JPS62122066A - Nonaqueous solvent battery - Google Patents

Abstract

PURPOSE:To increase charge-discharge performance and storage stability by forming a negative electrode with carbon material obtained by carbonizing a compound such as organic polymer compond. CONSTITUTION:Carbon material for negative electrode is obtained by carbonizing at least one compound selected from a group comprising organic polymer compound, condensation polycyclic hydrocarbon compound, and polycyclic heterocyclic compound, and has a pseudographite structure simultaneously satisfying the following conditions. The first condition is that atomic ratio of H/C obtained by elementary analysis is less than 0.15, preferably less than 0.07. The second is that the spacing (d002) of (002) crystal face obtained by X-ray wide angle diffraction is 3.37Angstrom or more, preferably 3.41-3.70Angstrom . The third is that the size of crystallite (Lc) in C crystal orientation obtained by X-ray wide angle diffraction is 150Angstrom or less, preferably 10-70Angstrom .

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a non-aqueous solvent secondary battery, and more specifically, a non-aqueous solvent secondary battery that suppresses self-discharge and has good charge-discharge cycle characteristics;
The present invention also relates to a non-aqueous solvent secondary battery with excellent storage stability.

[Prior Art] In recent years, a type of conductive polymer has been used as a negative electrode material as a secondary battery that is small, lightweight, and has a high energy density.

A combination with an electrolyte solution in which alkali metal ions such as lithium ions and sodium ions are dissolved is attracting attention. This type of secondary battery electrochemically dopes/dedopes (or intercalates/dintercalates) the metal ions mentioned above to the negative electrode.
(late/deintercalate) and utilizes this doping/dedoping phenomenon as a charging/discharging process, similar to conventional secondary batteries that use the alkali metal itself as the negative electrode.

This has the advantage that internal short circuits and significant decreases in charge/discharge efficiency caused by dendrite-like precipitation of alkali metals during charging can be avoided.

Conventionally, this type of secondary battery has been used, for example, in Japanese Patent Application Laid-Open No.
A combination of a negative electrode made of polyacetylene and lithium ions, as described in Japanese Patent No. 1384139, is known. In addition to the above-mentioned polyacetylene, examples of conductive polymers that can be used as negative electrode materials include poly(p-phenylene), polypyrrole, polythenylene, polyaniline, poly(p-phenylene sulfite), and poly(p-phenylene oxide). Examples include linear polymeric compounds having conjugated double bonds such as.

Such conductive polymers are lightweight and doped with alkali metal ions such as lithium ions.
Since the dedoping potential is approximately the same as the charge/discharge potential when an alkali metal is used as the negative electrode, it has the advantage of high energy density per unit weight when incorporated into a secondary battery.

However, on the other hand, the above-mentioned conductive polymers are chemically unstable in a state doped with alkali metal ions, that is, in a charged state, and may react with solvents or
Alternatively, since the battery itself decomposes, there is a problem that not only the self-discharge as a secondary battery becomes extremely large, but also the charging/discharging cycle characteristics are deteriorated.

On the other hand, graphite, which has a structure in which conjugated double bonds are spread two-dimensionally, was used as the carbonaceous material constituting the negative electrode, and alkali metal ions were intercalated between the graphite layers by electrochemical reduction. A secondary battery using a graphite compound as a negative electrode active material has been reported. However, in such secondary batteries, the alkali metal-graphite intercalation compound formed by charging is chemically unstable and reacts with the solvent accompanied by destruction of the graphite structure, resulting in poor storage stability. Moreover, there is a disadvantage that it causes a decrease in charge/discharge efficiency and a deterioration in cycle characteristics.

Further, a secondary battery has been proposed in which a carbonaceous material constituting the negative electrode is obtained by carbonizing an organic polymer compound such as phenol resin, polyacrylonitrile, or cellulose.

For example, JP-A-58-209884 discloses a carbonaceous material obtained by heat-treating an aromatic condensation polymer and having an atomic ratio of hydrogen/carbon in the range of 0.15 to 0.33. A secondary battery using this as a negative electrode has been disclosed.

