How to calculate consumption?

Question

Printed circuit boards

Comrades, please help!
It is necessary to calculate how much mAh the LED strip and the controller for it will spend.
(Ws2811 60led per meter
and
Nodemcu Lua Wi-Fi on Esp8266) It is

written to the tape that it is 14.4 watts per meter. I have 4 meters.

Controller:
Supply voltage 3.3 V
External power supply 3.6–20 V
Current consumption: data transfer mode - 200 mA, data reception mode - 60 mA

Transmission is likely to be both here and there.

How do I calculate what the battery capacity should be so that all this works for 3 hours?

14.4 watts is that per hour?
If yes, then we consider for the controller:
3.7V x 0.2A = 0.74W

Add:
14.4 × 4 + 0.74 = 58.34W / h
So?

Can we do the same thing with a battery knowing its voltage and capacity?

The tape requires voltage from 12V, I will connect 4 pieces of Li-ion batteries (3.7V, 6800mAh) in series for it. The voltage is then 14.8V.
(And the power to the controller will go through a step-down converter)

And if you can do the same with the battery, then:
14.8V × 6.8A = 100.64W / hour
So?

Then
we divide 100.64 by 58.34 and get ~1.72h?
So I need a capacity of 13600mAh to last for three hours?

Answer 1

From the very beginning, it must be taken into account that getting 12 volts from lithium is ... well, inconvenient. At the maximum, when each element is charged up to 4.2 volts, we get 16.8 volts from 4 elements, which seems to be a bit much (the LEDs will be overloaded). At a minimum, when each cell is discharged for a safe minimum of 3.0 volts, we get exactly 12 volts, but you have this state for a very short time, because with further discharge, the battery controller (so-called BMS) will turn off the load.
If we take three elements, then these figures change to 12.6 volts at the maximum and 9 volts at the minimum, i.e. at the maximum of the norms (but again not for long), and at the minimum the light will be weak.
You can overcome this with a low-drop 3-pin voltage regulator (for example, LM1084, it can be adjusted to 12 volts), but this is a complication of the device. In general, you choose what to do.
Now about current and capacitance. In your case, since the supply voltage of the tape and the controller is the same (12 volts), it is more convenient to read through the current.
We divide 14.4 watts by 12 volts, we get the current of each meter of tape 1.2 amperes. For 4 meters of tape, this will be a total current of 4.8 amperes, and together with 200 milliamps of the controller - exactly 5 amperes.
This means that for 3-hour operation, 15 ampere-hours are needed, preferably with a 20 ... 30% margin (i.e. 18 ... 20 Ah). The idea immediately comes to mind to replace lithium batteries with the smallest of the automotive lead-acid batteries - it fits into this design better, since it does not require any stabilizers and BMS.