STMicroelectronics makes lithium batteries perform better and last longer with high-accuracy BMS controller

STMicroelectronics’ L9961 battery-management-system (BMS) device provides market-leading accuracy and flexibility to enhance the performance, lifetime, and safety of Li-ion and Li-polymer batteries.

Suitable for battery packs up to 25V, the L9961 provides monitoring, balancing, and protection of batteries for diverse applications requiring the high energy density of lithium batteries. Cordless power tools, backup energy-storage systems, uninterruptible power supplies, portable and semi-portable equipment, and medical devices can benefit from the L9961’s advanced features.

The many built-in features include a dual pre-driver for controlling battery-pack safety relays, which can be programmed for high-side and low-side connection. An embedded non-volatile memory for configuration data relieves the microcontroller from reprogramming the device at each startup. An I2C interface handles configuration and host communication to share battery state-of-charge (SOC) and state-of-health (SOH). Thanks to a high-resolution analog-to-digital converter (ADC) and current-sense amplifier, the L9961 senses cell voltages with an accuracy of ±15mV and battery current to within 0.25% (more info).