Although such a secondary battery can obtain higher output than the conventional secondary battery using conductive polymer or graphite as the negative electrode, the negative electrode irreversibly reacts with the electrolyte solvent in the charged state, and as a result, The reality is that no improvements have been made in terms of increasing self-discharge and deteriorating cycle characteristics.

[Problem to be Solved by the Invention 1] As described above, negative electrode materials that utilize the doping/dedoping (or intercalation/dintercalation) phenomenon of alkali metal ions may However, the problem of increased self-discharge and short cycle life remains.

The present invention aims to solve these conventional problems and provide a non-aqueous solvent secondary battery that has little self-discharge, good charge-discharge cycle characteristics, and excellent storage stability.

[Means for Solving the Problems] In order to achieve the above object, the present inventor has conducted intensive research focusing on negative electrode materials for non-aqueous solvent secondary batteries, and as a result, has found a solution that simultaneously satisfies the conditions described below. The inventors have now completed the present invention by discovering that a non-aqueous solvent secondary battery with excellent properties can be obtained when the negative electrode is made of a carbonaceous material.

That is, the non-aqueous solvent secondary battery of the present invention includes a rechargeable positive electrode, an electrolytic solution formed by dissolving an electrolyte in a non-aqueous solvent, and a rechargeable negative electrode. wherein the negative electrodes are obtained by carbonizing at least one compound selected from the group consisting of organic polymer compounds, fused polycyclic hydrocarbon compounds, and polycyclic heterocyclic compounds, and / carbon atomic ratio is less than 0.15, the interplanar spacing of the (002) plane determined by X-ray wide-angle diffraction is 3.37 Å or more, and the crystallite size in the C-axis direction is 150 Å.
It is characterized by being made of a carbonaceous material having a pseudographite structure of λ or less.

[Specific Description] In the nonaqueous solvent secondary battery of the present invention, organic polymer compounds, fused polycyclic hydrocarbon compounds, and polycyclic heterocyclic compounds are used as starting materials for obtaining the carbonaceous material constituting the negative electrode. At least one compound selected from the group consisting of:

Examples of organic polymer compounds include cellulose resin;
Phenol resins; acrylic resins such as polyacrylonitrile and poly(α-halogen acrylonitrile); halogenated vinyl resins such as polyvinyl chloride, polyvinylidene chloride, and polychlorinated vinyl chloride; polyamide-imide resins;
Polyamide resin: Any organic polymer compound such as conjugated resin such as polyacetylene and poly(p-phenylene) can be used, and linear novolak resin is particularly preferred.

Next, the fused polycyclic hydrocarbon compound is a fused polycyclic hydrocarbon compound formed by two or more monocyclic hydrocarbon compounds having three or more members fused together, and derivatives thereof, such as naphthalene, phenanthrene, anthracene, triphenylene. , pyrene, chrysene, naphthacene, picene, perylene, pentaphene, pentacene, etc., and examples of derivatives include carboxylic acids, carboxylic acid anhydrides, and carboxylic acid imides thereof. Furthermore, various pitches containing mixtures of the above-mentioned compounds as main components may be used.

Furthermore, polycyclic heterocyclic compounds include at least two or more heteromonocyclic compounds having three or more members bonded to each other, or one
A fused heterocyclic compound formed by combining three or more three-membered rings or more monocyclic hydrocarbon compounds and derivatives thereof, such as:
Examples include indole, isoindole, quinoline, inquinoline, quinoxaline, phthalazine, carbazole, acridine, phenazine, phenanthrene, and derivatives thereof include carboxylic acids, carboxylic acid anhydrides, carboxylic acid imides, and the like. Furthermore, 1,2,4,5-tetracarboxylic acid of benzene, its dianhydride, its diimide, etc. may be used.

The carbonaceous material of the present invention is obtained by carbonizing each compound listed above, and has a pseudographite structure that simultaneously satisfies each of the following conditions.

That is, first, the hydrogen/carbon atomic ratio determined by elemental analysis is less than 0.15, preferably less than 0.10, and more preferably less than 0.07.

