[gus_massa]

It's not a chemical battery. The energy comes from the nuclear desintegration of radioactive nickel. So the charge is inmmune to most of the usual problems.

On the other hand, I don't know how strong are the layers that aborb the radiation and cretes the electricity.

[kedikedi]

Ah, you’re right! I was talking about the “comparable” batteries, assuming them being chemical batteries