A bipolar electrode (100) for a metal hydride battery includes a current collector (10), a negative electrode active material layer (20) provided on a first surface (10A) of the current collector (10), and a positive electrode active material layer (30) provided on a second surface (10B) of the current collector (10). The negative electrode active material layer (20) contains a metal hydride. The current collector (10) includes a steel sheet (13) and a NiFe alloy layer (15) formed on at least one surface of the steel sheet (13).

Provided are uniquely structured electrochemically active particles characterized by a first electrochemically active material and a second electrochemically active material disposed about the first material whereby at least the second material includes a modifier present as a continuous transition concentration gradient from the first material into the second material whereby the concentration is lower in the first material than the second material. Also provided are processes of producing the particle and electrochemical cells incorporating the particles as a positive electrode material in a cathode.

Provided are uniquely structured electrochemically active particles characterized by a first electrochemically active material and a second electrochemically active material disposed about the first material whereby at least the second material includes a modifier present as a continuous transition concentration gradient from the first material into the second material whereby the concentration is lower in the first material than the second material. Also provided are processes of producing the particle and electrochemical cells incorporating the particles as a positive electrode material in a cathode.

Disclosed are a transition metal precursor for preparation of a lithium composite transition metal oxide, the transition metal precursor including a composite transition metal compound represented by Formula 1 below and a hydrocarbon compound, and a method of preparing the same:
Mn.sub.aM.sub.b(OH.sub.1-x).sub.2(1)
wherein M is at least two selected from the group consisting of Ni, Co, Mn, Al, Cu, Fe, Mg, B, Cr, and second period transition metals; 0.4a1; 0b0.6; a+b1; and 0x0.5, in which the transition metal precursor includes a particular composite transition metal compound and a hydrocarbon compound, and thus, when a lithium composite transition metal oxide is prepared using the same, carbon may be present in lithium transition metal oxide particles and/or on surfaces thereof, whereby a secondary battery including the lithium composite transition metal oxide exhibits excellent rate characteristics and long lifespan.

A method of fabricating a 3D porous electrode architecture comprises forming a microbattery template that includes (a) a lattice structure comprising a first lattice portion separated from a second lattice portion on a substrate, and (b) a solid structure on the substrate including a separating portion between the first and second lattice portions. Interstices of the first lattice portion are infiltrated with a first conductive material and interstices of the second lattice portion are infiltrated with a second conductive material. Each of the first and second conductive materials fill the interstices to reach a predetermined thickness on the substrate. The solid structure and the lattice structure are removed from the structure, thereby forming first and second conductive scaffolds comprising a porosity defined by the lattice structure and having a lateral size and shape defined by walls of the solid structure.