Secondly, the interplanar spacing (dQQ2) of the (002) plane determined by wide-angle X-ray diffraction is 3.37A or more, preferably 3.37A or more.
．． The thickness is 39 Å or more and 3.75 Å or less, more preferably 3.41 Å or more and 3.70 Å or less.

Thirdly, the crystallite size (Lc) in the C-axis direction, similarly determined by wide-angle X-ray diffraction, is 150 Å or less, preferably 8 Å or more and 100 Å or less, and more preferably IOA or more and 70 or less.

The carbonaceous material of the present invention can be obtained by carbonizing each of the above-mentioned compounds, and the process is as follows, taking as an example the case where the starting material is a condensed polycyclic hydrocarbon compound. it is conceivable that.

That is, when thermal energy greater than the bond dissociation energy between the skeletal carbon and the hydrogen bonded thereto or the substituent is applied to the starting material by heating, carbon radicals are generated mainly through homolytic cleavage. Carbon radicals bond to each other in a chain, cyclize, increase the molecular weight, develop a polycyclic aromatic plane, and sequentially carbonize. At the initial stage of carbonization, for example, benzene rings form a one-dimensional graphite in which benzene rings are bonded one-dimensionally, then benzene rings begin to bond two-dimensionally, and the polycyclic aromatic planes gradually expand and begin to stack on each other. Two-dimensional graphite is produced.

As carbonization progresses further, the benzene rings become more two-dimensionally bonded, the polycyclic aromatic planes expand sufficiently, and are regularly stacked on each other, eventually asymptotic to normal graphite. In the present invention, the structure up to this graphite is referred to as a pseudographite structure.

The pseudographite structure referred to in the present invention is quantified using X-ray wide-angle diffraction. Normal graphite has a structure near 2θ = 28" (002).
It shows a sharp diffraction peak in the plane.

The one-dimensional graphite formed in the initial stage of carbonization in the present invention does not exhibit any diffraction peak corresponding to the (002) plane, or exhibits a very broad diffraction peak with weak intensity.

Next, the polycyclic aromatic plane expands two-dimensionally to some extent,
As they begin to be stacked on each other, the diffraction peak corresponding to the (002) plane gradually becomes sharper and its intensity increases. The pseudographite structure that characterizes the carbonaceous material of the present invention is quantified as having a (002) interplanar spacing (do02) of 3.37A or more, and a crystallite size (Lc) in the C-axis direction of 150λ or less. . The present invention also includes cases where no diffraction peak corresponding to the (002) plane is observed.

If the carbonaceous material used does not satisfy any one of the three essential requirements above, that is, the hydrogen/carbon atomic ratio is 0.15 or more, or the (002) plane determined by wide-angle X-ray diffraction The interplanar spacing do02 is less than 3.37, or the crystallite size Lc in the C-axis direction is 1
If the number of people exceeds 50, in a secondary battery obtained by using such a carbonaceous material for the negative electrode, the charging/discharging overvoltage on the negative electrode side will increase, and gas may be generated from the electrode during charging.
There arise disadvantages such as poor storage stability in a charged state and deterioration of charge/discharge cycle characteristics.

In addition to the above three conditions, the carbonaceous material used in the present invention desirably satisfies the following conditions: pseudographite structure quantified using X-ray wide-angle diffraction. , the crystallite size L in the a-axis direction
a is preferably 10 Å or more, more preferably 15 Å or more and 150 Å or less, particularly preferably 19 Å or more and 70 Å or less.

In addition, the distance gao (=2dllO), which is twice the interplanar spacing d110 of the (110) plane, also found by X-ray wide-angle diffraction, is
The thickness is preferably 2.38 Å or more and 2.47 Å or less, more preferably 2.39 Å or more and 2.46 Å or less.

Furthermore, the line vA (Δ
Hpp) preferably has one or more signals that are greater than or equal to 20 Gauss, or the peak-to-peak linewidth (ΔHp
Either p) has no signal that is less than 20 Gauss. More preferably, the peak-to-peak line @ (ΔHpp) obtained from the -order differential absorption curve of the electron spin resonance spectrum (measured at 23° C.) has one or more signals of 50 Gauss or more, or either have no signal with a linewidth between them (ΔHpp) of less than 50 Gauss.

