The effect of fuel type on the performance of a direct carbon fuel cell with molten alkaline electrolyte

• The effect of nine carbonacious fuels on the operation of a DCFC was investigated.
• The tests were performed at 723 K and the air flow rate of 0.5 dm3 min−1.
• Binary eutectic mixture of Na/Li hydroxides was used as electrolyte.
• The results for a biochar fuel were similar to those obtained for hard coals.

In the paper the behavior of various carbon-rich materials used as fuels for the direct carbon fuel cell (DCFC) with molten hydroxide electrolyte is presented. For the current research various carbonaceous fuels (e.g., different biochars, hard coal, graphite, carbon black) were tested. The electrolyte was the binary eutectic mixture of sodium and lithium hydroxides (90 mol.% NaOH – 10 mol.% LiOH). The fuel cell was operated at 723 K and cathode air flow rate of 0.5 dm3 min−1. The maximum power densities were achieved for raw coal and commercial biochar and made up 38.6 mW cm−2 and 32.8 mW cm−2, respectively.