PDF Publication Title:
Text from PDF Page: 002
Journal of Materials Chemistry A PAPER Cite this: J. Mater. Chem. A, 2016, 4, 7207 Received 11th February 2016 Accepted 29th March 2016 DOI: 10.1039/c6ta01274d www.rsc.org/MaterialsA Introduction The harvest and storage of electrical energy from renewable sources have become increasingly important due to many reasons: the growing demand for electricity, a steady increase in oil price, fossil fuel depletion, and environmental consider- ations such as global warming from CO2 emission.1 Most green energy is harvested from natural sources such as wind, thermal, and solar power. Supplying electrical energy directly from these sources is difficult as the energy is still costly and not always available where and when it is needed.2 The development of large-scale, efficient electrical energy storage (EES) systems is highly desirable as it can help mitigate fossil-fuel related envi- ronmental issues and provide a solution to peak load in power supply by saving the energy during off-peak times and releasing it during on-peak times.3–5 Lithium-ion batteries (LIBs) combine high energy density (250–300 W h kg1), reasonable cost (250–400 $ kW h1), and long service lifetimes (2–10 years).4,6 However their wide appli- cation in portable electronic devices and electric vehicles may strain lithium production capability and increase their market price in the long term. Na-based batteries have gained much interest as candidates for post-LIBs. Not only is sodium abundant and low-cost, it also has a suitable electrochemical potential (E 1⁄4 2.71 V vs. the School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan 689-798, Republic of Korea. E-mail: ykim@unist.ac.kr; smhwang@unist.ac.kr †Electronic supplementary information (ESI) available. See DOI: 10.1039/c6ta01274d ‡ These authors contributed equally to this work. Saltwater as the energy source for low-cost, safe rechargeable batteries† Sangmin Park,‡ Baskar SenthilKumar,‡ Kyoungho Kim, Soo Min Hwang* and Youngsik Kim* The effective use of electricity from renewable sources requires large-scale stationary electrical energy storage (EES) systems with rechargeable high-energy-density, low-cost batteries. We report a rechargeable saltwater battery using NaCl (aq.) as the energy source (catholyte). The battery is operated by evolution/reduction reactions of gases (mostly O2, with possible Cl2) in saltwater at the cathode, along with reduction/oxidation reactions of Na/Na+ at the anode. The use of saltwater and the Na-metal-free anode enables high safety and low cost, as well as control of cell voltage and energy density by changing the salt concentration. The battery with a hard carbon anode and 5 M saltwater demonstrated excellent cycling stability with a high discharge capacity of 296 mA h ghard carbon1 and a coulombic efficiency of 98% over 50 cycles. Compared with other battery types, it offers greatly reduced energy cost and relatively low power cost when used in EES systems. standard hydrogen electrode, SHE).7–9 Na–air batteries have been studied intensively because their theoretical energy density (1100–2080 W h kg1) is high compared with that of existing LIBs.10–13 Aqueous Na–air batteries possess especially good reversibility owing to their soluble discharge product NaOH, compared to aprotic Na–air batteries whose discharge products are insoluble Na2O2 and/or NaO2.10,14–16 Nevertheless, the repeated plating and stripping of the Na metal anode during cycling would reduce this reversibility, impeding further development of aqueous Na–air batteries. It can also cause safety issues, due to its high reactivity with the electrolyte and resultant dendritic growth.9,17,18 Our group has recently developed a new ‘seawater battery’19–21 as a hybrid between a battery and a fuel cell. The seawater battery uses natural seawater containing Na+ as the catholyte, making its application in large-scale, stationary EES systems environmentally friendly and price-competitive. Anode materials such as hard carbon or other Na-insertion materials are also safer as they are free of Na metal.19 However, the use of seawater limits the EES plants to coastal locations. The amount of Na+ in seawater (approximately 0.46 M) also limits the battery energy density.22 In this work, we demonstrate an alternative ‘saltwater battery’, using the more available NaCl aqueous solution as the catholyte. This is distinct from existing saltwater batteries, where the saltwater only serves as an electrolyte between two galvanically coupled electrodes. Our saltwater battery could offer signicantly reduced production cost, which is one prerequisite for large-scale EES systems, together with the removal of the geographical limitation. The battery consisting of a hard carbon anode and 5 M saltwater catholyte showed This journal is © The Royal Society of Chemistry 2016 J. Mater. Chem. A, 2016, 4, 7207–7213 | 7207PDF Image | Saltwater as the energy source for low-cost batteries
PDF Search Title:
Saltwater as the energy source for low-cost batteriesOriginal File Name Searched:
A201647207-7213.pdfDIY PDF Search: Google It | Yahoo | Bing
Product and Development Focus for Salgenx
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 flow battery manufacturing.CONTACT TEL: 608-238-6001 Email: greg@salgenx.com (Standard Web Page)