Transport property measurements of polymer electrolytes

• Straightforward electrochemical methods for determining the transport properties (bulk ionic conductivity, salt diffusion coefficient, and cation transference number) of polymer electrolytes are described herein. The new technique for measuring t0+ is:based on concentrated solution theory, and requires no assumptions to be made concerning ideality of the solution. The experimental methods are described and results on representative polymer electrolyte systems are presented in this paper. Cation transference numbers are found to be salt-concentration dependent and considerably less than unity or even negative over a wide concentration range. This implies that the cationic current is mainly carried by complexed ions. The presence of associated ionic species in the present systems is confirmed by Raman spectroscopic evidence. Finally, the practical effects of a negative t0+ on cell operation and implications for device design are discussed. 

Ämnesord

NATURVETENSKAP  -- Fysik -- Den kondenserade materiens fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences -- Condensed Matter Physics (hsv//eng)

Nyckelord

polymer electrolyte

transport properties

transference number

Raman spectroscopy

diffusion

ionic-conductivity

molecular-weight

lithium

triflate

sodium

association

separation

electrodes

batteries

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)