Nonaqueous secondary battery

A nonaqueous secondary battery comprises an anode active material comprising a carbonaceous material, an electrolyte and a cathode active material comprising a lithium-containing transition metal chalcogenide. The carbonaceous material is obtained by burning a polyacrylonitrile fiber and has length of a crystallite in the c-axis direction of 75 to 250 .ANG. and an interval of 002 faces of 3.41 to 3.44 .ANG., the length and the interval being determined from an X-ray diffraction spectrum thereof using a Cu-K.alpha. ray.

FIELD OF THE INVENTION 
This invention relates to a nonaqueous secondary battery containing no 
lithium metal which has high charging-discharging capacity and excellent 
characteristics in charge-discharge cycle. 
BACKGROUND OF THE INVENTION 
A nonaqueous secondary battery basically comprises an anode active 
material, a electrolyte and a cathode active material comprising a 
lithium-containing transition metal chalcogenide and the like. In the 
secondary battery using lithium metal as the anode active material, highly 
active tree-like lithium metal (dendrite) or mossy lithium metal (moss) is 
formed on the anode during repetition of charging and discharging. When 
the dendrite or the moss peels off to become in contact with the cathode 
active material of the battery or when it grows to touch the cathode 
active material directly, an inner short circuit is produced within the 
battery. Therefore, such battery, which has insufficient characteristics 
in charge-discharge cycle, is also in great danger of ignition. In order 
to solve this problem, proposed are some batteries using lithium alloys 
such as Al, Al-Mn (U.S. Pat. No. 4,820,599), Al-Mg (Japanese Patent 
Provisional Publication No. 57(1982)-98977), Al-Sn (Japanese Patent 
Provisional Publication No. 63(1988)-6742), Al-In and Al-Cd (Japanese 
Patent Provisional Publication No. 1(1989)-144573). Use of these alloys, 
however, can not essentially prevent the battery from the production of 
inner short circuit, because lithium metal is still used for the anode 
active material. 
Recently, as the battery using no lithium metal, proposed are some 
batteries using carbonaceous materials in which lithium metal or lithium 
ion can be intercalated and then deintercalated. Such carbonaceous 
materials are roughly classified into low-graphitized carbon and 
high-graphitized carbon; the former comprises both an amorphous portion 
and a crystalline portion, and the latter comprises little amorphous 
portion and is prepared by heating various low-graphitized carbons at a 
temperature of higher than 2,400.degree. C. These two carbonaceous 
materials are clearly different from in terms of properties, so that they 
are generally distinguished each other and employed for different purposes 
("Carbonaceous Material Engineering" by Michio Inagaki, published by 
NIKKAN KOGYO SHINBUN-SHA (1985)). These carbonaceous materials can be 
generally obtained as natural products or by burning various organic 
compounds. 
High-graphitized carbon has essentially high charging-discharging capacity 
(Physical Review B, vol.42(1990), pp. 6424). However, when the 
high-graphitized carbon is used as an anode active material, the cathode 
material must be added in an excessive amount at the beginning of 
charge-discharge cycle because irreversible capacity loss, socalled 
"exfoliation", occurs (Journal of Electrochemical Society, 
vol.1,137(1990), pp.2009). Consequently, the charging-discharging capacity 
of such battery is relatively low. In order to solve this problem, a 
battery using the combination of the cathode containing no lithium metal 
and the anode comprising a compound sandwiching lithium metal between 
graphite layers (lithium metal-graphite-sandwich compound) which is 
previously prepared is proposed in Japanese Patent Publication No. 
62(1987)-23433 and U.S. Pat. No. 4,423,125. However, the lithium 
metal-graphite-sandwich compound is in danger of ignition and decomposes 
in the presence of even a slight amount of water, and therefore it is 
difficult to incorporate such material in a battery. Further, a battery 
using the combination of the graphite anode and the cathode containing 
lithium metal is also proposed ("31st Conference of Battery (1990)" 
pp.97). Even in such battery, however, an excess amount of the cathode 
material must be added so as to compensate the capacity loss of the 
exfoliation. Consequently, such battery also hardly brings about increase 
of the capacity. Further, Japanese Patent Provisional Publication No. 
3(1992)-129664 discloses a battery using the combination of the fine 
fibrous Graphite and the cathode containing lithium metal. However, this 
battery also has small charging-discharging capacity because the density 
of the graphite material is very small. 
On the other hand, as for carbonaceous material showing low exfoliation, 
there are proposed many batteries in which low-graphitized carbon is used 
for the anode (Japanese Patent Provisional Publication Nos. 
58(1983)-209864, 61(1986)-214417, 62(1987)-88269, 62(1987)-90863, 
62(1987)-122066, 62(1987)-216170, 63(1988)-13282, 63(1988)-24555, 
63(1988)-121247, 63(1988)-121257, 63(1988)-155568, 63(1988)-276873, 
63(1988)-314821, 1(1989)-204361, 1(1989)-221859, 2(1990)-230660, 
1(1989)-274360, 2(1990)-284354, 3(1991)-122974, and WO090/13,924). Even in 
the above batteries using low-graphitized carbon for the anode, however, 
the irreversible capacity loss at an early stage of charging which is 
caused by the exfoliation is still large. Thus, a lithium secondary 
battery having satisfactory charging-discharging capacity loss has not 
been produced up to now. In addition, low-graphitized carbonaceous 
material is known to show charging-discharging capacity lower than that of 
high-graphitized carbonaceous material (Physical Review B, vol.42 (1990), 
pp.6424). 
As is described above, any of known carbonaceous materials does not have 
satisfying characteristics needed for an anode active material of a 
lithium secondary battery, such as reduced charging-discharging capacity 
loss, increased charging-discharging capacity and assured safety. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a nonaqueous secondary 
battery having an anode active material of a carbonaceous material which 
has high safety, high charging-discharging capacity, reduced 
charging-discharging capacity loss and a long life in charge-discharge 
cycle. 
It is another object of the present invention to provide a small-sized 
lithium secondary battery having high energy density. 
The present inventors have studied in order to obtain an anode active 
material having reduced charging-discharging capacity loss and increased 
charging-discharging capacity. As a result, they have found that a 
carbonaceous material giving an X-ray diffraction spectrum in the 
following range, satisfies the above excellent characteristics. 
The invention resides in a nonaqueous secondary battery which comprises an 
anode active material comprising a carbonaceous material, an electrolyte 
and a cathode active material comprising a lithium-containing transition 
metal chalcogenide; 
wherein said carbonaceous material has length of a crystallite in c-axis 
direction of 75 to 250 .ANG. and an interval of 002 faces of 3.41 to 3.44 
.ANG., said length and said interval being determined from an X-ray 
diffraction spectrum thereof using Cu-K.alpha.ray. 
Preferred embodiments of the above nonaqueous secondary battery are as 
follows: 
(1) The nonaqueous secondary battery wherein the carbonaceous material has 
an essentially single diffraction peak of which half width is in the range 
of 0.5 to 1.2 degree, the peak being shown in an X-ray diffraction 
spectrum thereof using Cu-K.alpha. ray. 
(2) The nonaqueous secondary battery wherein the carbonaceous material is a 
burned polyacrylonitrile or a burned copolymer of acrylonitrile and other 
monomers polymerizable with the acrylonitrile. 
(3) The nonaqueous secondary battery wherein the carbonaceous material is a 
burned polyacrylonitrile fiber. 
(4) The nonaqueous secondary battery wherein the carbonaceous material is a 
burned polyacrylonitrile fiber of 0.4 to 40 denier. 
(5) The nonaqueous secondary battery wherein the carbonaceous material has 
the magnetic resistance (.DELTA..rho./.rho.).sub.cr of -0.01 to -0.99 (%). 
(6) The nonaqueous secondary battery wherein the anode active material 
contains fine carbon particles and/or fine carbon fibers together with 
said carbonaceous material. 
(7) The nonaqueous secondary battery as defined in claim 1, wherein the 
lithium-containing transition metal chalcogenide is LiCoO.sub.2. 
(8) The secondary battery wherein the lithium-containing transition metal 
chalcogenide is Li.sub.a Co.sub.b V.sub.c O.sub.d (in which a=0 to 1.1, 
b=0.8 to 0.98, c=1-b and d=2.05 to 2.6). 
The length (Lc) of a crystallite in c-axis direction is determined from an 
X-ray diffraction spectrum using Cu-K.alpha. ray in the following manner: 
EQU Lc(.ANG.)=K.multidot..lambda./.beta..multidot.cos.theta. 
in which K indicates 0.9, .lambda. indicates wave length of Cu-K.alpha. 
ray, .beta. indicates half width of a peek and .theta. indicates degree of 
diffraction. 
The interval of 002 faces (d.sub.002) is determined from an X-ray 
diffraction spectrum using Cu-K.alpha. ray in the following manner: 
EQU d.sub.002 (.ANG.)=.lambda./2.multidot.sin.theta. 
in which .lambda. indicates wavelength of Cu-K.alpha. ray and .theta. 
indicates degree of diffraction. 
The interval of 002 faces (d.sub.002) is also determined from a maximum of 
diffraction peak. 
The invention also resides in a nonaqueous secondary battery which 
comprises an anode active material comprising a carbonaceous material, an 
electrolyte and a cathode active material comprising a lithium-containing 
transition metal chalcogenide; 
wherein said carbonaceous material is obtained by burning polyacrylonitrile 
fiber of 0.4 to 40 denier at 2,400.degree. to 3,500.degree. C. 
Preferred embodiments of the above nonaqueous secondary battery are as 
follows: 
(1) The nonaqueous secondary battery wherein the carbonaceous material is 
obtained by burning said polyacrylonitrile fiber at 2,400.degree. to 
3,500.degree. C., the carbonaceous material being subjected to a first 
burning step of heating said fiber at 150.degree. to 300.degree. C. and 
thereafter cooling, and a second burning step of burning said fiber at 
400.degree. to 2000.degree. C. and thereafter cooling, before said burning 
at 2,400.degree. to 3,500.degree. C. 
(2) The nonaqueous secondary battery wherein said carbonaceous material is 
obtained by burning said polyacrylonitrile fiber at 2,400.degree. to 
3,500.degree. C., said carbonaceous material being subjected to a first 
burning step of heating said fiber at 150.degree. to 300.degree. C. and 
thereafter cooling, a second burning step of heating said fiber at 
400.degree. to 800.degree. C. and thereafter cooling, and a third burning 
step of heating said fiber at 900.degree. to 2000.degree. C. and 
thereafter cooling, before said burning at 2,400.degree. to 3,500.degree. 
C. 
(3) The nonaqueous secondary battery, wherein said burning of said 
polyacrylonitrile fiber is conducted in the condition of no orientation. 
The nonaqueous secondary battery of the invention having an anode active 
material of a carbonaceous material which has length of a crystallite in 
c-axis direction of 75 to 250 .ANG. and an interval of 002 faces of 3.41 
to 3.44 .ANG., is extremely improved in charging-discharging capacity loss 
and charging-discharging capacity compared with a conventional nonaqueous 
secondary battery. 
The carbonaceous material is advantageously obtained by burning 
polyacrylonitrile fiber of 0.4 to 40 denier at 2,400.degree. to 
3,500.degree. C. In the burning, the polyacrylonitrile fiber receives 
restrain of arrangement, which is derived from CN bond of 
polyacrylonitrile, and therefore that it is supposed that the carbonaceous 
material of the invention is easily obtained by burning the specific 
polyacrylonitrile fiber in the specific conditions.

DETAILED DESCRIPTION OF THE INVENTION 
As materials (precursors) of the carbonaceous material used in the 
nonaqueous secondary battery of the invention, there can be mentioned 
fibers and resins of acrylonitrile homopolymer and copolymers of 
acrylonitrile and other monomer(s) polymerizable with the acrylonitrile. 
Examples of the acrylonitrile copolymers include copolymers of 
acrylonitrile and at least one of monomers such as vinyl acetate, vinyl 
chloroacetate, acrylic acid, acrylic acid ester, methacrylic acid ester, 
itaconic acid ester, vinylpyridine, vinylquinoline, vinylimide, 
vinyloxazole, vinylimidazole, acrylamide, vinyl ether, methallyl alcohol, 
vinyl chloride, vinylidene chloride, styrene, vinyltoluene, allylsulfonate 
(Li, Na and K), methallylsulfonate (Li, Na and K), and 
vinylbenzenesulfonates (Li, Na and K). 
The amount of the co-polymerized monomer unit is in a range of 0.01 to 50 
wt.%, preferably 0.1 to 30 wt.% based on the total amount of the 
copolymer. 
Fiber of the acrylonitrile homopolymer or copolymer (i.e., 
polyacrylonitrile fiber) is preferably used as material of the 
carbonaceous material of the invention. The molecular weight of the fiber 
preferably is in a range of 50,000 to 100,000. The characteristics of the 
carbonaceous material is considered to depend on the thickness of 
polyacrylonitrile fiber. The thickness of the fiber generally is in a 
range of 0.4 to 40 denier, preferably 5 to 25 denier, and more preferably 
10 to 25 denier. Further, fibers may be generally classified into two 
types, i.e., the fibers having high gloss ("bright") and those having low 
gloss ("dull"). Preferred are bright fibers. Further profile cross section 
fibers and composite cross section fibers may be also employed. 
The carbonaceous material is preferably prepared by burning the 
above-mentioned fiber at 2,400.degree. to 3,500.degree. C. (preferably in 
the condition of not orienting the fibers). Before the polyacrylonitrile 
fiber is heated at 2,400.degree. to 3,500.degree. C., the fiber is 
preferably subjected to a burning process of 2 or 3 steps. The burning 
process of 2 or 3 steps preferably includes a process comprising a 
combination of a first burning step of heating at 150.degree. to 
300.degree. C. and a second burning step of heating at 400.degree. to 
2000.degree. C. (three-steps burning process), or a combination of a first 
burning step of heating at 150.degree. to 300.degree. C., a second burning 
step of heating at 400.degree. to 800.degree. C. and a third burning step 
of heating at 900.degree. to 2,000.degree. C. (four-steps burning 
process). 
The four-steps burning process is, for example, performed without 
orientation of the fiber in the manner described in Table 1 (four-steps). 
"Burning without orientation" in the present specification means that the 
fibers are not stretched in the direction of the fiber axis during burning 
process. 
TABLE 1 
______________________________________ 
Temp. (.degree.C.) 
Period (hour) 
Atmosphere 
______________________________________ 
Step 1 
150-300 0.5-3 air 
Step 2 
400-800 0.5-3 inert gas or vacuum 
Step 3 
900-2000 0.5-3 inert gas or vacuum 
Step 4 
2400-3500 0.5-5 argon gas 
______________________________________ 
In the process for the preparation of the polyacrylonitrile carbonaceous 
material by carbonizing polyacrylonitrile fiber, the fiber is generally 
stretched in the direction of the fiber axis during burning process in 
order to give enough strength to the resultant carbonized material. Such 
process is named the burning with orientation. On the other hand, 
polyacrylonitrile fiber is preferably burned without orientation in the 
invention. The above four-steps burning process comprises: burning in air 
at 150.degree. to 300.degree. C. and thereafter cooling; burning in an 
inert Gas such as argon, helium and nitrogen or in vacuum at 800.degree. 
to 2,000.degree. C. and thereafter cooling; and finally burning at 
2,400.degree. to 3,500.degree. C. As long as the final burning is carried 
out at higher than 2,400.degree. C., the charging-discharging capacity 
loss can be considerably reduced. However, final burning is appropriately 
conducted at 2,400.degree. to 3,500.degree. C. to obtain the anode active 
material of the invention, preferably at 2,500.degree. to 3,500.degree. C. 
and more preferably at 3,000.degree. to 3,500.degree. C. Carbonizing 
stage is Generally carried out in inert Gases such as argon, helium and 
nitrogen or in vacuum. If the carbonizing stage is carried out in vacuum, 
the degree of vacuum is not more than 1 mmHG, and preferably not more than 
0.1 mmHG. Preferably, the final burning is carried out in argon 
atmosphere. In each of the steps before the final burning step, cooling is 
generally conducted after heating (burning). The cooling is preferably 
conducted by allowing the burned material to reach room temperature. 
Three step burning process shown in Table 2 is also advantageous to obtain 
the characteristics of X-ray diffraction of the carbonaceous material of 
the invention. The final burning step of the three steps burning process 
is also preferred to be carried out in the same manner as described in the 
four-steps burning step. In each of the steps before the final burning 
step, cooling is generally conducted after heating (burning). The cooling 
is preferably conducted in the same manner as above. 
TABLE 2 
______________________________________ 
Burning Conditions (3-Steps) 
Temp. (.degree.C.) 
Period (hour) 
Atmosphere 
______________________________________ 
Step 1 150-300 0.5-3 air 
Step 2 400-2000 0.5-3 inert gas or vacuum 
Step 3 2400-3500 0.5-5 argon gas 
______________________________________ 
The carbonaceous material of the invention is advantageously obtained by 
the above process. In the carbonaceous material, the length of a 
crystallite in c-axis direction, which is determined from an X-ray 
diffraction spectrum thereof using Cu-K.alpha. ray, is in the range of 75 
to 250 .ANG., preferably in the range of 80 to 200 .ANG. and more 
preferably in the range of 85 to 170 .ANG.. The interval of 002 faces, 
which is determined from the X-ray diffraction spectrum is 3.41 to 3.44 
.ANG., preferably in the range of 3.41 to 3.43 .ANG., and more preferably 
in the range of 3.41 to 3.42 .ANG.. Further, the carbonaceous material is 
preferred to have an essentially single diffraction peak of which half 
width (difference of values of 2.theta.) is in the range of 0.5 to 1.2 
degree, the peak being shown in the X-ray diffraction spectrum. The 
carbonaceous material of the invention used as the anode active material, 
has a mean grain size of 2 to 150 .mu.m, preferably 5 to 100 .mu.m, which 
is generally prepared by graining the material into particles. 
Fine carbon particles and fine carbon fibers is preferably mixed into the 
burned carbonaceous material used for the battery of the invention, and 
such mixed material preferably improves the conductivity. Preferable 
examples of such carbon include carbon blacks such as acetylene black, 
furnace black and ketchen black. The amount of the carbon is preferably 
not more than 30%, more preferably not more than 20%, and particularly 
preferably not more than 15%. 
Binders and/or reinforcing agents generally used may be added into a 
mixture for anode (depolarizing mix for anode) containing the carbonaceous 
material of the invention. 
Examples of binders include natural polysaccharide, synthesized 
polysaccharide, synthesized polyhydroxyl compounds, polymers obtained by 
polymerizing mainly acrylic acid, fluorine-containing compounds and 
synthesized rubber. Preferred examples include starch, carboxymethyl 
cellulose, diacetyl cellulose, hydroxylpropyl cellulose, polyethylene 
oxide, polyacrylic acid, polytetrafluoroethylene, polyfluorovinylidene, 
ethylene-propylene-diene copolymer and polyacrylonitrile-butadiene 
copolymer. 
As the reinforcing agent, fibers which do not react with lithium can be 
employed. Preferred examples of such fibers include synthesized polymers 
or carbon fibers such as polypropylene fiber, polyethylene fiber and 
Teflon fiber. The fibers are preferably 0.1 to 4 mm in length and 0.1 to 
50 denier in thickness, more preferably 1 to 3 mm in length and 1 to 6 
denier in thickness. 
For a battery of coin-type or button-type, the mixture for anode is molded 
and pressed to form a pellet, and the resultant pellet is used. For a 
battery of cylindrical type, an anode of sheet-type is used. Such anode of 
sheet-type is produced by applying the mixture onto a collector and then 
rolling the applied collector, or by superposing the pressed sheet of the 
mixture onto a collector and then rolling the superposed sheet. The 
obtained anode sheet is wound up to use for the battery. 
Examples of the cathode active material comprising a lithium-containing 
transition metal chalcogenide employable for the invention include lithium 
compounds of MnO.sub.2, Mn.sub.2 O.sub.4, Mn.sub.2 O.sub.3, CoO.sub.2, 
Co.sub.x Mn.sub.1-x O.sub.y, Ni.sub.x Co.sub.1-x O.sub.y, V.sub.x 
Mn.sub.1-x O.sub.y, Fe.sub.x Mn.sub.1-x O.sub.y, V.sub.2 O.sub.5, V.sub.3 
O.sub.8, V.sub.6 O.sub.13, Co.sub.x V.sub.1-x O.sub.y, MoS.sub.2, 
MoO.sub.3 and TiS.sub.2 (0&lt;x&lt;1, 0&lt;y&lt;1). Particularly preferred is 
LiCoO.sub.2 or Li.sub.a Co.sub.b V.sub.c O.sub.d (a =0 to 1.1, b=0.8 to 
0.98, c=1 - b, and d=2.05 to 2.6). The lithium-containing transition metal 
chalcogenide is generally prepared by ion-exchange or by burning a lithium 
compound with a transition metal compound. Any known method can be used 
for preparing the transition metal chalcogenide, but the burning process 
is preferably carried out at 200.degree. to 1,500.degree. C. in air or in 
inert gases such as argon and nitrogen. 
The electrolytic conductor comprises a solvent containing at least one 
aprotic organic solvent, and one or more lithium salts (comprising anion 
and lithium cation) which are soluble in the solvent. 
Examples of the aprotic organic solvent include propylene carbonate, 
ethylene carbonate, diethylcarbonate, .gamma.-butyrolactone, methyl 
formate, methyl acetate, 1,2-dimethoxyethane, tetrahydrofuran, 
2-methyltetrahydrofuran, dimethyl sulfoxide, 1,3-dioxolan, formamide, 
dimethylformamide, dioxolan, acetonitrile, nitromethane, ethylmonoglyme, 
phosphoric acid triester (Japanese Patent Provisional Publication No. 
60(1985)-23973), trimethoxymethane (Japanese Patent Provisional 
Publication No. 61(1986)-4170), dioxolan derivatives (Japanese Patent 
Provisional Publication Nos. 62(1987)-15771, 62(1987)-22372 and 
62(1988)-108473), sulfolane (Japanese Patent Provisional Publication No. 
62(1987)-31959), 3-methyl-2-oxazolidinone (Japanese Patent Provisional 
Publication No. 62(1987)-44961), propylene carbonate derivatives (Japanese 
Patent Provisional Publication Nos. 62(1987)-290069 and 62(1987)-290071), 
tetrahydrofuran derivatives (Japanese Patent Provisional Publication No. 
63(1988)-32872), ethyl ether (Japanese Patent Provisional Publication No. 
63(1988)-62166) and 1,3-propanesultone (Japanese Patent Provisional 
Publication No. 63(1988)-102173). 
Examples of the lithium salt include: salts of ClO.sub.4.sup.-, 
BF.sub.4.sup.-, PF.sub.6.sup.-, CF.sub.3 SO.sub.3.sup.-, CF.sub.3 
CO.sub.2.sup.-, AsF.sub.6.sup.-, SbF.sub.6.sup.-, (CF.sub.3 
SO.sub.2).sub.2 N.sup.-, B.sub.10 Cl.sub.10.sup.- (Japanese Patent 
Provisional Publication No. 57(1982)-74974) and 
(1,2-dimethoxyethane).sub.2 ClO.sub.4.sup.- (Japanese Patent Provisional 
Publication No. 57(1982)-74977); lower aliphatic carboxylic acids 
(Japanese Patent Provisional Publication No. 60(1985)-41773); 
AlCl.sub.4.sup.-, Cl.sup.-, Br.sup.- and I.sup.- (Japanese Patent 
Provisional Publication No. 60(1985)-247265); chloroborane (Japanese 
Patent Provisional Publication No. 61(1986)-165957); and tetraphenylborate 
(Japanese Patent Provisional Publication No. 61(1986)-214376). 
A preferred example of the electrolyte is an electrolytic solution prepared 
by dissolving LiClO.sub.4 or LiBF.sub.4 in a mixture of propylene 
carbonate and 1,2-dimethoxyethane. 
In addition to electrolytic solutions, solid electrolytes described below 
are also employable. Solid electrolytes can be classified into inorganic 
solid electrolytes and organic solid electrolytes. 
As the inorganic solid electrolytes, lithium nitride, lithium halide and 
oxyacidic salts of lithium can be mentioned. Examples of the inorganic 
solid electrolytes preferably employable for the invention include 
Li.sub.3 N, LiI, Li.sub.5 NI.sub.2, Li.sub.3 N-LiI-LiOH, LiSiO.sub.4, 
LiSiO.sub.4 -LiI-LiOH (Japanese Patent Provisional Publication No. 
49(1974)-81899), xLi.sub.3 PO.sub.4 -(1-x) Li.sub.4 SiO.sub.4 (Japanese 
Patent Provisional Publication No. 59(1984)-60866), Li.sub.2 SiS.sub.3 
(Japanese Patent Provisional Publication No. 60(1985)-501731) and 
phosphorus sulfide compounds (Japanese Patent Provisional Publication No. 
62(1987)-82665). 
Examples of the organic solid electrolytes employable for the invention 
include: polyethylene oxide derivatives or polymers containing said 
derivatives (Japanese Patent Provisional Publication No. 63(1988)-135447); 
polypropylene oxide derivatives or polymers containing said derivatives; 
polymers containing ion-dissociating groups (Japanese Patent Provisional 
Publication Nos. 62(1987)-254302, 62(1987)-254303 and 63(1988)-193954); a 
mixture of polymers containing ion-dissociating groups and the 
above-mentioned aprotic electrolytic solutions (U.S. Pat. Nos. 4,792,504 
and 4,830,939, Japanese Patent Provisional Publication Nos. 
62(1987)-22375, 62(1987)-22376, 63(1988)-22375, 63(1988)-22776 and 
1(1989)-95117); phosphoric acid ester polymer (Japanese Patent Provisional 
Publication No. 61(1986)-256573); and polymer matrix material containing 
aprotic polar solvent (U.S. Pat. Nos. 4,822,70 and 4,830,939, Japanese 
Patent Provisional Publication No. 63(1988)-239779, Japanese Patent 
Application Nos. 2(1990)-30318 and 2(1990)-78531). 
In addition to the above solid electrolytes, an electrolytic solution 
containing polyacrylonitrile (Japanese Patent Provisional Publication No. 
62(1987)-278774) may be also employed. Further, inorganic and organic 
solid electrolytes may be used in combination (Japanese Patent Provisional 
Publication No. 60(1985)-1768). 
A separator provided between the anode and the cathode is an insulated film 
having both high ion permeability and desired mechanical strength. A 
generally used separator is a porous sheet or non-woven fabric made of 
olefinic polymers such as polypropylene or a sheet of glass fiber, because 
they have hydrophobic property and organic solvent resistance. Further, 
there can be employed a modified separator prepared by the method that 
acryloyl monomer having polyethylene oxide group connecting to the side 
chain is graft-polymerized by plasma on the surface of porous film of 
polypropylene or polyethylene. 
The other compounds may be added into the electrolyte in order to improve 
characteristics in charge-discharge cycle. Examples of the compounds 
include pyridine (Japanese Patent Provisional Publication No. 
49(1974)-108525), triethylphosphite (Japanese Patent Provisional 
Publication No. 47(1972)-4376), triethanolamine (Japanese Patent 
Provisional Publication No. 52(1977)-72425), cyclic ethers (Japanese 
Patent Provisional Publication No. 57(1982)-152684), ethylene diamine 
(Japanese Patent Provisional Publication No. 58(1983)-87777), n-grime 
(Japanese Patent Provisional Publication No. 58(1983)-87778), 
hexaphosphoric acid triamide (Japanese Patent Provisional Publication No. 
58(1983)-87779), nitrobenzene derivatives (Japanese Patent Provisional 
Publication No. 58(1983)-214281), sulfur (Japanese Patent Provisional 
Publication No. 59(1984)-8280), quinoneimine dye (Japanese Patent 
Provisional Publication No. 59(1984)-68184), N-substituted oxazolidinone 
and N,N'-substituted imidazolidinone (Japanese Patent Provisional 
Publication No. 59(1984)-154778), ethylene glycol dialkyl ether (Japanese 
Patent Provisional Publication No. 59(1984)-205167), quaternary ammonium 
salts (Japanese Patent Provisional Publication No. 60(1985)-30065), 
polyethylene glycol (Japanese Patent Provisional Publication No. 
60(1985)-41773), pyrrole (Japanese Patent Provisional Publication No. 
60(1985)-79677), -2methoxyethanol (Japanese Patent Provisional Publication 
No. 60(1985)-89075), AlCl.sub.3 (Japanese Patent Provisional Publication 
No. 61(1986)-88466), monomer of the conductive polymer used as the active 
material (Japanese Patent Provisional Publication No. 61(1986)-161673), 
triethylenephosphoramide (Japanese Patent Provisional Publication No. 
61(1986)-208758), trialkylphophine (Japanese Patent Provisional 
Publication No. 62(1987)-80976), morpholine (Japanese Patent Provisional 
Publication No. 62(1987)-80977), aryl compounds having carbonyl group 
(Japanese Patent Provisional Publication No. 62(1987)-86673), crown ethers 
such as 12-crown-4 (Physical Review B, vol.42(1990) pp.6424), 
hexamethylphosphoric triamide and 4-alkylmorpholine (Japanese Patent 
Provisional Publication No. 62(1987)-217575), bicyclic tertiary amine 
(Japanese Patent Provisional Publication No. 62(1987)-217578), oils 
(Japanese Patent Provisional Publication No. 62(1987)-287580 ), quaternary 
phosphonium salts (Japanese Patent Provisional Publication No. 
63(1988)-121268) and tertiary sulfonium salts (Japanese Patent Provisional 
Publication No. 63(1988)-121269). 
In order to render the electrolytic solution noncombustible, 
halogen-containing solvents such as carbon tetrachloride and ethylene 
chloride trifluoride may be added (Japanese Patent Provisional Publication 
No. 48(1972)-36632). Further, carbon dioxide may be contained in the 
electrolytic solution so as to give preservability at high temperatures 
(Japanese Patent Provisional Publication No. 59(1984)-134567). 
The cathode active material may contain an electrolytic solution or an 
electrolyte. Examples of the materials of the electrolytic solution or 
electrolyte include the above-mentioned ion conductive polymers and 
nitromethane (Japanese Patent Provisional Publication No. 48(1973)-36633, 
or electrolytic solutions (Japanese Patent Provisional Publication No. 
57(1982)-124870). 
Otherwise, the surface of the cathode active material may be modified. For 
example, the surface of the metal oxide can be treated with an agent for 
esterification (Japanese Patent Provisional Publication No. 
55(1980)-163779), a chelating agent (Japanese Patent Provisional 
Publication No. 55(1980)-163780), conductive polymers (Japanese Patent 
Provisional Publication Nos. 58(1983)-163188 and 59(1984)-14274), or 
polyethylene oxide (Japanese Patent Provisional Publication No. 
60(1985)-97561). 
Further, the surface of the anode active material may be modified. For 
example, a layer of ion conductive polymer or a layer of polyacetylene may 
be provided on the surface (Japanese Patent Provisional Publication No. 
58(1983)-111276), or the surface may be treated with LiCl (Japanese Patent 
Provisional Publication No. 58(1983)-142771) or with ethylene carbonate 
(Japanese Patent Provisional Publication No. 59(1984)-31573). 
As the carrier of the cathode active material, foil of stainless steel, 
nickel or aluminum is generally used. In addition to these metals, also 
employable are porous foamed metal, which is suitable for conductive 
polymer (Japanese Patent Provisional Publication No. 59(1984)-18578), 
titanium (Japanese Patent Provisional Publication No. 59(1984)-68169), 
expanded metal (Japanese Patent Provisional Publication No. 
61(1986)-264686) and punched metal. 
As the carrier of the anode active material, foil of stainless steel, 
nickel, titanium or aluminum is generally used. In addition to these 
metals, also employable are porous nickel (Japanese Patent Provisional 
Publication No. 58(1983)-18883), porous aluminum (Japanese Patent 
Provisional Publication No. 58(1983)-38466), sintered aluminum (Japanese 
Patent Provisional Publication No. 59(1984)-130074), moldings of aluminum 
fibers (Japanese Patent Provisional Publication No. 59(1984)-148277), 
silver-plated stainless steel (Japanese Patent Provisional Publication No. 
60(1985)-41761), burned carbonaceous material such as burned phenolic 
resin (Japanese Patent Provisional Publication No. 60(1985)-112254), Al-Cd 
alloy (Japanese Patent Provisional Publication No. 60(1985)-211779) and 
porous foaming metal (Japanese Patent Provisional Publication No. 
61(1986)-74268). 
As a collector, any electronic conductor can be employed unless it induces 
chemical reaction in the prepared battery. For example, stainless steel, 
titanium and nickel are generally used. Further, also employable are 
nickel-plated copper (Japanese Patent Provisional Publication No. 
48(1973)-36627), titanium-plated copper and copper-treated stainless steel 
which is suitable when sulfides are used as the cathode active material 
(Japanese Patent Provisional Publication No. 60(1985)-175373). 
The above-mentioned materials can be employed for a battery of any shape 
such as coin-type, button-type, sheet-type or cylindrical type. 
The following examples further illustrate the present invention, but these 
examples by no means restrict the invention. 
EXAMPLE 1 
A carbonaceous material was prepared by burning polyacrylonitrile fiber 
(Cashmilon FCW BR of Asahi Chemical Industry Co., Ltd.; 15 denier) in the 
condition of no orientation in the following manner: 
STEP 1: increasing temperature in air from room temperature to 230.degree. 
C. at the rate of 12.degree. C./minute, keeping the temperature of 
230.degree. C. for 1 hour, and then cooling to room temperature for 2 
hours; by means of a muffle furnace (FP-31 available from Yamato 
Scientific Co., Ltd.), 
STEP 2: increasing temperature in argon from room temperature to 
500.degree. C. at the rate of 15.degree. C./minute, keeping the 
temperature of 500.degree. C. for 1 hour, and then cooling to room 
temperature for 3 hours; by means of a muffle furnace (FP-31 available 
from Yamato Scientific Co., Ltd.), 
STEP 3: increasing temperature in vacuum of 10.sup.-5 to 10.sup.-6 mmHg 
from room temperature to 1,000.degree. C. at the rate of 95.degree. 
C./minute, keeping the temperature of 1,000.degree. C. for 1 hour, and 
then cooling to room temperature for 1 hour; by means of a high 
temperature vacuum furnace (TV-1300R available from Tokyo Shinku Co., 
Ltd.), and 
STEP 4: increasing temperature from room temperature to 3,000.degree. C. at 
the rate of 6.degree. C./minute, keeping the temperature of 3,000.degree. 
C. for 1 hour, and then cooling to room temperature for 36 hours. 
X-ray diffraction spectrum of Cu-K.alpha. ray of the obtained carbonaceous 
material is shown in FIG. 2. It was determined from the X-ray diffraction 
spectrum that the interval of 002 faces (i.e., maximum of the diffraction 
peak) was 3.42 .ANG., the length of a crystallite in c-axis direction was 
98.2 .ANG., and the half width (2.theta.) of the diffraction peak was 
0.77.degree.. The diffraction peak was essentially single in the range of 
0.5 to 1.2.degree. (half width (2.theta.)). Further, the magnetic 
resistance (.DELTA..rho./.rho.).sub.cr of the obtained carbonaceous 
material was confirmed to be negative. 
The prepared carbonaceous material was grained in an automatic mortar (Type 
ANM1000 available from Nitto Kagaku Co., Ltd.) into particles of a mean 
size of 18 .mu.m (measured in the laser diffraction type-grain size 
analyzer LA-500 available from Horiba, Ltd.). The obtained carbonaceous 
material powder (80 wt.%), acetylene black (Denkablack available from 
Denki Kagaku Kogyo K.K.; 10 wt.%), polytetrafluoroethylene (Wako Wako Pure 
Chemical Industries, Ltd.; 5 wt.%) and ethylene-propylene-diene copolymer 
EPDM (ESPRENE available from Sumitomo Chemical Co., Ltd.; 5 wt.%) were 
dispersed in toluene, sufficiently stirred to mix and then dried to 
prepare a mixture for anode (depolarizing mix for anode). The obtained 
mixture was molded and pressed to form a pellet (Diameter: 13 mm). The 
prepared pellet was used as an anode material. 
Independently, Li.sub.1.0 Co.sub.0.95 V.sub.0.05 O.sub.2.5 (85 wt.%), 
acetylene black (Denkablack available from Denki Kagaku Kogyo K.K.; 10 
wt.%) for conductor and polytetrafluoroethylene (Wako Pure Chemical 
Industries, Ltd.; 5 wt.%) for binder were mixed to prepare a mixture for 
cathode (depolarizing mix for cathode). The obtained mixture was molded 
and pressed to form a pellet (Diameter: 13 mm). The prepared pellet was 
used as a cathode material. The volume ratio of the cathode to the anode 
was adjusted to 15 so that the characteristics of the constituted battery 
might mainly depend on the anode. 
As the electrolytic conductor, 1 mol/1 solution of LiBF.sub.4 (dissolved in 
a solvent which was prepared by mixing equal volumes of propylene 
carbonate and 1,2-dimethoxyethane) was used. A porous sheet of 
polypropylene and nonwoven fabric of polypropylene were superposed and 
used as the separator. 
In the above-described manner, a secondary battery of coin-type shown in 
FIG. 1 was produced (Battery 1). 
In FIG. 1, the anode pellet 2 is sealed between the anode seal 1 and the 
separator 3, the cathode seal 1 is sealed between the cathode case 6 
having the collector 5 and the separator 3, and the gasket 7 is provided 
between the outer periphery of the anode seal 1 and that of the gasket 7. 
The charging-discharging test was carried out by iteratively charging the 
battery at 150 mAH/g and discharging from the battery to 3.2 V, current 
density being 1 mA/cm.sup.2. In the test, the charging-discharging 
capacity loss was measured after the 10th cycle was complete, and the 
charging-discharging capacity was measured at the 25th cycle to evaluate 
the performance of the battery. 
EXAMPLE 2 
The procedures of Example 1 were repeated except for not adding acetylene 
black to the anode material to prepare a secondary battery (Battery 2). 
With respect to the obtained battery, the same test as described in 
Example 1 was carried out. 
EXAMPLE 3 
The procedures of Example 1 were repeated except for using LiCoO.sub.2 in 
stead of Li.sub.1.0 Co.sub.0.95 V.sub.0.05 O.sub.2.5 as the cathode 
material to prepare a secondary battery (Battery 3). With respect to the 
obtained battery, the same test as described in Example 1 was carried out. 
EXAMPLE 4 
A carbonaceous material was prepared in the same manner as described in 
Example 1 except for using another polyacrylonitrile fiber (Cashmilon FK 
BR available from Asahi Chemical Industry Co., Ltd.; 5 denier) in stead of 
the polyacrylonitrile fiber of Example-1 (Cashmilon FCW BR available from 
Asahi Chemical Industry Co., Ltd.; 15 denier). It was determined from the 
X-ray diffraction spectrum of the obtained carbonaceous material that an 
interval of 002 faces (i.e., maximum of the diffraction peak) was 3.42 
.ANG., length of a crystallite in c-axis direction was 91.0 .ANG., and the 
half width (2.theta.) of the diffraction peak was 0.89.degree.. Further, 
the magnetic resistance (.DELTA..rho./.rho.).sub.cr of the obtained 
carbonaceous material was confirmed to be negative. 
