Battery knowledge · Data, communication and electronics

BMS power modes

The states a BMS moves between to save energy. In active mode it measures, estimates and drives the contactors; asleep it draws microamperes to a few milliamperes from the auxiliary battery and wakes on CAN traffic, ignition, a charger plug or a timer to check cells and balance. Sleep current decides how long a parked vehicle can stand.

Also called
sleep mode, active mode, standby mode, wake-up

Example

Data, communication and electronics: an example situation

2500 in a log might mean 25.00 °C, 2.5 V or raw counts. Units and scale must accompany the value.

Read BMS power modes alongside Auxiliary battery in this context. The small 12 V or 48 V battery in an electric vehicle that powers the controllers, lights and locks and wakes the BMS, kept charged from the high-voltage pack through a DC/DC converter. A flat auxiliary battery immobilises the car however full the main pack is.

Use in Lemonergy

Separate quantities from encoding and transport.

This is a reference concept. No executable Lemonergy block has been verified for this term.

References & further reading

Further reading on this topic

These sources provide broader context; they are not presented as citations for every statement in this entry.

  1. 3rd generation of the CAN data link layer

    CAN in Automation, CAN Newsletter · 2020

    Topic background · Classical CAN, CAN FD and CAN XL data-link concepts; publication describes the 2020 state.

  2. Getting Started with the BQ76925

    Texas Instruments · 2019

    Topic background · A concrete BMS analog front-end example: cell voltage, current, temperature measurement and MCU integration.