JP2014017071A - Secondary battery, battery pack, electric vehicle, power storage system, electric tool and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a secondary battery ensuring excellent battery characteristics.SOLUTION: A positive electrode contains a lithium-containing compound. The lithium-containing compound contains at least one of LiM1POand Li(MnNiCoM2)Oand the average primary particle size of the lithium-containing compound is 0.05-1 μm. A separator includes a porous base material layer, and a polymer compound layer. The polymer compound layer contains a polymer material applied to at least one of a surface of the base material layer facing the positive electrode and a surface facing the negative electrode, and into which particles of an inorganic oxide are dispersed. The average primary particle size of the inorganic oxide is 0.01-5 μm.

Description

  The present technology relates to a secondary battery provided with an electrolyte together with a positive electrode and a negative electrode opposed via a separator, and 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 reduction in size, weight, and life of the electrical devices are desired. 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, the secondary battery is not limited to the above-described electronic device, and application to various other uses is also being studied. Typical examples of other applications are battery packs that are detachably mounted on electronic devices, electric vehicles such as electric vehicles, power storage systems such as household power servers, or electric tools such as electric drills.

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

  The secondary battery includes an electrolytic solution together with a positive electrode and a negative electrode facing each other via a separator, and the positive electrode includes a positive electrode active material involved in a charge / discharge reaction. Since the configuration of the secondary battery greatly affects the battery characteristics, various studies have been made on the configuration.

Specifically, olivine type lithium iron phosphate (particle size = 10 nm to 150 nm) is used together with the carbon black composite (fibrous carbon and carbon black) in order to prolong the life due to charging and discharging with a large current. (For example, refer to Patent Document 1). In order to obtain excellent charge / discharge characteristics, a flaky lithium metal phosphate compound (thickness = 10 nm to 500 nm) represented by the general formula Li _x A _y PO ₄ is used (for example, see Patent Document 2). .) In the formula, A is Mn or the like and satisfies 0 <x <2 and 0 <y ≦ 1.

  In order to obtain excellent reliability even when charging / discharging at a high voltage, an insulating layer containing aluminum fluoride is provided between the positive electrode and the resin layer (see, for example, Patent Document 3). In order to improve battery characteristics even when a charging voltage exceeding 4.2 V is set, a separator including a surface layer such as polyvinylidene fluoride is used on the side facing the positive electrode (see, for example, Patent Document 4). In order to suppress deterioration of battery characteristics, a separator in which a resin layer containing an inorganic material is applied and formed on the surface of a base material layer is used (see, for example, Patent Document 5). In order to obtain excellent safety in a high temperature environment, a separator containing heat-resistant fine particles and a thermoplastic resin is used (for example, see Patent Document 6). The heat-resistant fine particles include particles having a particle size of 0.2 μm or less and particles having a particle size of 2 μm or more, and the ratio of these particles is 10% by volume or less.

JP 2010-108889 A Japanese Patent No. 4190930 International Publication No. WO2009 / 078159 Pamphlet JP 2006-286531 A JP 2007-188777 A International Publication No. WO2009 / 044741 Pamphlet

  In recent years, electronic devices, etc. to which secondary batteries are applied have become increasingly sophisticated and multifunctional, and the frequency of use of such electronic devices has increased, so further improvements have been demanded in the battery characteristics of secondary batteries. Yes.

  The present technology has been made in view of such problems, and an object thereof is to provide a secondary battery, a battery pack, an electric vehicle, an electric power storage system, an electric tool, and an electronic device that can obtain excellent battery characteristics. There is.

  The secondary battery of this technique is equipped with electrolyte solution with the positive electrode and negative electrode which were opposed through the separator. The positive electrode includes a lithium-containing compound. The lithium-containing compound includes at least one of the compound represented by the following formula (1) and the compound represented by the formula (2), and the average primary particle size of the lithium-containing compound is 0.05 μm to 1 μm. It is. The separator includes a porous base material layer and a polymer compound layer. The polymer compound layer is formed by applying a polymer material in which inorganic oxide particles are dispersed and applied to at least one of a surface facing the positive electrode and a surface facing the negative electrode of the base material layer. The average primary particle size of the inorganic oxide is 0.01 μm to 5 μm.

LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)

Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.)

  Moreover, the battery pack, the electric vehicle, the power storage system, the electric tool, or the electronic device of the present technology includes the above-described secondary battery.

  Here, the “average primary particle diameter” of the lithium-containing compound is an average particle diameter of so-called primary particles, and is calculated by the following procedure using a scanning electron microscope (SEM). First, a particulate (primary particle) lithium-containing compound is observed, and the particle size (major axis) of the primary particle is measured. The observation magnification at the time of measurement may be arbitrary as long as the outer edge (outline) of each primary particle can be specified and the boundary between the primary particles can be identified. Subsequently, the above-described particle size measurement operation is repeated for a plurality of primary particles. The number of measurement operations (number n) is preferably 300 or more from a statistical viewpoint. Finally, an average value of a plurality of measured values is calculated, and the average value is defined as an average primary particle size. The procedure for calculating the “average primary particle size” of the inorganic oxide is the same as the procedure for calculating the average primary particle size of the lithium-containing compound described above.

  In addition, “coating” means that in the polymer compound layer forming process, the forming material (polymer material and inorganic oxide) of the polymer compound layer is dispersed or dissolved in an organic solvent, and then the solution is dissolved. It means that it is applied to the surface of the base material layer and then dried. However, after the base material layer is immersed in the solution, the base material layer may be dried after being pulled up from the solution.

  According to the secondary battery of the present technology, the positive electrode includes the lithium-containing compound having the above-described composition and average primary particle size. In addition, the separator includes a porous base material layer and a polymer compound layer formed on the base material layer, and the polymer compound layer is an inorganic oxide having the above-described average primary particle size. Of the polymer material in which the particles are dispersed. Therefore, excellent battery characteristics can be obtained. Moreover, the same effect can be acquired also in the battery pack using the secondary battery of this technique, an electric vehicle, an electric power storage system, an electric tool, and an electronic device.

It is a perspective view showing the composition of the rechargeable battery of one embodiment of this art. It is sectional drawing along the II-II line of the winding electrode body shown in FIG. It is sectional drawing which expands and represents a part of winding electrode body shown in FIG. It is a block diagram showing the structure of the application example (battery pack) 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.

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

1. Secondary battery 1-1. Lithium ion secondary battery 1-2. Lithium metal secondary battery 2. Use of secondary battery 2-1. Battery pack 2-2. Electric vehicle 2-3. Electric power storage system 2-4. Electric tool

<1. Secondary battery>
<1-1. Lithium ion secondary battery>
FIG. 1 illustrates an exploded perspective configuration of a secondary battery according to an embodiment of the present technology. 2 shows a cross section taken along line II-II of the spirally wound electrode body 10 shown in FIG. 1, and FIG. 3 is an enlarged view of a part of the spirally wound electrode body 10 shown in FIG. .

[Overall structure of secondary battery]
The secondary battery described here is a lithium secondary battery (lithium ion secondary battery) in which the capacity of the negative electrode 14 can be obtained by occlusion and release of Li (lithium ion) as an electrode reactant.

  For example, as shown in FIG. 1, the secondary battery is a so-called laminate film type, and a wound electrode body 10 is housed inside a film-shaped exterior member 20. For example, as shown in FIGS. 2 and 3, the wound electrode body 10 is wound after the positive electrode 13 and the negative electrode 14 are stacked (opposed) via the separator 15 and the electrolyte layer 16. . In this wound electrode body 10, the positive electrode lead 11 is attached to the positive electrode 13 and the negative electrode lead 12 is attached to the negative electrode 14. The outermost peripheral part of the wound electrode body 10 is protected by a protective tape 17.

  For example, the positive electrode lead 11 and the negative electrode lead 12 are led out in the same direction from the inside of the exterior member 20 toward the outside. The positive electrode lead 11 is made of, for example, a conductive material such as aluminum, and the negative electrode lead 12 is made of, for example, a conductive material such as copper, nickel, or stainless steel. These conductive materials have, for example, a thin plate shape or a mesh shape.

