Lecture Notes in Energy 56 Mark Prelas Matthew Boraas Fernando De La Torre Aguilar John-David Seelig Modeste Tchakoua Tchouaso Denis Wisniewski Nuclear Batteries and Radioisotopes Lecture Notes in Energy Volume 56 LectureNotesinEnergy(LNE)isaseriesthatreportsonnewdevelopmentsinthe studyofenergy:fromscienceandengineeringtotheanalysisofenergypolicy.The series’ scope includes but is not limited to, renewable and green energy, nuclear, fossil fuels and carbon capture, energy systems, energy storage and harvesting, batteries and fuel cells, power systems, energy efficiency, energy in buildings, energy policy, as well as energy-related topics in economics, management and transportation.BookspublishedinLNEareoriginalandtimelyandbridgebetween advanced textbooks and the forefront of research. Readers of LNE include postgraduate students and non-specialist researchers wishing to gain an accessible introduction to a field of research as well as professionals and researchers with a needforanup-to-datereferencebookonawell-definedtopic.Theseriespublishes single- and multi-authored volumes as well as advanced textbooks. More information about this series at http://www.springer.com/series/8874 Mark Prelas Matthew Boraas (cid:129) Fernando De La Torre Aguilar John-David Seelig Modeste Tchakoua Tchouaso (cid:129) Denis Wisniewski Nuclear Batteries and Radioisotopes 123 Mark Prelas John-David Seelig Nuclear ScienceandEngineering Institute Nuclear ScienceandEngineering Institute University of Missouri University of Missouri Columbia, MO Columbia, MO USA USA MatthewBoraas Modeste TchakouaTchouaso Nuclear ScienceandEngineering Institute Nuclear ScienceandEngineering Institute University of Missouri University of Missouri Columbia, MO Columbia, MO USA USA Fernando DeLa TorreAguilar DenisWisniewski Nuclear ScienceandEngineering Institute Nuclear ScienceandEngineering Institute University of Missouri University of Missouri Columbia, MO Columbia, MO USA USA ISSN 2195-1284 ISSN 2195-1292 (electronic) Lecture Notesin Energy ISBN978-3-319-41723-3 ISBN978-3-319-41724-0 (eBook) DOI 10.1007/978-3-319-41724-0 LibraryofCongressControlNumber:2016945768 ©SpringerInternationalPublishingSwitzerland2016 Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpart of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilarmethodologynowknownorhereafterdeveloped. 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Printedonacid-freepaper ThisSpringerimprintispublishedbySpringerNature TheregisteredcompanyisSpringerInternationalPublishingAGSwitzerland As a gesture to the fading concepts of academic integrity and excellence, the authors wish to dedicate this book to the students, alums, staff, and faculty of the Nuclear Science and Engineering Institute (NSEI) at the University of Missouri. Its history began in 1957 when the university offered its first course in nuclear engineering through the chemical engineering department. The university began hiring dedicated nuclear engineering faculty who then designed and built the University of Missouri Research Reactor. Unlike other programs of the era where the reactor remained in the nuclear engineering department, the research reactor management structure was moved to the University of Missouri System where it was a shared resource for the system’s four campuses. In 1964 NSEI’s first Masters of Science student graduated and the university formally established a degree program in nuclear engineering. It offered MS and PhDs in Nuclear Engineering with a traditional emphasis and a health physics emphasis. In 1980, it developed one of the first and most prestigious nationallyaccredited programs in medical physics through its offering of MS and PhD degrees with medical physics emphasis. NSEI’s approximately 600 alumni have served in government, the military, industry,hospitals,thehealthprofessionsand academia in the US and internationally with great honor. Many NSEI alumni have walked the halls of power serving as corporate leaders, entrepreneurs, a Chairman of the Nuclear Regulatory Commission, an Assistant Secretary of Defense, Generals, academic program chairs, deans, respected faculty, medial physicists at prestigious hospitals such as MD Anderson, Washington University, and many more of the greatest hospitals in the US. A significant fraction of the PhDs awarded in the nuclear engineering community nationally graduated from NSEI and its predecessor (the nuclear engineering program at MU). This book has five authors from the last group of NSEI graduate students. Remember: NSEI, 1958–2012 Preface Nuclear Batteries and Radioisotopes and its sister book, Nuclear-Pumped Lasers (published by Springer in 2016), examine the direct conversion of nuclear energy into other useful energy forms. What these twobooksdemonstrate isthat all types of nuclear energy conversion have common features. These include the principles of the interaction of ionizing radiation with matter (covered as a chapter in Nuclear-Pumped Lasers), the matching up of the range of the ionizing radiation withthescalelengthofthetransducer,theconceptofreactionrates,theconceptof power density, as well as many other shared principles. Another shared common- alitybetweenthetwotextsisthatbothwereoriginatedfromgraduatelevelcourses. Nuclear Batteries and Radioisotopes was developed from a graduate level course of the same title taught by Prof. Prelas during the fall semester 2015. Five of the students who participated in this course assisted in the writing of this text as authors. Nuclear Batteries and Radioisotopes was undertaken to provide researchers and students in the field a resource which can be used as a tool to identify the critical engineering issues in nuclear battery design. This book expands upon