NXP Semiconductor has developed the first battery management system (BMS) using ultra-wideband (UWB) technology, writes Nick Flaherty.

Using wireless connections between battery cells and the BMS in a pack simplifies assembly and enables better energy density. It also removes the weight of the wiring harness and eliminates connectors. However, many wireless BMS implementations based on narrowband radio-frequency connections at 2.4 GHz, such as Bluetooth, suffer from interference.

The UWB technology developed by NXP provides higher resistance to reflections and frequency-selective fading in the pack to enable more robust and reliable transfer of cell data, such as voltage and temperature measurements. High-bandwidth pulses carry the data.

UWB is already used for secure access to vehicles, such as keyless entry, as it is short-range and more difficult to intercept than other wireless technologies. The signals do not penetrate outside the pack, avoiding interference with other wireless systems.

The chips operate from 3.1-10.6 GHz with 500 MHz bands. The transceivers can be simpler than the chips used for keyless entry as the ranging and sensing functions are not needed.

“Our wireless BMS system is the industry’s first to include UWB technology, offering manufacturers the most advanced technology to power tomorrow’s EVs,” said Naomi Smit, GM & VP battery management systems at NXP.

“Trimension UWB delivers simple, safe and robust wireless communications within the BMS, outperforming existing narrowband-based solutions. We are proud to work with our customers to make the wireless promise a reality.”

The Trimension UWB is part of NXP’s FlexCom chipset, which supports both wired and wireless BMS configurations with common software architecture and safety libraries. It will be available for evaluation and development in the second half of 2025.

The FlexCom BMS chipset includes a chip for a battery junction box that provides accurate voltage and current measurements with chassis isolation.