48 V Battery Management System (BMS)

48 V batteries tend to be created using Li-ion multi-cell battery packs using 8-16 cells. From a safety perspective, but also to ensure the best efficiency and longest battery life these battery packs need to be carefully monitored and controlled. This requires accurate voltage, temperature and current as well as battery state of charge (SoC) and state of health (SoH) monitoring. In addition for most efficient battery use, good cell balancing and battery optimization is a must.

Block diagram
Design considerations
Product listing
Videos
Support

Block diagram

Highlighted components are Nexperia focus products.

Charge balancing MOSFETs

Zener diodes

TVS diodes

e-fuse / regulation

Autosense translators

Analog switch

ESD protection

Buck converter

Related sub-systems (1)

Step-down DC/DC converter

MCU core supply

Related sub-systems (1)

DC/DC conversion for MCU core supply

Select a component

To view more information about the Nexperia components used in this application, please select a component above or click on a component (highlighted in blue) in the block diagram.

Design considerations

Depending on the current being drawn some systems can use internal cell balancing topologies, but where there is a higher current then external MOSFETs are recommended.
Engineers also have a choice between passive and active cell balancing, although active cell balancing is often more complex give, its need for charge storage elements
Zener diodes utilized in the cell balancing stage protect the FETs and battery cell

Product listing

LFPAK88: The automotive Power MOSFET driving power density to the next level

Providing a true alternative to D²PAK, Nexperia’s LFPAK88 delivers industry leading power density in truly innovative 8mm x 8mm footprint.

Bipolar transistors

Diodes

ESD protection, TVS, filtering and signal conditioning

MOSFETs

SiC MOSFETs

GaN FETs

IGBTs

Analog & Logic ICs

Automotive qualified products (AEC-Q100/Q101)