We present studies of the photodoping process in underdoped metallic YBa2Cu3Ox, where x≈6.6. Measurements of the time-dependent electrical resistivity during photoexcitation were performed at several temperatures and with two different lasers as the light source. The effect of photodoping on the samples was characterized by the resistivity reduction ΔR(N)/R(0) and by the enhancement ΔTc of the superconducting transition temperature for a fixed photon dose of N = 1.2 × 1023 cm−2. At low temperatures, we observed a large ΔR(N)/R(0) but a small ΔTc. In the intermediate temperature range, both quantities were relatively small. At the highest studied temperature (270 K), ΔTc reached the largest values in these experiments, and ΔR(N)/R(0) was almost as large as at low temperatures. Interestingly, only at low temperatures did we observe a significant dependence of ΔR(N)/R(0) on the laser wavelength λ, whereas ΔTc is essentially independent of λ. The time dependence of the resistivity during the photoexcitation showed a stretched-exponential decrease at all temperatures, with values of the dispersion parameter β between 0.3 and 0.55, which are distinctly smaller than observed in persistent photoconductivity relaxation in YBa2Cu3Ox. β was essentially the same for the two laser wavelengths and showed only a weak temperature dependence. We observed a tendency of β towards smaller values (≈0.4) at low temperatures and to slightly higher values (≈0.5) above approximately 200 K. We interpret this finding within a microscopic theory of the stretched-exponential parameters, and conclude that there is a long-range interaction between the photoexcited electrons and the chain defects, which act as trapping centres and that the traps become mobile at high temperatures.

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Infinite Power Solutions manufactures a flexible rechargeable micro ampere-hour solidstate battery based on thin-film Lithium technology where the battery can be engineered into the product for life as a cost effective solution with “the battery that never needs to be replaced”. The performance characteristics of the battery combined with low power electronic textile applications will require “A Different Way of Thinking About Batteries” relative to battery management and innovative methods of recharging the battery (such as charging the battery whenever the materials are washed and dryed). This paper will review the characteristics of the battery specifically in relation to power generation for flexible electronic materials and the integration issues for a thin-film battery for flexible electronic materials.

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Automobile engine starting requires extremely high current, in the range of 600 Amps peak for 250 mS, then a 150 A to 300A sine wave at a reasonably stable voltage for 0.5 to 3 seconds. Stater efficiency increases with higher deliverable voltage. Batteries required for these applications should be capable of operation at temperatures ranging from -208 C to 508 C. Today, most automobiles are equipped with 40 to 60 pound lead acid batteries for engine starting. However. at unscheduled intervals, batteries fail due to battery life, neglect, or negligence (failure to switch off headlights, radio, compact disc players, etc.) These situatioas can place the operator of an automobile in a difficult situation, usually requiring assistance; another vehicle for ajumpstart, or a towing service provider. The practice of keeping an extra battery in most of these vehicles has been virtually nonexistent due to previously available battery size and weight.BQLBHZ Technologies Corporation (BOLDER) has developed a light weight emergency starting unit of less than 5 pounds based on heir patented TMF technology which is capable of starting many automotive engines. Currently marketed as SecureStartTM, available in Sears and Neiman Marcus stores, is capable of starting cars, small trucks, motorcycles, motorboats, generators, snowmobiles, and aircraft.The purpose of this paper is to present current, voltage and power delivery characteristics of a 12 V TMF battery. Also included are the repetitive putse-power characteristics at 600 and IOOOA, and a battery design developed by ATP using BOLDER TMF celIs.