The above carbonaceous materials are identified by the hydrogen/carbon atomic ratio determined from elemental analysis as described above, but it is possible that other atoms, such as nitrogen, oxygen, halogen, etc., may be present in small proportions. .

In the present invention, the carbonaceous material constituting the negative electrode can be obtained by carbonizing each of the above-mentioned compounds, specifically by firing them under vacuum or under a flow of inert gas (N2, Ar, etc.). Since this carbonization temperature is closely related to the above hydrogen/carbon atomic ratio, it is necessary to set this atomic ratio to be less than 0.15. The carbonization temperature varies depending on the type of compound used as a starting material, but is usually 50°C.
It is preferable that it is 0-3000 degreeC.

Among the compounds listed above, polyacrylonitrile, pitch, etc. may be subjected to flameproofing treatment or infusibility treatment by heating in an active atmosphere such as air at 200 to 400°C prior to carbonization. preferable.

Furthermore, after completing the carbonization step, the obtained carbonaceous material can be activated by heating in an atmosphere of oxidizing gas such as water or carbon dioxide to increase its specific surface area.

The positive electrode material in the non-aqueous solvent secondary battery of the present invention is not particularly limited, and includes, for example, metal chalcogen compounds that release or capture alkali metal cations such as lithium ions during charging and discharging reactions;
Similarly to the negative electrode described above, a carbonaceous material having a specific hydrogen/carbon atomic ratio is preferable.

First, specific examples of metal chalcogen compounds used as constituent materials of the positive electrode include Or30B and V2O5.

Oxides such as V6O13, LiCoO2, MoO3, WO2; TiS2°V2S5. 'MoS2. Mo5
3. CuS, Fe□, 25VO, 75S2゜Cr0
．． 25V0.75S2. Cr0.5V0.5S21N
a0. Sulfides such as lCr52; N1PS3. Fe
Phosphorus-sulfur compounds such as PS3; VSe2. NbS
Examples include selenides such as e3, especially TiS2
．． MoS2. V2O5 is preferred.

It is preferable to use such a metal chalcogen compound as a positive electrode from the viewpoint of obtaining a highly reliable secondary battery with a large capacity.

On the other hand, the carbonaceous material used as the constituent material of the positive electrode is selected from the group consisting of organic polymer compounds, condensed polycyclic hydrocarbon compounds, and polycyclic heterocyclic compounds, similar to the carbonaceous material constituting the negative electrode. It is obtained by carbonizing at least one type of compound, and the atomic ratio of hydrogen/carbon is 0.10 or more and 0.70 or less, preferably 0.10 or more and 0.70 or less.
．． 60 or less, more preferably 0.10 or more and 0.50 or less. If the hydrogen/carbon atomic ratio exceeds the above range, it may lead to deterioration of battery characteristics, such as an increase in overvoltage during charging and discharging on the positive electrode side, and low charge efficiency and the inability to achieve stable charge/discharge cycles. .

In addition, when using such a carbonaceous material as a positive electrode material, the hydrogen/carbon atomic ratio of the carbonaceous material constituting the positive electrode is larger than the hydrogen/carbon atomic ratio of the carbonaceous material constituting the negative electrode. It is preferable for the battery characteristics to be further improved.

Furthermore, the carbonaceous material preferably has a pseudographite structure that satisfies the following conditions. That is, the carbonaceous material used for the positive electrode is first determined by the interplanar spacing do of the (002) plane determined from the above-mentioned X-ray wide-angle diffraction
02 is preferably 3.42A or more, more preferably 3.
．． The thickness is 44 Å or more, particularly preferably 3.48 Å or more. Further, the crystallite size Lc in the c-axis direction is preferably 7QA or less, more preferably 50A or less, particularly preferably 30A or less, and the crystallite size L in the a-axis direction
a is preferably 70A.

More preferably, it is 50 Å or less, particularly preferably 30 A or less. Furthermore, the interplanar spacing of the (110) plane (itto
The distance j111aO (=2d110) twice is preferably 2.45 Å or less, more preferably 2.37 A or more2.
It is 43A or less.

