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LED Strips connection Math for Power source


Dec 6, 2022
Dec 6, 2022
Hi. I do not have experience with lights and other electronics, so I apologize if this sounds like blabbering.

I am making a Portal companion cube, and I am going to have it light up. I've already cut LED strips to fit what I would need it to.
Since the box opens, the lid would be a separate power source. I know how to solder, and have a rough idea how I am wiring it together (but am open to suggestions) but I am stumped calculating the power source needed to power the strips.

I have included my math below for what I was able to solve.

Box - 230 LED Lights on strips
Lid - 46 LED Lights on strips

Strips (Before Cutting) Amazon Link
2m/ 6.56 ft to 3AA (4.5V) (About 117 LEDS per strip)
SMD 5050 Diodes
3 Watts
Color: Warm White
Each strip between where you cut also says DC5V
Length of Box Total - 391 cm (12.8281 ft)
Length of Lid Total - 78.2 cm (2.565617 ft)

If I am doing my math right,

3 watts/ 6.56 ft = 45731707 watts per foot (WPF)

12.8281 ft x .45731707 WPF x 1.2 = 7.03981098 Watts
2.565617 ft x .45731707 WPF x 1.2 = 1.40796053902 Watts

So I should be able to power the box with this Battery Box (8AA(12v) ) and the lid with this Battery Box (3AA(4.5V)) or this Battery Box (2 CR2032(3v)).

Box Wiring has 5 Panels, lid has 1.

If this is correct, about how long would the batteries last? Anything I should worry about?
If it is incorrect, please help me understand where I went wrong.
Thank you.


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Jun 25, 2010
Jun 25, 2010
Total length (14ft) is very little more than the whole strip at 2m. What does the package say about battery life? Whatever it says the batteries will last around 5% LESS - probably not noticeable by the user. Will depend on the TYPE of battery used.

CR2032 about 2 minutes /s...... AA's a lot longer.

It's a suck-and-see situation.