Synthesis of cathode material LiNi1-y Co y O2 by a simplified combustion method

Abstract

The optimum conditions for synthesizing LiNi 1-y Co y O 2 (y=0.1, 0.3 and 0.5) by a simplified combustion method, in which the preheating step is omitted, and the electrochemical properties of these materials were investigated. The optimum condition for synthesizing LiNi 0.9 Co 0.1 O 2 by the simplified combustion method is calcination at 800°C for 12 h in air in 3.6 mole ratio of urea to nitrate. The LiNi 0.9 Co 0.1 O 2 synthesized under these conditions shows the smallest R-factor{(I 006 +I 102 )/I 101 } and the largest I 003 /I 104 , indicating better hexagonal ordering and less cation mixing, respectively. The LiNi 0.7 Co 0.3 O 2 synthesized at 800°C for 12 h in air in 3.6 mole ratio of urea to nitrate has the largest first discharge capacity 156.2 mA h g )1 at 0.5C and shows relatively good cycling performance. This sample shows better hexagonal ordering and less cation mixing than the other samples. The particle size of the LiNi 0.7 Co 0.3 O 2 is relatively small and its particles are spherical with uniform particle size.

Synthesis, Characterization and Charge-Discharge Profile of LiMn_0.3Co_0.3Ni_0.3Fe_0.1O₂ Prepared via Sol-Gel Method

“…This indicates that, this is the best annealing condition to synthesize 333Fe using this method which is in agreement with the values of I(003)/I(104) and R-factor shown in Table 1. This sample possesses the highest hexagonal order among those annealed at 800 ˚C as well as the one with the least cation mixing [10]. It also can be observed that the sample annealed at 800 ˚C for 24 h exhibits the worst performance with not only the lowest discharge capacity, but it also suffers the largest capacity loss after ten cycles.…”

“…In general, the cyclability of the 333Fe compounds are good with all the materials exhibit small capacity loss, except the one annealed at 800˚ C for 24 h which suffers more than 10 % capacity loss after ten cycles. The cyclability is improved as the annealing temperature increased due to the improved crystallinity from multi-phase transition to single phase transition [10].…”

Synthesis of LiMn1.9Ti0.09Si0.01O4 by self-propagating combustion method

“…LiCoO 2 cathode has a well-ordered layered crystal structure and fast lithium extraction/insertion but it suffers from three major restrictions which is toxicity, scarcity and cost [1]. Lithium manganese oxides LiMn 2 O 4 was introduced as a safer and cheaper material [2,3].…”

Variation of LiNiO2 cathode properties with substitution of Ga, In and Tl by the combustion method

“…To improve the electrochemical properties of LiNiO 2 , Co [17][18][19][20][21], Al [22][23][24][25], Ti [26][27][28][29][30], Ga [31], Mn [32] and Fe [33][34][35][36] ions were substituted for lithium ion. Rougier et al [18] reported that the stabilization of the two-dimensional character of the structure by cobalt substitution in LiNiO 2 is correlated with an increase in the cell performance due to the decrease in the amount of extra-nickel ions in the inter-slab space which impede the lithium diffusion.…”