Finally, you can use a D1 mini without a USB cable. Now it is really wireless.
Through the use of this baterry h. i. e. l. d. and the lithium battery you can use a D1 mini anywhere.
Power supply: just connect the lithium battery to the shield and to the power of the whole system D1 mini.
Charging: when the lithium battery becomes exhausted, there is no need to disconnect, you can use the USB port to charge.
Lithium battery CR2032 is not included
1x WeMos Battery Shield for D1 mini - power supply and charging lithium batteries