resistivity of 85 ohm cm and the maximum formation voltage for tantalum foil at 25 u00b0 c was 145 v a set of 6 aluminum electrolytic capacitors was constructed using the following electrolyte formulation 20 g n ethylpiperidinium diethylphosphate et 3 po 4 piperidine 120 g 4 butyrolactone and 3 g h 2 o the capacitors were of 250 v rating and made with etched and formed aluminum anode foil life test data at 200 vdc and 125 u00b0 c capacitance in u03bcf dissipation factor and leakage current in u03bca at 0 hr and 2000 hr are presented in table iii table iii______________________________________ 0 hrs 2000 hrs capacitor u03bcf df u03bca u03bcf df u03bca______________________________________1 12 44 3 91 3 8 12 20 4 19 1 92 11 96 3 88 3 4 11 65 4 79 2 63 11 88 4 07 2 9 11 61 3 99 1 64 12 25 3 81 6 4 11 97 4 34 1 95 12 01 3 50 3 8 11 73 3 64 2 06 11 61 3 98 4 9 11 31 3 84 1 6average 12 02 3 86 4 2 11 74 4 13 1 9______________________________________ it is seen that capacitance and dissipation factor remained virtually unchanged or changed only slightly and leakage current improved temperature stability average of the six units is presented below table iv______________________________________temperature u03bcf df impedance u03c9 impedance ratio______________________________________125 u00b0 c 13 14 2 56 101 0 9625 u00b0 c 12 59 4 22 105 1 0.