Electrochemical Performance Enhancement of VRLA Gel Electrolytes via Polythiophene Addition


Mira Z., GENÇTEN M.

Journal of the Electrochemical Society, cilt.173, sa.7, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 173 Sayı: 7
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1149/1945-7111/ae568f
  • Dergi Adı: Journal of the Electrochemical Society
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, INSPEC
  • Anahtar Kelimeler: electrochemical optimization, ion diffusion path, polythiophene additive, polythiophene gel electrolyte, VRLA-gel type batteries
  • Yıldız Teknik Üniversitesi Adresli: Evet

Özet

In this study, polythiophene, a conductive polymer synthesized through chemical oxidative polymerization, is used for the first time in the literature as an additive to a fumed silica–based gel electrolyte in valve-regulated lead–acid batteries to improve electrochemical performance, charge-transfer characteristics, and ion diffusion pathways. Electrochemical analyses, including cyclic voltammetry, electrochemical impedance spectroscopy, and Tafel extrapolation, are employed to optimize gel systems prepared using three parameters: additive content, stirring duration, and stirring rate. The gel electrolyte containing 0.2 wt% polythiophene, prepared at a stirring time of 30 min and a stirring rate of 500 rpm, exhibits the optimal electrochemical performance. Battery performance is evaluated through galvanostatic charge–discharge experiments, yielding a specific capacity of 51.3 mAh g−1 at a current density of 5 mA g−1, with a capacity retention of 88% over 200 cycles at 10 mA g−1. The incorporation of polythiophene reduces the charge-transfer resistance and enhances ion diffusion, thereby improving the overall electrochemical performance. These results demonstrate that polythiophene is a promising additive for gel electrolytes, offering improved efficiency and cycling stability in valve-regulated lead–acid battery systems.