JP5007507B2 - Non-aqueous electrolyte composition for secondary battery and non-aqueous electrolyte secondary battery - Google Patents

Description

The present invention relates to a nonaqueous electrolyte composition and nonaqueous electrolyte secondary battery for a secondary battery, more specifically, predetermined with carbonate, containing a sulfonyl compound consisting of sulfo down with a cyclic sulfonic acid ester or multiple bonds The present invention relates to a non-aqueous electrolyte composition for a secondary battery and a lithium ion non-aqueous electrolyte secondary battery using such a non-aqueous electrolyte composition for a secondary battery.

  In recent years, many portable electronic devices such as a camera-integrated VTR (video tape recorder), a digital camera, a mobile phone, a personal digital assistant, and a notebook computer have appeared, and their size and weight have been reduced. As a portable power source for these electronic devices, research and development for improving the energy density of batteries, particularly secondary batteries, are being actively promoted.

  Among them, a lithium ion secondary battery using carbon as a negative electrode active material, a lithium-transition metal composite oxide as a positive electrode active material, and a carbonate ester mixture as an electrolyte is a lead battery or a conventional non-aqueous electrolyte secondary battery. Since a large energy density can be obtained as compared with a nickel cadmium battery, it has been widely put into practical use (for example, see Patent Document 1).

In particular, a laminated battery using an aluminum laminated film for an exterior has a high energy density because it is lightweight (see, for example, Patent Document 2).
In such a laminated battery, since the deformation of the battery can be suppressed by using a polymer swollen with an electrolytic solution, a laminated polymer battery is also widely used (for example, see Patent Document 3).
JP-A-4-332479 Japanese Patent No. 3482591 JP 2005-166448 A

However, with the recent increase in capacity of batteries, the density of the electrode active material disposed on the electrodes has increased and the gaps have become smaller, making it difficult to sufficiently impregnate the electrodes with the electrolyte. It has become to.
When the electrolyte is not sufficiently impregnated in this way, metallic lithium is deposited on the carbon surface of the negative electrode, and the battery exterior may swell and deform when stored at high temperatures. there were.

The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide a non-aqueous battery for a secondary battery that can prevent the battery casing from being swollen and deformed during high-temperature storage. An object of the present invention is to provide an electrolyte composition and a nonaqueous electrolyte secondary battery using such a nonaqueous electrolyte composition for a secondary battery.

  As a result of intensive studies to achieve the above object, the present inventors use at least one of a cyclic sulfonate ester (sultone) and a sulfone having a multiple bond (unsaturated sulfone) together with a predetermined chain carbonate ester. As a result, the inventors have found that the above object can be solved, and have completed the present invention.

That is, the secondary battery for non-aqueous electrolyte composition of the present invention, an electrolyte salt, a nonaqueous solvent, a chain ester carbonate having at least a hydrocarbon group having a carbon number of 13 to 20, a cyclic sulfonic acid ester or A sulfonyl compound comprising a sulfone having a multiple bond, and the content of the chain carbonate ester is 0.1% by mass or more and 2% by mass or less with respect to the total mass of the nonaqueous electrolyte composition for a secondary battery. The content of the sulfonyl compound is from 0.1% by mass to 0.5% by mass with respect to the total mass of the nonaqueous electrolyte composition for secondary batteries .

Moreover, the nonaqueous electrolyte secondary battery of the present invention contains a positive electrode and a negative electrode using a material capable of inserting and extracting lithium ions as a positive electrode active material or a negative electrode active material, a nonaqueous electrolyte composition, a separator, and these. a non-aqueous electrolyte secondary battery comprising a package member, a non-aqueous electrolyte composition, an electrolyte salt, a nonaqueous solvent, a chain carbonate having a hydrocarbon group having at least carbon atoms 13 to 20, the annular sulfonic acid ester or contains a sulfonyl compound consisting of sulfonic having a multiple bond, the content of the chain carbonate is, with respect to the total mass of the nonaqueous electrolyte composition 0.1 wt% or more 2% The content of the sulfonyl compound is 0.1% by mass or more and 0.5% by mass or less with respect to the total mass of the nonaqueous electrolyte composition .

According to the present invention, since the predetermined chain carbonate ester and the cyclic sulfonate ester or the sulfone having multiple bonds are used , the non- secondary battery non- rechargeable battery can be prevented from being swelled during storage at high temperatures. A water electrolyte composition and a nonaqueous electrolyte secondary battery using the same can be provided.

  Hereinafter, the nonaqueous electrolyte composition of the present invention will be described in detail. In the present specification, “%” represents mass percentage unless otherwise specified.

As described above, the non-aqueous electrolyte composition of the present invention includes an electrolyte salt, a non-aqueous solvent, a chain carbonate having a hydrocarbon group or a halogenated hydrocarbon group having 13 to 20 carbon atoms, and a cyclic sulfone. It contains at least one of an acid ester (sultone) and a sulfone having a multiple bond (unsaturated sulfone), and is suitably used for a lithium ion non-aqueous electrolyte secondary battery.
Such a chain carbonate ester is excellent in impregnation or permeability to a positive electrode active material layer, a negative electrode active material layer, and a separator, which will be described later, can suppress deterioration of battery performance, and improve the discharge capacity maintenance rate during repeated charge and discharge. In addition, the electrolyte can be sufficiently permeated into the electrode to prevent the deposition of metallic lithium on the carbon surface, thereby suppressing the swelling of the battery exterior, typically at a high temperature of 60 to 90 ° C.

  Here, as the chain carbonic acid ester having a hydrocarbon group or a halogenated hydrocarbon group having 13 to 20 carbon atoms, the following chemical formula (1)

[R1 in the formula _{C n H 2n + 1-m} X m (X is fluorine (F), chlorine (Cl), bromine (Br) or iodine (I), n represents an integer of 13 to 20, m is 0 ≦ m ≦ 2n is satisfied.), R2 is C _n H _{2n + 1−m} X _m (X is F, Cl, Br or I, n is an integer of 1 to 20, and m is 0 ≦ m ≦ 2n) ). The compound represented by this can be mentioned.

In R1 of the formula (1), as described above, the number of carbons is required to be 13 to 20, but 13 to 14 is more preferable. When the number of carbon atoms in R1 is less than 13, the permeability is insufficient. On the other hand, when it exceeds 20, the solubility in the electrolytic solution decreases.
Similarly, the number of carbon atoms in R2 is required to be 1-20, but is preferably 1-14, more preferably 5-14. When the number of carbon atoms in R2 exceeds 20, the solubility in the electrolytic solution decreases.

In addition, it is preferable from a viewpoint of manufacture that the carbon number of R1 and R2 is mutually the same.
The halogen element is preferably fluorine, and the number of halogen elements is preferably 1 to (2n-1), more preferably 1 to 6. When the number of halogen elements exceeds 6, the solubility in the electrolytic solution may decrease.

Specifically, as the chain carbonate represented by the formula (1), ditridecyl carbonate [C ₁₃ H ₂₇ O) ₂ CO (2)] represented by the following chemical formulas 2 to 4, respectively, Tetradecyl carbonate [(C ₁₄ H ₂₉ O) ₂ CO (3)] and dieicosyl carbonate [(C ₂₀ H ₄₁ O) ₂ CO) (4)] can be preferably used. Needless to say, it is not limited to compounds.
That is, in the present invention, any chain carbonate ester having the structure of the formula (1) can be applied, including structural isomers in which the hydrocarbon group of the above compound is branched from a straight chain.

