That thing used the heat. A Beta battery just has new electrons appear, "magically".

https://en.wikipedia.org/wiki/Betavoltaic_device

Thanks for the article. But then it points to the Betacel, USA 1970s (60 pacemakers implanted by 1973).

https://en.m.wikipedia.org/wiki/Betacel

I’m not trying to dismiss a wonderful invention, I just want journalistic integrity. It’s not a first if someone already made a product in 1973.