  The exterior member 20 is a laminated film in which, for example, a fusion layer, a metal layer, and a surface protective layer are laminated in this order. In this laminated film, for example, the outer peripheral edges of the fusion layers of the two films are fused so that the fusion layer faces the wound electrode body 10. However, the two films may be bonded with an adhesive or the like. The fusing layer is, for example, a film of polyethylene or polypropylene. The metal layer is, for example, an aluminum foil. The surface protective layer is, for example, a film such as nylon or polyethylene terephthalate.

  Especially, it is preferable that the exterior member 20 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 20 may be a laminate film having another laminated structure, a polymer film such as polypropylene, or a metal film.

  An adhesive film 21 is inserted between the exterior member 20 and the positive electrode lead 11 and the negative electrode lead 12 in order to prevent intrusion of outside air. The adhesion film 21 is formed of a material having adhesion to the positive electrode lead 11 and the negative electrode lead 12. This adhesive material is, for example, a polyolefin resin such as polyethylene, polypropylene, modified polyethylene, or modified polypropylene.

[Positive electrode]
The positive electrode 13 has a positive electrode active material layer 13B on one surface or both surfaces of a positive electrode current collector 13A. 2 and 3 show the case where the positive electrode active material layer 13B is provided on both surfaces of the positive electrode current collector 13A.

  The positive electrode current collector 13A is formed of a conductive material such as aluminum, nickel, or stainless steel, for example.

  The positive electrode active material layer 13B includes one or more positive electrode materials capable of occluding and releasing lithium ions as a positive electrode active material, and a positive electrode binder, a positive electrode conductive agent, or the like as necessary. Other materials may be included.

  The positive electrode material is preferably a lithium-containing compound, and more specifically, preferably a lithium transition metal composite oxide or a lithium transition metal phosphate compound. This is because a high battery capacity can be obtained because the energy density is improved. The lithium transition metal composite oxide is an oxide containing Li and one or more transition metal elements as constituent elements, and the lithium transition metal phosphate compound is composed of Li and one or more transition metal elements. Is a phosphoric acid compound containing as a constituent element.

  The lithium-containing compound includes one or both of a compound represented by the following formula (1) and a compound represented by the formula (2). This is because, unlike lithium-containing compounds having other chemical structures, excellent battery characteristics can be obtained by satisfying the condition of the average primary particle diameter described later.

LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)

Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.)

The lithium-containing compound represented by the formula (1) is a lithium transition metal phosphate compound containing Li and a transition metal element (M1) as constituent elements, and has a so-called olivine type crystal structure. The type of M1 is not particularly limited as long as it is any one or more of Fe, Mn, and Co. Specific examples of the lithium transition metal phosphate compound include LiFePO ₄ , LiMnPO ₄ , LiCoPO _{4, and} LiFe _0.5 Mn _0.5 PO ₄ , and other compounds may be used.

The lithium-containing compound represented by the formula (2) is a lithium transition metal composite oxide containing Li, a transition metal element (Mn, Ni, and Co) and another element (M2) as constituent elements, and is a so-called layered rock salt type. It has a crystal structure of This lithium transition metal composite oxide is so-called lithium rich, as is apparent from the range of values that a can take. As is apparent from the range of values that b to d can take, Mn and Ni are essential constituent elements, but Co is not an essential constituent element. For this reason, lithium-containing compounds always contain Mn and Ni as constituent elements, but may or may not contain Co and M2 as constituent elements. The type of M2 is not particularly limited as long as it is any one or two or more of Mg, Al, Zn, Ti and V. Specific examples of this lithium transition metal composite oxide include Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 Al _0.01 O ₂ , Li _1.13 (Mn _0.5 Ni _0.2 Co _0.3 ) _0.87 Al _0.01 O ₂ , Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 Mg _0.01 O ₂ , Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 Zn _0.01 O ₂ , Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 Ti _0.01 O ₂ or Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 V _0.01 O ₂ etc., and other compounds may be used.

The above-mentioned “lithium-containing compound having another chemical structure” is, for example, a lithium-containing compound that does not have the chemical structure shown in Formula (1) and Formula (2). Specifically, for example, a lithium-containing compound having a spinel-type crystal structure, or a lithium-containing compound having a layered rock salt-type crystal structure but not lithium-rich is used. Specific examples of the former lithium-containing compound are LiMn ₂ O _{4 and the} like, and specific examples of the latter lithium-containing compound are LiCoO ₂ , LiNiO _{2, and} LiNi _0.5 Co _0.2 Mn _0.3 O ₂ .

  The average particle size (average primary particle size) of primary particles of this lithium-containing compound is fine compared to the average primary particle size of general lithium-containing compounds, specifically about 0.05 μm to 1 μm. is there. This is because the average primary particle size of the lithium-containing compound is optimized, so that excellent battery characteristics can be obtained. Specifically, when the average primary particle diameter is smaller than 0.05 μm, the reactivity of the lithium-containing compound is increased due to the increase in the surface area, so that the cycle characteristics are deteriorated and the secondary battery is easily swelled. On the other hand, when the average primary particle size is larger than 1 μm, the reaction rate of lithium is remarkably lowered, so that load characteristics are lowered. As described above, the “average primary particle size” of the lithium-containing compound is a particle of primary particles calculated based on observation results (measurement results of a plurality of particle sizes) using a scanning electron microscope (SEM). It is an average value of the diameter (major axis). The number of measurements for calculating the average value is preferably 300 or more, and is 300 here.

  In addition, as long as the positive electrode active material layer 13B contains the lithium containing compound mentioned above as a positive electrode active material, it may contain the other kind of lithium containing compound as needed. Such other lithium-containing compounds are, for example, lithium-containing compounds having the above-mentioned spinel-type crystal structure, or lithium-containing compounds having a layered rock salt-type crystal structure but not lithium-rich. Other types of lithium-containing compounds may be, for example, oxides, disulfides, chalcogenides, or conductive polymers. 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 is, for example, any one kind or two kinds or more of synthetic rubber or polymer material. Examples of the synthetic rubber include styrene butadiene rubber, fluorine rubber, and ethylene propylene diene. The polymer material is, for example, polyvinylidene fluoride or polyimide.

  The positive electrode conductive agent is, for example, any one type or two or more types of carbon materials. Examples of the carbon material include graphite, carbon black, acetylene black, and ketjen black. The positive electrode conductive agent may be a metal material or a conductive polymer as long as it is a conductive material.

[Negative electrode]
The negative electrode 14 has a negative electrode active material layer 14B on one surface or both surfaces of a negative electrode current collector 14A. 2 and 3 show the case where the negative electrode active material layer 14B is provided on both surfaces of the negative electrode current collector 14A.

  The negative electrode current collector 14A is formed of a conductive material such as copper, nickel, or stainless steel, for example. The surface of the negative electrode current collector 14A is preferably roughened. This is because the so-called anchor effect improves the adhesion of the negative electrode active material layer 14B to the negative electrode current collector 14A. In this case, the surface of the negative electrode current collector 14A only needs to be roughened at least in a region facing the negative electrode active material layer 14B. The roughening method is, for example, a method of forming fine particles using electrolytic treatment. This electrolytic treatment is a method of providing irregularities by forming fine particles on the surface of the negative electrode current collector 14A using an electrolytic 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 14B includes any one or more of negative electrode materials capable of occluding and releasing lithium ions as a negative electrode active material, and a negative electrode binder or a negative electrode conductive agent, as necessary. Other materials may be included. Details regarding the negative electrode binder and the negative electrode conductive agent are the same as, for example, 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 13 in order to prevent unintentional deposition of lithium metal on the negative electrode 14 during charging. That is, it is preferable that the electrochemical equivalent of the negative electrode material capable of occluding and releasing lithium ions is larger than the electrochemical equivalent of the positive electrode 13.

  The negative electrode material is, for example, a carbon material. This is because the change in crystal structure at the time of occlusion and release of lithium ions is very small, so that high energy density and excellent cycle characteristics can be obtained. Moreover, it is because a carbon material functions also as a negative electrode electrically conductive agent. Examples of the carbon material include graphitizable carbon, non-graphitizable carbon having a (002) plane spacing of about 0.37 nm or more, or graphite having a (002) plane spacing of about 0.34 nm or less. It is. More specifically, pyrolytic carbons, cokes, glassy carbon fibers, organic polymer compound fired bodies, activated carbon or 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 or a furan resin at an appropriate temperature. In addition, the carbon material may be low crystalline carbon or amorphous carbon that has been heat-treated at a temperature of about 1000 ° C. or less. 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 material) containing any one or two of a metal element and a metalloid element as a constituent element. This is because a high energy density can be obtained. The metal-based material may be a simple substance, an alloy or a compound, or two or more of them, or one having at least a part of one or more of those phases. 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 includes a solid solution, a eutectic (eutectic mixture), an intermetallic compound, or a coexistence of two or more kinds thereof.