Furthermore, the carbonaceous material used for the positive electrode has one or more signals with a peak-to-peak linewidth (ΔHpp) of 7 Gauss or more determined from the -order differential absorption curve of the electron spin resonance spectrum (measured at 23°C). Either, or have no signal with a peak-to-peak linewidth (ΔHpp) less than 7 Gauss. More preferably, the peak-to-peak linewidth (ΔHpp) obtained from the -order differential absorption curve of the electron spin resonance spectrum (measured at 23°C) is equal to or more than lθ Gauss, or the peak-to-peak Either the line m(ΔHpp) of has no signal of 10 Gauss.

Furthermore, like the carbonaceous material for the negative electrode described above, the carbonaceous material constituting the positive electrode is obtained by carbonizing, that is, firing, each compound. The carbonization temperature at this time is, for example, 300
It is preferable to set the temperature to 2000°C. When a positive electrode made of such a carbonaceous material is used in combination with a negative electrode made of the above-mentioned negative electrode material, good battery performance can be achieved without the need for preliminary operations such as discharging or charging the positive electrode or negative electrode. It is possible to obtain a secondary battery having the following characteristics.

In addition, in the present invention, in addition to the metal chalcogen compound and carbonaceous material described above, a conductive polyester which dopes and dedopes electrolyte anions during charge and discharge reactions may be used as the positive electrode material. You can also do it. Examples of such conductive polymers include polyacetylene, poly(p-phenylene), polypyrrole, polythenylene, polyaniline, poly(p-phenylenesulfyF), poly
Examples include molecular compounds having a linear conjugated double bond such as (p-phenylene oxide).

Furthermore, in the non-aqueous solvent secondary battery of the present invention, as the electrolyte solution, an electrolyte salt dissolved in a non-aqueous solvent is used. As a non-aqueous solvent, propylene carbonate,
Ethylene carbonate, dimethoxyethane, γ-butyl lactone, tetrahydrofuran, 2-methyltetrahydrofuran, sulfolane, 1,3-dioxolane, etc. can be used alone or in combination of two or more. On the other hand, as electrolyte salts, C-bunchei and pFi are used.

Anions such as BFi, cF3so;, , AsFi, and L, +.

Those obtained by appropriately combining with alkali metal cations such as Na'' and K+ can be used. Examples of the cations include the above-mentioned alkali metal cations, N(CH3);, N(C2H5);

Cationic species of quaternary amines such as N(n-c3H7) may also be used.

In the non-aqueous solvent secondary battery of the present invention, which is composed of a negative electrode, a positive electrode, and an electrolyte made of each of the materials described above, electrochemical damage occurs due to doping and dedoping of alkali metal ions during charging and discharging. It was confirmed that oxidation/reduction reactions occurred, self-discharge was extremely low, and it had good cycle characteristics. In addition, the potential of the negative electrode reaction of such a secondary battery is 0 to 0 with respect to a battery using lithium metal as the negative electrode.
．． It is in the range of 8■, and a high voltage secondary battery can be obtained.

In addition, in the present invention, each measurement of elemental analysis, X-ray wide-angle diffraction, and electron spin resonance spectrum was performed by the following method.

"Elemental Analysis" Samples were dried under reduced pressure at 120° C. for about 15 hours, then dried at 100° C. for 1 hour on a hot plate in a dry box. Then, the CO generated by combustion was sampled in an aluminum cup in an argon atmosphere.
2 The carbon content from the weight of the gas, and the generated H2O
Determine the hydrogen content from the weight of. In the Examples of the present invention described later, measurements were made using a PerkinElmer 240C elemental analyzer.

