JP2007294286A - Negative electrode for nonaqueous system secondary battery and nonaqueous system secondary battery using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a negative electrode for a nonaqueous system secondary battery capable of discharging at a current density of several tens A/g with respect to the weight of negative active material, having high electrode density, and having high capacity per the weight of negative active material, responding to a high request level to high energy density and high output/high rate discharge characteristics in a power storage system, such as an ultra-high output device having an energy density of 100 Wh/L and an output characteristic exceeding 300 C, not present until now; and to provide a nonaqueous system secondary battery having high energy density/high output using this negative electrode. <P>SOLUTION: The negative electrode for the nonaqueous system secondary battery contains an insoluble infusible substrate having a ratio of hydrogen atom to carbon atom of 0.60-0.05 and a spacing of (002) planes of 3.6 Å or more, as the main component, and the average particle diameter of the insoluble infusible substrate is 2.0 μm or less, and lithium of 500 mAh/g or more with respect to the weight of the insoluble infusible substrate is previously carried. The nonaqueous system secondary battery using this negative electrode is manufactured. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a negative electrode for a non-aqueous secondary battery used for a non-aqueous secondary battery having high energy density and high output / high rate charging characteristics, and a non-aqueous secondary battery including the negative electrode.

  In recent years, midnight power storage systems, home-use distributed power storage systems based on solar power generation technology, and power storage systems for electric vehicles have attracted attention from the viewpoint of the effective use of energy aimed at preserving the global environment and conserving resources. Yes. Among them, in a combination of a high-efficiency engine and a power storage system (for example, a hybrid electric vehicle) or a combination of a fuel cell and a power storage system (for example, a fuel cell electric vehicle), the engine or the fuel cell operates at maximum efficiency. In order to cope with output fluctuation or energy regeneration on the load side, high output discharge characteristics and / or high rate charging characteristics are required on the power storage system side. In order to meet this demand, in power storage systems, higher output of lithium ion batteries or higher energy density of capacitors represented by electric double layer capacitors are being studied.

  Lithium ion batteries, which are representative of high energy density secondary batteries, have been made of carbon materials such as graphite capable of being doped / undoped with lithium ions for the negative electrode. As materials that can be used as negative electrode materials for lithium ion batteries, graphite and amorphous carbon materials are generally used. However, high power non-aqueous secondary batteries have high output discharge characteristics / high rate charge characteristics. Amorphous carbon materials that are superior to graphite are being studied.

  On the other hand, there is a material group (generally referred to as hydrographene in Non-Patent Document 1) in which hydrogen is bonded to the periphery of the carbon hexagonal network as a material capable of doping and dedoping lithium ions. 1. A heat-treated product of an aromatic condensation polymer composed of carbon, hydrogen, and oxygen described in 1, having a hydrogen / carbon atom ratio of 0.60 to 0.15 and containing a polyacene skeleton structure There is an infusible substrate. An insoluble and infusible substrate containing a polyacene-based skeleton structure is called PAS in Non-Patent Document 2 (PAS is an abbreviation for Polyacenic Semiconductor), and its feature is that it can be doped / undoped with lithium ions about 3 times that of graphite. It is described in Non-Patent Document 3. In addition, a non-aqueous secondary material in which a high voltage is obtained by using a non-insoluble infusible substrate containing this polyacene-based skeleton structure and lithium is previously supported on the negative electrode (hereinafter sometimes referred to as pre-doping) to obtain a high voltage. The batteries are described in Non-Patent Document 4, Patent Document 2, Non-Patent Document 5, and Patent Document 3, all of which have a high capacity that is characteristic of an insoluble and infusible substrate (PAS) containing a polyacene-based skeleton structure. This is an approach to a high energy type battery that has been utilized, and there is no description regarding application to a non-aqueous lithium ion battery having high energy density and high output.

  Another example of a material in which hydrogen is bonded to the periphery of the carbon hexagonal network surface (hydrographene) is obtained by subjecting a raw material mainly composed of pitch to a thermal reaction, and a hydrogen / carbon atomic ratio of 0.1. There is a material that is 35 to 0.05, and it is described that lithium of 1000 mAh / g or more exceeding the PAS can be doped / undoped (Patent Document 4, Non-Patent Document 6). Non-Patent Document 6 and Non-Patent Document 7 refer to this material as PAHs (abbreviation of Polycyclic Aromatic Hydrocarbons), which describes that the shape of a typical carbon hexagonal mesh surface is a disk shape. Non-Patent Document 8 discloses a lithium secondary battery using the PAHs as a negative electrode, and a small secondary battery having a capacity about twice that of a commercially available lithium ion battery is obtained. This is also an approach to a high energy type battery utilizing the high capacity that is characteristic of PAHs, and there is no description regarding application to a non-aqueous lithium ion battery having a high energy density and a high output.

Recently, higher energy density of capacitors has begun to be studied, and development of lithium-type capacitors containing activated carbon for the positive electrode, materials capable of being doped / undoped with lithium ions for the negative electrode, and lithium salts in the electrolyte is also underway (Patent Literature). 5). Non-Patent Document 9 and Non-Patent Document 10 disclose capacitors using the above-mentioned PAS as a negative electrode and a lithium-based electrolyte in which lithium is supported on the negative electrode in advance. The energy density thereof is 20 Wh / It is about L (12 Wh / kg), and in order to satisfy the above requirements, further higher energy density and higher output are required.
T.A. Yamabe, M .; Fujii, S .; Mori, H .; Kinoshita, S .; Yata: Synth. Met. , 145, 31 (2004) JP 59-3806 S. Yata, Y. et al. Hato, K .; Sakurai, T .; Osaki, K .; Tanaka, T .; Yamabe: Synth. Met. , 18, 645 (1987) S. Yata, H .; Kinoshita, M .; Komori, N .; Ando, T.A. Kashiwamura, T .; Harada, K .; Tanaka, T .; Yamabe: Synth. Met. 62, 153 (1994) Shigeru Yada, Industrial Materials, Vol. 40, no. 5, 32 (1992) JP-A-3-233860 S. Yata, Y. et al. Hato, H .; Kinoshita, N .; Ando, A.D. Anekawa, T .; Hashimoto, M .; Yamaguchi, K .; Tanaka, T .; Yamabe: Synth. Met. 73, 273 (1995) WO98 / 33227 JP 2000-251885 A S. Wang, S.W. Yata, J .; Nagano, Y .; Okano, H.M. Kinoshita, H .; Kikuta, T .; Yamabe: J. et al. Electrochem. Soc. , 147 (7), 2498 (2000) Shigetaka Yada et al .: Molecular Functional Materials and Device Development, 77 (2004) Shigetoku Yada et al .: Molecular Functional Materials and Device Development, 428 (2004) WO2002 / 41420 Publication Nobuo Ando et al., Development of Lithium Ion Capacitors (1) "Abstracts of the 46th Battery Conference", November 2005, 1C12, p294 Shinichi Tazaki et al., Development of Lithium Ion Capacitors (2) “Abstracts of the 46th Battery Conference”, November 2005, 1C13, p296

