Powering nRF24L01 , HC-SR04 , Piezo Buzzer and Arduino Nano 3.7v/280mAh/1.04wh Battery

Thread Starter


Joined Sep 30, 2008
Hi everyone there
How are you all,

I am trying to make an Entry Point Alarm System with Arduino Nano Sensing with HC-SR04 interfacing with nRF24L01 and Piezo Buzzer (Disk) and would like to power it by 3.7v 280mAh 1.04wh charging with TP4056 powered by 6V 1W Solar Cell ... [The Project is still on Paper]

My question is the Battery I have 3.7v 280mAh 1.04wh will be able to power all these

Supply current in TX mode @ 0dBm output power :- 11.3 mA
Supply current in RX mode @ 2000 kbps :- 12.3 mA
Supply current in Power Down mode :- 900 nA

Quiescent Current :- <2mA
Working Current :- 15mA

Arduino Nano
Power Consumption :- 19 mA

is the TP4056 is sufficient to Charge the 3.7v 280mAh 1.04wh Battery by the 6v/1w Solar Cell

what else do I need to know more about this Project before assembling it

or if I use ESP8266-12e then
its The ESP8266 usually draws a peak current of about 250mA after it wakes up
and then more or less constantly draws around 70mA before it goes back to sleep

what will be the Smallest Battery I can use to Power the Project
Please Help


Joined Jul 10, 2017
There is not enough information available to give you an answer so you will have to do a feasibility study.
You will need to do some experimentation with the solar cell and a single Li Ion cell connected to the charger. Replace the resistor on the charger that sets the charge current with a potentiometer. Vary the battery charge current and plot it against the solar cell voltage. Repeat this at different illumination levels.
Then find out how many average hours of sunlight you can expect in your location for the different months of the year. If the solar cell is in a fixed location, you will also need to measure it's output when tilted at different angles to the sun. Using that information you can calculate whether you have enough power available per day to run the devices depending on the maximum number of times the alarm is likely to be activated. Then you can determine the capacity of the battery needed to run the devices during the night and on dull days.
Sorry I could not give you a more precise answer, but that's life!
Good luck,


Joined Apr 11, 2010
Just do a back of the envelope power budget. Without the piezo, your drawing 46.3mA. Call is 50mA. When the piezo is used or the ESP8266 wakes up, you’re going to be drawing a LOT more current.

Your battery is rated for 280mAH. Let’s ignore the piezo and wake up current for now. At best, you’re going to get 5.6 hours of operation. Much less in the real world.

In my part of the world, 5.6 hours is longer than one night. So the battery will die before it can recharge. It might be drawn so low, the cell will be damaged.

So my envelope says that won’t work. KeithWalker’s approach is the most .

Addendum: The standard Nano requires 5V. I’ve never used a 3.3V model.

Thread Starter


Joined Sep 30, 2008
Thanks dear @ KeithWalker’s and djsfantasi for your valuable time...
as I said ite still on my Drawing Board on Paper...

First lets make the Theory part clear then I will assemble the project...

as I said Entry Point Alarm System to be installed on the Entry / Exit point (Main Door)
Thanks for correcting me I made an very Big Blunder (Nano 3.3)
yes its operating voltage is 5v

now If i get the new Battery which one it should be ... , suitable for the project ( I selected this because i have (2x 3.7v/280mAh/1.04wh )
1 I have to get the New Battery + Which one ???
2 Do I have to change the charger (I came to know that as TC4056 is not suitable for the same battery)
3 I have never used Soler Cell in any of my projects till now (Using this because I have one 6v/1w Soler Cell)
so please guide me to the next level

any other suggestion are also welcome for the Entry Point Alarm System


Joined Jul 10, 2017
You don't have enough information on the solar cell to be able to do all the calculations needed, so you will have to make some measurements.
You can determine the capacity of the battery with some simple calculations: Calculate the average battery discharge current over 24 hours. Add 100% safety margin for dull days. The current x 24 will give you the required Ampere Hour capacity of the cell.
You have no documentation on the solar cell so you will need to characterize it as I mentioned in post #2. That will determine the optimum charge current to be set on the charger, and that, with the average sunlight hours will let you know if it can deliver enough average current to keep a the battery charged. It will be the same as the discharge current you calculated in the first step. If not, then you will need a different solar panel.