Title of Invention	"AN IMROVED PROCESS FOR THE PREPARATION OF LITHIUM PER CHLORATE (LICLO4), USEFUL AS ELECTROLYTE FOR NON-AQUEOUS BATTERIES"
Abstract	This invention relates to an improved process for preparation of lithium perchlorate (LIC1O4) useful as electrolyte for non-aqueous batteries. A simple method of preparing this compound viz., LiClO4 is as follows. A required quantity of LiOH, Li2CO3 or Li2O was ground well in aqueous media. In order to avoid explosive hazards a paste was prepared in aqueous solution before neutralizing the compound. This paste was then carefully neutralized by adding calculated quantity of HC1O4 The solution was then slowly evaporated to saturation and was cooled for crystallization to get pure LiClO4 which is free from impurities.

Title of Invention

"AN IMROVED PROCESS FOR THE PREPARATION OF LITHIUM PER CHLORATE (LICLO4), USEFUL AS ELECTROLYTE FOR NON-AQUEOUS BATTERIES"

Abstract

This invention relates to an improved process for preparation of lithium perchlorate (LIC1O4) useful as electrolyte for non-aqueous batteries. A simple method of preparing this compound viz., LiClO4 is as follows. A required quantity of LiOH, Li2CO3 or Li2O was ground well in aqueous media. In order to avoid explosive hazards a paste was prepared in aqueous solution before neutralizing the compound. This paste was then carefully neutralized by adding calculated quantity of HC1O4 The solution was then slowly evaporated to saturation and was cooled for crystallization to get pure LiClO4 which is free from impurities.

