動力電池落下衝擊分析研究

Analysis of Electric Vehicle Batteries Subjected to Shock Loading

蘇汶航(Wen-Hang Su)

指導教授 ： 鄭榮和

國立臺灣大學/工學院/機械工程學研究所/碩士(2012年)

https://doi.org/10.6342/NTU.2012.01533

摘要

近年來許多國家皆展開電動車相關領域的研究，而在電動車各種研究議題中，安全問題是最為重要的，電動車動力電池經常使用的鋰電池，擁有能量密度與功率密度高之優點，然而鋰金屬的高活性卻也帶來相當高的危險性，目前針對電池安全性的研究重點皆放在電路保護、電池芯化學性質與熱管理上，而較少討論機械性的議題，然而無論電路保護等防護多麼完善，若在電池模組機構設計上有所缺陷，則還是有可能產生失效之情形。

本研究針對18650電池芯之動力電池模組，受落下衝擊負載之情形進行分析，尋找衝擊時電池模組最可能發生破壞並造成失效的關鍵元件，並使用有限元素軟體輔助模擬電池模組落下衝擊之情形，並以實驗驗證分析結果之準確性，再配合田口法以探討電容量1kWh之動力電池模組中，各機構設計參數改變，對於衝擊中關鍵元件最大應力的影響，藉此歸納出提升動力電池模組承受衝擊負載之設計方針。

18650電池芯之動力電池模組在受衝擊時，導電元件鎳片會產生最大應力並有破壞的可能性，接而導致電池模組的失效，而經由本研究分析，挑選合適之電池模組機構設計參數，不須大幅度的變更電池模組設計，就可以有效降低鎳片的應力，進而提升動力電池之可靠度。

關鍵字

動力電池模組 ； 18650電池芯 ； 落下衝擊 ； 有限元素分析

並列摘要

In recent years, the issues of electric vehicles (EV) have been researched in many countries. Also, the safety is the most important issue in a variety of researches in the EV. Lithium battery which often used in the EV contains the advantages of high energy and power density. However, high activity of lithium metal also brings a very high risk. At present, the investigation on battery security merely focus on the circuit protection, chemical properties of battery cells and thermal management, but less to discuss mechanical parts. No matter how secure the circuit and other protection are, it still remains the possibility of failure when there are defects in the battery module mechanical design.

The research analyzed the 18650 cell battery module subjected to shock loading. To find out the key components which is broken and lead to module failure during shock loading. The research was using the finite element software simulates the situation of battery module be shocked. And then conduct an experiment to verify the accuracy of the simulation results. After that, discussing the various mechanical design parameters of the 1kWh battery module to change the maximum stress during shocked of the key component with the Taguchi method. By the method, a design principle is proposed to raise loading to withstand shock of the power battery module.

During 18650 cell battery module subjected to shock loading, the maximum stress occurred at the conductive component－nickel plate, and had the possibility of damage causing the battery module failure. And through researched and analysis, selecting the appropriate mechanical design parameters could reduce the stress of the nickel plate effectively, and enhanced the Reliability of the power battery.

並列關鍵字

power battery module ； 18650 cell ； shock test ； finite element analysis

參考文獻

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