> From what I read there, apparently, ingesting an electricly charged
> silver particle is much safer than ingesting a silver ion.

An ion means charged particle.
The simplest ion would be an electron(-) or proton (H+)
Ag+ is a positively charged ion.

electrically charged silver particle and ion are the same thing..
the charged particle, ion could be an electron/proton, atom, 
molecule, or "cluster of molecules"

I'm not clear about all the particle size stuff myself.

from my understanding of things
like charges repel.
Ag+ ions will remain separate unless they cluster as a result of 
other microelectrical forces.