JP2015156280A - Active material for secondary battery, electrode for secondary battery, secondary battery, battery pack, electric vehicle, electric power storage system, electric tool, and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a secondary battery capable of obtaining excellent battery characteristics.

SOLUTION: The secondary battery includes: a positive electrode; a negative electrode; and an electrolyte. The positive electrode contains a lithium-containing compound represented by Li₂Mn_xIr_1-xO₃ (x satisfies 0<x≤0.6)

COPYRIGHT: (C)2015,JPO&INPIT

Description

  The present technology relates to an active material used for a secondary battery, an electrode and a secondary battery using the active material, a battery pack, an electric vehicle, an electric power storage system, an electric tool, and an electronic device using the secondary battery.

  In recent years, various electronic devices such as mobile phones and personal digital assistants (PDAs) have become widespread, and further downsizing, weight reduction, and long life of the electronic devices have been demanded. Accordingly, as a power source, development of a battery, in particular, a secondary battery that is small and lightweight and capable of obtaining a high energy density is in progress.

  Recently, secondary batteries are not limited to the electronic devices described above, and are being studied for various uses. An example of this application is a battery pack that is detachably mounted on an electronic device, an electric vehicle such as an electric vehicle, an electric power storage system such as a household electric power server, and an electric tool such as an electric drill.

  Secondary batteries using various charge / discharge principles have been proposed to obtain battery capacity. Among them, secondary batteries that use occlusion / release of electrode reactants or precipitation dissolution of electrode reactants are attracting attention. . This is because higher energy density can be obtained than lead batteries and nickel cadmium batteries.

  The secondary battery includes an electrolyte solution together with a positive electrode and a negative electrode, and the positive electrode includes an active material (positive electrode active material) involved in a charge / discharge reaction. Since the composition of the positive electrode active material greatly affects the battery characteristics, various studies have been made on the composition of the positive electrode active material.

Specifically, in order to improve cycle characteristics and the like, a composite oxide containing lithium (Li) and iridium (Ir) as constituent elements is used as a positive electrode active material (see, for example, Patent Documents 1 and 2). .) This composite oxide is Li [Li _x Me _y M _z ] O _{2 + d} (Me is manganese (Mn) or the like, M is iridium or the like, x + y + z = 1, 0 <x <0.33, 0 <z <0 .1, 0 ≦ d ≦ 1). The composite oxide is yLi [Li _1/3 Me _2/3 ] O _2- (1-y) LiMe′O ₂ (Me is iridium, Me ′ is manganese, 0 <y ≦ 0.8) It is a compound represented by these.

JP 2009-206100 A Japanese Patent No. 5207714

  Electronic devices and the like are becoming more sophisticated and multifunctional. Accordingly, the usage frequency of electronic devices and the like is increasing, and therefore secondary batteries tend to be charged and discharged frequently. Therefore, there is still room for improvement regarding the battery characteristics of the secondary battery.

  The present technology has been made in view of such problems, and the purpose thereof is an active material for a secondary battery, an electrode for a secondary battery, a secondary battery, a battery pack, and an electric vehicle capable of obtaining excellent battery characteristics. It is to provide a power storage system, a power tool, and an electronic device.

  The active material for secondary batteries of this technique contains the lithium containing compound represented by Formula (1).

Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6)

  The electrode for a secondary battery of the present technology includes the above-described lithium-containing compound. Moreover, the secondary battery of this technique is equipped with electrolyte solution with a positive electrode and a negative electrode, and the positive electrode has the structure similar to the electrode for secondary batteries of this technique mentioned above.

  Each of the battery pack, the electric vehicle, the power storage system, the electric tool, and the electronic device of the present technology includes a secondary battery, and the secondary battery has the same configuration as the secondary battery of the present technology described above. .

  According to the active material for a secondary battery, the electrode for a secondary battery, or the secondary battery of the present technology, since the lithium-containing compound represented by the formula (1) is included, excellent battery characteristics can be obtained. Moreover, the same effect can be acquired also in the battery pack of this technique, an electric vehicle, an electric power storage system, an electric tool, or an electronic device.

It is sectional drawing showing the structure of the secondary battery (cylindrical type) of one Embodiment of this technique. It is sectional drawing which expands and represents a part of winding electrode body shown in FIG. It is a perspective view showing the structure of the other secondary battery (laminate film type) of one Embodiment of this technique. It is sectional drawing along the IV-IV line of the wound electrode body shown in FIG. It is a perspective view showing the structure of the application example (battery pack: single cell) of a secondary battery. It is a block diagram showing the structure of the battery pack shown in FIG. It is a block diagram showing the structure of the application example (battery pack: assembled battery) of a secondary battery. It is a block diagram showing the structure of the application example (electric vehicle) of a secondary battery. It is a block diagram showing the structure of the application example (electric power storage system) of a secondary battery. It is a block diagram showing the structure of the application example (electric tool) of a secondary battery. It is sectional drawing showing the structure of the secondary battery (coin type) for a test.

Hereinafter, embodiments of the present technology will be described in detail with reference to the drawings. The order of explanation is as follows.

1. Active material for secondary battery Secondary battery 2-1. Lithium ion secondary battery 2-1-1. Cylindrical type 2-1-2. Laminate film type 2-2. Lithium metal secondary battery Applications of secondary battery 3-1. Battery pack (single cell)
3-2. Battery pack (assembled battery)
3-3. Electric vehicle 3-4. Electric power storage system 3-5. Electric tool

<1. Secondary battery active material>
First, an active material for a secondary battery of the present technology (hereinafter referred to as “active material” or “active material of the present technology”) will be described.

  The active material demonstrated here is used for secondary batteries, such as a lithium secondary battery, for example. However, the type of secondary battery in which the active material is used is not limited to the lithium secondary battery. Moreover, an active material may be used as a positive electrode active material and may be used as a negative electrode active material.

  This active material contains any one kind or two or more kinds of lithium-containing compounds represented by the formula (1).

Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6)

The lithium-containing compound represented by the formula (1) is a composite oxide containing manganese and iridium as constituent elements together with lithium. More specifically, the lithium-containing compound is a compound in which a part of iridium is substituted with manganese in lithium iridate (Li ₂ IrO ₃ ).

  However, the atomic ratio of manganese, that is, the ratio of manganese replacing iridium is larger than 0 and within 0.6 or less, as is apparent from the range of values that x can take. This is because a high energy density is obtained and the discharge capacity is not easily lowered even if the charge / discharge reaction is repeated.

  Specifically, when x = 0, a part of iridium is not substituted with manganese, so that the energy density remains low and the discharge capacity is likely to decrease when charge and discharge are repeated.

  On the other hand, when x> 0.6, a part of iridium is substituted with manganese, but the content of manganese is too much with respect to the content of iridium. In this case, the crystal structure of the lithium-containing compound becomes unstable and the bulk density decreases. As a result, the energy density is reduced. In addition, in a layer containing an active material (a positive electrode active material layer or a negative electrode active material layer described later), the active material is easily peeled off, and thus the layer containing the active material is physically destabilized. Therefore, when charging and discharging are repeated, the discharge capacity is significantly reduced.

  On the other hand, when 0 <x ≦ 0.6, the crystal structure of the lithium-containing compound is stabilized and the bulk density increases, so the influence of the lithium-containing compound on the battery characteristics is specific. To improve. Thereby, an energy density becomes high. In addition, in the layer containing the active material, the active material is hardly peeled off, so that the layer containing the active material is physically stabilized. Therefore, even if charging / discharging is repeated, the discharge capacity is unlikely to decrease.

  The value of x that determines the ratio of iridium being replaced by manganese is not particularly limited as long as 0 <x ≦ 0.6. Among these, x preferably satisfies 0.02 ≦ x ≦ 0.6. This is because a higher effect can be obtained.

Specific examples of the lithium-containing compound include Li ₂ Mn _0.02 Ir _0.98 O ₃ , Li ₂ Mn _0.2 Ir _0.8 O ₃ , Li ₂ Mn _0.4 Ir _0.6 O ₃ and Li ₂ Mn _0.6 Ir _0.4 O ₃ . However, a lithium-containing compound having a composition other than the above may be used as long as x satisfies 0 <x ≦ 0.6.

  According to this active material, since the above-described lithium-containing compound is contained, as described above, a high energy density can be obtained, and even if the charge / discharge reaction is repeated, the discharge capacity is hardly reduced. Therefore, excellent battery characteristics can be obtained.

  In particular, if x satisfies 0.02 ≦ x ≦ 0.6, a higher effect can be obtained.

<2. Secondary battery>
Next, a secondary battery using the above active material of the present technology will be described.

<2-1. Lithium ion secondary battery>
The secondary battery described here is, for example, a lithium secondary battery (lithium ion secondary battery) in which the capacity of the positive electrode 21 is obtained by occlusion and release of lithium (lithium ions) that are electrode reactants.

<2-1-1. Cylindrical type>
Each of FIGS. 1 and 2 represents a cross-sectional configuration of a secondary battery according to an embodiment of the present technology. In FIG. 2, a part of the wound electrode body 20 illustrated in FIG. 1 is enlarged.

[Overall structure of secondary battery]
The secondary battery is, for example, a so-called cylindrical secondary battery, and a wound electrode body 20 and a pair of insulating plates 12 and 13 are accommodated in a substantially hollow cylindrical battery can 11. . The wound electrode body 20 is wound, for example, after the positive electrode 21 and the negative electrode 22 are laminated via the separator 23.

  The battery can 11 has a hollow structure in which one end is closed and the other end is opened. For example, any one of iron (Fe), aluminum (Al), and alloys thereof is used. Or it is formed by two or more types. Nickel (Ni) or the like may be plated on the surface of the battery can 11. The pair of insulating plates 12 and 13 are arranged so as to sandwich the wound electrode body 20 and to extend perpendicularly to the wound peripheral surface.