  High levels of demand for high energy density and high output / high rate charging characteristics in power storage systems are high. For example, there is a demand for the realization of ultra-high output devices having unprecedented energy density of 100 Wh / L and output characteristics exceeding 300 C. . In order to realize this ultra-high output device, both the negative electrode and the positive electrode require electrodes with both high capacity and high output / high rate charging characteristics, and there is a high level of capacity and output characteristics per weight or volume. Necessary. For this reason, in order to realize this ultra-high output device, the negative electrode can first be discharged at a current density of about several tens of A / g with respect to the weight of the active material. Need to have a high capacity. However, in the conventional negative electrode active material for lithium ion batteries, the capacity is about 100 to 300 mAh / g per weight, and the output is 30 C level when the negative electrode thickness is a practical thickness (for example, 30 μm or more). That is, the dischargeable current density is 10 A / g or less per weight of the negative electrode active material and does not satisfy the above requirement. Therefore, the present invention is capable of doping and dedoping lithium ions, has a high capacity, and has a high energy density and unprecedented high output characteristics. The object is to provide an aqueous secondary battery.

  As a result of conducting research while paying attention to the problems of the prior art as described above, the present inventor used an insoluble infusible substrate having a crystal plane 002 plane spacing of 3.6 mm or more for the negative electrode, By controlling the particle size of the insoluble and infusible substrate and the amount of lithium supported on the insoluble and infusible substrate in advance, a high output discharge (e.g., when discharging at a current density of 40 A / g) The inventors have found a negative electrode capable of discharging 30 mAh / g or more per active material weight, and have completed the present invention.

  The negative electrode for a non-aqueous secondary battery according to claim 1 has a hydrogen atom / carbon atom ratio of 0.60 to 0.05 and a crystal plane 002 plane spacing of 3.6 mm or more. In a negative electrode for a non-aqueous secondary battery having a fusible substrate as a main component, an insoluble infusible substrate having an average particle diameter of 2.0 μm or less and 500 mAh / g or more of lithium per weight of the insoluble infusible substrate It is characterized by being carried in advance.

The negative electrode for a non-aqueous secondary battery according to claim 2 is characterized in that the electrode density is 0.8 g / cm ³ or more.

  The negative electrode for a non-aqueous secondary battery according to claim 3 is characterized in that the electrode thickness is 30 μm or more.

  The negative electrode for a non-aqueous secondary battery according to claim 4 has a discharge of 30 mAh / g or more per weight of the insoluble infusible substrate when discharged at a current density of 40 A / g per weight of the insoluble infusible substrate. It is characterized by being possible.

  According to the configuration of the first to fourth aspects, a negative electrode for a non-aqueous secondary battery having high energy density and unprecedented high output characteristics can be obtained.

  The non-aqueous secondary battery according to claim 5 is a non-aqueous secondary battery comprising a non-aqueous electrolyte solution in which a positive electrode, a negative electrode, a separator, and a lithium salt are dissolved in a non-aqueous solvent. Any one of the negative electrodes described above is used.

  According to the fifth aspect, a non-aqueous secondary battery having both high energy density and high output can be obtained.

  The negative electrode for a non-aqueous secondary battery according to the present invention is an insoluble infusible substrate having a hydrogen atom / carbon atom ratio of 0.60 to 0.05 and a surface spacing of crystal planes of 002 of 3.6 mm or more. The insoluble infusible substrate has an average particle size of 2.0 μm or less, and lithium of 500 mAh / g or more per weight of the insoluble infusible substrate is previously supported. Therefore, for example, it is possible to obtain a negative electrode for a non-aqueous secondary battery having high output characteristics and high capacity that can be discharged at a very high current density of 40 A / g or more per weight of the negative electrode active material. Further, by using this negative electrode, there is an effect that a non-aqueous secondary battery having both high energy density and high output can be obtained.

  An embodiment of the present invention will be described as follows.

  The negative electrode for a non-aqueous secondary battery according to the present invention is an insoluble infusible substrate having a hydrogen atom / carbon atom ratio of 0.60 to 0.05 and a surface spacing of crystal planes of 002 of 3.6 mm or more. The insoluble infusible substrate has an average particle size of 2.0 μm or less, and 500 mAh / g or more of lithium is previously supported per weight of the insoluble infusible substrate.

  The insoluble and infusible substrate in the present invention can be obtained, for example, by heat-treating the following aromatic condensation polymer. The aromatic condensation polymer is a condensate of an aromatic hydrocarbon compound, for example, a condensate of an aromatic hydrocarbon compound and an aldehyde. As the aromatic hydrocarbon compound, for example, so-called phenols such as phenol, cresol, xylenol and the like are suitable. For example, it may be methylene bisphenols, or may be hydroxy biphenyls or hydroxynaphthalenes. Of these, phenols, particularly phenol, are suitable for practical use. As the aromatic condensation polymer, a part of the aromatic hydrocarbon compound having a phenolic hydroxyl group is substituted with an aromatic hydrocarbon compound having no phenolic hydroxyl group, for example, xylene, toluene, aniline, etc. A modified aromatic condensation polymer such as a condensate of phenol, xylene and formaldehyde can also be used, and a modified aromatic condensation polymer substituted with melamine or urea can also be used. Furan resins are also suitable. Moreover, as said aldehyde, aldehydes, such as formaldehyde, acetaldehyde, a furfural, can be used, However, Formaldehyde is suitable. The phenol formaldehyde condensate may be novolak type, resol type, or a mixture thereof. It can also be obtained by heat-treating thermosetting resins such as epoxy resins, unsaturated polyesters, alkyd resins, urethane resins and ebonites, cellulose raw materials such as coconut shells, wood chips and bamboo, polyimides and the like. Although the present invention does not limit the raw material of the insoluble infusible substrate, the insoluble infusible substrate of the present invention is characterized in that the interplanar spacing of the crystal plane 002 is as large as 3.6 mm or more, and is subjected to a heat treatment described later. If a raw material that reaches the insoluble and infusible substrate in the solid phase without being liquefied is selected, this structure is easily obtained.

