雙離子對在不同方式上的應用具有不同的作用性，可以利用它們實現更寬的電化學電位窗口、更高的導離子度、更穩定的循環壽命以及卓越的能量密度和功率密度。羧基丙氨酸甜菜鹼（CB）具有比其他離子對更好的水合性質和更強的作用力，被認為是優化電解液的主要貢獻因素。從實驗結果中發現，少量添加雙離子確實可以增強它們的導離子度和電容量與穩定性，而過高的濃度則會導致雙離子之間發生自聚效應，因此選擇了含有相同性質並含有雙鍵的羧基丙氨酸甲酰胺（CBAA）來做為整個實驗的主軸。除了將少量的電解質作為添加劑外，還可以通過自由基聚合將雙離子固定在鏈上，形成pCBAA，以藉此希望減少自聚效應的影響並更廣泛地擴大電化學電位窗口。然而，鏈與鏈之間的吸引力無法完全避免，導致其中分散的pCBAA對離子移動的通道影響甚大。最後，我們通過添加少量的交聯劑來解決這個問題，不僅加寬電化學電位視窗，根據交聯劑支撐的空間提供了穩定的離子通道，使自聚效應大大的降低，同時維持雙離子原有的特性，使離子在其中穩定且快速的移動。

The first part of the study analyzed the zwitterion CBAA as an electrolyte additive by adding different weight percentages. It was found that for a fixed range of additive amount, the zwitterion could help the ions in the electrolyte move more quickly due to its characteristic of containing both anions and cations. The conductivity increased with the increase of the additive amount, reaching a maximum of 5.66 mS/cm when adding 10% CBAA. Raman test results showed that as the zwitterion ratio increased, the originally contributing THB gradually shifted towards NTHB and FHB. This indicates a tendency towards ideal capacitance performance in cyclic voltammetry testing, and a slight reduction in the influence of water molecules. The discharge capacitance retention rate reached 91% when changing the current density, and the cycle life of 5000 cycles reached 94.1% of the initial capacitance.
The second part of the study aimed to improve the first part by forming the zwitterion into a linear polymer pCBAA, which fixed the CBAA to capture free water molecules in the solution and expand the shortcomings of its electrochemical potential window. Raman spectroscopy showed that water distribution almost completely shifted from THB to NTHB and FHB, indicating a stronger water suppression ability in the electrolyte. In cyclic voltammetry testing, the responsive interval was significantly extended to 1.4 V. However, due to the self-assembly effect between chains, resulting in a capacitance retention rate of only 76.0% under 10 A/g, and a decrease in long-term stability to 82.0%. Therefore, a networked polymer pCBAA-co-PEGDA was formed, which exhibited the highest conductivity of 5.8 mS/cm. The FHB ratio was as high as 81.6%, which confirmed that adding a small amount of cross-linking agent created space to effectively suppress self-assembly and maintained the characteristics of CBAA itself, such as good water-grabbing properties, enabling the electrochemical potential window to be maintained at 1.4 V and helping ions to move quickly in the network structure. The capacitance retention rate under high discharge current density could be maintained at 91.7%, and even after 5000 cycles of cycle life testing, it still contained 96.8% of the initial capacitance.

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