  The metal element or metalloid element described above is, for example, one or more metal elements or metalloid elements capable of forming an alloy with Li. Specifically, for example, Mg, B, Al, Ga, In, Si, Ge, Sn, Pb, Bi, Cd, Ag, Zn, Hf, Zr, Y, Pd, or Pt. Among these, at least one of Si and Sn is preferable. This is because the ability to occlude and release lithium ions is excellent, and a high energy density can be obtained.

  The material containing at least one of Si and Sn as a constituent element may be a simple substance, an alloy, or a compound of Si or Sn, or two or more of them, or at least one or two or more phases thereof. You may have in part. The simple substance is a simple substance in a general sense (may contain a small amount of impurities), and does not necessarily mean 100% purity.

  The alloy of Si is, for example, any one or two of Sn, Ni, Cu, Fe, Co, Mn, Zn, In, Ag, Ti, Ge, Bi, Sb or Cr as constituent elements other than Si. It contains the above elements. The compound of Si includes, for example, any one kind or two kinds or more such as C or O as a constituent element other than Si. Note that the Si compound may include, for example, one or more of the elements described for the Si alloy as a constituent element other than Si.

Examples of the Si alloy or compound include 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), LiSiO, or the like. Note that _v in SiO _v may be 0.2 <v <1.4.

The alloy of Sn is, for example, any one of elements such as Si, Ni, Cu, Fe, Co, Mn, Zn, In, Ag, Ti, Ge, Bi, Sb or Cr as a constituent element other than Sn or Includes two or more. The Sn compound contains, for example, any one or more constituent elements such as C or O as constituent elements other than Sn. The Sn compound may contain, for example, one or more of the elements described for the Sn alloy as a constituent element other than Sn. Examples of the alloy or compound of Sn include SnO _w (0 <w ≦ 2), SnSiO ₃ , LiSnO, and Mg ₂ Sn.

  Moreover, it is preferable that the material containing Sn is, for example, a material containing Sn as the first constituent element and additionally containing the second and third constituent elements. The second constituent element is, for example, Co, Fe, Mg, Ti, V, Cr, Mn, Ni, Cu, Zn, Ga, Zr, Nb, Mo, Ag, In, Ce, Hf, Ta, W, Bi or Any one or more of Si and the like. The third constituent element is, for example, any one type or two or more types such as B, C, Al, and P. This is because high battery capacity and excellent cycle characteristics can be obtained by including the second and third constituent elements.

  Among these, a material containing Sn, Co, and C as constituent elements (SnCoC-containing material) is preferable. As the composition of the SnCoC-containing material, for example, the C content is 9.9 mass% to 29.7 mass%, and the Sn and Co content ratio (Co / (Sn + Co)) is 20 mass% to 70 mass%. It is. This is because a high energy density can be obtained.

  This SnCoC-containing material has a phase containing Sn, Co, and C, and the phase is preferably low crystalline or amorphous. This phase is a reaction phase capable of reacting with Li, and excellent characteristics can be obtained due to the presence of the reaction phase. The half width of the diffraction peak obtained by X-ray diffraction of this phase is preferably 1 ° or more at a diffraction angle 2θ when CuKα ray is used as the specific X-ray and the drawing speed is 1 ° / min. This is because lithium ions are occluded and released more smoothly and the reactivity to the electrolyte is reduced. Note that 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 a diffraction peak obtained by X-ray diffraction corresponds to a reaction phase capable of reacting with Li can be easily determined by comparing X-ray diffraction charts before and after electrochemical reaction with Li. . For example, if the position of the diffraction peak changes before and after the electrochemical reaction with Li, it corresponds to a reaction phase capable of reacting with Li. 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 has, for example, each of the above-described constituent elements, and is considered to be low crystallization or amorphous mainly due to the presence of C.

  In the SnCoC-containing material, it is preferable that at least a part of C 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 Sn or the like is suppressed. The bonding state of elements can be confirmed by, 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 C is bonded to a metal element, a metalloid element, or the like, the peak of the synthesized wave of C 1s orbital (C1s) appears in a region lower than 284.5 eV. It is assumed that energy calibration is performed so that a peak of 4f orbit (Au4f) of Au atoms is obtained at 84.0 eV. At this time, since the surface contamination carbon usually exists on the surface of the substance, the C1s peak of the surface contamination carbon is set to 284.8 eV, which is used as the energy standard. In XPS measurement, the waveform of the C1s peak is obtained in a form that includes the surface contamination carbon peak and the carbon peak in the SnCoC-containing material. Isolate. 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).

  The SnCoC-containing material is not limited to a material (SnCoC) whose constituent elements are only Sn, Co, and C. That is, for example, the SnCoC-containing material may be any one or more of Si, Fe, Ni, Cr, In, Nb, Ge, Ti, Mo, Al, P, Ga, Bi, etc., if necessary. May be included as a constituent element.

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

  In addition, the negative electrode material may be, for example, a metal oxide or a polymer compound. Examples of the metal oxide include iron oxide, ruthenium oxide, and molybdenum oxide. Examples of the polymer compound include polyacetylene, polyaniline, and polypyrrole.

  The negative electrode active material layer 14B is formed by, for example, a coating method, a gas phase method, a liquid phase method, a thermal spraying method, a firing method (sintering method), or two or more kinds thereof. The coating method is, for example, a method in which a negative electrode active material in the form of particles (powder) is mixed with a negative electrode binder or the like and then dispersed in a solvent such as an organic solvent before being applied to the negative electrode current collector 14A. The vapor phase method is, for example, a physical deposition method or 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, or a plasma chemical vapor deposition method. The liquid phase method is, for example, an electrolytic plating method or 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 14A. The firing method is, for example, a method of applying a heat treatment at a temperature higher than the melting point of the negative electrode binder or the like after being applied to the negative electrode current collector 14A using a coating method. As the firing method, for example, a known method such as an atmosphere firing method, a reaction firing method, or a hot press firing method can be used.

  In this secondary battery, as described above, in order to prevent unintentional deposition of lithium metal on the negative electrode 14 during charging, the electrochemical equivalent of the negative electrode material capable of occluding and releasing lithium ions is It is preferably larger than the electrochemical equivalent. In addition, when the open circuit voltage (that is, the battery voltage) at the time of full charge is 4.25 V or more, lithium ions are released per unit mass even when the same positive electrode active material is used as compared with the case of 4.2 V. Since the amount increases, the amounts of the positive electrode active material and the negative electrode active material are adjusted accordingly. Thereby, a high energy density can be obtained.

[Separator]
The separator 15 separates the positive electrode 13 and the negative electrode 14 and allows lithium ions to pass through while preventing a short circuit of current due to contact between the two electrodes. As shown in FIG. 3, the separator 15 includes a porous base material layer 15A and a polymer compound layer 15B applied and formed on one or both surfaces of the base material layer 15A. This is because the adhesion of the separator 15 to the positive electrode 13 and the negative electrode 14 is improved, so that the distortion of the wound electrode body 10 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 15A is also suppressed. Therefore, the resistance is not easily increased even after repeated charging and discharging, and the secondary battery Becomes difficult to swell.

  The above-mentioned “single side” is one of the surface of the base material layer 15 </ b> A facing the positive electrode 13 or the surface facing the negative electrode 14, and “both surfaces” is the surface facing the positive electrode 13. , And the surface facing the negative electrode 14. FIG. 3 shows a case where the polymer compound layer 15B is provided on both surfaces of the base material layer 15A.

  The base material layer 15A 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. Although the kind of synthetic resin is not specifically limited, For example, it is any 1 type or 2 types or more of polymeric materials, such as polyolefin. The polyolefin is, for example, polyethylene, polypropylene or polytetrafluoroethylene, and may be other polymer material.

