How to make a fast charging powerbank
Hello, dear readers and homemade products!
The times when cell phones were just phones, and could safely hold a charge for a week, are long gone. Modern smartphones can do a lot, and with such opportunities, they eat very well. Having completely clogged the stomach at night, the supply of these animals is rarely enough for a full working day. As a result, you either have to carry a charger with you and look for an outlet, or take a power bank.
Almost all new models of smartphones and other digital devices have fast charging technology. Since higher voltages and currents are used, increased protection requirements are needed.
In this article, the author of the YouTube channel “Sorin – DIY Electrical Nerd” will show you how to make a portable battery (powerbank) with fast charging support (AFC, QC2.0, QC3.0, FCP/SCP).
This project is very versatile, and is built on the basis of several modules. It can be easily repeated at home, with a little experience in soldering.
Materials needed for homemade.
– BMS 6S 24V 40A Battery Protection Board
– NCR18650B 3.7v 3400mAh Batteries
– Three-stage charger for Li-ion batteries
– Adjustable buck module LM2596
– USB buck converter for fast charging QC3.0 QC2.0
– LED battery indicator 7S 6S 3S 2S 1S
– USB tester (voltmeter + ammeter)
– Plastic sealed box with transparent cover
– Battery holder for 18650 batteries
– Heat sinks with heat conductive adhesive tape
– USB socket, power connector, switch
– Wires, solder, 3M insulating tape, heat shrink tubing. < br> Tools used by the author.
– Laboratory power supply < br> – Universal charger OPUS BT-C3100
– Electric soldering iron with temperature control
– Digital multimeter
– Screwdriver with bit set
– Dremel, hot glue gun
– USB charging cable.
Manufacturing process.
So, the master will use this set of modules.
You can also use a module with two or four USB fast charging ports.
First of all, the wizard will demonstrate the operation of the fast charging module by submitting to its input 21.4V from a laboratory power supply.
A USB tester is connected to the module output. As you can see, the module reduces and limits the output voltage to 5V.
When a smartphone that supports the fast charging function is connected, the module will recognize it, and raises the output voltage to 9V. The current in this case is 1.41A.
An adjustable step-down module on the LM2596 will reduce the battery voltage to 5V, so that you can charge regular gadgets.
Another converter is used to connect devices with fast charging function. The voltage at the input of such a module can be from 6 to 32V.
Energy will be stored by an assembly of six series-connected (6S) NCR18650B batteries. These batteries are convenient because they already have welded conductors in the form of metal strips.
First, the author installs new 18650 batteries in the charger, and performs three automatic discharge-charge cycles.
Two L-shaped sections are assembled from the battery holders.
Batteries are inserted into them, and the polarity must be alternated so that it is convenient to connect them in series. Be careful, the tapes are very sharp and you can easily injure yourself.
Next, you need to solder the tapes from negative to positive. This should be done quickly to prevent overheating and damage to batteries.
Now you need to check the voltage produced by the charged assembly using a multimeter. It is 25V. The assembly capacity is the same as that of a separate cell – 3200 mAh, and the total energy is as much as 70 W.
Extra connectors can be cut to fit in building.
Alternatively, you can wind up the batteries with electrical tape, but ventilation will deteriorate and cooling.
There will be a charge to manage the charge and protect against abnormal situations BMS 6S.
A diagram of the connection of all elements is shown in the following picture.
< img class = "aligncenter" alt = "How to make a fast charging powerbank" src = "https://usamodelkina.ru/uploads/posts/2021-02/1614450287_pwb-129.jpg"/> By soldering the wires to the assembly, the master insulates the open contacts without closing the gaps between the batteries.
Then the wires are soldered to the terminals on the protection board and charge management BMS 6S.
Strips are glued to the bottom of the board and the edges of the holders before installation in the case made of foamed double-sided tape.
The following charger will be used to charge the power bank.
When connecting a load of resistors, and currents of 1 – 1.5 A, no voltage drop is observed. It drops quite a bit (to 24.7V) at two amperes.
All components will be assembled in a sealed plastic box with a transparent lid. Perhaps it is a little too big, and you can find a more compact version.
< img class = "aligncenter" alt = "How to make a fast charging powerbank" src = "https://usamodelkina.ru/uploads/posts/2021-02/1614450241_pwb-163.jpg"/> Further, with the help of a knife and a dremel, excess plastic elements are removed, and the surfaces are leveled.
Windows are also drilled and cut through to install the power button, connectors.
The master uses a simple USB socket for the port dedicated to normal charging. Data transfer contacts Data + and Data- are closed with each other, and power wires are soldered to Vcc and GND.
The board with the slot is fixed in place with a glue gun.
The battery assembly locks into the housing.
Two wires are soldered to the positive contact of the power connector at once, for easy connection .
To measure voltage and current at the fast charge output , the master uses the module from the USB tester (voltmeter + ammeter).
He cuts out a part of the transparent lid and fixes it on the LED indicators. This will make the readings easier to see in bright daylight.
The tester is connected directly to the output of the fast charging module.
The standard connector of the tester will have to be removed and the modules connected with wires, since there are quite large losses at the transitions in the connectors. This can be clearly seen if you enable several testers sequentially, and at the end add a load.
It is also advisable to glue heatsinks to the microcircuits with hot melt glue, or take a heatsink with heat-conducting adhesive tape. It is important that the metal surfaces of the radiator do not touch other electronic components or close them.
You need to solder the power and data wires to the contacts on the fast charge board. This is necessary for communication between the board and the charged device.
Remains connect all modules according to the diagram, and fix them on double-sided tape.
Terminals on the breaker are heat shrinkable.
Having connected a load to the normal output, the author sets the voltage to 5.05V by rotating the trimmer resistor on the LM2596 step-down module.
The wires from the fast charging module are soldered to the tester input.
Another radiator can be installed on the inductor, it also heats up.
To control the battery charge level, the master connects such an LED indicator. Its wires are connected to the battery outlet after the switch.
< a href = "https://usamodelkina.ru/uploads/posts/2021-02/1614450303_pwb-388.jpg" rel = "prettyPhoto">
A 3A fuse is installed in the break of the positive wire from the battery. The fuse body is protected by a heat shrink tube. The end of the wire is soldered to the B + terminal of the BMS board.
< a href = "https://usamodelkina.ru/uploads/posts/2021-02/1614450314_pwb-403.jpg" rel = "prettyPhoto">
It remains to fasten the cover with regular screws, and the original portable charger is ready.
< img class = "aligncenter" alt = "How to make a fast charging powerbank" src = "https://usamodelkina.ru/uploads/posts/2021-02/1614450331_pwb-411.jpg"/> The gadget is connected to the device via a charging cable .
Different models of smartphones use different fast charging modes. This can be clearly seen from the readings of the voltmeter and ammeter.
The author decided to discharge the power bank by connecting a light bulb as a load. The BMS board disconnected the battery when the voltage dropped to 16.5V.
A full charge with an initial current of 2A takes about three hours.
All modules together with indicators consume about 20mA.
< a href = "https://usamodelkina.ru/uploads/posts/2021-02/1614450358_pwb-466.jpg" rel = "prettyPhoto"> For those who prefer a ready-made product: PowerBank from Baseus with fair capacity.
I recommend the large GreatWall store of electronic modules and devices at great prices.
Thanks to the author for the master class on making a power bank with a fast charging function.
Good mood, good health, and interesting ideas to everyone!
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The author's video can be found here. < br>