  Since the battery lid 14, the safety valve mechanism 15 and the heat sensitive resistance element (PTC element) 16 are caulked through the gasket 17 at the open end of the battery can 11, the battery can 11 is sealed. The battery lid 14 is formed of the same material as the battery can 11, for example. The safety valve mechanism 15 and the heat sensitive resistance element 16 are both provided inside the battery lid 14, and the safety valve mechanism 15 is electrically connected to the battery lid 14 via the heat sensitive resistance element 16. In the safety valve mechanism 15, the disk plate 15 </ b> A is reversed when the internal pressure becomes a certain level or more due to an internal short circuit or external heating. Thereby, the electrical connection between the battery lid 14 and the wound electrode body 20 is cut. In order to prevent abnormal heat generation due to a large current, the resistance of the heat sensitive resistor 16 increases as the temperature rises. The gasket 17 is formed of, for example, an insulating material, and asphalt or the like may be applied to the surface of the gasket 17.

  For example, a center pin 24 is inserted in the center of the wound electrode body 20. However, the center pin 24 may not be inserted into the center of the wound electrode body 20. For example, a positive electrode lead 25 formed of a conductive material such as aluminum is connected to the positive electrode 21, and a negative electrode lead 26 formed of a conductive material such as nickel is connected to the negative electrode 22. ing. The positive electrode lead 25 is welded to the safety valve mechanism 15 and is electrically connected to the battery lid 14. The negative electrode lead 26 is welded to the battery can 11 and is electrically connected to the battery can 11.

[Positive electrode]
The positive electrode 21 has a positive electrode active material layer 21B on one surface or both surfaces of a positive electrode current collector 21A. The positive electrode current collector 21A is formed of, for example, one or more of conductive materials such as aluminum, nickel, and stainless steel.

  The positive electrode active material layer 21B contains the active material of the present technology that can occlude and release lithium as the positive electrode active material. As described above, a high energy density can be obtained, and even if the charge / discharge reaction is repeated, the discharge capacity is hardly reduced.

  However, the positive electrode active material layer 21B may further include any one kind or two or more kinds of other materials such as a positive electrode binder and a positive electrode conductive agent.

  In addition, the positive electrode active material layer 21B may contain any one type or two or more types of other active materials with the active material of this technique as a positive electrode active material.

  The other active material is preferably, for example, another lithium-containing compound, and more specifically, preferably one or both of a lithium-containing composite oxide and a lithium-containing phosphate compound. This is because a high energy density can be obtained.

  The “lithium-containing composite oxide” is an oxide containing lithium and one or more elements (hereinafter referred to as “other elements”, excluding lithium) as constituent elements, and has a layered rock salt type crystal structure Alternatively, it has a spinel crystal structure. The “lithium-containing phosphate compound” is a phosphate compound containing lithium and one or more other elements as constituent elements and has an olivine type crystal structure.

  The kind of other element is not particularly limited as long as it is any one kind or two or more kinds of arbitrary elements. Especially, it is preferable that another element is any 1 type or 2 types or more of the elements which belong to 2nd group-15th group in a long-period type periodic table. More specifically, it is more preferable that the other element is any one kind or two or more kinds of metal elements among nickel (Ni), cobalt (Co), manganese (Mn), and iron (Fe). This is because a high voltage can be obtained.

  Especially, it is preferable that the lithium containing complex oxide which has a layered rock salt type crystal structure is any one type or two types or more of the compounds represented by each of Formula (2)-Formula (4).

_{Li a Mn (1-bc)} Ni b M11 c O (2-d) F e ··· (2)
(M11 is cobalt (Co), magnesium (Mg), aluminum (Al), boron (B), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), copper (Cu), zinc It is at least one of (Zn), zirconium (Zr), molybdenum (Mo), tin (Sn), calcium (Ca), strontium (Sr), and tungsten (W), and a to e are 0.8. ≦ a ≦ 1.2, 0 <b <0.5, 0 ≦ c ≦ 0.5, (b + c) <1, −0.1 ≦ d ≦ 0.2 and 0 ≦ e ≦ 0.1 are satisfied. However, the composition of lithium varies depending on the charge / discharge state, and a is the value of the fully discharged state.)

Li _a Ni _(1-b) M12 _b O _(2-c) F _d (3)
(M12 is cobalt (Co), manganese (Mn), magnesium (Mg), aluminum (Al), boron (B), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), copper It is at least one of (Cu), zinc (Zn), molybdenum (Mo), tin (Sn), calcium (Ca), strontium (Sr), and tungsten (W), and a to d are 0.8. ≦ a ≦ 1.2, 0.005 ≦ b ≦ 0.5, −0.1 ≦ c ≦ 0.2 and 0 ≦ d ≦ 0.1, provided that the composition of lithium depends on the charge / discharge state Unlikely, a is the value of the fully discharged state.)

Li _a Co _(1-b) M13 _b O _(2-c) F _d (4)
(M13 is nickel (Ni), manganese (Mn), magnesium (Mg), aluminum (Al), boron (B), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), copper It is at least one of (Cu), zinc (Zn), molybdenum (Mo), tin (Sn), calcium (Ca), strontium (Sr), and tungsten (W), and a to d are 0.8. ≦ a ≦ 1.2, 0 ≦ b <0.5, −0.1 ≦ c ≦ 0.2 and 0 ≦ d ≦ 0.1, provided that the composition of lithium varies depending on the charge / discharge state, a is the value of the fully discharged state.)

Specific examples of the lithium-containing composite oxide having a layered rock salt type crystal structure are LiNiO ₂ , LiCoO ₂ , LiCo _0.98 Al _0.01 Mg _0.01 O ₂ , LiNi _0.5 Co _0.2 Mn _0.3 O ₂ , LiNi _0.8 Co _0.15 Al _0.05 O _2. LiNi _0.33 Co _0.33 Mn _0.33 O ₂ , Li _1.2 Mn _0.52 Co _0.175 Ni _0.1 O ₂ and Li _1.15 (Mn _0.65 Ni _0.22 Co _0.13 ) O ₂ .

  The lithium-containing composite oxide having a spinel crystal structure is preferably one or more of the compounds represented by formula (5).

Li _a Mn _(2-b) M14 _b O _c F _d (5)
(M14 is cobalt (Co), nickel (Ni), magnesium (Mg), aluminum (Al), boron (B), titanium (Ti), vanadium (V), chromium (Cr), iron (Fe), copper It is at least one of (Cu), zinc (Zn), molybdenum (Mo), tin (Sn), calcium (Ca), strontium (Sr), and tungsten (W), and a to d are 0.9. ≦ a ≦ 1.1, 0 ≦ b ≦ 0.6, 3.7 ≦ c ≦ 4.1 and 0 ≦ d ≦ 0.1, provided that the composition of lithium differs depending on the charge / discharge state, and a Is the value of the fully discharged state.)

Specific examples of the lithium-containing composite oxide having a spinel crystal structure include LiMn ₂ O ₄ .

  The lithium-containing phosphate compound having an olivine type crystal structure is preferably any one or two or more of the compounds represented by the formula (6).

Li _a M15PO ₄ (6)
(M15 is cobalt (Co), manganese (Mn), iron (Fe), nickel (Ni), magnesium (Mg), aluminum (Al), boron (B), titanium (Ti), vanadium (V), niobium It is at least one of (Nb), copper (Cu), zinc (Zn), molybdenum (Mo), calcium (Ca), strontium (Sr), tungsten (W), and zirconium (Zr). 0.9 ≦ a ≦ 1.1, where the composition of lithium varies depending on the charge / discharge state, and a is the value of the complete discharge state.)

Specific examples of the lithium-containing phosphate compound having an olivine type crystal structure include LiFePO ₄ , LiMnPO ₄ , LiFe _0.5 Mn _0.5 PO _4, and LiFe _0.3 Mn _0.7 PO ₄ .

  Note that the lithium-containing composite oxide may be any one or two or more of the compounds represented by the formula (7).

(Li ₂ MnO ₃ ) _x (LiMnO ₂ ) _1-x (7)
(X satisfies 0 ≦ x ≦ 1, where the composition of lithium varies depending on the charge / discharge state, and x is the value of the complete discharge state.)

  In addition, the other active material may be, for example, any one kind or two or more kinds of oxides, disulfides, chalcogenides, conductive polymers, and the like. Examples of the oxide include titanium oxide, vanadium oxide, and manganese dioxide. Examples of the disulfide include titanium disulfide and molybdenum sulfide. An example of the chalcogenide is niobium selenide. Examples of the conductive polymer include sulfur, polyaniline, and polythiophene.

  The positive electrode binder contains, for example, any one or more of synthetic rubber and polymer material. Examples of the synthetic rubber include styrene butadiene rubber, fluorine rubber, and ethylene propylene diene. Examples of the polymer material include polyvinylidene fluoride and polyimide.

  The positive electrode conductive agent contains, for example, any one or more of carbon materials. Examples of the carbon material include graphite, carbon black, acetylene black, and ketjen black. Note that the positive electrode conductive agent may be a metal material, a conductive polymer, or the like as long as the material has conductivity.

[Negative electrode]
The negative electrode 22 has a negative electrode active material layer 22B on one surface or both surfaces of a negative electrode current collector 22A.

  The negative electrode current collector 22A is formed of, for example, a conductive material such as copper, nickel, and stainless steel. The surface of the negative electrode current collector 22A is preferably roughened. This is because the so-called anchor effect improves the adhesion of the negative electrode active material layer 22B to the negative electrode current collector 22A. In this case, the surface of the negative electrode current collector 22A only needs to be roughened at least in a region facing the negative electrode active material layer 22B. The roughening method is, for example, a method of forming fine particles using electrolytic treatment. This electrolytic treatment is a method of forming irregularities on the surface of the negative electrode current collector 22A by forming fine particles on the surface of the negative electrode current collector 22A using an electrolysis method in an electrolytic cell. A copper foil produced by an electrolytic method is generally called an electrolytic copper foil.

  The negative electrode active material layer 22B includes any one or more of negative electrode materials capable of occluding and releasing an electrode reactant as a negative electrode active material. However, the negative electrode active material layer 22B may further include any one or more of other materials such as a negative electrode binder and a negative electrode conductive agent. Note that details regarding the negative electrode binder and the negative electrode conductive agent are the same as, for example, details regarding the positive electrode binder and the positive electrode conductive agent.