  The polymer compound layer 15B is applied and formed on the surface of the base material layer 15A as described above. In the forming step of the polymer compound layer 15B, the porous material layer 15A is impregnated with the material for forming the polymer compound layer 15B in a dissolved state or dispersed state (a polymer material described later). This is because the adhesion of the polymer compound layer 15B is improved. As described above, this “coating formation” means that after the material for forming the polymer compound layer 15B (polymer material and inorganic oxide described later) is dispersed or dissolved in an organic solvent or the like, the solution is the base material layer. It means that it is applied to the surface of 15A and then dried. However, after the base material layer 15A is immersed in the solution, the base material layer 15A may be dried after being pulled up from the solution.

  The polymer compound layer 15B includes a polymer material in which inorganic oxide particles are dispersed. This is because the cycle characteristics, battery swelling characteristics, and the like are further improved as compared with the case where the inorganic oxide particles are not dispersed.

  The type of the polymer material is not particularly limited, but among them, one or more of polyvinylidene fluoride, polyvinyl formal, polyacrylic acid ester, methyl methacrylate, and the like are preferable. This is because it has excellent physical strength and is electrochemically stable. However, the polymer material may be a material other than the above.

  The kind of the inorganic oxide is not particularly limited, but among them, it is preferable that any one kind or two kinds or more of aluminum oxide, silicon oxide, titanium oxide, and the like be used. This is because a higher effect can be obtained. In order to form the polymer compound layer 15B including the inorganic oxide particles, for example, the inorganic oxide particles may be dispersed in the above-described coating or dipping solution. The content of the inorganic oxide in the polymer compound layer 15B may be arbitrary.

  The average particle size (average primary particle size) of primary particles of the inorganic oxide is about 0.01 μm to 5 μm. This is because the battery swelling characteristics are further improved as compared with the case where the average primary particle diameter is out of the range. The “average primary particle size” of the inorganic oxide is the average particle size of so-called primary particles, and the measurement procedure is the same as the measurement procedure of the average primary particle size of the lithium-containing compound described above.

[Electrolyte layer]
The electrolyte layer 16 is a so-called gel electrolyte in which an electrolytic solution is held by a polymer compound. 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 16 may include other materials such as additives as necessary.

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

  The electrolytic solution contains a solvent and an electrolyte salt, and may contain other materials such as additives as necessary.

  The solvent contains one or more of nonaqueous solvents such as organic solvents. This non-aqueous solvent is, for example, a cyclic carbonate, a chain carbonate, a lactone, a chain carboxylic acid ester, or a nitrile. This is because excellent battery capacity, cycle characteristics, storage characteristics, and the like can be obtained. The cyclic carbonate is, for example, ethylene carbonate, propylene carbonate, or butylene carbonate, and the chain carbonate is, for example, dimethyl carbonate, diethyl carbonate, ethyl methyl carbonate, or methyl propyl carbonate. The lactone is, for example, γ-butyrolactone or 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 the nitrile include acetonitrile, glutaronitrile, adiponitrile, methoxyacetonitrile, and 3-methoxypropionitrile.

  In addition, examples of the non-aqueous 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, or dimethyl sulfoxide. This is because similar advantages can be obtained.

  Among these, at least one 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, a high viscosity (high dielectric constant) solvent such as ethylene carbonate or propylene carbonate (for example, a relative dielectric constant ε ≧ 30) and a low viscosity solvent such as dimethyl carbonate, ethyl methyl carbonate or 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 preferably contains any one or more of unsaturated cyclic carbonates. This is because a stable protective film is formed mainly on the surface of the negative electrode 14 during charge and discharge, and thus the decomposition reaction of the electrolytic solution is suppressed. This unsaturated cyclic carbonate is a cyclic carbonate having one or more unsaturated carbon bonds (carbon-carbon double bonds). Specific examples of the unsaturated cyclic carbonate include vinylene carbonate, vinyl ethylene carbonate, methylene ethylene carbonate, and the like, and other compounds may be used. Although content of unsaturated cyclic carbonate in a solvent is not specifically limited, For example, they are 0.01 weight%-10 weight%.

  Moreover, it is preferable that the solvent contains any 1 type or 2 types or more of halogenated carbonates. This is because a stable protective film is formed mainly on the surface of the negative electrode 14 during charge and discharge, and thus the decomposition reaction of the electrolytic solution is suppressed. This 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 chain halogenated carbonates include fluoromethyl methyl carbonate, bis (fluoromethyl) carbonate, and difluoromethyl methyl carbonate. However, specific examples of the halogenated carbonate may be compounds other than those described above. Although content of halogenated carbonate in a solvent is not specifically limited, For example, they are 0.01 weight%-50 weight%.

  Moreover, it is preferable that the solvent contains sultone (cyclic sulfonate ester). This is because the chemical stability of the electrolytic solution is further improved. This sultone is, for example, propane sultone or propene sultone, and other compounds may be used. Although content of sultone in a solvent is not specifically limited, For example, it is 0.5 weight%-5 weight%.

  Furthermore, it is preferable that the solvent contains an acid anhydride. This is because the chemical stability of the electrolytic solution is further improved. Examples of the acid anhydride include a carboxylic acid anhydride, a disulfonic acid anhydride, and a carboxylic acid sulfonic acid anhydride. Examples of the carboxylic acid anhydride include succinic anhydride, glutaric anhydride, and maleic anhydride. Examples of the disulfonic anhydride include ethanedisulfonic anhydride and propanedisulfonic anhydride. Examples of the carboxylic acid sulfonic acid anhydride include anhydrous sulfobenzoic acid, anhydrous sulfopropionic acid, and anhydrous sulfobutyric acid. However, specific examples of the acid anhydride may be compounds other than those described above. Although content of the acid anhydride in a solvent is not specifically limited, For example, they are 0.5 weight%-5 weight%.

  Here, in the electrolyte layer 16 which is a gel electrolyte, the solvent of the electrolytic solution is a wide concept including not only a liquid solvent 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.

  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, for example, a salt other than the lithium salt (for example, a light metal salt other than the lithium salt).

This lithium salt includes, for example, lithium hexafluorophosphate (LiPF ₆ ), lithium tetrafluoroborate (LiBF ₄ ), lithium perchlorate (LiClO ₄ ), lithium hexafluoroarsenate (LiAsF ₆ ), tetra Lithium phenylborate (LiB (C ₆ H ₅ ) ₄ ), lithium methanesulfonate (LiCH ₃ SO ₃ ), lithium trifluoromethanesulfonate (LiCF ₃ SO ₃ ), lithium tetrachloroaluminate (LiAlCl ₄ ), hexafluoride Dilithium silicate (Li ₂ SiF ₆ ), lithium chloride (LiCl), or lithium bromide (LiBr), and other compounds may be used. This is because excellent battery capacity, cycle characteristics, storage characteristics, and the like can be obtained.

Among these, at least one of LiPF ₆ , LiBF ₄ , LiClO ₄ and LiAsF ₆ is preferable, and LiPF ₆ is more preferable. This is because a higher effect can be obtained because the internal resistance is lowered.

  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.

  In place of the gel electrolyte layer 16, an electrolytic solution may be used as it is. In this case, the electrolytic solution is impregnated in the separator 15.

[Operation of secondary battery]
In this secondary battery, for example, at the time of charging, lithium ions released from the positive electrode 13 are occluded by the negative electrode 14 via the electrolyte layer 16, and at the time of discharging, lithium ions released from the negative electrode 14 are absorbed by the electrolyte layer. 16 is occluded in the positive electrode 13 through the electrode 16.

[Method for producing secondary battery]
The secondary battery including the gel electrolyte layer 16 is manufactured by, for example, the following three types of procedures.

  In the first procedure, first, the positive electrode 13 is manufactured. A positive electrode active material containing a lithium-containing compound having the above composition and average primary particle size is mixed with a positive electrode binder, a positive electrode conductive agent, and the like as necessary 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, the positive electrode mixture slurry is applied to both surfaces of the positive electrode current collector 13A and then dried to form the positive electrode active material layer 13B. Subsequently, the positive electrode active material layer 13B is compression-molded using a roll press machine or the like while being heated as necessary. In this case, compression molding may be repeated a plurality of times.

