Positive electrode active substance particles and process for producing the same, and non-aqueous electrolyte secondary battery

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 50° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution and an aqueous sodium carbonate solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.2 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 105° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 830° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 2 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 350° C. for 5 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

As a result of subjecting the resulting positive electrode active substance particles to X-ray diffraction analysis, it was confirmed that the positive electrode active substance particles comprised a crystal system belonging to a space group of R-3m and a crystal system belonging to a space group of C2/m, and had a peak intensity ratio [(a)/(b)] of 0.071.

In addition, as a result of subjecting the resulting positive electrode active substance particles to ICP composition analysis, it was confirmed that the molar ratio of Li/(Ni+Co+Mn) was 1.32; the molar ratio of Ni:Co:Mn was 21.6:12.4:66 (i.e., the molar ratio of Mn/(Ni+Co+Mn) was 0.66); the boron (B) content was 0.092% by weight; the fluorine (F) content was 0.81% by weight; the aluminum (Al) content was 0.384% by weight; and the BET specific surface area as measured by a nitrogen absorption method was 3.5 m 2 /g. Further, as a result of observing the positive electrode active substance particles using a scanning electron microscope (SEM), it was recognized that primary particles thereof having an average primary particle diameter of 0.07 μm were aggregated together to form secondary particles having an average secondary particle diameter of 12.1 μm.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.4 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 105° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 920° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 25° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 85° C. for 1 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 400° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 60° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.1 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 110° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid and aluminum fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 850° C. for 7 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 45° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.1 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles, boric acid, lithium fluoride and aluminum hydroxide were weighed and intimately mixed with each other. The resulting mixture was calcined at 900° C. for 5 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 55° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.4 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water. Into the filter cake comprising the thus obtained co-precipitated precursor were added an aqueous boric acid solution, an aqueous ammonium fluoride solution and an aqueous aluminum nitrate solution, and the resulting mixture was intimately kneaded and dried at 105° C. overnight, thereby obtaining dried particles.

The thus obtained dried particles and lithium carbonate particles were weighed and intimately mixed with each other. The resulting mixture was calcined at 780° C. for 10 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 60° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.1 (±0.2). During the reaction, while the reaction slurry was overflowed, the slurry was sequentially discharged out of the reaction system, and the slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles, boric acid and aluminum fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 1250° C. for 1 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 50° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.1 (±0.2). During the reaction, while the reaction slurry was overflowed, the slurry was sequentially discharged out of the reaction system, and the slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 870° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 3 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 250° C. for 5 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.0 (±0.1). During the reaction, while the reaction slurry was overflowed, the slurry was sequentially discharged out of the reaction system, and the slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 690° C. for 15 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 15° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 3 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 550° C. for 2 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 70° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-nitrate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.2 (±0.2). During the reaction, while the reaction slurry was overflowed, the slurry was sequentially discharged out of the reaction system, and the slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium nitrate particles, diboron trioxide, lithium fluoride and alumina were weighed and intimately mixed with each other. The resulting mixture was calcined at 1100° C. for 2 hr under an oxygen flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 9.3 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid and magnesium fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 910° C. for 5 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 50° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution and an aqueous sodium carbonate solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 9.0 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 850° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous magnesium nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 3 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 60° C. overnight and then subjected to heat treatment at 150° C. for 10 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 10.2 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 900° C. for 5 hr under an air flow using an electric furnace.

The resulting calcined product and titanium fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 150° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 50° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.5 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 830° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous titanium nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 2 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 100° C. overnight and then subjected to heat treatment at 400° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.2 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 900° C. for 5 hr under an air flow using an electric furnace.

The resulting calcined product and zirconium fluoride were weighed and intimately mixed with each other. The resulting mixture was subjected to heat treatment at 150° C. for 5 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 55° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-nitrate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.1 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, diboron trioxide and calcium fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 840° C. for 10 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 50° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-chloride mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.5 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 120° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium nitrate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 920° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous ferric nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 3 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 100° C. overnight and then subjected to heat treatment at 250° C. for 2 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 50° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and a lithium carbonate slurry were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.2 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 810° C. for 5 hr under an air flow using an electric furnace.

The resulting calcined product and zinc fluoride were weighed and intimately mixed with each other. The resulting mixture was subjected to heat treatment at 300° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 35° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-chloride mixed aqueous solution, an aqueous lithium hydroxide solution and an aqueous hydrazine solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.3 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles, boric acid, lithium fluoride and lithium molybdate were weighed and intimately mixed with each other. The resulting mixture was calcined at 910° C. for 5 hr under an oxygen flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 55° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution and an aqueous sodium carbonate solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.3 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid, lithium fluoride and bismuth oxide were weighed and intimately mixed with each other. The resulting mixture was calcined at 830° C. for 7 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 30° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.1 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid, magnesium fluoride and aluminum fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 910° C. for 7 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 60° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution and an aqueous sodium carbonate solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.5 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 105° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid and magnesium hydroxide were weighed and intimately mixed with each other. The resulting mixture was calcined at 820° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 25° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 85° C. for 1 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 400° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.5 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 105° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid and titanium oxide were weighed and intimately mixed with each other. The resulting mixture was calcined at 930° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 3 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 400° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution and an aqueous sodium carbonate solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.5 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid, magnesium hydroxide and titanium oxide were weighed and intimately mixed with each other. The resulting mixture was calcined at 850° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 3 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 350° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.4 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid, lithium fluoride, aluminum fluoride, magnesium hydroxide and titanium oxide were weighed and intimately mixed with each other. The resulting mixture was calcined at 920° C. for 4 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 60° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-nitrate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.2 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium nitrate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 920° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 75° C. for 3 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 350° C. for 5 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 60° C. while flowing a nitrogen gas therethrough. Further, a Co- and Mn-nitrate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.4 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium nitrate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 910° C. for 6 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 10° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 1 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 400° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 70° C. while flowing a nitrogen gas therethrough. Further, a Ni- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.1 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 900° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 20° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 80° C. for 1 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 300° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 45° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution and an aqueous sodium carbonate solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.4 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 105° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 840° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous ammonium fluoride solution, and while stirring at 20° C., an aqueous aluminum nitrate solution was added dropwise thereinto, thereby obtaining a slurry. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 380° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.4 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 105° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 910° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous ammonium fluoride solution, and while stirring at 25° C., an aqueous aluminum nitrate solution was added dropwise thereinto, thereby obtaining a slurry. The thus obtained slurry was filtered, and the resulting solid was dried at 100° C. overnight and then subjected to heat treatment at 400° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

