ESP32-S2 is new SOC from Espressif which has only WiFi connectivity but has much more GPIOs available than ESP32 and ESP8266, also it has USB native connection which opens lot of new possibility.
We already sell Espressif’s Saola-1R board which has ESP32-S2-WROVER module, but it’s not designed for battery operation and low power as uses general purposes LDOs and has no battery connection.
This is something we wanted to improve – we designed board with same module but add LiPo charger and now our ESP32-S2-DevKit-LiPo can operate on LiPo battery even when there is no external power supply, but on top of this we kept the same PCB dimensions and ESP32-S2-DevKit-Lipo is drop-in replacement for ESP32-S2-Saola-1R. We use same module with 2MB RAM and 4MB Flash so once you develop with Saola you can move to ESP32-S2-DevKit-Lipo and make your projects battery operated.
The new ESP32-S2-DevKit-Lipo uses ultra low power power supply circuit which makes current consumption during sleep only 6uA (4uA of them are due to the battery measurement resistor divider) this is 10 times less than our other boards.
Prototypes are build now and we run production and will have these in stock by the beginnings of June.
olimex 
May 21, 2020 @ 16:57:21
I am very interested in the circuit you use as fully charged LiPo batteries goes beyond 3.6V (maximum rating of ESP32). A low quiescent current low-dropout regulator will typically still have a quiescent current above 20uA.
May 21, 2020 @ 17:01:06
there are ultra low power LDOs which has quiescent current of less 1uA or Microchip MCP1700 series are about 1.5uA
May 22, 2020 @ 09:50:07
You can also use LiFePO4 batteries which have a lower voltage so don’t need a regulator. Just make sure you adjust the charging voltage to suit!
May 21, 2020 @ 17:45:39
Thanks. It seems that all these ultra low power LDOs have a limited current typically below 200mA or 250mA for the MCP1700 series. Did you find one that goes high enough for the ESP32-S2 or did you add beefy capacitors to accommodate to current spikes during WiFi transmission?
Jun 26, 2020 @ 19:21:05
Any update on this?
The post states “in stock by the beginnings of June”.
Is there a new ETA for this board?
I’m very interested in a board that uses less than 7uA.
Jul 16, 2020 @ 22:28:34
Any update from OLIMEX Ltd? Has this product been cancelled?
Jul 17, 2020 @ 08:41:20
no, but there is still work to be done, Espressif still has partial software support for the USB part of this chip, also their specs changed and now in sleep this chip minimum current rise to 20 uA not 5uA as they initial claimed. Their boards with this chip still rely on USB-serial external chip as their bootloader is serial not USB, so lot of stuff need to be complete before good board is released.
For the moment if you want to develop you can by Saiola-1.
Jul 17, 2020 @ 20:19:46
Thank you!
That’s a really useful explanation.
I would not need the USB functionality but I like the idea of getting rid of the external USB-serial chip.
However, 20 uA instead of 5 uA in sleep would be a deal breaker.
Sep 16, 2020 @ 09:04:15
A suggestion. Adafruit has a port of Circuitpython to ESP32-S2. Sooner or later micropython will follow.
If you have Circuitpython (or Micropython) on a board, it is useful to have a sdcard to store files.
Why not put the back of the pcb to good use and put a sdcard socket there?
The socket does not need to be populated; just the pads to solder a socket if you need one.
And if the socket has a card detect pin, Micropython will mount the sdcard automatically when you insert it.