鋰-空氣電池在目前能源發展中，被視為極具發展性的儲能系統之一，主要是因為其理論能量密度就高於鋰離子電池的10倍，但目前仍處於研發階段，主要是放電過程中所產生的過氧化鋰會堆積於空氣電極中的孔洞，導致空氣無法順利參與反應，最後使電池無法繼續運作；因此改善過氧化鋰在空氣電極中的堆積情形，是鋰-空氣電池發展中極具重要的一個項目。本論文採用以密度泛函理論為基礎的第一原理計算軟體-VASP進行模擬，內容主要是針對過氧化鋰在石墨烯上找尋一最佳吸附狀態，並分析其束縛能。並建構不同缺陷密度之石墨烯結構，來探討在不同缺陷密度下對於過氧化鋰間束縛能的影響。模擬結果顯示，過氧化鋰分子容易吸附於石墨烯上方2.719Å處，並較容易吸附於5-8-5缺陷上方，而過氧化鋰間約在相距10Å後彼此間影響較小，推算石墨烯的5-8-5缺陷密度為4.16%。而在此缺陷密度下目前的製備方式是可達成的。

The lithium-air battery is one of the most promisiry technologies among various electrochemical energy storage system. It’s theoretical energy density of this battery is 10 times higher than the traditional Li-ion battery.However,during discharging process precipitation of reaction products Li2O2 on the carbonaceous electrode will block the oxygen pathway. Therefore, how to improve the accumulation phenomenon of Li2O2 particles
is main purpose of this study and significantly limits the capacity of this battery. In this study, the first principle calculation based on the density functional theory was adopted to investigate the adopted to investigate the adsorption condition of Li2O2 particles on grapheme by using VASP. Binding energies of the adsorption under different density of lattice defect in grapheme structure were evaluated individually. The numerical results show that Li2O2 prefers to nucleate and grow near the 5-8-5 lattice defects sites 2.719 Å above the grapheme surface. As the distance between two Li2O2 particles is longer 10 Å, the interaction between Li2O2 particles become significantly reduced. In other words, Li2O2 particles are easily to adsorb on grapheme structure with 4.16% of 5-8-5 lattice defect density.

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