本論文主要以多尺度模擬方法，結合計算量子力學及分子動力學所計算之熔融鹽材料性質與離子傳輸現象，運用計算流體力學方法執行熱電化學性能模擬，進行研究熱啟動電池於不同操作溫度下之熱/質傳分析與電化學性能預測之評估；參考國外文獻所提供之非機密實驗結果，驗證所建立模型與研究方法之正確性與可行性，進而建立一套具多尺度且完整的設計模擬工具，以期能達到開發新式熔融鹽電解質熱電池之性能預測與優化目的。
熱電池又稱為熱激發電池，屬熔融鹽電池的一種，主要特徵為使用之電解質由共晶混合鹽所組成，當外部點火器啟動給予熱源時，透過各單電池的上下熱片傳遞大量熱源，迅速加熱使電解質呈熔融態，並使熱電池開始作電化學反應及放電。本論文首先從熔鹽電解質之二元材料出發，建構微觀尺度模型，利用計算量子力學理論計算原子分布/組成、勢能模型及離子擴散性等，並輔以分子動力學計算離子傳導率、熱傳導率、比熱與熔點等性質；接著運用計算流體力學方法建構巨觀尺度模型及代入微觀尺度模型所計算之性質，求解溫度分布及濃度場，並導入電化學理論，進而探討熱電池放電性能優化分析與評估熱效應造成之影響；另外亦嘗試針對熱電池失效模式(熱崩解及短路)作模擬與預測，探究其可能失效之原因與提出改善建議。
本論文最後提出具備成本低、安全性佳且不易造成環境破壞等優點之LiCl-LiBr-based三元、四元新型電解質材料，並從模擬結果中顯示它們可大幅提升電池性能。此外，四元材料不但可有效降低操作溫度(熔點低)，減少電池失效機率，亦可延長電池作用時間(壽命)。本論文之研究成果，除可有效降低熱電池研發成本，大幅縮減研發時程，並可作為未來研發設計新型熱電池之重要參考依據，從而提升台灣國防科技之競爭力。

The main purpose of this thesis is to set up a multi-scale simulation method which stems from computational quantum mechanics (CQM) to molecular dynamics (MD) to calculate material properties and ionic transport phenomenon. Furthermore, it is integrated with the computational fluid dynamics (CFD) technique to evaluate heat/mass transfer and electrochemical performance of thermal batteries. The simulation results have been compared with experimental data from non-confidential literatures. This is for verifying the correctness and accuracy of the simulation results. The next objective is to establish a multi-scale simulator to design the future novel thermal battery for defense purpose.
Thermal batteries are also named as thermally activated batteries, which employ eutectic salts as their electrolytes, so they are also called molten-salt batteries. At first, we construct a nano-scale model of binary molten-salt electrolytes to perform computational quantum mechanics (CQM) calculations. Secondly, we use molecular dynamics (MD) technique to calculate the ionic conductivity, thermal conductivity, specific heat, and melting point of the material. The CFD technique is then employed to predict the temperature distribution and concentration field in a macro-scale model. Finally, the heat transfer and thermo-electrochemical performance prediction of this battery is carried out. In addition, we also use this package to do the failure analysis (due to thermal runaway and short circuit) of various designs of thermal batteries.
A novel thermal battery, which employs LiCl-LiBr-based ternary and quaternary systems, has been designed using this multiscale simulation package. The results reveal that both the ternary and quaternary materials will enhance the battery performance, also the quaternary ones can reduce the operating temperature that implies quicker start up and longer working life. The multiscale simulation technique provides a low cost alternative to expensive experiments and is able to optimize the battery design under realistic operating conditions for future R&D.

R. A. Guidotti, and P. J. Masset, “Thermally activated (thermal) battery technology Part I：An overview,” J. Power Sources, 161, 1443-1449, 2006.
P. J. Masset, and R. A. Guidotti, “Thermally activated (thermal) battery technology Part II：Molten salt electrolytes,” J. Power Sources, 164, 397-414, 2007.
