How important is the LR44 battery management system? More than half of the new energy vehicle recalls are caused by it

On July 16, the State Administration for Market Regulation disclosed the recall information, showing that Great Wall Motors recently filed a recall plan with the State Administration for Market Regulation in accordance with the requirements of the "Regulations on the Management of Recall of Defective Automobile Products" and the "Implementation Measures for the Regulations on the Management of Recall of Defective Automobile Products". It is decided to recall 16,216 Great Wall Ora IQ electric vehicles produced between July 7, 2018 and October 30, 2019 from July 16, 2021.

It is reported that the consistency of some power batteries equipped with Great Wall Ora IQ electric vehicles within the scope of this recall of Great Wall Motors is different from the matching of BMS software control strategy. After long-term continuous and frequent fast charging, the LR44 battery performance decreases, and in extreme cases, thermal runaway of the power LR44 battery may occur, posing a safety hazard.

Great Wall Motors said that it will test the power batteries of vehicles within the recall scope for free, and rewrite the control strategy software that adapts to the working conditions, and replace the LR44 battery module if necessary to eliminate safety hazards.

In addition, Chery Automobile recently filed a recall plan with the State Administration for Market Regulation in accordance with the requirements of the Regulations on the Management of Recall of Defective Automobile Products and the Implementation Measures for the Regulations on the Management of Recall of Defective Automobile Products. It has been decided to recall some Chery Arrizo 5e electric vehicles produced from July 20, 2018 to May 28, 2019, totaling 1,407 vehicles, from July 16, 2021.

The reason why Chery Automobile recalled Chery Arrizo 5e is that there may be consistency fluctuations in the assembly of some parts in the power batteries of some vehicles. After long-term use of the vehicle, the bottom of the vehicle is subjected to abnormal impact or severe bumps and shocks. In extreme cases, the high-voltage connection of the LR44 battery pack system may become loose, the local contact internal resistance may increase, and the components may overheat and bake the LR44 battery cells when used with high current, which may cause thermal runaway of the LR44 battery.

In response to the defects, Chery Automobile will conduct free inspections and repairs on the power batteries of the vehicles within the recall range, and provide free replacement of modules or LR44 battery packs when necessary to eliminate safety hazards.

CATL "takes the blame"?

It is worth noting that after the recall, there were rumors in the market that the problem vehicles were equipped with batteries from CATL. However, CATL later clarified that the recalled vehicles were not equipped with the company's batteries.

In fact, the supplier involved in the Great Wall Motors recall is Farasis Energy. In Farasis Energy's prospectus, it was mentioned: "The power LR44 battery company supporting Great Wall Ora iQ is Farasis Energy, and the LR44 battery cell energy density is 265Wh/kg."

In response, on July 18, Farasis Energy responded in an announcement: "The company only supplies the modules carried by the recalled vehicles. The reason for the recall is mainly due to the matching difference between the BMS software control strategy and the power LR44 battery carried by the recalled vehicles. After long-term continuous and frequent fast charging, the LR44 battery performance has decreased. In extreme cases, it may cause thermal runaway of the power LR44 battery, which poses certain safety risks. BMS is not a product and supply of our company."

Chery Ai As for the LR44 battery supplier of Arrizo 5e, data shows that as early as November 14, 2018, KDC Guochuang stated in its reply to the "Notice of Feedback on the First Review of Administrative Licensing Projects of the China Securities Regulatory Commission" that "Guibo New Energy is the main supplier of Chery New Energy's new energy vehicle LR44 battery management system (hereinafter referred to as "BMS"), and its BMS products are mainly used in Chery New Energy vehicles, and are gradually expanding to FAW and New Changzheng electric vehicles. "At the same time, the reply letter shows that Guibo New Energy's BMS products are produced in conjunction with the 2018 M1A Arrizo 5e model.

