Polymer Electrolytes for Electrochromics and Electrochemical Devices

Polymer electrolyte plays an important role in the development of electrochromics and other redox active electrochemical devices such as energy storage or actuators. The mobility ions enable high ionic conductivities, controlling the device switching kinetics and reversibility. In our work, photocurable solid-state poly(ionic iquid) (PIL) ionogel and polyvinly alcohol (PVA) based organohydrogel have been developed for flexible and stretchable electrochromic devices, respectively. The PIL ionogel is formed using in-situ polymerization.[1] The resultant ECDs are of high color contrast, high thermal stability and cycling stability. Flexible form factor and deformability of the ECDs can be achieved. Meanwhile, the PVA organohydrogel was used in the self-powered and light-adaptable stretchable electrochromic display.[2]
More recently, we realize photocurable redox-active solid-state electrolyte for flexible electrochromic device with a redox mediator, utilizing an inkjet-printed WO₃/ITO/PET working electrode and a carbon-edge/ITO/PET counter electrode. In addition, a reversible photoswitchable polymer composite electrolyte has been investigated to realize redox active energy storage devices such as supercapacitors. Impressive ionic conductivity modulation can be achieved with photoswitchable electrolyte, delivering fast responsive photo-controllable energy conversion devices.

References:
1. W. C. Poh, A. L-S. Eh, W. Wu, X. Guo, P. S. Lee, Adv. Mater. 2022, 34, 2206952.
2. W. Wu, W. C. Poh, J. Lv, S. Chen, D. Gao, F. Yu, H. Wang, H. Fang, H. Wang, P. S. Lee, Adv. Energy Mater., 2023, 13, 2204103.