P. Masset, A. Henry, J. Y. Poinso, and J. C. Poignet, “Ionic conductivity measurements of molten iodide–based electrolytes,” J. Power Sources, 160, 752-757, 2006.
P. Masset, “Iodide-based electrolytes: A promising alternative for thermal batteries,” J. Power Sources, 160, 688–697, 2006.
P. Masset, S. Schoeffert, J. Y. Poinso, and J. C. Poignet, “LiF-LiCl-LiI vs. LiF-LiBr-KBr as Molten Salt Electrolyte in Thermal Batteries,” J. Electrochem. Soc., 152, A405-A410, 2005.
H. Okamoto, “Al-Li (Aluminum-Lithium),” Journal of Phase Equilibria and Diffusion, 133, 500-501, 2012.
R. A. Guidotti, and P. J. Masset, “Thermally activated (thermal) battery technology Part IV：Anode materials,” J. Power Sources, 183, 388-398, 2008.
W. Burgmann, G. Urbain, and M. G. Frohberg, “Iron-sulfur system in the iron monosulfide (pyrrhotite) region”, Mem. Sci. Rev. Met., 65, 567-578, 1968.
P. J. Masset, and R. A. Guidotti, “Thermally activated (thermal) battery technology Part IIIa：FeS2 Cathode Materials,” J. Power Sources, 177, 959-609, 2008.
P. J. Masset, and R. A. Guidotti, “Thermally activated (thermal) battery technology Part IIIb：Sulfur and oxide-based cathode materials,” J. Power Sources, 178, 456-466, 2008.
J. Sangster, and A. D. Pelton, “Phase Diagrams and Thermodynamics Properties of the 70 Binary Alkali Halide System Having Common Ions”, J. Phys.Chem. Ref. Data, 16, 509-561, 1987.
P. Masset, S. Schoeffert, J. Y. Poinso, and J. C. Poignet, “Retained molten salt electrolytes in thermal batteries,” J. Power Sources, 139, 356-365, 2006.
陳信宏(指導教授 吳乃立)，鋰鋁/二硫化鐵電池熱效應之理論分析，國立台灣大學化學工程研究所碩士論文，2000年。
C. Caccamo, and M. Dixon, “Molten alkali-halide mixtures: a molecular-dynamics study of Li/KCl mixtures,” J. Phys. C: Solid St. Phys., 13, 1887-1900, 1980.
M. Rovere, and M. P. Tosi, “Structure and dynamics of molten salts,” Rep. Prog. Phys, 49, 1001-1081, 1986.
M. Berkowitz, and W. Wan, “The limiting ionic conductivity of Na+ and Cl- ions in aqueous solutions: Molecular dynamics simulation,” J. Chem. Phys., 86, 376-382, 1987.
B. Morgan, and P. A. Maddena, “Ion mobilities and microscopic dynamics in liquid (Li, K) Cl,” J. Chem. Phys., 120, 1402-1412, 2003.
X. H. Duan, J. F. Li, W. J. Zhu, “Molecular dynamics simulation of ionic transport on molten Li–KCl interface,” Inter. J. Quan. Chem., 111, 3873-3880, 2011.
A. Bengston, H. O. Nam, S. Saha, R. Sakidja, and D. Morgan, “First-principles molecular dynamics modeling of the LiCl-KCl molten salt system,” Comput. Mater. Sci., Vol. 83, 362- 370, 2014.
P. Sindzingre, and M. J. Gillan, “A computer simulation study of transport coefficients in alkali halides,” J. Phys.: Condes. Matter, 2, 7033-7042, 1990.
N. Galamba, C. A. Nieto de Castro, and J. F. Ely, “Thermal conductivity of molten alkali halides from equilibrium molecular dynamics simulation,” J. Chem. Phys., 120, 08676-08682, 2004.
N. Galamba, C. A. Nieto de Castro, and J. F. Ely, “Shear viscosity of molten alkali halides from equilibrium and nonequilibrium molecular-dynamics simulations,” J. Chem. Phys, 122, 224501, 2005.