  However, the chargeable capacity of the negative electrode material is preferably larger than the discharge capacity of the positive electrode 21 in order to prevent the electrode reactant from unintentionally depositing on the negative electrode 22 during charging. That is, it is preferable that the electrochemical equivalent of the negative electrode material capable of occluding and releasing the electrode reactant is larger than the electrochemical equivalent of the positive electrode 21. The electrode reactant deposited on the anode 22 is, for example, lithium metal when the electrode reactant is lithium.

  The negative electrode material is, for example, any one or more of carbon materials. This is because the crystal structure changes very little during the storage and release of the electrode reactant, so that a high energy density can be stably obtained. Moreover, since the carbon material also functions as a negative electrode conductive agent, the conductivity of the negative electrode active material layer 22B is improved.

  Examples of the carbon material include graphitizable carbon, non-graphitizable carbon, and graphite. However, the interplanar spacing of the (002) plane in non-graphitizable carbon is preferably 0.37 nm or more, and the interplanar spacing of the (002) plane in graphite is preferably 0.34 nm or less. More specifically, examples of the carbon material include pyrolytic carbons, cokes, glassy carbon fibers, organic polymer compound fired bodies, activated carbon, and carbon blacks. The cokes include pitch coke, needle coke, petroleum coke and the like. The organic polymer compound fired body is obtained by firing (carbonizing) a polymer compound such as a phenol resin and a furan resin at an appropriate temperature. In addition, the carbon material may be low crystalline carbon heat-treated at a temperature of about 1000 ° C. or less, or may be amorphous carbon. The shape of the carbon material may be any of a fibrous shape, a spherical shape, a granular shape, and a scale shape.

  The negative electrode material is, for example, a material (metal-based material) containing any one or more of metal elements and metalloid elements as constituent elements. This is because a high energy density can be obtained.

  The metal-based material may be any of a simple substance, an alloy, and a compound, or two or more of them, or a material having at least one of those one or two or more phases. However, the alloy includes a material including one or more metal elements and one or more metalloid elements in addition to a material composed of two or more metal elements. The alloy may contain a nonmetallic element. The structure of this metal material is, for example, a solid solution, a eutectic (eutectic mixture), an intermetallic compound, and two or more kinds of coexisting materials.

  The metal element and the metalloid element described above are, for example, any one kind or two or more kinds of metal elements and metalloid elements capable of forming an alloy with the electrode reactant. Specifically, for example, magnesium, boron, aluminum, gallium, indium (In), silicon, germanium (Ge), tin, lead (Pb), bismuth (Bi), cadmium (Cd), silver (Ag), zinc , Hafnium (Hf), zirconium, yttrium (Y), palladium (Pd), platinum (Pt), and the like.

  Among these, one or both of silicon and tin is preferable. This is because the ability to occlude and release the electrode reactant is excellent, so that a significantly high energy density can be obtained.

  The material containing one or both of silicon and tin as a constituent element may be any of a simple substance, an alloy and a compound of silicon, or any of a simple substance, an alloy and a compound of tin. It may be a kind or more, and may be a material having at least a part of one kind or two or more kinds of phases. The simple substance means a simple substance (which may contain a small amount of impurities) in a general sense, and does not necessarily mean 100% purity.

  The alloy of silicon is, for example, any one of tin, nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium, germanium, bismuth, antimony, chromium and the like as a constituent element other than silicon or Includes two or more. The compound of silicon contains, for example, one or more of carbon and oxygen as constituent elements other than silicon. In addition, the compound of silicon may contain any 1 type or 2 types or more of the series of elements demonstrated regarding the alloy of silicon as structural elements other than silicon, for example.

Specific examples of silicon alloys and silicon compounds are SiB ₄ , SiB ₆ , Mg ₂ Si, Ni ₂ Si, TiSi ₂ , MoSi ₂ , CoSi ₂ , NiSi ₂ , CaSi ₂ , CrSi ₂ , Cu ₅ Si, FeSi _2. MnSi ₂ , NbSi ₂ , TaSi ₂ , VSi ₂ , WSi ₂ , ZnSi ₂ , SiC, Si ₃ N ₄ , Si ₂ N ₂ O, SiO _v (0 <v ≦ 2), and LiSiO. Note that _v in SiO _v may be 0.2 <v <1.4.

  The alloy of tin, for example, as a constituent element other than tin, any one of silicon, nickel, copper, iron, cobalt, manganese, zinc, indium, silver, titanium, germanium, bismuth, antimony, chromium, etc. Includes two or more. The tin compound contains, for example, one or more of carbon and oxygen as constituent elements other than tin. In addition, the compound of tin may contain any 1 type in the series of elements demonstrated regarding the alloy of tin, or 2 or more types as structural elements other than tin, for example.

Specific examples of the tin alloy and the tin compound include SnO _w (0 <w ≦ 2), SnSiO ₃ , LiSnO, and Mg ₂ Sn.

  In particular, the material containing tin as a constituent element is preferably, for example, a material containing Sn (first constituent element) and the second and third constituent elements as constituent elements (Sn-containing material). The second constituent element is, for example, cobalt, iron, magnesium, titanium, vanadium, chromium, manganese, nickel, copper, zinc, gallium, zirconium, niobium, molybdenum, silver, indium, cesium (Ce), hafnium (Hf), Any one or more of tantalum, tungsten, bismuth, silicon and the like are included. The third constituent element includes, for example, any one or more of boron, carbon, aluminum, phosphorus (P), and the like. This is because when the Sn-containing material contains the second and third constituent elements, a high battery capacity and excellent cycle characteristics can be obtained.

  Especially, it is preferable that Sn containing material is a material (SnCoC containing material) which contains tin, cobalt, and carbon as a structural element. In this SnCoC-containing material, for example, the carbon content is 9.9 mass% to 29.7 mass%, and the content ratio of tin and cobalt (Co / (Sn + Co)) is 20 mass% to 70 mass%. . This is because a high energy density can be obtained.

  The SnCoC-containing material has a phase containing tin, cobalt, and carbon, and the phase is preferably low crystalline or amorphous. Since this phase is a reaction phase capable of reacting with the electrode reactant, excellent characteristics can be obtained due to the presence of the reaction phase. The half-width (diffraction angle 2θ) of the diffraction peak obtained by X-ray diffraction of this reaction phase is 1 ° or more when CuKα ray is used as the specific X-ray and the insertion speed is 1 ° / min. Is preferred. This is because the electrode reactant is occluded and released more smoothly and the reactivity with the electrolytic solution is reduced. In addition, the SnCoC-containing material may include a phase containing a simple substance or a part of each constituent element in addition to the low crystalline or amorphous phase.

  Whether the diffraction peak obtained by X-ray diffraction corresponds to the reaction phase capable of reacting with the electrode reactant can be determined by comparing the X-ray diffraction charts before and after the electrochemical reaction with the electrode reactant. Easy to judge. For example, if the position of the diffraction peak changes before and after the electrochemical reaction with the electrode reactant, it corresponds to a reaction phase that can react with the electrode reactant. In this case, for example, a diffraction peak of a low crystalline or amorphous reaction phase is observed between 2θ = 20 ° and 50 °. Such a reaction phase contains, for example, each of the above-described constituent elements, and is considered to be low crystallized or amorphous mainly due to the presence of carbon.

  In the SnCoC-containing material, it is preferable that at least a part of carbon that is a constituent element is bonded to a metal element or a metalloid element that is another constituent element. This is because aggregation or crystallization of tin or the like is suppressed. The bonding state of the elements can be confirmed using, for example, X-ray photoelectron spectroscopy (XPS). In a commercially available apparatus, for example, Al—Kα ray or Mg—Kα ray is used as the soft X-ray. When at least a part of carbon is bonded to a metal element, a metalloid element, or the like, the peak of the synthetic wave of carbon 1s orbital (C1s) appears in a region lower than 284.5 eV. It is assumed that the energy calibration is performed so that the peak of the 4f orbit (Au4f) of the gold atom is obtained at 84.0 eV. At this time, since surface-contaminated carbon is usually present on the surface of the substance, the C1s peak of the surface-contaminated carbon is set to 284.8 eV, and the peak is used as an energy reference. In the XPS measurement, the waveform of the C1s peak is obtained in a form including the surface contamination carbon peak and the carbon peak in the SnCoC-containing material. For this reason, for example, both peaks are separated by analyzing using commercially available software. In the waveform analysis, the position of the main peak existing on the lowest bound energy side is used as the energy reference (284.8 eV).

  This SnCoC-containing material is not limited to a material (SnCoC) whose constituent elements are only tin, cobalt, and carbon. This SnCoC-containing material is, for example, any one of silicon, iron, nickel, chromium, indium, niobium, germanium, titanium, molybdenum, aluminum, phosphorus, gallium, and bismuth in addition to tin, cobalt, and carbon One kind or two or more kinds may be included as constituent elements.

  In addition to the SnCoC-containing material, a material containing tin, cobalt, iron and carbon as constituent elements (SnCoFeC-containing material) is also preferable. The composition of the SnCoFeC-containing material is arbitrary. For example, when the iron content is set to be small, the carbon content is 9.9 mass% to 29.7 mass%, and the iron content is 0.3 mass% to 5.9 mass%. The content ratio of tin and cobalt (Co / (Sn + Co)) is 30% by mass to 70% by mass. When the iron content is set to be large, the carbon content is 11.9% to 29.7% by mass, and the ratio of the content of tin, cobalt and iron ((Co + Fe) / (Sn + Co + Fe)) Is 26.4% by mass to 48.5% by mass, and the content ratio of cobalt and iron (Co / (Co + Fe)) is 9.9% by mass to 79.5% by mass. This is because a high energy density can be obtained in such a composition range. Note that the physical properties (half-value width, etc.) of the SnCoFeC-containing material are the same as the above-described physical properties of the SnCoC-containing material.

  In addition, the negative electrode material may be any one kind or two or more kinds of metal oxides and polymer compounds, for example. Examples of the metal oxide include iron oxide, ruthenium oxide, and molybdenum oxide. Examples of the polymer compound include polyacetylene, polyaniline, and polypyrrole.

  Especially, it is preferable that the negative electrode material contains both a carbon material and a metal-type material for the following reasons.

