Like Beijing, Shanghai, as a national leading demonstration city for the promotion of new energy vehicles, is also considering improving the service life of power batteries. Considering the current power battery quality assurance service standards of vehicle enterprises, power batteries can generally operate for 5 years and 100000 kilometers. How to break through the technical bottleneck and prolong the service life of the battery is a common topic faced by all battery manufacturers.
The bottleneck of electric vehicles lies in the battery. Only when the battery power problem is solved, other problems can be solved. Under the current technical conditions, changing the charging mode of power battery is a good choice to prolong the battery life. Industry insiders pointed out that the 8-year warranty publicized at present may not be realized. Due to the difference of production process in the production process of automobile power battery, there are some differences in the performance of battery cells in the battery pack. Over time, the monomer difference in the battery pack will gradually expand, which will eventually affect the performance of the battery and cause the rapid attenuation of battery performance. Different charging methods are important factors affecting the performance and service life of single lithium-ion battery. Appropriate charging methods can not only maximize the battery capacity, but also prolong the service life of the battery.
Long charging time and short driving range are the main reasons why electric vehicles are criticized. Although the large rate fast charging method solves the problem of long charging time, it seriously affects the service life of lithium battery. Blindly pursuing fast charging mode and large rate charging is prone to abnormal conditions such as high temperature and overcharge, and even lead to danger. Taking the "soft before strength" charging method, under the voltage and current that the battery can withstand, monitoring the environment, temperature and temperature difference, and actively maintaining the healthy state of the battery will help to prolong the service life of the battery and reduce the safety risk.
Charging mode is one of the ways to prolong battery life, but it is not a fundamental solution. The improvement of battery life and stability still needs to make a breakthrough in technology. In view of China's current situation, from the perspective of production technology, China's battery enterprises lag behind the world level in production and R & D capacity. The output of new energy vehicles reached 76000, a year-on-year increase of 2.5 times. A large number of gaps in the supporting power batteries of new energy vehicles, coupled with low barriers in the power battery industry, led to a large number of battery enterprises with low technical content put into production, resulting in overcapacity of domestic low-end batteries and blank market of high-end batteries. In addition, the energy density of batteries with low technical content is low, which affects the endurance mileage of new energy vehicles. If batteries with the same capacity are produced, the battery weight of China will exceed that of Japanese and Korean enterprises, which will affect the lightweight development of new energy vehicles.
In addition, there is a lack of unified production standards in China's battery industry. The universality of power batteries produced by various battery enterprises is very poor, which can not achieve standardized and large-scale production, which also increases the workload of battery design. Because there is no unified industry standard, the charging and discharging performance of batteries produced by various enterprises is very different. The upstream lacks standards and cannot be standardized, which directly leads to great differences in charging piles and becomes one of the reasons for the difficulty of charging. A unified battery standard will help standardize the battery industry, save human and material costs, and invest more resources in battery R & D and production process improvement.
On the one hand, the national support for electric vehicles continues to increase, and the power lithium battery is facing a rare development opportunity. On the other hand, due to battery life, safety and other obstacles, it has been unable to break through. Compared with international countries, China has many problems in the power battery of electric vehicles. On the one hand, the advanced materials and mechanisms in China are poorly studied, and the advanced technology of battery structure design is low. On the other hand, the automation level is relatively low, and the development capability of fine technology is also weak. Battery system is not just a combination of monomers. In fact, it is a very complex technology. In addition, the supply of high-end materials required for batteries is still insufficient, the consistency, yield, safety, reliability and product performance can not fully meet the market requirements, the overall innovation ability of enterprises is not strong, and the advantageous production capacity is insufficient.
