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Evaluation of a Silicon 90Sr Betavoltaic Power Source.

ABSTRACT: Betavoltaic energy converters (i.e., ?-batteries) are attractive power sources because of their potential for high energy densities (>200?MWh/kg) and long duration continuous discharge (>1 year). However, conversion efficiencies have been historically low (<3%). High efficiency devices can be achieved by matching ?-radiation transport length scales with the device physics length scales. In this work, the efficiency of c-Si devices using high-energy (>1?MeV) electrons emitted from 90Sr as a power source is investigated. We propose a design for a >10% efficient betavoltaic device, which generates 1?W of power. A Varian Clinac iX is used to simulate the high-energy electrons emitted from 90Sr, and a high efficiency c-Si photovoltaic cell is used as the converter. The measured conversion efficiency is 16%. This relatively high value is attributed to proper length scale matching and the generation of secondary electrons in c-Si by the primary ?-particles.

SUBMITTER: Dixon J

PROVIDER: S-EPMC5131278 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Evaluation of a Silicon 90Sr Betavoltaic Power Source.

Dixon Jefferson J Rajan Aravindh A Bohlemann Steven S Coso Dusan D Upadhyaya Ajay D AD Rohatgi Ajeet A Chu Steven S Majumdar Arun A Yee Shannon S

Scientific reports 20161201

Betavoltaic energy converters (i.e., β-batteries) are attractive power sources because of their potential for high energy densities (>200 MWh/kg) and long duration continuous discharge (>1 year). However, conversion efficiencies have been historically low (<3%). High efficiency devices can be achieved by matching β-radiation transport length scales with the device physics length scales. In this work, the efficiency of c-Si devices using high-energy (>1 MeV) electrons emitted from 90Sr ...[more]

PMID: 27905521

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