In 1859, French chemist GastonPlante discovered the significance of the chemical reaction on the surface of the lead electrode during charging and discharging of lead-acid batteries. After more than 150 years of development and improvement, lead-acid batteries have become a class of high safety, low manufacturing costs, and stable voltage characteristics. , Long service life, wide range of applications, abundant raw materials and low cost, "resource recycling" products that can be recycled at low cost. With the development and utilization of natural energy such as solar energy, wind energy, geothermal energy, tidal energy, and the development of the electric vehicle industry, lead-acid batteries, as a "green" industry that does not consume the earth's resources, will face a broader development space and become a society Energy products that are indispensable in production and business activities and mankind.
1. Performance advantages of lead-acid batteries
The main performance advantages of lead-acid batteries are reflected in several aspects: the longest industrialized production time, the most mature technology, stable and reliable performance, and a wide range of applications; use dilute sulfuric acid as the electrolyte, no flammability, and the battery adopts normal pressure or Low-voltage design, good safety; high working voltage, good power characteristics, wide operating temperature range, suitable for high-rate discharge applications such as HEV; can be used for floating charge, shallow charge and shallow discharge performance, no memory effect, suitable for UPS, Renewable energy storage and other fields; large and small battery technologies are mature and can be made into batteries of various specifications below the ampere-hour level and thousands of ampere-hours.
2. Market structure and technology status of lead-acid batteries for electric vehicles in China
According to relevant statistics, the global average annual growth rate of batteries is less than 5%, while the annual growth rate of the total number of batteries in China has reached 9.4%. In particular, lead-acid batteries are developing rapidly, with an annual growth rate of more than 30%. China's lead-acid battery market is dominated by car batteries, accounting for about 70% of the total, with an average annual growth rate of 17% in the past five years. Due to the continuous advent of new high-power lead-acid batteries, the continuous improvement of the quality level and the low-cost advantages, the development of electric bicycles and electric motorcycles as transportation tools in underdeveloped countries and fitness tools in developed countries is amazing. China's output has nearly doubled every year. The rate of growth is up to 50% annually.
China's battery industry has entered a period of rapid development. After technological transformation and equipment updates, the industry's technical level has been greatly improved. The quality of most products is basically at the same level as that of similar international products. Through technological improvement, traditional batteries are developing towards new technologies such as sealing, maintenance-free, and colloids. In particular, the deep-cycle power battery manufacturing technology represented by my country's independent innovative product electric bicycle battery even surpasses advanced industrial countries such as Europe, America, Japan and South Korea, and is at the leading level.
In recent years, new domestic lead-acid batteries have been continuously launched. Tubular electrode colloidal lead-acid batteries have been used in batches for energy storage and low-speed pure electric vehicles, and their service life and reliability have been greatly improved. The improved AGM lead-acid batteries have been used in batches in addition to low-speed pure electric vehicles. Road tests on a variety of light and micro-hybrid HEVs; Jiangsu Shuangdeng Group has mass-produced wound lead-acid batteries through independent research and development technology and imported foreign equipment. In addition to being applied to various large-scale engineering vehicles, it has also been It is applied to a variety of domestic or joint venture brands of light hybrid HEV, the model is 6-SPB-50 TART/STOP (start-stop technology) wound lead battery for micro-hybrid vehicles, the discharge current is 300A, when the discharge is 1.0s The starting life has reached 110,000 times, which is much higher than the level of 20,000 times of ordinary AGM batteries.
3. New technology of foreign lead-acid batteries
1) The HEV special ceramic diaphragm bipolar lead-acid battery jointly developed by Sweden OPTIMA and VOLVO is a new breakthrough in lead-acid batteries. The battery adopts a bipolar structure and ceramic diaphragm. Compared with traditional lead-acid batteries, it uses 50% less lead and 20% weight. It has a long cycle life, safe and maintenance-free, high charging and discharging efficiency, low price, and easy recycling. Features.
2) The 36V/8Ah bipolar ear wound valve-regulated lead-acid battery pack developed by Hawker Company of the United States. The battery uses a variety of new processes such as rolling thin plate (0.4mm), non-curing internal chemical city, high assembly pressure, etc. , 8Ah battery can discharge at a high rate of 250A, its specific power and other performance have reached the level of nickel-hydrogen battery, and the cost is less than 1/2 of nickel-hydrogen battery.
3) The foam graphite lead-acid battery (also known as FF 3-dimensional battery) developed by Firefly Energy, a subsidiary of NASA, improves the specific energy (up to 70Wh/kg) and power characteristics (up to 800~1000Wh/kg) of the battery; improves the battery The cycle performance and high and low temperature performance; lead 50%~70% less than ordinary lead batteries.
4) The super battery produced by EastPann in the United States has been used in HondaCivic's medium-hybrid HEV. The application results show that the super battery can completely replace MH-Ni and other batteries for HEV, and has better operating performance than MH-Ni batteries. The cost reduction is more conducive to the recycling of used batteries.
5) The secondary colloidal electrolyte design of lead-acid batteries for electric vehicles of German Sunshine Company has been tested. The expected life of its 6V, 160A.h battery can reach 4 years. It has the advantages of large heat capacity and small temperature rise.
4. Development trend
In the field of electric vehicle batteries in the future, due to the low cost and mature promotion technology of lead-acid batteries, the opportunity should not be underestimated. It is one of the choices to realize the promotion of new energy vehicles as soon as possible. In 2010, US President Barack Obama announced to the outside world a US$2.4 billion support for 48 The project is to develop the development and production of next-generation batteries and electric vehicles, which includes a project of 66.8 million US dollars to support lead-acid batteries. About half of this fund is used to research lead-carbon electrode technology to produce advanced lead-acid batteries, and the other half is used to support production "Super battery" based on lead-acid batteries. In my country's "Twelfth Five-Year Plan" proposal, new energy vehicles are listed among the seven strategic emerging industries that the country will focus on fostering and developing in the next five years. According to forecasts by international authoritative organizations, the market imagination of self-use storage batteries is about 100 billion yuan or more, which will surely usher in the peak of lead-acid storage batteries.
In recent years, new types of lead storage batteries such as wound, bipolar, graphite foam, and super batteries have been launched or industrialized in developed countries, and have been used in dozens of models such as Toyota Pruise, Honda Insight and Suzuki TwinHEV in Japan, and LupoHEV in Germany. Application. According to analysis by Mr. Alex Molinaroli, President of Johnson Controls Energy Power, car start-stop technology (micro-hybrid car) is the most economical choice for consumers. The most ideal power source for this car is lead-acid batteries. The global market demand will reach 35 million in 2015. set.
With the application of new technology of lead-acid batteries, and every car and battery car are using lead-acid batteries, the application of new technology of lead-acid batteries in electric vehicles has a significant comparative advantage and a broad market prospect.