The prepared carbonaceous material was grained into particles of mean size 
25 .mu.m in the same manner as described in Example 1. Using the 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery 4). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
EXAMPLE 5 
A carbonaceous material was prepared in the same manner as described in 
Example 1 except for using another polyacrylonitrile fiber (Beslon B-15 
available from Toho Rayon Co., Ltd.; 15 denier) in stead of the 
polyacrylonitrile fiber of Example 1 (Cashmilon FCW BR of Asahi Chemical 
Industry Co., Ltd.; 15 denier). It was determined from the X-ray 
diffraction spectrum of the obtained carbonaceous material that an 
interval of 002 faces (i.e., maximum of the diffraction peak) was 3.42 
.ANG., length of a crystallite in c-axis direction was 100.8 .ANG., and 
the half width (2.theta.) of the diffraction peak was 0.72.degree.. 
Further, the magnetic resistance (.DELTA..rho./.rho.).sub.cr of the 
obtained carbonaceous material was confirmed to be negative. 
The prepared carbonaceous material was grained into particles of mean size 
25 .mu.m in the same manner as described in Example 1. Using this 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery 5). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
EXAMPLE 6 
A carbonaceous material was prepared in the same manner as described in 
Example 1 except for using another polyacrylonitrile fiber (Beslon B-5 
available from Toho Rayon Co., Ltd.; 5 denier) in stead of the 
polyacrylonitrile fiber of Example-1 (Cashmilon FCW BR available from 
Asahi Chemical Industry Co., Ltd.; 15 denier). It was determined from the 
X-ray diffraction spectrum of the obtained carbonaceous material that an 
interval of 002 faces (i.e., maximum of the diffraction peak) was 3.42 
.ANG., length of a crystallite in c-axis direction was 93.3 .ANG., and the 
half width (2.theta.) of the diffraction peak was 0.85.degree. . Further, 
the magnetic resistance (.DELTA..rho./.rho.).sub.cr of the obtained 
carbonaceous material was confirmed to be negative. 
The prepared carbonaceous material was grained into particles of mean size 
23 .mu.m in the same manner as described in Example 1. Using the 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery 6). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
EXAMPLE 7 
A carbonaceous material was prepared in the same manner as described in 
Example 1 except for performing the following step 4 using another 
polyacrylonitrile fiber in stead of the step 4 of Example 1. 
STEP 4: increasing temperature from room temperature to 3,200.degree. C. at 
the rate of 6.degree. C./minute, keeping the temperature of 3,200.degree. 
C. for 1 hour, and then cooling to room temperature for 36 hours. 
It was determined from the X-ray diffraction spectrum of the obtained 
carbonaceous material that an interval of 002 faces (i.e., maximum of the 
diffraction peak) was 3.42 .ANG., length of a crystallite in c-axis 
direction was 107.5 .ANG., and the half width (2.theta.) of the 
diffraction peak was 0.72.degree.. 
The prepared carbonaceous material was grained into particles of mean size 
22 .mu.m in the same manner as described in Example 1. Using the 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery 7). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
EXAMPLE 8 
A carbonaceous material was prepared in the same manner as described in 
Example 1 except for performing the following step 4 using another 
polyacrylonitrile fiber in stead of the step 4 of Example 1. 
STEP 4: increasing temperature from room temperature to 3,400.degree. C. at 
the rate of 6.degree. C./minute, keeping the temperature of 3,400.degree. 
C. for 1 hour, and then cooling to room temperature for 36 hours. 
It was determined from the X-ray diffraction spectrum of the obtained 
carbonaceous material that an interval of 002 faces (i.e., maximum of the 
diffraction peak) was 3.41 .ANG., length of a crystallite in c-axis 
direction was 125.3 .ANG., and the half width (2.theta.) of the 
diffraction peak was 0.72.degree.. 
The prepared carbonaceous material was grained into particles of mean size 
25 .mu.m in the same manner as described in Example 1. Using the 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery 8). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
EXAMPLE 9 
A carbonaceous material was prepared by burning polyacrylonitrile fiber 
(Cashmilon FCW BR of Asahi Chemical Industry Co., Ltd.; 15 denier) in the 
condition of no orientation in the following manner: 
STEP 1: step 1 was performed in the same manner as the step 1 of Example 1, 
STEP 2: increasing temperature in argon from room temperature to 
1,100.degree. C. at the rate of 15.degree. C./minute, keeping the 
temperature of 1,100.degree. C. for 1 hour, and then cooling to room 
temperature for 1 hours; by means of a muffle furnace (FP-31 available 
from Yamato Scientific Co., Ltd.), and 
STEP 3: increasing temperature from room temperature to 3,100.degree. C. at 
the rate of 6.degree. C./minute, keeping the temperature of 3,100.degree. 
C. for 1 hour, and then cooling to room temperature for 36 hours. 
It was determined from the X-ray diffraction spectrum of the obtained 
carbonaceous material that an interval of 002 faces (i.e., maximum of the 
diffraction peak) was 3.42 .ANG., length of a crystallite in c-axis 
direction was 104.9 .ANG., and the half width (2.theta.) of the 
diffraction peak was 0.77.degree.. 
The prepared carbonaceous material was grained into particles of mean size 
21 .mu.m in the same manner as described in Example 1. Using the 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery 9). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
COMISON EXAMPLE 1 
A carbonaceous material was prepared in the same manner as described in 
Example 1 except that STEP 4 was not carried out. 
X-ray diffraction spectrum of Cu-K.alpha. ray of the obtained carbonaceous 
material is shown in FIG. 3. It was determined from the X-ray diffraction 
spectrum of the obtained carbonaceous material that an interval of 002 
faces (i.e., maximum of the diffraction peak) was 3.47 .ANG., length of a 
crystallite in c-axis direction was 18.5 .ANG., and the half width 
(2.theta.) of the diffraction peak was 3.43.degree.. Further, the magnetic 
resistance (.DELTA..rho./.rho.).sub.cr of the obtained carbonaceous 
material was confirmed to be negative. 
The prepared carbonaceous material was grained into particles of mean size 
16 .mu.m in the same manner as described in Example 1. Using the 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery a). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
COMISON EXAMPLE 2 
A carbonaceous material was prepared in the same manner as described in 
Example 1 except for performing the following step 4 using another 
polyacrylonitrile fiber in stead of the step 4 of Example 1. 
STEP 4: increasing temperature from room temperature to 2,300.degree. C. at 
the rate of 6.degree. C./minute, keeping the temperature of 2,300.degree. 
C. for 1 hour, and then cooling to room temperature for 36 hours. 
X-ray diffraction spectrum of Cu-K.alpha. ray of the obtained carbonaceous 
material is shown in FIG. 4. It was determined from the X-ray diffraction 
spectrum of the obtained carbonaceous material that an interval of 002 
faces (i.e., maximum of the diffraction peak) was 3.47 .ANG., length of a 
crystallite in c-axis direction was 56.5 .ANG., and the half width 
(2.theta.) of the diffraction peak was 1.37.degree.. Further, the magnetic 
resistance (.DELTA..rho./.rho.).sub.cr of the obtained carbonaceous 
material was confirmed to be negative. 