  The insoluble and infusible substrate of the present invention is obtained, for example, by heat-treating the raw materials exemplified above, and is described in JP-A-59-3806, JP-A-60-170163, and the like. One example is an insoluble and infusible substrate having a polyacene skeleton structure. The insoluble and infusible substrate of the present invention can be produced, for example, as follows. The raw materials exemplified above are gradually heated to an appropriate temperature of, for example, 400 ° C. to 800 ° C. in a non-oxidizing atmosphere (including a vacuum), whereby a hydrogen atom / carbon atom ratio (hereinafter referred to as H). / C)) can be obtained from 0.60 to 0.05 insoluble and infusible substrate. H / C is preferably 0.50 to 0.05, more preferably 0.35 to 0.05, still more preferably 0.35 to 0.1, and when H / C exceeds the upper limit, aromatic Since the polycyclic structure is not sufficiently developed, lithium doping and dedoping cannot be carried out smoothly. When a battery is assembled, the charge / discharge efficiency is reduced, or the output that is the object of the present invention is not achieved. Not enough. Further, when H / C is lower than the lower limit, the capacity of the insoluble and infusible substrate is decreased, so that the energy density of a battery using the same is decreased, or the output that is the object of the present invention cannot be sufficiently obtained. .

Further, an insoluble and infusible substrate having a specific surface area by the BET method of 600 m ² / g or more can be obtained by the method described in JP-A-60-170163. For example, a solution containing an initial condensation product of an aromatic condensation polymer and an inorganic salt such as zinc chloride is prepared, and the solution is heated and cured in a mold. The cured product thus obtained is gradually heated to a temperature of 350 ° C. to 800 ° C., preferably 400 ° C. to 750 ° C. in a non-oxidizing atmosphere (including vacuum), and then water or dilute hydrochloric acid. By thoroughly washing with, for example, an insoluble and infusible substrate having the above H / C and having a specific surface area by the BET method of, for example, 600 m ² / g or more can be obtained. When the specific surface area of the insoluble and infusible substrate in the present invention is less than 1000 m ² / g, preferably less than 700 m ² / g, more preferably less than 600 m ² / g, and the specific surface area is 1000 m ² / g or more, When the negative electrode density using the insoluble and infusible substrate is lowered, the energy density of the battery using the same is lowered, which is not preferable.

  According to X-ray diffraction (Cu-Kα), the insoluble and infusible substrate used in the present invention has a main peak position represented by 2θ of 25 ° or less, and 41 to 41 in addition to the main peak. There is another broad peak between 46 °. The main peak existing at 25 ° or less is derived from the crystal plane 002. The spacing between the crystal planes 002 of the insoluble and infusible substrate used in the present invention is 3.6 mm or more, and preferably 3.7 mm or more. When the surface separation is less than 3.6 mm, the surface separation is narrow, and it is difficult to obtain the output characteristics that are the characteristics of the present invention. Although the upper limit is not particularly limited, it is desirable to set the surface interval to 4.5 mm or less, and when it exceeds 4.5 mm, the aromatic polycyclic structure is undeveloped and it becomes difficult to dope lithium. The insoluble infusible substrate of the present invention has an amorphous structure, and the crystallite length in the C-axis direction of the crystal plane 002, which is obtained from the half width of the main peak, is preferably 15 mm or less. The lower limit is preferably 5 mm or more. Since the insoluble and infusible substrate of the present invention has an amorphous structure as described above, lithium can be doped in a large amount and stably, and high output characteristics can be obtained.

  The insoluble and infusible substrate thus obtained can be doped with a larger amount of lithium than graphite and carbon materials, which have been studied as a negative electrode material for a high-power lithium ion battery in the past, for example, 1000 mAh / It is possible to dope lithium exceeding g, and it is a material with a wide range of lithium doping capacity.

  In order to realize a non-aqueous secondary battery having high energy density and high output / high rate charging, it is desired that a large amount of Li ions move at high speed between the negative electrode and the electrolyte. In the case of low output / low rate charge, it is considered that the output / charge proceeds uniformly throughout the negative electrode, but for high output / high rate charge, the lithium ion concentration in the negative electrode and negative electrode active material particles Instantaneous non-uniformity is expected. For the ultra-high power non-aqueous secondary battery, it is necessary to select a negative electrode active material having a wide width capable of doping lithium so as to allow this instantaneous non-uniform lithium ion concentration. In addition, the lithium concentration pre-doped in advance must allow for this non-uniformity, and it is easy to control a negative electrode active material having a wide range of lithium doping capacity. Moreover, in order to promote the movement in the negative electrode active material particle interface, the negative electrode active material particle diameter needs to be sufficiently small. A high electrode density is disadvantageous for lithium transfer from the negative electrode active material particle interface to the electrolyte due to a decrease in the amount of electrolyte retained in the electrode, but the electrode volume is reduced even with the same output characteristics. The suppression is to increase the output density, and it is necessary to obtain a high output under conditions where the electrode density is a certain level or higher.

  The average particle size of the insoluble and infusible substrate in the present invention is 2 μm or less, preferably 1 μm or less. The lower limit is preferably as small as possible, but is 0.05 μm or more practically considering current collection and electrode forming. In order to obtain an insoluble infusible substrate of 2 μm or less, for example, the insoluble infusible substrate is pulverized with a pulverizer such as a ball mill, a jet mill, or a bead mill according to a conventional method until a predetermined particle diameter is obtained. Classify. When the average particle diameter exceeds 2 μm, the output that is the object of the present invention cannot be sufficiently obtained. From the viewpoint of output, it is desirable that the 90% particle size in the particle size distribution of the insoluble and infusible substrate is 10 μm or less, preferably 5 μm or less. These average particle size and particle size can be measured with a commercially available laser diffraction particle size distribution analyzer. The powder shape of the insoluble and infusible substrate in the present invention is not particularly limited, and is appropriately selected from spherical, fibrous, amorphous particles and the like.

  The negative electrode for a non-aqueous secondary battery of the present invention comprises the above insoluble and infusible substrate as a main component, and is molded using a conductive material and a binder as necessary. The type of the binder is not particularly limited, and examples thereof include fluorine resins such as polyvinylidene fluoride and polytetrafluoroethylene, and polyolefins such as fluorine rubber, SBR, acrylic resin, polyethylene, and polypropylene. . The amount of the binder is not particularly limited and is appropriately determined depending on the average particle diameter, shape, and the like of the insoluble and infusible substrate. For example, the amount is about 1 to 30% of the weight of the insoluble and infusible substrate. It is preferable. Further, the type and amount of the conductive material are not particularly limited, but are appropriately determined depending on the average particle diameter, shape, H / C, etc. of the insoluble and infusible substrate. And acetylene black and graphite. The amount of the conductive material is not particularly limited, and is preferably set to a ratio of about 1 to 20% of the weight of the insoluble and infusible substrate, for example. The negative electrode used in the non-aqueous secondary battery of the present invention uses the above-mentioned insoluble and infusible substrate by using a general electrode molding method such as coating molding, press molding, roll molding, etc., using a conductive material and a binder as necessary. Can be manufactured.

The electrode density (electrode mixture layer: not including the current collector) of the negative electrode for a non-aqueous secondary battery of the present invention is appropriately determined in consideration of capacity and output, but is 0.8 g / cm ³ or more. Preferably there is. When the electrode density is less than 0.8 g / cm ³ , the energy density is lowered in a non-aqueous secondary battery using this negative electrode, which is not preferable. The upper limit is not particularly limited, but is 1.8 g / cm ³ or less in view of the true density of the insoluble and infusible substrate.

