Physical Diffusion and Electron-transfer Dynamics of Electroactive Solutes in Polymer Electrolytes Ⅲ. Effect of the Polymer Solvents

The diffusion coefficients(Dapp) and the heterogeneous electron transfer rate constants(ks)for ferrocene in several polymer solvents were determined by using steady-stae voltammetry. Thetemperature dependence of the two parameters indicates Arrhenius behavior. The polymer solventeffects on diffusion and electron transfer dynamics of ferrocene were discussed

Physical Diffusion and Electron-transfer Dynamics of Electroactive Solutes in Polymer Electrolytes Ⅰ. Effect of the Nature of Electroactive Solutes

The diffusion coefficients(Dapp) and the heterogeneous electron-transfer rate constants(ks)for ferrocene and its seven derivatives in MPEG/LiClO4 electrolyte were determined by using steadystate voltammetry. The two parameters increase with increasing temperature, indicating Arrhenius behavior. The effects of the nature of electroactive solute molecules on Dapp, ks, and the half-wave potentials(E1/2) are discussed.

Physical Diffusion and Electron-transfer Dynamics of Electroactive Solutes in Polymer Electrolytes Ⅱ. Effect of the Ionic Size of Supporting Electrolytes

The ditheion coefficients(Dapp) and the heterogeneous electron-transfer rate constan(ks)for ferrocene in MPEG/salt electrolytes were determined by using Steady-stae voltammetry. The temperature dependence of the two parameters obeys the Arrhenius equstion. The effect of the ionic size of sir supporting electrolytes on diffusion and electron transfer dynamics of fermcene was discussed

THE CONDUCTIVITY BEHAVIOR OF A POLYMER GEL ELECTROLYTE

A new kind of polymer gel electrolyte which is composed of polytriethylene glycol dimethacrylate(PTREGD), propylene carbonate(PC) and LiPF6 has been prepared by thermal polymerization. The conductivity was measured as a function of temperature, and it was found that the Arrhenius equation was held very well through out the salt concentration studied. Maximum room temperature conductivity of 4.95 x 10(-4) S/cm, as well as a minimum activation energy value of 18.90 kJ/mol were obtained at the same salt concentration of 0.22 mol/L.

STUDY ON A NEW COMB POLYMER ELECTROLYTE(Ⅱ)

s: A comb polymer(CP350) with oligo-oxyethlene side chains was prepared from methyl vinyl ether/maleic anhydride copolymer. Homogeneous amorphous polymer electrolyte were made from the comb polymer and LiCF3SO3 by solvent casting from acetone, and their conductivities were measured as a function of temperature and salt concentration. Maximum conductivity close to 5.08×10-5S/cm was achieved at room temperature at [Li]/[EO] ratio of about 0. 12.

STUDY ON A NEW COMB POLYMER ELECTROLYTE(Ⅲ)

A new solid polymer electrolyte has been prepared using NaClo4 and a comb-branch polymer with oligo(ethylene oxide ) side chains.The thermal and ionic conductive roperties of the electrolytes were investigated The profile of conductivity at various temperatures follows the VTF plots SOlid twiner ￣(SPE) have reeved aonallerable a￣the because af thedPatental &Pplica￣ in ￣-state batteries and ￣romic deviate l.The realizablethat high condutheity in twiner ￣the is dependent on ￣ overman m￣ afpolymer Segments led to the eXPlorathe of comb payment as h￣ for POlymer￣yte formadri. The general ￣Cept is to u￣ a ￣ie backbone and attach tothis shortrohch POlar oligomers Capable af complexing scall mud ￣. Since the shortaide chains do nat ￣ in the absence and p￣ of scall mud ￣, theresulbog polymer el￣ythe win b￣e amorphous- We have prepared a combPOlymer(cP35e) based on mdsyl veal acer/m￣ anhydride copolymer baCkbonet21.Thefracture ed cP35e is as fdriws:NaCIO. Nas purchased from Bailing Nanshangle Chemnd F￣ and dried in vacuum at149oC far 24hr. The ￣ymer ￣ Here prepared by mixing CP356/￣e withNaCIO./acetone in a argon-f￣ gable bax. The eduthes were cab on PTFE dishes, andthe ￣ents were aamed to evaporate at ￣m temperature uns the SOlu￣ did notffew and were aomp￣y removed in vacuo at 80to- At hat, free-shading SPE films couldbe Obeyyed. Thermal behaviours were bodied with a PEAKs--ELMER DSC-7 deferentialscanning claim￣ at a headsg rate of 2dOC/min over the temperature range af-7B-135ie. The gab iran￣ temperature Nas taken as the midPOint temperature of thebaseline shin observed during tr￣. The trim conduchvity was measured asd￣ed prevboaly['l. No enddriermic and ￣ermin peaks appeared at the DSCthermograms. This implieS that the cP35e/Nalllo. complexeS are funy amorphous. Thed6Pendence ed T. value on the ratify af [taJ/[EOI are shorn in Fig.1. The T. rmonotonicthe with the tea]/[EOI race because af the inter￣ between barium ions and￣ acer OXYgen atoms. The inter￣n suppressed the wemental m￣ of sidechains, and this suppr￣ Hut race the T. af complexeS. The standard temperature T.ie taken as T.-seK and the VTF pad af cP35e/NalllO. complco Show ￣ntlinearity(Fig.2). It sugg￣ that the major ion transport ￣ pad in the amorphousregains. The ed concentration dependence of trite conduchvitieS of CP35e/NalllO. isacorn in Fig.3. The maximum bole ccnduchvity(1.93X10-'S/cm) is found near[ba]/[Eol-e.25. As the NalllO. concentration iner￣, the number of carrier ionsincreases, while the segmental m￣ af side chains d￣￣: thus the mobility ofcarrier ions decreases. It is very inter￣g that chen [Na]/[EO] is 9.25, O/Na is 4/1,420Nthe the PKO af high moleCUlar aught then ￣ates with mAn ho with the [OI/tMIrace of 4/1. This indic￣ that IM]/[EOI-1/4 may be the OPossum race of ￣iner￣ complexeS. we try to Study the thermal stabal' of CP35e/Nac1O.an pace ([ ba ] / t EO 1 = 1:4. 5 ) 'sin g tern Perattir￣anging iR tech blue w iap a headsg rate ofn/min. The iR sp￣a at various temperatures are shown in Fig.4. Two newPeaks(1859.5. 1781.2cm--' ) appear at 140OC. TheY are the char￣ ah￣ban￣ ofm￣ anhydride ring. This implieS that the ￣ in CP358 might d￣p￣ at 148ro andreproduce the m￣ anhydride ring. So the upper -tim it-tern feature af the CP 3 5 0 / N aCIO.comples as prangal 'l￣Yte materall might be 149oC.[gal/tEO] Fig.1 Sail concentrated dependenceof glass iran￣ temperatureFig.z LOg(6 T'/') ye￣s 19ee/(T-T.)[gal/[EO]-e.e3(o ),9.19(7 ),e.Ze(O)'e.32. )Fig.3 Salt concentration dependenceof ionic conduchvityFig.4 IR sp￣a at varioustemperatures for CP359/Naq1O.([Na]/ [cO 1=1:4.5 )