Fuel Cell is an electrochemical devices that puts out electric current due to a chemical reaction that result in many free electrons (negative charges). An old invention that first used in NASA space explorations- today you may find them in automobiles.
Now, if you take this fuel cell and miniaturize it in tiny cell that capable of generating micro amps but linearly proportional to its fuel consumption, then you end up with a tiny battery the fueled by alcohol present in your breath.
Inside the cell there exist a layer of platinum that acts as a excellent catalyst for breaking down ethyl alcohol into water, carbon dioxide and some free electrons. These free electrons, also called negative charges, travel out on the wires in the form of electricity. The amount of alcohol in one's breath will always be proportional to the amount of electricity the fuel cell outputs.
One of the most advanced techniques for determining intoxication is fuel cell technology. The AL9000 fuel cell breathalyzer is the gold standard in portable testing via breathalyzer. This type of device is preferred by peace officers and other law enforcement officials because it provides a high level of accuracy. Most of the breathalyzers on the market that are offered for consumer use utilize semi-conductor based designs that detect and measure alcohol in the breath of the subject. This technique is not as accurate as the AL9000 and the results achieved using many of the AL9000’s competition are subject to false positives and contamination.
The AL0000’s fuel cell technology measures the content of alcohol within your breath by catalyzing platinum metal with a chemical reaction. During this reaction, the ethanol that is present in the subject’s breath is oxidized to acetic acid at the anode and the overall reaction produces acetic acid and water alongside an electric current. The current is measured. The measurement of the current is utilized to calculate the BAC. Fuel cell breathalyzers are more specific for the ethyl in alcohol and less prone to get a false reading from substances that are similar in their chemical makeup to alcohol, like ketones, for example. The AL9000’s results are accurate and reliable.