Blanket for batteries

Engineering physics researchers at the

are devising a unique "blanket" that will enable them to squeeze as much electricity as possible from nuclear-powered batteries the size of a grain of coarse salt.

Such batteries, which exploit the natural decay of radioisotopes to generate electricity, could provide virtually indefinite power for micro-technologies like small robots for military applications or sensors that monitor a building's health.

Other technologies such as fuel cells, chemical batteries or turbine generators also might work in micro-scale applications, said Professor James Blanchard. ‘But all of them are short-lived,’ he said. ‘They either need to be recharged or refuelled. Our niche is things that need to be placed and ignored, and just keep running for years.’

Nuclear microbatteries convert heat or energy to electricity more efficiently when they are hot, so it makes sense to insulate them, said Blanchard. ‘The better the insulation, the hotter the source gets, so the more efficient the battery can be,’ he said.