Complete li-ion battery management platform with pre-validated firmware

Renesas Electronics Corporation has introduced all-in-one solutions for managing li-ion battery packs in a wide range of battery-powered consumer products, such as e-bikes, vacuum cleaners, robotics and drones. With pre-validated firmware provided, the R-BMS F (Ready Battery Management System with Fixed Firmware) will greatly decrease the learning curve for developers, allowing rapid designs of safe, power-efficient battery management systems.

Designed for li-ion batteries in 2-4 and 3-10 cell series (S), R-BMS F solutions include the company’s industry-leading fuel gauge ICs (FGICs), an integrated MCU and an analog battery front end, pre-programmed firmware, software, development tools and full documentation – all available in complete evaluation kits that are now ready to ship.

Firmware is vital in battery management systems as it monitors batteries’ state of charge (SoC), state of health (SoH), current, and temperature, actively balances the voltages of the individual cells, and detects faults. In some cases, however, consumer electronics developers may lack the highly specialised expertise to develop control algorithms that keep the batteries functioning in a safe temperature region and provide adequate battery life over many charge/discharge cycles.

The company’s R-BMS F solutions include built-in, pre-tested firmware designed to work with the FGIC’s on-board MCU. The firmware consists of critical pre-programmed functions to maximise battery life and ensure safe operation. These include cell balancing, current control, and voltage and temperature monitoring. For added flexibility, the battery management system lets developers set many parameters to meet specific requirements and adjust the solution for different cell chemistries via a GUI without needing a full IDE.

“One of the biggest bottlenecks for designing advanced power management solutions is the complex task of firmware development and validation,” said Chris Allexandre, senior vice president and general manager of Power at Renesas. “Not everyone has the expertise or in-house resources to write their own algorithms. Our all-in-one R-BMS F battery management system eliminates this process and provides market-ready power solutions that work without requiring specialised technical knowledge of MCU programming or advanced battery management design.”

Both R-BMS F solutions contain a full evaluation kit with all the hardware, software, tools and documentation needed to start developing. The underlying hardware powering the R-BMS F is the company’s FGIC solution, which combines an analog battery front end and an ultra-low-power RL78 MCU into a single, small package. The analog portion provides accurate measurements of cell voltage, current and temperature, controls the external MOSFETs, and converts analog data to digital signals. In the digital section, synchronous functions reside, including the main CPU, clocks, timers and serial interfaces. Also included in the evaluation kits are: pre-programmed firmware stored in embedded flash memory with the flexibility to set the battery pack and cell chemistry parameters; the USB System Management Bus (SMBus) interface; GUI-based software; cables to communicate with the host system; dedicated development tools for parameter setting; and full documentation, including schematics and an eBOM. With these resources, developers can confidently innovate intelligent power management systems that safely monitor battery usage and provide longevity, while reducing their impact on the environment. Renesas plans to include turn-key R-BMS F solutions in all future FGICs.

The R-BMS F for 2 to 4S cell (~8V to 16V) solutions targets small vacuum cleaners, robotic vacuums, consumer and medical devices and runs on the RAJ240055 Li-ion battery FGIC. The company offers a Smart Robot Vacuum Cleaner by combining this FGIC with other devices from its portfolio.

The R-BMS F for 3 to 10S cell (~12V to 40V) solutions runs on the RAJ240100 and RAJ240090 Li-ion battery FGICs. Its target applications include e-bikes, e-mobility, vacuum cleaners, robotics, drones, and industrial, consumer, and medical systems.

The company has combined these FGICs with other devices from its portfolio to create a wall-to-battery Low-Power Energy Storage System and a USB-PD All-in-One Battery and Charging Solution.