Lithium is the lightest of the alkali metals, each of these only having one electron in their outer shell. When they lose it in reaction they form a similarly charged monopositve ion. read more
So lithium is generally found to be in +1 oxidation state/charge. But lithium can posses any charge, even +3 also (that would only contain the atom without electron, nucleus). But generally we write charge of lithium as +1 untill and unless conditions are given. read more
Lithium has a charge of Li^+1, phosphite has a charge of PO3^-3. But overall, Li3PO3 would be neutral. read more