CONICET | Buscador de Institutos y Recursos Humanos

Manganese based Lithium-Rich materials represent a group of laminarcompounds with promising characteristics that could be protagonist fordevelopment of a new generation of rechargeable Li-ion batteries. Thesematerials could deliver high discharge capacities and high energy densitieswhich are enough for fulfill the requirements of electric cars and devices usedto storage energy coming from more clean and renewable sources. However, somedisadvantages still remain unsolved preventing their commercial or industrialuse [1]; like a rapid discharge capacity and voltage fade. In order to furtherunderstand the mechanics behind this process, two Lithium Rich materials, bothwith a composition of Li1.2Ni0.2Mn0.6O2,were synthetized; one through co-precipitation method (LiR-COP) [2] and theother through a simple, one step, solid state reaction method (LiR-SSR) [3].The LiR-COP material showed a well-defined activation of the Li2MnO3phase in the form of an intense peak in the cyclic voltammetrystudies and a longer plateau in the first cycle charge profile (Figure 1.a) and1.c). This phenomenon is apparently responsible for the higher dischargecapacity (200 mAh g-1) during the first 40 galvanostaticcharge-discharge cycles; on the other hand, this irreversible phase activationis also partially responsible for the capacity fade in comparison with theLiR-SSR material (Figure 1. d). Both materials showed an average dischargepotential of 3.5±0.1V through the first 10 charge-discharge cycles (Figure1.b). The results exhibited how the synthesis method greatly influence in theelectrochemical properties and how could these procedures be adjusted to getone step closer to the synthesis of a Li-Rich materials with a better cyclingperformance.

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