Full Text	This invention relates to an improved process for preparation of lithium perchlorate (LIC1O4) useful as electrolyte for non-aqueous batteries. Perchlorates can be prepared for thermal decomposition of chlorate. This method is perhaps the oldest procedure known. However the yield is poor F.Von Stadion, Ann. Phys. (Leipzing 52 (1816) 219. Electrolytic oxidation of chlorate is well known and several authors have achieved good results by different procedures. J.W. Mellor in 'A Comprehensive Treatise of Inogranic and Theoretical Chemistry', Vol II, Longmans, London, (1946) p.374, J.C. Schumacher, Perchlorates their properties Manufacture and uses Reinhold, New York (1960), F.Foerster, Z.Elektrochem, 4 (1898) 386, F.Winteler, Z. Elektrochem, 5(1898) 49, W. Oechsli, Z. Elektrochem, 9(1903) 807, A.J. Allmand, Principles of Applied Electrochemistry, Longmans Green, New York (1912), Ehrhardt, Udo, U.S. Patent 1, 880, 927 (1932), J.G. Williams, Trans, Faraday soc, 15 (1920) 134, E. Balu and R. Weingand, Z. Elektrochem, 27 (1921) 1, P. Lederlin, U.S. Patent 693, 035 (1902), P. Lederlin, U.S. Patent 727, 813 (1903), O. Lederlin, U.S. Paten 723, 753 (1903) to obtain good quality of perchlorate. Direct oxidation of hypochlorite to perchlorate N.V.S. knibbs and H. Palfreeman, Trans Faraday Soc, 16 (1920) 402, K. Sugino, K.Koizumi and K.Kritahara, Japan Patent 129, 657 (1939) was also yield good quality of perchlorate. In the above conventional procedure any one of the following disadvantages are observed. 1. Needs electrolysis and hence time consuming. 2. Needs costly equipments for electrolysis. 3. Limitation in the preparation because only 30 to 40% concentration alone in achieved. 4. Degradation of anodes on long time electrolysis. 5. Expensive 6. Crystallization of the product needs tedious procedures. The main object of this present invention is to formulate a new procedure for the synthesis of or for the preparation of an improved for preparation of lithium perchlorate (LiClO4) useful as electrolyte for non-aqueous batteries which obviates the draw backs of the known methods. Further the object of this invention is to ensure simple procedure for the preparation of lithium perchlorate electrolyte for non-aqueous batteries & polymer electrolyte cells and to achieve 100% efficiency of preparing this compound. The object of this invention is to prepare vary pure LiClO4 by simple procedures. Another object of this invention is to prepare LiClO4 by non electro chemical method. Yet another object this invention is to prepare LiClO4 by least expensive procedures. Still another object of this invention is to prepare LiClO4 by simple chemical method. LiCo3 or LiOH is allowed to react with HC1O4 directly in a predetermined calculated quantity to neutralize the base and then crystallize and get the compound in its purest form. This procedures obviates the defects and drawbacks hither to known In other methods of preparation of this compound from the known procedures available in literature. Accordingly the present invention relates to an improved process for preparation of lithium per chlorate(LiC1O4), useful as electrolyte for non-aqueous batteries which comprises: grinding lithium source in aqueous medium to get a paste, adding HCIO4 to above lithium paste wherein the molar ratio of lithium source and HC104 is 1 : 1 .to neutralize to pH7, at room temperature, concentrating the neutralized solution followed by crystallization to In an embodiment of the invention the lithium source used may be selected from LiOH, LiCO3, Li2O. The temperature used may be room temperature. In an embodiment of this invention LiOH or Li2CO3 or Li2O may be made into a paste. In an embodiment of this invention the ratio of lithium salts viz., LiOH, Li2CO3 or Li2O : HClO4isl : 1. In an embodiment of this invention L1C1O4 solution obtained may be concentrated & then allowed to crystallize. In an embodiment of this invention the crystallization may be effected by heating followed by cooling. In order to obviate the above disadvantages the following new procedure was suggested and developed to yield product of high purity and good yield. A simple method of preparing this compound viz., LiCIO4 is as follows. A required quantity of LiOH, Li2CO3 or Li2O was ground well in aqueous media. In order to avoid explosive hazards a paste was prepared in aqueous solution before neutralizing the compound. This paste was then carefully neutralized by adding calculated quantity of HC104. The solution was then slowly evaporated to saturation and was cooled for crystallization to get pure LiClO4 which is free from impurities. The present invention describes the method of synthesis of LiClC>4 salt, which is useful as a battery electrolyte in non-aqueous solvent for lithium cells. A paste of Li2CO3 or LiOH in aqueous solution is allowed to neutralize with calculated quantity of HC1O4 and the product was crystallized and was examined for its purity and was identified by conductivity measurement and usual chemical analysis. This is a single step process needs no costly equipments or any electrolysis process no side reactions occur. The product obtained is pure because starting chemicals are pure. The following examples are given by the way of illustration and should not be construed the scope of this invention. The following examples give the way of synthesizing LiClO4 Example -1 Components LiOH 1 mole HC1O4 1 mole Yield 99% Temperature -4tolOO°C Nature of the solvent distilled water Colour of the product white Equivalent Conductance of LiClO4 27.34 ohm"Icm2mole"1 In 1 molar PC at 30°C Li2Co3 or LiOH or LiNO3 or Li2O salt was taken a crucible and was groundwell. A small quantity of triple distilled water was added and ground well with a pestle so was to get a paste. This paste was transferred into a beaker and then allowed to react with a 20% pure A.R. solution of perchloric acid kept at -4°C, care was taken with the addition of acid was made in small quantities and it was necessary that the whole reaction was ceased when further addition of a small quantity of HC104 did not produce any change. The solution was slowly evaporated till a concentrated saturated solution was obtained. The vessel was kept for cooling LiC104 crystals are formed. Example -2 Components Li2O 1 mole HC1O4 1 mole Yield 99% Temperature -4 to lOO°C Nature of the solvent distilled water Colour of the product white Equivalent Conductance of LiClO4 27.34 ohm"1cm2mole"1 In 1 molar PC at 30°C The method use d in same as described in example Advantages : 1. The product obtained by this method is less expensive than from the other electrochemical methods. 2. The product obtained is of high purity 3. The efficiency of yield is very high. 4. No expensive equipments are required for the preparation 5. It is a single step process 6. No side reactions occur We Claim: 1. An improved process for preparation of lithium per chlorate(LiC1O4), useful as electrolyte for non-aqueous batteries which comprises: grinding lithium source in aqueous medium to get a paste, adding HCIO4 to above lithium paste wherein the molar ratio of lithium source and HC1O4 is 1:1 .to neutralize to pH7, at room temperature, concentrating the neutralized solution followed by crystallization to get LiClO4. 2. A process as claimed in claim 1 wherein lithium source used is selected from LiOH, Li2CO3, Li2O. 3. An improved process for preparation of lithium per chlorate (LiClO4), useful as electrolyte for non-aqueous batteries substantially as herein described with reference to the examples.

