A primary battery is a device that can generate an electric current by a redox reaction, and can also be said to convert a chemical energy into electrical energy. Some primary batteries can constitute a reversible battery, and some primary batteries do not belong to a reversible battery. When the primary battery is discharged, the negative electrode undergoes an oxidation reaction, and the positive electrode undergoes a reduction reaction. For example, a copper-zinc primary battery, also known as a Daniel battery, has a positive electrode of a copper electrode and is immersed in a sulfuric acid solution; the negative electrode is a zinc plate and is immersed in a zinc sulfate solution. The two electrolyte solutions are connected by a salt bridge, and the two poles are connected by wires to form a primary battery. The dry battery used in normal times is made according to the original battery principle.
Test standard: GB 8897, IEC60086, etc.