The recent spontaneous combustion accidents of electric vehicles have once again caused the safety of new energy vehicles to attract high attention from the industry and outsiders. According to the data from the Defective Product Management Center of the State Administration of Market Supervision and Administration, as of the first half of this year, a total of 141 new energy vehicle recalls have been implemented in China, and the number of recalled vehicles is 860,500, many of which are related to power lithium-ion batteries; According to the new energy vehicle accident data, power lithium-ion battery failure is an important cause of fire accidents, accounting for up to 77%, of which battery cell thermal runaway accounts for 82% of power lithium-ion battery failure causes.
The reasons for the failure of power lithium-ion batteries are complex, including technical problems, design defects, material ratios, etc. Among them, manufacturing process defects in the production process are also important factors. Judging from the recall notice issued by Weimar Motors recently, it is important that the battery cell supplier mixed impurities during the production process, which caused abnormal lithium evolution in the power lithium-ion battery. In extreme cases, it may cause the battery cell to short circuit and cause the power lithium-ion battery to heat up. Out of control and risk of fire. Coincidentally, the BMW Group has recently recalled 26,700 plug-in hybrid vehicles globally. The reason is also due to the impurities mixed in the batteries during the production process.
Statistics show that 40% of battery accidents are caused by manufacturing defects. Among them, the common problems in the manufacturing process are due to poor management, lax control, and inadequate measures that lead to impurities such as metal dust being mixed into the battery, causing an internal short circuit to increase the battery temperature and cause spontaneous combustion. In addition, in recent years, power lithium-ion battery production companies have been pursuing higher energy density and charging and discharging performance, and upgrading these indicators requires stronger design and manufacturing capabilities, as well as higher standards and requirements in production processes. However, some companies have cut corners and shoddy materials when the design level, manufacturing process, and overall capacity are not reached. This will seriously affect the quality of power lithium-ion battery products and cause vehicle safety problems. It can be seen that to improve the safety of power lithium-ion batteries, we must pay attention to the manufacturing process.
To improve the production and manufacturing process of power lithium-ion battery companies, we must take multiple measures to improve management and strengthen quality control in all aspects. The first is to improve the infrastructure, improve the rules and regulations, use the system to manage production, and use a good quality management system to ensure the consistency of production of power lithium-ion battery products and ensure product quality. The manufacturing process of power lithium-ion batteries is, in the final analysis, a matter of grasping the technical standards. The company must establish clear quality indicators, yield targets, etc. Only clear objectives can lay the foundation for continuous improvement of product quality.
The second is to strictly implement the specifications, including the implementation of relevant standards and index parameters, and to prevent artificial arbitrariness. At the same time, it is necessary to consciously find loopholes in materials, production processes, operating procedures and other links, pick up the missing parts, eliminate various factors that are prone to product quality defects, effectively ensure product quality, and minimize safety risks. In the production process, irregular behavior must be eliminated. For example, the production environment is closely related to battery quality. Battery manufacturing must be a dust-free and static-free production workshop. The production site must have strict control measures to prevent metal dust from being introduced; various semi-finished products must be stored separately; material transportation tools must use magnets to eliminate metal dust, etc. . If the company does not strictly implement these regulations, it will lay a safety hazard for product quality.
The third is to vigorously carry out technological innovation. Power lithium-ion battery technology is constantly evolving. If you don’t strive to innovate, you will not be able to keep up with the pace of industry and market development. In addition to the overall technological innovation of the product, the manufacturing process of power lithium-ion batteries should also be continuously innovated. For example, some companies have introduced JTM (roll-to-module) technology to simplify the process and reduce the cost. The blade battery introduced by BYD is also a typical technological innovation and process innovation. These new technologies, new processes, and new methods, related to ensuring product quality, improving quality and brand influence, have greater boosting and supporting uses. At the same time, the company must also improve the level of automated production and improve the quality of power lithium-ion battery products with automated and intelligent production methods to ensure battery performance and battery safety.
The promotion of electric vehicles must take safety as the bottom line. As the core component of power lithium-ion battery, its safety is the lifeline of new energy vehicles. It is hoped that the company can learn from the spontaneous combustion accidents of electric vehicles, strengthen the manufacturing process management of power lithium-ion battery products, provide consumers and the society with safer and high-quality products, and eliminate people's safety anxiety about electric vehicles. Only in this way can electric vehicles gain the trust of consumers and truly embark on the road of marketization.
In order to accelerate the mass production of electric vehicles of different levels, platformization is essential. A car factory may have to produce dozens or even hundreds of different models in a short period of time, including pure electric vehicles, plug-in hybrid vehicles, 48V hybrid vehicles, 14V start-stop micro-hybrid vehicles, etc. Therefore, can it be maximized? Reuse and application platformization can win the race to accelerate time to market and reduce R&D costs.