  A metal-based material, particularly a material containing one or both of silicon and tin as a constituent element has an advantage of high theoretical capacity, but has a concern that it tends to violently expand and contract during an electrode reaction. On the other hand, the carbon material has the concern that the theoretical capacity is low, but has the advantage that it is difficult to expand and contract during the electrode reaction. Therefore, by using both the carbon material and the metal-based material, expansion and contraction during the electrode reaction are suppressed while obtaining a high theoretical capacity (in other words, battery capacity).

  The negative electrode active material layer 22B is formed by any one method or two or more methods among, for example, a coating method, a gas phase method, a liquid phase method, a thermal spray method, and a firing method (sintering method). The coating method is, for example, a method in which a particulate (powder) negative electrode active material is mixed with a negative electrode binder and the mixture is dispersed in a solvent such as an organic solvent and then applied to the negative electrode current collector 22A. is there. Examples of the vapor phase method include a physical deposition method and a chemical deposition method. More specifically, for example, a vacuum deposition method, a sputtering method, an ion plating method, a laser ablation method, a thermal chemical vapor deposition, a chemical vapor deposition (CVD) method, and a plasma chemical vapor deposition method. Examples of the liquid phase method include an electrolytic plating method and an electroless plating method. The thermal spraying method is a method of spraying a molten or semi-molten negative electrode active material onto the negative electrode current collector 22A. The firing method is, for example, a method in which a mixture dispersed in a solvent is applied to the negative electrode current collector 22A using a coating method and then heat-treated at a temperature higher than the melting point of the negative electrode binder or the like. As the firing method, for example, an atmosphere firing method, a reaction firing method, a hot press firing method, or the like can be used.

  In this secondary battery, as described above, in order to prevent unintentional deposition of the electrode reactant on the negative electrode 22 during charging, the electrochemical equivalent of the negative electrode material capable of occluding and releasing the electrode reactant is Greater than the electrochemical equivalent of the positive electrode. In addition, when the open circuit voltage (that is, the battery voltage) at the time of full charge is 4.25 V or more, compared with the case where it is 4.20 V, even if the same positive electrode active material is used, the electrode reactant per unit mass Since the release amount increases, the amounts of the positive electrode active material and the negative electrode active material are adjusted accordingly. Thereby, a high energy density is obtained.

[Separator]
The separator 23 separates the positive electrode 21 and the negative electrode 22 and allows lithium ions to pass through while preventing a short circuit of current caused by contact between the two electrodes. The separator 23 is, for example, a porous film made of synthetic resin or ceramic, and may be a laminated film in which two or more kinds of porous films are laminated. The synthetic resin is, for example, polytetrafluoroethylene, polypropylene, or polyethylene.

  In particular, the separator 23 may include, for example, the above-described porous film (base material layer) and a polymer compound layer provided on one or both surfaces of the base material layer. This is because the adhesion of the separator 23 to the positive electrode 21 and the negative electrode 22 is improved, so that the distortion of the wound electrode body 20 is suppressed. As a result, the decomposition reaction of the electrolytic solution is suppressed, and the leakage of the electrolytic solution impregnated in the base material layer is also suppressed. Therefore, the resistance is not easily increased even if charging and discharging are repeated, and the battery swelling is also suppressed. Is done.

  The polymer compound layer includes, for example, a polymer material such as polyvinylidene fluoride. This is because it has excellent physical strength and is electrochemically stable. However, the polymer material may be a material other than polyvinylidene fluoride. In the case of forming the polymer compound layer, for example, a solution in which a polymer material is dissolved is applied to the substrate layer, and then the substrate layer is dried. In addition, after immersing a base material layer in a solution, the base material layer may be dried.

[Electrolyte]
The wound electrode body 20 is impregnated with an electrolytic solution that is a liquid electrolyte. This electrolytic solution contains a solvent and an electrolyte salt. However, the electrolytic solution may further include any one or more of other materials such as additives.

  The solvent contains any one or more of nonaqueous solvents such as organic solvents. The electrolytic solution containing the nonaqueous solvent is a so-called nonaqueous electrolytic solution.

  Examples of the solvent include a cyclic carbonate ester, a chain carbonate ester, a lactone, a chain carboxylate ester, and a nitrile. This is because excellent battery capacity, cycle characteristics, storage characteristics, and the like can be obtained. Examples of the cyclic carbonate include ethylene carbonate, propylene carbonate, and butylene carbonate, and examples of the chain carbonate include dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, and methyl propyl carbonate. Examples of the lactone include γ-butyrolactone and γ-valerolactone. Examples of the carboxylic acid ester include methyl acetate, ethyl acetate, methyl propionate, ethyl propionate, methyl butyrate, methyl isobutyrate, methyl trimethyl acetate, and ethyl trimethyl acetate. Examples of nitriles include acetonitrile, glutaronitrile, adiponitrile, methoxyacetonitrile, and 3-methoxypropionitrile.

  In addition, examples of the solvent include 1,2-dimethoxyethane, tetrahydrofuran, 2-methyltetrahydrofuran, tetrahydropyran, 1,3-dioxolane, 4-methyl-1,3-dioxolane, 1,3-dioxane, 1,4 -Dioxane, N, N-dimethylformamide, N-methylpyrrolidinone, N-methyloxazolidinone, N, N'-dimethylimidazolidinone, nitromethane, nitroethane, sulfolane, trimethyl phosphate and dimethyl sulfoxide may be used. This is because similar advantages can be obtained.

  Among these, any one or two or more of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and ethyl methyl carbonate is preferable. This is because better battery capacity, cycle characteristics, storage characteristics, and the like can be obtained. In this case, high viscosity (high dielectric constant) solvents such as ethylene carbonate and propylene carbonate (for example, dielectric constant ε ≧ 30) and low viscosity solvents such as dimethyl carbonate, ethyl methyl carbonate and diethyl carbonate (for example, viscosity ≦ 1 mPas). -A combination with s) is more preferred. This is because the dissociation property of the electrolyte salt and the ion mobility are improved.

  In particular, the solvent may contain any one kind or two or more kinds of unsaturated cyclic carbonate, halogenated carbonate, sultone (cyclic sulfonate) and acid anhydride. This is because the chemical stability of the electrolytic solution is improved. The unsaturated cyclic carbonate is a cyclic carbonate having one or more unsaturated bonds (carbon-carbon double bonds), and examples thereof include vinylene carbonate, vinyl ethylene carbonate, and methylene ethylene carbonate. The halogenated carbonate is a cyclic or chain carbonate containing one or more halogens as a constituent element. Examples of the cyclic halogenated carbonate include 4-fluoro-1,3-dioxolan-2-one and 4,5-difluoro-1,3-dioxolan-2-one. Examples of the chain halogenated carbonate include fluoromethyl methyl carbonate, bis (fluoromethyl) carbonate, and difluoromethyl methyl carbonate. Examples of sultone include propane sultone and propene sultone. Examples of the acid anhydride include succinic anhydride, ethanedisulfonic anhydride, and anhydrous sulfobenzoic acid. However, the solvent may be a material other than the above.

  The electrolyte salt includes, for example, any one kind or two or more kinds of salts such as a lithium salt. However, the electrolyte salt may contain a salt other than the lithium salt, for example. Examples of the salt other than lithium include salts of light metals other than lithium.

Examples of the lithium salt include lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate (LiBF ₄ ), lithium perchlorate (LiClO ₄ ), lithium hexafluoroarsenate (LiAsF ₆ ), and tetraphenyl. Lithium borate (LiB (C ₆ H ₅ ) ₄ ), lithium methanesulfonate (LiCH ₃ SO ₃ ), lithium trifluoromethanesulfonate (LiCF ₃ SO ₃ ), lithium tetrachloroaluminate (LiAlCl ₄ ), hexafluoride Examples include dilithium silicate (Li ₂ SiF ₆ ), lithium chloride (LiCl), and lithium bromide (LiBr). This is because excellent battery capacity, cycle characteristics, storage characteristics, and the like can be obtained.

Among these, any one or two or more of LiPF ₆ , LiBF ₄ , LiClO ₄ and LiAsF ₆ are preferable, and LiPF ₆ is more preferable. This is because a higher effect can be obtained because the internal resistance is lowered. However, the electrolyte salt may be a salt other than the above.

  Although content of electrolyte salt is not specifically limited, Especially, it is preferable that they are 0.3 mol / kg-3.0 mol / kg with respect to a solvent. This is because high ionic conductivity is obtained.

[Operation of secondary battery]
This secondary battery operates as follows, for example.

  At the time of charging, lithium ions are released from the positive electrode 21, and the lithium ions are occluded in the negative electrode 22 through the electrolytic solution. On the other hand, at the time of discharging, lithium ions are released from the negative electrode 22, and the lithium ions are occluded in the positive electrode 21 through the electrolytic solution.

[Method for producing secondary battery]
This secondary battery is manufactured by the following procedure, for example.

  When producing the positive electrode 21, first, a positive electrode active material including the active material of the present technology and, if necessary, a positive electrode binder and a positive electrode conductive agent are mixed to obtain a positive electrode mixture. Subsequently, the positive electrode mixture is dispersed in an organic solvent or the like to obtain a paste-like positive electrode mixture slurry. Subsequently, after applying the positive electrode mixture slurry to both surfaces of the positive electrode current collector 21A, the positive electrode mixture slurry is dried to form the positive electrode active material layer 21B. Subsequently, the positive electrode active material layer 21B is compression-molded using a roll press or the like while heating the positive electrode active material layer 21B as necessary. In this case, compression molding may be repeated a plurality of times.

  When the negative electrode 22 is manufactured, the negative electrode active material layer 22B is formed on the negative electrode current collector 22A by the same procedure as that of the positive electrode 21 described above. Specifically, a negative electrode active material, a negative positive electrode binder, a negative electrode conductive agent, and the like are mixed to form a negative electrode mixture, and then the negative electrode mixture is dispersed in an organic solvent or the like to obtain a paste-like negative electrode A mixture slurry is obtained. Subsequently, after applying the negative electrode mixture slurry to both surfaces of the negative electrode current collector 22A, the negative electrode mixture slurry is dried to form the negative electrode active material layer 22B. Finally, the negative electrode active material layer 22B is compression molded using a roll press or the like.

