A. A smartphone is a device that has become an indispensable communication device for all people. They are used to access the Internet and often for a long time. But smartphones have one drawback - time. battery life. In the best case, the battery will work without recharging for one day, and if you use it actively, then for several hours. This article and accompanying video show you how to make a powerful homemade Powerbank that can even charge your smartphone or tablet or a combination of both simultaneously.
You can buy the baby monitor, which is described at the beginning of the video, and all the components of the power bank in this Chinese store. Information on how to receive cashback (refund) in the amount of 7% of the price of all purchases is on our website. Download the schematic, board and other project files.
In order to improve battery performance mobile phone, portable ones were ordered charging device, which are popularly called power banks. But in its single form, such a device is not even half capable of charging a phone battery. And even three such devices do not provide a way out of the situation. Buying a powerful power bank is quite expensive. A normal powerbank, say, with a capacity of 10,000 milliamps costs 25-30 dollars. Considering this and the long waiting time for the parcel, it is easier to make your own option.
Description of the power bank circuit
The powerbank circuit consists of three main parts. This is a lithium battery charge controller with an auto-shutoff function when fully charged; battery compartment with parallel-connected 18650 lithium-ion batteries; 5-10 amp power switch from the computer power supply; a boost converter in order to increase the voltage from the battery to the desired values of 5 volts, which are needed to charge a phone or tablet; USB connector to which the device to be charged is connected.
In addition to its simplicity and low cost, the presented circuit has high output current values, which can reach up to 4 amperes and depends on the rating of components such as a field-effect transistor, a Schottky diode at the output and inductance. Chinese analogues are capable of providing an output current of no more than 2.1 amperes. This is enough to charge a couple of smartphones at the same time, and our power bank can handle 4-5 smartphones.
Let's look at the individual components of the structure. The power source is 5 parallel-connected 18650 batteries from a laptop. The capacity of each battery is 2600 milliamps per hour. The housing used is from an adapter or inverter, but another suitable housing can be used. We will use a charging board purchased as a charge controller. The charging current is about 1 ampere. You can also take a ready-made inverter that will increase the voltage from the battery to the required 5 volts. It's very cheap. Maximum output current up to 2 amperes.
Circuit assembly
At the first stage, we fix the batteries and fasten them together using a glue gun. Next you need to connect to battery controller to check how the charging process is happening. You also need to find out the battery charge time and understand whether auto-shutdown works when fully charged. Everything is labeled in detail on the board.
You can charge from any USB port. The indicator should show that charging is in progress. After 5 hours, the second indicator lights up, which means the charging process is complete. If a metal case is used, the batteries should be additionally insulated using wide tape.
One of the main components of the circuit is a step-up dc-dc converter, an inverter - voltage converter. It is designed to raise the voltage from the batteries to 5 Volts needed to charge the phone. The voltage of one battery is 3.7 volts. Here they are connected in parallel, so an inverter is needed.
The system is built on a 555 timer - a field-effect transistor and stabilization of the output voltage, which is set using a zener diode vd2. You may have to pick up a zener diode. Any low-power zener diode will do. Resistors of 0.25 or even 0.125 watts. Inductor L1 can be removed from the computer power supply. The diameter of the wire is at least 0.8, it is best to make 1 millimeter. The number of turns is 10-15.
The circuit contains a frequency-setting unit that sets the operating frequency of the timer. The latter is connected as a square pulse generator. With this selection of components, the operating frequency of the timer is about 48-50 kHz. Gate limiting resistor R3 for a 4.7 Ohm field effect transistor. Resistance can be from 1 to 10 Ohms. You can replace this resistor with a jumper. Field effect transistor of any average power with a current of 7 amperes. Field grasses from motherboards. Small reverse conduction transistor vt1. A kt315 or other low-power reverse conduction transistor will do. Rectifier diode - it is advisable to use a Schottky diode with a minimum voltage drop across the junction. Two containers serve as a power filter.
This inverter is pulsed, it provides high efficiency, high output voltage stabilization, and does not heat up during operation. Therefore, there is no need to install power components on the heat sink. If there are difficulties with Schottky diodes, then you can use diodes that are in computer units nutrition. Dual to-220 diodes are found in them.
The photo below shows the inverter in assembled condition.
Can be done printed circuit board. There is a link in the description.
Testing a 5 volt inverter
We check the inverter for functionality. The smartphone is charging, as you can see, the charging process is in progress. The output voltage is kept at 5.3 volts, which fully complies with the standards. The inverter does not heat up.
