Maximizing the Usage of Li-ion 18650 Batteries: Applications, Sales Ideas, and Pricing Guide

I have several Li-ion 18650 batteries at home. I have no idea what I can do with them. Some are bought online and others are from laptops, all functional, voltage above 2.5V, and most above 3.5V. Where could I use such batteries, or is it worth selling them, if so where and for how much. On one page I saw 2,600mAh for PLN 13, would it be worth selling my (with similar capacities) for PLN 10?
Any advice, ideas and suggestion would be appreciated.

Kalvi wrote:

On one page I saw 2,600mAh for PLN 13, would it be worth selling my (with similar capacities) for PLN 10?

And you would buy a battery from an uncertain source for PLN 10, being able to add PLN 3 and buy a new one?
On Volume you can buy batteries from disassembly of tablets with capacities of 5000mAh at a price of 5-10 PLN. They have all the boxes, not many eager.

Your batteries, regardless of their condition, have a scrap value because they are not new and it is not known whether they are functional. Just because they have some voltage does not mean that they are functional and hold capacity.
If you don't know what to do with it, give it away because you won't break the property anyway. Unfortunately, that's the truth.

Artur k. wrote:

Kalvi wrote:

On one page I saw 2,600mAh for PLN 13, would it be worth selling my (with similar capacities) for PLN 10?

And you would buy a battery from an uncertain source for PLN 10, being able to add PLN 3 and buy a new one?
On Volume you can buy batteries from disassembly of tablets with capacities of 5000mAh at a price of 5-10 PLN. They have all the boxes, not many eager.

Your batteries, regardless of their condition, have a scrap value because they are not new and it is not known whether they are functional. Just because they have some voltage does not mean that they are functional and hold capacity.
If you don't know what to do with it, give it away because you won't break the property anyway. Unfortunately, that's the truth.

I do not intend to make a fortune, but since they are no longer useful to me, I would like to earn at least a few pennies or use them in something else. The only question is what. What could you do with them, beyond power banks?

Buy yourself a flashlight.

Kalvi wrote:

And I have no idea what I can do with them.

You can make a soldering iron powered by these cells.
https://www.elektroda.pl/rtvforum/topic3303762.html

Kalvi wrote:

What could you do with them, beyond power banks?

Can be used to power almost any mobile device. You just need a little imagination.

Make a lighting supply (and cell charger) for the bicycle.

On the basis of some old radio you can do 3in1
Portable radio with a flashlight and powerbank.

Old screwdrivers, shavers, flashlights - I have all changed at home.
In the bike I also have all the lighting on 18650.