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this value is over 90% for the range of C-rate considered here. These results indicate that the device effectively implements the function of energy storage. The battery device exhibits a specific capacity above 15 mAh cm-3 at C-rates >1000. Note that because the battery’s specific capacity accounts for both electrodes it is about half the value for the individual polymers. The fast charging/discharging capability is confirmed by the relative insensitivity of the CV to scan rate up to 200 mV s-1 and the linear dependence of peak current on scan rate up to 2000 mV s-1 (Supplementary Section 14). The peak shift in the cyclic voltammograms and the drop in capacity at fast scan or charging rate (Figure 4b) are consistent with the presence of a series resistance due to the two FTO layers in the order of 100Ω. Further evidence that response is rate limited by series resistance and internal charge-transfer resistance is provided (Supplementary Sections 15-17). Finally a stability measurement, displayed in Figure 4d, was run on the cell, showing less than 20% drop in capacity over 1000 cycles. On the mechanism of polymer charging and discharging The polymer thin films investigated in this work can be efficiently charged and discharged at fast rates. We attribute the high rate capability of these electrodes to the structure of the polymer side chains which is suitable for the transport of ions within the film. We found that glycol side chains are a favorable medium for the transport of chloride ions in the case of the p(gT2) polymer. We assign this to the limited ability of the glycol chains to interact with anions. Oxygen atoms in this structure have a strong tendency to chelate positive ions.34,35,26 Carbon atoms on the other hand, despite being polarized, are not able to chelate negative ions due to the unavailability of unpaired electrons (sp3 hybridization) and as a result they enable and do not restrict the transport of anions. For example, fast switching times can be observed when polymer semiconductors including glycol side chains are operated in organic electrochemical transistors (OECTs) where anions need to migrate into the bulk of the polymer.27,28 Regarding the (zwitterion) p(ZI-NDI-gT2) polymer, DFT calculations (see Supplementary Section 9 for full discussion) show that injected negative charges are expected to localize on the NDI unit, which suggests that the side chain on that unit could help to control electronic-ionic charge interactions. We hypothesize that cations do not need to migrate close to the backbone of p(ZI-NDI-gT2) upon charging of the electrode due to the presence of a permanent positive charge on the ammonium group close to the NDI unit. When the polymer is in its neutral state, the positive charge on the ammonium group is compensated by the carboxylate ion of the zwitterion side chain. When the polymer is reduced, the ammonium ion can compensate the negative charge on the backbone, which we expect to localize on the NDI unit, leaving the negative carboxylate group uncompensated. This would encourage sodium ions to interact with the carboxylate group of the zwitterion side chain rather than to approach the polymer backbone, facilitating the attachment and release of ions upon charging. A schematic of the proposed mechanism is shown in Figure 1c. In order to explore this hypothesis we synthesized and characterized another n-type polymer, p(g7NDI-gT2), where glycolated chains are attached to the NDI unit instead of the zwitterion chain. Glycol chains allow penetration of sodium ions into the polymer film but may be expected to inhibit cation transport due to the chelation by oxygen atoms.36 Accordingly, we observed an upper limit to reversible charging of p(g7NDI-gT2) when scanning to potentials beyond the first reduction peak. A similar behavior was also reported previously for OECTs using polymers with glycol chains.25 We tentatively assign the larger reversible specific capacity of the (zwitterion) p(ZI-NDI-gT2) polymer, compared with the case of the (glycolated) p(g7NDI-gT2) polymer, to the different nature of the interaction between sodium ions and electron polarons which appears to allow the bipolaron to form. The characterization of the p(g7NDI-gT2) polymer is presented in Supplementary Section 18. 5PDF 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 (Standard Web Page)