Title of Invention	"A NOVEL PROCESS FOR THE SYNTHESIS OF LITHIUM COBALT NICKLE VANADATE (LiCo1/2 Ni1/2VO4) AS CATHODE MATERIAL FOR HIGH VOLTAGE LITHIUM ION CELLS"
Abstract	A novel process for the synthesis of lithium cobalt nickel vanadate (LiCo1/2Ni1/2 V04) as cathode material for high voltage lithium ion cells which comprises by mixing lithium oxides, cobalt oxide, nickel oxide & vanadium oxide in molar ratios of 1 : 1/2 : 1/2 : 1 respectively and then preparing a paste by adding binding agent, heating the above paste upto 750°C for a maximum period of 12 hours and then, cooling the product to get lithium cobalt nickel vanadate (LiCo1/2Ni1/2 V04)

Title of Invention

"A NOVEL PROCESS FOR THE SYNTHESIS OF LITHIUM COBALT NICKLE VANADATE (LiCo1/2 Ni1/2VO4) AS CATHODE MATERIAL FOR HIGH VOLTAGE LITHIUM ION CELLS"

Abstract

A novel process for the synthesis of lithium cobalt nickel vanadate (LiCo1/2Ni1/2 V04) as cathode material for high voltage lithium ion cells which comprises by mixing lithium oxides, cobalt oxide, nickel oxide & vanadium oxide in molar ratios of 1 : 1/2 : 1/2 : 1 respectively and then preparing a paste by adding binding agent, heating the above paste upto 750°C for a maximum period of 12 hours and then, cooling the product to get lithium cobalt nickel vanadate (LiCo1/2Ni1/2 V04)

