鋰硫電池生命週期內之可靠度分析

Reliability Analysis of Lithium-Sulfur Batteries in Their Life Cycles

周伯彥(Bo-Yen Chou)

指導教授 ： 吳文方

國立臺灣大學/工學院/工業工程學研究所/碩士(2015年)

https://doi.org/10.6342/NTU.2015.00025

摘要

本論文旨在建立一個考慮不確定性、以可靠度為基礎的數學模型來描述數種鋰硫電池的退化現象，文中，首先提出一具有四種狀態的馬可夫過程模型，以描述擁有不同正極（如石墨、金屬氧化物及金屬）鋰硫電池電容量隨充放電次數下降的趨勢，讓我們能以馬可夫矩陣模擬並瞭解鋰硫電池電容量的衰退機制以及充放電時的變異情況。而後，本論文依據該模型分析電池的壽命分佈、可靠度、變異數及保固情形等，以量化可靠度觀點，求得電池在任意時間的失效機率。本論文透過數值分析發現，所建構的馬可夫模型確可廣泛描述各種鋰硫電池的可靠度。本論文除以上分析外，也以馬可夫模型佐證他人研究所言「金屬物質於正極與硫化物作用可強化鋰硫電池壽命」，尤其以鎳基板做為正極，確實能夠成功限制電子內部多硫化物的產生，延長鋰離子於活躍狀態時間，進而延長鋰硫電池壽命。

關鍵字

鋰硫電池 ； 健康狀態 ； 退化 ； 殘餘壽命 ； 馬可夫過程 ； 可靠度分析

並列摘要

The purpose of this research is to utilize reliability engineering theory to investigate the effects of uncertain factors on the degradation of lithium-sulfur batteries. A Markov process model is constructed to describe the capacity and capacity degradation of the battery and evaluate the distribution of its remaining life. A four-state model is found to be able to describe the fading curves of most lithium-sulfur battery systems having different cathode materials. It gives detailed insights into the fading mechanisms of lithium sulfur cells. The model is then used for the analysis of life distribution and reliability of the battery based on test or observed data. A warranty analysis of the battery is also presented. It is found that the proposed Markov model is able to describe the reliability of various kinds of lithium-sulfur battery. It is also verified through the model that metal oxide has a positive effect for lithium-sulfur batteries with regard to their lives.

並列關鍵字

Lithium-Sulfur Battery ； State of Health ； Degradation ； Remaining Life ； Markov Process ； Reliability Analysis

參考文獻

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