  The electrode thickness of the negative electrode for a non-aqueous secondary battery according to the present invention (electrode mixture layer thickness: does not include a current collector, or the thickness of one side when formed on both sides of the current collector) takes capacity and output into consideration. Although it is appropriately determined, it is preferably 30 μm or more. When the electrode thickness is less than 30 μm, it is not preferable because in the non-aqueous secondary battery using this negative electrode, the energy density decreases due to the relative increase in the volume ratio of the current collector and the separator. Moreover, although it does not specifically limit about an upper limit, when an output is considered, it is 200 micrometers or less.

  The negative electrode for a non-aqueous secondary battery of the present invention can be formed on a current collector, or an electrode formed into a sheet shape can be bonded to the current collector by pressure bonding or a conductive layer. The material of the current collector is not particularly limited, and copper, iron, stainless steel and the like can be used. As the shape of the current collector, a metal foil or a structure capable of forming an electrode in a metal gap can be used. For example, an expanded metal, a netting material, a punching metal, or the like can be used as the current collector.

In the present invention, 500 mAh / g or more of lithium is supported (pre-doped) in advance on the insoluble and infusible substrate as the negative electrode active material. Regarding the pre-doping amount, the amount of lithium supported on the insoluble and infusible substrate as the negative electrode active material is Cn (mAh), the amount of lithium released from the positive electrode during initial charging and Cd (mAh) is doped, and the negative electrode When the weight of the insoluble infusible substrate is W (g), (Cn + Cp) / W is the pre-doping amount. The pre-doping amount is 500 mAh / g or more, preferably 550 mAh / g or more per weight of the insoluble and infusible substrate of the negative electrode. The upper limit is not particularly limited, but is preferably set to 1300 mAh / g or less in consideration of precipitation of lithium metal. The lithium that can be doped by being released from the positive electrode means the amount of lithium contained in the positive electrode during battery assembly and released during the charging operation and taken into the negative electrode. For example, lithium-containing composite oxides such as LiCoO ₂ , LiNiO ₂ , and LiMn ₂ O ₄ are representative examples of positive electrode materials containing lithium contained in the positive electrode.

  The method for supporting lithium in advance on the negative electrode for a non-aqueous secondary battery of the present invention is not particularly limited in the present invention, but a known method can be used. For example, the negative electrode material of the present invention can be formed electrochemically after being formed into an electrode. In the present invention, the method is not particularly limited. For example, before assembling the battery, an electrochemical system using lithium metal as a counter electrode is assembled and pre-doped in a non-aqueous electrolyte described later, and the negative electrode impregnated with the electrolyte is charged with lithium. The method of bonding a metal is mentioned. In addition, in order to pre-dope lithium after battery assembly, a lithium source such as lithium metal and a negative electrode are electrically contacted by a method such as bonding, and an electrolyte is injected into the battery. It is possible to pre-dope lithium.

The negative electrode for a non-aqueous secondary battery in the present invention thus obtained has a discharge of 30 mAh / g or more per weight of the insoluble infusible substrate when discharged at a current density of 40 A / g per weight of the insoluble infusible substrate. Is possible. The potential range in which the negative electrode operates when discharged at a current density of 40 A / g is 2.0 V vs. Li / Li ⁺ or less is preferable, and 1.0 V vs. more preferably. Li / Li ⁺ or less, and it is preferable that 30 mAh / g can be obtained in this potential range. The open-circuit potential range of the negative electrode is preferably 1.0 V vs. Li / Li ⁺ or less, more preferably 0.5 V vs. Li / Li ⁺ or less is preferable. As for the lower limit of the potential range where the negative electrode operates and the lower limit of the open potential range, of course, 0 V vs. It is more than Li / Li ⁺ .

  For convenience, an activated carbon electrode can be used as a counter electrode for evaluating the output characteristics of the negative electrode. In the examples shown below, the negative electrode for a non-aqueous secondary battery of the present invention is evaluated using an activated carbon electrode as a counter electrode, but the positive electrode of the non-aqueous secondary battery using the negative electrode of the present invention is not limited to this. It is not something.

  The negative electrode for a non-aqueous secondary battery of the present invention is combined with a non-aqueous electrolyte obtained by dissolving a positive electrode, a separator and a lithium salt in a non-aqueous solvent, and the non-aqueous secondary battery using the negative electrode for a non-aqueous secondary battery of the present invention is used. A secondary battery can be configured.

  The positive electrode in the present invention is not particularly limited as long as it can be doped / undoped with lithium, and examples thereof include metal oxides, metal sulfides, lithium composite metal oxides, and conductive polymers. Yes, as lithium composite metal oxide, lithium composite cobalt oxide, lithium composite nickel oxide, lithium composite manganese oxide, lithium composite iron phosphate, or a mixture thereof, and more than one kind of different metal elements in these composite oxides An added system or the like can be used. In order to obtain a non-aqueous secondary battery having a high energy density and high output, which is the object of the present invention, it is preferable to use, for example, an oxide having a small particle size.

The non-aqueous secondary battery of the present invention uses a non-aqueous electrolyte solution in which a lithium salt is dissolved in a non-aqueous solvent. As the non-aqueous electrolyte solution used in the present invention, a non-aqueous electrolyte solution containing a lithium salt can be used. According to the use conditions such as the type of the positive electrode material, the property of the negative electrode material, the charging voltage, etc. It is determined. Examples of the non-aqueous electrolyte containing a lithium salt include lithium salts such as LiPF ₆ , LiBF ₄ , LiClO ₄ , propylene carbonate, ethylene carbonate, diethyl carbonate, dimethyl carbonate, methyl ethyl carbonate, dimethoxyethane, γ-butyrolactone, acetic acid. What was melt | dissolved in the organic solvent which consists of 1 type, or 2 or more types, such as methyl and methyl formate, can be used. The concentration of the electrolytic solution is not particularly limited, but generally about 0.5 to 2 mol / l is practical. As a matter of course, it is preferable to use an electrolytic solution having a water content of 100 ppm or less.

  The separator of the non-aqueous secondary battery in the present invention is not particularly limited, and a polyethylene microporous film, a polypropylene microporous film, or a laminated film of polyethylene and polypropylene, cellulose, glass fiber, polyaramid fiber, polyacrylonitrile fiber, etc. There are woven fabrics, nonwoven fabrics, and the like, which can be appropriately determined according to the purpose and situation.

  The shape of the non-aqueous secondary battery of the present invention is not particularly limited, and can be appropriately determined according to the purpose, such as a coin type, a cylindrical type, a square type, a film type, and the like.