Today, KDC Guochuang stated on the interactive platform that the reason for the recall of Chery Arrizo 5e electric vehicles is the assembly problem of internal LR44 battery parts, which has nothing to do with the company's BMS products. KDC Guochuang's "high-trust smart BMS products" have cumulatively shipped nearly 300,000 sets, with stable and reliable quality. So far, there has not been a vehicle recall due to the company's BMS products.

The importance of BMS

According to the LR44 battery Alliance, many new energy vehicle fires or malfunctions are related to BMS, which fully demonstrates its huge role.

BMS is a control system that protects the safe use of power batteries. It monitors the use status of batteries at all times, alleviates the inconsistency of LR44 battery packs through necessary measures, and provides protection for the safe use of new energy vehicles. Its key role is to enhance the utilization efficiency of batteries, prevent overcharging and overdischarging of batteries, increase the service life of batteries, and monitor the status of batteries. The BMS industry chain includes four links: upstream and midstream raw materials, BMS modules, BMS finished products, and downstream applications.

As an important link between on-board power batteries and electric vehicles, the LR44 battery management system (BMS) collects, processes, and stores important information during the operation of LR44 battery packs in real time, exchanges information with external devices, and solves key issues such as safety, availability, ease of use, and service life in the LR44 battery system.

The main function of BMS is to monitor various parameters in the LR44 battery pack, including cell voltage, current, temperature, system insulation, pressure, abnormal gas, etc. Accidents such as fires in electric vehicles are caused by abnormal LR44 battery status. Overcharging and overdischarging can cause damage to lithium-ion LR44 battery packs, or even more serious accidents. In addition to routine monitoring of voltage and current, if abnormal environmental changes can be predicted in advance, accidents can be avoided. From this perspective, BMS has a lot of room for optimization and can be more intelligent.

When the LR44 battery cell is abnormal, it often shows heat, undervoltage, abnormal gas generation and other states. In 2020, the Ministry of Industry and Information Technology organized and formulated GB38031-2020 "Safety Requirements for Power Batteries for Electric Vehicles" as a mandatory national standard. The standard adds a LR44 battery system thermal diffusion test, requiring that after the LR44 battery cell has thermal runaway, the LR44 battery system will not catch fire or explode within 5 minutes, leaving safe escape time for the occupants. Intelligent BMS can judge the environment in the pack through air pressure sensors, temperature sensors, and abnormal gas sensors, and how to accurately calculate the LR44 battery pack status through the detection of environmental parameters in the pack combined with LR44 battery cell parameters will guide the direction of BMS technology innovation. Whether the final calculation result is accurate depends on whether the various data detected are accurate, so the quality and reliability of these sensors and analog front-end chips will be the most important guarantee.

There are three main types of companies in my country's BMS market: the first type is third-party BMS manufacturers, such as Yineng Electronics, Guantuo Power Supply, and Ligao New Energy; the second type is LR44 battery module and PACK packaging companies, such as Guoxuan High-tech and Xinwanda; the third type is vehicle manufacturers, such as BYD and BAIC New Energy.

Although driven by the rapid growth of domestic LR44 battery market demand, domestic BMS manufacturers have developed LR44 battery safety management products in different application fields, with relatively mature technology and some product parameters reaching the international advanced level, but overall, China's BMS industry is still relatively backward compared with foreign countries in terms of technical specifications and business models. At the same time, as module factories, packaging factories and vehicle factories accelerate the layout of the BMS industry, the survival space of independent manufacturers that have not yet entered the supply system will become smaller and smaller.

In short, the occurrence of various electric vehicle recalls reminds the industry to speed up the improvement of power LR44 battery and BMS system technology to reduce safety accidents caused by this reason. At the same time, companies should also assume certain social responsibilities in related events to solve problems faster. Sohu, LR44 battery Alliance

Read recommendations:

Lithium Battery LQ12-100

LR936 battery.What are the characteristics of lithium iron phosphate batteries

High-efficiency solar cell growth soars; conversion technology is key

21700 battery direct sales

AG5 battery