Alkaline electrochemical cells are provided, wherein methods to decrease or eliminate shorting in batteries by preventing zinc oxide reaction precipitate from creating a conductive bridge between the two electrodes. The alkaline electrochemical cell comprising dissolved zinc oxide or zinc hydroxide in at least the electrolyte solution, and/or solid zinc oxide particles or zinc hydroxide in the anode, a silicon donor in the anode, and/or a bilayer separator optimally comprising a high-density layer and a low-density layer.

A method of making a free-standing nanoporous Zn is provided. The method includes compacting a predetermined amount of Zn compound precursor into a form of an anode; controlling a thickness of the Zn compound precursor to obtain desirable porosity; and reducing the Zn compound precursor in an electrochemical cell having an electrolyte at a predetermined volage against a reference electrode to obtain a nanoporous Zn anode. The nanoporous Zn includes continuous metal ligaments and pores each having a uniform width of around a few hundred nanometers. The nanoporous Zn may serve as an anode in a rechargeable Zn battery having the nanoporous Zn anode coupled to a conductive substrate, a physical block, an electrolyte, a reference electrode, and a cathode electrode, to deliver a high areal capacity and a long cycle life.

A battery comprises an anode, a cathode, and a polymer electrolyte disposed between the anode and the cathode. The polymer electrolyte can include an inert hydrophilic polymer matrix impregnated with an aqueous electrolyte. The hydrophilic polymer matrix can include a polar vinyl monomer, an initiator, and a cross-linker. A gassing inhibitor can be included in the polymer electrolyte to help avoid issues with overcharging of the electrodes.

An alkaline electrochemical cell has a central cathode having a corresponding cathode current collector electrically connected with a positive terminal of the electrochemical cell. The cathode current collector has a tubular shape, such as a cylindrical shape or rectangular shape, extending parallel with the length of the central cathode. The cathode current collector is embedded within the central cathode, such as at a medial point of a radius of the central cathode, thereby minimizing the distance between the cathode current collector and any portion of the central cathode, thereby increasing the mechanical strength of the cathode and facilitating charge transfer to the cathode current collector.

A zinc-air battery cell assembly comprising: a cathode can that includes: a planar base, and an elongated cathode sidewall that extends to a terminal cathode sidewall end, and an anode can that includes: a planar top end, and an elongated anode sidewall that extends to a terminal anode sidewall end, the anode can disposed nested within the cathode can with the elongated anode sidewall disposed parallel and adjacent to the elongated cathode sidewall. The zinc-air battery assembly further includes a cavity defined by the cathode can and the anode can disposed nested within the cathode can, and a grommet that provides a seal between the cathode can and the anode can while also keeping the anode can and the cathode can separate.

Powders, electrodes, zinc-air batteries and corresponding methods are provided. Powders comprise perforated shells having a size of at least 100 nm and comprising openings smaller than 10 nm. The shells are electrically conductive and/or comprise an electrically conductive coating. Powders further comprise zinc and/or zinc oxide which resides at least partially within the shells. Methods comprise wetting the shells with a zinc solution to yield at least partial penetration of the zinc solution through the openings, and coating zinc internally in the shells by application of electric current to the shells. Upon electrode preparation from the powder, cell construction and cell operation, zinc is oxidized to provide energy and the shells retain formed Zn O therewith, providing sufficient volume for the associated expansion and maintaining thereby the mechanical stability and structure of the electrode—to enable many operation cycles of the rechargeable zinc-air batteries.

There is provided a secondary zinc battery including: a unit cell including; a positive-electrode plate including a positive-electrode active material layer and a positive-electrode collector; a negative-electrode plate including a negative-electrode active material layer containing zinc and a negative-electrode collector; an LDH separator covering or wrapping around the entire negative-electrode active material layer; and an electrolytic solution. The positive-electrode collector has a positive-electrode collector tab extending from one edge of the positive-electrode active material layer, and the negative-electrode collector has a negative-electrode collector tab extending from the opposite edge of the negative-electrode active material layer and beyond a vertical edge of the LDH-like compound separator. The unit cell can thereby collects electricity from the positive-electrode collector tab and the negative-electrode collector tab that are disposed at opposite edges of the unit cell. The LDH-like compound separator has at least two continuous closed edges.

An alkaline electrochemical cell includes a cathode, an anode which includes an anode active material, and a non-conductive separator disposed between the cathode and the anode, wherein from about 20% to about 50% by weight of the anode active material relative to a total amount of anode active material has a particle size of less than about 75 μm, and wherein the separator includes a unitary, cylindrical configuration having an open end, a side wall, and integrally formed closed end disposed distally to the open end.

An alkaline electrochemical cell, preferably a zinc/air cell which includes a container; a negative electrode, a positive electrode, wherein said negative electrode and said positive electrode are disposed within the container, and an alkaline electrolyte, wherein the negative electrode comprises zinc, a branched chain fluorosurfactant, barium sulfate (and, more specifically, amino- and/or epoxy-funcationalized barium sulfate) and nano sized zinc oxide. The negative electrode composition supports high zinc to electrolyte weight ratios.

An electrolyte additive is provided. The additive is a quaternary ammonium or phosphonium salt effective to suppress hydrogen evolution and metal dendrite formation during operation of a zinc electrochemical cell such as a zinc-air battery. A zinc battery cell is also provided, which contains an effective amount of the electrolyte additive.