Synthesis and electrochemical properties LiNi_(0.80)(Co_(0.20-x)Al_x)O_2(x = 0.0 and 0.05) cathodes for Li ion rechargeable batteries

摘要

The effect of simultaneous cobalt as well as aluminum doping was studied to understand their effect on the phase formation behavior and electrochemical properties of solution derived lithium nickel oxide cathode materials for rechargeable batteries. The discharge capacities of LiNi_(0.80)Co_(0.20)O_2 and LiNi_(0.80)Co_(0.15)Al_(0.05)O_2 cathodes, measured at constant current densities of 0.45 mA cm~(-2) in the cut-off voltage range of 4.3-3.2 V, were 100 and 136 mAh g~(-1), respectively. LiNi_(0.80)Co_(0.15)Al_(0.05)O_2 had better cycleability than the LiNi_(0.80)Co_(0.20)O_2 cathodes. The retention of undesirable Li_2CO_3 phase both in LiNi_(0.80)Co_(0.20)O_2 and LiNi_(0.80)Co_(0.15)Al_(0.05)O_2 cathodes was argued to be responsible for the relatively lower discharge capacity of these materials.