The Battery Safety Electrolyte Sensor (BES) and Battery Safety Electrolyte Detector (BES LITE) aim to improve lithium-ion battery safety.
Honeywell recently released its next generation of battery safety sensors to improve safety in lithium-ion battery applications. The Battery Safety Electrolyte Sensor (BES) is designed specifically for on-road applications, and the Battery Safety Electrolyte Detector (BES LITE) is designed for sealed portable lithium-ion battery packs in non-automotive applications.
In light of the ongoing energy transition, on-road vehicles and heavy-duty equipment are increasingly dependent on lithium-ion batteries. While these batteries play a crucial role in powering the future, they are not without risks, particularly when exposed to thermal, electrical, or mechanical stresses, including manufacturing defects. Fires in lithium-ion batteries are primarily caused by thermal runaway — a process where the battery’s temperature increases in a self-accelerating cycle, ultimately leading to fires and explosions. This can occur due to factors such as overcharging or internal short circuits, where the separator melts, causing initial heat generation. As the temperature rises, the electrolyte vaporizes, releasing hazardous vapors. If no countermeasures are taken, the degrading battery enters the thermal runaway phase, resulting in catastrophic fires or explosions.
The BES series addresses these safety concerns by using Honeywell’s proprietary Li-ion Tamer electrolyte gas detection technology to identify “first vent” events. These events serve as early warning signs of potential battery malfunctions, enabling the system to issue alerts five to 20 minutes prior to a risk of fire. Such early detection is vital for ensuring both vehicle safety and the well-being of passengers and drivers alike. They also detect multiple gases released during thermal runaway, which minimizes the risk of false negatives. Its uncomplicated integration process is facilitated by a rate-of-change algorithm, eliminating the need for meticulous target gas threshold testing.
The sensors are equipped with dual operating modes and can be switched between ECO Mode and NORMAL Mode via CAN commands. In ECO Mode, power consumption is significantly reduced by 60%, as CAN communication is disabled. However, it automatically reverts to NORMAL Mode to send alarm signals to the Battery Management System (BMS) in the event of an alarm condition. In NORMAL Mode, the sensor operates at full functionality with active CAN communication.
Honeywell also released BES LITE to address needs in other non-automotive sectors and applications, such as battery energy storage systems (BESS), urban air mobility (UAM), unmanned aerial vehicles (UAV), electric two-wheelers, three-wheelers, and portable battery applications. Recent incidents of battery fires in these applications have led to significant negative publicity for respective OEMs and resulted in considerable asset damage and increased liability claims.
Like BES, the BES LITE sensor is low-profile and lightweight, using Honeywell proprietary gas sensing technology to selectively detect battery electrolyte vapor. It is designed to detect gases that are typically released during the initial phase of thermal runaway as well as throughout the entire thermal runaway process. This detection capability facilitates the prompt identification of imminent dangers or risks, significantly enhancing safety measures in critical situations and allowing for proactive responses that can prevent the loss of assets and protect lives. Early detection may vary based on factors such as the nature of cell abuse and its severity, state of charge, and other variables.
The BES LITE sensor is highly resistant to siloxane poisoning and selectively responds to only battery electrolyte vapors. This enables asset protection by providing early and reliable detection of battery electrolyte vapors without false alarms, making it suitable for critical applications and environments. It also allows compliance with international regulations and guidance by providing a deterministic detection of thermal runaway events.
Honeywell
automation.honeywell.com
