---
title: "BatteryManagement"
date: 2025-01-27
draft: false
description: "a description"
tags: ["battery", "bms"]
---
# Battery Management Module

The PlantCtrl system uses an external **Battery Management System (BMS)** board that connects to the MainBoard. This module monitors battery voltage, current, and health metrics and communicates with the ESP32-C6 via I2C.

{{< alert >}}
The open-bms is a custom battery management board designed for this project. It uses a CH32V203 microcontroller to handle battery monitoring and protection. The older bq34z100-based battery management board is deprecated and located in the `__Legay_Unused` folder.
{{< /alert >}}

## Hardware

The Battery Management Board features:
* CH32V203 RISC-V microcontroller for battery monitoring
* I2C interface for communication with the MainBoard
* Battery voltage and current sensing

{{< alert >}}
The open-bms board does not use the bq34z100 fuel gauge IC. That component was used in an older legacy design now located in the `__Legay_Unused` folder.
{{< /alert >}}

## Integration with MainBoard

The battery management board:
* Connects to the MainBoard via a two-pin I2C bus
* Provides power connection to the battery
* Reports battery metrics via MQTT (if configured)

## Usage

* If available, the system will use battery metrics for deep sleep management when charge is critical
* The nightlight can be automatically disabled if battery level drops below a predefined threshold
* All battery metrics are published via MQTT when configured
* The system includes safety mechanisms to prevent overcharging and deep discharges through the battery's built-in protection circuitry

## Safety Notes

{{< alert >}}
The system requires a battery with built-in protection circuitry. The MPPT system does not include charge termination or overcharge protection - the battery itself must provide these safety features.
{{< /alert >}}

The CH32V203-based BMS monitors battery health and provides status information but does not control the charge/discharge limits. Ensure your battery can handle the maximum charging current from the MPPT system (up to 2.4A).

## Setup

1. **Connect Battery:** Connect your protected battery to the BMS board
2. **_connect MainBoard:** Connect the Battery Management Board to the MainBoard via the I2C bus connector
3. **Power On:** Power on the system and verify communication via MQTT

## Status Indicators

The BMS board includes status LEDs, they behave like every normal powerbank (1-5 lights, animted if charging)