Final assembly into the body
We need to cut out the side walls from a piece of plastic. The charge controller has two LED indicators that show the charge percentage. They need to be replaced with brighter ones and displayed on the front panel. There are two holes cut out in the side wall for micro USB connectors, which means you can charge two devices at the same time. There are also holes for LEDs. A hole for the controller, that is, for charging the built-in batteries. A small hole will also be made for the power switch.
All connectors, LEDs and switch are fixed with a glue gun. All that remains is to pack everything into the case.
A USB tester is connected to the output of the device. It can be seen that the output voltage remains firmly at 5 volts. Let's connect mobile phones and try to charge them from a homemade Power bank. Two smartphones will be charged at once. The charging current jumps to 1.2 Amperes, the voltage is also normal. The charging process is progressing successfully. The inverter works flawlessly. It turned out compact and, most importantly, stable. The circuit is easy to assemble; familiar components are used.
Modern smartphones and tablets consume a lot of energy, so the battery must be charged frequently. The solution to this problem is purchasing an external battery. You can make a Power Bank with your own hands. Self-assembly has advantages and disadvantages that must be taken into account before starting work.
An example of a DIY power bank.
Advantages and disadvantages of homemade products
The positive qualities of a homemade device include the following:
- Relatively low cost. Capacious external batteries cost at least 5 thousand rubles. Cheaper models do not meet the user's needs or quickly fail. If you have the necessary materials, you can assemble an inexpensive, powerful power bank yourself.
- No difficulties during repairs. The device has a removable housing, making it easy to dismantle and replace parts. In addition, the person who assembled the device is familiar with the type of electrical circuit.
- Possibility to obtain the required capacity. At home, you can assemble a 6000 mAh battery.
- Environmental Safety. It is good for the environment to reuse lithium-ion batteries with faulty controllers.
- Non-standard design. Strange appearance The housing is considered attractive by some users.
Disadvantages of manual assembly:
- The complexity of the process. The power bank may take several days to produce. To assemble the device correctly, you need to have some skills.
- Unattractive appearance. Homemade device almost impossible to make compact.
- Lack of some materials at hand. Some parts are difficult to find even in specialized stores.
- Short service life.
- Lack of LED indicators. These details help you track your phone's charging progress. The shutdown button may also be missing, which causes inconvenience during operation. Adding keys to electrical circuits complicates the assembly process.
- Failure of the battery being charged. This risk is present when using any power bank, but when assembling it yourself, this probability is higher.
- High cost. This happens, for example, when using a charge controller.
By the way, read this article too: Onda M2 new mini-computer for $200
Manufacturing materials
You can make a Powerbank with your own hands from any type of power source. The most commonly used materials are:
- old lithium-ion batteries of the required capacity;
- unnecessary batteries from laptops;
- finger batteries.
Regardless of the type of base, you will need a charge controller and a USB connector.
All parts must be in good working order.
Components of a Power Bank battery.
From phone batteries
The use of this method helps to create a capacious, convenient device. To make a power bank, you will need 6 high-capacity batteries. The assembly is done like this:
- 3 batteries are placed in a stack, which is secured with tape. The contacts are directed in one direction. The same steps are repeated for the remaining batteries. When gluing, avoid getting tape on the terminals.
The device, assembled from telephone batteries, allows you to charge the gadget 4-5 times. For charging powerful smartphone or a tablet it will not work.
From AA batteries
It is not difficult to assemble a power bank from finger batteries. The resulting device is no different large capacity and reliability. However, the device is suitable for emergency charging of the gadget. They assemble it like this:
- Cut off the tops of 2 matchboxes and glue their bases together.
- Each box contains 2 AA batteries. The poles point in one direction.
- Stationery staples connect batteries located in different boxes. When combining terminals, polarity is taken into account. The staples are fixed with wire. Adhesive tape is not recommended as it may cover the contacts.
- The resulting structure is placed in a plastic container. The boxes are glued with hot glue. The location where the connector will be installed is determined in advance in the case. A short cable is connected to the USB port. After this, the connector is securely fixed.
After completing all the steps, you get a small power bank that you can carry in your bag.
Homemade Power Bank from a AA battery.
This method allows you to create a capacious and powerful external battery. It can be used as a charger for energy-intensive gadgets - laptops, tablets.
The elements must be in good working order. Old batteries with a burnt-out controller will do. The assembly is done like this:
- Prepare 8 18650 batteries. Find a container that will serve as a housing. A hole is made in it for the connector and the power button. This power bank can be supplemented with keys.
