The NiMH cells continue to preform, despite unpleasant cold.

Electronics
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The NiMH cells continue to preform, despite unpleasant cold. 3 AA cells versus an ESP-12F, active for 60 seconds every 5 minutes.

This test has been running since Feb 3, and the last voltage reading was 3.6v at -8.5°c.

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Hello, can you share schematic and code which you use in this experiment? Thanks!

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Hello @Alexander_Ribchansky I will put the schematic and code here: https://github.com/gordonthree/batTemp

I’m at work right now, and the code is at home, check back later and I’ll post it up.

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Thanks! Will checkout schematic as soon as reach my notebook with eagle;) will wait for code either!

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I have uploaded the Arduino sketch I’m using.

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This is really interesting work, thanks for sharing it with us. Can I ask how you measure the voltage on the battery and input this measurement to the esp?

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Hi @Stefan_Nordlander . I am using the built in ADC routine, ESP.getVcc() to read the voltage on the Vcc pin, which is also the battery voltage. You can divide the number by 1023 to get a more exact voltage, or just count the reading as millivolts.

On another experiment, I put a 10K0 + 2K2 voltage divider across the battery terminals, and attached that to the TOUT pin (ADC / AN0). 10k0 + 2k2 gives handles a maximum voltage of 5.545 volts scaling to the 0-1v range.

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@Gordon_McLellan Thanks alot, did not know abot that function. It was very helpful indeed.