In the nonaqueous electrolyte composition of the present invention, the content of the chain carbonate is preferably 0.05 to 5%, more preferably 0.1 to 2%.
That is, if the content of the chain carbonate is less than 0.05%, the effect is not sufficient, and if it exceeds 5%, the capacity during large current discharge may decrease.

In the non-aqueous electrolyte composition of the present invention, it is necessary to contain at least one of a cyclic sulfonate ester (sultone) and a sulfone having a multiple bond (unsaturated sulfone) in addition to the chain carbonate ester.
Since these sultone and unsaturated sulfone are considered to have a function of forming a protective film, swelling of the battery using the nonaqueous electrolyte composition during high temperature storage can be effectively suppressed.

  Here, the cyclic sulfonic acid ester, ie, sultone, has the following chemical formula (5)

[R1 is _C n _{H 2n} in the formula (n denotes. A natural number) indicates a] include a compound represented by.

  In R1 of the formula (5), the number of carbon atoms is preferably 2 to 5. However, if the number of carbon atoms is less than 2, the carbon is unstable. On the other hand, if it exceeds 5, the film tends to be too stable to form a film. is there.

  Specific examples of the cyclic sulfonic acid ester represented by the formula (5) include 1,3-propane sultone (6), 1,3-butane sultone represented by the following chemical formulas 6 to 9, respectively. 7), 1,3-propene sultone (8), and toluene sultone (9) can be preferably used, but it is needless to say that the compounds are not limited to these compounds. Any sultone having the structure of formula 5) is applicable.

  On the other hand, examples of the sulfone having multiple bonds, ie, unsaturated sulfone, include the following chemical formula (10)

[R2 in the _{formula, C n H 2n + 1 (} n is an alkyl group is an integer from 1 to _{4), C n H 2n-1} ( alkylene n is an integer from 1 to 4), or _C n _{H 2n -7} (showing an aryl group where n is an integer of 6 to 8)].

(10) In the case of R2 in the formula, in the case of an alkyl group represented by C _n H _{2n + 1} or an alkylene group represented by C _n H _2n-1 , when the number of carbons exceeds 4, the capacity at the time of large current discharge decreases. Tend.
Further, in the case of the aryl group represented by C _n H _2n-7 , if the number of carbon atoms is less than 6, it is unstable, and if it exceeds 8, the capacity at the time of large current discharge tends to decrease.

  Specific examples of the unsaturated sulfone represented by the formula (10) include divinyl sulfone (11), methyl vinyl sulfone (12), and phenyl vinyl sulfone represented by the following chemical formulas 11 to 13, respectively. Although (13) can be preferably used, it is needless to say that the compound is not limited to these compounds, and is applicable to unsaturated sulfones having the structure of the formula (10), including alkyl-substituted products of the above compounds.

In the nonaqueous electrolyte composition of the present invention, the content of the sultone and unsaturated sulfone is preferably in the range of about 0.05 to 2%.
That is, when the content of each of these compounds is less than 0.05%, the effect is small, and when each content exceeds 2%, the capacity during large current discharge may decrease.

As described above, the nonaqueous electrolyte composition of the present invention comprises at least one of the sultone and unsaturated sulfone as an essential component together with the chain carbonate ester, but other compounds can be added in addition to this. is there.
Specifically, it is possible to combine other carbonic acid esters having a carbon-carbon double bond, such as vinylene carbonate and vinylene ethylene carbonate, thereby improving the discharge capacity maintenance rate during repeated charge and discharge. Can do.

  The content of the other carbonic acid ester having such a carbon-carbon double bond is preferably 0.05 to 5%. If it is less than 0.05%, the effect is not sufficient. On the other hand, if it exceeds 5%, the capacity during large current discharge may decrease.

Furthermore, a predetermined polymer compound is added, and the polymer compound is swollen with the non-aqueous electrolyte composition of the present invention so that the polymer compound is impregnated or held in the polymer compound. Can do.
The swelling, gelation or non-fluidization of the polymer compound can effectively suppress the occurrence of leakage of the nonaqueous electrolyte composition in the obtained battery. In addition, the chain carbonic acid ester represented by the above formula (1) is presumed to have good impregnation properties with respect to such a polymer compound, and the discharge capacity maintenance rate at the time of repeated charge / discharge of the obtained battery is also improved. It seems to do.

  Examples of such a polymer compound include polyvinyl formal (14), polyacrylic acid ester (15), polyvinylidene fluoride (16) represented by the following chemical formulas 14 to 16.

However, R in the formula (15) represents C _n H _2n-1 O _m (n represents an integer of 1 to 8, m represents an integer of 0 to 4), N represents a degree of polymerization, preferably N = 100 to 10,000. At this time, if N is less than 100, gelation is difficult, and if it exceeds 10,000, fluidity tends to decrease.

  In addition, it is preferable that content of the above-mentioned polymer compound shall be 0.1 to 5%. If it is less than 0.1%, gelation becomes difficult, and if it exceeds 5%, fluidity may be reduced.

Examples of the non-aqueous solvent used in the non-aqueous electrolyte composition of the present invention include various high dielectric constant solvents and low viscosity solvents.
As the high dielectric constant solvent, ethylene carbonate, propylene carbonate, and the like can be suitably used, but are not limited thereto, butylene carbonate, vinylene carbonate, 4-fluoro-1,3-dioxolan-2-one Cyclic carbonates such as (fluoroethylene carbonate), 4-chloro-1,3-dioxolan-2-one (chloroethylene carbonate), and trifluoromethylethylene carbonate can be used.

  Further, as a high dielectric constant solvent, instead of or in combination with a cyclic carbonate, a lactone such as γ-butyrolactone and γ-valerolactone, a lactam such as N-methylpyrrolidone, and a cyclic carbamic acid such as N-methyloxazolidinone Sulfone compounds such as esters and tetramethylene sulfone can also be used.

  On the other hand, diethyl carbonate can be preferably used as the low-viscosity solvent, but besides this, chain carbonates such as dimethyl carbonate, ethyl methyl carbonate and methyl propyl carbonate, methyl acetate, ethyl acetate, propionic acid Chain carboxylic acid esters such as methyl, ethyl propionate, methyl butyrate, methyl isobutyrate, methyl trimethylacetate and ethyl trimethylacetate, chain amides such as N, N-dimethylacetamide, methyl N, N-diethylcarbamate and N , N-diethylcarbamate ethyl ester and the like, and 1,2-dimethoxyethane, tetrahydrofuran, tetrahydropyran, and ether such as 1,3-dioxolane can be used.

In the non-aqueous electrolyte composition of the present invention, the high dielectric constant solvent and the low viscosity solvent described above can be used alone or in combination of two or more.
Moreover, it is preferable that content of the above-mentioned non-aqueous solvent shall be 70 to 90%. If it is less than 70%, the viscosity increases, and if it exceeds 90%, sufficient electrical conductivity may not be obtained.

The electrolyte salt used in the non-aqueous electrolyte composition of the present invention may be any salt that dissolves or disperses in the above-described non-aqueous solvent to generate ions, and lithium hexafluorophosphate (LiPF ₆ ) is preferably used. Needless to say, the present invention is not limited to this.
That is, lithium tetrafluoroborate (LiBF _4), lithium hexafluoroarsenate (LiAsF _6), lithium hexafluoro antimonate (LiSbF _6), lithium perchlorate (LiClO _4), four lithium aluminum chloride acid ( Inorganic lithium salts such as LiAlCl ₄ ), lithium trifluoromethanesulfonate (LiCF ₃ SO ₃ ), lithium bis (trifluoromethanesulfone) imide (LiN (CF ₃ SO ₂ ) ₂ ), lithium bis (pentafluoromethanesulfone) methide (LiN (C ₂ F ₅ SO ₂ ) ₂ ) and lithium salts of perfluoroalkanesulfonic acid derivatives such as lithium tris (trifluoromethanesulfone) methide (LiC (CF ₃ SO ₂ ) ₃ ) can also be used. These can be used alone or in combination of two or more. It is also possible to use it.

  In addition, it is preferable that content of such electrolyte salt shall be 10 to 30%. If it is less than 10%, sufficient conductivity cannot be obtained, and if it exceeds 30%, the viscosity may increase.

Next, the nonaqueous electrolyte secondary battery of the present invention will be described in detail.
FIG. 1 is an exploded perspective view showing an example of a laminated battery as an embodiment of the nonaqueous electrolyte secondary battery of the present invention.
In the figure, the secondary battery is configured by enclosing a battery element 20 to which a positive electrode terminal 11 and a negative electrode terminal 12 are attached in a film-like exterior member 30. The positive electrode terminal 11 and the negative electrode terminal 12 are led out, for example, in the same direction from the inside of the exterior member 30 to the outside. The positive electrode terminal 11 and the negative electrode terminal 12 are each made of a metal material such as aluminum (Al), copper (Cu), nickel (Ni), or stainless steel.

The exterior member 30 is configured by a rectangular laminate film in which, for example, a nylon film, an aluminum foil, and a polyethylene film are bonded together in this order. The exterior member 30 is arrange | positioned so that the polyethylene film side and the battery element 20 may oppose, for example, and each outer edge part is mutually joined by melt | fusion or the adhesive agent.
An adhesion film 31 is inserted between the exterior member 30 and the positive electrode terminal 11 and the negative electrode terminal 12 to prevent intrusion of outside air. The adhesion film 31 is made of a material having adhesion to the positive electrode terminal 11 and the negative electrode terminal 12. For example, when the positive electrode terminal 11 and the negative electrode terminal 12 are made of the metal materials described above, polyethylene, polypropylene, modified It is preferably composed of a polyolefin resin such as polyethylene or modified polypropylene.

Note that the exterior member 30 may be configured by another structure, for example, a laminate film not including a metal material, a polymer film such as polypropylene, or a metal film, instead of the above-described laminate film.
Here, the general structure of an exterior member can be represented by the laminated structure of an exterior layer / metal foil / sealant layer (however, the exterior layer and the sealant layer may be composed of a plurality of layers), and the above. In this example, the nylon film corresponds to the exterior layer, the aluminum foil corresponds to the metal foil, and the polyethylene film corresponds to the sealant layer.
In addition, as metal foil, it is sufficient if it functions as a moisture-permeable barrier film, and not only aluminum foil but also stainless steel foil, nickel foil and plated iron foil can be used, but it is thin and lightweight. Thus, an aluminum foil excellent in workability can be suitably used.

  The structures that can be used as the exterior member are listed in the form of (exterior layer / metal foil / sealant layer): Ny (nylon) / Al (aluminum) / CPP (unstretched polypropylene), PET (polyethylene terephthalate) / Al / CPP, PET / Al / PET / CPP, PET / Ny / Al / CPP, PET / Ny / Al / Ny / CPP, PET / Ny / Al / Ny / PE (polyethylene), Ny / PE / Al / LLDPE (direct) Chain low density polyethylene), PET / PE / Al / PET / LDPE (low density polyethylene), and PET / Ny / Al / LDPE / CPP.

  FIG. 2 is a cross-sectional view taken along the line II of the battery element 20 shown in FIG. In the figure, a battery element 20 is wound with a positive electrode 21 and a negative electrode 22 facing each other with a non-aqueous electrolyte composition layer 23 made of the non-aqueous electrolyte composition of the present invention and a separator 24 therebetween. The outermost peripheral part is protected by the protective tape 25.

Here, the positive electrode 21 has, for example, a structure in which a positive electrode active material layer 21B is coated on both surfaces or one surface of a positive electrode current collector 21A having a pair of opposed surfaces. The positive electrode current collector 21 </ b> A has a portion exposed without being covered with the positive electrode active material layer 21 </ b> B at one end portion in the longitudinal direction, and the positive electrode terminal 11 is attached to the exposed portion.
The positive electrode current collector 21A is made of a metal foil such as an aluminum foil, a nickel foil, or a stainless steel foil.

The positive electrode active material layer 21B includes one or more positive electrode materials capable of occluding and releasing lithium ions as a positive electrode active material, and a conductive material and a binder as necessary. May be included.
Examples of the positive electrode material capable of inserting and extracting lithium include sulfur (S), iron disulfide (FeS ₂ ), titanium disulfide (TiS ₂ ), molybdenum disulfide (MoS ₂ ), and niobium diselenide. lithium (NbSe _2), vanadium oxide _{(V 2 O} 5), chalcogenides containing no lithium, such as titanium dioxide (TiO ₂₎ and manganese dioxide (MnO ₂₎ (especially layered compound and the spinel-type compound), containing lithium Examples thereof include conductive compounds such as polyaniline, polythiophene, polyacetylene, and polypyrrole.

  Among these, lithium-containing compounds are preferable because some compounds can obtain a high voltage and a high energy density. Examples of such a lithium-containing compound include a composite oxide containing lithium and a transition metal element, and a phosphate compound containing lithium and a transition metal element. From the viewpoint of obtaining a higher voltage, cobalt is particularly preferred. (Co), nickel (Ni), manganese (Mn), iron (Fe), copper (Cu), zinc (Zn), chromium (Cr), vanadium (V), titanium (Ti) or any mixture thereof. The inclusion is preferred.

Such lithium-containing compounds are typically represented by the following general formula (17) or (18):
LiM ^I O ₂ (17)
Li _y M ^II PO ₄ (18)
(In the formula, M ^I and M ^II represent one or more transition metal elements, and the values of x and y vary depending on the charge / discharge state of the battery, but usually 0.05 ≦ x ≦ 1.10, 0.05 ≦ y ≦ 1.10), and the compound of the formula (17) generally has a layered structure, and the compound of the formula (18) generally has an olivine structure.

Specific examples of the composite oxide containing lithium and a transition metal element include lithium cobalt composite oxide (Li _x CoO ₂ ), lithium nickel composite oxide (LiNiO ₂ ), and solid solutions thereof (Li (Ni _x Co _y Mn _{z) O} 2), lithium nickel cobalt composite oxide _{(LiNi 1-z Co z O} 2 (z <1), lithium-manganese complex oxide having a spinel structure (LiMn ₂ O ₄₎ and their solid solutions ( _{li (Mn 2-x Ni y} ) O 4) , and the like.
Specific examples of the phosphate compound containing lithium and a transition metal element include, for example, a lithium iron phosphate compound (LiFePO ₄ ) or a lithium iron manganese phosphate compound (LiFe _1-v MnPO ₄ (v <1) having an olivine structure. ).