- Assemble blocks consisting of 4 batteries. The positive terminals should face one way, the negative terminals the other.
- Both blocks are placed in a plastic container and fixed with hot glue. The structure is soldered to the system for turning off the car charger.
- The USB output is connected to batteries and a switch.
Power Bank from car charging.
The capacity of a homemade power bank is enough for several charging cycles of a powerful gadget. Start charging by connecting the tablet and pressing the power button. Stop the process by turning the relay to the “Off” position. After this, you can disconnect the gadget.
From a flashlight
An external battery can be created from a simple flashlight. For this you will need lighting fixture consuming 3.7 volts, converter, connector and controller. The available 3.7 V needs to be converted into 5 V needed to charge the smartphone. The power bank is assembled as follows:
- They disassemble the flashlight and find a resistor with an LED. The latter is disconnected.
- Remove the metal contact that was used to charge the flashlight and replace it with a voltage converter with a USB connector.
- Both contacts of the flashlight battery are soldered to the controller. The controller terminals are marked with “-” and “+” signs, which are taken into account during assembly.
- The resulting structure is connected to the converter. This part is connected to one of the switch contacts.
- The converter is checked with a multimeter. If there is no voltage, the part is combined with another contact. The device must function.
- The controller and converter are glued to the case, then the battery is installed.
After assembly, you get a convenient and interesting power bank for your phone.
Everyone brainiacs, Hello! I suppose you all belong to that part of the world's population that uses smartphones, and I think over the past couple of years you have replaced them several times with more advanced ones. All “outdated” smartphones have lithium-ion batteries, which are not possible to use in new models, and thus you are left with good, but useless batteries... Is this true?
Personally, I have accumulated three phone batteries (and I did not change the phones because the batteries were faulty), they did not heat up or swell, and they can be used to power some gadgets. The capacity of an average battery after 2 years of use is about 80% of the original, this is exactly the period during which I usually purchase a new one brainsmartphone. And if you think about the efforts to obtain raw materials, the production of the batteries themselves and the costs of transportation...
All things considered, it would be a real shame to let them slowly "die" or simply throw them away. In this brain article And video I'll tell you how with your own hands do homemade, which allows you to “give new life” to batteries from old phones, that is, make an external battery for gadgets, also known as POWERBANK.
Step 1: Materials
Well, let's start with what you need to create your own external battery. Materials needed:
- lithium-ion battery,
- charging and protection board for lithium-ion batteries, designed for 5V, maximum input current 1A (the less, the longer the “second life” of the battery will be),
- DC/DC boost converter with output values of 5V and max. 600MA
wires, - several pin connectors,
- stationery clip,
a piece of acrylic, - screws,
- and a switch.
You will also need:
- a pair of pliers,
- stripper,
- soldering iron,
- and a glue gun,
- and also a drill and a drill.
Step 2: How do the boards work?
First, let's take a look at the charging and protection board for lithium-ion batteries. Its three important functions are charging, overcurrent protection and undervoltage protection.
Lithium-ion batteries charge according to a specific pattern - when they are almost fully charged, their current consumption decreases. Brain board recognizes this and as soon as the battery voltage reaches 4.2V, it stops charging. At the output of the board there is a protection circuit that prevents overcurrent and excessive undervoltage. Modern telephone batteries already have such protection built in, but in this case homemade This board will allow you to use unprotected batteries that can be found in older laptops. The charging current of the board can be adjusted using a resistor, and it should be within 30-50% of the rated battery capacity.
The DC converter converts the battery's DC voltage into a square wave and passes it through a small coil. Due to induction processes, a higher voltage is generated, which is converted back to DC and can be used to power gadgets designed for 5V.
Now, more or less knowing what we are dealing with, we can begin the actual assembly brain games.
Step 3: Design
Before you start creating the housing for homemade products, measure the components and make a drawing. So in my brain structure the battery will be secured using a stationery clip, which is screwed to the case, the boards will be located on top of each other, the input/output contacts will be on top in the upper part of the case, and the contacts going to the batteries will be on the bottom.
Some batteries have a non-standard position of the polarity of the contacts, so this “non-standard” must be taken into account in our device, that is, we need to add pin connectors. To do this, take a connector with three pins and tear out the middle one, and bend the pins themselves on one side to make it easier to attach them to the battery contacts. Or take a connector with four pins, connect the outer ones to the positive terminal, and the middle ones to the negative, and thereby change the polarity of the contacts by simply connecting the battery to the left or right pair of pins.
