Within Group 10, nickel has a slightly limited range of stable
oxidation states, especially when compared to its heavier congeners
in palladium and platinum. The +2 valence state dominates the
coordination chemistry of nickel, and even though the higher oxidation
states are possible, they are much more prevalent for palladium
and platinum. Having said that, Ni(III) has made a very
notable appearance in practical chemistry, in the form of its use
in nickel/cadmium battery.