An electrode for batteries that does not include a metal-film-type current collector is disclosed herein. In some embodiments, the electrode comprises a composite having a core-shell structure including a core having an electrode active material, and a metal material coated on or doped in the surface of the core. A secondary battery having the electrode has increased capacity and energy density and exhibits improved lifespan characteristics.

An electrode for batteries that does not include a metal-film-type current collector is disclosed herein. In some embodiments, the electrode comprises a composite having a core-shell structure including a core having an electrode active material, and a metal material coated on or doped in the surface of the core. A secondary battery having the electrode has increased capacity and energy density and exhibits improved lifespan characteristics.

A lithium secondary battery includes a cathode formed of a cathode active material including a lithium metal oxide particle having a concentration gradient, and a coating formed on the lithium metal oxide particle, the coating including aluminum, titanium and zirconium, an anode, and a separator interposed between the cathode and the anode. The cathode active material includes 2,000 ppm to 4,000 ppm of aluminum, 4,000 ppm to 9,000 ppm of titanium and 400 ppm to 700 ppm of zirconium, based on the total weight of the cathode active material. The performance of the secondary battery may be maintained under a high temperature condition.

A lithium secondary battery includes a cathode formed of a cathode active material including a lithium metal oxide particle having a concentration gradient, and a coating formed on the lithium metal oxide particle, the coating including aluminum, titanium and zirconium, an anode, and a separator interposed between the cathode and the anode. The cathode active material includes 2,000 ppm to 4,000 ppm of aluminum, 4,000 ppm to 9,000 ppm of titanium and 400 ppm to 700 ppm of zirconium, based on the total weight of the cathode active material. The performance of the secondary battery may be maintained under a high temperature condition.

A battery comprising an acidified metal oxide (“AMO”) material, preferably in monodisperse nanoparticulate form 20 nm or less in size, having a pH <7 when suspended in a 5 wt % aqueous solution and a Hammett function H.sub.0 >−12, at least on its surface.

A battery comprising an acidified metal oxide (“AMO”) material, preferably in monodisperse nanoparticulate form 20 nm or less in size, having a pH <7 when suspended in a 5 wt % aqueous solution and a Hammett function H.sub.0 >−12, at least on its surface.

Disclosed are a transition metal precursor for preparation of a lithium transition metal oxide, in which a ratio of tap density of the precursor to average particle diameter D50 of the precursor satisfies the condition represented by Equation 1 below, and a lithium transition metal oxide prepared using the same. $\begin{array}{cc}0<\frac{\mathrm{Tap}\mathrm{density}}{\begin{array}{c}\mathrm{Average}\mathrm{particle}\mathrm{diameter}D50\\ \mathrm{of}\mathrm{transition}\mathrm{of}\mathrm{metal}\mathrm{precursor}\end{array}}<3500\left(g/\mathrm{cc}.Math.\mathrm{cm}\right)& \left(1\right)\end{array}$

Disclosed are a transition metal precursor for preparation of a lithium transition metal oxide, in which a ratio of tap density of the precursor to average particle diameter D50 of the precursor satisfies the condition represented by Equation 1 below, and a lithium transition metal oxide prepared using the same. $\begin{array}{cc}0<\frac{\mathrm{Tap}\mathrm{density}}{\begin{array}{c}\mathrm{Average}\mathrm{particle}\mathrm{diameter}D50\\ \mathrm{of}\mathrm{transition}\mathrm{of}\mathrm{metal}\mathrm{precursor}\end{array}}<3500\left(g/\mathrm{cc}.Math.\mathrm{cm}\right)& \left(1\right)\end{array}$

Disclosed is a method for improving the performance of a layered electrode material. An interlayer spacing of the layered electrode material is measured and donated as (b). A salt compound is selected and added into a solvent with a molecular diameter of (c) to prepare an electrolytic solution, where a diameter (a) of a cation in the salt compound is smaller than the interlayer spacing (b), and c>b−a. The electrolytic solution is used as the working electrolytic solution for the layered electrode material.

The process of making a lithium ion battery cathode comprises the step of forming a slurry of an active material, a nano-size conductive agent, a binder polymer, a solvent and a dispersant. The solvent consists essentially of one or more of a compound of Formula 1, 2, or 3, and the dispersant comprises an ethyl cellulose.