Linear Technology demonstrates breakthrough wireless battery management
Analog Devices, Inc. is demonstrating what it claims is the industry’s first wireless automotive battery management system (BMS) concept car at one of the world's biggest industrial fairs, Hannover Messe, this week. The BMW i3-based car was engineered with help from Analog Devices’ recent acquisition Linear Technology Corp., a leading provider of battery stack monitoring ICs for electric and hybrid/electric vehicles, and Linear’s design partner LION Smart.
The BMS combines Linear’s highly accurate battery stack monitors with SmartMesh wireless mesh networking products, replacing the traditional wired connections between battery packs and management system. This significant breakthrough addresses the persistent reliability issues associated with automotive wiring harnesses and connections in electric and hybrid/electric vehicles, and simplifies the BMS design and manufacture.
“Linear’s innovations in two critical industry leading technologies enable wireless battery management at automotive reliability levels,” said Joy Weiss, President of Linear Technology’s Dust Networks product group. “The wireless BMS concept car, realized through the expertise of LION Smart’s BMS design, showcases our product vision.”
Weiss added that all of the major automotive manufacturers are searching for ways to improve the performance and reliability of their battery management systems as they move into higher-volume production. Linear’s high-voltage battery stack monitors deliver industry leading accuracy and reliability, enabling battery management systems that maximize battery pack performance and longevity.
The LTC6811 battery stack monitor is a complete battery measuring device for hybrid/electric vehicles for up to 12 series-connected battery cell voltages with better than 0.04% accuracy. Combined with Linear’s SmartMesh wireless mesh networking system, it addresses the persistent reliability issues associated with automotive wiring harnesses and connectors.
Field-proven in industrial Internet of Things applications, SmartMesh embedded wireless networks deliver >99.999% reliable connectivity in harsh environments by employing path and frequency diversity. In addition to improving reliability by creating multiple points of redundant connectivity, the SmartMesh wireless network enables flexible placement of battery modules and improves battery state-of-charge and -health calculations. Additional data can be gathered from sensors installed in locations previously unsuitable for a wiring harness. The network also provides time-correlated measurements from each node, allowing for more precise data collection.
A reference design to enable customers to demonstrate wireless BMS capability, including the LTC6811 battery stack monitor and SmartMesh wireless sensor network, will be available in the first half of 2017.