As I asked earlier you need to know all these things before you can do the calculations to determine what combination of battery and panel will work.
You need to experiment. There are power banks that charge and power simultaneously. Others donāt. There are power banks that shut down when current draw is low (like Esp deep sleep), others donāt.
That sounds good. Observe that and If you really can provide 24h power for esp with 2h solar charge, you have many options here.
Itās all about math at the end.
Experimenting is fun. Messing around with lithium batteries can be risky.
-Solar panel is 10w 5v
- 2 dayuse (my 5000mah powerbank was able to run it for 24h)
the least amount of sun I have is from 8am to 18pm in Summertime is till the 20pm
Regarding the powerā¦
I have different ideas and projects, but as I said above, with a 5000mAh power bank I get about 24-30 hours of battery lifeā¦ for that, Iāll be trial and error, like with most of my projects. I need to figure out what kind of devices I can easily install so they work. If it only lasts 5 hours, no problemā¦ Iāll either upgrade the batteries or replace the panel.
That is not what I asked.
And you did not answer the others.
Iām done. Good luck.
Or 2W?
And when thereās rainy winter season, days without visible sunā¦?
Measured or from AE/Amzn description?
I never mentioned 2w
it usually doesnāt rain more than two or three days in a row.
But the issue isnāt the battery sizeā¦ Iāll replace that myself. I need to know the right components to install, just a few and not too complex. But as I said, a 10,000 mAh battery pack should be fine. If not, Iāll fix it with DeepSleep or inactivity schedules.
I donāt care about battery life. Iāll adjust that based on what happens with DeepSleep, periods of inactivity or a larger battery.
But a 10,000mAh battery should be more than sufficient.
What I care about are the components to ensure everything is safe.
It looks like the solar panel you bought thinking it was 10 W is only about able to produce a maximum power of 2W. Earlier in the conversaton it was mentioned that it is common practice for sellers to vastly exagerrate the power of hobby solar panels. Even the 2W is theoretical i.e. You will never get even 2W. Perhaps for short periods you might get close. The sun will move. There will be clouds.
Adding more cells in parallel to have a larger battery brings itās own problems. Charging lithium cells in parallel is tricky. Those battery shield with room for 3 or 4 lithium cells will not be useable. A single cell V3 battery shield is able to work with deep sleep without powering off when very low current.
If you donāt want complex why not just buy a solar powered weather station to save you time and money from buying a lot of stuff that wonāt work.
There are many share your project threads showing how to build solar projects if you must have a go.
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I did.
Thatās more less what you get out of that panel.
Imax is 600mA on description, so Wp is 3W. In real life ~2W.
Now the main question is, what electronics there are built-in. Since itās sold for usb charging, there is quite surely some regulator in. If that regulator has āpseudo MPPTā feature that regulates the output current preventing the voltage to collapse, then It should work out of the box to power some 5V device or to charge power bank.
But it doesnāt have any battery charging circuit. So if you want to use that panel you need to use it to charge power bank or buy a board that has battery management and Usb charging. Like Xiao Esp32 or Dfrobot firebeetleā¦
The board the OP showed has several LDO and a boost circuit. They are always on so there is a significant quiescent current. The charging circuit seems to be very much like a TP4056.
Thatās basically a power bank.
What I wrote above was related to the circuit that solar panel has. The point here is if it has any voltage-tracking built inā¦
I have the white version of that solar panel. Again I bought it as a 10W. Itās just a solar panel with wires connected to + and - with a small plastic cover on the back.
I plugged that panel into that battery shield this summer to see if it would charge a phone. It wasnāt very good. Phone is bit of high load so inductor heated up quite a bit even with a heat sink on it.
Can you open the āboxā on the panel where the USB-cable is connected?
I would be very surprised it there is not some controller inside. It would be unsafe to connect Usb devices directly to solar panel. 5V panel can have 6.5Voc in low temperature
No, I canāt get to it. Iāve use those battery shields well V3 anyway with panels that do read on my meter at 6.5V for extended periods with no problem. I think TP4056 has max input voltage of 8V.
This is the back of the battery shield though.
Yep. My 6V panels have 7Voc and didnāt fry TP. But you need to set the charge current to max 2/3 of the panel Imp to get reasonable results.
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Thereās that same panel OP has with built-in 6Ah battery available.
Notice more honest W rating hereā¦
I have only realized that recently when I started to use very small panels.
My first idea was a powerbankā¦ like this:
But the prices are very high for what theyāre used for, and Iād rather get a power cord. Donāt get me wrongā¦ Iām not worried about the ā¬40 plug, but I think itās ethically wrong. Especially since I know a similar product wouldnāt cost more than ā¬5 if assembled by myself.
I would worry. Many power banks shut down if current draw drops below certain threshold (they are correctly designed for that), so when you set esp to deep sleep it might become deeper than you intendedā¦
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