  When the secondary battery is assembled using the positive electrode 21 and the negative electrode 22, the positive electrode lead 25 is attached to the positive electrode current collector 21A using a welding method or the like, and the negative electrode lead is connected to the negative electrode current collector 22A using a welding method or the like. 26 is attached. Subsequently, after the positive electrode 21 and the negative electrode 22 are stacked via the separator 23 and wound to produce the wound electrode body 20, the center pin 24 is inserted into the center of the wound electrode body 20. Subsequently, the spirally wound electrode body 20 is accommodated in the battery can 11 while the spirally wound electrode body 20 is sandwiched between the pair of insulating plates 12 and 13. In this case, the tip of the positive electrode lead 25 is attached to the safety valve mechanism 15 using a welding method or the like, and the tip of the negative electrode lead 26 is attached to the battery can 11 using a welding method or the like. Subsequently, an electrolytic solution is injected into the battery can 11 and the separator 23 is impregnated with the electrolytic solution. Subsequently, the battery lid 14, the safety valve mechanism 15, and the heat sensitive resistance element 16 are caulked to the opening end portion of the battery can 11 through the gasket 17.

[Operation and effect of secondary battery]
According to this cylindrical lithium ion secondary battery, since the positive electrode 21 contains the active material of the present technology as the positive electrode active material, a high energy density is obtained, and the discharge capacity is reduced even if the charge / discharge reaction is repeated. It becomes difficult to do. Therefore, excellent battery characteristics can be obtained. Other operations and effects are the same as those of the active material of the present technology.

<2-1-2. Laminate film type>
FIG. 3 illustrates an exploded perspective configuration of another secondary battery according to an embodiment of the present technology, and FIG. 4 illustrates an enlarged cross section taken along line IV-IV of the spirally wound electrode body 30 illustrated in FIG. 3. doing. In the following, the components of the cylindrical secondary battery already described will be referred to as needed.

[Overall structure of secondary battery]
The secondary battery described here is, for example, a so-called laminate film type lithium ion secondary battery.

  In this secondary battery, for example, as shown in FIGS. 3 and 4, the wound electrode body 30 is housed inside a film-shaped exterior member 40. The wound electrode body 30 is wound after the positive electrode 33 and the negative electrode 34 are stacked via the separator 35 and the electrolyte layer 36. A positive electrode lead 31 is attached to the positive electrode 33, and a negative electrode lead 32 is attached to the negative electrode 34. The outermost peripheral part of the wound electrode body 30 is protected by a protective tape 37.

  Each of the positive electrode lead 31 and the negative electrode lead 32 is led out in the same direction from the inside of the exterior member 40 toward the outside, for example. The positive electrode lead 31 is formed of any one type or two or more types of conductive materials such as aluminum. The negative electrode lead 32 is formed of any one type or two or more types of conductive materials such as copper, nickel, and stainless steel. These conductive materials have, for example, a thin plate shape or a mesh shape.

  The exterior member 40 is, for example, a single film that can be folded in the direction of the arrow R shown in FIG. 3, and a recess for accommodating the wound electrode body 30 is provided in a part of the exterior member 40. It has been. The exterior member 40 is, for example, a laminate film in which a fusion layer, a metal layer, and a surface protective layer are laminated in this order. In the manufacturing process of the secondary battery, after the exterior member 40 is folded so that the fusion layers face each other with the wound electrode body 30 therebetween, the outer peripheral edges of the fusion layers are fused. However, the exterior member 40 may be one in which two laminated films are bonded together with an adhesive or the like. The fusion layer is, for example, any one kind or two or more kinds of films such as polyethylene and polypropylene. The metal layer is, for example, one or more of aluminum foils. The surface protective layer is, for example, any one film or two or more films selected from nylon and polyethylene terephthalate.

  Especially, it is preferable that the exterior member 40 is an aluminum laminate film in which a polyethylene film, an aluminum foil, and a nylon film are laminated in this order. However, the exterior member 40 may be a laminate film having another laminated structure, a polymer film such as polypropylene, or a metal film.

  An adhesion film 41 is inserted between the exterior member 40 and the positive electrode lead 31 and the negative electrode lead 32 in order to prevent intrusion of outside air. The adhesion film 41 is formed of a material having adhesion to the positive electrode lead 31 and the negative electrode lead 32. The material having this adhesion is, for example, a polyolefin resin, and more specifically, any one or more of polyethylene, polypropylene, modified polyethylene, modified polypropylene, and the like.

  The positive electrode 33 has, for example, a positive electrode active material layer 33B on one side or both sides of the positive electrode current collector 33A, and the negative electrode 34 has, for example, a negative electrode active material layer 34B on one side or both sides of the negative electrode current collector 34A. Have. The configurations of the positive electrode current collector 33A, the positive electrode active material layer 33B, the negative electrode current collector 34A, and the negative electrode active material layer 34B are, for example, the positive electrode current collector 21A, the positive electrode active material layer 21B, the negative electrode current collector 22A, and The configuration is the same as that of each of the negative electrode active material layers 22B. The configuration of the separator 35 is the same as that of the separator 23, for example.

  The electrolyte layer 36 includes an electrolytic solution and a polymer compound, and the electrolyte solution is held by the polymer compound. The electrolyte layer 36 is a so-called gel electrolyte. This is because high ionic conductivity (for example, 1 mS / cm or more at room temperature) is obtained and leakage of the electrolytic solution is prevented. The electrolyte layer 36 may further contain other materials such as additives.

  Examples of the polymer compound include polyacrylonitrile, polyvinylidene fluoride, polytetrafluoroethylene, polyhexafluoropropylene, polyethylene oxide, polypropylene oxide, polyphosphazene, polysiloxane, polyvinyl fluoride, polyvinyl acetate, polyvinyl alcohol, polymethacryl It includes any one or more of methyl acid, polyacrylic acid, polymethacrylic acid, styrene-butadiene rubber, nitrile-butadiene rubber, polystyrene and polycarbonate. In addition, the polymer compound may be a copolymer. This copolymer is, for example, a copolymer of vinylidene fluoride and hexafluoropyrene. Among these, as the homopolymer, polyvinylidene fluoride is preferable, and as the copolymer, a copolymer of vinylidene fluoride and hexafluoropyrene is preferable. This is because it is electrochemically stable.

  The configuration of the electrolytic solution is the same as the configuration of the electrolytic solution used in, for example, a cylindrical secondary battery. However, in the electrolyte layer 36 which is a gel electrolyte, the solvent of the electrolytic solution is a wide concept including not only a liquid material but also a material having ion conductivity capable of dissociating the electrolyte salt. Therefore, when using a polymer compound having ion conductivity, the polymer compound is also included in the solvent.

  Instead of the gel electrolyte layer 36, the electrolytic solution may be used as it is. In this case, the wound electrode body 30 is impregnated with the electrolytic solution.

[Operation of secondary battery]
This secondary battery operates as follows, for example.

  At the time of charging, lithium ions are released from the positive electrode 33, and the lithium ions are occluded in the negative electrode 34 through the electrolyte layer 36. On the other hand, during discharge, lithium ions are released from the negative electrode 34 and the lithium ions are occluded in the positive electrode 33 through the electrolyte layer 36.

[Method for producing secondary battery]
The secondary battery provided with the gel electrolyte layer 36 is manufactured, for example, by the following three types of procedures.

  In the first procedure, the positive electrode 33 and the negative electrode 34 are manufactured by the same manufacturing procedure as that of the positive electrode 21 and the negative electrode 22. That is, when the positive electrode 33 is produced, the positive electrode active material layer 33B is formed on both surfaces of the positive electrode current collector 33A, and when the negative electrode 34 is produced, the negative electrode active material layer is formed on both surfaces of the negative electrode current collector 34A. 34B is formed. Subsequently, a precursor solution is prepared by mixing an electrolytic solution, a polymer compound, a solvent, and the like. This solvent is, for example, an organic solvent. Subsequently, after applying a precursor solution to each of the positive electrode 33 and the negative electrode 34, the precursor solution is dried to form a gel electrolyte layer 36. Subsequently, the positive electrode lead 31 is attached to the positive electrode current collector 33A using a welding method or the like, and the negative electrode lead 32 is attached to the negative electrode current collector 34A using a welding method or the like. Subsequently, after the positive electrode 33 and the negative electrode 34 are laminated via the separator 35 and wound to produce the wound electrode body 30, a protective tape 37 is attached to the outermost peripheral portion thereof. Subsequently, after folding the exterior member 40 so as to sandwich the wound electrode body 30, the outer peripheral edge portions of the exterior member 40 are bonded to each other by using a heat fusion method or the like, and wound around the interior of the exterior member 59. The electrode body 30 is encapsulated. In this case, the adhesion film 41 is inserted between the positive electrode lead 31 and the negative electrode lead 32 and the exterior member 40.

  In the second procedure, the positive electrode lead 31 is attached to the positive electrode 33 and the negative electrode lead 52 is attached to the negative electrode 34. Subsequently, the positive electrode 33 and the negative electrode 34 are stacked via the separator 35 and wound to produce a wound body that is a precursor of the wound electrode body 30, and then a protective tape 37 is provided on the outermost peripheral portion thereof. Paste. Subsequently, after folding the exterior member 40 so as to sandwich the spirally wound electrode body 30, the remaining outer peripheral edge portion excluding the outer peripheral edge portion of one side of the exterior member 40 is bonded using a heat fusion method or the like. Thus, the wound body is housed inside the bag-shaped exterior member 40. Subsequently, an electrolyte solution is prepared by mixing the electrolytic solution, a monomer that is a raw material of the polymer compound, a polymerization initiator, and other materials such as a polymerization inhibitor as necessary. Subsequently, after the electrolyte composition is injected into the bag-shaped exterior member 40, the exterior member 40 is sealed using a heat fusion method or the like. Subsequently, the monomer is thermally polymerized to form a polymer compound. Thereby, the gel electrolyte layer 36 is formed.

  In the third procedure, a wound body is produced and stored in the bag-shaped exterior member 40 in the same manner as in the second procedure described above except that the separator 35 coated with the polymer compound on both sides is used. The polymer compound applied to the separator 35 is, for example, a polymer (homopolymer, copolymer or multi-component copolymer) containing vinylidene fluoride as a component. Specifically, polyvinylidene fluoride, binary copolymers containing vinylidene fluoride and hexafluoropropylene as components, and ternary copolymers containing vinylidene fluoride, hexafluoropropylene and chlorotrifluoroethylene as components. Such as coalescence. In addition to the polymer containing vinylidene fluoride as a component, one or more other polymer compounds may be used. Subsequently, after the electrolytic solution is prepared and injected into the exterior member 40, the opening of the exterior member 40 is sealed using a thermal fusion method or the like. Subsequently, the exterior member 40 is heated while applying a load, and the separator 35 is brought into close contact with the positive electrode 33 and the negative electrode 34 through the polymer compound. As a result, the electrolytic solution is impregnated into the polymer compound and the polymer compound gels, so that the electrolyte layer 36 is formed.

  In the third procedure, the swelling of the secondary battery is suppressed more than in the first procedure. Further, in the third procedure, compared to the second procedure, the solvent and the monomer that is the raw material of the polymer compound hardly remain in the electrolyte layer 36, so that the formation process of the polymer compound is well controlled. For this reason, the positive electrode 33, the negative electrode 34, the separator 35, and the electrolyte layer 36 are sufficiently adhered.

[Operation and effect of secondary battery]
According to this laminated film type secondary battery, since the positive electrode 33 contains the active material of the present technology as the positive electrode active material, the same operation and effect as the cylindrical lithium secondary battery can be obtained.

<2-2. Lithium metal secondary battery>
The secondary battery described here is a cylindrical lithium secondary battery (lithium metal secondary battery) in which the capacity of the negative electrode 22 is expressed by precipitation and dissolution of lithium metal. This secondary battery has the same configuration as the above-described lithium ion secondary battery (cylindrical type) except that the negative electrode active material layer 22B is formed of lithium metal, and is manufactured by the same procedure. Is done.

  In this secondary battery, since lithium metal is used as the negative electrode active material, a high energy density can be obtained. The negative electrode active material layer 22B may already exist from the time of assembly, but does not exist at the time of assembly, and may be formed of lithium metal deposited during charging. Further, the negative electrode current collector 22A may be omitted by using the negative electrode active material layer 22B as a current collector.

  This secondary battery operates as follows, for example. At the time of charging, lithium ions are released from the positive electrode 21, and the lithium ions are deposited as lithium metal on the surface of the negative electrode current collector 22A through the electrolytic solution. At the time of discharge, lithium metal is eluted from the negative electrode active material layer 22B as lithium ions into the electrolytic solution, and the lithium ions are occluded in the positive electrode 21 through the electrolytic solution.

  According to this cylindrical lithium metal secondary battery, since the positive electrode 21 contains the active material of the present technology as the positive electrode active material, excellent battery characteristics can be obtained for the same reason as the lithium ion secondary battery. it can.

  Note that the configuration of the lithium metal secondary battery described here is not limited to the cylindrical secondary battery, and may be applied to a laminate film type secondary battery. In this case, the same effect can be obtained.

<3. Applications of secondary batteries>
Next, application examples of the above-described secondary battery will be described.

  The secondary battery can be used for machines, devices, instruments, devices, and systems (a collection of multiple devices) that can use the secondary battery as a power source for driving or a power storage source for storing power. There is no particular limitation. The secondary battery used as a power source may be a main power source (a power source used preferentially) or an auxiliary power source (a power source used in place of the main power source or switched from the main power source). When the secondary battery is used as an auxiliary power source, the type of the main power source is not limited to the secondary battery.

  Applications of the secondary battery are as follows, for example. Electronic devices (including portable electronic devices) such as video cameras, digital still cameras, mobile phones, notebook computers, cordless phones, headphone stereos, portable radios, portable televisions, and portable information terminals. It is a portable living device such as an electric shaver. Storage devices such as backup power supplies and memory cards. Electric tools such as electric drills and electric saws. It is a battery pack used for a notebook computer or the like as a detachable power source. Medical electronic devices such as pacemakers and hearing aids. An electric vehicle such as an electric vehicle (including a hybrid vehicle). It is an electric power storage system such as a home battery system that stores electric power in case of an emergency. Of course, applications other than those described above may be used.

  Especially, it is effective that a secondary battery is applied to a battery pack, an electric vehicle, an electric power storage system, an electric tool, an electronic device, and the like. This is because, since excellent battery characteristics are required, the performance can be effectively improved by using the secondary battery of the present technology. The battery pack is a power source using a secondary battery, and is a so-called assembled battery. An electric vehicle is a vehicle that operates (runs) using a secondary battery as a driving power source, and may be an automobile (such as a hybrid automobile) that includes a drive source other than the secondary battery as described above. The power storage system is a system that uses a secondary battery as a power storage source. For example, in a household power storage system, power is stored in a secondary battery, which is a power storage source, so that it is possible to use household electrical products using the power. An electric power tool is a tool in which a movable part (for example, a drill etc.) moves, using a secondary battery as a driving power source. An electronic device is a device that exhibits various functions using a secondary battery as a driving power source (power supply source).

  Here, some application examples of the secondary battery will be specifically described. In addition, since the structure of each application example demonstrated below is an example to the last, the structure can be changed suitably.

<3-1. Battery pack (single cell)>
FIG. 5 shows a perspective configuration of a battery pack using single cells, and FIG. 6 shows a block configuration of the battery pack shown in FIG. FIG. 5 shows a state where the battery pack is disassembled.

  The battery pack described here is a simple battery pack (so-called soft pack) using one secondary battery, and is mounted, for example, on an electronic device typified by a smartphone. For example, as shown in FIG. 5, the battery pack includes a power supply 111 that is a laminate film type secondary battery, and a circuit board 116 connected to the power supply 111. A positive electrode lead 112 and a negative electrode lead 113 are attached to the power source 111.

  A pair of adhesive tapes 118 and 119 are attached to both side surfaces of the power source 111. A protection circuit (PCM: Protection, Circuit, Module) is formed on the circuit board 116. The circuit board 116 is connected to the positive electrode 112 through the tab 114 and is connected to the negative electrode lead 113 through the tab 115. The circuit board 116 is connected to a lead wire 117 with a connector for external connection. In the state where the circuit board 116 is connected to the power supply 111, the circuit board 116 is protected from above and below by the label 120 and the insulating sheet 121. By attaching the label 120, the circuit board 116, the insulating sheet 121, and the like are fixed.

  Further, the battery pack includes a power source 111 and a circuit board 116 as shown in FIG. 6, for example. The circuit board 116 includes, for example, a control unit 121, a switch unit 122, a PTC 123, and a temperature detection unit 124. Since the power source 111 can be connected to the outside via the positive electrode terminal 125 and the negative electrode terminal 127, the power source 111 is charged / discharged via the positive electrode terminal 125 and the negative electrode terminal 127. The temperature detector 124 can detect the temperature using a temperature detection terminal (so-called T terminal) 126.

  The control unit 121 controls the operation of the entire battery pack (including the usage state of the power supply 111), and includes, for example, a central processing unit (CPU) and a memory.

  For example, when the battery voltage reaches the overcharge detection voltage, the control unit 121 disconnects the switch unit 122 so that the charging current does not flow through the current path of the power supply 111. For example, when a large current flows during charging, the control unit 121 disconnects the charging current by cutting the switch unit 122.

  In addition, for example, when the battery voltage reaches the overdischarge detection voltage, the control unit 121 disconnects the switch unit 122 so that the discharge current does not flow in the current path of the power supply 111. For example, when a large current flows during discharging, the control unit 121 cuts off the switch unit 122 and cuts off the discharging current.

  The overcharge detection voltage of the secondary battery is, for example, 4.20V ± 0.05V, and the overdischarge detection voltage is, for example, 2.4V ± 0.1V.

  The switch unit 122 switches the usage state of the power source 111 (whether the power source 111 can be connected to an external device) in accordance with an instruction from the control unit 121. The switch unit 122 includes, for example, a charge control switch and a discharge control switch. Each of the charge control switch and the discharge control switch is, for example, a semiconductor switch such as a field effect transistor (MOSFET) using a metal oxide semiconductor. The charge / discharge current is detected based on, for example, the ON resistance of the switch unit 122.

  The temperature detection unit 124 measures the temperature of the power supply 111 and outputs the measurement result to the control unit 121. For example, the temperature detection unit 124 includes a temperature detection element such as a thermistor. The measurement result by the temperature detection unit 124 is used when the control unit 121 performs charge / discharge control during abnormal heat generation, or when the control unit 121 performs correction processing when calculating the remaining capacity.

  The circuit board 116 may not include the PTC 123. In this case, a PTC element may be attached to the circuit board 116 separately.

<3-2. Battery Pack (Battery)>
FIG. 7 shows a block configuration of a battery pack using an assembled battery. The battery pack includes, for example, a control unit 61, a power source 62, a switch unit 63, a current measurement unit 64, a temperature detection unit 65, and a voltage detection unit in a housing 60 formed of a plastic material. 66, a switch control unit 67, a memory 68, a temperature detection element 69, a current detection resistor 70, a positive terminal 71 and a negative terminal 72.

  The control unit 61 controls the operation of the entire battery pack (including the usage state of the power supply 62), and includes, for example, a CPU. The power source 62 includes one or more secondary batteries (not shown). The power source 62 is, for example, an assembled battery including two or more secondary batteries, and the connection form of these secondary batteries may be in series, in parallel, or a mixture of both. For example, the power source 62 includes six secondary batteries connected in two parallel three series.

  The switch unit 63 switches the usage state of the power source 62 (whether or not the power source 62 can be connected to an external device) according to an instruction from the control unit 61. The switch unit 63 includes, for example, a charge control switch, a discharge control switch, a charging diode, a discharging diode (all not shown), and the like. The charge control switch and the discharge control switch are semiconductor switches such as a field effect transistor (MOSFET) using a metal oxide semiconductor, for example.

  The current measurement unit 64 measures current using the current detection resistor 70 and outputs the measurement result to the control unit 61. The temperature detection unit 65 measures the temperature using the temperature detection element 69 and outputs the measurement result to the control unit 61. This temperature measurement result is used, for example, when the control unit 61 performs charge / discharge control during abnormal heat generation, or when the control unit 61 performs correction processing when calculating the remaining capacity. The voltage detector 66 measures the voltage of the secondary battery in the power source 62, converts the measured voltage from analog to digital, and supplies the converted voltage to the controller 61.

