Positive electrode material for lithium-ion battery
A compound of formula Li 4+x MnM 1 a M 2 b O c wherein: M 1 is selected from the group consisting in Ni, Mn, Co, Fe and a mixture thereof; M 2 is selected from the group consisting in Si, Ti, Mo, B, Al and a mixture thereof; with: −1.2≦x≦3; 0<a≦2.5; 0≦b≦1.5; 4.3≦c≦10; and c=4+a+n·b+x/2 wherein n=2 when M 2 is selected from the group consisting in Si, Ti, Mo or a mixture thereof; and n=1.5 when M 2 is selected from the group consisting in B, Al or a mixture thereof; and n=0 if b=0.
1. A compound of formula Li 4+x MnM 1 a M 2 b O c
wherein:
M 1 is selected from the group consisting in Ni, Mn, Co, Fe and a mixture thereof;
M 2 is selected from the group consisting in Si, Ti, Mo, B, Al and a mixture thereof;
with:
−1.2≦x≦3;
0<a≦2.5;
0<b≦1.5;
4.3≦c≦10; and
c=4+a+(n·b)+x/2
wherein:
n=2 when M 2 is selected from the group consisting in Si, Ti, Mo or a mixture thereof; and
n=1.5 when M 2 is selected from the group consisting in B, Al or a mixture thereof.
2. The compound according to claim 1 , wherein 0<x≦2.
3. The compound according to claim 1 , wherein 0.5≦a≦1.
4. The compound according to claim 1 , wherein 0<b≦0.5.
5. The compound according to claim 1 , wherein 5≦c≦7.
6. The compound according to claim 1 not containing any molybdenum.
7. A composite material comprising the compound according to claim 1 and carbon in a mass percentage of less than 20% by weight based on the weight of the composite material.
8. A battery of the lithium-ion type comprising a positive electrode comprising the composite material according to claim 7 .
9. A battery of the lithium-ion type comprising a positive electrode comprising the compound according to claim 1 .