Kit scientifique pour les enfants

Le kit scientifique sur les piles à combustible en eau salée illustre un concept de pile à combustible de pointe : combiner un électrolyte d'eau salée avec des plaques de magnésium pour générer de l'énergie électrique. Le kit de pile à combustible à eau salée vous permet d'étudier la science derrière la technologie des piles à combustible à eau salée, soit en alimentant la mini-turbine incluse, soit en créant vos propres applications électriques.

• Comprend un dispositif d'alimentation à pile à combustible à eau salée et au magnésium
• Développez vos propres applications de micro-piles à combustible
• Facile à intégrer et à utiliser
• Compatible avec d'autres kits scientifiques Horizon

What is a salt water fuel cell? How does it work?

This kind of fuel cell works with air and with a plate made with magnesium. The electricity is made by two chemical reactions which occur in two different point of the cell. The first sight of the reaction is on the plate which is called anode. On this side, the water reacts with the magnesium and creates hydrogen ions (protons) and magnesium hydroxide and generates two free electrons. On the other part of the cell (cathode), the oxygen contained in the air which pass through the cell walls react with the water in order to constitute hydroxide ions. This reaction is possible only if there are additional electrons which are provided. So during the reaction, the free protons generated on the anode are attracted by the cathode because of the difference of potential. If the cell is linked to an electrical circuit, the free electrons will pass inside it in order to reach the cathode and let the second reaction happen. You can find the two half redox equations below.

Mg + 2H2O → Mg(OH)2 + 2H + 2e-

1/2 O2 + H2O + 2e- → 2OH

2Mg + O2 + H2O → Mg(OH)2

The salt in the water is used as a catalyst. In other words, it means that salt accelerate the reaction between Mg and water.