University of California

Sepion Technologies, Inc.

Massachusetts Institute of Technology

University of Illinois

Peter David Frischmann

Brett Anthony Helms

Sean Emerson Doris

Ashleigh L Ward

Jon-Michael Alessandro

Changyi Li

Yet-Ming Chiang

Jeffrey S Moore

Elton J Cairns

Nagarjuna Gavvalapalli

Frank Yongzhen Fan

Laura C H Gerber

Yoon Hwa

Provided are electrochemical cells including separators permeable to some materials and impermeable to other materials in electrolytes. Also provide are methods of forming such separators. The selective permeability of a separator is achieved by its specific pore diameter and a narrow distribution of this diameter. Specifically, a species responsible for ion transport in an electrochemical cell are allowed to pass through the separator, while another species is blocked thereby preventing degradation of the cell. For example, a species containing lithium ions is allowed to pass in rechargeable cells, while one or more species containing transition metals are blocked. In some embodiments, a separator may include a membrane layer with at least 90% of pores of this having a diameter of between about 0.1 nanometers and 1.0 nanometer. The membrane layer may be a standalone layer or supported by a membrane support.

Electrochemical cells with ionic sequestration provided by porous separators

A composite membrane with nanostructured inorganic and organic phases is applied as an ion-selective layer to prove processability, prevent dendrite shorting, and increase power output of lithium-metal anodes through better Li-ion conductivity. Nanoconfinement, as opposed to macroscale confinement, is known to dramatically alter the properties of bulk materials. Control over a ceramic's size, shape, and properties is achieved with polymer templates. This is a new composition of matter and unique approach to composite membrane design.

Microstructured ion-conducting composites and uses thereof

Intermittent energy sources, including solar and wind, require scalable, low-cost, multi-hour energy storage solutions to be effectively incorporated into the grid. Redox-flow batteries offer a solution, but suffer from rapid capacity fade and low Coulombic efficiency due to the high permeability of redox-active species across the battery's membrane. Here we show that active-species crossover can be arrested by scaling the membrane's pore size to molecular dimensions and in turn increasing the size of the active material to be above the membrane's pore-size exclusion limit. When oligomeric redox-active organic molecules were paired with microporous polymer membranes, the rate of active-material crossover was either completely blocked or slowed more than 9,000-fold compared to traditional separators at minimal cost to ionic conductivity. In the case of the latter, this corresponds to an absolute rate of ROM crossover of less than 3 &#x3bc;mol cmday(for a 1.0 M concentration gradient), which exceeds performance targets recently set forth by the battery industry. This strategy was generalizable to both high and low-potential ROMs in a variety of electrolytes, highlighting the importance of macromolecular design in implementing next-generation redox-flow batteries.

Redox-flow batteries employing oligomeric organic active materials and size-selective microporous polymer membranes

Polymers of intrinsic microporosity are provided herein. Disclosed polymers of intrinsic microporosity include modified polymers of intrinsic microporosity that include negatively charged sites or crosslinking between monomer units. Systems making use of polymers of intrinsic microporosity and modified polymers of intrinsic microporosity are also described, such as electrochemical cells and ion separation systems. Methods for making and using polymers of intrinsic microporosity and modified polymers of intrinsic microporosity are also disclosed.

Polymeric materials for electrochemical cells and ion separation processes

Metal-sulfur energy storage devices also comprising new redox mediator compounds are described.

Redox mediators for metal-sulfur batteries

To address the need for multi-functional binders specifically tailored for sulfur cathodes &#x3c0;-stacked perylene bisimide (PBI) molecules are repurposed as redox-active supramolecular binders in sulfur cathodes for Li&#x2014;S cells. In operando lithiation of PBI binders permanently reduces Li&#x2014;S cell impedance enabling high-rate cycling, a critical step toward unlocking the full potential of Li&#x2014;S batteries.

Growing community of inventors

Berkeley, CA, United States of America

Peter David Frischmann