Prototype nuclear battery packs 10 times more power

Short form: beta decay of nickel-63 has been utilized in prototype nuclear batteries that produce about 10 times the total energy (not power) as a conventional battery… about 3,300 milliwatt-hours (11,880 Joules) of energy per gram. A battery like this would produce a trickle of energy for a century or more and could be useful for things like pacemakers and spacecraft sensors. Not terribly useful for things like cars… the actual power extractable from the battery might not be that great, and it would not be rechargeable (after a number of decades,when it starts to run down due to the halflife consuming a meaningful fraction of the material, it would have to be torn apart and recycled like radioactive electronics).

11,880 Joules in a single gram is pretty good. But over a century you could only extract about half that energy (the halflife of nickel-63 is 101 years, going to stable copper-63), and 11,880 J/2 over 100 years averages a whopping 1.883E-6 watts per gram. One hundred kilos of the stuff would give you 0.2 watts. So… yay, I guess?