Efficient management through monitoring of Li-ion batteries is critical to the progress of electro-mobility and energy storage globally, since the technology can be hazardous if pushed beyond its safety boundaries. Battery management systems (BMSs) are being actively improved to reduce size, weight, and cost while increasing their capabilities. Using power line communication, wireless monitoring, or hybrid data links are one of the most advanced research directions today. In this work, we propose the use of radio frequency (RF) transceivers as a communication unit that can deliver both wired and wireless services, through their superior analog and digital signal processing capability compared to PLC technology. To validate our approach computational simulation and empirical evaluation was conducted to examine the possibility of using RF transceivers on a direct current (DC) bus for wired BMS. A key advantage of this study is that it proposes a flexible and tested system for communication across a variety of network scenarios, where wireless data links over disrupted connections may be enabled by using this technology in short-range wired modes. This investigation demonstrates that the IEEE 802.15.4-compliant transceivers with operating frequencies of 868 MHz and 2.4 GHz can establish stable data links on a DC bus via capacitive coupling at high data rates.

Lithium-ion batteries are increasingly common in high-power, safety–critical applications such as aerospace, spaceflight, automotive and grid storage. The voltage and power specifications of such applications usually require large numbers of individual cells combined in series and parallel to form a battery pack. It is then the role of the Battery Management System (BMS) to monitor these cells condition and ensure they remain within safe operating limits. To minimise cost and complexity, it is typical to monitor only a fraction of the cells in a battery pack. This creates potential safety and reliability issues and requires conservative limits imposed on the overall system to ensure safe operation. This is insufficient in high-power, safety–critical applications and thus alternative approaches to battery management are required. Here we demonstrate the development of novel miniature electronic devices for incorporation in-situ at a cell-level during manufacture. This approach enables local cell-to-cell and cell-to-BMS data communication of sensor data without the need for additional wiring infostructure within a battery module assembly. The electronics firmware and hardware integration within the cell’s electrode stack is demonstrated to function after triggering post cell formation and through cycling and electrochemical impedance analysis. This work shows that the proposed approach has a negligible impact on the cells’ performance and highlights a new technique for active monitoring of the cell’s in-situ conditions. This research will enable new methods of cells characterization and monitoring for optimum electrochemical and thermal performance while improving system safety.

As the RF communication on 18650 Li-ion cell level has not been reported due to its challenges and constrains, in this work, a valid wireless data link is demonstrated in an enclosed empty metal shell at 868 MHz and 2.4 GHz based on the IEEE 802.15.4 standard. The experimental tests are carried out using two generic unturned radiative structures, a wire loop fitted inside a cell shell, and an open terminal sub miniature version A (SMA), subsequently oriented vertically and horizontally relative to the ground plane. Based on signal strength indicator, bit error rate, and packet error rate, the test characterized a payload of 120 bytes at the highest speed of 150 kbps and 250 kbps supported by the IEEE 802.15.4 for the two communication frequencies. A MATLAB simulation is used in parallel to determine the three-dimensional radiative pattern of the two structures, whereas a three-ray model for multipath range propagation is implemented to complete the empirical experiments. It was demonstrated through testing communication of up to 10 m for both operating frequencies, proving the concept of wireless cell communication within short ranges, an essential feature for monitoring the health of each cell inside future electric vehicles (EVs).