  In addition, the negative electrode 14 is produced by the same procedure as that of the positive electrode 13 described above. A negative electrode mixture in which a negative electrode active material and, if necessary, a negative electrode binder and a negative electrode conductive agent are mixed is dispersed in an organic solvent or the like to obtain a paste-like negative electrode mixture slurry. Subsequently, the negative electrode mixture slurry is applied to both surfaces of the negative electrode current collector 14A and dried to form the negative electrode active material layer 14B, and then the negative electrode active material layer 14B is compression molded as necessary.

  Further, the separator 15 is formed. After the polymer material is dissolved in an organic solvent or the like, inorganic oxide particles are dispersed in the solution to obtain a paste-like polymer slurry. Subsequently, a polymer slurry is applied to both surfaces of the base material layer 15A and then dried to form a polymer compound layer 15B including a polymer material in which inorganic oxide particles are dispersed.

  Moreover, after preparing the precursor solution containing electrolyte solution, a high molecular compound, an organic solvent, etc., the precursor solution is apply | coated to the positive electrode 13 and the negative electrode 14, and the gel electrolyte layer 16 is formed. Subsequently, the positive electrode lead 11 is attached to the positive electrode current collector 13A using a welding method or the like, and the negative electrode lead 12 is similarly attached to the negative electrode current collector 14A using a welding method or the like. Subsequently, after the positive electrode 13 and the negative electrode 14 are laminated via the separator 15 and wound to produce the wound electrode body 10, the protective tape 17 is attached to the outermost periphery. Subsequently, after sandwiching the wound electrode body 10 between the two film-shaped exterior members 20, the outer peripheral edge portions of the exterior member 20 are bonded to each other using a heat fusion method or the like. The spirally wound electrode body 10 is sealed inside. In this case, the adhesion film 21 is inserted between the positive electrode lead 11 and the negative electrode lead 12 and the exterior member 20.

  In the second procedure, the positive electrode lead 11 is attached to the positive electrode 13 and the negative electrode lead 12 is attached to the negative electrode 14. Subsequently, the positive electrode 13 and the negative electrode 14 are stacked via the separator 15 and wound to produce a wound body that is a precursor of the wound electrode body 10, and then a protective tape 17 is attached to the outermost peripheral portion thereof. paste. Subsequently, after sandwiching the wound body between the two film-shaped exterior members 20, the remaining outer peripheral edge except for the outer peripheral edge on one side is bonded using a thermal fusion method or the like, and the bag The wound body is housed inside the shaped exterior member 20. Subsequently, an electrolyte composition containing an 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 is prepared to form a bag-shaped exterior member. After injecting into the inside of the exterior member 20, the exterior member 20 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 16 is formed.

  In the third procedure, a wound body is produced and stored in the bag-shaped exterior member 20 in the same manner as in the second procedure described above except that the separator 15 coated with the polymer compound on both sides is used. The polymer compound applied to the separator 15 is, for example, a polymer (homopolymer, copolymer or multi-component copolymer) containing vinylidene fluoride as a component. Specifically, a binary copolymer comprising polyvinylidene fluoride, vinylidene fluoride and hexafluoropropylene as components, or a ternary copolymer comprising vinylidene fluoride, hexafluoropropylene and chlorotrifluoroethylene as components. Etc. In addition to the polymer containing vinylidene fluoride as a component, one or more other polymer compounds may be used. Then, after preparing electrolyte solution and inject | pouring inside the exterior member 20, the opening part of the exterior member 20 is sealed using a heat sealing | fusion method etc. FIG. Subsequently, the exterior member 20 is heated while applying a load, and the separator 15 is brought into close contact with the positive electrode 13 and the negative electrode 14 through the polymer compound. Thereby, since the electrolytic solution is impregnated into the polymer compound, the polymer compound is gelled to form the electrolyte layer 16.

[Operation and effect of secondary battery]
According to this lithium ion secondary battery, the positive electrode 13 includes a lithium-containing compound having the above-described composition and average primary particle size. The separator 15 includes a porous base material layer 15A and a polymer compound layer 15B applied and formed on the base material layer 15A. The polymer compound layer 15B has the above-described average primary particle diameter. A polymer material in which particles of an inorganic oxide having s are dispersed. In this case, as described above, the composition and average primary particle size of the lithium-containing compound are optimized, and the average primary particle size of the inorganic oxide is optimized, so that a high energy density is obtained, Cycle characteristics and load characteristics are improved. In addition, since the adhesion of the polymer compound layer 15B to the base material layer 15A is improved, the cycle characteristics and the like are further improved, and the secondary battery is not easily swollen even after repeated charge and discharge. Therefore, excellent battery characteristics can be obtained.

  In particular, when the polymer material of the polymer compound layer 15B is polyvinylidene fluoride or the like, or the inorganic oxide is aluminum oxide or the like, higher effects can be obtained.

  In the laminated film type secondary battery in which the positive electrode 13, the negative electrode 14, the separator 15, and the electrolytic solution are housed in the film-shaped exterior member 20, the positive electrode 13, the negative electrode 14, the separator 15, and the separator 15 As a result, battery swelling tends to be more apparent. Therefore, in the viewpoint of improving the battery swell characteristic, a higher effect can be obtained with a laminate film type secondary battery.

<1-2. Lithium metal secondary battery>
The secondary battery described here is a lithium secondary battery (lithium metal secondary battery) in which the capacity of the negative electrode is expressed by precipitation and dissolution of lithium metal. This secondary battery has the same configuration as the above-described lithium ion secondary battery except that the negative electrode active material layer 14B is made of lithium metal, and is manufactured by the same procedure. However, the separator 15 is impregnated with an electrolytic solution that is a liquid electrolyte.

  Since this secondary battery uses lithium metal as the negative electrode active material, a high energy density can be obtained. The negative electrode active material layer 14 </ b> B may already exist from the time of assembly, but may not be present at the time of assembly and may be composed of lithium metal deposited during charging. Further, the negative electrode current collector 14A may be omitted by using the negative electrode active material layer 14B as a current collector.

  In this secondary battery, for example, at the time of charging, lithium ions are released from the positive electrode 13 and deposited as lithium metal on the surface of the negative electrode current collector 14A through the electrolytic solution. Further, for example, during discharge, lithium metal elutes as lithium ions from the negative electrode active material layer 14B and is occluded in the positive electrode 13 through the electrolytic solution.

  According to this lithium metal secondary battery, since the positive electrode 13 and the separator 15 have the same configuration as the above-described lithium ion secondary battery, excellent battery characteristics are obtained for the same reason as the lithium ion secondary battery. Can be obtained. Other operations and effects are the same as those of the lithium ion secondary battery.

<2. Applications of secondary batteries>
Next, application examples of the above-described secondary battery will be described.

  The secondary battery can be used for a machine, device, instrument, device or system (an assembly 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. Note that 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 or switched from the main power source). When a secondary battery is used as an auxiliary power source, the type of main power source is not limited to a 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. A storage device such as a backup power supply or a memory card. An electric tool such as an electric drill or an electric saw. It is a battery pack used for a notebook computer or the like as a detachable power source. A medical electronic device such as a pacemaker or hearing aid. 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.

  Among them, it is effective that the secondary battery is applied to a battery pack, an electric vehicle, an electric power storage system, an electric tool, an electronic device, or 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 that is a power storage source, and the power is consumed as necessary, so that household electrical products can be used. 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, it can change suitably.

<2-1. Battery Pack>
FIG. 4 shows a block configuration of the battery pack. This 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 inside a housing 60 formed of a plastic material or the like. 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 central processing unit (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 (AD), and supplies the converted voltage to the controller 61.

  The switch control unit 67 controls the operation of the switch unit 63 according to signals input from the current measurement unit 64 and the voltage measurement 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. The switch control unit 67 is configured to cut off the charging current when a large current flows during charging, for example.

  Further, the switch control unit 67 controls the switch unit 63 (discharge control switch) to be disconnected so that the discharge current does not flow through the current path of the power source 62 when the battery voltage reaches the overdischarge detection voltage, for example. To do. As a result, the power source 62 can only be charged via the charging diode. For example, the switch control unit 67 is configured to cut off the discharge current when a large current flows during discharging.

  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 and information (for example, internal resistance in an initial state) of the secondary battery measured in the manufacturing process stage. If the full charge capacity of the secondary battery is stored in the memory 68, the control unit 10 can grasp information such as the remaining capacity.

