A voltaic pile battery. This type of battery was the first chemical battery and was invented by Alessandro Volta in 1791. This battery consists of two different metals. Here copper United States pennies manufactured before 1982 were used and the source of Zinc was zinc coated washers. Cotton paper is placed between the coins and wetted with an acid. In this experiment the acid used was 5% acetic acid from household vinegar. The vinegar is the electrolyte. Unlike the Leyden jar, the voltaic pile produces a continuous electricity and stable current. The order of the stack is copper, zinc and then paper. This pattern is repeated throughout the battery.