The invention relates to the field of alkaline electrochemical cells and more specifically to that of batteries. More specifically, the invention pertains to a secondary electrochemical cell with a zinc electrode, which is differentiated in that it comprises: a) an electrolyte which is an alkaline aqueous solution whose molarity is between 4 M and 15 M hydroxyl anions, comprising soluble silicates whose concentration expressed as silica (SiO.sub.2) is between 0.15 g/l and 80 g/l; and b) a zinc electrode containing a conductive ceramic at least partly consisting of hafnium nitride and/or carbide and/or magnesium carbide and/or nitride and/or silicide and/or niobium carbide and/or nitride and/or titanium carbide and/or nitride and/or silicide and/or vanadium nitride acid/or of double carbides and/or nitrides of any two metals selected among hafnium, magnesium, niobium, titanium and vanadium.

The invention relates to the field of alkaline electrochemical cells and more specifically to that of batteries. More specifically, the invention pertains to a secondary electrochemical cell with a zinc electrode, which is differentiated in that it comprises: a) an electrolyte which is an alkaline aqueous solution whose molarity is between 4 M and 15 M hydroxyl anions, comprising soluble silicates whose concentration expressed as silica (SiO.sub.2) is between 0.15 g/l and 80 g/l; and b) a zinc electrode containing a conductive ceramic at least partly consisting of hafnium nitride and/or carbide and/or magnesium carbide and/or nitride and/or silicide and/or niobium carbide and/or nitride and/or titanium carbide and/or nitride and/or silicide and/or vanadium nitride acid/or of double carbides and/or nitrides of any two metals selected among hafnium, magnesium, niobium, titanium and vanadium.

Provided herein is a battery and an electrode. The battery may include two electrodes; and an electrolyte, wherein at least one electrode further includes: a nano-scale coated network, which includes one or more first carbon nanotubes electrically connected to one or more second carbon nanotubes to form a nano-scale network, wherein at least one of the one or more second carbon nanotubes is in electrical contact with another of the one or more second carbon nanotubes. The battery may further include an active material coating distributed to cover portions of the one or more first carbon nanotubes and portions of the one or more second carbon nanotubes, wherein a plurality of the one or more second carbon nanotubes are in electrical communication with other second carbon nanotubes under the active material coating. Also provided herein is a method of making a battery and an electrode.

Provided herein is a battery and an electrode. The battery may include two electrodes; and an electrolyte, wherein at least one electrode further includes: a nano-scale coated network, which includes one or more first carbon nanotubes electrically connected to one or more second carbon nanotubes to form a nano-scale network, wherein at least one of the one or more second carbon nanotubes is in electrical contact with another of the one or more second carbon nanotubes. The battery may further include an active material coating distributed to cover portions of the one or more first carbon nanotubes and portions of the one or more second carbon nanotubes, wherein a plurality of the one or more second carbon nanotubes are in electrical communication with other second carbon nanotubes under the active material coating. Also provided herein is a method of making a battery and an electrode.

A negative electrode active material for aqueous secondary batteries, said negative electrode active material being applied to an aqueous secondary battery that uses an aqueous electrolyte solution containing water and a lithium salt, wherein: the negative electrode active material contains graphite; the graphite has a C—F bond group on the surface; if I.sub.688eV is the peak intensity at around 688 eV ascribed to a C—F bond and I.sub.284eV is the peak intensity at around 284 eV ascribed to a C—C bond in the XPS spectrum of the graphite as obtained by X-ray photoelectron spectroscopy, the ratio of the peak intensity I.sub.688eV to the peak intensity I.sub.284eV (namely, the value of I.sub.688eV/I.sub.284eV ) is from 0.1 to 7; and the BET specific surface area is from 0.5 m.sup.2/g to 3.9 m.sup.2/g.

A negative electrode active material for aqueous secondary batteries, said negative electrode active material being applied to an aqueous secondary battery that uses an aqueous electrolyte solution containing water and a lithium salt, wherein: the negative electrode active material contains graphite; the graphite has a C—F bond group on the surface; if I.sub.688eV is the peak intensity at around 688 eV ascribed to a C—F bond and I.sub.284eV is the peak intensity at around 284 eV ascribed to a C—C bond in the XPS spectrum of the graphite as obtained by X-ray photoelectron spectroscopy, the ratio of the peak intensity I.sub.688eV to the peak intensity I.sub.284eV (namely, the value of I.sub.688eV/I.sub.284eV ) is from 0.1 to 7; and the BET specific surface area is from 0.5 m.sup.2/g to 3.9 m.sup.2/g.

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 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 cathode material of an aqueous zinc-ion battery and an aqueous zinc-ion battery are described. The aqueous zinc-ion battery has a cathode material of the aqueous zinc-ion battery of the embodiment of the present disclosure, which has a specific ratio of specific cathode material. At a specific current density (50 mA/g), an electrochemical capacity of the aqueous zinc-ion battery can reach about 500 mAh/g, and a capacity can reach 200 mAh/g at a current density of 20 A/g.