1. The National Ignition Facility [1] recently reported record amounts of energy produced by laser-based fusion, but it is more of a research facility than a power plant.
2. Do the betavoltaics [2] in some early pacemakers and the small reactor on spacecraft and the Mars Science Laboratory count as radioactive batteries? But I am assuming that, since betavoltaic pacemakers and nuclear spacecraft have been around since Asimov's time, they probably don't count.
The wikipedia page doesn't seem to have any information about "record amounts of energy produced" at NIF. The closest thing I've found is a press release[1] that mentions "highest [neutron] yield achieved so far from a layered DT implosion". Neutron production should be proportional to the number of fusion events (and thus also the energy released). But, its odd that they don't claim this specifically.
2. Do the betavoltaics [2] in some early pacemakers and the small reactor on spacecraft and the Mars Science Laboratory count as radioactive batteries? But I am assuming that, since betavoltaic pacemakers and nuclear spacecraft have been around since Asimov's time, they probably don't count.
[1] http://en.wikipedia.org/wiki/National_Ignition_Facility [2] http://en.wikipedia.org/wiki/Betavoltaics