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details are presented in Supplementary Section 9) support our assignment of the spectral changes to polaron and bipolaron formation, as does a prior report of polythiophene spectroelectrochemistry.33 Importantly, the spectral evolution suggests complete conversion of neutral polymers into the charged state, indicating that the full volume of the electrode undergoes charging. Scanning to more positive potential shows that higher levels of charging can be achieved, although this compromises the coulombic efficiency of the electrode (Supplementary Section 10). For the n-type polymer the spectroelectrochemical data suggest reduction of the polymer chains resulting in the formation of an electron polaron at a potential of -0.4 V and bipolaron between -0.4 V and -0.75 V vs Ag/AgCl. Both these processes are reversible over multiple cycles. Our assignment of the spectral features to polaron and bipolaron formation are again supported by calculated absorbance spectra (normalized) of neutral and charged monomers (Figure 2f). Cyclic voltammetry measurements on p-type and n-type polymer films of different thicknesses at a fixed scan rate (50 mV s-1) allowed us to estimate the specific capacity of the films at 25 mAh cm-3 for the p(gT2) and 36 mAh cm-3 for the p(ZI-NDI-gT2) polymers; these represent charge loadings of around 0.6 holes per alkoxybithiophene repeat unit (gT2) and 1.4 electrons per ZI-NDI-gT2 repeat unit, which approach the theoretical limit of these materials (see Supplementary Section 11 and 12). Continuous cycling showed that 70% of the initial (2nd scan) capacity is retained after 1000 cycles in water for both polymers (Supplementary Section 13). Water based polymer battery The encouraging specific capacity, charging rate and stability of the n- and p-type polymer electrodes suggests that they may perform well in a two-electrode battery structure. We construct such an electrochemical charging device using the n-type p(ZI-NDI-gT2) polymer film characterized in Figure 2b and d and a p-type p(gT2) film with similar capacity as anode and cathode in an electrochemical cell filled with a salt-water (0.1M NaCl:DIW) electrolyte. The expected operation of the device is illustrated in Figure 3a. At equilibrium, the electrochemical potential of anode, electrolyte and cathode is constant across the device (black dashed line in Figure 3c). Note that the precise value of this potential depends on the state of charge of each electrode and may vary over lifetime due to imbalanced charge retention performance in the two electrodes (see discussion below). When a positive potential Vbattery is applied to the cathode with respect to the anode, Na+ ions are attracted to the anode where, as we discuss below, they become electrostatically bound to the negatively charged polymer while Cl- ions are attracted to the cathode and bind to the positively charged p-type polymer. The absolute values of the half-cell potentials Vn and Vp (where Vbattery = Vp-Vn) are not known but their values should not extend beyond the potentials for reduction and oxidation of water (indicated in Figure 3b) for stable operation in water. The measured CV response of the two-electrode device encloses a large area, which is consistent with the CVs of the individual electrodes as illustrated in Figure 3c. The device can be operated at an applied potential of 1.4 V which is the sum of potential ranges used to characterize the p-type (0.5 V vs Ag/AgCl) and n-type (-0.9 V vs Ag/AgCl) polymers. Figure 4a and 4c show the spectroelectrochemical characterization of the polymer battery for a cyclic voltammetry measurement run at 100 mV s-1 (black line in Figure 4a). The spectroelectrochemical response for the two-electrode device (Figure 4c) shows, by comparison with individual electrode spectra, that electrochemical charging of the battery device produces the bipolaron in both films. Notably, integration of the reversible current from the CV data in Figure 4a shows that 78% to 94% (depending on rate of discharge) of the total maximum stored charge can be extracted at positive voltages, while galvanostatic measurements suggest that 4PDF Image | salt water battery with high stability
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Product and Development Focus for Infinity Turbine
ORC Waste Heat Turbine and ORC System Build Plans: All turbine plans are $10,000 each. This allows you to build a system and then consider licensing for production after you have completed and tested a unit.Redox Flow Battery Technology: With the advent of the new USA tax credits for producing and selling batteries ($35/kW) we are focussing on a simple flow battery using shipping containers as the modular electrolyte storage units with tax credits up to $140,000 per system. Our main focus is on the salt battery. This battery can be used for both thermal and electrical storage applications. We call it the Cogeneration Battery or Cogen Battery. One project is converting salt (brine) based water conditioners to simultaneously produce power. In addition, there are many opportunities to extract Lithium from brine (salt lakes, groundwater, and producer water).Salt water or brine are huge sources for lithium. Most of the worlds lithium is acquired from a brine source. It's even in seawater in a low concentration. Brine is also a byproduct of huge powerplants, which can now use that as an electrolyte and a huge flow battery (which allows storage at the source).We welcome any business and equipment inquiries, as well as licensing our turbines for manufacturing.| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |