Hostname: page-component-78c5997874-g7gxr Total loading time: 0 Render date: 2024-11-14T17:31:02.716Z Has data issue: false hasContentIssue false

Conductivity and Morphology of Hybrid Electrolytes Based on Blends of Pvdf With PEO-co-PPO Copolymers

Published online by Cambridge University Press:  10 February 2011

H.P. Wang
Affiliation:
Department of Chemistry, Temple University, Philadelphia, PA 19122
J. B. Kejha
Affiliation:
Lithium Technology Corporation, Plymouth Meeting, PA
Y.K. Yarovoy
Affiliation:
Department of Chemistry, Temple University, Philadelphia, PA 19122
S.L. Wunder
Affiliation:
Department of Chemistry, Temple University, Philadelphia, PA 19122
Get access

Abstract

Hybrid film electrolytes with high room temperature conductivity have been prepared by casting solutions of PVDF-HFP copolymers with PEO-PPO block copolymers and PEO oligomers followed by activation of the polymer blend films in electrolyte solutions. The morphology and conductivity of these solid electrolytes were studied as a function of concentration, molecular weight and sequence order (in the case of PPO-co-PEO-co-PPO or PEO-co-PPO-co-PEO) of the PEO and PEO-PPO copolymers, and also of the casting solvent and evaporation rate of the casting solvent. Structural studies of PVDF-HFP/PEO and PVDF- HFP/PPO-co-PEO blend films (SEM, DSC) before activation with lithium salt electrolyte may indicate the occurrence of spinodal decomposition in the films during slow evaporation of the casting solvent. As a result of spinodal decomposition, an interpenetrating bi-continuous phase may evolve with microphase separation between PVDF-HFP and PPO-PEO phases, in which the PVDF phase provides mechanical support and the PPO-PEO phase pfovides a conductive path.

Type
Research Article
Copyright
Copyright © Materials Research Society 1999

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Alamgir, M., Abraham, K. M., Lithium Batteries, Developments and Perspectives, (Elsevier Science Publishers, Amsterdam, 1994).Google Scholar
2. Andrieu, X. and Jehoulet, C., Boudin, F. and Olsen, I.I., in Proceedings of the 38th Power Sources Conference, Cherry Hill, New Jersey, June, 1998, p.266269.Google Scholar
3. Imhof, A., Pine, D. J., Advanced Materials 10, 697 (1998).Google Scholar
4. Gozdz, A.S., Tarascon, J.M. and Warren, P.C., U.S. Patent No.5 460 904 (24 October, 1995); A.S.Gozdz, C.N.Schmutz, J.M.Tarascon and P.C.Warren, U.S Patent No. 5 418 091 (23 May, 1995); A.S.Gozdz, C.N. Schmutz and J.M.Tarascon, U.S Patent No. 5 296 318 (March 22, 1994).Google Scholar
5. Kejha, J. B., U.S. Patent No. 5 705 084 (6 January 1998).Google Scholar