In a significant advancement for autonomous driving and electric vehicle safety, researchers at the Harbin Institute of Technology have developed a multifunctional frequency modulated continuous wave (FMCW) LiDAR system that can simultaneously perform high-precision 3D imaging and multi-parameter sensing. The new technology, described in a paper published in Light: Science & Applications (DOI: 10.37188/lam.2026.102), allows for the measurement of environmental temperature, gas concentrations, and liquid density alongside traditional 3D mapping.
The innovation addresses a critical limitation of conventional FMCW LiDAR, which is widely used in autonomous vehicles for its high-resolution imaging capabilities but cannot detect internal battery states or environmental parameters. Thermal runaway in batteries is a major safety concern for electric vehicles, and early warning systems depend on monitoring multiple parameters such as temperature, electrolyte density, and characteristic gases. Currently, these functions require separate systems, leading to increased complexity, cost, and integration challenges. The new multifunctional LiDAR aims to consolidate these capabilities into a single device.
By detecting echo signals from both free space and optical fiber, the system achieves 3D imaging while simultaneously sensing physical parameters. In proof-of-concept experiments, the team successfully imaged a target at 30 meters with adjustable resolution from 0.3 cm to 1.2 cm. They also measured the electrolyte density and temperature of a battery with accuracies of 3×10⁻⁵ g/mL and 0.5 °C, respectively. Moreover, the system detected concentrations of gases critical for monitoring thermal runaway—C2H2, CO2, and CH4—with detection limits of 0.07 ppm, 48 ppm, and 0.56 ppm, respectively.
Professor Yongkang Dong, who led the research, explained that the technique moves FMCW LiDAR technology from free space into optical fibers, realizing an optical frequency domain reflectometry (OFDR) that is used for sensing. OFDR shares the same positioning principle as FMCW and offers high spatial resolution and large dynamic range, making it suitable for measuring strain, temperature, pressure, and gas concentration.
The scientists demonstrated the system's capabilities by imaging a plastic plate with a "HIT" symbol placed 30 meters away, while simultaneously monitoring a sulfuric acid solution (as a battery electrolyte) and a multi-pass cell filled with mixed gases. The distance to the target was calculated from the optical path difference between reflection peaks, and the reflection spectra of various sensors were demodulated from their spatial domain peaks.
The implications for the automotive industry are substantial. This multifunctional LiDAR could replace multiple separate systems in electric vehicles, reducing complexity and cost while enhancing safety. By enabling real-time monitoring of battery conditions and environmental parameters, it could provide early warnings for thermal runaway, a leading cause of EV fires. Beyond automotive applications, the technology holds promise for spacecraft, where integrated sensing and imaging are crucial.
The research was supported by several Chinese funding bodies, including the National Key Research and Development Program and the National Natural Science Foundation of China. As the technology advances, it could become a key component in next-generation autonomous vehicles, offering a more integrated and efficient approach to vehicle perception and safety.