N. Galamba, C. A. Nieto de Castro, and J. F. Ely, “Equilibrium and nonequilibrium molecular dynamics simulation of the thermal conductivity of molten alkali halides,” J. Chem. Phys., 126, 204511, 2007.
N. Ohtori, T. Oono, and K. Takase, “Thermal conductivity of molten alkali halides: Temperature and density dependence,” J. Chem. Phys., 130, 044505, 2009.
N. Ohtori, M. Salanne, and P. A. Madden, “Calculations of the thermal conductivities of ionic materials by simulation with polarizable interaction potentials,” J. Chem. Phys., 130, 104507, 2009.
N. Galamba, and B. J. Costa Cabral, “First principles molecular dynamics of molten NaCl,” J. Chem. Phys., 126, 124502, 2007.
N. Galamba, and B. J. Costa Cabral, “First principles molecular dynamics of molten NaI: structure, self-diffusion, polarization effects, and charge transfer,” J. Chem. Phys., 127, 94506, 2007.
L. Zheng, S. N. Luo, and D. L. Thompson, “Molecular dynamics simulations of melting and the glass transition of nitromethane,” J. Chem. Phys., 124, 154504, 2006.
S. Fujiwara, F. Kato, S. Watanabe, M. Inaba, and A. Tasaka, “New iodide-based molten salt systems for high temperature molten salt batteries,” J. Power Sources, 194, 1180-1183, 2009.
S. Fujiwara, M. Inaba, and A. Tasaka, “New molten salt systems for high-temperature molten salt batteries LiF–LiCl–LiBr-based quaternary systems,” J. Power Sources, 195, 7691-7700, 2010.
S. Fujiwara, M. Inaba, and A. Tasaka, “New molten salt systems for high temperature molten salt batteries,” J. Power Sources, 196, 4012-4018, 2011.
R. Pollard, and J. Newman, “Transport Equations for a Mixture of Two Binary,” J. Electrochem. Soc., 126, 1713-1717, 1979.
R. Pollard, and J. Newman, “Mathematical Modeling of the Lithium-Aluminum,” J. Electrochem. Soc., 128, 491-502, 1981.
D. Bernardi, E. Powlikoski, and J. Newman, “A General Energy Balance for Battery Systems,” J. Electrochem. Soc., 132, 5-12, 1985.
D. Bernardi, E. Pawlikowski, and J. Newman, “Mathematical Modeling of LiAl/LiCl, KCl/FeS Cells,” J. Electrochem. Soc., 135, 2922-2931, 1988.
O. Shirai, T. Iwai, K. Shiozawa, Y. Suzuki, Y. Sakamura, and T. Inoue, “Electrolysis of plutonium nitride in LiCl－KCl eutectic melts,” J. Nucl. Mater., 277, 226-230, 2000.
M. C. C. Ribeiro, “Chemla Effect in Molten LiCl/KCl and LiF/KF Mixtures,” J. Phys. Chem. B, 107 4392-4402, 2003.
M. Bhattacharya, T. Basak, and K. G. Ayappa, “A fixed-grid finite element based enthalpy formulation for generalized phase change problems: role of superficial mushy region,” Int. J. of Heat and Mass Transfer, 45, 4881-4898, 2002.
P. Butler, C. Wagner, R. Guidotti, and I. Francis, “Long-life, multi-tap thermal battery development,” J. Power Sources, 136, 240-245, 2004.
S. Schoeffert, “Thermal batteries modeling, self-discharge and self-heating,” J. Power Sources, 142 361-369, 2005.
T. Yang, L. Cai, and R. E. White,” Mathematical modeling of the LiAl/FeS2 high temperature battery system,” J. Power Sources, 201, 322-331, 2012.
P. Singh, R. A. Guidotti, and D. Reisner, “ac impedance measurements of molten salt thermal batteries,” J. Power Sources, 138, 323-326, 2004.
