Customer:
I am developing a temperature monitoring system for freezers and refrigerators using WiFi and MQTT. I have chosen the ESP8266 because I do not need Bluetooth or higher clock speeds for simple temperature measurements and data delivery. The board has an onboard JST connector for battery power, but I need to know whether there is any form of surge protection (“battery shield”) integrated into the board itself.
Originally submitted via email support on 3 December 2025. Migrated to the forum for community visibility.
Soldered Support:
The CONNECTPLUS has a JST battery connector and a charger IC which acts as a shield between the battery and ESP8266 microcontroller, designed to work with Li-Ion 3.7V batteries. When you plug in Dasduino CONNECT via USB the battery will charge automatically, and when you unplug USB, the battery will begin to be drained, giving you maximum battery life.
If you are aiming to use an ESP32 microcontroller with Li-Ion batteries and deep sleep, consider the NULA DeepSleep ESP32-S3 board instead. It has only a few microamps in deep sleep, allowing for longer battery life for a project like this, and features the same I2C connectivity (JST battery connector, Qwiic connectors, etc.).