"X-ray wide-angle diffraction" (1) Interplanar spacing (dQ02) of (002) plane and (
110) Interplanar spacing (dllQ) If the carbonaceous material is in the form of a powder, use it as it is, or if it is in the form of minute pieces, pulverize it in an agate mortar and add about 15% by weight of high-purity silicon powder for X-ray standards to the sample. The mixture is added as an internal standard substance, mixed, packed in a sample cell, and wide-angle X-ray diffraction curves are measured by a single-reflection diffractometer method using CuKα rays made monochromatic with a graphite monochromator as a radiation source. To correct the curve, the following simple method is used without making corrections regarding so-called Lorentz, polarization factors, absorption factors, atomic scattering factors, etc. That is, the baselines of curves corresponding to (220) and (110) diffraction are drawn, and the real intensities from the baseline are plotted again to obtain correction curves for the (002) and (110) planes. Find the midpoint of the line segment where a line parallel to the angular axis drawn at two-thirds of the peak height of this curve intersects with the diffraction curve, correct the angle at the midpoint using an internal standard, and calculate this. do02 and dlI by the following Bragg equation from the wavelength input of the CuKα ray.
Find O.

Input: 1.5418 people θ, θ': doo2. Diffraction angle corresponding to dotoo (2) Crystallite size in C-axis and a-axis directions: Lc
; La In the corrected diffraction curve obtained in the previous section, the size of the crystallite in the C-axis and a-axis directions is determined from the following equation using the so-called half value β at a position half the peak height.

There are various discussions about the shape factor K, but K=0.08
, θ, and θ° have the same meanings as in the previous section.

“Linewidth of electron spin resonance: ΔHppJ The first-order differential absorption vector of electron spin resonance is JEOL
Measure in the X band using a JES-FE IX ESR7 spectrometer. Powdered samples are left as they are, and fine flake samples are pulverized in an agate mortar, with an outer diameter of 2m1+
into a capillary tube with an outer diameter of 5IIIl.
Put it in the SR tube. The modulation of the high-frequency magnetic field is 6.3 Gauss, and all of the above steps are performed at 23° C. in an air atmosphere. The line width (ΔHpp) between the peaks of the −th order differential absorption spectrum is
Determine using Mn2+/MgO standard sample.

[Example] Examples 1 to 11 and Comparative Examples 1 to 8 1) Preparation of carbonaceous material 108 g of orthocresol, 32 g of paraformaldehyde
g and 240 g of ethyl cellosolve were charged into a reactor together with 10 g of sulfuric acid, and reacted at 115° C. for 4 hours with stirring. After the reaction was completed, 17 g of NaHCO3 and 30 g of water were added to neutralize. Then, the reaction mixture was poured into two volumes of water while stirring at high speed, and the precipitated product was filtered and dried to obtain 115 g of a linear high molecular weight novolak resin. The number average molecular weight of this product was determined by vapor pressure method (in methyl ethyl ketone,
40° C.), it was 2600.

2.25g of this novolak resin and 0.25g of hexamine
After dissolving in ethanol, the ethanol is evaporated and
It was removed to obtain a mixture of novolak resin and hexamine. This mixture was then placed in a glass container under nitrogen gas and heat treated at 250'C for 2 hours in nitrogen gas.

The heat-treated mixture thus obtained swelled in ethanol without dissolving. This swollen heat-treated mixture was heated to a temperature of 1
90℃, pressure 200Kg/crn'te width 2cm,
It was press-molded into a rectangular shape with a length of 5 cm and a thickness of 1 mm.

Next, this press molded product is set in an electric heating furnace,
210 at a heating rate of 20"07 minutes in a nitrogen stream
Carbonization was carried out by increasing the temperature to 0° C. and then maintaining this temperature, ie, 2100° C., for 1 hour in a nitrogen stream. As a result, the black strip-shaped carbonaceous material a
80 mg was obtained.

Furthermore, in the above process, the carbonization temperature was set to 1600°C.
, 1400°C, 1000°C and 800°C, but in exactly the same manner as above, respectively.
, c, d and e were obtained in an amount of 80 mg each.

The carbonization temperature [”C
], the hydrogen/carbon atomic ratio determined from elemental analysis, the interplanar spacing doo2 [in] of the (002) plane and the interplanar spacing dllo [person] of the (110) plane determined by X-ray wide-angle diffraction.

The crystallite size in the C-axis direction Lc [in], the crystallite size in the a-axis direction La [A], and the peak-to-peak line width ΔHpp [Gauss] of the electron spin resonance spectrum are summarized in Table 1. and showed. In addition, the above-mentioned items regarding graphite are also shown in the table.