The prepared carbonaceous material was grained into particles of mean size 
21 .mu.m in the same manner as described in Example 1. Using the 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery b). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
COMISON EXAMPLE3 
Using commercially available polyacrylonitrile carbon fiber (Toreca M-40 
available from Toray Industries, Inc.) in stead of the polyacrylonitrile 
fiber as starting material, a carbonaceous material was prepared. The 
starting material was burned single-stepwise in the manner of STEP 4 
described in Example 1. 
X-ray diffraction spectrum of Cu-K.alpha. ray of the obtained carbonaceous 
material is shown in FIG. 5. It was determined from the X-ray diffraction 
spectrum of the obtained carbonaceous material that an interval of 002 
faces (i.e., maximum of the diffraction peak) was 3.37 .ANG., length of a 
crystallite in c-axis direction was 176.1 .ANG., and the half width 
(2.theta.) of the diffraction peak was 0.58.degree.. Further, the magnetic 
resistance (.DELTA..rho./.rho.).sub.cr of the obtained carbonaceous 
material was confirmed to be negative. 
The prepared carbonaceous material was grained into particles of mean size 
27 .mu.m in the same manner as described in Example 1. Using the 
carbonaceous material powder, the procedures of Example 1 were repeated to 
prepare a secondary battery (Battery c). With respect to the obtained 
battery, the same test as described in Example 1 was carried out. 
The results of the charging-discharging test for the produced batteries are 
set forth in Table 3. 
TABLE 3 
______________________________________ 
Performance of Battery 
Capacity Loss*.sup.1) 
Capacity*.sup.2) 
Battery No. (mAH/g) (mAH/g) 
______________________________________ 
Example 1 Battery 1 105 195 
Example 2 Battery 2 110 175 
Example 3 Battery 3 108 190 
Example 4 Battery 4 127 187 
Example 5 Battery 5 98 205 
Example 6 Battery 6 120 190 
Example 7 Battery 7 96 201 
Example 8 Battery 8 93 209 
Example 9 Battery 9 131 183 
Comp.Ex.1 Battery a 368 115 
Comp.Ex.2 Battery b 238 125 
Comp.Ex.3 Battery c 518 118 
______________________________________ 
Notes: 
*.sup.1) measured after the 10th cycle was complete 
*.sup.2) measured at the 25th cycle 
The burning conditions and measured values of the carbonaceous materials 
for the anode active materials used for the batteries are also set forth 
in Tables 4A and 4B. 
TABLE 4A 
______________________________________ 
Burning Temp. X-ray diffraction 
Stage 3 Stage 4 d.sub.002 
L.sub.c 
Half Width 
Spec- 
Battery No. 
(.degree.C.) 
(.degree.C.) 
(.ANG.) 
(.ANG.) 
(degree) 
trum 
______________________________________ 
1 (Ex.1) 
1000 3000 3.42 98.2 0.77 FIG. 2 
2 (Ex.2) 
1000 3000 3.42 98.2 0.77 -- 
3 (Ex.3) 
1000 3000 3.42 98.2 0.77 -- 
4 (Ex.4) 
1000 3000 3.42 91.0 0.89 -- 
5 (Ex.5) 
1000 3000 3.42 100.8 0.72 -- 
6 (Ex.6) 
1000 3000 3.42 93.3 0.85 -- 
7 (Ex.7) 
1000 3200 3.42 107.5 0.72 -- 
8 (Ex.8) 
1000 3400 3.41 125.3 0.68 -- 
9 (Ex.9) 
3100 -- 3.42 104.9 0.77 -- 
a 1000 -- 3.47 18.5 3.43 FIG. 3 
(Com.Ex.1) 
b -- 2300 3.47 56.5 1.37 FIG. 4 
(Com.Ex.2) 
c -- 3000 3.37 176.5 0.58 FIG. 5 
(Com.Ex.3) 
______________________________________ 
TABLE 4B 
______________________________________ 
Magnetic Resistance 
Mean Grain Starting 
Battery No. 
(.DELTA..rho./.rho.).sub.cr (%) 
Size (.mu.m) 
Material 
______________________________________ 
1 (Ex.1) negative 18 fiber: 15 d 
2 (Ex.2) negative 18 fiber: 15 d 
3 (Ex.3) negative 18 fiber: 15 d 
4 (Ex.4) negative 25 fiber: 5 d 
5 (Ex.5) negative 25 fiber: 15 d 
6 (Ex.6) negative 23 fiber: 5 d 
7 (Ex.7) negative 22 fiber: 15 d 
8 (Ex.8) negative 25 fiber: 15 d 
9 (Ex.9) negative 21 fiber: 15 d 
a (Com.Ex.1) 
negative 16 fiber: 15 d 
b (Com.Ex.2) 
negative 21 fiber: 15 d 
c (Com.Ex.3) 
negative 27 carbon 
fiber*.sup.1) 
______________________________________ 
Notes: 
*.sup.1) polyacrylonitrile carbon fiber 
The carbonaceous materials (Examples 1-9) of the invention prepared by 
burning polyacrylonitrile fiber at a high temperature without orientation 
have specific characteristics determined from X-ray diffraction spectrum 
Cu-K.alpha. ray thereof. In more detail, the values of interval 
(d.sub.002) of 002 faces (i.e., maximum of the diffraction peak) were in 
the range of 3.41 to 3.42 .ANG., the values of length (Lc) of a 
crystallite in c-axis direction were in the range of 91 to 126 .ANG., the 
values of the half width (2.theta.) of the diffraction peak were in the 
range of 0.75 to 0.89.degree., and each diffraction peak was single in the 
range of 0.5 to 1.2.degree. (half width (2.theta.)). Further, the magnetic 
resistance (.DELTA..rho./.rho.).sub.cr was negative. 
Each of the batteries 1 to 9 having the anode containing the above 
carbonaceous materials is much superior to the Batteries "a" and "b", each 
of which comprises the anode containing the low-crystalline carbonaceous 
material burned at not more than 2,300.degree. C. of which diffraction 
peak (d.sub.002) is broad, from the viewpoint of both the 
charging-discharging capacity loss and the charging-discharging capacity. 
The battery "c" having the anode containing the burned material prepared by 
burning commercially available polyacrylonitrile carbon fiber at more than 
2,400.degree. C. shows high capacity loss and has small 
charging-discharging capacity. 
As is evident from the results of Examples and Comparison Examples, the 
battery of the invention using the anode active material of the 
carbonaceous material having the specific characteristics obtained from 
X-ray diffraction spectrum, which is prepared by burning polyacrylonitrile 
fiber multi-stepwise, is greatly improved in the charging-discharging 
capacity loss and charging-discharging capacity.