Until the inventor Andrea Rossi  discovered the Rossi Effect there were basically only two categories of LENR studied:

  1. Palladium – Deuterium
    (the original Cold Fusion process)
  2. Nickel – Hydrogen

The Rossi Effect is a completely new discovery in the field of LENR technology and raises the available power density of LENR processes several orders of magnitude to at least 10 kW/kg. With Power Densities this high most conventional Energy Applications have the potential of being replaced with an ECAT energy source.

Read more under  The Rossi Effect.