On the other hand, similarly to the positive electrode 21, the negative electrode 22 has a structure in which a negative electrode active material layer 22B is provided on both surfaces or one surface of a negative electrode current collector 22A having a pair of opposed surfaces, for example. The negative electrode current collector 22A has an exposed portion without being provided with the negative electrode active material layer 22B at one end in the longitudinal direction, and the negative electrode terminal 12 is attached to the exposed portion.
The anode current collector 22A is made of a metal foil such as a copper foil, a nickel foil, or a stainless steel foil.

The negative electrode active material layer 22B includes one or more of a negative electrode material capable of inserting and extracting lithium ions and metallic lithium as a negative electrode active material, and a conductive material and a binder as necessary. An adhesive may be included.
Examples of the negative electrode material capable of inserting and extracting lithium include a carbon material, a metal oxide, and a polymer compound. Examples of the carbon material include non-graphitizable carbon materials, artificial graphite materials, and graphite-based materials. More specifically, pyrolytic carbons, cokes, graphites, glassy carbons, organic polymer compound firing Body, carbon fiber, activated carbon and carbon black.
Among these, coke includes pitch coke, needle coke and petroleum coke, and the organic polymer compound fired body is carbonized by firing a polymer material such as phenol resin or furan resin at an appropriate temperature. Say things. In addition, examples of the metal oxide include iron oxide, ruthenium oxide, and molybdenum oxide, and examples of the polymer compound include polyacetylene and polypyrrole.

Further, examples of the negative electrode material capable of inserting and extracting lithium include a material containing as a constituent element at least one of a metal element and a metalloid element capable of forming an alloy with lithium. The negative electrode material may be a single element, alloy or compound of a metal element or a metalloid element, or may have at least a part of one or more of these phases.
In the present invention, alloys include those containing one or more metal elements and one or more metalloid elements in addition to those composed of two or more metal elements. Moreover, the nonmetallic element may be included. Some of the structures include a solid solution, a eutectic (eutectic mixture), an intermetallic compound, or a mixture of two or more of these.

Examples of such metal elements or metalloid elements include tin (Sn), lead (Pb), aluminum, indium (In), silicon (Si), zinc (Zn), antimony (Sb), bismuth (Bi), Examples include gallium (Ga), germanium (Ge), arsenic (As), silver (Ag), hafnium (Hf), zirconium (Zr), and yttrium (Y).
Among them, a group 14 metal element or metalloid element in the long-period type periodic table is preferable, and silicon or tin is particularly preferable. This is because silicon and tin have a large ability to occlude and release lithium, and a high energy density can be obtained.

Examples of the tin alloy include silicon, magnesium (Mg), nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium (Ti), germanium, bismuth, and antimony as second constituent elements other than tin. And at least one selected from the group consisting of chromium (Cr).
As an alloy of silicon, for example, as a second constituent element other than silicon, tin, magnesium, nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium, germanium, bismuth, antimony, and chromium can be used. The thing containing at least 1 sort (s) of them is mentioned.

  Examples of the tin compound or the silicon compound include those containing oxygen (O) or carbon (C), and may contain the second constituent element described above in addition to tin or silicon.

  The separator 24 has a high ion permeability and a predetermined mechanical strength, such as a porous film made of a polyolefin-based synthetic resin such as polypropylene or polyethylene, or a porous film made of an inorganic material such as a ceramic nonwoven fabric. It is good also as a structure which laminated | stacked these 2 or more types of porous films. In particular, those containing a polyolefin-based porous membrane are suitable because they have excellent separability between the positive electrode 21 and the negative electrode 22 and can further reduce internal short-circuiting and open circuit voltage reduction.

Next, an example of a method for manufacturing the secondary battery described above will be described.
The laminate type secondary battery can be manufactured as follows.
First, the positive electrode 21 is produced. For example, when a particulate positive electrode active material is used, a positive electrode mixture is prepared by mixing a positive electrode active material and, if necessary, a conductive material and a binder, and a dispersion medium such as N-methyl-2-pyrrolidone. To produce a positive electrode mixture slurry.
Next, the positive electrode mixture slurry is applied to the positive electrode current collector 21A, dried, and compression molded to form the positive electrode active material layer 21B.

  Moreover, the negative electrode 22 is produced. For example, when a particulate negative electrode active material is used, a negative electrode mixture is prepared by mixing a negative electrode active material and, if necessary, a conductive material and a binder, and a dispersion medium such as N-methyl-2-pyrrolidone. To prepare a negative electrode mixture slurry. Thereafter, the negative electrode mixture slurry is applied to the negative electrode current collector 22A, dried, and compression molded to form the negative electrode active material layer 22B.

  Next, after attaching the positive electrode terminal 11 to the positive electrode 21 and attaching the negative electrode terminal 12 to the negative electrode 22, the separator 24, the positive electrode 21, the separator 24, and the negative electrode 22 are sequentially stacked and wound, and the protective tape 25 is attached to the outermost peripheral portion. A wound electrode body is formed by bonding. Further, the wound electrode body is sandwiched between the exterior members 30, and the outer peripheral edge except one side is heat-sealed to form a bag shape.

  Thereafter, a non-aqueous electrolyte composition containing the above-described chain carbonate, an electrolyte salt such as lithium hexafluorophosphate, and a non-aqueous solvent such as ethylene carbonate is prepared and wound from the opening of the exterior member 30. It inject | pours into the inside of an electrode body, the opening part of the exterior member 30 is heat-sealed and sealed. Thereby, the nonaqueous electrolyte composition layer 23 is formed, and the secondary battery shown in FIGS. 1 and 2 is completed.

In addition, you may manufacture this secondary battery as follows.
For example, instead of injecting the nonaqueous electrolyte composition after producing the wound electrode body, the nonaqueous electrolyte composition is applied on the positive electrode 21 and the negative electrode 22 or the separator 24 and then wound, and the exterior member 30 is wound. You may make it enclose inside.

  In the secondary battery described above, when charged, lithium ions are released from the positive electrode active material layer 21 </ b> B and inserted into the negative electrode active material layer 22 </ b> B through the nonaqueous electrolyte composition layer 23. When discharge is performed, lithium ions are released from the negative electrode active material layer 22 </ b> B and inserted into the positive electrode active material layer 21 </ b> B through the nonaqueous electrolyte composition layer 23.

Here, the non-aqueous electrolyte composition contained in the non-aqueous electrolyte composition layer 23 is excellent in impregnation and permeability into the positive electrode active material layer 21B and the negative electrode active material 22B. Accordingly, since the electrolyte is sufficiently in contact with many active materials, the battery performance of the secondary battery is not greatly deteriorated during charging and discharging, and the discharge capacity maintenance rate during repeated charging and discharging is improved. .
Further, the non-aqueous electrolyte composition is effective in preventing battery swelling, and particularly when applied to a laminate film-covered battery and a thin prismatic battery in which measures for swelling of the battery exterior are more strongly demanded. It will be effective.

EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to these Examples.
Specifically, the operations described in the following examples were performed to produce a laminate type battery as shown in FIGS. 1 and 2, and its performance was evaluated.