As is clear from the table, among the above carbonaceous materials a to e, a and b are negative electrode materials, d and e are positive electrode materials, and C is a material that can be used for both negative and positive electrodes. be.

2) Secondary battery characteristic evaluation test A non-aqueous solvent secondary battery as shown in FIG. 1 was manufactured using each of the carbonaceous materials obtained above. That is, in the figure, 1 is a negative electrode, and each of the above carbonaceous material powders 5
0 mg was press-molded into a pellet with a diameter of 20 mm. Further, 2 is a negative electrode current collector made of nickel. The negative electrode terminal 4 is electrically connected to the negative electrode current collector 2 by a spring 3. 5 is a positive electrode,
One obtained by press-molding 50 mg of each of the above carbonaceous material powders into a pellet with a diameter of 20e+o, and after mixing 450 mg of titanium disulfide (T iS2) with 25 mg of polytetrafluoroethylene and 25 mg of acetylene black, a pellet with a diameter of 200!11 was obtained. Lumono, mata obtained by press molding into pellets is vanadium pentoxide (V2O3)4
50ag was kneaded with 25mg of polytetrafluoroethylene and 25+++g of acetylene black, and then press-molded into pellets with a diameter of 20mm.

The positive electrode 5 was pre-discharged at 2 mA for 1 hour in a propylene carbonate solution containing 1.5 mol/liter of Li (:04).The positive electrode 5 was a titanium positive electrode that also served as a positive electrode terminal. It is crimped to the current collector 6.

A separator 7 made of a nonwoven fabric of polypropylene acid is interposed between the negative electrode 1 and the positive electrode 5, and these are all pressed against each other by a spring 3. 8 and 9 are containers made of Teflon, and the contents are sealed with an O-ring 10. Furthermore, 1.5 mol/l of Li (4
2fflfL of propylene carbonate solution containing 104
is filled.

Here, the carbonaceous materials a, b, c, d shown in Table 1,
Batteries using e and graphite, TiS2, and V2O5 for the positive electrode 5 and negative electrode 1 were prepared in combinations of the two, A, B, C, D, E, F, G, H, and I, respectively.

J, L, M, N, O, P, Q, R, and S were subjected to the following characteristic evaluation tests.

(a) Charge/discharge cycle characteristic evaluation test (i+ Charge/discharge tests for each of the above batteries A-5 were conducted up to 100 cycles at 25°C in an argon atmosphere. The charging current and discharging current were all 500 gA, and immediately after charging was completed, Discharging was started.The charging voltage and discharge end voltage were each set as follows.

Batteries A-E and L, M: Charging voltage = 3.5V Discharge end voltage = 2. OV Batteries F-H and N-P: Charging voltage = 2. IV discharge end voltage = t, OV Battery I- and Q-5: Charging voltage = 3. OV discharge end voltage = 2. OV Figure 2 shows batteries A, D and L at the 5th cycle.
The charge-discharge curves are shown as curves A□ and Dl.

Ll represents the charging curves of batteries A, D, and L, respectively, and the curve m
Az, D2, and L2 each show the same discharge curve. In addition, FIG. 3 shows the battery F at the 5th cycle.
, shows the charge-discharge curves of H and O, and the song! ! F+, H
+ and 01 represent the charging curves of batteries F, H, and 0, respectively, and curves F2, H2, and 0□ represent the discharge curves of batteries I, H, and Q at the 5th cycle. Indicates charge/discharge curve, curve work □
, □ and Qz show the charging curves of batteries I, 2 and Q, respectively, and curves 12, 2 and Qz also show the discharge curves, respectively.

Table 2 also shows the charge capacity, discharge capacity, charge and discharge efficiency of each battery at the 5th cycle and 100th cycle, and the 5th cycle.
Discharge capacity ratio of cycle 1 to 100 cycle (%
)showed that.

(11) A charge/discharge test was conducted in exactly the same manner as in (1) above, except that the number of charge/discharge cycles was 50. Table 3 shows the charge capacity, discharge capacity, charge and discharge efficiency of each battery at the 10th cycle and the 50th cycle, and the discharge capacity ratio (%) of the 50th cycle to the 10th cycle.

