Do not discard the old cartridge.

When some parts fail, we usually throw them away, replacing them with new ones. But there are times when broken or aged parts should not be disposed of, as they can become useful in creating something new and unusual. The cartridge is about the same story. With it, you can design a fully operational power bank.

First of all, you need to know that you can find such a cartridge in an old laser printer. Inside the part is a small photo drum. Often it is painted, quite durable and light. It is in it that special batteries of the 18650 format should be placed.

Equipment

First, clean the toner cartridge. The smallest amount of the second element will immediately stain all your clothes and hands.

Next, unscrew the sides of the cartridge and remove the photo drum from there.

The drum should now be disposed of with toner.

The next step is to remove the plastic rails. The action is easy to do with a hot air gun.

We are preparing two batteries, such as in the photo. In the future, they will be used in the design.

An ordinary Chinese module can serve as a boost converter. Such parts are quite compact and easy to use.

Charging must be performed using the charge controller in which the protection is installed. This will help to keep your phone safe and sound, so protection is required.

The boost converter should be turned on with a microtumber switch. This size fits perfectly into the overall picture.

Manufacture

Batteries need to be soldered together so that the "cons" were connected to each other. The wire must be soldered at the junction. A similar story with a plus. It is advisable to cut off the nickel-plated tape in order to subsequently solder the wires in its place.

Case caps are cut out of plastic (see a photo).

It is necessary to mark all the holes, cut them with a knife.

The boards should be glued with hot glue.

The controller and wires are soldered together.

Wine cork can be an excellent solution to the issue of fixing the battery in the drum. We cut off a piece of cork so that the wires can freely pass inside. We insert batteries, followed by a plug, and then - plugs with a controller.

Next, you need to unsolder the switch, which is located on the side of the converter.

After you soldered the wires, you should insert the entire structure into the housing.

As a result, we get a working power bank, everything is pretty simple.