Polymers for electrochemical devices (original) (raw)

Polymeric materials are already present in electrochemical storage devices such as batteries and PEM fuel cells. The polymer is an electro-active material in lithium p)lymer batteries. Scvcnl nctuork bascd polymer elcctrolqtes providc thermal. mechanical and redos stabilities. while insuring a high conductivity level. Linear unsaturated polyether precursors may be obtained either by step-growth polymerization from oligomcric polyethers, or by ring-opening polymerization from oxinne mixturcs. Some prototype pcrformanccs. performed o n a 1 0 Wh lithium polymer cell, arc presented and discusscd. This paper concerns thc uses of polymeric materials in clcctnrhcmical dci'iccs such a$ battcrics, elcclrwhromic displa) s o r scnsors. 'I'hcrc is indccd n growing intcrcht in high cncrg) storage dcviccsmd cxtcn\ivc basic and applicd rcscarch has h.cn carried out this last decade to satisf) lhc demand for portable elcclronics i.e vidco-camera, computer, portahlc tclcphonc and so o n .-\s a rcsult of cnrironmental concern. connected with thcrnial vchicle pollution. urhiln electrical cars have appcarcd as one of the solutions to dccrcasc the atmospheric pollution. In both cascs. i.c portable electronic and clcctrical cws. high spccific cncrgy and high cncrey dcnsit) arc rcquircd for the batteries. More specially, lifetime and cost per k\Vh appear as kcy parameters for thc selcction of elcctrical car batteries 5% hich must provide sufficient autonomy for urban rehiclcs. while hybrid solutions, involving in particular fucl cells, arc sought for inter-urban uses. BATTERIES : STATE OF n i E x r Among the commercially available battcrics, only Lead acid and Nickel Cadmium batteries are proposed in large capacities. But, despite improvements. the specific energy of commercial Lead acid batteries hardly reaches 35 Whikg, while that of NickcliCadmium ranges from only between 45 and 50 Whikg.