JP3605866B2 - Non-aqueous secondary battery - Google Patents

Description

【００３６】
本発明の負極材料を用いたサンプルＮｏ．１〜１１は、比較例のＮｏ．１２に較べ、容量が同等以上で、充放電サイクル性に優れ、かつ高電流を用いた充放電特性に優れ好ましい。
【００３７】
【発明の効果】
本発明のように、正極材料にリチウム含有遷移金属酸化物、負極材料として、少なくとも１種の特定の複合酸化物を用いると高い放電作動電圧、大きな放電容量と優れた充放電サイクル特性、高電流適性を与える非水二次電池を得ることができる。
【図面の簡単な説明】
【図１】実施例に使用した円筒型電池の断面図を示したものである。
【符号の説明】
８ 正極シート
９ 負極シート
１０ セパレーター
１１ 電池缶
１２ 電池蓋
１３ ガスケット
１４ 安全弁[0001]
[Industrial applications]
The present invention relates to a non-aqueous secondary battery having improved charge / discharge characteristics and improved safety.
[0002]
[Prior art]
As a negative electrode material for a non-aqueous secondary battery, lithium metal and lithium alloy are typical, but when they are used, lithium metal grows in a dendritic manner during charge / discharge, causing an internal short circuit or the dendritic metal itself. Is highly active and has a risk of fire. On the other hand, fired carbonaceous materials capable of inserting and releasing lithium have recently come into practical use. The drawback of this carbonaceous material is that it has conductivity in itself, so lithium metal can be deposited on the carbonaceous material during overcharging or rapid charging, eventually depositing dendritic metal Will be. To avoid this, a charger is devised, or a method of preventing overcharge by reducing the amount of the positive electrode active material is adopted.However, in the latter method, the amount of the active material is limited. Therefore, the discharge capacity is also limited. In addition, since the density of the carbonaceous material is relatively small, the discharge capacity is limited in a double sense that the capacity per volume is low.
[0003]
Furthermore, Japanese Patent Application Laid-Open No. 6-275268 discloses SnO, Japanese Patent Application Laid-Open No. 6-325765 discloses a silicon oxide, particularly a silicon oxide in which silicon has a valence of 4 or less. It describes that a composite oxide of tin and another element is used as a negative electrode material. Some of these negative electrode materials have a high discharge potential and a high capacity, but those having an excellent cycle life and an excellent high current suitability have not been developed, so that the performance of the secondary battery is insufficient.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to obtain a non-aqueous secondary battery having improved charge-discharge cycle characteristics, high discharge voltage, high capacity and improved safety. Another object is to obtain a non-aqueous secondary battery excellent in high current suitability.
[0005]
[Means for Solving the Problems]
An object of the present invention is to provide a non-aqueous secondary battery comprising a positive electrode material, a negative electrode material, and a non-aqueous electrolyte containing a lithium salt, wherein the negative electrode material comprises an amorphous oxide mainly composed of a compound represented by the following general formula (2). The amorphous oxide is a substance having a broad scattering band having a peak at 20 ° to 40 ° in 2θ value by X-ray diffraction using CuKα ray, and having a 2θ value of 40 ° or more and 70 ° or more. This is achieved by a non-aqueous secondary battery characterized in that the strongest intensity of the crystalline diffraction lines observed at a temperature of less than 50 ° is 500 times or less the intensity of the diffraction line at the top of the broad scattering band.
SnM ³ p M ⁵ q M ⁷ r General formula (2)
(Where M ³ At least one is S i, G e, P b , P, B, Al, selected from As, M ⁵ At least one is Be, Mg, Ca, Sr, selected from Ba, M ⁷ Is O, p and q each represent a number of 0.001 to 10, and r represents a number of 1.00 to 50. )
[0007]
Saying Cormorant amorphous oxide in the present invention is preferably predominantly amorphous at the time of cell integration. Mainly amorphous and are those having a broad scattering band having an apex at 40 ° from 20 ° in 2θ values by X-ray diffractometry using CuKα ray, 70 ° 40 ° or more at 2 theta values referred to herein The strongest intensity of the crystalline diffraction lines shown below is 500 times or less the diffraction line intensity at the apex of the broad scattering band which is observed at a value of 20 ° or more and 40 ° or less in 2θ value . It is more preferably 100 times or less, particularly preferably 5 times or less, and most preferably has no crystalline diffraction line.
[0009]
The amorphous oxide is mainly composed of a compound represented by the following general formula (2).
SnM ³ pM ⁵ qM ⁷ r General formula (2)
In the formula, M ³ is at least one selected from Si, Ge, Pb, P, B, Al, As, preferably Si, Ge, P, B, Al, and particularly preferably Si, P, B and Al. M ⁵ is at least one selected Be, Mg, Ca, Sr, from Ba, preferably Mg, with Ca, particularly preferably Mg. M ⁷ is O. p and q are each 0.001 to 10, preferably 0.01 to 5, more preferably 0.01 to 1.5, and particularly preferably 0.7 to 1.5. r is 1.00 to 50, preferably 1.00 to 26, and particularly preferably 1.02 to 6. It is preferably represented by the general formula (2) as the general formula (2).
SnSis M ³ pM ⁵ qOt General formula (3)
In the formula, M ³ is at least one selected from Ge, Pb, P, B, Al, and As, preferably Ge, P, B, Al, and particularly preferably P, B, Al. . M ⁵ is the same as in the general formula (2). p, q, and s each represent a number from 0.01 to 5.0, and t represents a number from 1.0 to 26. p and q are more preferably 0.01 to 1.5, and particularly preferably 0.7 to 1.5. t is particularly preferably from 1.02 to 6.
[0010]
A particularly preferred compound of the general formula (3) is represented by the general formula (4).
SnSip M ⁸ qMgr Os In the general formula (4), M ⁸ is at least one selected from Ge, P, B, and Al, and is preferably P, B, or Al. p, q, and r are each 0.01 to 5.0, more preferably 0.01 to 1.5, and particularly preferably 0.7 to 1.5. s represents a number from 1.0 to 26. Particularly preferably, it is 1.02 to 6.
Examples of the composite oxide mainly composed of the oxides represented by the general formulas (1), (2), (3) and (4) include the following, but are not limited thereto.
SnSi _0.8 Mg _0.2 O _2.8 , SnB _0.5 P _0.2 Mg _0.3 O _2.55 , SnSi _0.6 A _10.2 Mg _0.2 O _2.7 , SnSi _{0. 6 A 10.1 B 0.1 P 0.1 Mg} 0.2 O 2.95, SnSi 0.8 Ca 0.2 O 2.8, SnB 0.5 P 0.2 Ca 0.3 O 2. ₅₅ , SnSi _0.6 A _10.2 Ca _0.2 O _0.7 , SnSi _0.6 A _10.1 B _0.1 P _0.1 Ca _0.2 O _2.95 , SnSi _0.5 A _{10 .2 B 0.1 P 0.1 Mg 0.1 O} 2.8, SnSi 0.5 A 10.1 B 0.2 P 0.1 Mg 0.4 O 3.1, SnSi 0.5 A 10 _{.2 B 0.2 Mg 0.2 O 2.8,} SnSi 0.5 A 10.2 B 0.1 P 0.1 Ca 0.1 O 2 _{8, SnSi 0.5 A 10.1 B 0.2} P 0.1 Ca 0.4 O 3.1, SnSi 0.5 A 10.2 B 0.2 Ca 0.2 O 2.8, SnSi 0 _{.8 Ba 0.2 O 2.8, SnB 0.5} P 0.2 Ba 0.3 O 2.55, SnSi 0.6 A 10.2 Ba 0.2 O 2.7, SnSi 0.6 A _{10.1 B 0.1 P 0.1 Ba 0.2 O} 2.95.
[0011]
The general formula (2), (3), (4) in Sn, Si, general formula (2), (3) the valency of M ⁸ of M ³ and the general formula (4) is to be particularly restricted Instead, it may be a single valence or a mixture of each valence. The amounts of M ³ and M ⁵ of the compound represented by the general formula (2) can be continuously changed in the range of 0.01 to 10 molar equivalents with respect to Sn, and the amount of M ⁷ is accordingly changed. (The value of r in the general formula ( 2 )) also changes continuously. The amounts of Si, M ³ and M ⁵ of the compound represented by the general formula (3) can be continuously changed in a range of 0.01 to 5.0 molar equivalents with respect to Sn. The amount of oxygen (the value of t in the general formula (3)) also changes continuously. The amounts of Si, M ⁸ , and Mg of the compound represented by the general formula (4) can be continuously changed in a range of 0.01 to 5.0 molar equivalents with respect to Sn. (The value of s in the general formula (4)) also changes continuously.
