Hyundai, Kia unveil tech for battery management system

An infographic for a battery management system / Courtesy of Hyundai Motor Group

Hyundai Motor and Kia unveiled a number of technologies for their battery management system (BMS) to ensure customers of the safety of electric vehicles (EVs), following a recent EV fire that burned over 100 vehicles at a parking garage in Incheon.

In a press release Thursday, Hyundai Motor and Kia said they are making extensive safety efforts across hardware and software to enhance the fundamental aspects of EVs, stressing their BMS is the essence of 15 years of technological experience and R&D efforts.

The BMS serves as the brain of a vehicle battery, taking charge of overall management and protection of the battery as well as providing the necessary information for controlling its use.

Hyundai Motor and Kia said they established the technological basis of the BMS through years of experience in developing hybrid vehicles and maintaining a technological lead on their competitors by developing a variety of advanced technologies, such as multi-fast charging systems and vehicle-to-load, before other carmakers.

One of the key functions of the BMS is precise monitoring of a battery system, ensuring the battery operates safely and efficiently. The companies said their BMS monitors various factors, including voltage deviations, insulation resistance, current and voltage changes, temperature and overvoltage or undervoltage conditions.

When the BMS detects any malfunctions, it immediately assesses the risk level and initiates vehicle safety control measures. The abnormal data is transmitted to remote support centers of the carmakers, which then automatically send a text message to the customer.

Recent vehicle models are also equipped with a feature that can detect instant and micro short circuit situations, which can help the system to identify potential defects days or even weeks before they become serious. Hyundai and Kia said they believe this feature will help prevent battery-related fires, and that they will apply it to new EVs and other vehicles already on the road by the end of this year.

Firefighters demonstrate how to extinguish a fire in an electric vehicle at Busan Fire & Disaster Headquarters in Busan's Yeonje District, Wednesday. Yonhap

The carmakers also rebuffed growing speculation that overcharged batteries may cause a fire, noting that there have been no cases of fires caused by overcharged batteries in Hyundai and Kia EVs.

"The BMS focuses on monitoring the charging state and maintains close coordination with charging controllers, effectively preventing overcharging," an official at Hyundai said. "As a result, the likelihood of issues caused by overcharging is close to zero percent."

Hyundai and Kia noted that BMS first ensures that the charging controller manages the optimal charging current to make sure the battery gets charged within a safe range. The BMS also monitors the battery's charging status in real time and terminates charging immediately in case of any deviation from the normal range. In case both the controlling system of the vehicle and the battery pack fail, a physical safety circuit is activated to shut off the switch.

"Hyundai Motor Group's EVs incorporate a comprehensive range of safety technologies developed based on the expertise and experience accumulated so far," the official said. "We are committed to ensuring that customers worldwide can feel safe driving our EVs."