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We found that the Na/Cl battery decay was due to the Na anode and not the cathode, based on that a battery using fresh Na, fresh electrolyte and a recycled aCNS electrode from a decayed battery could cycle stably again with normal charge – discharge behavior. The uoride containing additives, known to facilitate the formation of robust solid electrolyte interphase (SEI) on alkaline metal battery anodes in general, were found important to prolong the cycle life of our Na/Cl battery29-33. Batteries with no additive showed the worst cycle life (< 50 cycles). When only 2 wt% NaFSI was added, the cycle life of the battery improved to about 70 cycles, and when a mixture of 2 wt% NaFSI/NaTFSI was added, the battery showed the best cycling performance (> 100 cycles) (Fig. 4a). The composition on Na metal surface after immersion in electrolyte (4 M AlCl3 in SOCl2) with and without 2 wt% NaFSI/NaTFSI additives were analyzed by XPS. We found NaCl coating on Na metal due to reaction with SOCl2 in both samples, analogous to LiCl formed on Li in Li – SOCl2 primary batteries (Extended Data Fig. S6a, d)34-36. Abundant elements of F, N and S, assigned to NaF, Na2SO4, Na2S2O3, Na2SO3 were observed only on Na in the uoridecontainingelectrolyte,suggestingreactionsbetweenNaandanionsFSI-andTFSI- forminga more protective SEI layer on Na (Extended Data Fig. S6a, b, c)37-40. The uoride containing SEI was formed in the rst few cycles over which the coulombic e ciency gradually increased to ~ 100% (Fig. 3a). A more robust SEI layer could prevent or slow down reactions with corrosive species in the electrolyte including Cl2, SOCl2, SCl2 and SO2Cl2. When the battery eventually decayed, the overpotential increased accompanied by a drop in coulombic e ciency (Extended Data Fig. 6e). The impedance of the battery increased signi cantly as well, caused by the build-up of thick insulating NaCl on the Na anode. Our observation was consistent with previous results that the SEI on alkaline metal anode was more robust when both FSI- and TFSI- anions were present, leading to better sodium battery cycle lives1,41. Lastly, our amorphous carbon nanosphere was a novel positive electrode material for the Na/Cl battery owing to its ultra-high surface area (3000 – 3200 m2/g) and high porosity (2.76 cm3/g). We compared several widely used commercially available amorphous carbon including acetylene black (AB) and ketjenblack carbon black (KJ) to aCNS as positive electrode (Fig. 4b). The battery using AB as positive electrode could only run for less than 20 cycles and battery using KJ as positive electrode showed a better cycle life than AB but the coulombic e ciency was always lower than 90%. We attributed aCNS’s high cycling performance to both high surface area and porosity that were superior to AB. On the other hand, KJ showed higher pore volume but exhibited much lower surface area than aCNS (Extended Data Table 1). High surface area and porosity helped the positive electrode to better accommodate insoluble discharge product, i.e., NaCl in our battery42. In addition, carbon with high surface area and porosity could trap the corrosive species such as Cl2, SCl2, SO2Cl2 in the electrolyte better, reducing corrosion of the anode and improving battery’s cycle life. We employed the Na/Cl battery to light up of an LED light that required an operating voltage of 3.0 V – 3.2 V. The current measured through the LED was ~ 12.03 mA with a high current density of 4.57 mA/cm2 Na, equivalent to a discharge rate of 1563.35 mA/g (based on aCNS mass) (Fig. 4c). The new Page 7/20PDF Image | Rechargeable NaCl Battery Hongjie
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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 |