Example 1
First, 94 parts by weight of lithium-cobalt composite oxide (LiCoO ₂ ) as a positive electrode active material, 3 parts by weight of graphite as a conductive material, and 3 parts by weight of polyvinylidene fluoride (PVdF) as a binder are homogeneous. After mixing, N-methylpyrrolidone was added to obtain a positive electrode mixture coating solution.
Next, the obtained positive electrode mixture coating solution was uniformly applied on both sides of an aluminum foil having a thickness of 20 μm and dried to form a positive electrode mixture layer of 40 mg / cm ² per side. This was cut into a shape having a width of 50 mm and a length of 300 mm to produce a positive electrode, and a positive electrode terminal was further attached.
Next, 97 parts by weight of graphite as a negative electrode active material and 3 parts by weight of PVdF as a binder were homogeneously mixed, and N-methylpyrrolidone was added to obtain a negative electrode mixture coating solution. Next, the obtained negative electrode mixture coating liquid was uniformly applied on both sides of a 15 μm-thick copper foil serving as a negative electrode current collector and dried to form a negative electrode mixture layer of 20 mg / cm ² per side. This was cut into a shape having a width of 50 mm and a length of 300 mm to prepare a negative electrode, and a negative electrode terminal was further attached.
Moreover, as a non-aqueous electrolyte composition, ethylene carbonate: propylene carbonate: diethyl carbonate: lithium hexafluorophosphate: ditetradecyl carbonate = 17: 8: 60: 14: 1 ratio (weight ratio), To this, 0.3% of 1,3-propene sultone was mixed and diethyl carbonate was reduced by that amount (diethyl carbonate: 59.7%).

  The positive electrode and the negative electrode were laminated and wound up via a separator made of a microporous polyethylene film having a thickness of 20 μm, and placed in a bag as an example of an exterior member made of an aluminum laminate film. After injecting 2 g of the non-aqueous electrolyte composition into the bag, the bag was heat-sealed to produce a laminate type battery. The capacity of this battery is 700 mAh.

  Table 1 shows the amount of swelling when the battery was charged for 3 hours at 700 mA at 23 ° C. and 4.2 V as the upper limit, and then stored at 90 ° C. for 4 hours.

Thus, by using a chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and sultone (cyclic sulfonate), the swelling amount when stored at 90 ° C. for 4 hours is as described later. It can be seen that this is an improvement over the battery of Comparative Example 1 using the nonaqueous electrolyte composition to which no sultone is added.
Further, by comparing this result with the results of Comparative Examples 1 to 3 described later, vinylene carbonate (a carbonate ester having a carbon-carbon double bond) is added if sultone is contained in an amount of 0.3% or more. Even if it is not, it turns out that sufficient swelling suppression effect is acquired.

(Example 2)
The same procedure as in Example 1 was repeated except that the concentration of 1,3-propene sultone in the nonaqueous electrolyte composition was changed to 0.1% (diethyl carbonate: 59.9%). Got. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the obtained results are shown in Table 1.
From Table 1, when the concentration of 1,3-propene sultone is 0.1%, the swelling amount after storage at 90 ° C. for 4 hours is lower than that in Example 1, but is improved from Comparative Example 1. I understand.

(Example 3)
The same procedure as in Example 1 was repeated except that the concentration of 1,3-propene sultone in the nonaqueous electrolyte composition was changed to 0.5% (diethyl carbonate: 59.5%). Got. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the obtained results are shown in Table 1.
From Table 1, it can be seen that the amount of swelling after storage at 90 ° C. for 4 hours is improved as compared with Example 1 by setting the concentration of 1,3-propene sultone to 0.5%.

Example 4
The same procedure as in Example 1 was repeated except that 1% of vinylene carbonate was added to the nonaqueous electrolyte composition and diethyl carbonate was reduced by that amount to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the obtained results are shown in Table 1.
From Table 1, in addition to the chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and sultone, in addition to the carbonate ester having a carbon-carbon double bond, 90 ° C. for 4 hours after storage It can be seen that the amount of swelling is further improved as compared with Example 1.

(Examples 5 to 10)
1,3-propene sultone in the non-aqueous electrolyte composition is replaced with other sultone (1,3-propane sultone, 1,3-butane sultone and toluene sultone), and unsaturated sulfone (divinyl sulfone, methyl vinyl sulfone and phenyl sulfone) The same operation as in Example 4 was repeated except that the laminate type batteries of Examples 5 to 10 were obtained. Similarly, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 1.
From Table 1, when a carbonic acid ester having a carbon-carbon double bond is used together with a chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms, sultone or unsaturated sulfone, after storage at 90 ° C. for 4 hours The amount of swelling is improved over Comparative Example 1 and the battery of Comparative Example 2 using a non-aqueous electrolyte composition to which vinylene carbonate is added without containing the chain carbonate and sultone as described later. You can see that.

(Examples 11 and 12)
As the predetermined chain carbonate ester, as shown in Table 1, the same operation as in Example 4 was repeated except that ditridecyl carbonate was used in Example 11 and dieicosyl carbonate was used in Example 12, and each Example was repeated. 11 and 12 laminated batteries were obtained. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the obtained results are shown in Table 1.
From Table 1, even if the type of chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms is changed, the amount of swelling after storage at 90 ° C. for 4 hours is improved to a level substantially equivalent to that in Example 4. I understand that.

(Example 13)
The same procedure as in Example 4 was repeated except that methyl tetradecyl carbonate was used as the predetermined chain ester carbonate to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the obtained results are shown in Table 1.
From Table 1, when an asymmetric carbonate having a hydrocarbon group having 13 to 20 carbon atoms and a carbonate having a sultone and a carbon-carbon double bond are used in combination, the amount of swelling after storage at 90 ° C. for 4 hours is compared. It can be seen that this is an improvement over the battery of Example 2.

(Comparative Example 1)
The same procedure as in Example 1 was repeated except that diethyl carbonate was increased by that amount without adding sultone to obtain a laminate type battery of this example. The amount of swelling was measured as described above, and the results obtained are shown in Table 1.
From Table 1, it can be seen that if the sultone is not added, the amount of swelling after storage at 90 ° C. for 4 hours deteriorates more than the above Examples 1-13.

(Comparative Example 2)
The same procedure as in Example 4 was repeated except that the amount of diethyl carbonate was increased without adding the chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and sultone, and the laminate type battery of this example Got. The amount of swelling was measured as described above, and the results obtained are shown in Table 1.
From Table 1, it can be seen that the swelling amount after storage at 90 ° C. for 4 hours is inferior to those of Examples 4 to 13 unless the predetermined chain carbonate and sultone are added.

(Comparative Example 3)
The same procedure as in Example 1 was repeated except that diethyl carbonate was increased by that amount without adding a chain carbonate ester having a hydrocarbon group having 13 to 20 carbon atoms and sultone. Got. The amount of swelling was measured as described above, and the results obtained are shown in Table 1.
From Table 1, it can be seen that if the predetermined chain carbonate and sultone are not added, the amount of swelling after storage at 90 ° C. for 4 hours is deteriorated as compared with Examples 1 to 13.

(Comparative Example 4)
The same procedure as in Example 4 was repeated except that didodecyl carbonate was used instead of ditetradecyl carbonate to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the obtained results are shown in Table 1.
From Table 1, even when a chain carbonate having a hydrocarbon group having 12 carbon atoms and a sultone, a carbonate having a carbon-carbon double bond is used in combination, the swelling amount after storage at 90 ° C. for 4 hours is: It turns out that it is not improving rather than the said comparative example 2.

(Comparative Example 5)
A laminated battery of this example was obtained by repeating the same operation as in Example 4 except that dihenicosyl carbonate was used instead of ditetradecyl carbonate. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the obtained results are shown in Table 1.
From Table 1, even when a chain carbonate having a hydrocarbon group having 21 carbon atoms and a sultone, a carbonate having a carbon-carbon double bond is used in combination, the swelling amount after storage at 90 ° C. for 4 hours is: It turns out that it is not improving rather than the said comparative example 2.

(Example 14)
The same procedure as in Example 1 was repeated except that 1% polyvinyl formal was added to the nonaqueous electrolyte composition to swell it, and diethyl carbonate was reduced accordingly, to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.

From Table 2, by using a chain carbonate ester having a hydrocarbon group having 13 to 20 carbon atoms and sultone, the amount of swelling when stored at 90 ° C. for 4 hours is a non-aqueous electrolyte to which no sultone is added. It turns out that it is improving rather than the battery of the comparative example 6 mentioned later using a composition.
And if this result is compared with the results of Comparative Examples 6 to 8 described later, by adding 0.3% or more of sultone, vinylene carbonate (a carbonic acid ester having a carbon-carbon double bond) is not added. However, it turns out that sufficient swelling suppression effect is acquired.

(Example 15)
The same procedure as in Example 14 was repeated, except that the concentration of 1,3-propene sultone in the nonaqueous electrolyte composition was changed to 0.1% (diethyl carbonate: 59.9%). Got. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.
From Table 2, when the concentration of 1,3-propene sultone is 0.1%, the swollen amount after storage at 90 ° C. for 4 hours is lower than that in Example 13, but is improved over Comparative Example 6. I understand that.

(Example 16)
The same procedure as in Example 14 was repeated, except that the concentration of 1,3-propene sultone in the nonaqueous electrolyte composition was changed to 0.5% (diethyl carbonate: 59.5%). Got. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.
From Table 2, it can be seen that by setting the concentration of 1,3-propene sultone to 0.5%, the amount of swelling after storage at 90 ° C. for 4 hours is improved as compared with Example 14.

(Example 17)
The same procedure as in Example 14 was repeated except that 1% vinylene carbonate was added to the non-aqueous electrolyte composition and diethyl carbonate was reduced by that amount to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.
From Table 2, in addition to a chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and a sultone, in addition to a carbonate having a carbon-carbon double bond, the amount of swelling after storage at 90 ° C. for 4 hours It can be seen that this is a further improvement over Example 14.

(Examples 18 to 23)
1,3-propene sultone in the non-aqueous electrolyte composition is replaced with other sultone (1,3-propane sultone, 1,3-butane sultone and toluene sultone), and unsaturated sulfone (divinyl sulfone, methyl vinyl sulfone and phenyl sulfone) The same operations as in Example 17 were repeated except that the laminate type batteries of Examples 18 to 23 were obtained. Similarly, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.
From Table 2, it is 90 degreeC-4 hours by using together the carbonate ester which has a carbon-carbon double bond with the chain carbonate ester which has a C13-C20 hydrocarbon group, sultone, or unsaturated sulfone. The amount of swelling after storage is improved as compared with Comparative Example 6 and the battery of Comparative Example 7 using a non-aqueous electrolyte composition added with vinylene carbonate without containing the chain carbonate ester and sultone. I understand that.

(Examples 24 and 25)
As shown in Table 2, as the predetermined chain ester carbonate, the same operation as in Example 17 was repeated except that ditridecyl carbonate was used in Example 24 and dieicosyl carbonate was used in Example 25. 24 and 25 laminated batteries were obtained. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.
From Table 2, even if the type of the chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms is changed, the amount of swelling after storage at 90 ° C. for 4 hours is improved to a level substantially equivalent to that in Example 17. I understand that.

(Example 26)
The same procedure as in Example 17 was repeated except that methyl tetradecyl carbonate was used as the predetermined chain ester carbonate to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.
From Table 2, when an asymmetric carbonate ester having a hydrocarbon group having 13 to 20 carbon atoms and sultone and a carbonate ester having a carbon-carbon double bond are used in combination, the amount of swelling after storage at 90 ° C. for 4 hours is compared. It can be seen that this is an improvement over the battery of Example 7.

(Comparative Example 6)
The same procedure as in Example 14 was repeated except that diethyl carbonate was increased by that amount without adding sultone to obtain a laminate type battery of this example. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 2.
From Table 2, it can be seen that if the sultone is not added, the swollen amount after storage at 90 ° C. for 4 hours deteriorates more than the above Examples 14 to 26.

(Comparative Example 7)
The same procedure as in Example 17 was repeated, except that the amount of diethyl carbonate was increased without adding the chain carbonate ester having a hydrocarbon group having 13 to 20 carbon atoms and sultone, and the laminate type battery of this example Got. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 2.
From Table 2, it can be seen that the swelling amount after storage at 90 ° C. for 4 hours is inferior to those of Examples 17 to 26 unless the predetermined chain carbonate and sultone are added.

(Comparative Example 8)
The same procedure as in Example 14 was repeated except that the amount of diethyl carbonate was increased without adding the chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and sultone, and the laminate type battery of this example Got. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 2.
From Table 2, it can be seen that if the predetermined chain carbonate and sultone are not added, the amount of swelling after storage at 90 ° C. for 4 hours deteriorates compared to Examples 14 to 26.

(Comparative Example 9)
A laminated battery of this example was obtained by repeating the same operation as in Example 17 except that didodecyl carbonate was used instead of ditetradecyl carbonate. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.
From Table 2, even when a chain carbonate having a hydrocarbon group having 12 carbon atoms and a sultone, a carbonate having a carbon-carbon double bond is used in combination, the swelling amount after storage at 90 ° C. for 4 hours is: It turns out that it is not improving rather than the said comparative example 7.

(Comparative Example 10)
A laminated battery of this example was obtained by repeating the same operation as in Example 17 except that dihenicosyl carbonate was used instead of ditetradecyl carbonate. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 2.
From Table 2, even when a chain carbonate having a hydrocarbon group with 21 carbon atoms and a sultone, a carbonate having a carbon-carbon double bond is used in combination, the amount of swelling after storage at 90 ° C. for 4 hours is: It turns out that it is not improving rather than the said comparative example 7.

(Example 27)
The same procedure as in Example 1 was repeated except that 1% polyacrylic acid ester was added to the nonaqueous electrolyte composition to swell it, and the amount of diethyl carbonate was reduced accordingly, to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.

From Table 3, by using a chain carbonate ester having a hydrocarbon group having 13 to 20 carbon atoms and sultone, the swelling amount when stored at 90 ° C. for 4 hours is the addition of sultone as described later. It can be seen that this is an improvement over the battery of Comparative Example 11 using no non-aqueous electrolyte composition.
Moreover, when this result is compared with the results of Comparative Examples 11 to 13, which will be described later, by adding 0.3% or more of sultone, a sufficient swelling suppression effect can be obtained even when vinylene carbonate is not added. I understand.

(Example 28)
The same procedure as in Example 27 was repeated, except that the concentration of 1,3-propene sultone in the nonaqueous electrolyte composition was changed to 0.1% (diethyl carbonate: 59.9%), and the laminate type battery of this example Got. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.
From Table 3, when the concentration of 1,3-propene sultone is 0.1%, the swollen amount after storage at 90 ° C. for 4 hours is lower than that in Example 27, but is improved over Comparative Example 11. I understand that.

(Example 29)
The same procedure as in Example 27 was repeated, except that the concentration of 1,3-propene sultone in the nonaqueous electrolyte composition was changed to 0.5% (diethyl carbonate: 59.5%). Got. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.
From Table 3, it can be seen that by setting the concentration of 1,3-propene sultone to 0.5%, the amount of swelling after storage at 90 ° C. for 4 hours is improved as compared with Example 27.

(Example 30)
The same procedure as in Example 27 was repeated except that 1% vinylene carbonate was added to the non-aqueous electrolyte composition and diethyl carbonate was reduced by that amount to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.
From Table 3, the amount of swelling after storage at 90 ° C. for 4 hours is carried out by using a carbonate ester having a double bond in addition to a chain carbonate ester having a hydrocarbon group having 13 to 20 carbon atoms and a sultone. It can be seen that this is a further improvement over Example 27.

(Examples 31-36)
1,3-propene sultone in the non-aqueous electrolyte composition is replaced with other sultone (1,3-propane sultone, 1,3-butane sultone and toluene sultone), and unsaturated sulfone (divinyl sulfone, methyl vinyl sulfone and phenyl sulfone) The same procedure as in Example 30 was repeated except that the laminate type battery of this example was obtained. Similarly, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.
From Table 3, by using together with a carbonic acid ester having a double bond together with a chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms, sultone or unsaturated sulfone, swelling after storage at 90 ° C. for 4 hours It can be seen that the amount is improved over Comparative Example 11 and the battery of Comparative Example 12 using a non-aqueous electrolyte composition to which vinylene carbonate is added without containing the chain carbonate ester and sultone.

(Examples 37 and 38)
As shown in Table 3, as the predetermined chain ester carbonate, the same operation as in Example 30 was repeated except that ditridecyl carbonate was used in Example 37 and dieicosyl carbonate was used in Example 38. 37 and 38 laminated batteries were obtained. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.
From Table 3, even if the type of chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms is changed, the swollen amount after storage at 90 ° C. for 4 hours is improved to a level substantially equivalent to that in Example 30. I understand that.

(Example 39)
The same procedure as in Example 30 was repeated except that methyl tetradecyl carbonate was used as the predetermined chain ester carbonate to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.
From Table 3, when an asymmetric carbonate having a hydrocarbon group having 13 to 20 carbon atoms and a carbonate having a sultone or carbon-carbon double bond are used in combination, the amount of swelling after storage at 90 ° C. for 4 hours is compared. It can be seen that this is an improvement over the battery of Example 12.

(Comparative Example 11)
The same procedure as in Example 27 was repeated except that diethyl carbonate was increased by that amount without adding sultone to obtain a laminate type battery of this example. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 3.
From Table 3, it can be seen that if the sultone is not added, the swollen amount after storage at 90 ° C. for 4 hours deteriorates more than the above Examples 27-39.

(Comparative Example 12)
The same procedure as in Example 30 was repeated, except that the amount of diethyl carbonate was increased without adding the chain carbonate ester having a hydrocarbon group having 13 to 20 carbon atoms and sultone, and the laminate type battery of this example Got. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 3.
From Table 3, it can be seen that the swelling amount after storage at 90 ° C. for 4 hours is inferior to those in Examples 30 to 39 unless the predetermined chain carbonate and sultone are added.

(Comparative Example 13)
The same procedure as in Example 27 was repeated except that the amount of diethyl carbonate was increased by that amount without adding a chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and sultone. Got. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 3.
From Table 3, it can be seen that when the predetermined chain carbonate and sultone are not added, the swollen amount after storage at 90 ° C. for 4 hours is deteriorated as compared with Examples 27 to 39.

(Comparative Example 14)
The laminated battery of this example was obtained by repeating the same operation as in Example 30 except that didodecyl carbonate was used instead of ditetradecyl carbonate. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.
From Table 3, even when a chain carbonate having a hydrocarbon group having 12 carbon atoms and a sultone, a carbonate having a carbon-carbon double bond is used in combination, the swelling amount after storage at 90 ° C. for 4 hours is: It turns out that it is not improving rather than the said comparative example 12.

(Comparative Example 15)
A laminated battery of this example was obtained by repeating the same operation as in Example 30 except that dihenicosyl carbonate was used instead of ditetradecyl carbonate. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 3.
From Table 3, even when a chain carbonate having a hydrocarbon group having 21 carbon atoms and a sultone, a carbonate having a carbon-carbon double bond is used in combination, the swelling amount after storage at 90 ° C. for 4 hours is: It turns out that it is not improving rather than the said comparative example 12.

(Example 40)
The same procedure as in Example 1 was repeated, except that 1% polyvinylidene fluoride was added to the nonaqueous electrolyte composition to swell it, and the amount of diethyl carbonate was reduced accordingly, to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 4.

From Table 4, by using a chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and sultone, the swelling amount when stored at 90 ° C. for 4 hours is the addition of sultone as described later. It can be seen that this is an improvement over the battery of Comparative Example 16 using no non-aqueous electrolyte composition.
And by comparing this result with the results of Comparative Examples 16 to 18 described later, it can be seen that if 0.3% or more of sultone is added, a sufficient swelling suppression effect can be obtained without adding vinylene carbonate. .

(Example 41)
The same procedure as in Example 40 was repeated, except that the concentration of 1,3-propene sultone in the nonaqueous electrolyte composition was changed to 0.1% (diethyl carbonate: 59.9%), and the laminate type battery of this example Got. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 4.
From Table 4, when the concentration of 1,3-propene sultone is 0.1%, the amount of swelling after storage at 90 ° C. for 4 hours is lower than that in Example 40, but is improved over Comparative Example 16. I understand.

(Example 42)
The same procedure as in Example 40 was repeated, except that the concentration of 1,3-propene sultone in the nonaqueous electrolyte composition was changed to 0.5% (diethyl carbonate: 59.5%). Got. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 4.
From Table 4, it can be seen that the swelling amount after storage at 90 ° C. for 4 hours is improved as compared with Example 40 by setting the concentration of 1,3-propene sultone to 0.5%.

(Example 43)
The same procedure as in Example 40 was repeated except that 1% of vinylene carbonate was added to the nonaqueous electrolyte composition and diethyl carbonate was reduced by that amount to obtain a laminate type battery of this example. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 4.
From Table 4, in addition to the chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and the sultone, when the carbonate having a double bond is used in combination, the swelling amount after storage at 90 ° C. for 4 hours is Example 40. It can be seen that this is further improved.

(Examples 44 to 49)
1,3-propene sultone in the non-aqueous electrolyte composition is replaced with other sultone (1,3-propane sultone, 1,3-butane sultone and toluene sultone), and unsaturated sulfone (divinyl sulfone, methyl vinyl sulfone and phenyl sulfone) A laminated battery of this example was obtained by repeating the same operation as in Example 43 except that the laminate type battery was changed. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 4.
From Table 4, by using together with a carbonic acid ester having a double bond together with a chain carbonic acid ester, sultone or unsaturated sulfone having a hydrocarbon group having 13 to 20 carbon atoms, swelling after storage at 90 ° C. for 4 hours It can be seen that the amount is improved over Comparative Example 16 and the battery of Comparative Example 17 using the non-aqueous electrolyte composition added with vinylene carbonate without containing the above-mentioned chain carbonate and sultone.

