為延長電池使用壽命與掌握電池的安全性，在本研究中，使用商用18650電芯來研究電池容量的衰減和老化機制，包括破壞性的電芯拆解及半破壞性的三極式載具測試。電芯拆解包括電芯內相關參數紀錄與分析、正負極組成、隔離膜材料、罐體設計、電性量測和電化學性質。電芯進行長圈數的老化循環並控制於恆溫40℃，材料的熱化學效應、化學結構和光譜分析也是研究之一，經過了解充放電循環後電芯內極捲的表面形貌、元素組成、電極材料的穩定性與電子價態的變化，透過未經老化之電芯與老化後電芯的比對，由晶體結構、形貌、元素分析和電化學性能來了解商業電池的降解機制。於半電池方面，透過充放電測試、循環伏安法和交流阻抗圖譜（EIS）進行綜合研究。於材料方面，採用掃描電子顯微分析（SEM）、感應耦合電漿原子放射光譜（ICP）、X光繞射（XRD）和傅立葉轉換紅外光譜（FTIR）進行交叉比對。於擬合部方面，利用OCV curve觀察電壓與容量的對應關係。延緩鋰離子電池老化的方式，除了材料改質、電解質改良外，也可以利用控制循環運行條件的方法來延長不同類型電池的壽命。希望透過更深入地了解老化機制以及相關性能測試方法的改進，實現鋰離子電池長期穩定的使用，滿足日益增長的應用需求。

The performance and lifespan of lithium-ion batteries have always been a key focus of research and development. In this study, commercially available 18650 batteries were used to investigate battery capacity decay and various degradation mechanisms. Over time and with charge-discharge cycles, lithium-ion batteries experience aging effects such as capacity decay and increased internal resistance, which directly impact the battery's performance and safety. In this study, destructive cell dismantling and semi-destructive three-electrode testing were included. The cell dismantling included the recording and analysis of relevant parameters in the cell, cathode and anode electrode composition, separator material, tank design, electrical measurement, and electrochemical properties. In this study, the cell with a constant temperature of 40 degrees C is used for a long time, and the long-term entry and exit of lithium ions will cause irreversible changes, which will reduce the cell usage. The thermochemical effect, chemical structure and spectral analysis of materials are also one of the researches, to understand the surface morphology and element composition of the electrode sheet after charging and discharging, the stability of the electrode material, and the change of the electronic valence state.
The degradation mechanisms of commercial cell were investigated by comparing the electrochemical performance of fresh and aging electrodes, including crystal structure, morphology, elemental composition, and electrochemical performance. In the half-cell part, a comprehensive study was carried out by charge-discharge procedure, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). In the material part, Scanning Electron Microscopy (SEM), Energy Dispersive spectroscopy (EDS), Inductively coupled plasma (ICP), X-Ray Diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) are used for cross-comparison. In the fitting part, use the OCV table to observe the correspondence between voltage and capacity. The strategy to delay the aging of lithium-ion batteries, in addition to material improvement, suppression of interfacial accumulation, and optimization of electrolytes, is also a method to control the cycle operating conditions of different types of batteries. It is hoped that through a deeper understanding of the aging mechanism and the improvement of related performance testing methods. Achieve long-term stable operation of lithium-ion batteries and meet growing application demands.

[1] "Lithium-ion battery " Wikipedia, The Free Encyclopedia. 19 June 2019, 06:32 UTC. Wikimedia Foundation, Inc. 3 December. 2013.
[2] Ashish Gogia et al. ”Binder-Free, Thin-Film Ceramic-Coated Separators for Improved Safety of Lithium-Ion Batteries” CS Omega (2021): 4204–4211
[3] Han, Xuebing, et al. "A review on the key issues of the lithium ion battery degradation among the whole life cycle." ETransportation 1 (2019): 100005
[4] J. Vetter, P. Novák, M.R. Wagner, et al. ”Ageing mechanisms in lithium-ion batteries” J Power Sources 147 (2005): 269-281
[5] N. Lin, Z. Jia, Z. Wang, et al. ”Understanding the crack formation of graphite particles in cycled commercial lithium-ion batteries by focused ion beam-scanning electron microscopy” J Power Sources 365 (2017): 235-239
[6] J. Christensen, J. Newman “Effect of anode film resistance on the charge/ discharge capacity of a lithium-ion battery” J Electrochem Soc 150 (2003): 1416-A1420
[7] Yirui Zhang, Yu Katayama, et al. ”Revealing electrolyte oxidation via carbonate dehydrogenation on Ni-based oxides in Li-ion batteries by in situ Fourier transform infrared spectroscopy” Energy Environ (2020):183-199
[8] L. Patnaik, A. Praneeth, S.S. Williamson “A closed-loop constant-temperature constant-voltage charging technique to reduce charge time of lithium-ion batteries” IEEE Trans. Ind. Electron 66 (2018): 1059-1067
[9] J. Sieg, J. Bandlow, T. Mitsch, et al. “Fast charging of an electric vehicle lithium-ion battery at the limit of the lithium deposition process” J. Power Sources 427 (2019): 260-270
[10] U.R. Koleti, T.N.M. Bui, T.Q. Dinh, et al. “The development of optimal charging protocols for lithium-ion batteries to reduce lithium plating” J. Energy Storage 39 (2021): 102573
[11] Haijun Ruan, Jorge Varela Barreras, Timothy Engstrom, Yu Merla ,et al. “Lithium-ion battery lifetime extension: A review of derating methods” J. Power Sources 563 (2023): 232805
[12] Victor Agubra, Jeffrey Fergus “Lithium Ion Battery Anode Aging Mechanisms” Materials (2013): 1310–1325.
