An anode for batteries having a columnar nanostructured porous germanium for its active material. This nanostructured porous germanium can be produced with the novel etching method disclosed herein. Such anode can be easily mass-produced with the presented method that requires pre-existing, affordable and easy to integrate equipment. In some embodiments, the produced columnar porous germanium can be directly used as a monolithic anode after its etching nanostructuration for on-chip anodes for example, where the anisotropic nanostructured germanium acts as the active material and where the remaining bulk germanium layer act as the current collector. This can be easily implemented in lithium batteries. The cycle life of such anodes could be extended by a factor of 26 and 1.8 for high rate and high energy applications, respectively.

Provided herein are energy storage devices comprising a first electrode comprising a layered double hydroxide, a conductive scaffold, and a first current collector; a second electrode comprising a hydroxide and a second current collector; a separator; and an electrolyte. In some embodiments, the specific combination of device chemistry, active materials, and electrolytes described herein form storage devices that operate at high voltage and exhibit the capacity of a battery and the power performance of supercapacitors in one device.

A fuel cell according to the present disclosure includes a flat plate-shaped metal porous body having a framework of a three-dimensional network structure as a gas diffusion layer. The framework is made of metal or alloy. In the metal porous body, a ratio of an average pore diameter in a direction parallel to a gas flow direction to an average pore diameter in a direction perpendicular to the gas flow direction is greater than or equal to 1.4 and less than or equal to 2.5.

A fuel cell according to the present disclosure includes a flat plate-shaped metal porous body having a framework of a three-dimensional network structure as a gas diffusion layer. The framework is made of metal or alloy. In the metal porous body, a ratio of an average pore diameter in a direction parallel to a gas flow direction to an average pore diameter in a direction perpendicular to the gas flow direction is greater than or equal to 1.4 and less than or equal to 2.5.

A composite structure is adapted to a separator of a secondary battery, and includes a compact layer containing a solid electrolyte and a porous layer which contains a solid electrolyte and is integrally formed with the compact layer without having a bonding interface.

A composite structure is adapted to a separator of a secondary battery, and includes a compact layer containing a solid electrolyte and a porous layer which contains a solid electrolyte and is integrally formed with the compact layer without having a bonding interface.

A hybrid series battery module includes a first-type battery cell including a first negative electrode plate and a second-type battery cell including a second negative electrode plate. Energy density of the first-type battery cell is less than energy density of the second-type battery cell. A first interlayer spacing of a negative electrode active material of the first negative electrode plate is greater than a second interlayer spacing of a negative electrode active material of the second negative electrode plate. In a state of charge of 0%, a ratio of the first interlayer spacing to the second interlayer spacing falls within a range of greater than or equal to 1.005 and less than or equal to 1.600.

A hybrid series battery module includes a first-type battery cell including a first negative electrode plate and a second-type battery cell including a second negative electrode plate. Energy density of the first-type battery cell is less than energy density of the second-type battery cell. A first interlayer spacing of a negative electrode active material of the first negative electrode plate is greater than a second interlayer spacing of a negative electrode active material of the second negative electrode plate. In a state of charge of 0%, a ratio of the first interlayer spacing to the second interlayer spacing falls within a range of greater than or equal to 1.005 and less than or equal to 1.600.

A battery electrode, comprising a current collector, an active material layer on the current collector, and an insulative porous film on the active material layer, wherein the insulative porous film comprises particles of an inorganic oxide and particles of an adsorbent.

A battery electrode, comprising a current collector, an active material layer on the current collector, and an insulative porous film on the active material layer, wherein the insulative porous film comprises particles of an inorganic oxide and particles of an adsorbent.