How to implement lighting?

Question

Electronics

I want to make a night lamp, there are no problems with the body - I made it.

Hull photo

Illuminated questions. I don’t plan to put 220 inside and put a regular led lamp, it’s not very safe.
There is a li-on battery and a tp4056 board and a desire to organize LED backlighting. Please tell me how to choose LEDs and how to make an output voltage of 3.7-3.9 volts and LEDs that apparently are designed for 3, 3.2 3.6 volts.

Answer 1

An LED has two key parameters - direct operating current and voltage drop across it.
If the LED is designed for 3.6 V and its operating current is, for example, 100 mA, then to power it from 5 V, for example, you need to put a current-limiting resistor, which is calculated as follows:
(5 V - 3.6 V) / 100 mA = 14
Ohm voltage has a spread depending on its charge. A charged battery can produce, for example, 4.2 V, and a discharged one 3.7 V.
It is better to calculate at the maximum if you want the circuit to last longer.

Answer 2

I don’t plan to put 220 inside and put a regular led lamp, it’s not very safe.

Why?

how to make friends with an output voltage of 3.7-3.9 volts and LEDs that, apparently, are designed for 3, 3.2 3.6 volts.

They, in theory, should not be scared, but hang a resistor.
I would not bother and put an LED light bulb there.

Answer 3

You come to the supermarket with electronics, you say "sell me a meter of LED strip and a power supply"

That's it.

Answer 4

LEDs are usually connected to an LED driver.
The driver actually monitors that the brightness does not fall when the battery sits down smoothly and does not allow the diode to burn out.
So if you decide all the same on the battery, then decide on the number of diodes, their power and select the appropriate driver for them.