ESPimatic battery issues

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I mentioned in post 2 that I have 2 battery powered nodemcu/ds1b20 combis and that “I have no idea yet how long the battery powered nodemcu’s will hold.”

Now I know: Less than a week. I assume the development boards use way more “power” then the tiny esp-01 modules.

I had already tried with USB power banks but the 2 different power banks I have switch off when the equipment doesn’t draw power (when in sleep mode).

TRhat suprises me : http://blog.squix.ch/2015/06/eps8266-long-term-data-logger-update-31.html

Well, the guy from that article uses IKEA batteries. I used Philips.

He uses 3xAA where I used 4xAA connected to the 5V input, as my battery pack is a 4battery-type enclosure.
Maybe I should connect to 3.3V (and then 3xAA of course ).
I assume the 5V input is running over a power regulator which might draw substantially extra power.

Next try starting this afternoon. I let you know.

Edit: I had a 5 minute sleep where he has a 10 minutes sleep. Maybe that’s also something to look at.

@Harry-van-der-Wolf

Power regulator, LEDs or too long WIFI connection time might be the issue. You should check and measure this. Did you remove some power LED? This is important. Would be interested what your values are.

From my experience a rough estimation what could be expected:

E = 1200 mAh ___________________avarage battery capacity of Alkaline AA
tq = 300s, Iq = 0.020mA _________estimated sleep time and current
t1 = 7s, I1 = 80mA _______________estimated operation time and current

Im = ( tq * Iq + t1 * I1 ) / (tq + t1) = 1,87 mA ___avarage current
t = E / (Im * 24h) = 27 days _________ battery life time

guys, this is show and tell and not battery issues.
suggest to split the battery things off.

edit - just did it…
pls. discuss your battery proposals here

@leader21 : Thanks for splitting up. This indeed requires a separate thread.

@Heizelmann : I know the tricks of removing the power regulator and disabling/removing the led. I have done that to one of my Nano’s but I do not know how to do that to my nodemcu’s yet.

This post describes extensively the use of both solar power coupled to a battery for ultra-low power use.
He also describes how to disable the LEDs but he doesn’t explain how he did that. Fortunately the first article he references to is explaining that. The LED takes 8mA - 100x more then the chip itself!
And they claim that a static IP address requires less energy.
I will dive into it.

In theory a static IP would take less power, because the DHCP client doesn’t have to connect to the DHCP server every now and then to negotiatie on the IP address lease.

Maybe this helps? putting the modem to sleep

https://github.com/esp8266/Arduino/issues/460#issuecomment-168983380

when you want to sleep:

WiFi.forceSleepBegin();

and to enable WiFi again:

WiFi.forceSleepWake();

@Harry-van-der-Wolf said:

Next try starting this afternoon. I let you know.

Now I used 3 reloadable AA batteries. No further actions taken to reduce power consumption apart from the 5 minute deep sleep after which a DS18B20 took a measurement and “the thing” went to sleep again.
It died last night, meaning only 1½-2 days.
Even with the options mentioned in those articles it will never last as long and be as low power as an ATTINY, mysensors, sensor/RF transmittor or the like equipment.

I have setup a Nodemcu with 3 AA battery’s and ds18b20 to sleep for 10 minutes.
Will let you know what it does.

I tried again with 3 AA batteries this afternoon. I removed the LED from the nodemcu.
Things still in place and requiring extra power:

• DHCP: This means that it at least once in a while needs to contact the DHCP server and I assume after every deep-sleep as it is “off the net” during deep-sleep.
• mDNS: This means that the avahi deamon broadcasts itself on the network also after every deep-sleep.

(Now on ikea batteries but that’s just coincidence )

I am also using ikea battery’s it is running for 48 hours and still going, I wonder how long it can hold.

Just thinking : would it be possible to run a ESP on 40 Mhz instead of 80 Mhz, and would that give longer battery live ?

@koffienl On an arduino in sleep mode not, because its powered down. Is the MCU of the ESP powered down in sleep? If not it would work, else it won’t matter.

http://www.esp8266.com/viewtopic.php?f=32&t=8339#p41703
Basic sketch won’t matter only when using spiff it might give some savings.

My basic sketch with an ds18b20 running every 10 minutes is on 73 hours atm and still running.

there are some examples on running battery power on esp8266.com
maybe they help
http://www.esp8266.com/viewtopic.php?f=11&t=6854
http://www.esp8266.com/viewtopic.php?f=11&t=5453&p=28651&hilit=18650#p28651
and this nice one here
https://tzapu.com/minimalist-battery-powered-esp8266-wifi-temperature-logger/

@leader21 Thanks for sharing.

I like the looting of this notebook batteries. Plus undervoltage protection.
http://www.bntdumas.com/2015/07/19/how-i-got-a-buch-of-liion-batteries/
http://www.bntdumas.com/2015/07/19/how-to-undervoltage-protection-for-li-ion-batteries/
http://www.bntdumas.com/2015/07/23/how-to-battery-powered-temperature-and-humidity-sensors/

Hmm … I have a couple of bad laptop batterys overhere

i got my hands on one of those usb energy meters and checked the consumption of my esp’s lying around here.
I figured out that all are running constantly with approx 80 to 90 mAh without sensors attached. When sending data they use about 120 to 130 mAh for this very short period and continue with 80/90 mAh.
With the LED Matrix attached the consumption goes up to 130 mAh constantly and sending takes 170 mAh.

i now have tested the deepsleep feature. with 20 wakeups per hour (3 minute sleep )
the esp needs approx 4 mA/h if i can believe the energy meter …