ultra small portable power supply - battery management unit
A few days ago, after a very busy time, I finally finished a new project.
My main lab is in our stairwell and has almost all my equipment, but sometimes I like to sit in the living room at my desk, especially with arduino or raspberry.
But my living room is not my lab, so there is no place to make a loud noise. . . tools.
OK, I don't think my wife will be happy when I move the lab to the living room.
So I need a small PSU for some testing. . . .
We're here. . . Key Facts:1.
This is a fully battery powered desktop PSU with a very small form factor. 2.
All the parts add up to about 40 euros, very cheap.
0-really good. 20V 0-2A4.
It's easy to put some parts together, that's it, hey, I made it so you can do it too. 5.
It shows the input voltage, set the amplifier, output power 6.
It can work as a constant current or a constant voltage.
It can store up to two set voltages and currents.
My signature wooden box design is done with knives and glue: Battery Pack: 16, 8 V, 2500 mAh, 42 WhOutput: 0-20V, 0-
2 ASize: 11, x 12 cm x 5 cm (
I'm from Germany, we use cm, sorry guys should go shopping around 5 "x 5" x2 "and send me chocolate.
The first picture shows the more special parts you need in the project, maybe you have to buy them.
DC/DC boost converter [
Link of DC/DC module]
After I contacted banggood, they now have the original module I used in the project at a very reasonable price, less than $5, thanks to the excellent service from banggood's friends. Battery Pack [link for bms]
The first part is the battery pack I made with a 4x16850 lithium ion battery (4,2V 2500mAh)
I just have a broken power box because the lithium ion battery is a bit tricky and I bought a BMS (
Battery Management System
3 or 4 cells.
How to weld BMS to the battery found in the BMS module specification.
Boost converter [
Link to DC/DC converter]
My battery pack has an output of about 12 V to 16, 8 V, but for the last module I need about 23 V, so I'm just raising the voltage with this module. PSU Modul [
Link to the Psu module]
Here, all magic happens, just power it with 23 V and you can play without heat --
The sink is needed because it is a DC/DC converter and of course the voltage of the classic linear converter is cleaner, but not very useful for some battery powered devices. 1.
From the boost converter to the PSU module 2.
From battery pack to charging port 3.
Switch between the battery pack and the boost converter.
Red binding posts from the PSU module to front panel 5.
The black binding post of the PSU module to the front panel 6.
Oh damn, no black wire on the picture is made of 4mm plywood because it is easy to use and does not require any special tools.
The size in the brilliant hand-painted blueprint is the size of 4mm plywood, if you use other materials, you have to make sure you change the other size as well, otherwise it doesn't fit, or you just need to design it yourself.
After I cut all the parts from a piece of plywood, I just glued it together and usually I use some tape to make sure it doesn't fall off when it's dry.
Only the lid that I don't have glue, which will be connected with some very small screws.
My case doesn't need to be perfect, but I like it to be smooth, so I will polish them clean before I draw them, which is also good when you work less precisely, because the knife is not a laser cutter or cnc, or just I am always in a hurry.
I just have some leftovers in brown wood color so all my items have this paint and I love it and it looks a bit retro too, after finishing the paint I only waited for a few minutes, then put some beeswax in the basement.
Just buy some sticky silicon bumpers below to make the psu more stable on the table.
To be honest, before I build the case, I made a proof of the concept prototype, here I put all the parts together, which is also useful for building the case and understanding what space I need
In this photo, you see my electronic load, that's why I came to the Instructure, I saw the Instructure of this electronic load and built it, when you build the PSU, there's nothing more useful than the electronic load
Link to large arduino control electronic load [link]
Electronic load module]link]
Hey, we're close to the last step, a cool device that has hopefully worked.
Here you can see how I place all the parts in the box.
You can also find another wonderful and unique technical drawing 100% made by myself, using it for all the wiring, but be careful, it's quiet a lot in this small box
Of course, I used to charge the battery, I used my desktop PSU in this work, I just set the constant voltage of 16, 8 v and constant current of 1 amp.
Start it and it should work.
As far as I know, congratulate you on having the first battery-powered bench performance PSU on hand and can start with some projects.
For example, power the raspberry with it or whatever you want.
Here I will show you the results of a small test I did with PSU to check the noise I tested with about 15 watts of output power. Setup-
PSU and my battery powered PSU-
Both are set to 10 V-
Electronic load set to 1,5-
DSO 100mv/DivYou can see on the second picture, I have more noise on the battery powered PSU can't find any problem.
Hey, I already said I was busy at the beginning.
So she's the reason my little girl "made in China" but now she's 6 months old so it's time to train her on the computer, I think she can start making things with me.