  The switch control unit 67 controls the operation of the switch unit 63 in accordance with signals input from the current measurement unit 64 and the voltage detection unit 66.

  For example, when the battery voltage reaches the overcharge detection voltage, the switch control unit 67 disconnects the switch unit 63 (charge control switch) and controls the charging current not to flow through the current path of the power source 62. . As a result, the power source 62 can only discharge through the discharging diode. Note that the switch control unit 67 cuts off the charging current when a large current flows during charging, for example.

  Further, the switch control unit 67 disconnects the switch unit 63 (discharge control switch) so that the discharge current does not flow in the current path of the power source 62 when the battery voltage reaches the overdischarge detection voltage, for example. . As a result, the power source 62 can only be charged via the charging diode. In addition, the switch control part 67 interrupts | blocks a discharge current, for example, when a big current flows at the time of discharge.

  In the secondary battery, for example, the overcharge detection voltage is 4.20 V ± 0.05 V, and the overdischarge detection voltage is 2.4 V ± 0.1 V.

  The memory 68 is, for example, an EEPROM that is a nonvolatile memory. The memory 68 stores, for example, numerical values calculated by the control unit 61, secondary battery information (for example, internal resistance in an initial state) measured in the manufacturing process stage, and the like. If the full charge capacity of the secondary battery is stored in the memory 68, the control unit 61 can grasp information such as the remaining capacity.

  The temperature detection element 69 measures the temperature of the power source 62 and outputs the measurement result to the control unit 61, and is, for example, a thermistor.

  The positive electrode terminal 71 and the negative electrode terminal 72 are connected to an external device (for example, a notebook personal computer) operated using a battery pack, an external device (for example, a charger) used to charge the battery pack, or the like. Terminal. Charging / discharging of the power source 62 is performed via the positive terminal 71 and the negative terminal 72.

<3-3. Electric vehicle>
FIG. 8 shows a block configuration of a hybrid vehicle which is an example of an electric vehicle. This electric vehicle includes, for example, a control unit 74, an engine 75, a power source 76, a driving motor 77, a differential device 78, a generator 79, and a transmission 80 inside a metal casing 73. And a clutch 81, inverters 82 and 83, and various sensors 84. In addition, the electric vehicle includes, for example, a front wheel drive shaft 85 and a front wheel 86 connected to the differential device 78 and the transmission 80, and a rear wheel drive shaft 87 and a rear wheel 88.

  This electric vehicle can run, for example, using either the engine 75 or the motor 77 as a drive source. The engine 75 is a main power source, such as a gasoline engine. When the engine 75 is used as a power source, the driving force (rotational force) of the engine 75 is transmitted to the front wheels 86 or the rear wheels 88 via, for example, a differential device 78, a transmission 80, and a clutch 81 which are driving units. . The rotational force of the engine 75 is also transmitted to the generator 79, and the generator 79 generates AC power using the rotational force. The AC power is converted into DC power via the inverter 83, and the power source 76. On the other hand, when the motor 77 which is the conversion unit is used as a power source, the power (DC power) supplied from the power source 76 is converted into AC power via the inverter 82, and the motor 77 is driven using the AC power. . The driving force (rotational force) converted from electric power by the motor 77 is transmitted to the front wheels 86 or the rear wheels 88 via, for example, a differential device 78, a transmission 80, and a clutch 81, which are driving units.

  When the electric vehicle decelerates via a braking mechanism (not shown), the resistance force at the time of deceleration is transmitted as a rotational force to the motor 77, and the motor 77 generates AC power using the rotational force. Good. This AC power is preferably converted into DC power via the inverter 82, and the DC regenerative power is preferably stored in the power source 76.

  The control unit 74 controls the operation of the entire electric vehicle, and includes, for example, a CPU. The power source 76 includes one or more secondary batteries (not shown). The power source 76 may be connected to an external power source and can store power by receiving power supply from the external power source. The various sensors 84 are used, for example, to control the rotational speed of the engine 75 and to control the opening (throttle opening) of a throttle valve (not shown). The various sensors 84 include, for example, a speed sensor, an acceleration sensor, an engine speed sensor, and the like.

  Although the case where the electric vehicle is a hybrid vehicle has been described, the electric vehicle may be a vehicle (electric vehicle) that operates using only the power source 76 and the motor 77 without using the engine 75.

<3-4. Power storage system>
FIG. 9 shows a block configuration of the power storage system. This power storage system includes, for example, a control unit 90, a power source 91, a smart meter 92, and a power hub 93 in a house 89 such as a general house and a commercial building.

  Here, the power source 91 is connected to, for example, an electric device 94 installed in the house 89 and can be connected to an electric vehicle 96 stopped outside the house 89. The power source 91 is connected to, for example, a private generator 95 installed in a house 89 via a power hub 93 and can be connected to an external centralized power system 97 via a smart meter 92 and the power hub 93. is there.

  The electrical device 94 includes, for example, one or more home appliances, and the home appliances are, for example, a refrigerator, an air conditioner, a television, and a water heater. The private generator 95 is, for example, any one type or two types or more of a solar power generator and a wind power generator. The electric vehicle 96 is, for example, any one type or two or more types of electric vehicles, electric motorcycles, hybrid vehicles, and the like. The centralized power system 97 is, for example, any one type or two or more types among a thermal power plant, a nuclear power plant, a hydroelectric power plant, and a wind power plant.

  The control unit 90 controls the operation of the entire power storage system (including the usage state of the power supply 91), and includes, for example, a CPU. The power source 91 includes one or more secondary batteries (not shown). The smart meter 92 is, for example, a network-compatible power meter installed in a house 89 on the power demand side, and can communicate with the power supply side. Accordingly, for example, the smart meter 92 enables efficient and stable energy supply by controlling the balance between supply and demand in the house 89 while communicating with the outside.

  In this power storage system, for example, power is accumulated in the power source 91 from the centralized power system 97 that is an external power source via the smart meter 92 and the power hub 93, and from the private power generator 95 that is an independent power source via the power hub 93. Thus, electric power is accumulated in the power source 91. Since the electric power stored in the power supply 91 is supplied to the electric device 94 and the electric vehicle 96 in accordance with an instruction from the control unit 91, the electric device 94 can be operated and the electric vehicle 96 can be charged. . In other words, the power storage system is a system that makes it possible to store and supply power in the house 89 using the power source 91.

  The power stored in the power supply 91 can be used arbitrarily. For this reason, for example, power is stored in the power source 91 from the centralized power system 97 at midnight when the electricity usage fee is low, and the power stored in the power source 91 is used during the day when the electricity usage fee is high. it can.

  The power storage system described above may be installed for each house (one household), or may be installed for each of a plurality of houses (multiple households).

<3-5. Electric tool>
FIG. 10 shows a block configuration of the electric power tool. This electric tool is, for example, an electric drill, and includes a control unit 99 and a power supply 100 inside a tool main body 98 formed of a plastic material or the like. For example, a drill portion 101 which is a movable portion is attached to the tool body 98 so as to be operable (rotatable).

  The control part 99 controls operation | movement (including the use condition of the power supply 100) of the whole electric tool, and contains CPU etc., for example. The power supply 100 includes one or more secondary batteries (not shown). The control unit 99 supplies power from the power supply 100 to the drill unit 101 in response to an operation switch (not shown).

  Specific examples of the present technology will be described in detail.

(Experimental Examples 1-6)
The coin-type lithium ion secondary battery shown in FIG. 11 was produced as a test secondary battery by the following procedure. In this secondary battery, a test electrode 51 (positive electrode) and a counter electrode 53 (negative electrode) are laminated via a separator 55, and an outer can 52 in which the test electrode 51 is accommodated and an outer cup in which the counter electrode 53 is accommodated. 54 is caulked through a gasket 56.

In producing the test electrode 51, first, lithium carbonate (Li ₂ CO ₃ ), iridium oxide (IrO ₂ ), and manganese oxide (MnO ₂ ) were prepared as raw materials. Subsequently, after the raw materials were weighed, the weighed product was wet mixed with ethanol to obtain a precursor. Subsequently, after the precursor was fired (950 ° C.) under open air, the fired product was gradually cooled in a furnace. In this case, the heating rate was set to 200 ° C./hour and the holding time was set to 10 hours. Subsequently, the fired product was pulverized to obtain a lithium-containing compound (Li ₂ Mn _x Ir _1-x O ₃ ). The specific composition (value of x) of this lithium-containing compound is as shown in Table 1.

In addition, when obtaining a lithium containing compound, the mixing ratio (molar ratio) of the raw material was adjusted according to the composition of the lithium containing compound finally obtained. When Li ₂ IrO ₃ (x = 0) was obtained, Li ₂ CO ₃ : IrO ₂ = 1.05: 1 was set. When Li ₂ Mn _0.02 Ir _0.98 O ₃ (x = 0.02) was obtained, Li ₂ CO ₃ : IrO ₂ : MnO ₂ = 1.05: 0.98: 0.02. When Li ₂ Mn _0.2 Ir _0.8 O ₃ (x = 0.2) was obtained, Li ₂ CO ₃ : IrO ₂ : MnO ₂ = 1.05: 0.8: 0.2 was set. When Li ₂ Mn _0.4 Ir _0.6 O ₃ (x = 0.4) was obtained, Li ₂ CO ₃ : IrO ₂ : MnO ₂ = 1.05: 0.6: 0.4 was set. In the case of obtaining Li ₂ Mn _0.6 Ir _0.4 O ₃ (x = 0.6), Li ₂ CO ₃ : IrO ₂ : MnO ₂ = 1.05: 0.4: 0.6 was set. In the case of obtaining Li ₂ Mn _0.8 Ir _0.2 O ₃ (x = 0.8), Li ₂ CO ₃ : IrO ₂ : MnO ₂ = 1.05: 0.2: 0.8.

