A composite cathode active material represented by Li.sub.x(Co.sub.1−wM1.sub.w).sub.yPO.sub.4 (Formula 1) having an olivine structure, wherein a unit-cell volume of the composite cathode active material is in a range of about 283 Å.sup.3 to about 284.6 Å.sup.3. A cathode including the composite cathode active material, and a secondary battery including the composite cathode active material are also disclosed.

In Formula 1, M1 includes i) at least one of Sc, Ti, V, Cr, Cu, or Zn, and optionally at least one of Fe or Ni, and 0.9≤x≤1.1, 0.9≤y≤1.1, and 0<w≤0.3.

A composite nanoarchitecture unit is disclosed. The unit comprises a columnar film grown on top of another layer where the columns touch each other at the top forming arches having optimized characteristics. This nanoarchitecture unit, called nano-vault, achieves high mechanical stability for films under strong and variable stress action.

In fields related to battery cathode material technologies, a nano-silicon composite material and a preparation method thereof, an electrode material, and a battery are provided to resolve large volume expansion of a cathode material of a battery and a serious side reaction with an electrolyte. The nano-silicon composite material includes a core, a first coating layer, and a second coating layer. The core includes a nano-silicon crystal. The first coating layer covers a surface of the core. The first coating layer is of a porous structure. A material of the first coating layer includes bisilicate and silicon oxide in a deoxidized state. The second coating layer covers a surface of the first coating layer. A material of the second coating layer includes silicon dioxide in a deoxidized state.

An apparatus for vacuum-drying an electrode in a roll-to-roll state according to the present technology includes a low-vacuum evacuation device configured to evacuate a vacuum chamber to a low vacuum level, a medium-high-vacuum evacuation device connected to the vacuum chamber by a medium-high-vacuum pipe separate from a low-vacuum pipe and configured to evacuate the vacuum chamber to a medium vacuum level or a high vacuum level; and a control unit connected to the low-vacuum evacuation device and the medium-high-vacuum evacuation device and configured to regulate a vacuum level in the vacuum chamber stepwise to dry the electrode.

A method of forming a lithium or sodium foil for use as an electrode involves imposing a surface texturing that is predominately the {110} or {100} crystallographic orientation. For a Li {110} foil, a raw foil with a thickness of about 600 μm is heated to about 90° C. to randomize the crystallographic orientation and the foil is rolled to about 300 μm upon cooling. The rolled film is then scraped of about 50 μm of the lithium surface and heated to about 75° C. and rolled a second time to about 200 μm, and again cooled to room temperature. The cooled foil can be shaped into the electrode. The electrode can be employed in a battery to greatly extend the life of the battery relative to a lithium battery with a lithium anode that lacks the surface texturing. The alkali metal can be lithium electrochemically deposited on 3D scaffold such as carbon cloth with the deposited alkali metal maintaining the {110} texture.

Negative electrodes for electrochemical cells that cycle lithium ions are provided. The negative electrodes comprise electroactive material particles that exhibit a core-shell structure defining a core made of a lithiated silicon-based material and a shell surrounding the core that is a bi-layer structure including first and second carbon coating layers. An electrical conductivity of the first carbon coating layer is greater than that of the second carbon coating layer. A method of manufacturing a negative electrode material is provided in which a first carbon coating layer is formed on an outer surface of a silicon-based precursor particle. The silicon-based precursor particle is exposed to a lithium source to form a lithiated silicon-based particle having the first carbon coating layer. A second carbon coating layer is formed on the first carbon coating layer over the lithiated silicon-based particle to form an electroactive material particle.

In one embodiment, the present disclosure relates to a method of preparing a positive electrode active material, which includes mixing a nickel cobalt manganese hydroxide precursor containing nickel in an amount of 60 mol % or more based on a total number of moles of transition metals in the precursor, a lithium-containing raw material, and a doping raw material represented by Formula 2 (set forth herein), and sintering the mixture to prepare a positive electrode active material represented by Formula 1 (set forth herein).

Provided are a precursor solution, and a modified layer and a lithium-based battery prepared by using the same. The modified layer is formed on the negative electrode, the positive electrode and/or the separator of the lithium-based battery by using the precursor solution through photo-polymerization reaction or thermal curing. The lithium-based battery comprising the modified layer effectively promotes the charge and discharge capability, cycling life, and safety. The modified layer can be applied to a roll-to-roll process. The formation of lithium dendrites in the lithium-based battery comprising the modified layer is significantly suppressed or reduced during the charge-discharge cycles. The shuttle effect is effectively suppressed or reduced in lithium sulfur batteries and lithium iodine batteries. All the above effects are beneficial to increasing the product value of lithium ion batteries, lithium metal batteries, anode-free lithium batteries, lithium sulfur batteries, and lithium iodine batteries.

Systems and methods related to manufacturing of Lithium-Ion cells and Lithium-Ion cell cathode materials composed of LFP (Lithium Iron Phosphate) or LMFP (Lithium Manganese Iron Phosphate) are disclosed. In one exemplary implementation, there is provided a method of using a Nitrogen-containing plasma to treat the Lithium-Ion cell’s LFP or LMFP cathode materials. Moreover, the method may include treating the LFP or LMFP cathode materials before and/or after coating the cathode materials on a metal foil.

A method of producing electrodes includes selecting a palladium alloy, annealing the palladium alloy at a first temperature above 350° C., cold working the palladium alloy into a desired electrode shape, and annealing the palladium alloy at a second temperatures and for a time sufficient to produce a grain size between about 5 microns and about 100 microns. The method further includes etching the palladium alloy, rinsing the palladium alloy with at least one of water and heavy water, and storing the palladium alloy in an inert environment.