electrode active material layer has a dimension in the winding axis direction of the electrode body of 150 mm or more, the electrolytic solution contains a solvent, an electrolyte, and an additive, the additive includes a compound LPFO represented by the following formula (1): 【Chemical 1】 A non-aqueous electrolyte secondary battery, including the compound LPFO, and the content of the compound LPFO in the electrolytic solution is 0.15% by mass or more and 3.0% by mass or less.

2. The non-aqueous electrolyte secondary battery according to claim 1, wherein the separator has a resin film and an adhesive layer disposed on at least one side of the resin film.

3. The non-aqueous electrolyte secondary battery according to claim 1, further including an outer package, and the electrode body is housed in the outer package in a state where pressure is applied in the thickness direction.

4. The non-aqueous electrolyte secondary battery according to claim 1, wherein the dimension of the electrode body in the winding axis direction is 180 mm or more.

5. including a housing step of housing an electrode body in an outer package and a liquid injection step of injecting an electrolytic solution, wherein the electrode body is a wound electrode body in which a positive electrode plate and a negative electrode plate are wound with a separator interposed therebetween, the positive electrode plate and the negative electrode plate are adhered to the separator, the positive electrode plate includes a positive electrode active material layer, the negative electrode plate includes a negative electrode active material layer, at least one of the positive electrode active material layer and the negative electrode active material layer has a dimension in the winding axis direction of the electrode body of 150 mm or more, the electrolytic solution contains a solvent, an electrolyte, and an additive, the additive includes a compound LPFO represented by the following formula (1): 【Chemical Formula 2】 A method for manufacturing a non-aqueous electrolyte secondary battery, including the compound LPFO, and the content of the compound LPFO in the electrolytic solution is 0.15% by mass or more and 3.0% by mass or less.

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