Step 4: Making the Case
Now let's start assembling the body. To do this, take a ruler and use a sharp knife to mark the lines, scratching them about 10 times, so that you don’t have to put a lot of effort on the workpiece and don’t use the ruler anymore. Having scratched the lines to a sufficient depth, we apply pliers to them and bend the workpiece until it breaks along these lines. Having “broken” all the necessary parts in this way braincase, we clean them and adjust them to each other. Then we attach them to a stable surface and, using a drill, make holes and slots for screws, a switch, inputs, outputs and pin connectors.
Step 5: Circuit Assembly
Before you begin assembly brain devices First we assemble the electrical circuit, and focus on the presented diagram. A small switch here serves to turn the converter on/off direct current.
Step 6: Final Assembly
Using a glue gun, we glue the boards to each other, and then to one of the body parts. Next, we glue the entire body and screw a stationery clip to it.
We connect the battery through the pin connector and try homemade In action. If it does not work, then connect the charging cable.
Step 7: Use!
Well, now your old phone batteries are back in business!
The version of the case I proposed is of course not ideal, but it will do for demonstrating the whole concept. I can even bet that you will come up with a much better solution :)
That's all, everyone brain success!
External batteries (Power Bank) are used to charge portable mobile devices. They are convenient to use on hiking trips or on vacation, when there is no way to charge your mobile phone from the network or computer. But what if you live far from specialized stores or simply don’t want to spend money on buying an external battery? In this article we will tell you how you can make a Power Bank yourself from available materials.
How to make a Power Bank with your own hands?
To make a homemade external battery, you do not need to buy any expensive parts; all of them can be found at home.
So, we will need:
Nickel AA batteries, 4 pcs.
. USB connector.
. Air freshener bottle.
. Film box.
. Wires.
. Matchboxes, 2 pcs.
. A jar for vitamins (or any other appropriate size).
. Staples.
. Metal wire.
Let's start making!
1. We glue the matchboxes together by cutting off and bending one of the walls of each of them (as in the photo). We put batteries in them.
2. Using staples we make contacts with reverse side boxes and connect them with wire.
3. The result is a design with a voltage of just over 5 volts, which is quite enough to charge a mobile phone. We place it in a film box and seal it so that nothing dangles.
4 . We cut off the bottom of the vitamin jar, make a hole in it and insert a USB connector (if there is no vitamin jar, you can use any other lid, the main thing is that it fits as a lid to the air freshener bottle). Solder the USB wire to the USB, connect it to the battery and close the box.
5. To ensure that our Power Bank lasts a long time and does not fall apart at the first shake, we place it in an air freshener bottle.
Since portable devices are currently the most widely used electronic devices, such as tablets, netbooks, cameras or smartphones, then a big problem has arisen with ensuring that these devices are recharged, since often some people during the day do not have the opportunity to recharge the battery of their equipment from electrical network. This problem was successfully solved thanks to external batteries or, in other words, power banks, thanks to which it became possible to recharge your device while on the street, in nature or in transport.
Of course, most power banks are now inexpensive, but if you want, you can easily create one yourself. Its manufacturing process Provided you have the necessary components, it will not take much time. Two or three hours will be enough. The main thing is that you have the desire to go through all the required steps, and, in addition, your ability to solder and understand electrical circuits will be useful.
If you are interested in how assemble a power bank quickly and without any hassle, then you can watch this video on the Internet.
Schemes for developing and creating power banks with your own hands
From cell phone batteries
One of the most simple ways . For this purpose you will need to perform the following procedure:
Power bank from a flashlight
To make a power bank with your own hands using a flashlight, you need to prepare the following items: the flashlight itself with a battery of three point seven volts; charge board; a voltage converter that can turn a flashlight voltage of three point seven Volts into five Volts, always with a USB output.
Procedure for creating homemade power bank is as follows:
Power bank on AA batteries
In order to make such an external battery, take two matchboxes, bend one of the walls of each of them, and glue these boxes to each other. Then put two batteries in each of the boxes. Use staples to securely connect the boxes to each other and additionally wrap them with wire. Choose a case for your external battery. It will be very good if the distance between the matchboxes and the body is minimal or completely absent.
After that, find a large plastic jar that your power bank can fit in, and cut a hole in its lid where you can attach it. USB connector. Solder a wire to this connector and connect it to your power bank. Place your external battery in the jar and close the lid. Now the production of the power bank is completed, and you can use it to meet your own needs.