  EXAMPLES Examples will be shown below to further clarify the features of the present invention, but the present invention is not limited to the examples.

  (1) 320 g of the phenolic resin cured body was placed in a stainless steel dish, and this dish was placed in a square furnace (400 × 400 × 400 mm) and subjected to a thermal reaction. The thermal reaction was performed in a nitrogen atmosphere, and the nitrogen flow rate was 5 liters / minute. The thermal reaction was performed at a rate of 1 ° C./minute until the furnace temperature was raised from room temperature to 630 ° C., held at that temperature for 4 hours, then cooled to 60 ° C. by natural cooling, and the dish was removed from the furnace. The insoluble and infusible substrate of the present invention was obtained. The yield was 192g.

(2) The obtained insoluble and infusible substrate was ground to an average particle size of 0.8 μm using a planetary ball mill. Element analysis (measurement machine: PE2400 series II, CHNS / O) manufactured by Perkin Elmer, and specific surface area by BET method (measurement machine: Yuasa Ionics) Measurement of “NOVA1200”). In addition, the crystal structure was analyzed by an XRD (X-ray diffraction) method (measurement machine: fully automatic X-ray diffractometer “MXP ³ ” manufactured by Mac Science Co., Ltd., and generated X-rays are Cu—Kα rays). In the elemental analysis, the atomic ratio of hydrogen atoms / carbon atoms is 0.27, the specific surface area is 570 m ² / g, the interplanar spacing of the crystal plane 002 is 3.97 mm, and the crystal plane 002 plane is in the C-axis direction. It was an insoluble and infusible substrate (hereinafter referred to as PAS) having a crystallite length of 10.2 mm. An X-ray diffraction pattern is shown for material A in FIG.

  (3) Next, 80 parts by weight of the above PAS, 10 parts by weight of conductive material acetylene black, and 10 parts by weight of PVdF (polyvinylidene fluoride) are mixed with 230 parts by weight of NMP (N-methyl-2-pyrrolidone), and a negative electrode mixture slurry Got. This slurry was applied to one side of a 18 μm thick copper foil, dried, and then pressed to obtain an electrode. The electrode density and electrode thickness are shown in Table 1.

(4) The electrode obtained above is used as a working electrode, lithium metal is used as a counter electrode, and a concentration of 1 mol / l is added to a solvent in which ethylene carbonate and methyl ethyl carbonate are mixed at an electrolyte ratio of 3: 7 (volume ratio). An electrochemical cell was prepared in a dry room using a solution in which LiPF ₆ was dissolved. Lithium doping is performed at a current of 60 mA / g per weight of PAS until 1 mV with respect to the lithium potential, and further, a constant voltage of 1 mV is applied against the lithium potential to perform doping of 600 mAh / g per weight of PAS. A negative electrode on which lithium was previously supported was obtained. The negative electrode has a high capacity of 540 mAh / g when a constant voltage of 1 mV is applied to the lithium potential in the above operation for 12 hours and then discharged to 2.5 V at a current of 60 mA / g. Yes.

  (5) For the positive electrode, 93 parts by weight of commercially available activated carbon, 7 parts by weight of conductive material ketjen black and 17 parts by weight of PVdF were mixed with 355 parts by weight of NMP to obtain a positive electrode mixture slurry. A positive electrode mixture slurry was applied to one side of an aluminum foil having a thickness of 30 μm previously coated with a graphite-based conductive paint, dried, and then pressed to obtain an electrode. In this example, activated carbon is used for the positive electrode for the purpose of evaluating a negative electrode having excellent output characteristics. However, in the nonaqueous secondary battery according to claim 5 of the present invention, the positive electrode is not limited to activated carbon.

(6) The negative electrode obtained above and the above-obtained activated carbon electrode having a thickness of 84 μm and a density of 0.60 g / cm ³ are combined as a positive electrode, and ethylene carbonate and methyl ethyl carbonate are used as an electrolyte solution in a ratio of 3: 7 ( An electrochemical cell for negative electrode evaluation was prepared in a dry room by using a solution in which LiPF ₆ was dissolved in a solvent mixed at a volume ratio of 1 mol / l.

  (7) The cell was charged to 4.0 V at a current of 4.8 A / g per weight of PAS, and then discharged to 2.0 V at a current of 95 mA / g. The capacity at this time was 84.9 mAh / g based on the weight of PAS. Subsequently, after the same charging as described above, the output characteristics were confirmed while changing the current density. When discharged at a current of 4.8 A / g, the capacity was 70.8 mAh / g based on the weight of PAS. When discharged at a current of 9.5 A / g, the capacity was 63.6 mAh / g based on the weight of PAS. When discharged at a current of 28.6 A / g, the capacity was 47.1 mAh / g based on the weight of PAS. When discharged at a current of 47.7 A / g, the capacity was 33.1 mAh / g based on the weight of PAS.

(8) The AC resistance of the cell was measured at 0.1 Hz and found to be 9.5 Ω · cm ² per unit area. Table 1 summarizes the material and particle size used for the negative electrode material, the amount of lithium previously supported, the electrode properties, the output characteristics, and the AC resistance for Example 1.

(1) An electrode obtained by the same method as in Example 1 was used as a working electrode, lithium metal was used as a counter electrode, and 1 mol of a solvent in which ethylene carbonate and methyl ethyl carbonate were mixed at an electrolyte ratio of 3: 7 (volume ratio). An electrochemical cell was prepared in a dry room using a solution of LiPF ₆ dissolved to a concentration of 1 / l. Lithium doping is performed at a current of 80 mA / g per weight of PAS until 1 mV with respect to the lithium potential, and a constant voltage of 1 mV is applied against the lithium potential to perform doping of 800 mAh / g per weight of PAS. A negative electrode on which lithium was previously supported was obtained.

(2) The negative electrode obtained above and an activated carbon electrode having a thickness of 86 μm and a density of 0.61 g / cm ³ obtained by the same method as in Example 1 were used as the positive electrode, and ethylene carbonate and methyl ethyl carbonate as electrolytes. An electrochemical cell for negative electrode evaluation was prepared in a dry room using a solution in which LiPF ₆ was dissolved at a concentration of 1 mol / l in a solvent mixed with 3: 7 (volume ratio).

  (3) After charging to 4.0 V at a current of 4.8 A / g per weight of PAS, the battery was discharged to 2.0 V at a current of 95 mA / g. The capacity at this time was 90.7 mAh / g based on the weight of PAS. Subsequently, after the same charging as described above, the output characteristics were confirmed while changing the current density. When discharged at a current of 4.8 A / g, the capacity was 76.2 mAh / g based on the weight of PAS. When discharged at a current of 9.5 A / g, the capacity was 68.8 mAh / g based on the weight of PAS. When discharged at a current of 28.6 A / g, the capacity was 53.0 mAh / g based on the weight of PAS. When discharged at a current of 47.7 A / g, the capacity was 39.5 mAh / g based on the weight of PAS.

