鋰電池鋁殼之破壞分析及安全性改善研究

Abstract

本文旨在探討鋰電池的安全測試、強度分析，因現今鋰電池常出現發生爆炸而危害到使用者的安全，因此本文將探討提高其鋰電池安全性並且加強其強度的方法， 首先經過穿刺和過度充電的實驗來探討其行為、安全性 ，並利用分析方法來了解其鋰電池的變形情況、受力狀況、破壞情形，經過分析、實驗比對其準確性，隨後即加入強化鋰電池並且提高安全性的設計，而在做這些設計的前提需不嚴重的影響到鋰電池基本的輕、薄、小的原則，經過設計後則比較在不同設計下鋰電池的強度和在過度充電以後爆裂時的破壞情形，最後選擇最佳的改善方法，以最佳的設計方法設計出能夠有效的減小鋰電池在爆裂的情況下所為害到人身安全的範圍並且強化鋰電池的外殼以減少鋰電池受外力作用而失效的可能性。

The purpose of this thesis is to study the failure process of the aluminum case of a lithium battery subjected to indentation or overcharge. Lithium batteries may explode due to the penetration of a foreign object or overcharge. The explosion of a lithium battery can cause significant damage. Therefore, the safety of lithium batteries has become an important topic of research. In this thesis, the load-displacement curve of the aluminum case of a lithium battery penetrated by a nail was constructed via both theoretical and experimental approaches. In the theoretical study, a finite element model is established for predicting the deformation of the case and a strain energy failure criterion is used to estimate the failure strength of the aluminum case. The experimental results have validated the suitability of the finite element model. The finite element model is then used to study the overcharge and explosion of the battery. Different reinforcement patterns using glass-fabric composites have been adopted to improve the safety of the battery. It has been shown that a proper reinforcement of the case using glass-fabric composites can significantly enhance the safety of the battery.