Title of Invention	"A PROCESS FOR THE PREPARATION OF OLIVINE LITHIUM NICKEL PHOSPHATE COMPOSITE, SAID PROSESS"
Abstract	The present invention relates to a process for the preparation of olivine lithium nickel phosphate (LiNiPO4) composite, which is very useful for high voltage lithium reversible cells. LiNiPO4) is a reversible cathode material useful for high voltage cells of lithium in non-aqueous media.The prepared product was subjected to x-ray analysis. The product was found to be in single phase. Olivine lithium nickel phosphate composite is prepared by mixing oxides of nickel, phosphorous with lithium carbonate and heating together all in solid state condition.

Title of Invention

"A PROCESS FOR THE PREPARATION OF OLIVINE LITHIUM NICKEL PHOSPHATE COMPOSITE, SAID PROSESS"

Abstract

The present invention relates to a process for the preparation of olivine lithium nickel phosphate (LiNiPO4) composite, which is very useful for high voltage lithium reversible cells. LiNiPO4) is a reversible cathode material useful for high voltage cells of lithium in non-aqueous media.The prepared product was subjected to x-ray analysis. The product was found to be in single phase. Olivine lithium nickel phosphate composite is prepared by mixing oxides of nickel, phosphorous with lithium carbonate and heating together all in solid state condition.

Full Text	PROCESS FOR THE PREPARATION OF OLIVINE LITHIUM NICKEL PHOSPHATE COMPOSITE. Field of the invention The present invention relates to a process for the preparation of olivine lithium nickel phosphate (LiNiPO4) composite, which is very useful for high voltage lithium reversible cells. LiNiPO4) is a reversible cathode material useful for high voltage cells of lithium in non-aqueous media. Background of the invention In all the procedures available in the literature several disadvantages are observed. 1. Phase impurity 2. Longer duration of thermal preparation 3. High temperature of operation 4. pH control 5. Several steps of preparation. Objects of the invention The main object of this invention is to synthesis olivine LiNiPO4 under suitable solid state reaction method which obviates the defects and draw backs hither to known in other methods of preparation of this compound from already known procedures in literatures. Brief description of the accompanying drawings Figure 1 shows the X-ray analysis confirming the formation of LiNiPO4. Summary of the invention Accordingly the present invention provides a process for the production of olivine lithium nickel phosphate composite, said process comprising characterized in that uniformly mixing oxides of Ni and P with Li2CO3, in a molar ratio 1:1:1, converting the mixture to a paste by adding glycerol, adding flux slowly under heating, calcining the paste so obtained to a temperature of up to 800°C continuously for a period of up to 12 hours to obtain the desired composite. In on embodiment of the invention, the oxide of phosphorous is P2O5 In a further embodiment of the invention, the nickel oxide is NiO. In another embodiment of the invention, the calcinations is done in a furnace. Detailed description of the invention The prepared product was subjected to x-ray analysis. The product was found to be in single phase. Olivine lithium nickel phosphate composite is prepared by mixing oxides of nickel, phosphorous with lithium carbonate and heating together all in solid state condition. The cathode material is synthesized for a secondary battery, by heating a paste prepared by mixing fine particles of Li2CO3, P2O4 and NiO in glycerol. This paste was initially heated slowly in a furnace to evaporate off glycerol in order to get a dried mass at 250°C. This dried mass was then continuously heated to 750°C for 12 hrs. The compound formed was slowly cooled to room temperature and was ground well and then examined for its particle size, colour and XRD exposure. It was found that the prepared sample was purple in colour and was homogenous. X-rays analysis confirmed the formation of LiNiPC>4 according to Fig. 1. The following examples give the way of synthesising LiNiPO4 Example -1 Li2CO3, NiO and P205 in the molar ratio of 1:1:1 (0.74 gm; 1.49 gm and 1.42 gm respectively) were mixed slowly in glycerol binder (2ml). Flux (urea in an amount of 2.402 gm) was added slowly under heating up to a temperature of 800°C for a period of upto 10 hours. The mixture was then cooled to room temperature and the residue subjected to XRD exposure. The purple coloured product confirmed the production of olivine lithium nickel phosphate (UMPO4) composite. The efficiency of the reaction was 90% and the product was obtained in single phase. Single electrode potential of LiNiPO4 with respect to Li in 1M LiClO4 in propylene carbonate was 2.99 v. Example - 2 Li2C03, NiO and P2O5 in the molar ratio of 1:1:1 (0.74 gm; 1,49 gm and 1.42 gm respectively) were mixed slowly in glycerol binder (3ml). Flux (urea in an amount of 2.402 gm) was added slowly under heating up to a temperature of 600°C for a period of upto 12 hours. The mixture was then cooled to room temperature and the residue subjected to XRD exposure. The purple coloured product confirmed the production of olivine lithium nickel phosphate (LiNiPO4) composite. The efficiency of the reaction was 90% and the product was obtained in single phase. Single electrode potential of LiNiPO4 with respect to Li in 1M LiClC>4 in propylene carbonate was 2.99 v. The advantages of the invention are 1. Fine particles of the reactants viz. Li2CO3, NiO and P2O5 were bound by glycerol and made the mixture into a paste uniform reaction during heating. 2. Glycerol is used as a binder for the inorganic solid state reactants 3. The product LiNiPO4 is obtained in a single phase component free from impurities as evidenced by x-ray analysis. 4. All the reactants react uniformly leaving no unreacted initial reactant components. 5. Addition of glycerol as a binder has no influence in the formation of the final product. 6 A uniform homogeneous mixture of oxides of phosphorous (P2O5) and nickel with Li2CO3 were made into a paste to get a product of high purity. 7. Glycerol used as a solvent for binding the oxides viz. phosphorous and nickel with Li2CO3 for making a paste of required consistency also enhanced the product of fine particles. 8. The addition of a flux (urea) and excess addition of glycerol (solvent) as a binding material for oxides does not change the colour or quality of the end product. We Claim: 1. A process for the production of olivine lithium nickel phosphate composite, said process comprising characterized in that uniformly mixing oxides of Ni and P with Li2CO3, in a molar ratio 1:1:1, converting the mixture to a paste by adding glycerol, adding flux slowly under heating, calcining the paste so obtained to a temperature of up to 800°C continuously for a period of up to 12 hours to obtain the desired composite. 2. A process as claimed in claim 1 wherein the oxide of phosphorous is PaOs. 3. A process as claimed in claims 1 and 2 wherein the nickel oxide is NiO. 4. A process as claimed in any preceding claim wherein the calcinations is done in a furnace. 5. A process as claimed in any preceding claim wherein urea is used as a flux. 6. A process for the production of olivine lithium nickel phosphate composite substantially as described hereinbefore and with reference to the foregoing examples and the accompanying drawing.

Full Text

PROCESS FOR THE PREPARATION OF OLIVINE LITHIUM NICKEL PHOSPHATE COMPOSITE. Field of the invention
The present invention relates to a process for the preparation of olivine lithium nickel phosphate (LiNiPO4) composite, which is very useful for high voltage lithium reversible cells. LiNiPO4) is a reversible cathode material useful for high voltage cells of lithium in non-aqueous media. Background of the invention
In all the procedures available in the literature several disadvantages are observed.
1. Phase impurity
2. Longer duration of thermal preparation
3. High temperature of operation
4. pH control
5. Several steps of preparation.
Objects of the invention
The main object of this invention is to synthesis olivine LiNiPO4 under suitable solid state reaction method which obviates the defects and draw backs hither to known in other methods of preparation of this compound from already known procedures in literatures.
Brief description of the accompanying drawings
Figure 1 shows the X-ray analysis confirming the formation of LiNiPO4. Summary of the invention
Accordingly the present invention provides a process for the production of olivine
lithium nickel phosphate composite, said process comprising characterized in that uniformly mixing oxides of Ni and P with Li2CO3, in a molar ratio 1:1:1, converting the mixture to a paste by adding glycerol, adding flux slowly under heating, calcining the paste so obtained to a temperature of up to 800°C continuously for a period of up to 12 hours to obtain the desired composite.
In on embodiment of the invention, the oxide of phosphorous is P2O5
In a further embodiment of the invention, the nickel oxide is NiO.
In another embodiment of the invention, the calcinations is done in a furnace.
Detailed description of the invention
The prepared product was subjected to x-ray analysis. The product was found to be in
single phase. Olivine lithium nickel phosphate composite is prepared by mixing oxides
of nickel, phosphorous with lithium carbonate and heating together all in solid state
condition.
The cathode material is synthesized for a secondary battery, by heating a paste prepared by mixing fine particles of Li2CO3, P2O4 and NiO in glycerol. This paste was

initially heated slowly in a furnace to evaporate off glycerol in order to get a dried mass at 250°C. This dried mass was then continuously heated to 750°C for 12 hrs. The compound formed was slowly cooled to room temperature and was ground well and then examined for its particle size, colour and XRD exposure. It was found that the prepared sample was purple in colour and was homogenous. X-rays analysis confirmed the formation of LiNiPC>4 according to Fig. 1.
The following examples give the way of synthesising LiNiPO4 Example -1
Li2CO3, NiO and P205 in the molar ratio of 1:1:1 (0.74 gm; 1.49 gm and 1.42 gm respectively) were mixed slowly in glycerol binder (2ml). Flux (urea in an amount of 2.402 gm) was added slowly under heating up to a temperature of 800°C for a period of upto 10 hours. The mixture was then cooled to room temperature and the residue subjected to XRD exposure. The purple coloured product confirmed the production of olivine lithium nickel phosphate (UMPO4) composite. The efficiency of the reaction was 90% and the product was obtained in single phase. Single electrode potential of LiNiPO4 with respect to Li in 1M LiClO4 in propylene carbonate was 2.99 v. Example - 2
Li2C03, NiO and P2O5 in the molar ratio of 1:1:1 (0.74 gm; 1,49 gm and 1.42 gm respectively) were mixed slowly in glycerol binder (3ml). Flux (urea in an amount of 2.402 gm) was added slowly under heating up to a temperature of 600°C for a period of upto 12 hours. The mixture was then cooled to room temperature and the residue subjected to XRD exposure. The purple coloured product confirmed the production of olivine lithium nickel phosphate (LiNiPO4) composite. The efficiency of the reaction was 90% and the product was obtained in single phase. Single electrode potential of LiNiPO4 with respect to Li in 1M LiClC>4 in propylene carbonate was 2.99 v. The advantages of the invention are
1. Fine particles of the reactants viz. Li2CO3, NiO and P2O5 were bound by glycerol and
made the mixture into a paste uniform reaction during heating.
2. Glycerol is used as a binder for the inorganic solid state reactants
3. The product LiNiPO4 is obtained in a single phase component free from impurities as
evidenced by x-ray analysis.
4. All the reactants react uniformly leaving no unreacted initial reactant components.
5. Addition of glycerol as a binder has no influence in the formation of the final product.

6 A uniform homogeneous mixture of oxides of phosphorous (P2O5) and nickel with Li2CO3 were made into a paste to get a product of high purity.
7. Glycerol used as a solvent for binding the oxides viz. phosphorous and nickel with
Li2CO3 for making a paste of required consistency also enhanced the product of fine
particles.
8. The addition of a flux (urea) and excess addition of glycerol (solvent) as a binding
material for oxides does not change the colour or quality of the end product.

We Claim:
1. A process for the production of olivine lithium nickel phosphate composite, said
process comprising characterized in that uniformly mixing oxides of Ni and P
with Li2CO3, in a molar ratio 1:1:1, converting the mixture to a paste by adding
glycerol, adding flux slowly under heating, calcining the paste so obtained to a
temperature of up to 800°C continuously for a period of up to 12 hours to obtain
the desired composite.
2. A process as claimed in claim 1 wherein the oxide of phosphorous is PaOs.
3. A process as claimed in claims 1 and 2 wherein the nickel oxide is NiO.
4. A process as claimed in any preceding claim wherein the calcinations is done in a
furnace.
5. A process as claimed in any preceding claim wherein urea is used as a flux.
6. A process for the production of olivine lithium nickel phosphate composite
substantially as described hereinbefore and with reference to the foregoing
examples and the accompanying drawing.

Documents:

481-del-2001-abstract.pdf

481-del-2001-claims.pdf

481-del-2001-complete specification (granted).pdf

481-del-2001-correspondence-others.pdf

481-del-2001-correspondence-po.pdf

481-del-2001-description (complete).pdf

481-del-2001-drawings.pdf

481-del-2001-form-1.pdf

481-del-2001-form-18.pdf

481-del-2001-form-2.pdf

481-del-2001-form-3.pdf

481-del-2001-petition-137.pdf

481-del-2001-petition-138.pdf

« Previous Patent

Next Patent »

Patent Number

227538

Indian Patent Application Number

481/DEL/2001

PG Journal Number

13/2009

Publication Date

27-Mar-2009

Grant Date

13-Jan-2009

Date of Filing

12-Apr-2001

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH,

Applicant Address

RAFI MARG, NEW DELHI-110001, INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	ANGAIAH SUBRAMANIAN	EXT. SRF, DEPT. OF INDUSTRIAL CHEMESTRY ALAGAPPA UNIVERSITY, KARAKUDI 630003,
2	ARIYANAN MANI, SCIENTIST	CECRI, KARAIKUDI 630006.
3	THIAGARAJAN VASUDEVAN	PROF. & HEAD. ALAGAPPA UNIVERSITY, KARAIKUDI 630003, INDIA.
4	RAMAIYER GANGADHARAN,	EMERITUS SCIENTIST, ALAGAPPA UNIVERSITY, KARAIKUDI 630003, INDIA

PCT International Classification Number

C01B 25/45

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA