in my last post, I wrote about how I made battery powered temperature and humidity sensors for my home automation system. In this post, I’ll describe how I improved them.
I made two main improvements to the sensors, firstly I removed the LEDs from the esp8266, in order to increase the battery life, then I put all the sensors in small plastic boxes, which protects the circuits while making them look way nicer.
Improve power consumption
Using the deep sleep ability of the esp8266 chip, i managed to reduce the power ocnsulption greatly, which a;lowed me to last about a week on batteries. However, the leds mounted on the esp8266 were still drawing power all the time.
The solution is really easy, I just unsoldered them using my solder iron and a pair of pliers.

Well, that was easy. Next step is to put the modules in boxes.
Putting the modules in boxes
The DHT11 module (that senses temperature and humidity) will have to stand outside of the box, so the measured values are as close as reality as possible. Check out the picture legends for a description of each step!





















Working on these gave me lots of ideas for different sensors, stay tuned!
Can you tell me how many time your temperature sensor works with two batteries??
Hi there,
The battery holds for a bit more than a week, it could hold longer but the power board uses some mA all the time, draining the battery uselessly…
Out of curiosity where did you get the small enclosures. Great projects btw really enjoying the posts.
Hi there,
I bough them at my local electrical shop, here in Sweden.
Link here: https://www.jula.se/catalog/el-och-belysning/elinstallation/installationsmateriel/kopplingsdosor/kulodosa-402378/
Cheers,
Benoit
Hi man, you can use an ht7333 low power voltage regulator to power the board,and also you can power temp sensor via gpio0 pin,so when esp8266 deep sleeps it wont`t drain any power. Just make sure to set gpio0 pin high wen it weaks. Better use dht22 – it is more accurate and works fine down to 3V. My setup is similar,but I m expecting about 6 months battery life with 15 minutes sleep time. Also there is another usefull option to send battery percent and RSSI to domoticz. ?
Hi there,
Thanks for the tip! I ordered a couple of the HT7333 for my next project, let’s see how it goes.
Do you have some kind of protection circuit for your batteries?
Cheers,
Benoit
Hi,
Can I get more info about your setup? I would like to build a wireless temp sensor for domoticz, which runs on batteries.
Nice write up. Will be helpful for me when I start my build with DHT22’s and DS1820B.
According to this forum post, these regulators are quite good. I’ve ordered a couple: http://www.hobbytronics.co.uk/u1v10f3-3v3-regulator
Forum: https://discourse.southlondonmakerspace.org/t/esp8266-with-dht22-running-on-2-aa-batteries/415
Cheers, Damien