A process for recovering a nickel cobalt manganese hydroxide from recycled lithium-ion battery (LIB) material such as black mass, black powder, filter cake, or the like. The recycled LIB material is mixed with water and either sulfuric acid or hydrochloric acid at a pH less than 2. Cobalt, nickel, and manganese oxides from the recycled lithium-ion battery material dissolve into the acidic water with the reductive assistance of gaseous sulfur dioxide. Anode carbon is filtered from the acidic water, leaving the dissolved cobalt, nickel, and manganese oxides in a filtrate. The filtrate is mixed with aqueous sodium hydroxide at a pH greater than 8. Nickel cobalt manganese hydroxide precipitates from the filtrate. The nickel cobalt manganese hydroxide is filtered from the filtrate and dried. The filtrate may be treated ammonium fluoride or ammonium bifluoride to precipitate lithium fluoride from the filtrate. The composition ratio of nickel to cobalt to manganese in the acid filtrate may be adjusted to a desired ratio. The anode carbon is recovered and purified for reuse.

A method for manufacturing a cobalt based hydroxide carbonate compound having a malachite-rosasite mineral structure, comprising the steps of: providing an first aqueous solution comprising a source of Co, providing a second aqueous solution comprising Na.sub.2CO.sub.3, mixing both solutions in a precipitation reactor at a temperature above 70° C., thereby precipitating a cobalt based hydroxide carbonate compound whilst evacuating from the reactor any CO.sub.2 formed by the precipitation reaction, wherein the residence time of the compound in the reactor is between 1 and 4 hours, and recovering the cobalt based hydroxide carbonate compound. The cobalt based hydroxide carbonate compound is used as a precursor of a lithium cobalt based oxide usable as an active positive electrode material in lithium ion batteries.

The invention is directed towards an electrochemically active cathode material. The electrochemically active cathode includes beta-delithiated layered nickel oxide and an electrochemically active cathode material selected from the group consisting of manganese oxide, manganese dioxide, electrolytic manganese dioxide (EMD), chemical manganese dioxide (CMD), high power electrolytic manganese dioxide (HP EMD), lambda manganese dioxide, gamma manganese dioxide, beta manganese dioxide, and mixtures thereof. The beta-delithiated layered nickel oxide has an X-ray diffraction pattern. The X-ray diffraction pattern of the beta-delithiated layered nickel oxide includes a first peak from about 14.9°2θ to about 16.0°2θ; a second peak from about 21.3°2θ to about 22.7°2θ; a third peak from about 37.1°2θ to about 37.4°2θ; a fourth peak from about 43.2°2θ to about 44.0°2θ; a fifth peak from about 59.6°2θ to about 60.6°2θ; and a sixth peak from about 65.4°2θ to about 65.9°2θ.

The invention is directed towards an electrochemically active cathode material. The electrochemically active cathode includes beta-delithiated layered nickel oxide and an electrochemically active cathode material selected from the group consisting of manganese oxide, manganese dioxide, electrolytic manganese dioxide (EMD), chemical manganese dioxide (CMD), high power electrolytic manganese dioxide (HP EMD), lambda manganese dioxide, gamma manganese dioxide, beta manganese dioxide, and mixtures thereof. The beta-delithiated layered nickel oxide has an X-ray diffraction pattern. The X-ray diffraction pattern of the beta-delithiated layered nickel oxide includes a first peak from about 14.9°2θ to about 16.0°2θ; a second peak from about 21.3°2θ to about 22.7°2θ; a third peak from about 37.1°2θ to about 37.4°2θ; a fourth peak from about 43.2°2θ to about 44.0°2θ; a fifth peak from about 59.6°2θ to about 60.6°2θ; and a sixth peak from about 65.4°2θ to about 65.9°2θ.

Other Metals are uniformly doped in a sodium transition metal oxide particle to obtain a cathode active material. As a result, it is possible to improve the battery performance by improving the physical properties of the material itself and stabilizing the structure during the charge/discharge process as well as electrochemical properties.

A battery system includes a nickel hydride battery and an electronic control unit. The electronic control unit is configured to store data indicating a corresponding relationship between an elapsed time from start of use of the nickel hydride battery and a memory quantity. The data are data determined in a classified manner individually for each of conditions of use that are defined in such a manner as to include an open circuit voltage and a temperature. The electronic control unit is configured to sequentially calculate, with reference to the data, the memory quantity within a time when classification of the conditions of use does not change. The memory quantity is a quantity indicating an amount of change in voltage resulting from a memory effect. The electronic control unit is configured to estimate a current memory quantity of the nickel hydride battery by integrating the calculated memory quantity.

A battery system includes a nickel hydride battery and an electronic control unit. The electronic control unit is configured to store data indicating a corresponding relationship between an elapsed time from start of use of the nickel hydride battery and a memory quantity. The data are data determined in a classified manner individually for each of conditions of use that are defined in such a manner as to include an open circuit voltage and a temperature. The electronic control unit is configured to sequentially calculate, with reference to the data, the memory quantity within a time when classification of the conditions of use does not change. The memory quantity is a quantity indicating an amount of change in voltage resulting from a memory effect. The electronic control unit is configured to estimate a current memory quantity of the nickel hydride battery by integrating the calculated memory quantity.

A nickel-hydrogen secondary battery includes an electrode group comprising a separator, a positive electrode, and a negative electrode, and the positive electrode contains a positive electrode active material including a base particle comprising a nickel hydroxide particle containing Mn in solid solution and a conductive layer comprising a Co compound and covering the surface of the base particle, wherein the X-ray absorption edge energy of Mn detected within 6500 to 6600 eV by measurement with an XAFS method is 6548 eV or higher.

A nickel-hydrogen secondary battery includes an electrode group comprising a separator, a positive electrode, and a negative electrode, and the positive electrode contains a positive electrode active material including a base particle comprising a nickel hydroxide particle containing Mn in solid solution and a conductive layer comprising a Co compound and covering the surface of the base particle, wherein the X-ray absorption edge energy of Mn detected within 6500 to 6600 eV by measurement with an XAFS method is 6548 eV or higher.

The invention is directed towards a cathode. The cathode includes an electrochemically active cathode material and at least one cathode additive. The at least one cathode additive includes a head group and at least one hydrocarbon tail group. The head group includes at least one p-element atom that is bonded to a second p-element atom. The at least one p-element atom has an electronegativity and the second p-element atom has an electronegativity. The electronegativity of the at least one p-element atom is different from the electronegativity of the second p-element atom.