Full Text

This invention relates to an improved process for preparation of lithium perchlorate (LIC1O4) useful as electrolyte for non-aqueous batteries.
Perchlorates can be prepared for thermal decomposition of chlorate. This method is perhaps the oldest procedure known. However the yield is poor F.Von Stadion, Ann. Phys. (Leipzing 52 (1816) 219. Electrolytic oxidation of chlorate is well known and several authors have achieved good results by different procedures. J.W. Mellor in 'A Comprehensive Treatise of Inogranic and Theoretical Chemistry', Vol II, Longmans, London, (1946) p.374, J.C. Schumacher, Perchlorates their properties Manufacture and uses Reinhold, New York (1960), F.Foerster, Z.Elektrochem, 4 (1898) 386, F.Winteler, Z. Elektrochem, 5(1898) 49, W. Oechsli, Z. Elektrochem, 9(1903) 807, A.J. Allmand, Principles of Applied Electrochemistry, Longmans Green, New York (1912), Ehrhardt, Udo, U.S. Patent 1, 880, 927 (1932), J.G. Williams, Trans, Faraday soc, 15 (1920) 134, E. Balu and R. Weingand, Z. Elektrochem, 27 (1921) 1, P. Lederlin, U.S. Patent 693, 035 (1902), P. Lederlin, U.S. Patent 727, 813 (1903), O. Lederlin, U.S. Paten 723, 753 (1903) to obtain good quality of perchlorate. Direct oxidation of hypochlorite to perchlorate N.V.S. knibbs and H. Palfreeman, Trans Faraday Soc, 16 (1920) 402, K. Sugino, K.Koizumi and K.Kritahara, Japan Patent 129, 657 (1939) was also yield good quality of perchlorate.
In the above conventional procedure any one of the following disadvantages are observed.
1. Needs electrolysis and hence time consuming.
2. Needs costly equipments for electrolysis.

3. Limitation in the preparation because only 30 to 40% concentration
alone in achieved.
4. Degradation of anodes on long time electrolysis.
5. Expensive
6. Crystallization of the product needs tedious procedures.
The main object of this present invention is to formulate a new procedure for the synthesis of or for the preparation of an improved for preparation of lithium perchlorate (LiClO4) useful as electrolyte for non-aqueous batteries which obviates the draw backs of the known methods.
Further the object of this invention is to ensure simple procedure for the preparation of lithium perchlorate electrolyte for non-aqueous batteries & polymer electrolyte cells and to achieve 100% efficiency of preparing this compound.
The object of this invention is to prepare vary pure LiClO4 by simple procedures.
Another object of this invention is to prepare LiClO4 by non electro chemical method.
Yet another object this invention is to prepare LiClO4 by least expensive procedures.
Still another object of this invention is to prepare LiClO4 by simple chemical method. LiCo3 or LiOH is allowed to react with HC1O4 directly in a predetermined calculated quantity to neutralize the base and then crystallize and get the compound in its purest form. This procedures obviates the defects and drawbacks hither to known

In other methods of preparation of this compound from the known procedures available in literature.
Accordingly the present invention relates to an improved process for preparation of lithium per chlorate(LiC1O4), useful as electrolyte for non-aqueous batteries which comprises: grinding lithium source in aqueous medium to get a paste, adding HCIO4 to above lithium paste wherein the molar ratio of lithium source and HC104 is 1 : 1 .to neutralize to pH7, at room temperature, concentrating the neutralized solution followed by crystallization to
In an embodiment of the invention the lithium source used may be selected from LiOH, LiCO3, Li2O.
The temperature used may be room temperature.
In an embodiment of this invention LiOH or Li2CO3 or Li2O may be made into a paste.
In an embodiment of this invention the ratio of lithium salts viz., LiOH, Li2CO3 or Li2O : HClO4isl : 1.
In an embodiment of this invention L1C1O4 solution obtained may be concentrated & then
allowed to crystallize.
In an embodiment of this invention the crystallization may be effected by heating
followed by cooling.
In order to obviate the above disadvantages the following new procedure was suggested
and developed to yield product of high purity and good yield.
A simple method of preparing this compound viz., LiCIO4 is as follows. A required quantity of LiOH, Li2CO3 or Li2O was ground well in aqueous media. In order to avoid explosive hazards a paste was prepared in aqueous solution before neutralizing the compound. This paste was then carefully neutralized by adding

