NOVELTY - A composition (C1) of nanoscale lithium alloy particles comprises alloy particles having uniform particle size and being configured so as to maintain a body centered cubic crystal structure during insertion and removal of lithium from the alloy during an electrochemical process.    USE - As nanoscale lithium composition useful in electrochemical application e.g. electrodes and batteries; in lithium-ion batteries (claimed), fuel cells, and capacitors.    ADVANTAGE - The composition comprising nanoscale lithium alloy particles have improved stability. The nanoscale lithium alloy has a body centered cubic (BCC) crystal structure, which minimizes phase expansion during discharge and recharge in a battery. The crystal structure of the nanoscale lithium compositions is preferably body centered cubic, allowing low volume expansion and high diffusivity of lithium from or into the core structures during discharge and charge processes, respectively. The lithium compositions comprising alloyed nanoscale particles impart stability to highly reactive Li nanoparticles in electrochemical processing environments. The lithium compositions maintain a BCC crystalline structure during lithium (Li) insertion and removal processes. Because there is little or no crystallographic stress involved in Li removal and incorporation, a BCC structure can lead to much longer cycle life during charge and discharge of Li from the compositions. Thus, alloyed lithium nanoparticles are a compromise between increased stability and decreased specific capacity relative to pure lithium metal, while maintaining a crystal structure that minimizes volume expansion, and thus improves cycling ability. It shows faster kinetics of Li removal and insertion. Faster kinetics of Li movement in turn enables faster charging and discharging of the rechargeable Li battery. The Li content within the alloy can be high, resulting in increased capacity. Alloys made at the nanoscale have more uniform composition and more homogeneous crystallographic morphology than a lithium particle-host configuration, improving lithium diffusion kinetics. Further, binders and additives can be more uniformly coated on the particles, resulting in improved conductivity properties.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) preparing (M1) nanoscale body-centered cubic lithium alloy involving bringing together lithium and a metallic or semi-metallic alloying material to form an alloy, vaporizing the alloy to form an alloy vapor, and directing a cooling gas over the alloy vapor to form nanoscale alloy particles (A1) having uniform particle size, and the alloy nanoscale particles being configured so as to maintain a body centered cubic crystal structure during insertion and removal of lithium from the alloy during an electrochemical process;    (2) preparing an electrode (A2) using the nanoscale particles (A1) involving dispersing the nanoscale alloy particles in a medium to form a liquid ink; depositing a layer of the ink onto a current collector; and evaporating liquids from the ink to form a dry film;    (3) making a battery involving making an electrode (A2) and combining it with a transmission medium configured to transmit lithium ions, where the electrode serving as either the anode or the cathode of the battery;    (4) an electrode (A3) comprising a current collector configured to receive an electrical connection and a film disposed on the current collector, where the film comprises an ink comprising the composition (C1);    (5) a battery (A4) comprising the electrode (A3), and a transmission medium configured to transmit lithium ions, where the electrode serving as either the anode or the cathode of the battery;    (6) core-shell structured nanoparticles comprising a lithium metal or lithium alloy core; and a shell disposed over the core, where the shell is configured to conduct lithium ions to and from the core;    (7) an electrode (A5) comprising a current collector configured to receive an electrical connection, where the current collector comprises nanoparticles, and at least a portion of the nanoparticles comprises a lithium metal or lithium alloy core and a shell disposed over the core, and the shell is configured to conduct lithium ions to and from the core;    (8) a battery comprising an anode and cathode, where at least one of the anode or cathode comprises nanoparticles comprising a lithium metal or lithium alloy core and a shell disposed over the core, and the shell is configured to conduct lithium ions to and from the core; and a transmission medium configured to transmit lithium ions between the anode and the cathode; and    (9) charging a lithium ion battery involving applying a current to an electrode comprising core-shell structured nanoparticles, where at least a portion of nanoparticles comprise a lithium metal or lithium alloy core and a shell comprising lithium nitride disposed over the core; allowing lithium ions to migrate through the shells; and reincorporating the lithium ions into vacancies in the lithium metal or lithium alloy core crystallographic structures.