Primary batteries and secondary batteries are one of the classification methods for battery classification, as well as classification according to battery shape and material, and so on.
What is a primary battery?
As the name suggests, the battery can only be used once. When the chemical energy in the battery is converted into electrical energy to provide electrical energy, the original electrical energy cannot be recharged or recharged in other ways. Therefore, it cannot be used again after being fully discharged. The electrochemical reaction of this battery is irreversible.
Generally, the common dry batteries, carbon-zinc batteries, alkaline batteries, mercury batteries, zinc-air batteries, etc. on the market all belong to this disposable battery. Different types of disposable batteries have different ways of use, but they are all limited to single use. In the manufacturing of many battery types, the raw materials used and the materials used in the manufacturing process are polluting and have a considerable impact on the environment and the human body.
What is a secondary battery?
Secondary batteries are reusable batteries that can be continuously charged and discharged. Secondary batteries are also converted into electrical energy through chemical energy, but they can be re-converted into chemical energy through charging, so that the battery can be reused. The number of uses varies depending on the material and design.
Commonly available on the market are lead-acid batteries, gel batteries, nickel-cadmium batteries, nickel-hydrogen batteries, lithium-ion batteries, lithium-ion polymer batteries, lithium iron phosphate batteries, and so on. Different types of secondary batteries have different uses because of their rated voltage, rated capacity, operating temperature, and safety. In the manufacturing of many battery types, the raw materials used and the materials used in the manufacturing process are polluting and have a considerable impact on the environment and the human body.
The difference between primary battery and secondary battery
What is the difference between a primary battery and a secondary battery? The most obvious difference can be seen from the words: "primary" and "secondary", that is to say, a primary battery can only be used once, and the battery will be gone after the charge is exhausted. The battery is recycled many times, and it can be used again when the battery is fully charged. The common differences are as follows:
1. From the structural point of view, during the discharge process of the secondary battery, reversible changes occur between the electrode volume and the structure, while the interior of the primary battery is much simpler, because these reversible changes do not need to be adjusted.
2. The mass specific capacity and volume specific capacity of primary batteries are larger than ordinary rechargeable batteries, but the internal resistance is much larger than that of secondary batteries, so the load capacity is low.
3. The self-discharge of the primary battery is much smaller than that of the secondary battery. A battery can only be discharged once, for example, alkaline batteries and carbon batteries belong to this category, and secondary batteries can be recycled repeatedly.
4. The secondary battery is more environmentally friendly than the primary battery. The primary battery must be discarded after use, and the rechargeable battery can be reused. The next-generation rechargeable battery that meets the national standard can usually be reused more than 1,000 times, which means that the waste generated by the rechargeable battery is less than 1/1000 of the original battery. Whether in terms of waste reduction, resource utilization or economy, the advantages of secondary batteries are very obvious.
5. The internal resistance of the primary battery is much greater than that of the secondary battery, but its high-current discharge performance is not as good as that of the secondary battery.
6. In the case of low current and intermittent discharge, the mass specific capacity of the primary battery is greater than that of the ordinary secondary battery, but when the discharge current is greater than 800mAh, the capacity advantage of the primary battery will be significantly reduced.