calculated quantity of HC104. The solution was then slowly evaporated to saturation and was cooled for crystallization to get pure LiClO4 which is free from impurities. The present invention describes the method of synthesis of LiClC>4 salt, which is useful as a battery electrolyte in non-aqueous solvent for lithium cells. A paste of Li2CO3 or LiOH in aqueous solution is allowed to neutralize with calculated quantity of HC1O4 and the product was crystallized and was examined for its purity and was identified by conductivity measurement and usual chemical analysis.
This is a single step process needs no costly equipments or any electrolysis process no side reactions occur. The product obtained is pure because starting
chemicals are pure.
The following examples are given by the way of illustration and should
not be construed the scope of this invention.
The following examples give the way of synthesizing LiClO4
Example -1
Components
LiOH 1 mole
HC1O4 1 mole
Yield 99%
Temperature -4tolOO°C
Nature of the solvent distilled water
Colour of the product white
Equivalent Conductance of LiClO4 27.34 ohm"Icm2mole"1

In 1 molar PC at 30°C
Li2Co3 or LiOH or LiNO3 or Li2O salt was taken a crucible and was groundwell. A small quantity of triple distilled water was added and ground well with a pestle so was to get a paste. This paste was transferred into a beaker and then allowed to react with a 20% pure A.R. solution of perchloric acid kept at -4°C, care was taken with the addition of acid was made in small quantities and it was necessary that the whole reaction was ceased when further addition of a small quantity of HC104 did not produce any change. The solution was slowly evaporated till a concentrated saturated solution was obtained. The vessel was kept for cooling LiC104 crystals are formed.
Example -2
Components
Li2O 1 mole
HC1O4 1 mole
Yield 99%
Temperature -4 to lOO°C
Nature of the solvent distilled water
Colour of the product white
Equivalent Conductance of LiClO4 27.34 ohm"1cm2mole"1
In 1 molar PC at 30°C

The method use d in same as described in example
Advantages :
1. The product obtained by this method is less expensive than from the other
electrochemical methods.
2. The product obtained is of high purity
3. The efficiency of yield is very high.
4. No expensive equipments are required for the preparation
5. It is a single step process
6. No side reactions occur

We Claim:
1. An improved process for preparation of lithium per chlorate(LiC1O4), useful as
electrolyte for non-aqueous batteries which comprises: grinding lithium source in
aqueous medium to get a paste, adding HCIO4 to above lithium paste wherein the
molar ratio of lithium source and HC1O4 is 1:1 .to neutralize to pH7, at room
temperature, concentrating the neutralized solution followed by crystallization to
get LiClO4.
2. A process as claimed in claim 1 wherein lithium source used is selected from
LiOH, Li2CO3, Li2O.
3. An improved process for preparation of lithium per chlorate (LiClO4), useful as
electrolyte for non-aqueous batteries substantially as herein described with
reference to the examples.

Documents:

525-del-2001-abstract.pdf

525-del-2001-claims.pdf

525-del-2001-correspondence-others.pdf

525-del-2001-correspondence-po.pdf

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

525-del-2001-form-1.pdf

525-del-2001-form-18.pdf

525-del-2001-form-2.pdf

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Patent Number

233389

Indian Patent Application Number

525/DEL/2001

PG Journal Number

13/2009

Publication Date

27-Mar-2009

Grant Date

29-Mar-2009

Date of Filing

26-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	EXTENDED SRF, DEPT. OF INDUSTRIAL CHEMISTRY, ALAGAPPA UNIVERSITY, KARAIKUDI 630003
2	THIAGARAJAN VASUDEVAN	PROF AND HEAD, ALAGAPPA UNIVERSITY, KARAIKUDI 630003
3	RAMA IYER GANGADHARAN	EMERITUS SCIENTIST, ALAGAPPA UNIVERSITY, KARAIKUDI 630003

PCT International Classification Number

H01M 004/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA