# LILYGO T-Energy S3

> Affordable ESP32-S3 development board with 16MB flash, 8MB PSRAM, integrated 18650 battery holder, WiFi, and BLE 5.0 for battery-powered IoT sensor nodes under $10.

## Quick Facts

- **Brand:** LILYGO
- **Board Type:** dev-board
- **Price:** ~$9.7
- **Product Readiness:** developer
- **CPU:** Xtensa LX7 dual-core @ 240MHz, FPU, AI instructions
- **CPU Architecture:** Xtensa LX7
- **CPU Cores:** 2
- **RAM:** 512KB SRAM
- **PSRAM:** 8MB
- **Flash:** 16MB
- **USB:** USB-C
- **Power:** 5V + Li-Ion 18650
- **Operating Voltage:** 3.3V
- **Antenna:** Built-in PCB antenna

## Connectivity

- **Wifi:** 802.11 b/g/n
- **Bluetooth:** BLE 5.0

## Open Source

- **Firmware:** Yes
- **Schematics:** Yes
- **PCB Layout:** No

## Certifications

CE, FCC

## Compatible Firmware

arduino, micropython, esp-idf, esphome

## Use Cases

- iot-prototyping
- home-automation
- plant-monitoring

## Components

- **ESP32-S3** (mcu): Xtensa LX7 dual-core at 240MHz with 16MB flash, 8MB PSRAM, WiFi 802.11 b/g/n, and BLE 5.0. — [Datasheet](https://openhardware.directory/r?to=https%3A%2F%2Fwww.espressif.com%2Fsites%2Fdefault%2Ffiles%2Fdocumentation%2Fesp32-s3_datasheet_en.pdf&ref=openhardware.directory&product=lilygo-t-energy-s3&source=md-export)

## Protocols

- **SPI**: CLK: GPIO12, MOSI: GPIO11, MISO: GPIO13
- **I2C**: SDA: GPIO8, SCL: GPIO9
- **UART**: TX: GPIO43, RX: GPIO44

## GPIO Map

| Pin | Name | Type | Functions |
|-----|------|------|-----------|
| GPIO8 | I2C SDA | I2C | digital-input, digital-output |
| GPIO9 | I2C SCL | I2C | digital-input, digital-output |
| GPIO43 | UART TX | UART | digital-output |
| GPIO44 | UART RX | UART | digital-input |

## Description

## Overview

The LILYGO T-Energy S3 is one of LILYGO's most affordable ESP32-S3 boards at under $10, combining the power of 16MB flash and 8MB PSRAM with an integrated 18650 battery holder for convenient portable operation. The ESP32-S3's WiFi and BLE 5.0 enable wireless connectivity while running from a single 18650 cell.

The form factor is clean and breadboard-compatible, with standard pin headers exposing all major interfaces: SPI, I2C, UART, ADC, and GPIO. The onboard battery charging circuit enables direct USB-C charging of the 18650 cell, making it a true standalone wireless sensor platform without additional power management boards.

Ideal as a drop-in replacement for ESP32 or ESP8266 projects needing more memory — the 8MB PSRAM unlocks complex web interfaces, JSON parsing, and OTA updates that smaller boards cannot handle. ESPHome makes it straightforward to integrate as a Home Assistant sensor node for temperature, humidity, air quality, or motion detection.

## Where to Buy

- [LILYGO Official](https://openhardware.directory/r?to=https%3A%2F%2Flilygo.cc%2Fproducts%2Ft-energy-s3&ref=openhardware.directory&product=lilygo-t-energy-s3&source=md-export) — $9.70

## Resources

- [product](https://openhardware.directory/r?to=https%3A%2F%2Flilygo.cc%2Fproducts%2Ft-energy-s3&ref=openhardware.directory&product=lilygo-t-energy-s3&source=md-export)
- [github](https://openhardware.directory/r?to=https%3A%2F%2Fgithub.com%2FXinyuan-LilyGO%2FT-Energy-S3&ref=openhardware.directory&product=lilygo-t-energy-s3&source=md-export)

## Tags

`esp32-s3`, `18650`, `battery`, `affordable`, `esphome`, `lilygo`

## Images

![LILYGO T-Energy S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-energy-s3/ad90ac529d1d.jpg)
![LILYGO T-Energy S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-energy-s3/bd83a765e0d4.jpg)
![LILYGO T-Energy S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-energy-s3/9dad048e3340.jpg)
![LILYGO T-Energy S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-energy-s3/b04d193d45e4.jpg)
![LILYGO T-Energy S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-energy-s3/c0c935728c34.jpg)
![LILYGO T-Energy S3](https://nbg1.your-objectstorage.com/openhardware-directory/entities/lilygo-t-energy-s3/aa15f39401df.png)

> **Battery Powered:** 18650

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