I really appreciate how many comments is in this discussion trying to help me. Many thnaks
It seems to get connected to wifi takes 3-6 secs (not always the same time) and device is powered around 14 secs in total, then goes to sleep for 300 secs as I wrote.
I tried in the past implemens into this code static IP instead of DHCP so the connection time is faster, but I was not successful. Also that API recommandation … I am not sure if I am so skilled to do it myself. I am more enthustiastic than coder or electrotechnician, unfortunately.
Also I can try to use DS18B20, but then I am not sure about the code to upload to the ESP (maybe I can try to use the code from the link I posted in the first post here, but then it will not communicate with Blynk I guess, and I really wanted to have thisconnected to blynk as it is really handy and easy to use - also share with family members)
btw slightly different question, what do you think about battery life and what would be the best battery type pick to use one such a thermometer outside? Especially in the winter as cold weather will have impact on battery life. Here in the winter is usaualy aprox -5 degrees Celsius
btw2 - here on the forum see this topic and my comment where I used ESP8266-12E and measured 75mA and 2,5mA in the deepsleep - so way more than 40uA and the projests was working for one month on batteries (sure, sifferent batteries - 4xAA, but not sure if the battery type play so significant role here)