這項研究引入雙離子對生物高分子進行修飾分別作為水膠電解質和黏著劑來構建超級電容器，並在低溫下實現優異的電化學性能。羧基化殼聚醣（CCS）和羧甲基纖維素（CMC）分別與磺基甲基丙烯酸鹽（SBMA）進行麥克加成反應，合成CCS-SBMA和CMC-SBMA，分別用於水膠電解質和黏著劑。於所有電解質中， CCS-SBMA浸泡於12m NaClO4溶液中其膨脹比達8.5時，於低溫下具有優異的離子導電率。令人驚訝的是，CCS-SBMA-12於-40°C下的離子導電度 (9.48 mS cm−1）仍然高於CCS-10於25°C下的離子導電度（8.23 mS cm−1）。基於上述，CCS-SBMA-12被用於超級電容器中的水膠電解質進行低溫測試。
CMC以及CMC-SBMA分別作為超級電容器之黏著劑且將之命名為SCs-CMC和SCs-CMC-SBMA。由差式掃描熱量儀中得知，CMC於0°C至-20°C中存在一個結晶峰，因此SCs-CMC於低溫下由交流阻抗儀進行測試時，其阻抗值隨溫度降低而急遽增加。相反地，SCs-CMC-SBMA的阻抗值於0到-15 °C之間幾乎維持固定值，而於-15到-20 °C之間僅略有上升。CMC-SBMA在低溫下的結晶度降低，說明該超級電容器於-20 °C時可以達到80 F g−1的優異比電容。本研究突顯了如何設計一超級電容器於低溫下具有優越的電化學性能。

This research introduces zwitterion bearing biopolymers as hydrogel electrolytes and electrode binders for supercapacitors which possess superior performance at low temperature. Carboxylated chitosan (CCS) and carboxymethyl cellulose (CMC) undergo oxa-Michael addition with sulfobetaine methacrylate (SBMA) to obtain CCS-SBMA and CMC-SBMA as hydrogel electrolytes and electrode binders, respectively. According to the electrolytes, CCS-SBMA under 12m sodium perchloride as swelling ratio to 8.5 (CCS-SBMA-12) demonstrates the superior performance on ionic conductivity at low temperature. Surprisingly, the ionic conductivity value for CCS-SBMA-12 of 9.48 mS cm−1 at -40oC is still higher than one for CCS-10 of 8.23 mS cm−1 at 25oC. Accordingly, CCS-SBMA-12 is used as hydrogel electrolyte for supercapacitor.
Subsequently, CMC and CMC-SBMA are applied as electrode binder for supercapacitor denoted as SCs-CMC and SCs-CMC-SBMA. From the Electrochemical impedance spectroscopy analysis at low temperature, the resistance of SCs-CMC increases significantly from 0 to -20 oC due to the crystallization of CMC, coincided with differential scanning calorimetry analysis for CMC. Conversely, the resistance of SCs-CMC-SBMA nearly maintains from 0 to -15 oC and increases slightly from -15 to -20 oC. Substantially, less crystallization of CMC-SBMA at low temperature presents that supercapacitor can possess superior performance on capacitance of 80 F g−1 at -20 oC. This study lights up the superior performance of supercapacitor at low temperature.

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