Interpreting battery system security from a supplier perspective

The China Electric Vehicle Hundred People's Summer Forum (2016) has come to an end. At the forum, experts in electric vehicles and related fields gathered to discuss the development of the electric vehicle industry around the technical innovation and safety guarantees of electric vehicles.

Huang Shilin, President of Ningde Times New Energy Technology Co., Ltd. made a speech at the forum.

The following is a record of the speech:

Today I want to understand how to understand the safety of this kind of electric vehicle from the perspective of a supplier of power batteries.

We believe that ensuring safety is fundamental to the development of the industry. From the development of CATL in recent years, we have been striving to become the most important supplier of power batteries in the world. For power batteries, the safety of power batteries is one of the most important factors in the safety of electric vehicles . From our point of view, after several years of hard work, we also have some perceptions, so share some of our understandings and some current practices with you.

For a product, we are now positioning the entire CATL market, that is, in the pure electric passenger car and light mix, we will take the three-way technical route. In the electric bus and energy storage, we will take the technical route of lithium iron phosphate. We also have deep cooperation with these customers of internationally famous brands. The safety characteristics of ternary materials and lithium iron phosphate are not the same. But the overall principle is basically the same.

First of all, the safety of the product in the whole life cycle, the safety depends on the entire product, from its birth, to its mission, and the safety of the whole life cycle.

First, from the perspective of safety concept, the safety of electric vehicle battery system is the combination of high pressure and chemical safety. Therefore, the combination of high voltage reliability and chemical safety creates a relatively large safety hazard. The middle includes chemical safety, high pressure safety, mechanical safety and functional safety. There are also many safety applications.

On the whole, we must ensure that such a product is safe in design. The entire CATL is pursuing zero accidents in pursuit of product safety, and it requires a system of overall safety design. For example, from the safety mechanism and prevention technology, from the global electric vehicle safety experience summary, as well as our in-depth analysis of failures, and finally to the summary of the entire standard and laws and regulations, we need to do some in-depth research and summary. Let it form a very good system for security design.

In a design process, we must clearly understand the objectives and safety and mechanism, and make the level of each layer clear, from the thermal runaway to the fire, explosion and other layers of the situation, all clear and safe design. All designs must be built around security.

We have a lot of batteries and modules in a battery pack. When a problem occurs, there is usually a problem with a single battery. We must absolutely guarantee its diffusion during the design process, and it will not spread or spread very slowly. The design concept is absolutely sufficient to pay attention to such a state when we design the battery system. This is an experiment, that is to say, we have a battery in the whole battery pack. I specially heated it to burn it. Look at our whole. Designed for some state of insulation isolation.

In the early stage, we emphasized the safety of the design, including the battery core, the module, and the safety of the design of the system and the safety certification of some products. Actually, there are still some things to be noticed, that is, the safety of the product application.

In terms of the safety of product application, what we are doing now is the remote monitoring system. This system has been running for more than a year in the Ningde era. At present, the effect is very good. When the terminal customer is using it, the battery can be collected in real time. The data of the system sends the data to the database in the headquarters through the transmission system. In this database, there is a complete set of core algorithms. After calculation, it is displayed on the platform of statistical monitoring and interacts with after-sales service.

When implementing the alarm, it can realize three-level alarm, which can find the problem very timely, and can also predict some problems, so that the problem of product safety can be reduced. With our entire after-sales service market, market traceability including future ladder utilization, we can Guarantee real-time monitoring and security maintenance throughout the lifecycle.

Seriously look at the safety problems of the entire power battery in the past period of time, some safety issues of construction and public exposure, we can see that there are charging problems, problems with the battery system itself, problems with users, although different The proportion of data sources will be a bit different, but it is probably divided into several aspects.

In the future, we will promote the data monitoring system. In addition to the design we have done, this data monitoring system is basically a passive form. We should be more proactive in ensuring the safety of electric vehicles. This initiative makes the entire electric car have a very good platform in use, and this platform is charging.

Any electric car must be charged during the process of use. The current charging only provides a charging service. This is not enough. The charging process should be turned into a process of testing the power battery system, that is, If I have the function of the power battery manufacturer's shipment test, the electric vehicle will charge a complete test every time it is charged, so that the safety protection and maintenance of the electric vehicle battery system can be fully realized. Detected behavior.

From our point of view, the current charging piles enhance some of the functions of the power battery test, the cost is not much increased, and the process can be relatively easy to implement, so we are implementing the system for monitoring and warning of the front battery operation. After one year of work, the next step is from the perspective of new energy in Ningde era. We will promote the work of charging equipment to improve the function of charging equipment into the detection and maintenance equipment of the power battery in the market, so that it can be greatly improved. The safety of our entire power battery in the market in the future.