the funda- mental aspects of radiation transport and the physics of transducers. Ionizing radiation transports through matter with a characteristic scale length Called the range.Transducersalsohavebasicscalelengthsoverwhichtheyabsorbpowerand convert that power into another useful form. The matchup between the transducer scalelengthandtherangeoftheionizingradiationisoneofthedominantfactorsin determiningthesystemefficiencyofthenuclearbatterydesign.Thecomplexitiesof nuclearbatterydesignaredifficulttocomprehendevenforskilledpractitioners.The field seems to gain a new life and renewed interest every 20 years or so which so happens to coincide with generational changes in the scientific community. The driving force of thiscycle ofrenewed interest isthe enormity of amount ofenergy that is stored in radioisotopes. Often times the lessons learned from the previous cycles are lost in the enthusiasm of the current cycle. More so, it is the complex nature of the designs that make the lessons from previous works hard to interpret. vii viii Preface The goal of this book is to help simplify the factors which make the design of nuclear batteries so complex. In Chap. 1, the physical parameters of the radioiso- topesourcesthemselvesareexplored.Compoundscanbeformedwhichcontainthe radioisotope atoms. Chemically, there isa compound which maximizes the atomic number density of the radioisotope. This compound then has the highest possible concentrationoftheradioisotopeandthushasthemaximumthermalpowerdensity thatisfeasibleforthatradioisotope.Bytakingtheinverseofthemaximumthermal power density, the minimum volume of the compound able to produce 1 W of powercanbefound.Thisminimumvolumeprovidesthereaderafeelforthescale of a device fueled by a specific radioisotope. Chapter2looksattheradioisotopesandwheretheycomefromorhowtheycan be made. There are two fundamental sources of radioisotopes: naturally occurring; andman-made.Inchoosingaradioisotopeforanuclearbatterydesign,thedesigner will havequestions.Aretheisotopes readilyavailable?Howmuch dotheisotopes cost? These two fundamental questions are addressed. Chapter 3 focuses on the ranges of ionizing radiation in matter as well as the scalelengthofthetransducersofinterest.Thescalelengthmatchupoftheionizing radiationrangetothescaleofthetransducerisanimportantissue.Ifthematchupis poor, the efficiency of the nuclear battery will be low. The power deposition effi- ciency in the transducer is dependent upon the scale length matchup between the charged particles ranges and the transducer. Chapter 4 covers the atomic dilution factor, which is the ratio of the number of radioisotope atoms in the volume of the nuclear battery versus the number of radioisotope atoms in the same volume of the compound which maximizes the atomicdensityofradioisotope.Thewaythesourceisinterfacedwiththetransducer in the nuclear battery design will determine how large the dilution factor will be. A surface source interface will have large dilution factors relative to volume interfaces.However,evenvolumeinterfaceswillhavesomelevelofdilutionfactor. Thedilutionfactorisameasureofhowmuchthepowerdensityinanuclearbattery will be diminished from the optimum possible value. Transducer and system efficiency of the nuclear battery is covered in Chap. 5. Specific examples of transducers are discussed and the reader is given a method- ology of making such determinations for new transducer concepts beyond those that are already known. In addition the effects of radiation damage on components of a nuclear battery are examined. The goal of this chapter is to consider the integrated nuclear battery system. A section on problems and issues in nuclear battery literature is included. The purpose of this section is to provide the reader with ability to evaluate reported systems in the literature and to develop the nec- essaryskillstousethetoolsdevelopedinpriorchapterstoaccuratelydeterminethe validity of claims that are made. In Chap. 6, a host of projected applications are discussed and the capability of nuclear battery systems is examined to determine the viability of batteries to meet the challenges presented by the specific applications. A brief discussion of the transition from radioisotopes to fission reactors is discussed which examines the benefits of the control of the power density which fission reactors offer. Preface ix Appendix A has valuable data on the range of ionizing radiation from viable radioisotopesthatmaybeusedforapplicationsinnuclearbatteries.Therangedata helps the reader understand the scale length of the ionizing radiation ranges. Appendix B has formulas which represent the energy spectra of beta particles emitted from key radioisotopes. AppendixClooksatadvancedtheoreticalconceptsforthepurposeofpresenting methodologies for the reader to be able to use the tools presented in the book to tackle never-seen-before designs and to understand the potential of the design. The concepts from the chapters of this text demonstrate the sophistication and subtleties of nuclear battery design. There are numerous difficulties involved in integrating these concepts into a nuclear battery system and at least in part is a reason why this technology seems to be enthusiastically rediscovered every gen- eration with high expectations solely based on the energy storage potential of radioisotopes.Itisthehumblehopeoftheauthorsthatthistextwillhelpthereader tofocusonthefundamentalengineeringlimitations whichunderlienuclearbattery design and will temper expectations of the technology. It is only through a full understanding of limitations that real breakthroughs can be made. Columbia, USA Mark Prelas Matthew Boraas Fernando De La Torre Aguilar John-David Seelig Modeste Tchakoua Tchouaso Denis Wisniewski