Molten carbonate fuel cell - has lithium aluminate-lithium zirconate matrix to stabilise inside dia. by inhibiting recrystallisation

摘要

Molten carbonate fuel cell (MCFC) has a metallic current transfer plate (6), a cathode (2), a matrix (5) impregnated with Li2CO3 and K2CO3 melt (4), an anode (3) and another metallic current transfer plate (7), laminated in the given sequence. The matrix (5) consists of a mixt of LiAlO2 and Li2ZiO3. Pref. the molar ratio of LiAlO2:Li2ZrO3 is 90:10 to 50:50. The matrix is produced by mixing Al2O3 and ZrO2 powders (granulation pref. 0.05-1 micron), with addn. of a binder (i) and an emulsifying liq. (II); making this into a film; forming at 500-800 deg.C; placing in a melt contg. Li2CO3 and K2CO3 and converting it to LiAlO2 and Li2ZiO3 in this, with grain disintegration and increase in vol. (I) is PVA, methylcellulose, polyethylene glycol and/or linseed oil; and (II) liq. water, short-chain alcohols, e.g. MeOH, EtOH or glycol and/or phenol-water mixts. The matrix is formed at 550-700 deg.C and impregnated with the electrolyte by immersion in a melt of Li2CO3 and K2CO3, pref. by sucking the melt into the assembled fuel cell through the matrix and converted under the operating conditions in the melt. ADVANTAGE - The inside dia. of the MCFC is stabilised, i.e. recrystallisation is inhibited and the contact between the electrodes and transfer plates is fixed permanently, so that the internal structure of the electrodes is stable. (6pp Dwg.No.1/7)