Liquid Polymer Isotope Batteries

A recent development which could dramatically improve the efficiency of betavoltaic batteries has been spear-headed by team working at Rice University in Houston, Texas, who have painted a thin layer of a liquid polymer containing an isotope variant of hydrogen called tritium onto the surface of a porous semiconductor, creating a very thin layer of radioactive material that soaks into the pores.
The process reduces the distance that the electrons have to travel, from the decaying nuclei contained by the tritium, to the semiconductor where they are turned into current.
The use of thin layers means that the batteries can be made into a wide range of shapes, such as thin sheets.