R. A. Guidotti, F. W. Reinhardt, and J. Odinek, “Overview of high–temperature batteries for geothermal and oil/gas borehole power sources,” J. Power Sources, 136, 257–262, 2004.
R. A. Guidotti, F. W. Reinhardt, J. Dai, and D. E. Reisner, “Performance of thermal cells and batteries made with plasma-sprayed cathodes and anodes,” J. Power Sources, 160, 1456-1464, 2006.
N. Haimovich, D. R. Dekel, and S. Brandon, “A Simulator for System-Level Analysis of Heat Transfer and Phase Change in Thermal Batteries I. Computational Approach and Single-Cell Calculations,” J. Electrochem. Soc., 156, A442-A453, 2009.
N. Haimovich, D. R. Dekel, and S. Brandon, “A Simulator for System-Level Analysis of Heat Transfer and Phase Change in Thermal Batteries II. Multiple-Cell Simulations,” J. Electrochem. Soc., 162, A350-A362, 2015.
W. Kohn and L. J. Sham, “Self-Consistent Equation including Exchange and correlation Effects,” Phys. Rev., 140, A1133-A1138, 1965.
J. P. Perdew, K. Burke, and M. Ernzerhof, “Generalized Gradient Approximation Made Simple,” Phys. Rev. Letters, 77, 3865-3868, 1996.
M. C. Payne, M. P. Teter, D. C. Allen, T. A. Arias, and J. D. Joannopoulos. “Iterative Minimization Techniques for Ab Inito Total-energy Calculations: Molecular Dynamics and Conjugate Gradients,” Reviews of Modern Physics, 64, 1045-1097, 1992.
J. H. Irving, and J. G. Kirkwood, “The Statistical Mechanical Theory of Transport Properties. IV. The Equation of Hydrodynamics,” J. Chem. Phys., 18, 817-829, 1950.
B. J. Alder, and T. E. Wainwright, “Phase transition for A Hard Sphere System”, J. Chem. Phys., 27, 1208-1209, 1957.
M. P. Allen, D. J. Tildesley, “Computer Simulation of Liquids”, Oxford University Press, New York, 1987.
http://cbio.bmt.tue.nl/pumma/index.php/Theory/Potentials.
H. Sun, “COMPASS: An ab Initio Force-Field Optimized for Condensed-Phase Applications Overview with Details on Alkane and Benzene Compounds,” J. Phys. Chem. B, 102, 7338-7364, 1998.
H. Sun, P. Ren, and J. R. Fried, “The COMPASS Force field: Parameterization and Validation for Polyphosphazenes,” Comput. Theor. Polym. Sci., 8, 229, 1998.
D. Frenkel and B. Smit, “Understanding Molecular Simulation from Algorithms to Applications”, Academic Press, New York, 1996.
S. Nose, “A unified formulation of the constant temperature molecular dynamics methods.” J. Chem. Phys., 81, 511-519, 1984.
W. G. Hoover, “Canonical dynamics: Equilibrium phase-space distributions,” Phys. Rev. A, 31, 1695-1697, 1985.
O. C. Zienkiewicz, R. L. Taylor, P. Nithiarasu, “The Finite Element Method for Fluid Dynamics (7th edition),” The Finite Element Method for Fluid Dynamics, Oxford: Butterworth-Heinemann, 2014.
F. Torabi, V. Esfahanian, “Study of Thermal–Runaway in Batteries I. Theoretical Study and Formulation,” J. Electrochem. Soc., 158, A850-A858, 2011.
M. D. Segall, J. D. Lindan Philip, M. J. Probert, C. J. Pickard, P. J. Hasnip, S. J. Clark, M. C. Payne, “First-principles simulation: ideas, illustrations and the CASTEP code,” J Phys: Condensed Matter, 14, 2717-2744, 2002.
