Lithium nickel oxide

An emerging electrochemical appHcation of lithium compounds is in molten carbonate fuel ceUs (qv) for high efficiency, low poUuting electrical power generation. The electrolyte for these fuel ceUs is a potassium carbonate—hthium carbonate eutectic contained within a lithium aluminate matrix. The cathode is a Hthiated metal oxide such as lithium nickel oxide. 

Lithium-nickel oxides form various lithium compounds, lithium hydroxides (LiOH), Li2C03, nickel hydroxide (Ni(OH)2), nickel carbonate (NiC03) and nickel oxide (NiO). Figure 51 shows the discharge characteristics of lithium-nickel oxides synthesized from these compounds. They were heat-treated at 850 °C for 20 h in air. Although the lithium nickel oxides showed a smaller discharge capacity than that of LiCo02, LiOH and Ni(OH)2 were considered to be appropi-ate raw materials. 

Figure 52. Discharge characteristics of some lithium-nickel oxides and LiCoO, (current density 0.25 mA cm2).

Finally, Al (/= 5/2) and Co NMR spectroscopy have been used to probe AP+ in Al-doped lithium cobalt oxides and lithium nickel oxides. A Al chemical shift of 62.5 ppm was observed for the environment Al(OCo)e for an AP+ ion in the transition-metal layers, surrounded by six Co + ions. Somewhat surprisingly, this is in the typical chemical shift range expected for tetrahedral environments (ca. 60—80 ppm), but no evidence for occupancy of the tetrahedral site was obtained from X-ray diffraction and IR studies on the same materials. Substitution of the Co + by AF+ in the first cation coordination shell leads to an additive chemical shift decrease of ca. 7 ppm, and the shift of the environment A1(0A1)6 (20 ppm) seen in spectra of materials with higher A1 content is closer to that expected for octahedral Al. The spectra are consistent with a continuous solid solution involving octahedral sites randomly occupied by Al and Co. It is possible that the unusual Al shifts seen for this compound are related to the Van-Vleck susceptibility of this compound. 

Escudero, M., Rodrigo, T., Soler, J., Daza, L. (2003). Electrochemical behaviour of lithium-nickel oxides in molten carbonate. /. Power Sources 118,23-34. 

Chang, C.-C., Kim, J.Y, and Kumta, P.N., Synthesis and electrochemical characterization of divalent cation-incorporated lithium nickel oxide, J. Electrochem. Soc., 147, 1722, 2000. 

Ganesan, P. Colon, H. Haran, B. White, R. Popov, N.B. Study of cobalt-doped lithium-nickel oxides as cathodes for MCFC. J. Power Sources 2002, 111 (1), 109-120. 

KINETICS OF REACTION OF DIOXYGEN WITH LITHIUM NICKEL OXIDE, AND THE ROLE OF SURFACE OXYGEN IN OXIDATIVE COUPLING OF METHANE... 

Barium sulfate Calcium plumbate Cobalt sulfate (ous) Lead Lead oxide, black Lead sulfate Lithium Nickel oxide (ic) batteries, storage/dry cell Zinc... 

Peres JP, Delmas C, Rougier A, Broussely M, Perton F, Biensan P, Willman P (1996) The relationship between the composition of lithium nickel oxide and the loss of reversibility during the first cycle. J Phys Chem Solids 57 1057-1060... 

Kawaji H, Oka T, Tojo T, Atake T, Hirano A, Kanno R (2002) Low-temperature heat capacity of layer structure lithium nickel oxide. Solid State Ionics 152-153 195-198... 

Lithium nickel oxide is isostructural with lithium cobalt oxide and has higher specific capacity. However, it is much more susceptible to thermal runaway and has not been used in commercially lithium-ion cells. 

Lithium Nickel Oxide Derivatives LiNi0.sCo0.2O2 and LiNi0.sCo0.15Nl0.05O2... 

Preparing LiNi02 with an excess amount of Li was found to be one of the methods to produce stoichiometric cathode material. Another, even more effective method for stabihzing the lithium nickel oxide structure was the introduction of cobalt and thus formation of the hthiated nickel cobalt oxide derivatives of LiNi02 material. These findings led to laboratory development and commercial production of various derivatives of lithium nickel oxide, summarized in Table 1.4. 

Figure 2.52 shows the discharge characteristics of LiCo02 and Uthium-nickel oxides prepared from LiOH and Ni(OH)2 at 650, 750, and 850 °C. lithium-nickel oxide heat-treated at 750 °C showed nearly the same discharge capacity as IiCo02 while the discharge potential was lower than that of LiCo02. Composition of these... 

The metal oxides used to make positive electrode materials for lithium-ion batteries commonly include lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, vanadium oxide, and various others, such as iron oxides. Positive electrode materials of 5 V and polyanion-type positive electrode materials (so far mainly referring to lithium iron phosphate, LiFeP04) have also been investigated. Among the primary materials for these positive electrode materials, cobalt is the most expensive, followed by nickel and then manganese and vanadium. As a result, the prices of positive electrode materials are basically in line with the market prices of the primary materials. The structures of these positive electrode materials are mainly layered, spinel, and oliven. 

Wang GX, Bewlay S, Yao J (2003) Multiple-ion doped lithium nickel oxides as cathode materials for lithium-ion batteries. J Power Sourc 119-121 189-194... 

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