That's strange - I use a similar kind of battery quite a lot, and it seems fine. Those should supply well over an amp, and realistically Espruino WiFi isn't going to draw any more than 0.5A - even for fractions of a second.
How do you have it connected, and do you have USB connected as well? That can be difficult on Espruino WiFi
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
That's strange - I use a similar kind of battery quite a lot, and it seems fine. Those should supply well over an amp, and realistically Espruino WiFi isn't going to draw any more than 0.5A - even for fractions of a second.
How do you have it connected, and do you have USB connected as well? That can be difficult on Espruino WiFi