無陽極鋰電池（AFLB）可以透過最少量的活性鋰，來降低在電極表面上樹枝狀結構的生長，進而提升鋰金屬電池的安全性；藉由減少鋰金屬的使用，節省能源，並降低其生產成本，使得AFLB在新一代鋰金屬電池中引起廣泛的注意和討論。然而，沒有額外的鋰離子來填補無活性的鋰和固體電解質膜(SEI)所消耗的鋰離子，可以預期AFLB的循環壽命較差，所以需要高濃度的電解質來補償鋰的損失。在這項研究中，我們使用第一性原理分子動力學研究鋰離子（來自LiPF6鋰鹽）在混合有機溶劑EC和DEC（1：1）中的結構，並考慮低濃度（1M）和高濃度（3.6M）的電解質來探討濃度對於電解質分解反應的影響。我們使用銅金屬當作陽極電極，並研究高濃度電解質在鋰金屬表面、銅金屬表面，和鋅摻雜銅金屬表面上的分解反應。此外我們透過外加電子(4個電子)於整個計算系統中，模擬現實電池充電中發生的電化學反應，比較帶電和未帶電銅金屬和鋅摻雜銅金屬表面，我們可以發現電解質在中性環境下不會分解並維持熱穩定性；然而，電解質中的鹽和溶劑都傾向於在過量電子環境下分解。此外計算結果可以得知鋅摻雜銅金屬表面可以促使主要SEI成分(LiF)的形成並抑制溶劑分解。除了比較上述帶電系統下電解質的分解反應，我們進一步探討電解質在帶電鋰金屬表面上的分解狀況，結果顯示Li金屬具有高反應性，導致鋰鹽和溶劑容易發生分解反應，且不易控制其在鋰金屬表面形成SEI膜的組成成分。

Anode Free Lithium batteries (AFLB) are an intriguing and underexplored possibility for realizing lithium metal batteries. A lack of lithium metal can save energy, the cost associated with anode production and safety issues may be improved by the minimum amount of active lithium. However, no excess Li compensates for the loss of Li ions that forms the dead lithium and other SEI compositions. Thus, the cycle life of AFLB is predictably low, AFLB needs a high concentration electrolyte to compensate for lithium loss. SEI layer basic evolution is driven chemical reactions by electron transfer, and continuous SEI formations consume lithium inventory and reducing cell capacity. In this study, we use first-principles molecular dynamics to examine the solvation of Li ions (from LiPF6 salts) in the dual organic solvents EC and DEC (1:1) and considered both low (1M) and high (3.6M) concentrations of electrolyte and studied the concentration effects on the decomposition reactions. We also explored high concentrations of electrolyte decomposition reactions in the presence of Cu current collector, Zn doped Cu current collector and Li metal anode surfaces. Furthermore, we analyzed the electrolyte chemical stability on the different surfaces under the electron-rich environment (excess of 4 electrons). We found that the neutral electrolyte is electrochemically stable in the anode free lithium metal batteries. However, both salt and solvent in the electrolyte tend to decompose under the electron-rich environment on the pristine Cu surface. Whereas, the doping of Zn on the Cu current collector surface can facilitate the main SEI component formation and inhibit the solvent decomposition. We also compared the electrolyte decomposition in the AFLB and lithium metal anode under electron-rich environment. Our results demonstrate that it is hard to control the electrolyte decomposition products in the lithium anode surface because of the high reactivity of Li metals in the anode.

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