A New Design of the Air-Aluminum Battery, Optimized for STEM Activities

The air-aluminum battery is an excellent way to introduce students to numerous STEM related topics. In this work, we describe an improved design of the air-aluminum battery for STEM outreach activities. This hands-on activity consists of students creating electrochemical cells that each produce ∼0.9 V. Each cell consists of an aluminum foil anode, a sponge saturated with NaCl­(aq) as the electrolyte, and a small segment of graphite as the cathode. The entire assembly is secured using a 3d printed clip. The goal for the students during the activity is to assemble a battery capable of powering an LED. This activity is also designed as a team building exercise. The students must coordinate and work together to combine their electrochemical cells to power the LED. The total time of the activity, prelab through cleanup, ranges from 45 min to 1 h. We have held several variations of this activity, with groups ranging in size from 12 to 27 students working in teams of three or four.