Really poorly reported. The patent implies that it's just nickel and
hydrogen, under pressure and heat. However, it also specifies Nickel
62, which is under 3% natural abundance. But that's for reasons of
avoiding radiation. The paper says "The system on which we operate
consists of Ni, in H atmosphere and in the presence of additives
placed in a sealed container and heated by a current passing through
a resistor."
Additives? What additives? It's tempting to say "magic pixie dust."
But I don't believe that they are necessarily making this up, I'm
just noticing that, like a long line before them, they aren't
disclosing what are quite likely critical details. It's not like
nobody tried pressurizing and heating nickel and hydrogen before!
I'll get excited when someone completely independent replicates this.
Until then, well, we've been burned too many times. Or not-burned, as
the case was. Not even hot enough to burn.