Composite powder for use in the negative electrode of a battery and a battery comprising such a composite powder
A composite powder for use in a negative electrode of a battery comprising composite particles, said composite particles comprising a carbon matrix material and silicon-based particles embedded in said carbon matrix material, said composite powder having a Raman spectrum, wherein a D band and a D'band, both corresponding to the carbon matrix material contribution, have their respective maximum intensity I D between 1330 cm −1 and 1360 cm −1 and I D ′ between 1600 cm −1 and 1620 cm −1 , wherein the ratio I D /I D ′ is at least equal to 0.9 and at most equal to 4.0.
1 . A composite powder for use in a negative electrode of a battery comprising composite particles, said composite particles comprising a carbon matrix material and silicon-based particles embedded in said carbon matrix material, said composite powder having a Raman spectrum, wherein a D band and a D′ band, both corresponding to the carbon matrix material contribution, have their respective maximum intensity Ip between 1330 cm −1 and 1360 cm −1 and I D ′ between 1600 cm −1 and 1620 cm −1 , wherein the ratio I D /I D ′ is at least equal to 0.9 and at most equal to 3.8.
2 . The composite powder according to claim 1 , wherein the I D /I D ′ ratio is at least equal to 1.0 and at most equal to 3.0.
3 . The composite powder according to claim 1 , wherein the I D /I D ′ ratio is at least equal to 1.0 and at most equal to 2.6.
4 . The composite powder according to claim 1 , wherein the carbon matrix material is soft carbon.
5 . The composite powder according to claim 1 , wherein the composite powder has a silicon content S expressed in weight percent (wt %), wherein 10 wt %≤S≤60 wt %.
6 . The composite powder according to claim 1 , wherein the composite powder has a carbon content C expressed in weight percent (wt %), wherein 30 wt %≤C≤90 wt %.
7 . The composite powder according to claim 1 , wherein the composite powder has a silicon content S and an oxygen content N, both expressed in weight percent (wt %), wherein N≤0.20 S.
8 . The composite powder according to claim 1 , wherein the silicon-based particles are characterized by a number-based size distribution having a d50, the d50 being larger than or equal to 20 nm and smaller than or equal to 150 nm.
9 . The composite powder according to claim 1 , wherein the silicon-based particles are covered, for at least 50% of their surface, with the carbon matrix material.
10 . The composite powder according to claim 1 , wherein a silicon content in the silicon-based particles is at least equal to 80 wt %.
11 . The composite powder according to claim 1 , wherein the composite powder also comprises graphite and/or graphene particles, such that less than 10% of the surface of the graphite and/or graphene particles is covered with the carbon matrix material.
12 . The composite powder according to claim 1 , wherein the composite powder has a BET surface area which is at most 10 m 2 /g.
13 . The composite powder according to claim 1 , wherein the composite particles have a volume-based particle size distribution having a D10, a D50 and a D90, with 1 μm≤D10≤10 μm, 5 μm≤D50≤25 μm and 10 μm≤D90≤40 μm.
14 . A negative electrode comprising a composite powder according to claim 1 .
15 . A battery comprising a negative electrode according to claim 14 .
16 . The composite powder according to claim 1 , wherein the ratio I D /I D ′ is at least equal to 0.9 and at most equal to 3.6.
17 . The composite powder according to claim 1 , wherein the ratio I D /I D ′ is at least equal to 0.9 and at most equal to 3.4.