PDF Publication Title:
Text from PDF Page: 061
Johnson – NETL, Wang – PSU III.B.6 Development of High-Energy Lithium Sulfur Cells polysulfides – intermediate charge/discharge states of the cathode – are highly soluble in traditional electrolytes and can move throughout the battery, experiencing redox reactions and thus causing poor efficiency and loss of active material. Additionally, the lithium metal commonly used as the anode is vulnerable to mossy lithium and dendrite growth and cannot generally form a stable SEI layer, causing further capacity loss and safety concerns. These, combined with optimization and thermal safety considerations, necessitate a significant body of work to bring the Li-S to the commercialization stage. Approach To design a superior lithium-sulfur battery, we will focus on several aspects of cathode, anode, electrolyte, and whole-cell study and design. On the cathode side, we aim to increase the sulfur loading, optimize the carbon framework’s geometry and ability to adsorb lithium polysulfides, and enhance its practical usability and each-of-production. On the anode side, our work focuses on designing and optimizing lithium powder- and silicon-based composite anodes and determining the mechanisms behind their function. Electrolyte-wise, we are working to design new systems that improve SEI stability, decrease active material loss, increase active material utilization, and ensure battery safety. Additionally, we also seek to optimize battery fabrication parameters, ensure compatibility between all battery elements, and characterize the thermal safety and abuse tolerance of our Li-S system. Results Cathode. PSU-3 cathode material production has been scaled up to the 0.5 kg level, thanks to the development of a specially-designed large- capacity reactor system, with 100 g of materials shown in Figure III - 68 for scale. This has created a constant flow of material for use in full cell testing and pouch cell development. Material properties have been standardized and performance is consistent from batch to batch. Scale-up of PSU-4 and PSU-6 high-rate, high- loading cathode materials is still being investigated for the final phase of the project. PSU-3 cathode fabrication has also been optimized so as to allow for making high- loading, double-sided electrodes, thereby increasing cell level energy density by decreasing the mass of the current collector in the cell. In addition, rate and cycling performance of the PSU-3 and PSU-4 cathode materials have been investigated. PSU-3 cathodes with an active material loading of 5 mg S/cm2 can maintain a capacity of over 500 mAh/g even at 1C rate, and cycling performance was also tested and found to be excellent within 50 cycles. PSU-4 cathodes showed a stable capacity of over 700 mAh/g at a C/3 rate. Figure III - 68: 100 g of PSU-3 sulfur cathode material, synthesized via a new large-scale reactor approach Anode. Lithium powder/graphite (LiG) anodes have been tested in both full and half cells with various electrolytes. It was found that these anodes provided excellent half-cell stability (little capacity loss for 200 cycles at 0.5C rate) and a true capacity of over 1,000 mAh/g of electrode. However, full cell tests showed only modest performance (up to 400 mAh/g S, depending on choice of electrolyte). Another novel lithium-powder-based anode material, dubbed LiP, was also tested and showed much stronger full-cell performance. Coin cell full-cell tests showed capacities of around 600 mAh/g S after 100 cycles. The N/P ratio and pressing of these anodes were also studied. It was found that pressed electrodes had superior performance to unpressed electrodes, possibly because excess porosity in the unpressed electrodes enabling easier polysulfide diffusion and a stronger shuttle effect. In addition, scanning electron microscopy (SEM) imaging of LiP anodes after cycling shows that they maintain their overall structure better than lithium foil anodes, which is good for long term cell stability. Electrolyte. Several electrolyte systems have been tested this past year. Both PSU-E-1 and ANL-E-3 electrolytes showed promising performance, allowing for high-capacity stable cycling of sulfur cathodes. However, cells with PSU-E-1 electrolyte and high- loading cathodes were found to be quite sensitive to minor temperature fluctuations, while ANL-E-3 electrolyte was found to not perform well with high sulfur contents. To overcome these limitations, new electrolytes were developed. The new PSU-E-5 electrolyte was aimed specifically at high-sulfur-loading cathodes. This electrolyte was found to allow for stable cycling of cathodes with ~5 mg S/cm2 with a capacity of around FY 2013 Annual Progress Report 83 Energy Storage R&DPDF Image | Advanced Battery Development
PDF Search Title:
Advanced Battery DevelopmentOriginal File Name Searched:
APR13_Energy_Storage_d_III_Adv_Battery_Dev_0.pdfDIY PDF Search: Google It | Yahoo | Bing
Turbine and System Plans CAD CAM: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. More Info
Waste Heat Power Technology: Organic Rankine Cycle uses waste heat to make electricity, shaft horsepower and cooling. More Info
All Turbine and System Products: Infinity Turbine ORD systems, turbine generator sets, build plans and more to use your waste heat from 30C to 100C. More Info
CO2 Phase Change Demonstrator: CO2 goes supercritical at 30 C. This is a experimental platform which you can use to demonstrate phase change with low heat. Includes integration area for small CO2 turbine, static generator, and more. This can also be used for a GTL Gas to Liquids experimental platform. More Info
Introducing the Infinity Turbine Products Infinity Turbine develops and builds systems for making power from waste heat. It also is working on innovative strategies for storing, making, and deploying energy. More Info
Need Strategy? Use our Consulting and analyst services Infinity Turbine LLC is pleased to announce its consulting and analyst services. We have worked in the renewable energy industry as a researcher, developing sales and markets, along with may inventions and innovations. More Info
Made in USA with Global Energy Millennial Web Engine These pages were made with the Global Energy Web PDF Engine using Filemaker (Claris) software.
Sand Battery Sand and Paraffin for TES Thermo Energy Storage More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |