It can indeed be recycled after it degrades into copper, but it will take far longer that you claim for it to do so.
The half life of nickel-63 is 101.2 years which means that after 101.2 years approximately half of the core will have degraded to copper, then after 101.2 more years approximately half of the remaining will have degraded, leaving approximately a quarter, then after 101.2 more years there’ll be approximately one eighth, and so on. This is how radioactive decay works.
The battery, they claim, functions for 50 years or so, which is probably because after 50 years the radioactive decay has slowed by over 25% (can’t be bothered to work out the actual amount but its at least this much). This 50 years doesn’t mean that all the radioactive material has decayed, just that a portion of it significant enough to render the battery dead/less effective/etc.
It can indeed be recycled after it degrades into copper, but it will take far longer that you claim for it to do so.
The half life of nickel-63 is 101.2 years which means that after 101.2 years approximately half of the core will have degraded to copper, then after 101.2 more years approximately half of the remaining will have degraded, leaving approximately a quarter, then after 101.2 more years there’ll be approximately one eighth, and so on. This is how radioactive decay works.
The battery, they claim, functions for 50 years or so, which is probably because after 50 years the radioactive decay has slowed by over 25% (can’t be bothered to work out the actual amount but its at least this much). This 50 years doesn’t mean that all the radioactive material has decayed, just that a portion of it significant enough to render the battery dead/less effective/etc.