(4) The AC resistance of the cell was measured at 0.1 Hz and found to be 8.5 Ω · cm ² per unit area. Table 1 summarizes the material and particle size used for the negative electrode material, the amount of lithium previously supported, the electrode properties, the output characteristics, and the AC resistance for Example 2.

(1) An electrode obtained by the same method as in Example 1 was used as a working electrode, lithium metal was used as a counter electrode, and 1 mol of a solvent in which ethylene carbonate and methyl ethyl carbonate were mixed at an electrolyte ratio of 3: 7 (volume ratio). An electrochemical cell was prepared in a dry room using a solution of LiPF ₆ dissolved to a concentration of 1 / l. Lithium doping is performed at a current of 100 mA / g per weight of PAS until 1 mV with respect to the lithium potential, and further, a constant voltage of 1 mV is applied against the lithium potential to perform doping of 1000 mAh / g per weight of PAS. A negative electrode on which lithium was previously supported was obtained.

(2) The negative electrode obtained above and an activated carbon electrode having a thickness of 86 μm and a density of 0.59 g / cm ³ obtained by the same method as in Example 1 were combined as a positive electrode, and ethylene carbonate and methyl ethyl carbonate were used as electrolytes. An electrochemical cell for negative electrode evaluation was prepared in a dry room using a solution prepared by dissolving LiPF ₆ at a concentration of 1 mol / l in a solvent prepared by mixing 7 and 7 in a volume ratio.

  (3) After charging to 4.0 V at a current of 4.5 A / g per weight of PAS, the battery was discharged to 2.0 V at a current of 90 mA / g. The capacity at this time was 85.7 mAh / g based on the weight of PAS. Subsequently, after the same charging as described above, the output characteristics were confirmed while changing the current density. When discharged at a current of 4.5 A / g, the capacity was 70.8 mAh / g based on the weight of PAS. When discharged at a current of 9.0 A / g, the capacity was 63.4 mAh / g based on the weight of PAS. When discharged at a current of 26.9 A / g, the capacity was 48.3 mAh / g based on the weight of PAS. When discharged at a current of 44.8 A / g, the capacity was 36.1 mAh / g based on the weight of PAS.

(4) The AC resistance of the cell was measured at 0.1 Hz and found to be 8.5 Ω · cm ² per unit area. Table 1 summarizes the material and particle size used for the negative electrode material, the amount of lithium carried in advance, electrode physical properties, output characteristics, and AC resistance for Example 3.
(Comparative Example 1)

(1) An electrode obtained by the same method as in Example 1 was used as a working electrode, lithium metal was used as a counter electrode, and 1 mol of a solvent in which ethylene carbonate and methyl ethyl carbonate were mixed at an electrolyte ratio of 3: 7 (volume ratio). An electrochemical cell was prepared in a dry room using a solution of LiPF ₆ dissolved to a concentration of 1 / l. Lithium doping is performed at a current of 40 mA / g per weight of PAS until 1 mV with respect to the lithium potential, and further, a constant voltage of 1 mV is applied to the lithium potential to perform doping of 400 mAh / g per weight of PAS. A negative electrode on which lithium was previously supported was obtained.

(2) The negative electrode obtained above and an activated carbon electrode having a thickness of 85 μm and a density of 0.58 g / cm ³ obtained by the same method as in Example 1 were combined as a positive electrode, and ethylene carbonate and methyl ethyl carbonate were used as electrolytes. An electrochemical cell for negative electrode evaluation was prepared in a dry room using a solution prepared by dissolving LiPF ₆ at a concentration of 1 mol / l in a solvent prepared by mixing 7 and 7 in a volume ratio.

  (3) After charging to 4.0 V at a current of 4.1 A / g per weight of PAS, the battery was discharged to 2.0 V at a current of 81 mA / g. The capacity at this time was 69.1 mAh / g based on the weight of PAS. Subsequently, after the same charging as described above, the output characteristics were confirmed while changing the current density. When discharged at a current of 4.1 A / g, the capacity was 46.9 mAh / g based on the weight of PAS. When discharged at a current of 8.1 A / g, the capacity was 39.6 mAh / g based on the weight of PAS. When discharged at a current of 24.4 A / g, the capacity was 21.7 mAh / g based on the weight of PAS. When discharged at a current of 40.6 A / g, the capacity was 9.9 mAh / g based on the weight of PAS.

(4) The AC resistance of the cell was measured at 0.1 Hz and found to be 14.6 Ω · cm ² per unit area. About the said comparative example 1, the material and particle size which were used for the negative electrode material, the amount of lithium carried beforehand, an electrode physical property, an output characteristic, and alternating current resistance are put together in Table 1.
(Comparative Example 2)

(1) The insoluble and infusible substrate obtained by the same method as in Example 1 was pulverized to an average particle size of 4.3 μm using a planetary ball mill. About the obtained insoluble and infusible substrate, elemental analysis (measurement machine: elemental analyzer “PE2400 series II, CHNS / O” manufactured by PerkinElmer Co., Ltd.) and specific surface area (measurement machine: Yuasa Ionics Co., Ltd.) "NOVA1200") was measured. In addition, the crystal structure was analyzed by an XRD (X-ray diffraction) method (measurement machine: fully automatic X-ray diffractometer “MXP ³ ” manufactured by Mac Science Co., Ltd., and generated X-rays are Cu—Kα rays). Elemental analysis shows an insoluble infusible substrate (PAS) having a hydrogen atom / carbon atom atomic ratio of 0.27, a specific surface area of 321 m ² / g, and a crystal plane 002 plane spacing of 3.77 mm. This is an insoluble infusible substrate (hereinafter referred to as PAS) having a crystallite length of 12.7 mm in the C-axis direction of the crystal plane 002. The X-ray diffraction pattern is shown in Material B of FIG.

  (2) Next, 80 parts by weight of the above PAS, 10 parts by weight of conductive material acetylene black and 10 parts by weight of PVdF were mixed with 230 parts by weight of NMP to obtain a negative electrode mixture slurry. This slurry was applied to one side of a 18 μm thick copper foil, dried, and then pressed to obtain an electrode. The electrode density and electrode thickness are shown in Table 1.

(3) The electrode obtained above is used as a working electrode, lithium metal is used as a counter electrode, and a concentration of 1 mol / l is added to a solvent in which ethylene carbonate and methyl ethyl carbonate are mixed at an electrolyte ratio of 3: 7 (volume ratio). An electrochemical cell was prepared in a dry room using a solution in which LiPF ₆ was dissolved. Lithium doping is performed at a current of 60 mA / g per weight of PAS until 1 mV with respect to the lithium potential, and further, a constant voltage of 1 mV is applied against the lithium potential to perform doping of 600 mAh / g per weight of PAS. A negative electrode on which lithium was previously supported was obtained. The negative electrode has a high capacity of 490 mAh / g when a constant voltage of 1 mV is applied to the lithium potential in the above operation for 12 hours and then discharged to 2.5 V at a current of 60 mA / g. Yes.

