The present invention relates to a zinc/aqueous polysulfide rechargeable flow battery (100) made of a first half-cell (110) comprising a first electrolyte (114) containing a source of Zn.sup.2+ ions and a static (112) or flowable electrode disposed within the first half-cell, said first half-cell being connected in a closed-loop configuration through a first pump (116) to a first external tank (115) containing the first electrolyte; a second half-cell (120) comprising a second electrolyte (124) in which polysulfides are dissolved and a static (122) or flowable electrode disposed within the second half-cell, said second half-cell being connected in a closed-loop configuration through a second pump (126) to a second external tank (125) containing the second electrolyte; and a catalyst in the second half-cell, on the surface of a static electrode or dispersed in form of particles in the second electrolyte; and a separator (130) between the two half-cells.

The rechargeable flow battery of the invention avoids the use of toxic or environmentally harmful chemicals.

A single cell C includes a membrane electrode assembly M in which an electrolyte membrane 1 is interposed between a pair of electrode layers 2, 3, and a pair of separators 4 that form gas channels C between the pair of separators 4 and the membrane electrode assembly M, wherein the electrode layers 2, 3 include first gas diffusion layers 2B, 3B of a porous material disposed at the side facing the electrolyte membrane 1 and second gas diffusion layers 2C, 3C that are composed of a metal porous body having arrayed many holes K, and a part of the first gas diffusion layers 2B, 3B penetrates the holes K of the second gas diffusion layers 2C, 3C to form protrusions T. Accordingly, the surface of the electrode layers 2, 3 has a fine uneven structure. As a result, an improvement in liquid water discharging function and an improvement in power generating function were achieved at the same time.

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 μmol cm.sup.−2 day.sup.−1 (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.

Disclosed herein is a porous electrode substrate in which carbon fibers are dispersed in the structure thereof have a fiber diameter of 3-15 micron and a fiber length of 2-30 mm, and are bound to one another by carbonized resin such that, when a pore distribution in the porous electrode is determined with a mercury intrusion porosimeter, such that a pore distribution curve is plotted on a graph having a common logarithmic scale on the horizontal axis, and a 1-100 micron pore diameter range of the pore distribution curve includes 80 or more measurement points at equal intervals along the common logarithmic scale, the pore distribution has a skewness S of -2.0<S<-0.8 and a kurtosis K of 3.5<K<10 in the 1-100 micron pore diameter range.

Microbial fuel cells capable of generating energy from an organic-based fuel are described. The microbial fuel cells can include an anode component, a cathode component, and a separator component selected to reduce spacing between the anode and the cathode thereby improving performance of the microbial fuel cell. Cathode components including particular components that improve the lifetime, performance, and production of the cathode component at reduced cost also are described, as well as a method of using the microbial fuel cells.

Microbial fuel cells capable of generating energy from an organic-based fuel are described. The microbial fuel cells can include an anode component, a cathode component, and a separator component selected to reduce spacing between the anode and the cathode thereby improving performance of the microbial fuel cell. Cathode components including particular components that improve the lifetime, performance, and production of the cathode component at reduced cost also are described, as well as a method of using the microbial fuel cells.

Disclosed herein are ceramic selective membranes and methods of forming the ceramic selective membranes by forming a selective silica ceramic on a porous membrane substrate.

Disclosed herein are ceramic selective membranes and methods of forming the ceramic selective membranes by forming a selective silica ceramic on a porous membrane substrate.

A separator for at least one of electrochemical energy accumulators or converters includes: a porous substrate with a comb polymer, the comb polymer containing a polymer main chain along several lateral chains that are covalently bonded to the polymer main chain. At least one of the lateral chains has at least one Lewis-acid or Lewis-base functionality.

A separator for at least one of electrochemical energy accumulators or converters includes: a porous substrate with a comb polymer, the comb polymer containing a polymer main chain along several lateral chains that are covalently bonded to the polymer main chain. At least one of the lateral chains has at least one Lewis-acid or Lewis-base functionality.