Optimization of the Synthesis Route for High Potential Cathodes (LiNi0.5Mn1.5O4)

SANSERVINO MIGUEL; JORGE THOMAS; VISINTIN A.

JUJUY

Workshop; IWLIME International Work shop,; 2016

IWLIME International Work shop,

The advance towards lithium ion batteries with higher performance is directly linked to the development of new active cathode materials. Therefore in order to obtain batteries with higher energy and power densities it is necessary to generate cathode materials with higher storage capacities and which can intercalate lithium at higher potentials. The most promising material for active cells operating at intermediate currents and high potentials is the LiNixMn2-xO4. These families of compounds have a potential near to 4.9V which is close to the maximum difference of potential that can be obtained from a redox battery. Moreover, the specific theoretical capacity of this family of compounds is 148mAh/g and generally can get real specific capacities greater than 130mAh/g . This group of materials has some drawbacks such as: working at high potentials the cycle life is low, mainly due to decomposition of the electrolyte. This problem is overcome with the use of additives in the formulation or changing the concentration. Another disadvantage is its low efficiency at high currents, a problem that has been partially solved by reducing the particle size. However in all cases the routes of solid phase synthesis require many steps and very long sintering time at high temperatures, consuming much energy when attempting to apply these methods to larger scales. In this work has tried to reduce the number of steps for the synthesis and the sintering time. Starting with Ni and Mn oxides and Li hydroxide, in stoichiometric proportions whit a thermal treatment at 350°C for 5h and then 850°C in a oxygen atmosphere whit different times (16hr ,22hr and 28hr) without pretreatment of the reagents.