Li4Ti5O12, Li(4-a)ZaTi5O12 OR Li4ZßTi(5-ß)O12, PARTICLES, PROCESSES FOR OBTAINING SAME AND USE AS ELECTROCHEMICAL GENERATORS

Abstract

Synthesis process for new particles of Li 4 Ti 5 O 12 , Li (4-α) Z α Ti 5 O 12 or Li 4 Z β Ti (5-β) O 12 , preferably having a spinel structure, wherein β is greater than 0 and less than or equal to 0.5 (preferably having a spinel structure), α representing a number greater than zero and less than or equal to 0.33, Z representing a source of at least one metal, preferably chosen from the group made up of Mg, Nb, Al, Zr, Ni, Co. These particles coated with a layer of carbon notably exhibit electrochemical properties that are particularly interesting as components of anodes and/or cathodes in electrochemical generators.

1 - 4 . (canceled) 
     
     
         5 . Particles of an oxide corresponding to at least one formula selected from:
 Li (4-α) Z α Ti 5 O 12 , wherein α is greater than zero and less than or equal to 0.33; and   Li 4 Z β Ti (5-β) O 12 , wherein β is greater than 0 and less than or equal to 0.5;   wherein Z is at least one metal; and   wherein said particles are obtained by a process for synthesizing said particles in the presence of oxygen,   said process comprising the steps of:   a) preparing an intimately dispersed ternary mixture of TiO x —Li z Y-carbon, wherein   x is a number between 1 and 2,   z is 1 or 2,   Y is a radical chosen from the group consisting of CO 3 , OH, O and TiO 3  or a mixture thereof, and   the carbon is a carbon powder selected from the group consisting of natural or artificial graphite, carbon black, Shawinigan black, Ketjen black and cokes;   b) heating the dispersion at a temperature of between 400 and 1,000° C.;   c) if appropriate, adding a source of at least one metal Z to the ternary mixture,   wherein operating conditions are chosen in such a way as to yield a conversion of initial products respectively into Li (4-α) Z α Ti 5 O 12  and/or Li 4 Z β Ti (5-β) O 12 .   
     
     
         6 . The particles according to  claim 5 , wherein Z is at least one metal selected from the group consisting of Mg, Nb, Al, Zr, Ni and Co; and 
     
     
         7 . A cathode of an electrochemical generator comprising particles according to  claim 5 . 
     
     
         8 . An anode for an electrochemical generator comprising particles according to  claim 5 . 
     
     
         9 . The particles according to  claim 5 , wherein a core of the particles mainly comprises at least 65% of Li(4−α)ZαTi 5 O 12  or Li4ZβTi(5−β)O12 or a mixture thereof. 
     
     
         10 . The particles of an oxide of  claim 5 , wherein at least one of the particles comprises a spinel crystal structure. 
     
     
         11 . The particles of an oxide according to  claim 5 , wherein the particles have carbon coating with a thickness in a range of 10-450 nm. 
     
     
         12 . The particles of an oxide according to  claim 5 , wherein the particles have a formula of Li (4-α) Z α Ti 5 O 12 , wherein α is greater than zero and less than or equal to 0.33. 
     
     
         13 . The particles of an oxide according to  claim 5 , wherein the particles have a formula of Li 4 Z β Ti (5-β) O 12 , wherein β is greater than 0 and less than or equal to 0.5. 
     
     
         14 . An electrochemical generator of the lithium type comprising an anode of the metallic lithium type and a cathode according to  claim 7 . 
     
     
         15 . The electrochemical generator according to  claim 14 , wherein said cathode is of the Li (4-α) Z α Ti 5 O 12  type and/or of the Li 4 Z β Ti (5-β) O 12  type. 
     
     
         16 . The electrochemical generator according to  claim 14 , wherein said cathode is of the Li (4-α) Z α Ti 5 O 12  type. 
     
     
         17 . The electrochemical generator according to  claim 14 , wherein said cathode is of the Li 4 Z β Ti (5-β) O 12  type.