12/12/2025
🍀Designing a night light using power from simple electrochemical batteries
-Dung Nguyen,
of STEM Club, Nguyen Trung Truc 1 High School, An Giang province
Recently, on 11th December 2025, the Chemistry-Biology Department of Nguyen Trung Truc 1 High School presented an exciting and beneficial STEM experiential activity with the theme: “Designing a Night Light Using Power from Simple Electrochemical Batteries.” This activity not only helps students explore Chemistry and Physics in greater depth through practical experiments, but also stimulates creative thinking, design skills, and the application of knowledge to real-life situations.
* From Theory to Practice: Understanding Electrochemical Batteries
The main content of the activity is Electrochemical Batteries, also known as Voltaic Batteries. Students are provided with fundamental knowledge about the operating principle of the battery: oxidation at the negative electrode (anode) and reduction at the positive electrode (cathode) create a flow of electrons, generating electrical energy. However, instead of using commercial batteries, the students got to try their hand at creating their own power sources using familiar, readily available materials. The student groups combined different metal electrode pairs, such as Copper (Cu), Zinc (Zn), Aluminum (Al), and common electrolytes like salt solution, citric acid solution (from lemons/limes), or even vinegar. This is where chemistry theory was literally "illuminated." Students directly observed and calculated how to connect these simple batteries into a complete circuit, generating enough voltage to power a small LED light. The difference in the standard electrode potential of the metals determined the voltage of each "homemade battery."
* Design Challenge: Creating a Night Light
The most exciting part of the experience was the challenge of designing and assembling a night light. Each group focused not only on generating electricity but also on ensuring the aesthetics and functionality of the final product.
- Circuit Calculation: Students had to carefully calculate how many "lemon batteries," "vinegar batteries," or "salt batteries" to connect in series to achieve the minimum voltage (approximately 1.5 – 3V) required for the LED light.
- Structural Design: Materials such as cardboard, recycled plastic bottles, wooden sticks, etc., were used to create the lamp frame. The designs were diverse, ranging from simple, whimsical shapes to more complex models, showcasing the creativity and ingenuity of the students.
- Presentation and Presentation: The completed product was presented by the groups, explaining the operating principle of the electrochemical battery used, the design process, and the feasibility of this "green" night light.
* The Spreading Significance of STEM
The activity was a resounding success, not only because of the unique nightlights powered by self-generated electricity, but also because of the values it brought:
- Connecting knowledge: Conveying chemical concepts (oxidation-reduction reactions) and physics concepts (electrical circuits, voltage) in a visual and easy-to-remember way.
- Encouraging critical thinking: Students had to experiment multiple times, adjusting materials, electrolyte concentrations, and connection methods to optimize battery performance.
- Promoting environmental awareness: The use of recycled and environmentally friendly materials to manufacture the battery and lamp frame contributed to educating students about sustainable development./.