[0012]
In the present invention, the compounds represented by the general formulas ( 2 ) to (4) as described above are mainly used as the negative electrode material, so that the charge / discharge cycle characteristics are more excellent, the discharge voltage is higher, and the capacity is higher. It is possible to obtain a non-aqueous secondary battery having high performance and high current characteristics. In the present invention, a particularly excellent effect can be obtained by using a compound containing Sn and having a divalent Sn valence as the negative electrode material. The valence of Sn can be determined by a chemical titration operation. For example, it can be analyzed by the method described on page 165 of Physics and Chemistry of Glasses Vol. 8 No. 4 (1967). It can also be determined from the night shift of Sn by solid state nuclear magnetic resonance (NMR) measurement. For example, in the wide measurement, metal Sn (zero-valent Sn) has an extremely low magnetic field peak at around 7000 ppm relative to Sn (CH ₃ ) ₄ , whereas SnO (= bivalent) has a peak near 100 ppm and SnO (= bivalent). _{At 2} (= tetravalent), it appears near -600 ppm. As described above, when the same ligand is used, the night shift greatly depends on the valence of Sn, which is the central metal. Therefore, the valence can be determined at the peak position obtained by 119Sn-NMR measurement. Various compounds can be included in the negative electrode material of the present invention. For example, Group 1 elements (Li, Na, K, Rb, Cs), transition metals (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, lanthanoid-based metals, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg) and Group 17 elements of the periodic table (F, Cl, Br, I) be able to. Further, it may contain dopants of various compounds (for example, compounds of Sb, In, and Nb) that increase electron conductivity. The amount of the compound to be added is preferably 0 to 20 mol%.
[0013]
In the present invention, as a method for synthesizing the composite oxide mainly containing the oxides represented by the general formulas ( 2 ) to (4), any of a firing method and a solution method can be adopted. For example, when the firing method is described in detail, a Sn compound, an M ² compound and an M ⁴ compound ( M ² Is Si, Ge, Pb, P, B, Al, As, M 4 is Be, Mg, Ca, Sr, Ba) were mixed, it may be fired Seshimere. Examples of the Sn compound include SnO, SnO ₂ , Sn ₂ O ₃ , Sn ₃ O ₄ , Sn ₇ O ₁₃ .H ₂ O, Sn ₈ O ₁₅ , stannous hydroxide, stannic oxyhydroxide, and stannic acid. , Stannous oxalate, stannous phosphate, orthostannic acid, metastannic acid, parastannic acid, stannous fluoride, stannic fluoride, stannous chloride, stannic chloride, stannous bromide , Stannic bromide, stannous iodide, stannic iodide, tin selenide, tin telluride, stannous pyrophosphate, tin phosphide, stannous sulfide, stannic sulfide, etc. be able to. Examples of Si compounds include halogenated organosilicon compounds such as SiO ₂ , SiO, silicon tetrachloride, silicon tetrabromide, trichloromethylsilane, dimethyldichlorosilane, and trimethylchlorosilane; organosilicon compounds such as tetramethylsilane and tetraethylsilane; Examples thereof include alkoxysilane compounds such as methoxysilane and tetraethoxysilane, and hydrosilane compounds such as trichlorohydrosilane. Examples of the Ge compound include GeO ₂ , GeO, alkoxy germanium compounds such as germanium tetrachloride, germanium tetrabromide, germanium tetramethoxide, and germanium tetraethoxide. Examples of the Pb compound include PbO ₂ , PbO, Pb ₂ O ₃ , Pb ₃ O ₄ , PbCl ₂ , lead chlorate, lead perchlorate, lead nitrate, lead carbonate, lead formate, lead acetate, lead tetraacetate, and lead tartrate. , Lead diethoxide, lead di (isopropoxide) and the like. Examples of the P compound include phosphorus pentoxide, phosphorus oxychloride, phosphorus pentachloride, phosphorus trichloride, phosphorus tribromide, trimethylphosphoric acid, triethylphosphoric acid, stannous pyrophosphate, stannous pyrophosphate, and boron phosphate. be able to. Examples of the compound B include boron trioxide, boron trichloride, boron tribromide, boron carbide, boric acid, trimethyl borate, triethyl borate, tripropyl borate, tributyl borate, boron phosphide, and boron phosphate. Examples of the Al compound include aluminum oxide (-alumina, -alumina), aluminum silicate, aluminum tri-iso-propoxide, aluminum tellurite, aluminum chloride, aluminum boride, aluminum phosphide, aluminum phosphate, aluminum lactate, aluminum lactate, Examples thereof include aluminum borate, aluminum sulfide, aluminum sulfate, and aluminum boride .
[0014]
Examples of the Be, Mg, Ca, Sr, and Ba compounds include oxides, hydroxides, carbonates, phosphates, sulfates, nitrates, halides, sulfides, nitrides, carbides, and aluminum compounds. Can be mentioned.
[0015]
As the firing conditions, the heating rate is preferably 4 ° C or more and 2000 ° C or less per minute, more preferably 6 ° C or more and 2000 ° C or less. The temperature is particularly preferably 10 ° C or more and 2000 ° C or less, and the firing temperature is preferably 250 ° C or more and 1500 ° C or less, more preferably 350 ° C or more and 1500 ° C or less, and particularly preferably 500 ° C or more and 1500 ° C or less. And the calcination time is preferably from 0.01 hour to 100 hours, more preferably from 0.5 hour to 70 hours, particularly preferably from 1 hour to 20 hours, and The rate is preferably 2 ° C. or more and 10 ⁷ ° C. or less per minute, more preferably 4 ° C. or more and 10 ⁷ ° C. or less, particularly preferably 6 ° C. or more and 10 ⁷ ° C. or less, and particularly preferably 10 ° C. or more. 10 ⁷ ° C or less.
The rate of temperature rise in the present invention is an average rate of temperature rise from “50% of firing temperature (displayed in ° C.)” to “80% of firing temperature (displayed in ° C.)”. This is the average rate of temperature decrease from "80% of firing temperature (expressed in ° C)" to "50% of firing temperature (expressed in ° C)".
The temperature may be cooled in a baking furnace, or may be taken out of the baking furnace and put into, for example, water to cool. Also, a super-quenching method such as a gun method, a Hammer-Anvil method, a slap method, a gas atomizing method, a plasma spray method, a centrifugal quenching method, a melt drag method, etc. described in page 217 of Ceramics Processing (Gihodo Publishing, 1987) can be used. Alternatively, cooling may be performed using a single-roller method or a twin-roller method described in page 172 of the New Glass Handbook (Maruzen 1991). In the case of a material that melts during firing, a fired product may be continuously taken out while supplying raw materials during firing. In the case of a material that melts during firing, it is preferable to stir the melt.
[0016]
The firing gas atmosphere is preferably an atmosphere having an oxygen content of 5% by volume or less, and more preferably an inert gas atmosphere. Examples of the inert gas include nitrogen, argon, helium, krypton, xenon and the like.
[0017]
The average particle size of the compounds represented by formulas ( 2 ) to (4) used in the present invention is preferably 0.1 to 60 μm, particularly preferably 1.0 to 30 μm, and further preferably 2.0 to 20 μm. In order to obtain a predetermined particle size, a well-known pulverizer or classifier is used. For example, a mortar, a ball mill, a sand mill, a vibrating ball mill, a satellite ball mill, a planetary ball mill, a swirling air jet mill, a sieve, and the like are used. At the time of pulverization, wet pulverization in the presence of water or an organic solvent such as methanol can also be performed if necessary. Classification is preferably performed to obtain a desired particle size. The classification method is not particularly limited, and a sieve, an air classifier, or the like can be used as necessary. Classification can be performed both in a dry type and a wet type.
[0018]
More preferred lithium-containing transition metal oxide cathode materials used in the present invention include lithium compounds / transition metal compounds (where transition metals are Ti, V, Cr, Mn, Fe, Co, Ni, Mo, and W). It is preferable to mix and synthesize so that the total molar ratio of at least one selected) is 0.3 to 2.2. Particularly preferred lithium-containing transition metal oxide cathode materials used in the present invention include lithium compounds / transition metal compounds (where the transition metal is at least one selected from V, Cr, Mn, Fe, Co, and Ni). It is preferable to synthesize them by mixing them so that the total molar ratio becomes 0.3 to 2.2.
Particularly preferred lithium-containing transition metal oxide cathode materials used in the present invention are Li _x QO _y (where Q is a transition metal mainly containing at least one of Co, Mn, Ni, V and Fe), and x = 0.2 to 1.2, y = 1.4 to 3). It is particularly preferable that Q is Co. As Q, other than transition metals, Al, Ga, In, Ge, Sn, Pb, Sb, Bi, Si, P, B, Zn, etc. may be mixed. The mixing amount is preferably 0 to 30 mol% based on the transition metal.
[0019]
Preferred specific lithium-containing metal oxide positive electrode material for use in the present _{invention, Lix CoO 2, Lix NiO 2} , Lix MnO 2, Lix Coa Ni 1-a O 2, Lix Cob V 1-b Oz, Lix Cob _{Fe 1-b O 2, Lix} Mn 2 O 4, Lix Mnc Co 2-c O 4, Lix Mnc Ni 2-c O 4, Lix Mnc V 2-c O 4, Lix Mnc Fe 2-c O 4 ( wherein Where x = 0.7-1.2, a = 0.1-0.9, b = 0.8-0.98, c = 1.6-1.96, z = 2.01-2.3 ).
The most preferred lithium-containing transition metal oxide positive electrode material for use in the present _{invention, Lix CoO 2, Lix NiO 2} , Lix MnO 2, Lix Coa Ni 1-a O 2, Lix Mn 2 O 4, Lix Cob V 1- _b Oz (where x = 0.7 to 1.2, a = 0.1 to 0.9, b = 0.9 to 0.98, z = 2.01 to 2.3).
Here, the above-mentioned x value is a value before the start of charge / discharge, and increases / decreases due to charge / discharge.
[0020]
The positive / negative electrode used in the non-aqueous secondary battery of the present invention can be prepared by coating a positive electrode mixture or a negative electrode mixture on a current collector or forming a pellet. The positive electrode or negative electrode mixture can contain a conductive agent, a binder, a dispersant, a filler, an ionic conductive agent, a pressure enhancer, and various additives, respectively, in addition to the positive electrode material or the negative electrode material, respectively.
[0021]
Further, the negative electrode material of the present invention can be used by inserting a light metal, particularly lithium. The method of inserting lithium is preferably an electrochemical, chemical or thermal method.
The amount of lithium inserted into the negative electrode material of the present invention may be up to approximation of the deposition potential of lithium. For example, it is preferably 50 to 700 mol% per the above-mentioned preferable negative electrode material. Particularly, 100 to 600 mol% is preferable.
The conductive agent in the positive electrode and the negative electrode that can be used in the present invention is graphite, acetylene black, carbon black, Ketjen black, carbon fiber or metal powder, metal fiber, or a polyphenylene derivative, and graphite and acetylene black are particularly preferable.
Binders in the positive electrode and the negative electrode that can be used in the present invention are polyacrylic acid, carboxymethyl cellulose, polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl alcohol, starch, regenerated cellulose, diacetyl cellulose, hydroxypropyl cellulose, polyvinyl chloride, polyvinyl chloride. Pyrrolidone, polyethylene, polypropylene, SBR, EPDM, sulfonated EPDM, fluororubber, polybutadiene, polyethylene oxide, and particularly preferred are polyacrylic acid, carboxymethylcellulose, polytetrafluoroethylene, and polyvinylidene fluoride.
[0022]
The support or current collector for the positive electrode and the negative electrode that can be used in the present invention is, as a material, the positive electrode is aluminum, stainless steel, nickel, titanium, or an alloy thereof, and the negative electrode is copper, stainless steel, nickel, titanium. Or alloys thereof, in the form of foil, expanded metal, punched metal, or wire mesh. In particular, an aluminum foil is preferable for the positive electrode, and a copper foil is preferable for the negative electrode.
The separator that can be used in the present invention has a high ion permeability, a predetermined mechanical strength, and may be any insulating thin film. As the material, olefin-based polymers, fluorine-based polymers, cellulose-based polymers, polyimides, nylons, Glass fiber and alumina fiber are used, and as a form, a nonwoven fabric, a woven fabric, or a microporous film is used. In particular, the material is preferably polypropylene, polyethylene, a mixture of polypropylene and polyethylene, a mixture of polypropylene and Teflon, and a mixture of polyethylene and Teflon, and the form is preferably a microporous film. In particular, a microporous film having a pore size of 0.01 to 1 μm and a thickness of 5 to 50 μm is preferable.
[0023]
Electrolyte solution that can be used in the present invention, propylene carbonate, ethylene carbonate, butylene carbonate, dimethyl carbonate, diethyl carbonate, 1,2-dimethoxyethane, γ-butyrolactone, tetrahydrofuran, 2-methyltetrahydrofuran, dimethylsulfoxide, as an organic solvent, Dioxolane, 1,3-dioxolane, formamide, dimethylformamide, nitromethane, acetonitrile, methyl formate, methyl acetate, methyl propionate, phosphoric acid triester, trimethoxymethane, dioxolane derivative, sulfolane, 3-methyl-2-oxazolidinone, propylene carbonate A mixture of at least one of a derivative, a tetrahydro derivative, diethyl ether, and 1,3-propane sultone; _{LiClO 4, LiBF 4, LiPF 6} , LiCF 3 SO 3, LiCF 3 CO 2, LiAsF 6, LiSbF 6, LiB 10 Cl 10, lower aliphatic lithium _carboxylate, LiAlCl 4, LiCl, LiBr, LiI, chloroborane lithium, It is preferable to dissolve one or more salts of lithium tetraphenylborate. In particular, a solvent obtained by dissolving LiCF ₃ SO ₃ , LiClO ₄ , LiBF ₄ , and / or LiPF ₆ in a mixed solvent of propylene carbonate or ethylene carbonate with 1,2-dimethoxyethane and / or diethyl carbonate is preferable. Preferably, it contains carbonate and LiPF ₆ .
[0024]
The shape of the battery can be applied to any of buttons, coins, sheets, cylinders, corners, and the like. In the case of buttons and coins, the mixture is press-formed into pellets, and in the case of sheets, squares and cylinders, the mixture is applied on a current collector, dried, dehydrated, and pressed. A battery is formed by inserting an electrode wound with a pellet, a sheet, or a separator into a battery can, electrically connecting the can and the electrode, injecting an electrolyte, and sealing the battery. At this time, a safety valve can be used as a sealing plate. Further, it is preferable to use a PTC element in order to guarantee the safety of the battery.
[0025]
The bottomed battery outer can that can be used in the present invention is made of a nickel-plated iron steel plate, a stainless steel plate (SUS304, SUS304L, SUS304N, SUS316, SUS316L, SUS430, SUS444, etc.) or a nickel-plated stainless steel plate (material). Ibid.), Aluminum or its alloys, nickel, titanium, and copper, and has a shape of a perfect circular cylinder, an elliptical cylinder, a square cylinder, or a rectangular cylinder. In particular, when the outer can also serves as the negative electrode terminal, a stainless steel sheet or a nickel-plated iron steel sheet is preferable, and when the outer can also serves as the positive electrode terminal, a stainless steel sheet, aluminum, or an alloy thereof is preferable.
[0026]
The gasket that can be used in the present invention is, as a material, an olefin-based polymer, a fluorine-based polymer, a cellulose-based polymer, a polyimide, or a polyamide.From the viewpoint of organic solvent resistance and low moisture permeability, an olefin-based polymer is preferable. Polymers are preferred. Further, it is preferably a block copolymer of propylene and ethylene.
[0027]
The battery of the present invention is covered with an exterior material as necessary. Examples of the exterior material include a heat-shrinkable tube, an adhesive tape, a metal film, paper, cloth, paint, a plastic case, and the like. Further, at least a part of the exterior may be provided with a portion that changes color by heat so that the heat history during use can be recognized.
The battery of the present invention is assembled in a battery pack in a plural number in series and / or parallel as required. In addition to safety elements such as positive temperature coefficient resistors, temperature fuses, fuses and / or current interrupting elements, battery packs have safety circuits (monitoring the voltage, temperature, current, etc. of each battery and / or assembled battery as a whole, Then, a circuit having a function of interrupting the current may be provided. In addition to the positive and negative terminals of each battery, the battery pack should have external terminals such as the positive and negative terminals of each battery, the temperature detection terminals of the entire battery and each battery, and the current detection terminals of the entire battery. You can also. The battery pack may include a voltage conversion circuit (such as a DC-DC converter). The connection of each battery may be fixed by welding a lead plate, or may be fixed by a socket or the like so that it can be easily detached. Further, the battery pack may be provided with a display function such as a remaining battery capacity, whether or not charging is performed, and the number of times of use.
[0028]
The battery of the present invention is used for various devices. In particular, video movies, portable VCRs with built-in monitors, movie cameras with built-in monitors, compact cameras, single-lens reflex cameras, disposable cameras, film with lenses, notebook computers, notebook word processors, electronic organizers, mobile phones, cordless phones, hairdressers, It is preferably used for electric tools, electric mixers, automobiles and the like.
[0029]
【Example】
Hereinafter, the present invention will be described in more detail by way of specific examples. However, the present invention is not limited to the examples unless it exceeds the gist of the invention.
Synthesis Example 1
13.5 g of tin monoxide, 4.8 g of silicon dioxide and 0.64 g of magnesium oxide were dry-mixed, placed in an alumina crucible, and heated to 1000 ° C. at 15 ° C./min in an argon atmosphere. After firing at 1150 ° C. for 12 hours, the temperature was lowered to room temperature at 10 ° C./minute, taken out of the firing furnace, coarsely pulverized, and further pulverized with a jet mill to obtain SnSi _0.8 having an average particle size of 4.5 μm. Mg _0.2 O _2.8 was obtained. (Compound 1-A)
Further, in the X-ray diffraction method using CuKα ray, it has a broad peak having an apex at 28 ° in the vicinity of 28 °, and a crystalline diffraction line is observed at a 2θ value of 40 ° or more and 70 ° or less. Did not.
In the same manner, stoichiometric amounts of raw materials were mixed, fired, and pulverized to synthesize the following compounds. Further, those compounds had a broad scattering band having a peak at 20 ° to 40 ° in 2θ value in an X-ray diffraction method using CuKα ray. In addition, when the diffraction line intensity at the apex of the broad scattering band seen at 20 ° or more and 40 ° or less at 2θ value is A, when crystalline diffraction lines are seen at 40 ° or more and 70 ° or less at 2θ value, When the strong intensity is B (B = 0 when there is no crystalline diffraction line), the value of B / A is shown together with the compound number. In addition, 1 / A was B / A = 0.
[0030]
In the same manner, stoichiometric amounts of raw materials were mixed, fired, and pulverized to obtain the following compounds. SnSi _0.8 Mg _0.2 O _2.8 (1-B), SnSi _0.6 A _10.2 Mg _0.2 O _2.7 (1-C), SnSi _0.6 P _0.2 Mg _{0 .2 O 2.9 (1-D)} , SnSi 0.6 A 10.1 B 0.2 Mg 0.1 O 2.75 (1-E), SnSi 0.5 P 0.1 B 0.1 Ca _0.3 O _2.7 (1-F). SnSiO ₃ (1-X; Comparative Example).
The B / A values of these compounds were all 0.
[0031]
Synthesis Example 2
13.5 g of tin monoxide, 4.8 g of silicon dioxide and 0.64 g of magnesium oxide were dry-mixed, placed in an alumina crucible, and heated to 1000 ° C. at 15 ° C./min in an argon atmosphere. After calcining at 1200 ° C. for 4 hours, the mixture was poured on a stainless steel wheel under an argon atmosphere and rapidly cooled (cooling rate: 200 ° C./min). The compound was coarsely pulverized and further pulverized with a vibration mill to obtain SnSi _0.8 Mg _0.2 O _2.8 having an average particle size of 3.5 μm. (Compound 2-A)
B / A = 0 in X-ray diffraction.
[0032]
Synthesis Example 3
13.5 g of tin monoxide, 4.8 g of silicon dioxide and 0.64 g of magnesium oxide were dry-mixed, placed in an alumina crucible, and fired at 1200 ° C. for 10 hours in the air. After calcination, the mixture was cooled to room temperature (cooling rate: 4 ° / min), taken out of the calcination furnace, and pulverized by a jet mill to obtain SnSi _0.8 Mg _0.2 O _2.8 having an average particle size of 4 μm. (Compound 3-A)
B / A = 0 in X-ray diffraction.
In the same manner, stoichiometric amounts of raw materials are mixed, fired, and pulverized, and SnSi _0.5 B _0.3 Mg _0.2 O _2.6 (3-B, B / A = 2.8). _{, SnSi 0.7 P 0.1 Mg 0.2 O} 2.2 (3-C, B / A = 6.4), SnSi 0.5 B 0.3 P 0.1 Mg 0.1 O 2. ₆ (3-D, B / A = 3.2) was obtained.
[0033]
Example 1
As the negative electrode material, the compound 1-A synthesized in Synthesis Example 1 was mixed at a ratio of 86% by weight, 6% by weight of flaky graphite and 3% by weight of acetylene black, and polyvinylidene fluoride was further used as a binder. Was added to 4% by weight of an aqueous dispersion and 1% by weight of carboxymethyl cellulose, and kneaded with water as a medium to prepare a slurry. The slurry was applied to both surfaces of a copper foil having a thickness of 18 μm by an extrusion method, dried, compression-molded by a calender press, and cut into a predetermined width and length to prepare a strip-shaped negative electrode sheet. The thickness of the negative electrode sheet was 124 μm. 87% by weight of LiCoO ₂ , 6% by weight of flaky graphite, 3% by weight of acetylene black as a positive electrode material, and 3% by weight of a polytetrafluoroethylene aqueous dispersion and 1% by weight of sodium polyacrylate as a binder were added. The slurry obtained by kneading with water as a medium was applied to both sides of a 20-μm-thick aluminum foil in the same manner as described above, dried, pressed and cut. Then, a belt-shaped positive electrode sheet of 220 μm was produced.
After nickel and aluminum lead plates were spot-welded to the ends of the negative electrode sheet and the positive electrode sheet, dehydration drying was performed at 150 ° C. for 2 hours in dry air having a dew point of −40 ° C. or less.
Further, the dehydrated and dried positive electrode sheet (8), the microporous polypropylene film separator (Celgard 2400), the dehydrated and dried negative electrode sheet (9) and the separator (10) are laminated in this order, and this is spirally wound by a winding machine. Turned.
[0034]
This wound body was housed in a nickel-plated iron bottomed cylindrical battery can (11) also serving as a negative electrode terminal. An electrolyte containing 0.9 and 0.1 mol of LiPF ₆ and LiBF ₄ per liter, respectively, and a solvent consisting of a 2: 2: 6 volume mixture of ethylene carbonate, butylene carbonate and dimethyl carbonate was injected into the battery can. A battery lid (12) having a positive electrode terminal was caulked via a gasket (13) to produce a cylindrical battery. The positive electrode terminal (12) was connected to the positive electrode sheet (8) and the battery can (11) was connected to the negative electrode sheet (9) by a lead terminal in advance. FIG. 1 shows a cross section of a cylindrical battery. (14) is a safety valve.
A cylindrical battery was manufactured in the same manner except that the anode material 1-A was changed to the compounds shown in Table 1.
Charge and discharge conditions were 4.3 to 2.7 V, 1 mA / cm ² . The results are shown below.
[0035]
Description of abbreviations a: negative electrode material, b: first discharge capacity (mAh per 1 g of negative electrode material), c: charge / discharge cycle property (the number of cycles to be 85% of the first capacity), d: charge / discharge current Ratio of first discharge capacity at 5 mA / first discharge capacity at 1 mA

[0036]
Sample No. using the negative electrode material of the present invention. Nos. 1 to 11 are Nos. Of Comparative Examples. As compared with No. 12, the capacity is equal to or more than that, the charge / discharge cycle property is excellent, and the charge / discharge characteristics using a high current are excellent.
[0037]
【The invention's effect】
As in the present invention, when a lithium-containing transition metal oxide is used as a positive electrode material and at least one specific composite oxide is used as a negative electrode material, a high discharge operating voltage, a large discharge capacity and excellent charge / discharge cycle characteristics, a high current A non-aqueous secondary battery giving appropriateness can be obtained.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a cylindrical battery used in Examples.
[Explanation of symbols]
8 Positive electrode sheet 9 Negative electrode sheet 10 Separator 11 Battery can 12 Battery lid 13 Gasket 14 Safety valve

Claims (7)

In a non-aqueous secondary battery comprising a positive electrode material, a negative electrode material, and a non-aqueous electrolyte containing a lithium salt, the negative electrode material comprises an amorphous oxide mainly containing a compound represented by the following general formula (2); The crystalline oxide is a substance having a broad scattering band having an apex at 20 ° to 40 ° in 2θ value by X-ray diffraction using CuKα ray, and a crystal having a 2θ value of 40 ° or more and 70 ° or less. A non-aqueous secondary battery characterized in that the strongest intensity of the diffracted rays is 500 times or less the intensity of the diffracted rays at the apex of the broad scattering band.
SnM ³ p M ⁵ q M ⁷ r General formula (2)
(Where M ³ At least one is S i, G e, P b , P, B, Al, selected from As, M ⁵ At least one is Be, Mg, Ca, Sr, selected from Ba, M ⁷ Is O, p and q each represent a number of 0.001 to 10, and r represents a number of 1.00 to 50. ) 2. The non-aqueous secondary battery according to claim 1, wherein the negative electrode material is mainly an amorphous oxide when incorporated in the battery. At least one of the negative electrode materials is represented by the following general formula (3)
SnSis M ³ pM ⁵ qOt General formula (3)
(In the formula, M ³ is at least one selected from Ge, Pb, P, B, and Al, M ⁵ is the same as in the general formula (2), p, q, and s are each 0.01 to 5.0, and t is claim 1 or claim 2 nonaqueous secondary battery, wherein the mainly a compound represented by the representative.) the number of 1.0 to 26. Heated at below 2000 ° C. heating rate per minute 10 ° C. or more negative electrode material, and 250 ° C. or higher 1500 ° C. 0.01 hours to 100 hours fired and following cooling rate per minute 10 ⁷ ° C. 2 ° C. or more or less below The non-aqueous secondary battery according to any one of claims 1 to 3 , wherein the non-aqueous secondary battery is obtained. The non-aqueous secondary battery according to any one of claims 1 to 4 , wherein the positive electrode material is a lithium-containing transition metal oxide. At least one of the positive electrode materials is Li _x QO _y (wherein Q is a transition metal containing at least one of Co, Mn, Ni, V, and Fe; x = 0.2 to 1.2, y = 1.4 to 3), wherein the non-aqueous secondary battery according to any one of claims 1 to 5 , wherein At least one positive electrode _{material, Lix CoO 2, Lix NiO 2} , Lix MnO 2, Lix Coa Ni 1-a O 2, Lix Cob V 1-b O z, Lix Cob Fe 1-b O 2, Lix Mn ₂ O ₄ , Lix Mnc Co ₂ -CO ₄ , Lix Mnc Ni ₂ -CO ₄ , Lix Mnc V ₂ -CO ₄ , Lix Mnc Fe ₂ -CO ₄ (where x = 0.2 to 1) 0.2, a = 0.1 to 0.9, b = 0.8 to 0.98, c = 1.6 to 1.96, z = 2.01 to 2.3). nonaqueous secondary battery according to any one of claims 1 to 6.

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