What is the reason for sparking when connecting the last wire in series with the battery?

[LailaLee]

Sparking occurs when the last wire in series with the battery is not properly connected; it needs to be securely connected to avoid sparking. More details about the battery are as follows: 1. Introduction: A battery, also known as an accumulator, is a type of cell that works by converting chemical energy into electrical energy. Typically, a battery refers to a lead-acid battery, which mainly uses lead and its oxides as electrodes and a sulfuric acid solution as the electrolyte. 2. Working Principle: A lead plate filled with spongy lead serves as the negative electrode, a lead plate filled with lead dioxide serves as the positive electrode, and a 22-28% dilute sulfuric acid solution is used as the electrolyte. During charging, electrical energy is converted into chemical energy, and during discharging, chemical energy is converted back into electrical energy. When the battery discharges, metallic lead acts as the negative electrode, undergoing oxidation and being converted into lead sulfate, while lead dioxide acts as the positive electrode, undergoing reduction and being converted into lead sulfate.