Massachusetts Institute of Technology

Xinwei Chen

Yet-Ming Chiang

Alexander H Slocum, Jr

Kripa K Varanasi

Brian Richmond Solomon

W Craig Carter

Ahmed Helal

Zheng Li

Brandon James Hopkins

Kyle C Smith

Frank Yongzhen Fan

Jiayan Luo

Embodiments described herein relate generally to lithium sulfur batteries and methods of producing the same. As described herein, preventing coarsening of sulfur during the well-known melt-diffusion processing of cathodes allows a high areal capacity of 10.7 mAh/cmat current density of 3.4 mA/cm(C-rate of 1/5 h). The addition of a lithium salt, such as LiTFSI, prior to melt-diffusion can prevent coarsening of molten sulfur and allows creation of a sulfur electrode with a high concentration of triple-phase junctions for electrochemical reaction. In some embodiments, approximately 60-70% utilization of the theoretical capacity of sulfur is reached at a high loading (e.g., greater than 7.5 mg S/cm). The electrodes are prepared in lean-electrolyte environment of 3 ml/g(&#x2dc;70 vol % of electrolyte in the electrode) for high areal capacity in Li&#x2014;S batteries.

Systems and methods of preparing lithium sulfur electrode using sacrificial template

The flow cell includes first and second reservoirs having a selected volume containing a flowable redox electrode. A membrane separates charged and discharged material. An energy-extraction region includes electronically conductive porous current collectors through or adjacent to which the flowable redox electrodes flow and to which charge transfer occurs. Structure is provided for altering orientation of the flow cell whereby gravity induces flow of the flowable redox electrode between the first and second reservoirs to deliver power. By varying the angle of the cell, flow rate and power delivered on discharge or the charge rate on charge may be varied.

Gravity induced flow cell

In certain embodiments, the invention relates to an electrochemical device having a liquid lubricant impregnated surface. At least a portion of the interior surface of the electrochemical device includes a portion that includes a plurality of solid features disposed therein. The plurality of solid features define a plurality of regions therebetween. A lubricant is disposed in the plurality of regions which retain the liquid lubricant in the plurality of regions during operation of the device. An electroactive phase comes in contact with at least the portion of the interior surface. The liquid lubricant impregnated surface introduces a slip at the surface when the electroactive phase flows along the surface. The electroactive phase may be a yield stress fluid.

Lubricant-impregnated surfaces for electrochemical applications, and devices and systems using same

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Cambridge, MA, United States of America

Xinwei Chen