同時具備高安全性以及儲能性佳等功用之鋰離子電池成為備受關注的綠色能源，鋰離子電池已經廣泛地運用在各種電子產品，而具有高能量密度的鋰離子電池則被視為電動汽車（Electric Vehicle）和油電混合動力汽車（Hybrid Electric Vehicle）的理想動力源，這顯示安全性更為重要。
本研究擬開發一新穎安全之反應性聚合物添加劑，藉由對苯二胺(PDA)與雙馬來醯亞胺(BMI)進行邁克爾加成反應產生之衍生物(BA2)，並且添加單水氫氧化鋰對其電化學性能進行優化，其中包含具精準活化溫度為 120 ℃之封閉型多元異氰酸酯(B3)，目的是在高溫時能夠快速地進行反應，使一薄膜緻密包覆於正極材料表面，進而終止電化學反應並避免熱失控發生。
本研究透過熱示差掃描分析(DSC)、熱重分析(TGA) 、X光繞射儀(XRD)以及掃描式電子顯微鏡(SEM)等儀器對於反應性聚合物添加劑進行材料性質分析，接著透過電化學儀器進行循環伏安法分析(CV)、充放電測試(Charge/Discharge test)、循環壽命測試(Cycling test)及交流阻抗分析(EIS)，闡明添加劑對於各電芯樣品之電化學性能影響，並使用四點探針電阻測量器(Four Point Prober)及交流阻抗分析(EIS)，探討添加劑於表面薄層之安全性分析。
研究結果表明，1.5% BA2Li-B3電芯樣品在循環壽命測試中與Benchmark相當，且優於Blank樣品。BA2Li-B3之熱裂解溫度較Benchmark低，推測是對苯二胺(PDA)的影響。在四點探針電阻實驗與交流阻抗分析中，在高溫後BA2Li-B3樣品之電阻明顯高於Blank樣品，說明此添加劑具有效的安全啟動機制。整體而言，BA2Li-B3 高分子添加劑能有效提高鋰離子電池之安全性，並且相較於BA2-B3之電池性能表現更為優異，具有作為正極材料安全性添加劑可行性。

This work aims to develop an innovative reactive polymer additive for improving the safety of lithium-ion batteries. Nowadays, lithium-ion batteries are widely used in electronic products. Furthermore, lithium-ion batteries with high energy density have gained significant attention as a green energy source, particularly for electric vehicles (EVs) and hybrid electric vehicles (HEVs) and energy storage system applications. Thus, ensuring their safety is of utmost importance.
This study focuses on the synthesis of a novel reactive polymer additive, abbreviated as BA2Li-B3. BA2Li-B3 is derived from the Michael addition reaction of p-phenylenediamine (PDA) and bismaleimide (BMI). By incorporating lithium hydroxide monohydrate and a blocked polyisocyanate (B3) with a precise activation temperature of 120°C into the intermediate of PDA-BMI, the electrochemical performance of the additive is optimized. The objective of this work was to achieve a dense thin film coated on the positive electrode material's surface.
Several techniques were employed to characterize the reactive polymer additive's material properties. Differential scanning analysis (DSC), thermogravimetric analysis (TGA), X-ray diffractometer(XRD), and scanning electron microscopy (SEM) were utilized to examine the thermal behavior and morphological characteristics of the additive. The electrochemical performance of the lithium-ion batteries with the additive inside was assessed using various tests. Cyclic voltammetry (CV), charge/discharge tests, cycle life tests, and AC impedance analysis (EIS) were conducted to evaluate the redox reaction behavior, energy storage and release capabilities, longevity overcharge/discharge cycles, and impedance characteristics of the batteries, respectively.
The research findings indicate that the 1.5% BA2Li-B3 cell sample performs on par with the benchmark in the cycle life test and outperforms the blank sample as well. The four-point probe resistance test and Electrochemical Impedance Spectroscopy test reveal that the BA2Li-B3 sample exhibits significantly higher resistance than the blank sample at elevated temperatures, indicating an effective safety mechanism.
In summary, the BA2Li-B3 polymer additive effectively enhances the safety of lithium-ion batteries while it demonstrates a superior battery performance compared to BA2-B3. This research also shows the feasibility of BA2Li-B3 as a positive electrode material safety additive and contributes to the ongoing efforts to develop safer and more efficient lithium-ion batteries for sustainable energy applications.

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