2 Operational Theory | Model 3300PA |
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Micro-Fuel Cell is therefore a hybrid between a battery and a true fuel cell. (All of the reactants are stored externally in a true fuel cell.)
2.2.2 Anatomy of a Micro-Fuel Cell
The Micro-Fuel Cell is made of extremely inert plastic (which can be placed confidently in practically any environment or sample stream). It is effec- tively sealed, though one end is permeable to oxygen in the sample gas. At the permeable end a screen retains a diffusion membrane through which the oxygen passes into the cell. At the other end of the cell is a connector, and a temperature compensation network (resistors and thermistor) on a printed circuit board.
Refer to Figure 2-1, Basic Elements of a Micro-Fuel Cell, which illus- trates the following internal description.
Electrical Connector
C ircuit B oard
w ith tem perature com pensation network.
Anode
C athode
Teflon M embrane
Screen
C lam p
Figure 2-1. Basic Elements of a Micro-Fuel Cell (not to scale)
At the sensing end of the cell is a diffusion membrane, whose thickness is very accurately controlled. Near the diffusion membrane lies the oxygen sensing element—the cathode.
The anode structure is larger than the cathode. It is made of lead and is designed to maximize the amount of metal available for chemical reaction.
2-2 | Teledyne Analytical Instruments |