New Types of Rechargeable Lithium and Lithium-ion Polymer Batteries a S.Panero, a L. Settimi, b F. Croce and a B. Scrosati a Dipartimento di Chimica, University of Rome “La Sapienza”, 00185 Rome, Italy b Dipartimento di Scienze del Farmaco, University of Chieti, 66013 Chieti, Italy The activities in progress in our laboratory for the development of new types of lithium batteries to be proposed for portable electronics and hybrid car application, are reviewed and discussed. The research has been mainly focused on the characterization of new electrode and electrolyte materials. Results related to improved, solvent-free , as well as gel-type, polymer electrolytes are particularly stressed. It is shown that the use of proper gel electrolytes in combination with suitable electrode couples, allows the development of new types of safe, reliable and low cost lithium ion batteries which appear very promising power sources for hybrid vehicles. Introduction Lithium ion batteries are the power sources of choice for portable electronics (1,2) and, accordingly, they are produced at a rate of several millions of units per year. However, there is still a need for further improvements in order to meet the demands of the continuously evolving sophistication of the portable devices. Thus, new lithium ion battery configurations assuring increase in capacity, in safety, in energy and in power density, as well as in compatibility with the environment, are urgently required. The progress and the sophistication of the portable electronics is not the sole reason which motivated the R&D of new types of rechargeable lithium batteries. Another driving force is the concern on the quality of the air in our planet, associated with the continuous and dramatic increase of the concentration of carbon dioxide. Thus, there is an urgent need to replace a large fraction of the gasoline cars with zero emission, electric vehicles, EVs or, at least with controlled emission, hybrid vehicles, HEVs. The HEVs presently on the road mainly use a nickel-metal hydride battery as the energy storage unit. However, alternative types of batteries, having higher energy density and lower cost than Ni-MH, are urgently needed to improve car performance and market competitiveness. In principle, lithium ion batteries can do the job, however only if new configurations assuring high rates, combined with safety and low cost, are identified. Accordingly, intensive research activity is presently carried out to develop lithium batteries having these properties. One approach has been that of passing from liquid- electrolyte-based configurations to polymer-structures. Indeed, the latter have several specific advantages which includes: i) simplicity of manufacture; ii) wide variety of shapes and sizes; iii) high energy density; iv) high safety ; v) remote chances of internal shorting. Obviously, in this technology the crucial component is the polymer electrolyte, which must have properties comparable to those of the replaced liquid solution. Our laboratory has been involved in lithium polymer electrolyte R&D for many years. Basically, this activity has been focused on two types of polymer electrolytes, namely: i) the solvent-free membranes, formed by blending poly(ethylene oxide), PEO, with a lithium salt, LiX and ii)the gel-type membranes, formed by trapping liquid ECS Transactions, 1 (26) 1-7 (2006) 10.1149/1.2209351, copyright The Electrochemical Society 1 ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 117.169.1.28 Downloaded on 2014-10-13 to IP