(b) Self-discharge and storage stability evaluation test fi)
Normal charging and discharging was performed until the 9th cycle in the same manner as in (a) above, and a self-discharge test was conducted at the IO cycle. In other words, in the 10th cycle, the temperature is 25°C after charging is completed.
After being stored for 30 days in a cell, it was discharged.

Table 4 shows when the battery is immediately discharged at the 9th cycle and when the battery is discharged immediately at the 9th cycle.
The charging capacity, discharge capacity, charge/discharge efficiency when the battery was discharged after storage for 30 days at the 10th cycle, and the ratio (%) of the discharge capacity of the 10th cycle to that of the 9th cycle are shown.

(11) Normal charging and discharging was performed until the fourth cycle in the same manner as in (1) above, and a self-discharge test was conducted at the fifth cycle. That is, in the fifth cycle, after charging was completed, the battery was stored at 25° C. for 30 days, and then discharged.

Table 5 shows when discharging immediately at the 4th cycle and when discharging immediately at the 4th cycle, and when the
Charging capacity, discharging capacity, charging/discharging efficiency when discharging after 30 days of storage in the 5th cycle, and 4 in the 5th cycle.
The discharge capacity ratio (%) with respect to the cycle is shown.

[Effects of the Invention] As is clear from the above description, the non-aqueous solvent secondary battery of the present invention uses a carbonaceous material having a specific structure for the negative electrode, thereby exceeding conventional graphite as the negative electrode material. In addition, it has much better charge-discharge cycle characteristics than those using carbonaceous materials that deviate from the requirements of the present invention, and has less self-discharge and excellent storage stability. The industrial value is extremely large.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of the non-aqueous solvent secondary battery of the present invention, and FIGS. 2 to 4 are diagrams showing charge-discharge curves of the battery. 1... Negative electrode, 2... Current collector for negative electrode. 5... Positive electrode, 6... Positive electrode terminal. 7... Separator, 8.9... Volume'lA. Figure 2: Menshiki Tunbo (mAh) Figure 4: Mitsukyo's house (mAh) Figure 3: 8 views of Kokyo's house (mAh) Procedural amendment June 18, 1985 Commissioner of the Japan Patent Office Yu Ka Michibu-dono 1,! Display of I¥ 1986 Patent Application No. 820002, Name of the invention Non-aqueous solvent secondary battery 3, Relationship to the case of the person making the amendment Name of patent applicant Mitsubishi Yuka Co., Ltd. Name Toshiba Battery Co., Ltd. 4, Agent 5, Date of amendment order Motu 6, Subject of amendment Detailed explanation of the invention in the specification 7, Contents of amendment

Claims (1)

[Claims] 1. A non-aqueous solvent secondary battery comprising a rechargeable positive electrode, an electrolytic solution prepared by dissolving an electrolyte in a non-aqueous solvent, and a rechargeable negative electrode, wherein the negative electrode comprises: is obtained by carbonizing at least one compound selected from the group consisting of organic polymer compounds, fused polycyclic hydrocarbon compounds, and polycyclic heterocyclic compounds, and the atomic ratio of hydrogen/carbon is is less than 0.15, the interplanar spacing of the (002) plane determined by X-ray wide-angle diffraction is 3.37 Å or more, and the crystallite size in the c-axis direction is 15
A nonaqueous solvent secondary battery comprising a carbonaceous material having a pseudographite structure of 0 Å or less. 2. The non-aqueous solvent secondary battery according to claim 1, wherein the positive electrode is composed of a metal chalcogen compound. 3. The positive electrode is obtained by carbonizing at least one compound selected from the group consisting of organic polymer compounds, fused polycyclic hydrocarbon compounds, and polycyclic heterocyclic compounds, and the hydrogen/carbon atom ratio is The non-aqueous solvent secondary battery according to claim 1, wherein the non-aqueous solvent secondary battery is made of a carbonaceous material having a carbonaceous material of 0.10 or more and 0.70 or less.