Batteries Using Thin-Film and Nanotechnologies

TF batteries were first designed and developed by the Oak Ridge National Laboratory (ORNL). TF batteries can be fabricated by direct deposition onto thin plastic sheet or chips. Unlike conventional batteries, TF batteries offer maximum bending capability when fabricated on a thin plastic and can be shaped into whatever form-factor needed by a particular application. These TF batteries also scale nicely in terms of size and geometric shape. Operational tests conducted by various users reveal that these batteries exhibit no deterioration in performance when operated over a wide temperature range from -30°C and +140°C. Furthermore, the battery performance remains unaffected by a heating temperature of 280°C under automated solder-refiow. 

This current limitation is the most serious drawback of flexible TF batteries. Therefore, to achieve high current densities, it is necessary to heat-treat the cathode at temperatures higher than 700°C. This shortcoming tends to prevent the use of flexible polymer substrates for cathode films in some specific applications. The internal resistance of such batteries is dependent on the polyimide sheet thickness and the annealing temperature, which must not exceed 400 C. If the battery is made on a rigid ceramic substrate with a cathode of comparable thickness, annealing temperatures as high as 750°C can be used. 

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