Optimised Positive Electrode Material for Lithium Cell Batteries, Method for the Production Thereof, Electrode, and Battery for Implementing Said Method

Abstract

A material or compound is provided having a spinel structure and corresponding to the formula Li y Ni 0.5 Mn 1.5-x IV Mn x III A z O 4-d , where: 0.02≦x≦0.35; d>0; A is selected from the group comprising Na, K, Mg, Nb, Al, Ni, Co, Zr, Cr, Fe, Cu, Ti, Zn, Si and Mo; 0.8≦y≦1.2; 0≦z≦0.1; and has a mesh parameter of between 8.174 and 8.179 Å.

1 . Compound having a spinel structure, wherein:
 the compound has the formula Li y Ni 0.5 Mn 1.5-x   IV Mn x   III A z O 4-d , with:
 0.02≦x≦0.35; 
 d>0; 
 A selected from the group comprising Na, K, Mg, Nb, Al, Ni, Co, Zr, Cr, Fe, Cu, Ti, Zn, Si and Mo; 
 0.8≦y≦1.2; 
 0≦z≦0.1; 
   and has a mesh parameter of between 8.174 and 8.179 Å.   
   
   
       2 . Compound according to  claim 1 , having a formula Li y Ni 0.5 Mn 1.5-x   IV Mn x   III O 4-d . 
   
   
       3 . Compound according to  claim 2 , having a formula LiNi 0.5 Mn 1.3   IV Mn 0.2   III O 3.9 . 
   
   
       4 . Compound according to  claim 1 , wherein z is higher than 0. 
   
   
       5 . Compound according to  claim 1  having a mesh parameter of between 8.176 and 8.177 Å. 
   
   
       6 . Compound according to  claim 1  having a particle size above 1 μm. 
   
   
       7 . Compound according to  claim 6  having a particle size of between 5 and 10 μm. 
   
   
       8 . Compound according to  claim 1  having a specific surface area of between 1 and 2 m 2 /g. 
   
   
       9 . Method for preparing a compound according to  claim 1 , comprising the following steps:
 forming a mixture by mixing of lithium, nickel and manganese based precursor in stoichiometric conditions with a lithium excess of 1 to 5 mol %;   subjecting the mixture to a first heat treatment at a first temperature of between 550 and 600° C.;   after the first heat treatment, subjecting the mixture to a second heat treatment at a second temperature above 700° C. combined with a cooling in oxygen containing medium.   
   
   
       10 . Electrode comprising a compound according to  claim 1 , as an electrochemically active material. 
   
   
       11 . Electrode according to  claim 10 , wherein the compound is in the form of a dispersion mixed with a conducting additive and/or an organic binder. 
   
   
       12 . Cell battery comprising at least one first electrode according to  claim 10 , and a second electrode made from a material suitable for receiving lithium ions, first electrode and the second electrode being separated by a separator soaked with electrolyte. 
   
   
       13 . Battery comprising at least one cell battery according to  claim 12 . 
   
   
       14 . Method according to  claim 9 , wherein the second temperature is above 800° C.