(4) The negative electrode obtained above and an activated carbon electrode having a thickness of 82 μm and a density of 0.59 g / cm ³ obtained by the same method as in Example 1 were combined as a positive electrode, and ethylene carbonate and methyl ethyl carbonate were used as electrolytes. An electrochemical cell for negative electrode evaluation was prepared in a dry room using a solution prepared by dissolving LiPF ₆ at a concentration of 1 mol / l in a solvent prepared by mixing 7 and 7 in a volume ratio.

  (5) After charging to 4.0 V at a current of 4.0 A / g per weight of PAS, the battery was discharged to 2.0 V at a current of 79 mA / g. The capacity at this time was 71.9 mAh / g based on the weight of PAS. Subsequently, after the same charging as described above, the output characteristics were confirmed while changing the current density. When discharged at a current of 4.0 A / g, the capacity was 54.9 mAh / g based on the weight of PAS. When discharged at a current of 7.9 A / g, the capacity was 47.2 mAh / g based on the weight of PAS. When discharged at a current of 23.7 A / g, the capacity was 30.4 mAh / g based on the weight of PAS. When discharged at a current of 39.5 A / g, the capacity was 14.8 mAh / g based on the weight of PAS.

(6) The AC resistance of the cell was measured at 0.1 Hz and found to be 15.3 Ω · cm ² per unit area. About the said comparative example 2, the material and particle size which were used for the negative electrode material, the amount of lithium carried beforehand, an electrode physical property, an output characteristic, and alternating current resistance are put together in Table 1.
(Comparative Example 3)

(1) An electrode obtained by the same method as in Comparative Example 2 was used as a working electrode, lithium metal was used as a counter electrode, and a solvent in which ethylene carbonate and methyl ethyl carbonate were mixed as an electrolyte in a ratio of 3: 7 (volume ratio). An electrochemical cell was prepared in a dry room using a solution in which LiPF ₆ was dissolved at a concentration of 1 mol / l. Lithium doping is performed at a current of 80 mA / g per weight of PAS until 1 mV with respect to the lithium potential, and a constant voltage of 1 mV is applied against the lithium potential to perform doping of 800 mAh / g per weight of PAS. A negative electrode on which lithium was previously supported was obtained.

(2) The negative electrode obtained above and an activated carbon electrode having a thickness of 83 μm and a density of 0.59 g / cm ³ obtained by the same method as in Example 1 were combined as a positive electrode, and ethylene carbonate and methyl ethyl carbonate were used as electrolytes. An electrochemical cell for negative electrode evaluation was prepared in a dry room using a solution prepared by dissolving LiPF ₆ at a concentration of 1 mol / l in a solvent prepared by mixing 7 and 7 in a volume ratio.

  (3) After charging to 4.0 V at a current of 4.4 A / g per weight of PAS, the battery was discharged to 2.0 V at a current of 89 mA / g. The capacity at this time was 87.8 mAh / g based on the weight of PAS. Subsequently, after the same charging as described above, the output characteristics were confirmed while changing the current density. When discharged at a current of 4.4 A / g, the capacity was 67.2 mAh / g based on the weight of PAS. When discharged at a current of 8.9 A / g, the capacity was 56.8 mAh / g based on the weight of PAS. When discharged at a current of 26.6 A / g, the capacity was 36.2 mAh / g based on the weight of PAS. When discharged at a current of 44.3 A / g, the capacity was 17.7 mAh / g based on the weight of PAS.

(4) The AC resistance of the cell was measured at 0.1 Hz and found to be 15.0 Ω · cm ² per unit area. About the said comparative example 3, the material and particle size which were used for the negative electrode material, the amount of lithium carried beforehand, an electrode physical property, an output characteristic, and alternating current resistance are put together in Table 1.
(Comparative Example 4)

(1) An electrode obtained by the same method as in Comparative Example 2 was used as a working electrode, lithium metal was used as a counter electrode, and a solvent in which ethylene carbonate and methyl ethyl carbonate were mixed as an electrolyte in a ratio of 3: 7 (volume ratio). An electrochemical cell was prepared in a dry room using a solution in which LiPF ₆ was dissolved at a concentration of 1 mol / l. Lithium doping is performed at a current of 100 mA / g per weight of PAS until 1 mV with respect to the lithium potential, and further, a constant voltage of 1 mV is applied against the lithium potential to perform doping of 1000 mAh / g per weight of PAS. A negative electrode on which lithium was previously supported was obtained.

(2) The negative electrode obtained above and an activated carbon electrode having a thickness of 86 μm and a density of 0.60 g / cm ³ obtained by the same method as in Example 1 were combined as the positive electrode, and ethylene carbonate and methyl ethyl carbonate were used as the electrolyte. An electrochemical cell for negative electrode evaluation was prepared in a dry room using a solution prepared by dissolving LiPF ₆ at a concentration of 1 mol / l in a solvent prepared by mixing 7 and 7 in a volume ratio.

  (3) After charging to 4.0 V at a current of 3.9 A / g per weight of PAS, the battery was discharged to 2.0 V at a current of 78 mA / g. The capacity at this time was 80.2 mAh / g based on the weight of PAS. Subsequently, after the same charging as described above, the output characteristics were confirmed while changing the current density. When discharged at a current of 3.9 A / g, the capacity was 64.2 mAh / g based on the weight of PAS. When discharged at a current of 7.8 A / g, the capacity was 55.6 mAh / g based on the weight of PAS. When discharged at a current of 23.5 A / g, the capacity was 38.7 mAh / g based on the weight of PAS. When discharged at a current of 39.2 A / g, the capacity was 22.9 mAh / g based on the weight of PAS.

(4) The AC resistance of the cell was measured at 0.1 Hz and found to be 12.9 Ω · cm ² per unit area. About the said comparative example 4, the material and particle size which were used for the negative electrode material, the amount of lithium carried beforehand, an electrode physical property, an output characteristic, and alternating current resistance are put together in Table 1.
(Comparative Example 5)

  (1) 600 g of an isotropic pitch having a softening point of 270 ° C. was placed in a stainless steel dish, and this dish was placed in a square furnace (400 × 400 × 400 mm) and subjected to a thermal reaction. The thermal reaction was performed in a nitrogen atmosphere, and the nitrogen flow rate was 10 liters / minute. The thermal reaction is performed at a rate of 2 ° C./minute until the furnace temperature reaches from room temperature to 400 ° C., and then at a rate of 1 ° C./minute, the furnace temperature is increased from room temperature to 665 ° C. After maintaining at the same temperature for 12 hours, the plate was cooled to 60 ° C. by natural cooling, and the dish was taken out of the furnace. The obtained product did not retain the shape of the raw material, and was an amorphous insoluble and infusible substrate. The yield was 485g.