(Examples 50 and 51)
As shown in Table 4, as the predetermined chain ester carbonate, the same operation as in Example 43 was repeated except that ditridecyl carbonate was used in Example 50 and dieicosyl carbonate was used in Example 51. 50 and 51 laminated batteries were obtained. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 4.
From Table 4, even if the type of chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms is changed, the swollen amount after storage at 90 ° C. for 4 hours is improved to a level substantially equivalent to that in Example 43. I understand that.

(Example 52)
The same procedure as in Example 43 was repeated except that methyl tetradecyl carbonate was used as the predetermined chain carbonate, to obtain a laminate type battery of this example. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 4.
From Table 4, when an asymmetric carbonate ester having a hydrocarbon group having 13 to 20 carbon atoms and a carbonate ester having a sultone or carbon-carbon double bond are used in combination, the amount of swelling after storage at 90 ° C. for 4 hours is compared. It can be seen that this is an improvement over the battery of Example 17.

(Comparative Example 16)
The same procedure as in Example 40 was repeated except that diethyl carbonate was increased by that amount without adding sultone to obtain a laminate type battery of this example. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 4.
From Table 4, it can be seen that if the sultone is not added, the amount of swelling after storage at 90 ° C. for 4 hours deteriorates more than the above Examples 40-52.

(Comparative Example 17)
The same procedure as in Example 43 was repeated except that the amount of diethyl carbonate was increased by that amount without adding a chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and sultone, and the laminate type battery of this example Got. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 4.
From Table 4, it can be seen that when the predetermined chain carbonate and sultone are not added, the amount of swelling after storage at 90 ° C. for 4 hours is inferior to those of Examples 43 to 52.

(Comparative Example 18)
The same procedure as in Example 40 was repeated except that the amount of diethyl carbonate was increased by that amount without adding a chain carbonate having a hydrocarbon group having 13 to 20 carbon atoms and sultone. Got. The amount of swelling was measured in the same manner as described above, and the results obtained are shown in Table 4.
From Table 4, it can be seen that when the predetermined chain carbonate and sultone are not added, the amount of swelling after storage at 90 ° C. for 4 hours is deteriorated as compared with Examples 40 to 52.

(Comparative Example 19)
A laminated battery of this example was obtained by repeating the same operation as in Example 43 except that didodecyl carbonate was used instead of ditetradecyl carbonate. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 4.
From Table 4, even when a chain carbonate having a hydrocarbon group having 12 carbon atoms and a sultone, a carbonate having a carbon-carbon double bond is used in combination, the swelling amount after storage at 90 ° C. for 4 hours is: It turns out that it is not improving rather than the said comparative example 17.

(Comparative Example 20)
A laminated battery of this example was obtained by repeating the same operation as in Example 43 except that dihenicosyl carbonate was used instead of ditetradecyl carbonate. Similarly to the above, the amount of swelling when stored at 90 ° C. for 4 hours was measured, and the results obtained are shown in Table 4.
From Table 4, even when a chain carbonate having a hydrocarbon group having 21 carbon atoms and a sultone, a carbonate having a carbon-carbon double bond is used in combination, the swelling amount after storage at 90 ° C. for 4 hours is: It turns out that it is not improving rather than the said comparative example 17.

As mentioned above, although this invention was demonstrated with some embodiment and an Example, this invention is not limited to these, A various deformation | transformation is possible within the range of the summary of this invention.
For example, in the above-described embodiment, the case of including the battery element 20 in which the positive electrode 21 and the negative electrode 22 are stacked and wound has been described, but a flat battery element in which a pair of positive and negative electrodes are stacked, or a plurality of battery elements The present invention can also be applied to a case where a stacked battery element in which a positive electrode and a negative electrode are stacked is provided.
In the above embodiment, the case where the film-shaped exterior member 30 is used has been described. However, the battery having other shapes such as a so-called cylindrical shape, square shape, coin shape, and button shape using a can as the exterior member. Similarly, the present invention can be applied. Furthermore, it is applicable not only to a secondary battery but also to a primary battery.

  Furthermore, as described above, the present invention relates to a battery using lithium as an electrode reactant, but the technical idea of the present invention is that other alkali metals such as sodium (Na) or potassium (K), magnesium ( The present invention can also be applied to the case of using an alkaline earth metal such as Mg) or calcium (Ca), or another light metal such as aluminum.

It is one Embodiment of the nonaqueous electrolyte secondary battery of this invention, Comprising: It is a disassembled perspective view which shows an example of a laminate type battery. It is sectional drawing along the II line of the battery element shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Positive electrode terminal, 12 ... Negative electrode terminal, 20 ... Battery element, 21 ... Positive electrode, 21A ... Positive electrode collector, 21B ... Positive electrode active material layer, 22 ... Negative electrode, 22A ... Negative electrode collector, 22B ... Negative electrode active material layer , 23 ... Non-aqueous electrolyte composition layer, 24 ... Separator, 25 ... Protective tape, 30 ... Exterior member, 31 ... Adhesion film

Claims (6)

Electrolyte salt,
A non-aqueous solvent;
A chain carbonate having a hydrocarbon group having at least carbon atoms 13 to 20,
A sulfonyl compound of the cyclic sulfonic acid ester or consisting of sulfones having a multiple bond,
Contain,
The content of the chain carbonate ester is 0.1% by mass or more and 2% by mass or less with respect to the total mass of the nonaqueous electrolyte composition for a secondary battery,
The secondary battery is characterized in that the content of the sulfonyl compound is 0.1% by mass or more and 0.5% by mass or less based on the total mass of the nonaqueous electrolyte composition for secondary battery. use a non-aqueous electrolyte composition. Further containing another carbonic acid ester having a carbon-carbon double bond ,
The content of the other ester carbonate, second according to claim 1, characterized in that the total mass of the nonaqueous electrolyte composition for a secondary battery is 5 wt% or less than 0.05 wt% Nonaqueous electrolyte composition for secondary battery . The nonaqueous electrolyte composition for a secondary battery according to claim 1 or 2, further comprising a polymer compound. The non-aqueous electrolyte composition for a secondary battery according to claim 3, wherein the polymer compound is at least one selected from the group consisting of polyvinyl formal, polyacrylic acid ester and polyvinylidene fluoride. object. A positive electrode and a negative electrode using a material capable of inserting and extracting lithium ions as a positive electrode active material or a negative electrode active material;
A non-aqueous electrolyte composition;
A separator;
An exterior member for housing these;
A non-aqueous electrolyte secondary battery comprising:
The non-aqueous electrolyte composition comprises an electrolyte salt,
A non-aqueous solvent;
A chain carbonate having a hydrocarbon group having at least carbon atoms 13 to 20,
A sulfonyl compound of the cyclic sulfonic acid ester or consisting of sulfones having a multiple bond,
Contain,
The content of the chain carbonate ester is 0.1% by mass or more and 2% by mass or less with respect to the total mass of the nonaqueous electrolyte composition,
The non-aqueous electrolyte secondary battery is characterized in that the content of the sulfonyl compound is 0.1% by mass or more and 0.5% by mass or less with respect to the total mass of the non-aqueous electrolyte composition. .   6. The nonaqueous electrolyte secondary battery according to claim 5, wherein the exterior member is made of a laminate film.

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