BM2 battery monitor for Home Assistant (Marketplace integration)

Installs: 56 sharing analytics
GitHub stars: 9
Connection: Works locally
Upkeep: Updated in the last 6 months
Version: v1.4.1, September 4, 2026
Category: Hubs and protocols, Wireless protocols
Kind: Marketplace integration
Needs: Needs the Marketplace (HACS on 2026.10 and older)
Domain: ha_bm2monitor
Source: github.com/andystewart999/ha_bm2monitor
Issues: Report an issue

Independent directory, made by the developer of Vulpo. Not affiliated with Home Assistant or the Open Home Foundation.

About

BM2 battery monitor is an integration that reads battery information from BM2 devices over Bluetooth. It works locally, and Home Assistant discovers the devices on its own and offers to add them. The integration creates sensors for battery voltage, percentage and general state. It uses an explicit connection to the device instead of BLE broadcasts, which carry only the percentage. Battery chemistry can be chosen, and this changes how percentage and status are calculated from voltage. Options cover a limit on how often sensors update and custom voltage values for a battery, such as the thresholds for low, critical, floating and charging.

Automatic summary of the README and code of andystewart999/ha_bm2monitor. Something wrong, or are you the maintainer and want your own text here? Get in touch

Supports

Works locally Talks to your devices on your own network. No vendor cloud in between.
Found by itself Home Assistant spots it on the network and offers to add it.
From the Marketplace Installed through the Marketplace, formerly HACS.
Actively maintained Its author released or pushed a change in the last six months.

Provides

Sensors

Setting it up

Install it from the Marketplace and restart Home Assistant, then add it under Settings, Devices and services.

BM2 Battery Monitor

Bluetooth device
Battery chemistry

BM2 Battery Monitor discovered

Battery chemistry

After setup

Sensor update rate limit:
Sensor update rate limit (seconds)
Battery chemistry
Battery name, type or chemistry
Critical voltage threshold (0% remaining)
Low voltage threshold (20% remaining)
50% remaining voltage
100% remaining voltage (while not being charged)
Floating voltage
Charging voltage

Texts from the code of andystewart999/ha_bm2monitor.

From the README

A custom integration to monitor the BM2 battery monitor via Bluetooth.
It discovers BM2 battery monitor devices and creates sensors based on battery voltage, percentage and general state via explicit connection rather than BLE broadcast, which is what most other BM2-supporting integrations do. BLE broadcasts only contain the percentage unfortunately.

From the README of andystewart999/ha_bm2monitor, MIT License. Shortened.