A 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 the negative electrode of a battery, whereby the composite powder comprises composite particles, whereby the composite particles comprise a matrix material and silicon, whereby the composite particles have a particle size distribution having a d10 and a d90, whereby over at least part of the size range from d10 to d90 the composite particles have a size-dependent silicon content. Preferably a finer fraction of the composite powder has an average particle size D1 and a silicon content S1 and a coarser fraction of the composite powder has an average particle size D2 and a silicon content S2, whereby a size dependence factor F is defined as follows F=(S2−S1)/(D2−D1), whereby the absolute value of the size dependence factor F is at least 0.04 wt % silicon/μm.