Esp8266 wifimanager wifi connect time at boot after deepsleep

Projects Networking, Protocols, and Devices
1

I'm using an esp8266 with wifimanager for a battery powered project.
When the esp8266 boots up it connects to wifi sends data using an api and then goes to deepsleep for 5minutes.

When the wifi credentials are gathered by the wifimanager it still takes 3seconds to connect to wifi.
Since this draws a lot of current from my battery , i would like to reduce the wifi connection time.

Reducing this from 3sec to 1sec could prolong batterylife from 2mos to about 6mos.

Any one with experience in this?

2

It is normal and you can't speed it up. If you use WiFi network without password (open network), it will be faster, I know at ESP32 it is like 160 ms, so I think with ESP8266 u will get same or lightly higher time, but still under second.

Also if you use ESP32 u should have faster connection time on WPA/WPA2 networks because of higher CPU frequency and cryptographics accelerators onboard.

3

You may get some tips from here for extreme low power ESP8266 tricks: #58 ESP8266 Sensor runs 17 days on a coin cell/transmits data (deep-sleep) - YouTube

4

It is certainly possible on esp8266 as i've seen it on youtube but i did not find a good guide yet.

It is even possible in 100ms but this is too advanced for me.
example of very fast wifi and data transmit in 100ms