Full Text	The present invention relates to the novel process for the preparation of lithium cobalt nickel vanadate useful as : cathode material for lithium ion cells. The present invention more particularly relates to the preparation of lithium cobalt nickel vanadate (LiCoo.sNio.5VO4) a composite by mixing oxides of cobalt, nickel & vanadium with lithium hydroxide by solid state reaction. Cobalt nickel vanadate of lithium is useful as a positive electrode material for reversible rechargeable secondary cells based on lithium. Studies on the inverse spinel LiCo1/2 Ni1/2VO4 can be traced back 1997 onwards. It was already established that this spinel compound was able to intercalate/deintercalate in a nonaqueous medium when used as an electrode in a lithium battery. This compound was prepared by a solution coprecipitation of LiOH, Ni(NO3)2, Co(NO3)2 and NH4VO3 followed by heating the precipitate at 500°C for 48 hours.[G T K Fey, K.S. Wang and S M Yang, J Power Sources, 68 (1997)159] In the above procedure, any one of the following disadvantages are observed. 1. Particle size 2. Longer duration of thermal preparation 3. Controlling of pH & temperature etc. The object of this invention is to synthesis lithium cobalt nickel vanadate cathode material by solid state reaction procedure which obviates the defects and drawbacks hither to known in other methods of preparation of this compound from the known procedures available in literature. The main object of this present invention is to formulate a new procedure for the synthesis of a novel wet grinding method for the synthesis of LiCo0.5 Ni0.5VO4 cathode material for high voltage lithium ion cells which obviates the drawbacks of the known methods. Further object of this invention is cyclability of this system by retaining Co in the cathode material and replacing a parts of it by Ni. Still another object is to use glycerol as binding agent to make an uniform homogeneous mixture which permits uniform reaction to occur without any side reactions. Yet another object of this invention is to prepare LiCo0.5 Ni0.5VO4 from various oxides. A novel method of preparing this compound viz., LiCo1/2 Ni1/2 VO4VO4 was carried out by uniform mixing of oxides of Li, Co, Ni and vanadium and this mixture was made into a paste by adding necessary quantity of glycerol and the paste was calcined at 750°C continuously for 12 hrs in a furnace. The prepared product was subjected to X-ray analysis. The product was found to be in single phase. The present invention, describes the method of synthesis of the cathode material for a secondary battery, by heating a paste prepared by mixing fine particles of Li2Os, Co3O4, NiO and V205 made in glycerol. This paste was initially heated slowly in a furnace to evaporate off glycerol in order to get a dried mass at 150- 250°C. This dried mass was then continuously heated to 750°C for 12 hrs. The product formed was slowly cooled to room temperature and was ground well and then examined for its particles size, colour and XRD exposure. It was found that the prepared sample was blackish brown in coloured and was homogeneous. X-rays analysis confirmed the formation of LiCoi/2Nii/2 V04 according to Fig 1 and Table 1. Accordingly the present invention provides a novel process for the synthesis of lithium cobalt nickel vanadate (LiCoi/2Nii/2 V04) as cathode material for high voltage lithium ion cells which comprises by mixing lithium oxides, cobalt oxide, nickel oxide & vanadium oxide in molar ratios of 1 : 1/2 : 1/2 : 1 respectively and then preparing a paste by adding binding agent, heating the above paste upto 750°C for a maximum period of 12 hours and then, cooling the product to get lithium cobalt nickel vanadate (LiCo1/2Ni1/2 V04). In one of the embodiment of this invention the molar ratio Li: Co : Ni: V may be 1:1/2: 1/2 : 1. In another embodiment of this invention the temperature of preparation of this compound may be in between 150°C to 750°C. In yet another embodiment of this invention glycerol is used as a binding agent for uniform product formation. This prevents any side reaction & partial reaction. The novelty of this process lies in the following aspects: This method yields pure products without under going side reactions of partial reactions because of use of glycerol as binding agent. Partial sizes are found to be superior compared to other process which will be useful for better purposes because of increased geometrical area of the surface.Thermal heating shorter than the other procedures. The following examples are given by the way of illustration and should not be construed the scope of this invention. The following examples illustration the synthesis of LiCoi/2Nii/2VO4 cathode material by solid state reaction. Example -1 Components Li2O 0.30 gm Co3O4 0.80 gm NiO 0.75 gm V205 1.82gm Binder (Glycerol) 2 ml Temperature 150°C - 750°C Duration of heating 12 hrs Colour of the product brown Efficiency of the product 96% Phase Single Single electrode potential of LiCo1/2Ni1/2 V04. w.r.t. Li in 1MliClO4 3.0lv In propylene carbonate. A standard procedure in followed to measure the single electrode potential of the cathode. Oxides of lithium, cobalt, nickel & vanadium were ground well in a pestle / mortar arrangement. After grinding the powder was mixed with glycerol & ground well to obtain a paste. This paste was then heated initially slowly up to 250°C & finally to 750°C for 12 hours. The product obtained was cooled & than ground well & x-rays for confirmation of this product. Example - 2 Components Li2O 0.30 gm Co304 0.80 gm NiO 0.75 gm V2O5 1.82gm Binder (Glycerol) 4 ml Temperature 200°C - 750°C Duration of heating 10 hrs Colour of the product brown Efficiency of the product 96% Phase Single Single electrode potential of LiCo1/2Ni1/2 V04w.r.t. Li in 1MHC1O4 3.01v In propylene carbonate. A standard procedure is followed to measure the single electrode potential of the cathode. Process is same as described in example 1. The following advantages are claimed in this invention for the preparation of lithium cobalt nickel vanadate. An uniform homogeneous mixture of the reacting components viz., oxides of lithium, cobalt, nickel and vanadium were made into a paste to get a product of high purity. Glycerol was used as a solvent for binding the oxides viz., cobalt, nickel, vanadium and lithium for making a paste of required consistency. The addition of glycerol enhanced the product of fine particles. The excess addition of glycerol (solvent) as a binding material for the oxides does not change the colour or quality of the end product. Since pure oxides are used in fine form and homogenously prepared paste was obtained, calcinations of the compound leaves all the reactants to react uniformly to get fine resultant product without leaving any unreacted initial components. We claim: 1. A novel process for the synthesis of lithium cobalt nickel vanadate (LiCo1/2Ni1/2 V04) as cathode material for high voltage lithium ion cells which comprises by mixing lithium oxides, cobalt oxide, nickel oxide & vanadium oxide in molar ratios of 1 : 1/2 : 1/2 : 1 respectively and then preparing a paste by adding binding agent, heating the above paste upto 750°C for a maximum period of 12 hours and then, cooling the product to get lithium cobalt nickel vanadate (LiCo1/2Ni1/2V04). 2. A novel processas claimed in 1 claim wherein all reactants react uniformly. 3.. A novel processas claimed in claimsl-2 wherein glycerol in used as binding agent to form a paste with the reactants viz., oxides of cobalt, nickel, vanadium with Li2O. 4. A novel processas claimed in claims 1-3 wherein process produces a single phase LiCo1/2Ni1/2V04 free from impurity. 5. A novel processas claimed in claims 1-4 wherein heating is effected in between 150-750°C in a furnace makes all the reactants to react uniformly leaving no initial reactant left un-reacted. 6. A novel process for the synthesis of lithium cobalt nickel vanadate (LiCo1/2Ni1/2 V04) cathode material for high voltage lithium ion cells as herein described with reference to the examples.

Full Text

The present invention relates to the novel process for the preparation of lithium cobalt nickel vanadate useful as : cathode material for lithium ion cells. The present invention more particularly relates to the preparation of lithium cobalt nickel vanadate (LiCoo.sNio.5VO4) a composite by mixing oxides of cobalt, nickel & vanadium with lithium hydroxide by solid state reaction. Cobalt nickel vanadate of lithium is useful as a positive electrode material for reversible rechargeable secondary cells based on lithium.
Studies on the inverse spinel LiCo1/2 Ni1/2VO4 can be traced back 1997 onwards. It was already established that this spinel compound was able to intercalate/deintercalate in a nonaqueous medium when used as an electrode in a lithium battery. This compound was prepared by a solution coprecipitation of LiOH, Ni(NO3)2, Co(NO3)2 and NH4VO3 followed by heating the precipitate at 500°C for 48 hours.[G T K Fey, K.S. Wang and S M Yang, J Power Sources, 68 (1997)159] In the above procedure, any one of the following disadvantages are observed.
1. Particle size
2. Longer duration of thermal preparation
3. Controlling of pH & temperature etc.
The object of this invention is to synthesis lithium cobalt nickel vanadate cathode material by solid state reaction procedure which obviates the defects and drawbacks hither to known in other methods of preparation of this compound from the known procedures available in literature.

The main object of this present invention is to formulate a new procedure for the synthesis of a novel wet grinding method for the synthesis of LiCo0.5 Ni0.5VO4 cathode material for high voltage lithium ion cells which obviates the drawbacks of the known methods.
Further object of this invention is cyclability of this system by retaining Co in the cathode material and replacing a parts of it by Ni.
Still another object is to use glycerol as binding agent to make an uniform homogeneous mixture which permits uniform reaction to occur without any side reactions.
Yet another object of this invention is to prepare LiCo0.5 Ni0.5VO4 from various oxides.
A novel method of preparing this compound viz., LiCo1/2 Ni1/2 VO4VO4 was carried out by uniform mixing of oxides of Li, Co, Ni and vanadium and this mixture was made into a paste by adding necessary quantity of glycerol and the paste was calcined at 750°C continuously for 12 hrs in a furnace. The prepared product was subjected to X-ray analysis. The product was found to be in single phase.
The present invention, describes the method of synthesis of the cathode material for a secondary battery, by heating a paste prepared by mixing fine particles of Li2Os, Co3O4, NiO and V205 made in glycerol. This paste was initially heated slowly in a furnace to evaporate off glycerol in order to get a dried mass at 150-

250°C. This dried mass was then continuously heated to 750°C for 12 hrs. The product formed was slowly cooled to room temperature and was ground well and then examined for its particles size, colour and XRD exposure. It was found that the prepared sample was blackish brown in coloured and was homogeneous. X-rays analysis confirmed the formation of LiCoi/2Nii/2 V04 according to Fig 1 and Table 1.
Accordingly the present invention provides a novel process for the synthesis of lithium cobalt nickel vanadate (LiCoi/2Nii/2 V04) as cathode material for high voltage lithium ion cells which comprises by mixing lithium oxides, cobalt oxide, nickel oxide & vanadium oxide in molar ratios of 1 : 1/2 : 1/2 : 1 respectively and then preparing a paste by adding binding agent, heating the above paste upto 750°C for a maximum period of 12 hours and then, cooling the product to get lithium cobalt nickel vanadate (LiCo1/2Ni1/2 V04).
In one of the embodiment of this invention the molar ratio Li: Co : Ni: V may be
1:1/2: 1/2 : 1.
In another embodiment of this invention the temperature of preparation of this compound may be in between 150°C to 750°C.
In yet another embodiment of this invention glycerol is used as a binding agent for uniform product formation. This prevents any side reaction & partial reaction.
The novelty of this process lies in the following aspects:
This method yields pure products without under going side reactions of partial
reactions because of use of glycerol as binding agent.

Partial sizes are found to be superior compared to other process which will be useful for better purposes because of increased geometrical area of the surface.Thermal heating shorter than the other procedures.
The following examples are given by the way of illustration and should not be construed the scope of this invention.
The following examples illustration the synthesis of LiCoi/2Nii/2VO4 cathode material by solid state reaction.
Example -1 Components
Li2O 0.30 gm
Co3O4 0.80 gm
NiO 0.75 gm
V205 1.82gm
Binder (Glycerol) 2 ml
Temperature 150°C - 750°C
Duration of heating 12 hrs
Colour of the product brown
Efficiency of the product 96%
Phase Single
Single electrode potential of
LiCo1/2Ni1/2 V04. w.r.t. Li in 1MliClO4 3.0lv

In propylene carbonate.
A standard procedure in followed to measure the single electrode potential of the cathode.
Oxides of lithium, cobalt, nickel & vanadium were ground well in a pestle / mortar arrangement. After grinding the powder was mixed with glycerol & ground well to obtain a paste. This paste was then heated initially slowly up to 250°C & finally to 750°C for 12 hours. The product obtained was cooled & than ground well & x-rays for confirmation of this product.
Example - 2 Components
Li2O 0.30 gm
Co304 0.80 gm
NiO 0.75 gm
V2O5 1.82gm
Binder (Glycerol) 4 ml
Temperature 200°C - 750°C
Duration of heating 10 hrs
Colour of the product brown
Efficiency of the product 96%
Phase Single
Single electrode potential of
LiCo1/2Ni1/2 V04w.r.t. Li in 1MHC1O4 3.01v
In propylene carbonate.

A standard procedure is followed to measure the single electrode potential of the cathode.
Process is same as described in example 1.
The following advantages are claimed in this invention for the preparation of lithium cobalt nickel vanadate.
An uniform homogeneous mixture of the reacting components viz., oxides of lithium, cobalt, nickel and vanadium were made into a paste to get a product of high purity.
Glycerol was used as a solvent for binding the oxides viz., cobalt, nickel, vanadium and lithium for making a paste of required consistency. The addition of glycerol enhanced the product of fine particles.
The excess addition of glycerol (solvent) as a binding material for the oxides does not change the colour or quality of the end product.
Since pure oxides are used in fine form and homogenously prepared paste was obtained, calcinations of the compound leaves all the reactants to react uniformly to get fine resultant product without leaving any unreacted initial components.

We claim:
1. A novel process for the synthesis of lithium cobalt nickel vanadate (LiCo1/2Ni1/2
V04) as cathode material for high voltage lithium ion cells which comprises by
mixing lithium oxides, cobalt oxide, nickel oxide & vanadium oxide in molar ratios
of 1 : 1/2 : 1/2 : 1 respectively and then preparing a paste by adding binding agent,
heating the above paste upto 750°C for a maximum period of 12 hours and then,
cooling the product to get lithium cobalt nickel vanadate (LiCo1/2Ni1/2V04).
2. A novel processas claimed in 1 claim wherein all reactants react uniformly.
3.. A novel processas claimed in claimsl-2 wherein glycerol in used as binding agent to form a paste with the reactants viz., oxides of cobalt, nickel, vanadium with Li2O.
4. A novel processas claimed in claims 1-3 wherein process produces a single phase
LiCo1/2Ni1/2V04 free from impurity.
5. A novel processas claimed in claims 1-4 wherein heating is effected in between
150-750°C in a furnace makes all the reactants to react uniformly leaving no initial
reactant left un-reacted.
6. A novel process for the synthesis of lithium cobalt nickel vanadate (LiCo1/2Ni1/2
V04) cathode material for high voltage lithium ion cells as herein described with
reference to the examples.

Documents:

356-del-2001-abstract.pdf

356-del-2001-claims.pdf

356-del-2001-correspondence-others.pdf

356-del-2001-correspondence-po.pdf

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

356-del-2001-drawings.pdf

356-del-2001-form-1.pdf

356-del-2001-form-18.pdf

356-del-2001-form-2.pdf

356-del-2001-form-3.pdf

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Patent Number

231609

Indian Patent Application Number

356/DEL/2001

PG Journal Number

13/2009

Publication Date

27-Mar-2009

Grant Date

06-Mar-2009

Date of Filing

27-Mar-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	ARIYANAN MANI	CENTRAL ELECTRO-CHEMICAL RESEARCH INSTITUTE, KARAIKUDI 630 003, TAMILNADU, INDIA.
2	THIAGARAJAN VASUDEVAN	INDUSTRIAL CHEMISTRY, ALAGAPPA UNIVERSITY, KARAIKUDI 630 003, TAMILNADU, INDIA.
3	RAMAIYER GANGADHARAN	INDUSTRIAL CHEMISTRY, ALAGAPPA UNIVERSITY, KARAIKUDI 630 003, TAMILNADU, INDIA.
4	ANGAIAH SUBRAMANIAN	INDUSTRIAL CHEMISTRY, ALAGAPPA UNVERSITY, KARAIKUDI 630 003, TAMILNADU, INDIA.

PCT International Classification Number

H01M 4/02

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA