|MadSci Network: Engineering|
Thanks for your question,
As you may know CO is a product of incomplete combustion. For any combustion there must be 3 pieces to the puzzle. The first is a fuel source. Depending on the circumstances fuel can be anything from petrol to coal, from paper to your Dad's backyard shed. The second piece is oxygen. In the vast majority of cases this is in the air surrounding the fuel. The third piece of the puzzle is a heat source for ignition. This may be a lighter, a stray spark or a hot iron left on the ironing board. When all these components are present the combustion formula is as follows:
Fuel (Eg. Propane) + Oxygen ---> Carbon Dioxide + Water
C3H8 + 5O2 ---> 3CO2 + 4H2O
Where there is insufficient oxygen some of the CO2 becomes CO. Without knowing the specifics of your situation I would be curious about your measured rates of CO.
1) I'm not sure you have a source of fuel (unless you're melting the battery casings)
2) You obviously have oxygen
3) You probably have a heat source where your batteries are connected and/or the casings if they are heating up.
Basically, you'll need to find a source of heat and determine any substances it is heating up. Determine heat source and fuel and you'll find your, obviously incomplete, combustion and therefore the source of your CO.
On their own batteries should not produce CO. It is for this reason that the car industry is pushing for H2 cars. Their only emissions are heat and H2O.
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