The simplest homemade battery
Channel: MEL Chemistry
Date: 2019-09-16

How can you assemble a simple battery at home? Check out the answer in this cool new video!
Equipment: copper and zinc plates, wires with clamps, phone charging wire, phone, multimeter, LED, plastic cups, 100g sodium chloride, 1L hot water.
Use crocodile clip wires to connect some copper and zinc plates. Prepare a table salt solution: dissolve 100g of salt in 1L of hot water. Pour the solution into cups and lower the “wired” plates into them. It is important that each cup contains both a zinc plate and a copper plate. When the circuit is closed, an electric current will run through it. You can verify this by connecting a multimeter to the circuit to figure out the voltage of the current in it. Try to power a diode – it glows! You can try to charge your phone with it by connecting your charger wire – it will charge, but not for long :) Now you know how to generate electric current during the apocalypse!
Chemical current sources are devices that convert chemical energy into electrical energy. The basis of chemical current sources is composed of two electrodes, a positively-charged anode, and a negatively-charged cathode, located in a solution that conducts electric current. In our battery, the zinc plates act as anodes, and the copper plates act as cathodes. When the circuit is closed, zinc is oxidized at the anode and free electrons are formed, which flow through the wires to the cathode, and are involved in the process of hydrogen reduction. These two redox reactions generate electric current:  
Zn - 2e = Zn2+
2H+ + 2e- = Н2
Safety precautions: perform this experiment only under adult supervision.