Lead-acid batteries are the earliest industrialized secondary batteries. They have a history of more than 150 years since they were invented in 1859, but the industry is still in the ascendant.
Lead-acid batteries are the batteries with the largest market share and the widest range of applications in chemical batteries, especially in applications such as starting and large-scale energy storage, and it is difficult to be replaced by other new batteries for a long time. The price of lead-acid batteries is relatively low, and they have comparative advantages such as mature technology, excellent high and low temperature performance, stability and reliability, high safety, and good resource reutilization. The market has obvious competitive advantages.
Compared with other battery metal materials, lead resources are relatively abundant. Lead reserves and regenerated lead ensure the sustainable development of the lead-acid battery industry for a relatively long period of time. Lead-acid batteries are widely used and will not cause a shortage of lead resources for a long time. The shortcomings of lead-acid batteries are: low energy density, short cycle life, the main raw material lead is a kind of toxic substance, there is a risk of lead pollution in the process of battery production and regenerated lead processing, and poor management may cause environmental and human health. harm.
With the breakthrough of new technologies and the application of new structures, the continuous advent of lead-carbon batteries, bipolar batteries, non-lead grid batteries and other advanced lead-acid batteries has changed the low mass-to-energy ratio and short cycle life. And with the gradual improvement of laws and regulations and the improvement of management level, the risk of lead pollution can also be prevented and controlled. It has injected new vitality into the sustainable development of the lead-acid battery industry. In the future, lead-acid batteries will still play an important role in applications such as backup power supply, energy storage, starting, and power. (1) Comparative advantages of lead-acid batteries
①Comparative performance advantage
At present, the large-scale industrialized secondary batteries mainly include lead-acid batteries, nickel-cadmium batteries, nickel-hydrogen batteries and lithium-ion batteries. Nickel-cadmium batteries contain the highly toxic element cadmium, which has been gradually replaced by other batteries. Currently, the most widely used batteries on the market are lead-acid batteries, lithium-ion batteries and nickel-hydrogen batteries.
Compared with other secondary batteries, lead-acid batteries have the following comparative advantages:
A. The battery with the longest time to realize industrialized production and the most mature technology has stable performance, reliability and good applicability;
B. Dilute sulfuric acid is used as electrolyte, which is non-flammable. The battery adopts normal pressure or low pressure design, which has good safety;
C. High working voltage and wide working temperature range, suitable for high-rate discharge applications such as hybrid electric vehicles (HEV);
D. It can be used for floating charging, with excellent shallow charge and shallow discharge performance, suitable for uninterruptible power supply (UPS), new energy storage, grid peak shaving and valley filling and other fields;
E. The large-capacity battery technology is mature and can be made into batteries of thousands of ampere hours, which provides convenience for large-scale energy storage.
②Comparative cost advantage
Lead-acid batteries are the cheapest secondary batteries, and the price per unit of energy is about 1/3 of that of lithium-ion batteries or nickel-hydrogen batteries. In addition, the main components of lead-acid batteries are lead and lead compounds. The lead content is as high as 60% of the total mass of the battery. The residual value of used batteries is relatively high, and the recycling price exceeds 30% of that of new batteries. Therefore, the overall cost of lead-acid batteries Lower.
③Comparative advantages of recycling
Lead-acid batteries are simple in composition, mature in regeneration technology, and have high recycling value. They are the easiest battery to be recycled and reused. The global production of recycled lead has surpassed the production of virgin lead. The recycling rate of lead-acid batteries in the United States has exceeded 98.5%, and the recycling rate of waste lead-acid batteries in my country has reached more than 90%. Nickel-cadmium batteries, nickel-hydrogen batteries, and lithium-ion batteries are mostly small batteries with complex composition, high regeneration costs, and difficulty in recycling. It is difficult for the recycling industry to achieve market-oriented operations. At present, the global average recycling rate of the aforementioned batteries is less than 20%, especially for lithium-ion batteries. Most countries have not yet achieved effective recycling and regeneration.
(2) Insufficiency of lead-acid batteries
①The energy density is low
Traditional lead-acid batteries have low mass and volume energy density. The energy density is only about 1/3 of that of lithium-ion batteries and about 1/2 of that of nickel-hydrogen batteries. They are also large in size and not suitable for light and small applications. use. In the future, the energy density of lead-acid batteries still has much room for improvement, especially for lead-acid batteries that use new materials and technologies such as foamed carbon. ②The cycle life is too short
The cycle life of traditional lead-acid batteries is short, and the theoretical cycle number is about 1/3 of lithium-ion batteries. There is still a lot of room for improvement in the cycle life of lead-acid batteries, especially lead-acid batteries with new materials, new structures and new technologies, such as bipolar lead-acid batteries and lead-carbon batteries.
③There is a risk of lead pollution in the industry chain
Lead is the main raw material for lead-acid batteries. Lead accounts for more than 60% of the battery quality. Lead-acid batteries worldwide account for more than 80% of the total lead consumption. Lead is a heavy metal, and the lead-acid battery manufacturing industry chain (including primary lead smelting, battery manufacturing, battery recycling, and recycled lead smelting) has a high risk of lead pollution. Poor management can cause environmental pollution and harm to human health.
4. Lead-acid batteries and environmental protection
Lead-acid battery manufacturing is the main industry that uses lead. The industry chain has lead pollution risks in primary lead smelting, battery production, waste battery recycling, and regenerated lead smelting. However, lead pollution in the entire industrial chain can be effectively controlled. Lead pollution prevention and control technology is relatively mature. There are already complete sets of technology and equipment related to smelting of primary and secondary lead in foreign countries. The domestic lead smelting technology is basically mature, including lead-acid battery manufacturing, as long as advanced environmental protection equipment is configured according to the specifications , The normal operation of environmental protection equipment will basically not cause lead pollution incidents. In the field of lead-acid battery manufacturing, advanced clean, automated, and mechanized production equipment, as well as advanced environmental protection technology and equipment, have been widely used, so that lead fumes, lead dust, lead compounds in water can be effectively treated, and lead pollution can be effectively controlled .
Advanced production processes include: one-fire multi-machine grid casting process, lead ingot cold cutting technology, automatic packaging and brushing, internal chemical forming process, etc. Advanced environmental protection processes include: high-efficiency pulsed lead dust processor, multi-stage wet lead smoke processor, alkaline mist spray acid mist processor, wastewater reclaimed water reuse system, etc. The frequent lead pollution incidents in my country in the past were mainly caused by inadequate relevant laws and regulations and policies and insufficient management in the whole process.
Mainly manifested in five aspects:
One is the disorderly competition between smelters, especially small smelters and illegal smelters, in order to compete for the market at low prices, adopt indigenous smelting methods, without environmental protection facilities or abnormal operation of the facilities; there are even some large smelters in order to reduce Cost, there is a phenomenon of non-standard environmental protection governance, resulting in the occurrence of pollution incidents in primary lead companies.
Second, there are a large number of small factories in the lead-acid battery manufacturing industry, and their production equipment is backward, unable to be equipped with complete and advanced environmental protection equipment and health protection facilities, which is not conducive to environmental protection and resource utilization.
Third, the recycling of lead-acid batteries is completely in a state of disorganized recycling, which is an important link that causes lead and acid pollution.
Fourth, a large number of waste batteries flow to small regenerated lead plants, and due to the out-of-control management of links, frequent environmental pollution incidents occur.
Fifth, there is a risk of cadmium pollution in power lead-acid batteries.