LS Electric Develops 'BTS' to Fundamentally Prevent ESS Fires

LS Electric's BTS (Battery Temperature Sensing) for Preventing Energy Storage System (ESS) Fires

[Photo by LS Electric]

[Asia Economy Reporter Ki-min Lee] A solution that can fundamentally prevent battery overheating, one of the causes of energy storage system (ESS) fires, has been developed.

LS Electric recently announced on the 28th that it has developed BTS (Battery Temperature Sensing), which uses optical technology to measure temperature in real-time down to the battery cell level and stops ESS operation if overheating exceeds a certain threshold.

ESS battery manufacturers have been expanding temperature information provision from the rack stage, which is the finished product stage, to the more detailed module stage recently. However, when temperatures exceed a certain level, damage to racks and modules is inevitable, limiting the ability to clearly identify the cause of overheating. According to studies related to ESS fires, lithium-ion batteries generally begin to experience performance issues around 40℃, enter the “swelling” stage when exceeding 60℃, and emit gas at temperatures above 150℃, which can lead to ignition if sustained for more than 30 minutes. Once a battery enters the swelling stage, it is mechanically damaged and cannot be reused.

◆ BTS Measures Temperature at Cell Level and Stops Equipment Operation During Overheating... Reduces Fire Risk and Equipment Replacement Burden

The BTS developed by LS Electric inserts specially designed optical fibers that do not interfere with electrical and electronic devices to measure continuous temperature at 30cm intervals at the cell level that makes up the module. LS Electric explained that this allows for more precise and faster monitoring of overheating zones.

BTS starts monitoring based on the optimal operating temperature of 25℃ for normal battery operation and issues ‘alarm’ and ‘danger’ warnings just before 40℃ when abnormal signs appear. It then forcibly stops the operating system to prevent fires caused by overheating as well as damage to battery modules and cells. Additionally, by analyzing the three-dimensional temperature distribution of the battery module, it can accurately identify the actual overheating point, allowing re-overheating to be prevented by replacing only the affected cells, significantly reducing the burden of equipment replacement.

LS Electric also provides a service where, if customers wish, cooling and air conditioning systems can be remotely activated immediately upon ESS shutdown due to battery overheating, enabling rapid resumption of operation by detecting even slight temperature changes for efficient ESS operation.

Furthermore, when BTS is installed, it can instantly detect overheating at specific points, allowing operation at about 90% output as before. Excessive charging and discharging causing temperature rise is one of the causes of ESS fires, and following repeated fire incidents, the government has recommended limiting battery output to below 80%. Since the optical fiber is inserted and connected via communication, installation is also simple.

LS Electric has already installed BTS at its Cheongju plant ESS in July for demonstration operation, and in mid-this month, held a seminar inviting officials from Korea Electric Power Corporation, KEPCO KPS, KEPCO KDN, and the Energy Agency to explain the technology and actual operation results at the BTS installation site.

An LS Electric official said, “Although there have been no fire incidents at ESS sites we have contracted so far, the ESS market is rapidly shrinking due to repeated accidents. We developed a solution that can fundamentally prevent ignition caused by equipment temperature rise,” adding, “We hope this technology, which maximizes user benefits through equipment protection and efficient operation, will be widely expanded and serve as an opportunity to revitalize the entire market.”