Active material for rechargeable batteries
View Patent ↗A mixed metal hydroxide with brucite structure is described, which contains nickel hydroxide as its main component and at least one trivalent metal selected from the group consisting of Co, Fe, Al, Ga, In, Sc, Y and La in an amount of from about 12 to about 30 atom % relative to the sum of the metal components including Ni. The invention also relates to a rechargeable battery containing a mixed metal hydroxide according to the invention as an electrochemically active material as well as a secondary batter containing the mixed metal hydroxide. The invention also relates to a process for producing a mixed metal hydroxide having a brucite structure.
1. A mixed metal hydroxide, with a brucite structure, comprising:
(a) a nickel hydroxide component; and
(b) a trivalent metal consisting of
(i) a first metal selected from the group consisting of Fe, Al and combinations thereof, and
(ii) optionally a second metal selected from the group consisting of Co, Ga, In, Sc, Y, La and combinations thereof,
said trivalent metal being present in an amount ranging from 12 to 30 atom % relative to the sum of the metal components including Ni,
wherein the mixed metal hydroxide has a brucite structure and a nickel layer spacing determinable by X-ray diffraction, that ranges from 4.3 Å to 4.8 Å.
2. The mixed metal hydroxide of claim 1 , wherein the mixed metal hydroxide contains from 12 to 25 atom % Al.
3. The mixed metal hydroxide of claim 1 , wherein said second metal (b)(ii) is present and is Co, the mixed metal hydroxide containing from 4 to 9 atom % Co.
4. A rechargeable battery comprising the mixed metal hydroxide of claim 1 as an electrochemically active material.
5. A secondary battery comprising the mixed metal hydroxide of claim 1 .
6. The mixed metal hydroxide of claim 1 wherein said trivalent metal (b) consists of Al and Co with an atomic ratio of Al to Co of 2 to 4.
7. A mixed metal hydroxide comprising:
(a) a nickel hydroxide component; and
(b) a trivalent metal consisting of
(i) a first metal selected from the group consisting of Fe, Al and combinations thereof, and
(i) optionally a second metal selected from the group consisting of Co, Ga, In, Sc, Y, La and combinations thereof,
the trivalent metal being present in an amount ranging from 12 to 20 atom % relative to the sum of the metal components including Ni,
wherein the mixed metal hydroxide further comprises at least one element selected from the group consisting of Mn, Cr, Ti, Zr and Cu, in which the at least one element is different from the trivalent metal, the at least one element being present in a positive amount of up to 15 atom %, relative to the sum of all metal components,
further wherein the mixed metal hydroxide has a brucite structure and a nickel layer spacing, determinable by X-ray diffraction, that ranges from 4.3 Å to 4.8 Å.
8. A rechargeable battery comprising the mixed metal hydroxide of claim 7 as an electrochemically active material.
9. A secondary battery comprising the mixed metal hydroxide of claim 7 .
10. The mixed metal hydroxide of claim 7 wherein said trivalent metal (b) consists of Al and Co with an atomic ratio of Al to Co of 2 to 4.