In a significant advancement for battery management technology, Renesas Electronics has unveiled an all-encompassing battery management system tailored for its fuel gauge chips used in consumer applications ranging from e-bikes to drones. Announced on March 19, 2025, this new system introduces the R-BMS F (Ready Battery Management System with Fixed Firmware), designed to facilitate the rapid development of safe and power-efficient power systems.
The R-BMS F firmware, which operates on the RL78 microcontroller mounted on a battery fuel gauge IC (FGIC), offers extensive support for lithium-ion batteries configured in both 2-4 and 3-10 cell series. This innovative setup is crucial in battery management systems, enabling precise monitoring of the state of charge (SoC), state of health (SoH), current, and temperature, while actively balancing the voltages of individual cells to prevent malfunctions and enhance performance.
In many instances, consumer electronics developers may lack the specialized expertise necessary to design control algorithms that uphold safe battery operation and ensure prolonged battery life through numerous charge/discharge cycles. Recognizing this barrier to effective design, Renesas has loaded the R-BMS F with pre-tested firmware tailored to work seamlessly with the FGIC's on-board MCU. The firmware comes packed with essential pre-programmed functions to maximize battery longevity and safety, including cell balancing, current control, as well as voltage and temperature monitoring.
“One of the biggest bottlenecks for designing advanced power management solutions is the complex task of firmware development and validation,” stated 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 specialized technical knowledge of MCU programming or advanced battery management design.”
To further ease developers' challenges, the battery management system allows customization of numerous parameters to align with specific needs, as well as adjustments for different cell chemistries leveraging a user-friendly graphical interface (GUI)—all without necessitating a complete integrated development environment (IDE).
Renesas offers two variations of the R-BMS F system, each accompanied by a full evaluation kit featuring all necessary hardware, software, tools, and documentation for immediate development initiation. The analog section of the kit provides precise measurements of cell voltage, current, and temperature, along with control for external MOSFETs and the conversion of analog signals into digital. The digital section comprises synchronous functions like the main CPU, clocks, timers, and serial interfaces.
Included within these evaluation kits are pre-programmed firmware stored in embedded flash memory, which enables flexibility in configuring battery pack and cell chemistry parameters, a USB System Management Bus (SMBus) interface, GUI-based software, communication cables for host system connectivity, dedicated tools for parameter setting, and comprehensive documentation that includes schematics and an engineering bill of materials (eBOM).
The RTK0EF0163DK0002BU R-BMS F targets solutions for 2 to 4 series cells (approximately 8V to 16V), making it ideal for smaller devices like vacuum cleaners, robotic vacuums, and various medical and consumer devices. This variant operates with the RAJ240055 Li-ion battery FGIC. Additionally, Renesas has created a Smart Robot Vacuum Cleaner design by integrating this FGIC with other devices from its extensive portfolio.
Conversely, the RTK0EF0136DK0002BU R-BMS F functions for 3 to 10 series cells (roughly 12V to 40V), utilizing the Renesas RAJ240100 and RAJ240090 Li-ion battery FGICs. This model is poised to cater to applications within e-mobility, drones, and other industrial as well as consumer systems. Impressively, both R-BMS F solutions are already available in production volumes.
On the legislative front, the New South Wales government of Australia has made considerable strides in addressing safety concerns regarding lithium batteries, notably in electric scooters and bikes. Also coinciding with Renesas' product launch on March 19, 2025, the government introduced the Product Lifecycle Responsibility Act to parliament. This marks a pioneering step, positioning NSW as the inaugural state to enact laws regulating the handling and disposal of lithium batteries.
The impending legislation is set to implement mandatory stewardship schemes for suppliers of batteries and related products. This initiative mandates compliance with rigorous safety protocols concerning the design and manufacturing processes, including the recycling, reuse, and secure disposal of batteries. Recognizing the alarming statistics surrounding battery incidents, which reportedly account for between 10,000 to 12,000 fires annually in trucks and waste facilities due to improper handling, the legislation aims to mitigate future dangers.
Fire and Rescue NSW has recorded 384 incidents involving lithium-ion batteries since 2024, which tragically resulted in 33 injuries and multiple fatalities. Environment Minister Penny Sharpe emphasized the urgency of these regulations: “Batteries power our modern life and we will need them more as we decarbonise our economy,” reflecting the undeniable need for safe management as battery use proliferates.
The new laws will require battery suppliers to register their products while facilitating safe recycling and disposal through designated collection points. They will also need to launch public awareness campaigns concerning battery risks and disposal practices, alongside enhancing battery design, packaging, import, and storage to elevate both safety and recyclability. Importantly, these regulations will also encompass smaller embedded batteries found in everyday devices such as portable vacuums, electric toothbrushes, and children's toys.
In summary, Renesas’ significant advancements in battery management technology align well with New South Wales’ proactive legislative measures aimed at fostering consumer safety within the growing battery market landscape. These developments underscore the dual commitment to innovation and environmental responsibility required in today's rapidly evolving technological realm.