呂芳欽(指導教授 余樹偉、姚培智)，”鋰(鋁)/二硫化鐵熱電池之熱模擬”，國立中央大學化學工程研究所碩士論文，1988年。
紀尚甫(指導教授 洪哲文)，“熱電池電解質-熔融鹽混合物之第一原理分子動力學模擬分析”，國立清華大學動力機械工程研究所碩士論文，2014年。
C. F. Chen, H. Y. Li, and C. W. Hong, “Molecular Dynamic Analysis of High-temperature Molten-salt Electrolytes in Thermal Batteries”, CMC-Computers, Materials & Continua, vol. 46, no. 3, pp.145-163, 2015.
李皓宇(指導教授 洪哲文)，“熔融電解質熱電池之熱質傳性質與性能分析”，國立清華大學動力機械工程研究所碩士論文，2015年。
C. F. Chen, Y. C. Cheng, and C. W. Hong, “First Principles Molecular Dynamics Computation on Ionic Transport Properties in Molten Salt Materials”, CMES-Computers Modeling in Engineering & sciences, vol. 109, no. 3, pp. 263-283, 2015.
鄭宜佳(指導教授 洪哲文)，”第一原理分子動力學模擬熔融鹽電解質及熱電池性能之有限單元法分析”，國立清華大學動力機械工程研究所碩士論文，2016年。
C. F. Chen, Y. C. Cheng, and C. W. Hong, “Multi-scale Simulation and Design Analysis of Ionic Transport and Thermal Effect for High-temperature Molten Salt Batteries”, Applied energy. (Submitted).
G. J. Janz, C. B. Allen, R. M. Bansal, R. M. Murphy, R. P. T. Tomkins, “Physical properties data compilations relevant to energy storage. II. molten salts data on single and multicomponent salt systems,” National Bureau of Standards, U. S. Department of Commerce, New York, 1979.
F. Lantelme and P. Turq, “Ionic dynamics in the LiCl-KCl system at liquid state,” J. Chem. Phys., 77, 3177-3187, 1982.
C. Caccamo and M. Dixon, “Molten alkali-halide mixtures: a molecular-dynamics study of Li/KCl mixtures,” J. Phys. C: Solid State Physics, 13, 1887-1990, 1980.
Y. Nagasaka, N. Nakazawa, A. Nagashima, “Experimental determination of the thermal diffusivity of molten alkali halides by the forced Rayleigh scattering method. I. molten LiCl, NaCl, KCl, RbCl, and CsCl,” Inter. J. Thermo., 13, 555-574, 1992.
D. F. Williams, “Assessment of candidate molten salt coolants for the NGNP/NHI heat-transfer loop,” ORNL/TM-2006/69, Oak Ridge National Laboratory, Oak Ridge, TN, 2006.
C. H. San, C. P. Chiu, C. W. Hong, “First principles computations of the Oxygen reduction reaction on solid metal clusters,” CMC: Computers, Materials & Continua, 26, 167-186, 2011.
C. H. San, C. W. Hong, “Molecular design of the solid copolymer electrolyte-poly (styrene-b-ethylene oxide) for Lithium ion batteries,” CMC: Computers, Materials & Continua, 23, 101-118, 2011.
C. W. Hong, C. Y. Tsai, “Computational quantum mechanics simulation on the photonic properties of group-III Nitride clusters,” CMES: Computer Modeling in Engineering & Sciences, 67, 79-94, 2010.
C. W. Hong, W. H. Chen, “Computational quantum chemistry on the photoelectric characteristics of semiconductor quantum dots and biological pigments,” CMES: Computer Modeling in Engineering & Sciences, 72, 211-228, 2011.
C. H. Cheng, S. F. Lee, C. W. Hong, “Ionic dynamics of an intermediate-temperature Yttria-doped-Ceria electrolyte,” J. Electrochem. Soc., 154, E158-E163, 2007.
Cheng, C. H.; Chen, P. Y.; Hong, C. W. (2008): Atomistic analysis of hydration and thermal effects on proton dynamics in the Nafion membrane, J. Electrochem. Soc., 155, B435-.B442.