  The temperature detection element 69 measures the temperature of the power supply 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 (eg, a notebook personal computer) that is operated using a battery pack or an external device (eg, a charger) that is used to charge the battery pack. Terminal. Charging / discharging of the power source 62 is performed via the positive terminal 71 and the negative terminal 72.

<2-2. Electric vehicle>
FIG. 5 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 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 that is a driving unit, a transmission 80, and a clutch 81. The rotational force of the engine 75 is also transmitted to the generator 79. The generator 79 generates AC power by the rotational force, and the AC power is converted into DC power via the inverter 83 and stored in the power source 76. Is done. On the other hand, when the motor 77 serving as a 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 by 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 may be transmitted as a rotational force to the motor 77, and the motor 77 may generate AC power by the rotational force. 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 or 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.

  In the above description, the hybrid vehicle is described as the electric vehicle. However, 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.

<2-3. Power storage system>
FIG. 6 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 inside a house 89 such as a general house or a commercial building.

  Here, the power source 91 is connected to, for example, an electric device 94 installed inside 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 the smart meter 92 and the power hub 93. It has become.

  Note that the electric device 94 includes, for example, one or more home appliances, and the home appliances are, for example, a refrigerator, an air conditioner, a television, or a water heater. The private power generator 95 is, for example, one type or two or more types such as a solar power generator or a wind power generator. The electric vehicle 96 is, for example, one type or two or more types such as an electric vehicle, an electric motorcycle, or a hybrid vehicle. The centralized power system 97 is, for example, one type or two or more types such as a thermal power plant, a nuclear power plant, a hydroelectric power plant, or 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 controls the balance between supply and demand in the house 89 while communicating with the outside as necessary, thereby enabling efficient and stable energy supply.

  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 the power hub 93 is connected from the solar power generator 95 that is an independent power source. Power is accumulated in the power source 91 through the power source 91. The electric power stored in the power supply 91 is supplied to the electric device 94 or the electric vehicle 96 as required according to an instruction from the control unit 90, so that the electric device 94 can be operated and the electric vehicle 96 is operated. 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 amount of electricity used is low, and the power stored in the power source 91 is used during the day when the amount of electricity used 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).

<2-4. Electric tool>
FIG. 7 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). This controlled object 99 is moved by supplying electric power from the power supply 100 to the drill unit 101 as necessary in accordance with operation of an operation switch (not shown).

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

(Experimental Examples 1 to 43)
The laminate film type lithium ion secondary battery shown in FIGS. 1 to 3 was produced by the following procedure.

  When producing the positive electrode 13, first, lithium-containing compounds having the compositions and average primary particle diameters (μm) shown in Tables 1 to 3 were prepared by a synthesis procedure described later. The procedure for calculating the average primary particle size of this lithium-containing compound (n number = 300) is as described above. Subsequently, 90 parts by mass of the positive electrode active material (lithium-containing compound), 5 parts by mass of the positive electrode binder (polyvinylidene fluoride (PVDF)) and 5 parts by mass of the positive electrode conductive agent (graphite) were kneaded (kneading time = 1). Time) to obtain a positive electrode mixture. Subsequently, the positive electrode mixture was dispersed in an organic solvent (N-methyl-2-pyrrolidone (NMP)) to obtain a paste-like positive electrode mixture slurry. Subsequently, the positive electrode mixture slurry was uniformly applied on both surfaces of the positive electrode current collector 13A (20 μm thick aluminum foil) using a coating apparatus, and then dried to form the positive electrode active material layer 13B. Finally, the positive electrode current collector 13A on which the positive electrode active material layer 13B was formed was cut into a strip shape and then vacuum-dried (drying temperature = 100 ° C.).

  When producing the negative electrode 14, first, 97 parts by mass of a negative electrode active material (graphite) and 3 parts by mass of a negative electrode binder (PVDF) were mixed to obtain a negative electrode mixture. Subsequently, the negative electrode mixture was dispersed in an organic solvent (NMP) to obtain a paste-like negative electrode mixture slurry. Subsequently, the negative electrode mixture slurry was uniformly applied to both surfaces of the negative electrode current collector 14A (15 μm thick electrolytic copper foil) using a coating apparatus and then dried to form the negative electrode active material layer 14B. Finally, the negative electrode current collector 14A on which the negative electrode active material layer 14B was formed was cut into a strip shape and then vacuum-dried (drying temperature = 100 ° C.).

When preparing an electrolytic solution, an electrolyte salt (LiPF ₆ ) was dissolved in a solvent. This solvent is a mixed solvent in which ethylene carbonate (EC), ethylmethyl carbonate (EMC), and 4-fluoro-1,3-dioxolan-2-one (FEC) are mixed. In this case, the mixing ratio (mass ratio) of the solvent was EC: EMC: FEC = 39: 60: 1, and the mixing ratio (mass ratio) of the solvent and the electrolyte salt was solvent: electrolyte salt = 86: 14.

In the case of producing the separator 15, first, the polymer materials (average molecular weight = 150,000) shown in Tables 1 to 3 were dissolved in an organic solvent (NMP) to obtain a polymer slurry. The polymer material is polyvinylidene fluoride (PVDF), polyvinyl formal (PVF), polyacrylate (PMA), or methyl methacrylate (MM). In this case, the mixing ratio (mass ratio) was set to polymer material: organic solvent = 10: 90. In addition, the inorganic oxide particles having the average primary particle sizes shown in Tables 1 to 3 were dispersed in the polymer slurry as necessary. This inorganic oxide is aluminum oxide (Al ₂ O ₃ ), silicon oxide (SiO ₂ ), or titanium oxide (TiO ₂ ). In this case, the mixing ratio (mass ratio) was set to polymer material: inorganic oxide = 1: 2. The procedure for calculating the average primary particle diameter (μm) of this inorganic oxide (n number = 300) is as described above. Subsequently, a polymer slurry was applied to both surfaces of the base material layer 15A (9 μm thick porous polyethylene (PE)) using a desktop coater (application thickness = 2 μm). Finally, the coating film was phase-separated using a water bath, and then dried with hot air to form a porous polymer compound layer 15B (thickness = 4 μm). For comparison, the base material layer 15A was used in place of the separator 15 without forming the polymer compound layer 15B on both surfaces of the base material layer 15A. In addition, a polymer compound layer 15B in which inorganic oxide particles were not dispersed was formed on both surfaces of the base material layer 15A.

  When assembling the secondary battery, first, the positive electrode lead 11 made of aluminum was welded to one end of the positive electrode current collector 13A, and the negative electrode lead 12 made of nickel was welded to one end of the negative electrode current collector 14A. Subsequently, after the positive electrode 13, the separator 15, the negative electrode 14, and the separator 15 are laminated in this order and wound in the longitudinal direction, the winding end portion is fixed with a protective tape 17 (adhesive tape), A wound body that is a precursor of the wound electrode body 10 was formed. Subsequently, after the wound body was sandwiched between the exterior members 20, the outer edge portions except for one side were heat-sealed, and the wound body was housed inside the bag-shaped exterior member 20. The exterior member 20 is a three-layer laminate film in which a nylon film (thickness = 30 μm), an Al foil (thickness = 40 μm), and an unstretched polypropylene film (thickness = 30 μm) are laminated from the outside. (Total thickness = 100 μm). Finally, 2 g of electrolyte solution was injected from the opening of the exterior member 20 to impregnate the separator 15. Thereby, a laminated film type secondary battery was completed. In the case of manufacturing a secondary battery, the thickness of the positive electrode active material layer 13B was adjusted so that lithium metal did not deposit on the negative electrode 14 at the time of full charge.

Here, the synthesis procedure of the lithium-containing compound used to produce the positive electrode 13 is as follows. When the positive electrode 13 was produced, LiNi _0.5 Co _0.2 Mn _0.3 O ₂ , which is a lithium transition metal phosphate compound having a layered rock salt type crystal structure but not lithium-rich, was used for comparison. Further, LiMn ₂ O ₄ which is a lithium transition metal composite oxide having a crystal structure other than the layered rock salt type (spinel type crystal structure) was also used. In Table 3, LiNi _0.5 Co _0.2 Mn _0.3 O ₂ is indicated as “LinRiO”.

