Effect of polymer binders on the electrochemical Performance of Al-doped lithium titanate electrode

Abstract

The investigation of polymers as binders of Al doped Li4Ti5O12 for Li-ion battery electrode is reported. Polimer binders such as Polyvinylidene fluoride (PVDF), polyvinyl alcohol (PVA), and Polytetrafluoroethylene (PTFE) were used to make electrode sheet. Al doped Lithium Titanate (Al-doped Li4Ti5O12) were used as electrode powders. Al doped Li4Ti5O12 powders were synthesized from LiOH.H2O, TiO2 and Al2O3 via solid state reaction. X-ray diffraction (XRD) was used to analysed phase and size of particle. Electrode sheets were manufactured by used active material, binders, and acetylene black in ratio 85:10:5 wt%. Electrode sheets were cut and assembled into coin cell batteries. Coin cell samples were characterized by EIS, cyclic voltammetry and charge-discharge to get electrochemical performance. XRD result reveals that there are two phases formed from final product such as Li4Ti5O12 and rutile TiO2. EIS diagram showed that sample with PTFE binder has the best conductivity with 3.10−5 S/cm. While, cyclic voltammetry and charge-discharge test showed sample with PVDF binder has the best chemical performance with good redox peaks and highest specific capacity about 110 mAh/g.