  The series of lithium-containing compounds described above was analyzed using SEM (scanning electron microscope) / EDX (energy dispersive X-ray spectroscopy) and XRD (X-ray diffraction). As a result, it was confirmed from the SEM / EDX image and the XRD pattern that each lithium-containing compound is substantially a single phase having the above-described composition. Moreover, when the bulk density of the lithium-containing compound was measured, the results shown in Table 1 were obtained. In Table 1, the value (converted value) converted into the bulk density of the lithium-containing compound of Experimental Example 3 (x = 0.2) as 100 is shown. In addition, the measuring method of a bulk density is based on JISK1469.

  Subsequently, 60 parts by mass of a positive electrode active material (lithium-containing compound), 10 parts by mass of a positive electrode binder (polyvinylidene fluoride), and 30 parts by mass of a positive electrode conductive agent (graphite) were mixed to obtain a positive electrode mixture. . As polyvinylidene fluoride, # 1300 manufactured by Kureha Co., Ltd. was used, and SuperP manufactured by Timcal Graphite & Carbon Co. was used as graphite. Subsequently, the positive electrode mixture was dispersed in an organic solvent (N-methyl-2-pyrrolidone) to obtain a paste-like positive electrode mixture slurry. Subsequently, a positive electrode mixture slurry was applied to both surfaces of a positive electrode current collector (20 μm-thick striped aluminum foil) using a coating apparatus, and then the positive electrode mixture slurry was dried to form a positive electrode active material layer. Finally, the positive electrode active material layer was compression molded using a roll press.

  As the counter electrode 53, a lithium metal plate was used.

In preparing the electrolytic solution, an electrolyte salt (LiPF ₆ ) was dissolved in a mixed solvent of ethylene carbonate (EC) and dimethyl carbonate (DMC). In this case, the mixing ratio (volume ratio) of the mixed solvent was EC: DMC = 30: 70, and the content of the electrolyte salt was 1 mol / kg with respect to the mixed solvent.

  When assembling the secondary battery, the test electrode 51 was punched into a pellet and the test electrode 51 was accommodated in an outer can 52. Subsequently, after punching the counter electrode 53 into a pellet, the counter electrode 53 was accommodated in the exterior cup 54. Subsequently, the test electrode 51 accommodated in the outer can 52 and the counter electrode 53 accommodated in the outer cup 54 are laminated via a separator 55 (a microporous polypropylene microporous film having a thickness of 23 μm), and then a gasket. The outer can 52 and the outer cup 54 were caulked through 56. Thereby, a coin-type secondary battery was completed.

  As the battery characteristics of the secondary battery, the initial capacity characteristics and the cycle characteristics were examined. The results shown in Table 1 were obtained.

When examining the initial capacity characteristics, first, in order to stabilize the battery state, the secondary battery was charged and discharged in one cycle in a normal temperature environment (23 ° C.). Subsequently, the secondary battery was charged and discharged again in the same environment, and the discharge capacity at the second cycle (initial capacity: mAh) was measured. At the time of charging, then the battery voltage at a current density of 0.47mA / cm ² was charged until it reaches the 4.35V, was charged until the current density remains the battery voltage reaches 0.047mA / cm ² . During discharging, discharging was performed at a current density of 0.47 mA / cm ² until the battery voltage reached 2V.

  When examining the cycle characteristics, the discharge capacity at the second cycle is measured by the same procedure as that for examining the initial capacity characteristics described above, and then the total number of cycles is 25 cycles under the same charge / discharge conditions in the same environment. The secondary battery was charged and discharged until it reached, and the discharge capacity at the 25th cycle was measured. From these measurement results, capacity retention ratio (%) = (25th cycle discharge capacity / second cycle discharge capacity) × 100 was calculated.

  The initial capacity and capacity retention ratio varied greatly depending on the composition of the lithium-containing compound.

  Specifically, when the lithium-containing compound did not contain manganese as a constituent element (Experimental Example 1), both the initial capacity and the capacity retention rate were low.

  Further, even when the lithium-containing compound contains manganese as a constituent element, when the manganese content is too large (Experimental Example 6), not only the initial capacity is lowered, but also the capacity retention rate is drastically reduced.

  On the other hand, when the lithium-containing compound contains manganese as a constituent element and the manganese content is appropriate (Experimental Examples 2 to 5), both the initial capacity and the cycle capacity were high. The case where the manganese content is an appropriate amount is a case where x satisfies 0 <x ≦ 0.6, and preferably a case where 0.02 ≦ x ≦ 0.6.

  When x satisfies 0 <x ≦ 0.6, a high bulk density is obtained, and more specifically, a bulk density equivalent to that when x = 0 is maintained.

From the results in Table 1, when the positive electrode contains a lithium-containing compound represented by Li ₂ Mn _x Ir _1-x O ₃ (0 <x ≦ 0.6), the initial capacity characteristics and the cycle characteristics are improved. . Therefore, excellent battery characteristics were obtained.

  As mentioned above, although this technique was demonstrated, giving an embodiment and an Example, this technique is not limited to the aspect demonstrated in embodiment and an Example, A various deformation | transformation is possible.

  For example, the case where the battery structure is a cylindrical type and the laminate film type is described as an example, and the case where the battery element has a winding structure is described as an example, but the present invention is not limited thereto. The secondary battery according to the present technology can be similarly applied to a case where other battery structures such as a square shape, a coin shape, and a button shape are provided, and a case where a battery element has another structure such as a laminated structure.

  Further, for example, the electrode reactant may be another group 1 element such as sodium (Na) and potassium (K), a group 2 element such as magnesium and calcium, or another light metal such as aluminum. Since the effect of the present technology should be obtained without depending on the type of the electrode reactant, the same effect can be obtained even if the type of the electrode reactant is changed.

In addition, this technique can also take the following structures.
(1)
An electrolyte is provided together with the positive electrode and the negative electrode,
The positive electrode includes a lithium-containing compound represented by the formula (1).
Secondary battery.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6)
(2)
X satisfies 0.02 ≦ x ≦ 0.6.
The secondary battery as described in said (1).
(3)
The lithium-containing compound includes at least one of Li ₂ Mn _0.02 Ir _0.98 O ₃ , Li ₂ Mn _0.2 Ir _0.8 O ₃ , Li ₂ Mn _0.4 Ir _0.6 O ₃ and Li ₂ Mn _0.6 Ir _0.4 O ₃ .
The secondary battery according to (1) or (2) above.
(4)
Lithium secondary battery,
The secondary battery according to any one of (1) to (3).
(5)
Including a lithium-containing compound represented by formula (1),
Secondary battery electrode.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6)
(6)
Including a lithium-containing compound represented by formula (1),
Active material for secondary batteries.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6)
(7)
The secondary battery according to any one of (1) to (4) above;
A control unit for controlling the operation of the secondary battery;
A battery pack comprising: a switch unit that switches the operation of the secondary battery in accordance with an instruction from the control unit.
(8)
The secondary battery according to any one of (1) to (4) above;
A converter that converts electric power supplied from the secondary battery into driving force;
A drive unit that drives according to the driving force;
An electric vehicle comprising: a control unit that controls the operation of the secondary battery.
(9)
The secondary battery according to any one of (1) to (4) above;
One or more electric devices supplied with power from the secondary battery;
And a control unit that controls power supply from the secondary battery to the electrical device.
(10)
The secondary battery according to any one of (1) to (4) above;
And a movable part to which electric power is supplied from the secondary battery.
(11)
An electronic device comprising the secondary battery according to any one of (1) to (4) as a power supply source.

  DESCRIPTION OF SYMBOLS 11 ... Battery can, 20, 30 ... Winding electrode body, 21, 33 ... Positive electrode, 21A, 33A ... Positive electrode collector, 21B, 33B ... Positive electrode active material layer, 22, 34 ... Negative electrode, 22A, 34A ... Negative electrode collection Electrical body, 22B, 34B ... negative electrode active material layer, 23, 35 ... separator, 36 ... electrolyte layer, 40 ... exterior member.

Claims (11)

An electrolyte is provided together with the positive electrode and the negative electrode,
The positive electrode includes a lithium-containing compound represented by the formula (1).
Secondary battery.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6) X satisfies 0.02 ≦ x ≦ 0.6.
The secondary battery according to claim 1. The lithium-containing compound includes at least one of Li ₂ Mn _0.02 Ir _0.98 O ₃ , Li ₂ Mn _0.2 Ir _0.8 O ₃ , Li ₂ Mn _0.4 Ir _0.6 O ₃ and Li ₂ Mn _0.6 Ir _0.4 O ₃ .
The secondary battery according to claim 1. Lithium secondary battery,
The secondary battery according to claim 1. Including a lithium-containing compound represented by formula (1),
Secondary battery electrode.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6) Including a lithium-containing compound represented by formula (1),
Active material for secondary batteries.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6) A secondary battery,
A control unit for controlling the operation of the secondary battery;
A switch unit for switching the operation of the secondary battery according to an instruction of the control unit,
The secondary battery includes an electrolyte solution together with a positive electrode and a negative electrode,
The positive electrode includes a lithium-containing compound represented by the formula (1).
Battery pack.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6) A secondary battery,
A converter that converts electric power supplied from the secondary battery into driving force;
A drive unit that drives according to the driving force;
A control unit for controlling the operation of the secondary battery,
The secondary battery includes an electrolyte solution together with a positive electrode and a negative electrode,
The positive electrode includes a lithium-containing compound represented by the formula (1).
Electric vehicle.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6) A secondary battery,
One or more electric devices supplied with power from the secondary battery;
A control unit for controlling power supply from the secondary battery to the electrical device,
The secondary battery includes an electrolyte solution together with a positive electrode and a negative electrode,
The positive electrode includes a lithium-containing compound represented by the formula (1).
Power storage system.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6) A secondary battery,
A movable part to which electric power is supplied from the secondary battery,
The secondary battery includes an electrolyte solution together with a positive electrode and a negative electrode,
The positive electrode includes a lithium-containing compound represented by the formula (1).
Electric tool.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6) A secondary battery is provided as a power supply source,
The secondary battery includes an electrolyte solution together with a positive electrode and a negative electrode,
The positive electrode includes a lithium-containing compound represented by the formula (1).
Electronics.
Li ₂ Mn _x Ir _1-x O ₃ (1)
(X satisfies 0 <x ≦ 0.6)

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