When synthesizing LiFePO ₄ , first, lithium phosphate (Li ₃ PO ₄ ) powder and iron (II) phosphate octahydrate (Fe ₃ (PO ₄ ) ₂ .8H ₂ O) powder Was weighed 50 g. In this case, the mixing ratio of the raw material powder was adjusted so that the molar ratio was Li: Fe: P = 1: 1: 1. Subsequently, the mixture was poured into 200 cc of pure water and stirred to obtain a raw material slurry. Subsequently, 5 g of maltose was added to the raw slurry and stirred in the tank, and then sufficiently mixed and pulverized using a mechanochemical (MC) method (pulverization time = 12 hours) to obtain a pulverized slurry. In this MC method, a planetary ball mill was used. Subsequently, the pulverized slurry was dried and granulated using a spray drying method (intake air temperature = 200 ° C.) to obtain a precursor powder. Finally, the precursor was calcined in an inert gas atmosphere (100% N ₂ ) (calcining temperature = 600 ° C., calcining time = 3 hours) to obtain LiFePO ₄ .

When synthesizing LiFe _0.5 Mn _0.5 PO ₄ , Li ₃ PO ₄ powder, manganese (II) phosphate trihydrate (Mn ₃ (PO ₄ ) ₂ 3H ₂ O) powder, Fe LiFePO ₄ was synthesized except that ₃ (PO ₄ ) ₂ · 8H ₂ O powder was mixed at a molar ratio of Li: Mn: Fe: P = 1: 0.5: 0.5: 1. The same procedure was followed.

When synthesizing LiMnPO ₄ , the molar ratio of Li ₃ PO ₄ powder and Mn ₃ (PO ₄ ) ₂ .3H ₂ O powder is Li: Mn: P = 1: 1: 1. Except for mixing, the same procedure as in the synthesis of LiFePO ₄ was performed.

When Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 Al _0.01 O ₂ is synthesized, nickel sulfate (NiSO ₄ ) powder, cobalt sulfate (CoSO ₄ ) powder, and manganese sulfate (MnSO ₄ ) powder And sodium aluminate (NaAlO ₂ ) powder were mixed and dissolved in water. Subsequently, sodium hydroxide (NaOH) was added to the aqueous solution with sufficient stirring to obtain a coprecipitate (Mn—Ni—Co—Al composite coprecipitate hydroxide). In this case, the mixing ratio of the raw material powders was adjusted so that the molar ratio was Mn: Ni: Co = 60: 20: 20 and Al: (Mn + Ni + Co) = 1: 86. Subsequently, the coprecipitate was washed with water and dried, and then lithium hydroxide monohydrate (LiOH.H ₂ O) was added to obtain a precursor. In this case, the blending ratio was adjusted so that the molar ratio was Li: (Mn + Ni + Co + Al) = 113: 87. Subsequently, the precursor was calcined in the atmosphere (calcination temperature = 800 ° C., calcining time = 10 hours) and then cooled to room temperature to obtain Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 Al _0.01 O ₂ . . In Tables 1 to 3, Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 Al _0.01 O ₂ is indicated as “LiRiO1”.

When synthesizing Li _1.13 (Mn _0.5 Ni _0.2 Co _0.3 ) _0.87 Al _0.01 O ₂ , the mixing ratio of the raw material powder was adjusted so that the molar ratio was Mn: Ni: Co = 50: 20: 30. Except for this, the same procedure as in the case of synthesizing Li _1.13 (Mn _0.6 Ni _0.2 Co _0.2 ) _0.87 Al _0.01 O ₂ was performed. In Tables 1 and 2, Li _1.13 (Mn _0.5 Ni _0.2 Co _0.3 ) _0.87 Al _0.01 O ₂ is indicated as “LiRiO ₂ ”.

  When the battery characteristics (battery capacity, cycle characteristics, load characteristics, storage characteristics, and battery swelling characteristics) of the secondary battery were examined, the results shown in Tables 1 to 3 were obtained.

  When examining the battery capacity and load characteristics, after charging the secondary battery for one cycle in a normal temperature environment (environmental temperature = 23 ° C., the same applies hereinafter), the secondary battery is discharged in the same environment to obtain an initial discharge capacity. (MAh) was measured. In this case, at the time of charging, the battery was charged with a current of 1 C to an upper limit voltage of 4.2 V for 3 hours, and at the time of discharging, the battery was discharged with a current of 0.2 C to a final voltage of 2.5 V. Subsequently, the secondary battery was charged and discharged in the same environment, and the load discharge capacity (mAh) was measured. In this case, at the time of charging, the battery was charged with a current of 1 C to an upper limit voltage of 4.2 V for 3 hours, and at the time of discharging, the battery was discharged with a current of 3 C to a final voltage of 2.5 V. In addition, 0.2C, 1C, or 3C is a current value that can discharge the battery capacity (theoretical capacity) in 5 hours, 1 hour, or 10/3 hours, respectively.

  When investigating the cycle characteristics, after charging and discharging the secondary battery in a room temperature environment and measuring the discharge capacity, the charge capacity was repeated until the total number of cycles reached 500 cycles, and then the discharge capacity was measured. . From this measurement result, capacity retention ratio (%) = (discharge capacity at 500th cycle / discharge capacity at the first cycle) × 100 was calculated. During charging, the battery was charged with a current of 1 C to an upper limit voltage of 4.2 V for 3 hours, and during discharging, the battery was discharged with a current of 1 C to a final voltage of 2.5 V.

  When investigating storage characteristics and battery swell characteristics, the secondary battery is charged in a room temperature environment and the battery thickness (mm) is measured, and then the charged secondary battery is placed in a high temperature environment (environment temperature = 80). The battery thickness (mm) was measured again after storage at 12 ° C. for 12 hours. From this measurement result, swelling (mm) = battery thickness after storage−battery thickness before storage was calculated. Subsequently, after storing the secondary battery in a room temperature environment (23 ° C.) for 12 hours, the secondary battery is discharged in the same environment and then charged and discharged again to measure the storage discharge capacity (mAh). did. At the time of discharging, the battery is discharged at a current of 0.2 C to a final voltage of 2.5 V. At the time of subsequent charging and discharging, the battery is charged at a current of 1 C to an upper limit voltage of 4.2 V for 3 hours, and then at a current of 0.2 C, a final voltage of 2 Discharged to 5V.

  Composition (type, composition, average primary particle size, etc.) of the lithium-containing compound used as the positive electrode active material and composition of the separator 15 (presence / absence of polymer compound layer, presence / absence of inorganic oxide, average primary particle diameter of the inorganic oxide, etc.) ), The battery characteristics showed a specific tendency.

Specifically, when the lithium-containing compound has an olivine type crystal structure (such as LiFePO ₄ ), the initial discharge capacity and the load discharge capacity are compared with those when it has a spinel type crystal structure (LiMn ₂ O ₄ ). Became high. Such a tendency is also observed in the comparison between the case where the lithium-containing compound has a layered rock salt type crystal structure that is rich in lithium (such as LiRiO1) and the case where it has a layered rock salt type crystal structure but is not lithium rich (LinRiO). It was the same.

  Further, when a lithium-containing compound having an olivine type crystal structure or the like is used, the load discharge capacity is higher when the average primary particle diameter is 0.05 μm to 1 μm than when the average primary particle diameter is out of the range. As it became, the swelling decreased. In this case, when the separator 15 includes the polymer compound layer 15B together with the base material layer 15A, the capacity retention ratio and the storage discharge capacity are higher than when the separator 15 does not include the polymer compound layer 15B. At the same time, the swelling decreased.

  In addition, when the separator 15 includes the polymer compound layer 15B, the polymer compound layer 15B includes inorganic oxide particles and has an average primary particle diameter of 0.01 μm to 5 μm. Compared with the case where the particles of the object were not included, the swelling was smaller.

In particular, good results were obtained when the polymer material was PVDF, PVF, PMA or MM and the inorganic oxide was Al ₂ O ₃ , SiO ₂ or TiO ₂ .

  From the results of Tables 1 to 3, the positive electrode contains a lithium-containing compound, the separator contains a base material layer and a polymer compound layer coated and formed thereon, and the lithium-containing compound and polymer compound layer satisfy the above-described conditions. If the condition is satisfied, excellent battery characteristics were obtained.

