Development of a high-rate, rechargeable bipolar LiAl/FeS{sub 2} battery

摘要: Materials refinements have improved bipolar Li-Al/FeS{sub 2} batteries for power-demand applications. Current technology uses a two-phase Li-alloy cathode, LiCl-LiBr-KBr electrolyte, and an upper-plateau (UP) FeS{sub anode battery operated at 440 C; the is in sealed form. The Li alloy ({alpha}+{beta} Li-Al Li{sub 5}Al{sub 5}Fe{sub 2}) cathode provides situ overcharge tolerance that makes design viable. use of LiCl-rich electrolyte ``electrolyte-starved`` cells achieves low-burdened with low area-specific impedance, MgO powder separator. Combining dense UP electrodes CuFeS{sub additive LiI-modified produces stable reversible couple, high power capabilities. Long cycle life depends on peripheral seals each cell stack. Seal composition based sulfide ceramic/sealant materials produce strong bonds between metals ceramics. Using these seals, four-cell stacks are being built tested (25 Ah, 13-cm dia). Adding 5 mol% LiI to increased specific energy by 50% under 140 W/kg, constant C/1 rate 544 W/kg pulse (8-s) schedule. Cell capacity high-power pulse-demand approximates C/3 discharge capacity. 155 Wh/kg rate.