Methods of making metal-doped nickel oxide active materials

#This invention relates to methods of making cathode active materials, and more particularly to methods of making nickel (IV)-containing cathode active materials.

#Batteries, such as alkaline batteries, are commonly used as electrical energy sources. Generally, a battery contains a negative electrode (anode) and a positive electrode (cathode). The negative electrode contains an electroactive material (such as zinc particles) that can be oxidized; and the positive electrode contains an electroactive material (such as manganese dioxide) that can be reduced. The active material of the negative electrode is capable of reducing the active material of the positive electrode. In order to prevent direct reaction of the active material of the negative electrode and the active material of the positive electrode, the electrodes are mechanically and electrically isolated from each other by an ion-permeable separator.

#When a battery is used as an electrical energy source for a device, such as a cellular telephone, electrical contact is made to the electrodes, allowing electrons to flow through the device and permitting the oxidation and reduction reactions to occur at the respective electrodes to provide electrical power. An electrolyte solution in contact with the electrodes contains ions that diffuse through the separator between the electrodes to maintain electrical charge balance throughout the battery during discharge.

#FIG. 1 is a schematic side sectional view of an alkaline primary round cell/battery.

#FIG. 2 is a plot depicting the Ni-rich portion of the ternary composition diagram for Li—Ni—Co—Mg and Li—Ni—Co—Al oxide systems, indicating the compositions of 28 metal-doped lithium nickel oxides, which are precursors to the corresponding delithiated (i.e., lithium deficient) metal-doped nickel (IV) oxides.

#FIG. 3 is a plot depicting an overlay of the x-ray powder diffraction patterns for cobalt, and cobalt and magnesium-doped lithium nickel oxide compositions, and undoped lithium nickel oxide, measured using Cu Kα radiation and scanned between 17 and 46 degrees 2θ.

#Like reference symbols in the various drawings indicate like elements.

#Referring to FIG. 1, a battery 10 includes a cylindrical housing 18, a cathode 12 in the housing, an anode 14 in the housing, and a separator 16 between the cathode and the anode. Battery 10 also includes a current collector 20, a seal 22, and a metal top cap 24, which serves as the negative terminal for the battery. Cathode 12 is in contact with housing 18, and the positive terminal of battery 10 is at the opposite end of battery 10 from the negative terminal. An electrolyte solution, e.g., an alkaline solution, is dispersed throughout battery 10.

#Cathode 12 can include an electrochemically active material having a doped alkali-deficient nickel oxide that optionally includes protons, an electrically conductive additive, and optionally a binder.