  As described above, the present technology has been described with reference to the embodiments and examples. However, the present technology is not limited to the aspects described in the embodiments and examples, and various modifications are possible. For example, the case where the battery structure is a laminate film type and the battery element has a winding structure has been described as an example, but the present invention is not limited thereto. The secondary battery of the present technology can be similarly applied to a case where it has another battery structure such as a cylindrical type, a square type, a coin type or a button type, or a case where the battery element has another structure such as a laminated structure. It is.

  Moreover, although the case where Li was used as an electrode reaction material was demonstrated, it is not restricted to this. The electrode reactant may be, for example, another group 1 element such as Na or K, a group 2 element such as Mg or Ca, or another light metal such as Al. 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.

  Moreover, about the average primary particle diameter of a lithium containing compound, the appropriate range derived | led-out from the result of the Example is demonstrated. However, the explanation does not completely deny the possibility that the average primary particle diameter is outside the above-mentioned range. In other words, the appropriate range described above is a particularly preferable range for obtaining the effects of the present technology. Therefore, the average primary particle diameter may slightly deviate from the ranges described above as long as the effects of the present technology can be obtained. The same applies to the average primary particle diameter of the inorganic oxide.

In addition, this technique can also take the following structures.
(1)
Along with a positive electrode and a negative electrode facing each other through a separator, an electrolyte is provided,
The positive electrode includes at least one of lithium-containing compounds represented by the following formula (1) and formula (2):
The average primary particle size of the lithium-containing compound is 0.05 μm to 1 μm,
The separator includes a porous base material layer and a polymer compound layer,
The polymer compound layer is coated and formed on at least one of the surface facing the positive electrode and the surface facing the negative electrode in the base material layer, and the high molecular compound layer in which inorganic oxide particles are dispersed. Including molecular materials,
The average primary particle diameter of the inorganic oxide is 0.01 μm to 5 μm.
Secondary battery.
LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)
Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.)
(2)
The base material layer includes at least one of polyethylene, polypropylene, and polytetrafluoroethylene,
The polymer material includes at least one of polyvinylidene fluoride, polyvinyl formal, polyacrylate, and methyl methacrylate,
The inorganic oxide includes at least one of aluminum oxide, silicon oxide, and titanium oxide.
The secondary battery as described in said (1).
(3)
The positive electrode, the negative electrode, the separator, and the electrolytic solution are housed inside a film-shaped exterior member.
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)
The secondary battery according to any one of (1) to (4) above;
A control unit for controlling the usage state of the secondary battery;
A battery pack comprising: a switch unit that switches a usage state of the secondary battery in accordance with an instruction from the control unit.
(6)
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 a usage state of the secondary battery.
(7)
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.
(8)
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.
(9)
An electronic device comprising the secondary battery according to any one of (1) to (4) as a power supply source.

  DESCRIPTION OF SYMBOLS 10 ... Winding electrode body, 11 ... Positive electrode lead, 12 ... Negative electrode lead, 13 ... Positive electrode, 13A ... Positive electrode collector, 13B ... Positive electrode active material layer, 14 ... Negative electrode, 14A ... Negative electrode collector, 14B ... Negative electrode active Material layer, 15 ... separator, 15A ... base material layer, 15B ... polymer compound layer, 16 ... electrolyte layer, 20 ... exterior member.

Claims (9)

Along with a positive electrode and a negative electrode facing each other through a separator, an electrolyte is provided,
The positive electrode includes a lithium-containing compound;
The lithium-containing compound includes at least one of a compound represented by the following formula (1) and a compound represented by the formula (2),
The average primary particle size of the lithium-containing compound is 0.05 μm to 1 μm,
The separator includes a porous base material layer and a polymer compound layer,
The polymer compound layer is coated and formed on at least one of the surface facing the positive electrode and the surface facing the negative electrode in the base material layer, and the high molecular compound layer in which inorganic oxide particles are dispersed. Including molecular materials,
The average primary particle diameter of the inorganic oxide is 0.01 μm to 5 μm.
Secondary battery.
LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)
Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.) The base material layer includes at least one of polyethylene, polypropylene, and polytetrafluoroethylene,
The polymer material includes at least one of polyvinylidene fluoride, polyvinyl formal, polyacrylate, and methyl methacrylate,
The inorganic oxide includes at least one of aluminum oxide, silicon oxide, and titanium oxide.
The secondary battery according to claim 1. The positive electrode, the negative electrode, the separator, and the electrolytic solution are housed in a film-shaped exterior member.
The secondary battery according to claim 1. Lithium secondary battery,
The secondary battery according to claim 1. A secondary battery,
A control unit for controlling the usage state of the secondary battery;
A switch unit for switching the usage state 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 opposed via a separator,
The positive electrode includes a lithium-containing compound;
The lithium-containing compound includes at least one of a compound represented by the following formula (1) and a compound represented by the formula (2),
The average primary particle size of the lithium-containing compound is 0.05 μm to 1 μm,
The separator includes a porous base material layer and a polymer compound layer,
The polymer compound layer is coated and formed on at least one of the surface facing the positive electrode and the surface facing the negative electrode in the base material layer, and the high molecular compound layer in which inorganic oxide particles are dispersed. Including molecular materials,
The average primary particle diameter of the inorganic oxide is 0.01 μm to 5 μm.
Battery pack.
LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)
Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.) 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 usage state of the secondary battery,
The secondary battery includes an electrolyte solution together with a positive electrode and a negative electrode opposed via a separator,
The positive electrode includes a lithium-containing compound;
The lithium-containing compound includes at least one of a compound represented by the following formula (1) and a compound represented by the formula (2),
The average primary particle size of the lithium-containing compound is 0.05 μm to 1 μm,
The separator includes a porous base material layer and a polymer compound layer,
The polymer compound layer is coated and formed on at least one of the surface facing the positive electrode and the surface facing the negative electrode in the base material layer, and the high molecular compound layer in which inorganic oxide particles are dispersed. Including molecular materials,
The average primary particle diameter of the inorganic oxide is 0.01 μm to 5 μm.
Electric vehicle.
LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)
Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.) 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 opposed via a separator,
The positive electrode includes a lithium-containing compound;
The lithium-containing compound includes at least one of a compound represented by the following formula (1) and a compound represented by the formula (2),
The average primary particle size of the lithium-containing compound is 0.05 μm to 1 μm,
The separator includes a porous base material layer and a polymer compound layer,
The polymer compound layer is coated and formed on at least one of the surface facing the positive electrode and the surface facing the negative electrode in the base material layer, and the high molecular compound layer in which inorganic oxide particles are dispersed. Including molecular materials,
The average primary particle diameter of the inorganic oxide is 0.01 μm to 5 μm.
Power storage system.
LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)
Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.) 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 opposed via a separator,
The positive electrode includes a lithium-containing compound;
The lithium-containing compound includes at least one of a compound represented by the following formula (1) and a compound represented by the formula (2),
The average primary particle size of the lithium-containing compound is 0.05 μm to 1 μm,
The separator includes a porous base material layer and a polymer compound layer,
The polymer compound layer is coated and formed on at least one of the surface facing the positive electrode and the surface facing the negative electrode in the base material layer, and the high molecular compound layer in which inorganic oxide particles are dispersed. Including molecular materials,
The average primary particle diameter of the inorganic oxide is 0.01 μm to 5 μm.
Electric tool.
LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)
Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.) 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 opposed via a separator,
The positive electrode includes a lithium-containing compound;
The lithium-containing compound includes at least one of a compound represented by the following formula (1) and a compound represented by the formula (2),
The average primary particle size of the lithium-containing compound is 0.05 μm to 1 μm,
The separator includes a porous base material layer and a polymer compound layer,
The polymer compound layer is coated and formed on at least one of the surface facing the positive electrode and the surface facing the negative electrode in the base material layer, and the high molecular compound layer in which inorganic oxide particles are dispersed. Including molecular materials,
The average primary particle diameter of the inorganic oxide is 0.01 μm to 5 μm.
Electronics.
LiM1PO ₄ (1)
(M1 is at least one of Fe, Mn and Co.)
Li _{1 + a} (Mn _b Ni _c Co _1-bcd M2 _d ) _1-e O ₂ (2)
(M2 is at least one of Mg, Al, Zn, Ti and V, and a to e are 0.05 ≦ a <0.25, 0.5 ≦ b <0.7, 0 ≦ c <1. -B, 0.001 ≦ d <0.05 and −0.1 ≦ e ≦ 0.2 are satisfied.)

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