Update from Farm-Team: Prototyping Update #3: Building an independent solar battery circuit

Power system shopping

Bought:

• AMS117 LDOs(step down 3.3V converters)
• 5 V step up voltage booster
• TP-4056 Lithium Ion charge controller
• 6V 200mA solar module
• 5V 81 mA solar module
• 3.6V 800 mAh NiMh battery
• 3.7V 186500 LiIon battery
• Z-Diodes, resistors, capacitors and LEDs

Basic power consumption (estimates built on data sheets of modules):

Sensor node:

Arduino Pro Mini 3.3V  1~5mA

ESP8266 0.01~170mA

Hygrometer 8mA

NiMh battery tests:

Connected 5 V solar panel to battery with Z-Diode to battery and the battery than directly into the RAW input of the Arduino board. I used 3.6V (3x1.2V) NiMh battery.

In the picture is a nodeMCU connected to the hygrometer instead of the Arduino Pro Mini. More in the next article.

LiIon battery tests:

Connected LiIon charge controller (TP-4056). to solar panel then to battery and charge regulator (AMS117 or other step down regulator, hasn't arrived yet). The charge controller keeps a steady 4.2V (full LiIon.

In this picture, yes again, cheating with a nodeMCU. The above drawing is very similar nodeMCU development board.

Soon to follow: results from tests.

Links:

http://www.home-automation-community.com/arduino-low-power-how-to-run-atmega328p-for-a-year-on-coin-cell-battery/

http://bbs.espressif.com/viewtopic.php?t=133