[13] Rui Xiong “Lithium-ion battery aging mechanisms and diagnosis method for automotive applications: Recent advances and perspectives” Renewable and Sustainable Energy Reviews 131(2020): 110048
[14] batterywali “Calendar life VS Cycle life” (2018)
[15] Battery university “BU-304: Why are Protection Circuits Needed?”(2023)
[16] Christoph R. Birkl, et al. “Degradation diagnostics for lithium ion cells” J. Power Sources 341(2017): 373-386
[17] Xing Li et al.” Stability of polymeric separators in lithium metal batteries in a low voltage environment” Journal of Materials Chemistry A 12(2018)
[18] Team Xometry “Polyethylene (PE): Structure, Properties, and Applications”
[19] Jiuqing Li, Yong Qin, et al. “Structural characteristics and evolution of meta-anthracite to coaly graphite: A quantitative investigation using X-ray diffraction, Raman spectroscopy, and high-resolution transmission electron microscopy” Fuel 333 (2023): 126334
[20] Thomas Waldmann, et al.” Review—Post-Mortem Analysis of Aged Lithium-Ion Batteries : Disassembly Methodology and Physico - Chemical AnalysisTechniques” J The Electrochemical Society 163(2016): 2149-2164
[21] Pengcheng Zhang, Tao Yuan, et al.” Influence of Current Density on Graphite Anode Failure inLithium-Ion Batteries” J The Electrochemical Society 166 (2019): 5489-5495
[22] Xuemin Li , Andrew M. Colclasure, et al.” Degradation mechanisms of high capacity 18650 cells containing Si-graphite anode and nickel-rich NMC cathode” Electrochimica Acta 297(2019):1109-1120
[23] Victor Agubra , Jeffrey Fergus ” Lithium Ion Battery Anode Aging Mechanisms” Materials (2013): 1310-1325
[24] Han Wang , Jay F. Whitacre. “ Inhomogeneous aging of cathode materials in commercial 18650 lithium ion battery cells ” J Energy Storage 35(2021): 102244
[25] Peter Keil, Simon F. Schuster, et al.” Calendar Aging of Lithium-Ion Batteries” J. Electrochem 163 (2016): 1872
[26] Dominik Petz, Volodymyr Baran, et al.” Aging-Driven Composition and Distribution Changes of Electrolyte and Graphite Anode in 18650-Type Li-Ion Batteries” advanced energy materials 12 (2022): 2201652
[27] Hyungyeon Cha , Jaeseong Hwang, et al.” Calendar Aging of Ni-rich Cathode in High-Energy Lithium-ion Batteries” SSRN (2022)
[28] Mir Wasim Raja, et al.” The Paper-Based Ceramic Separator for Lithium-Ion Batteries and the Process Scale-Up Strategy” Energy Mater (2022): 5841–5854
[29] Agus Purwanto, Cornelius Satria Yudha, et al.” NCA cathode material: synthesis methods and performance enhancement efforts.” Materials Research Express(2018): 122001
[30] Ding, Yuanli, et al. "Automotive Li-ion batteries: current status and future 250 perspectives." Electrochemical Energy Reviews 2.1 (2019): 1-28
[31] Loveridge, Melanie J., et al. "Looking deeper into the Galaxy (Note 7)." Batteries 4.1 (2018): 3.
[32] Noori, Mehdi, Stephanie Gardner, and Omer Tatari. "Electric vehicle cost, emissions, and water footprint in the United States: development of a regional optimization model." Energy 89 (2015): 610-625.
[33] 黃可龍, 王兆翔, 劉素琴「鋰離子電池原理與技術」，五南出版社，2010年5月
[34] Panasonic ideas for life “NCR18650b lithium-ion / nnp + hrl technology”