Comparative Example 1

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution and an aqueous sodium carbonate solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.1 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid and aluminum fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 900° C. for 5 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

Comparative Example 2

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 60° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.0 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid and magnesium fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 950° C. for 10 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

Comparative Example 3

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 50° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.2 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor and lithium carbonate particles were weighed and intimately mixed with each other. The resulting mixture was calcined at 850° C. for 5 hr under an air flow using an electric furnace.

The thus obtained calcined product and zinc fluoride were weighed and intimately mixed with each other. The resulting mixture was subjected to heat treatment at 400° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

Comparative Example 4

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.2 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 850° C. for 5 hr under an air flow using an electric furnace.

The thus obtained calcined product and titanium fluoride were weighed and intimately mixed with each other. The resulting mixture was subjected to heat treatment at 150° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

Comparative Example 5

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 50° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution and an aqueous sodium carbonate solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.5 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles, boric acid and aluminum hydroxide were weighed and intimately mixed with each other. The resulting mixture was calcined at 830° C. for 10 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

Comparative Example 6

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 40° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium hydroxide solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 11.4 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 105° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium carbonate particles and boric acid were weighed and intimately mixed with each other. The resulting mixture was calcined at 810° C. for 5 hr under an air flow using an electric furnace.

Next, the resulting calcined product was charged into an aqueous aluminum nitrate solution, and while stirring at 15° C., an ammonium fluoride solution was added dropwise thereinto, followed by maintaining the resulting solution at 70° C. for 10 hr. The thus obtained slurry was filtered, and the resulting solid was dried at 105° C. overnight and then subjected to heat treatment at 500° C. for 3 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

Comparative Example 7

A closed type reaction vessel was charged with 14 L of water, and an inside of the reaction vessel was maintained at 60° C. while flowing a nitrogen gas therethrough. Further, a Ni-, Co- and Mn-sulfate mixed aqueous solution, an aqueous sodium carbonate solution and an aqueous ammonia solution were successively added into the reaction vessel while stirring such that the pH value therein was adjusted to 8.3 (±0.2). During the reaction, a filtrate only was discharged out of the reaction system using a concentration device, whereas a solid component separated from the filtrate was retained in the reaction vessel. After completion of the reaction, a slurry comprising a co-precipitated product was obtained. The thus obtained slurry was filtered, and the resulting solid was washed with water and dried at 100° C. overnight, thereby obtaining a co-precipitated precursor in the form of particles.

The thus obtained co-precipitated precursor, lithium hydroxide particles, boric acid and lithium fluoride were weighed and intimately mixed with each other. The resulting mixture was calcined at 880° C. for 7 hr under an air flow using an electric furnace, thereby obtaining positive electrode active substance particles.

Various properties of the positive electrode active substance particles obtained in Examples 1 to 29 and Comparative Examples 1 to 7 are shown in Table 1, and various properties of batteries produced using the positive electrode active substance particles are shown in Table 2.

In any of the positive electrode active substance particles obtained in Examples 1 to 29, the 3rd cycle discharge capacity thereof was not less than 190 mA/g, and the ratio in percent of the 32nd cycle discharge capacity to the 3rd cycle discharge capacity was not less than 85%. Thus, it was confirmed that the positive electrode active substance particles obtained according to the present invention had a large discharge capacity owing to the presence of the crystal structure belonging to a space group of 2C/m, and further the reaction thereof with an electrolyte solution upon charging and discharging and upon heating was suppressed owing to the boron, fluorine and element A added thereto. Therefore, the positive electrode active substance particles according to the present were positive electrode materials having a high discharge capacity as well as excellent cycle characteristics and thermal stability.

On the other hand, the positive electrode active substance particles obtained in Comparative Examples which failed to comprise boron, fluorine and the element A in an adequate amount were deteriorated in thermal stability and/or cycle characteristics as compared those obtained in Examples. However, it was recognized that if boron, fluorine and the element A were allowed to coexist in an adequate amount in the positive electrode active substance particles, it was possible to obtain positive electrode active substance particles for non-aqueous electrolyte secondary batteries having a high discharge capacity as well as excellent thermal stability and cycle characteristics.

From the above results, it was confirmed that the positive electrode active substance particles according to the present invention exhibited large charge/discharge capacities as well as excellent cycle characteristics and thermal stability, and therefore were useful as a positive electrode active substance particles for non-aqueous electrolyte secondary batteries.