(2) The insoluble and infusible substrate obtained above was pulverized to an average particle size of 0.9 μm using a planetary ball mill to obtain a negative electrode active material. About the obtained negative electrode material, elemental analysis (measurement machine: PerkinElmer element analyzer “PE2400 series II, CHNS / O) and BET specific surface area (measurement machine: Yuasa Ionics“ NOVA1200 ”) ) Was measured. In addition, the crystal structure was analyzed by an XRD (X-ray diffraction) method (measurement machine: fully automatic X-ray diffractometer “MXP ³ ” manufactured by Mac Science Co., Ltd., and generated X-rays are Cu—Kα rays). Elemental analysis is an insoluble infusible substrate (hereinafter referred to as PAHs) having a hydrogen atom / carbon atom atomic ratio of 0.19, a specific surface area of 98 m ² / g, and a crystal plane 002 plane spacing of 3.44 mm. And the crystallite length in the C-axis direction of the crystal plane 002 was 18.2 mm. The X-ray diffraction pattern is shown for material C in FIG.

  (3) Next, 80 parts by weight of the above PAHs, 10 parts by weight of conductive material acetylene black and 10 parts by weight of PVdF were mixed with 205 parts by weight of NMP to obtain a negative electrode mixture slurry. This slurry was applied to one side of a 18 μm thick copper foil, dried, and then pressed to obtain an electrode. The electrode density and electrode thickness are shown in Table 1.

(4) The electrode obtained above is used as a working electrode, lithium metal is used as a counter electrode, and a concentration of 1 mol / l is added to a solvent in which ethylene carbonate and methyl ethyl carbonate are mixed at an electrolyte ratio of 3: 7 (volume ratio). An electrochemical cell was prepared in a dry room using a solution in which LiPF ₆ was dissolved. Lithium doping is performed at a current of 60 mA / g per weight of PAHs until 1 mV with respect to the lithium potential, and further, a constant voltage of 1 mV is applied to the lithium potential to perform doping of 600 mAh / g per weight of PAHs, A negative electrode on which lithium was previously supported was obtained. The negative electrode has a high capacity of 753 mAh / g when a constant voltage of 1 mV is applied to the lithium potential in the above operation for 12 hours and then discharged to 2.5 V at a current of 60 mA / g. Yes.

(5) A negative electrode obtained above and an activated carbon electrode having a thickness of 87 μm and a density of 0.60 g / cm ³ obtained by the same method as in Example 1 are combined as a positive electrode, and ethylene carbonate and methyl ethyl carbonate are used as electrolytes. An electrochemical cell for negative electrode evaluation was prepared in a dry room using a solution prepared by dissolving LiPF ₆ at a concentration of 1 mol / l in a solvent prepared by mixing 7 and 7 in a volume ratio.

  (6) After charging to 4.0 V at a current of 3.23 A / g per weight of PAHs, it was discharged to 2.0 V at a current of 65 mA / g. The capacity at this time was 61.1 mAh / g based on the weight of PAS. Subsequently, after the same charging as described above, the output characteristics were confirmed while changing the current density. When discharged at a current of 3.2 A / g, the capacity was 42.2 mAh / g based on the weight of PAHs. When discharged at a current of 6.5 A / g, the capacity was 35.1 mAh / g based on the weight of PAHs. When discharged at a current of 19.4 A / g, the capacity was 21.2 mAh / g based on the weight of PAHs. When discharged at a current of 32.3 A / g, the capacity was 8.4 mAh / g based on the weight of PAHs.

(7) The AC resistance of the cell was measured at 0.1 Hz and found to be 17.8 Ω · cm ² per unit area. About the said comparative example 5, the material and particle size which were used for the negative electrode material, the amount of lithium carried beforehand, an electrode physical property, an output characteristic, and alternating current resistance are put together in Table 1.

  The discharge current per unit weight (current density) of the insoluble infusible substrate according to Examples 1 to 3 and Comparative Examples 1 to 5 and the discharge capacity per unit weight of the insoluble infusible substrate It is shown in 2. In the case where the average particle diameter of the insoluble infusible substrate of the present invention is 2.0 μm or less and lithium of 500 mAh / g or more per weight of the insoluble infusible substrate is previously supported, a hatched line in FIG. A capacity of 30 mAh / g or more per weight of the insoluble infusible substrate can be obtained at a discharge current (current density) of 40 A / g or more per weight of the insoluble infusible substrate as shown in FIG. It is clear that the fusible substrate can be discharged even at a very high current density of 40 A / g or more.

  As a use of the negative electrode for non-aqueous secondary batteries of this invention, the use of output electrical storage devices, such as a hybrid electric vehicle and a fuel cell electric vehicle, etc. are mentioned, for example. In particular, the negative electrode for a non-aqueous secondary battery can achieve both high energy density and unprecedented high output, and contributes to the reduction in size and weight of the output power storage device.

It is an X-ray diffraction pattern of each insoluble and infusible substrate used in Examples and Comparative Examples of the present invention. The material A in the figure was used in Examples 1 to 3 and Comparative Example 1, the material B in the figure was used in Comparative Examples 2 to 4, and the material C in the figure was used in Comparative Example 5. It is the figure explaining the discharge current (current density) per weight of the insoluble infusible substrate according to Examples 1 to 3 and Comparative Examples 1 to 5, and the discharge capacity per weight of the insoluble infusible substrate.

Claims (5)

  A negative electrode for a non-aqueous secondary battery whose main component is an insoluble infusible substrate having a hydrogen atom / carbon atom ratio of 0.60 to 0.05 and an interplanar spacing of crystal plane 002 of 3.6 mm or more In which an average particle diameter of the insoluble and infusible substrate is 2.0 μm or less and lithium of 500 mAh / g or more per weight of the insoluble and infusible substrate is previously supported. Negative electrode. The negative electrode for a non-aqueous secondary battery according to claim 1, wherein the negative electrode for the non-aqueous secondary battery has an electrode density of 0.8 g / cm ³ or more.   The negative electrode for a non-aqueous secondary battery according to claim 1 or 2, wherein the negative electrode for the non-aqueous secondary battery has an electrode thickness of 30 µm or more.   In the negative electrode for a non-aqueous secondary battery, when discharged at a current density of 40 A / g per weight of the insoluble infusible substrate, discharge of 30 mAh / g or more per weight of the insoluble infusible substrate is possible. The negative electrode for a non-aqueous secondary battery according to any one of claims 1 to 3. 5. A non-aqueous secondary battery using the negative electrode according to claim 1, wherein the non-aqueous secondary battery includes a non-aqueous electrolyte solution in which a positive electrode, a negative electrode, a separator, and a lithium salt are dissolved in a non-aqueous solvent. battery.

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