Devices such as Bluetooth headsets, MP3 players, and similar miniature gadgets use very low-capacity batteries. Maximum 3-4 hours of listening to music, no more. No matter how much I repaired and disassembled them, they all have batteries from 40 mAh, and no more than 350 mAh. This is very little. And if your smartphone has a powerful battery, then taking a large and heavy Power Bank with you on the road to recharge your player or headphones is not very cost-effective. Therefore, I propose to make a compact external charger from used disposable evaporators. The product that we will receive in the end will have a capacity sufficient for 3-4 headset charges and 2 MP3 player charges.
The device will have dimensions no larger than a disposable lighter, which is very convenient to carry with you.
Will need
- Disposable evaporator (2 pcs).
- Charging module for 18650 battery.
- Soldering iron, tin and flux.
- Wire cutters.
- Engraver with cutting disc.
- Secondary glue.
- Hot glue.
- Scissors.
- Needle file.
- Insulating tape.
Making a charger
First you need to select two evaporators with identical batteries.Preferably with the same capacity and shape. I didn’t have any problems with this - knowing about my passion for all kinds of assemblies and homemade products, these disposable evaporators are constantly brought to me.
The manufacturers of these devices are very short-sighted in wasting lithium-ion batteries by placing them in disposable gadgets. In addition, these devices, for the most part, are sent to landfills after use, thereby poisoning the soil. So isn't it better to give them a second “life”? So, if you yourself are not into such a dubious pleasure as smoking these things, then perhaps among your friends there is someone you can ask about such unnecessary devices. We disassemble two identical evaporators and cut off the wires from the battery with wire cutters.
All other innards can be discarded. We also leave the body in the color you like. We take the charging module and try it on the case.
On the side where the battery was removed. If the module does not fit into the body, then mark with a marker the place that needs to be cut down, and cut down this place.
Again we try on the module in a new place.
If everything is fine, you can start assembling the battery. To do this, glue both batteries together with second glue. Plus to plus, and minus to minus.
In the same way, in parallel, we solder them:
Let's try on how they fit into the body. If everything is in order, then you can solder a charging module to the resulting double battery.
Each battery has a capacity of 280 mAh. For batteries soldered in parallel, the capacity doubles - 560 mAh. So, we strip the ends of the wires, tin them, and solder them according to the polarity indicated on the module and batteries. Here you need to be extremely careful; If you get the polarity wrong, the module will instantly fail. We check the resulting filling of the future charger.
The indicator on the module glows blue when energy is being released; when charging the charger itself, it will glow red. Now we isolate the battery contacts with a piece of electrical tape, and push the whole thing inside the case.
In those places where the fiberglass base of the module touches the charger body, add a drop of second glue. We seal the remaining cracks using a hot glue gun.
As is usually the case, I ran out of hot glue at just the right moment. I had to improvise with the leftovers... We wait until everything hardens and dries, and check it again. Possible on several gadgets.
Everything works like clockwork. It charges itself from the power supply and transfers charge to other devices. We charge the new device according to the indication LEDs on the module and, together with a short USB cable, you can put it away in some pocket of your everyday outerwear. At the right moment, you will definitely remember him!
