LILYGO T-Energy S3

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.