Table 2.

The figures of merit of cylindrical SC-MFCs with increasing radius (r).

Size		Eq.	r
1.5 cm	3 cm	4 cm	5 cm
Anode	rbrush = 1.5 cm h = 3 cm
Cathode	h = 3 cm area = 2 π r h, with r > rbrush lowest area = 28.3 cm2		28.3 cm2	56.5 cm2	75.5 cm2	94.2 cm2
Cell	h = 3 cm volume = π r2 h, with r > rbrush lowest volume = 21.2 cm3		21.2 cm3	85 cm3	150 cm3	235 cm3
Capacitance
Anode, CA	53 mF		53 mF	53 mF	53 mF	53 mF
Cathode, CC	CC = CC′ × 2 π r h with CC′ = 17 mF cm−2	(9)	480 mF	960 mF	1280 mF	1600 mF
Cell, Ccell	${\left(\frac{1}{{\text{C}}_{\text{A}}}+\frac{1}{{\text{C}}_{{\text{C}}^{\prime }}\times 2\pi \mathit{rh}}\right)}^{-1}=$$={\left(\frac{1}{53}+\frac{1}{320\text{r}}\right)}^{-1}$	(10)	48 mF	50 mF	51 mF	51 mF
ESR
Anode resistance, RA	0.5 Ω		0.5 Ω	0.5 Ω	0.5 Ω	0.5 Ω
Cathode resistance, RC	$R_C=\frac{R_C^{\prime }}{2\pi \mathit{rh}}$, with RC′ = 140 Ω cm2	(11)	5	2.5	1.9	1.5
Cell, ESR	ESR = RA + RC = RA + $\frac{R_C^{\prime }}{2\pi \mathit{rh}}=$$=0.5+\frac{8}{r}$	(12)	5.5	3	2.4	2