In this article we will tell you how to charge a mobile phone from a finger-type battery.

It often happens that when you are on the road you suddenly discover that the battery of your cell phone has run out, you need a power outlet to charge it, and you really need to make a call, and just be in touch.

What to do in such a situation? Thrifty people often have two batteries per phone, one on the phone, and the other either in the frog-type charger, or already charged and ready to be replaced. But they can also be disappointed when a second battery dies due to a long “trip to the Alps”. What to do?

You can overcome this problem. Our whole life in this modern age is "filled" with finger-type batteries, where only they are not? I suggest barbarously taking away a child’s toy in which are finger batteries and “sucking” energy out of them, while charging the cell phone’s battery. Just be careful, the child has a dad!

To charge a five-volt battery of a cell phone, you need only one finger-type battery of size AA, or AAA (in common people - pinky) and a special converter that produces as much as 5 volts from 1.5 volts. For the first time I met such a charger (naturally Chinese-made) in the Safari hunting store. An ordinary finger-type battery was inserted into a special cylindrical case, and a wire with a diverse set of adapters for various cell phones stuck out of the case. Naturally, there was no adapter on my phone, so I did not buy this miracle of technology. And my friend bought, and was satisfied. You insert the battery and in half an hour the phone is charged. Feel free to throw the battery into a garbage container, after making sure that it is not toxic and does not contain gold.
As you guessed, we will consider this scheme, and if desired, we can assemble it ourselves.

The converter is implemented on an integrated circuit MAX775 (MAX731). Its full analogue is our domestic chip KR1446PN1. There is only a slight difference, the MAX756 chip has a higher output current - up to 200 mA, and for the KR1446PN1 it is half as much - 100 mA. In addition, the efficiency of "Max" is higher than our counterpart. But ours is still better - cheaper! However, it is your desire to use which chip.

The man got rich, and according to the status and etiquette of his society, he is supposed to come to banquets with wives and lovers at the same time.

He brought his wife for the first time and tells: There he is on the sofa - my Boss, there she is his wife, and there she is by the window - his mistress. There is the head of a friendly corporation, his lover next to him, and his wife at the table. And there is our mistress standing at the fountain.

And the wife with enthusiasm in response: And ours is the most beautiful!

At present, they just do not try to come up with this chip. The power supply and charger work well. Everything else is like a cat who has nothing to do.

The circuit diagram is shown below. The converter circuit occupies a space not exceeding one finger element in size.

The circuit operates on the principle of a pulse converter with energy storage in the charging choke. This is a typical “booster” circuit with PWM stabilization of the output voltage. At the circuit output, a DC voltage of 5 volts. If the circuit is assembled correctly, then no settings are required.

The printed circuit board is equal in width and length to the dimensions of a standard AA battery. Board dimensions 13 x 51 mm. Flat brass springs are soldered to the edges of the circuit board to clamp the battery into them. These springs can be taken from the battery compartment of a "new" children's toy. No switch is used, the battery is inserted to charge the phone and is removed after it is fully charged. The converter on the KR1446PN1 chip works stably when the input voltage drops to 0.8 V, and on the MAX756 to 0.7 V. Therefore, instead of simple finger batteries, rechargeable finger cells can be used. When the voltage from 1.4 volts (the rated voltage of finger batteries) drops to 0.7-0.8 volts, then charging will simply turn off, and this residual voltage is valid for the battery, which can be used next time after the next charge.

The design of the charger uses standard installation elements: small-sized capacitors such as K50-35, I used imported (flattened) ones, which I removed from a burned-out computer motherboard. Choke - standard EU-24 with an inductance of 18-22 μH.

The circuit board of the device and the arrangement of elements on the circuit board are shown in the figure.

You can use anything as an output connector - a connector torn off from a “native” network adapter, or a friend’s adapter, “crocodiles” from a measuring device, etc. For the purpose of universality, I soldered a USB connector to the board. My “Android”, when its battery is discharged to 15%, before fully charging from this mobile device, takes about 1 hour (without talking on the phone) and one Energizer alkaline battery.

The technology does not stand still, and for seemingly simple and understandable tasks, new perfect controllers appear. Currently, I came across ncp1450, on which I made a similar converter, but in a smaller size.

People who spend a lot of time traveling, or for other reasons, are forced to use communication devices a lot, not being able to charge the phone’s battery as often as they need, are forced to look for ways out of this situation. Many find a solution to the problem of carrying several telephone batteries with them at once (this is not about smartphones with). But all of them sooner or later will be discharged and become useless. It takes too much time to charge each individually inside the gadget; it would be much more convenient to power one battery while the second is charging. In this regard, the question arises - how to charge the phone’s battery without a phone? You can make a device with your own hands, or you can buy a special device in the store for relatively little money. If you don’t really feel sorry for the battery of a smartphone, tablet, and a gadget is urgently needed, there are improvised ways to quickly charge the battery.

Battery box

It is possible to charge the phone’s battery directly by building some semblance of the currently popular mobile charge storage for gadgets - (this, by the way, is the best way).

To do this, take a special box for installing batteries that are interconnected and have pin leads out through wiring - you can get it on radio flea markets or in electronics stores, maybe it’s somewhere in the house. Several ordinary finger batteries are inserted there. You can output the contacts and directly connect them to the battery of the phone, observing the polarity, or you can solder the connector to the output hole and charge the cellphone itself.

Using Charges

How to charge the phone’s battery at home separately from it, directly from charging?

  To make a universal device for powering a battery from any old device for powering gadgets:

1. Find in the house any cluttered charger.
2. Cut the connector inserted into the socket, carefully strip the wires. Usually they are blue and red. Blue carries a charge with a minus sign, and red, respectively, plus.
3. Connect the metal ends of the wires to the phone’s battery, making sure that the polarity of the contacts coincides - they must be signed to the battery, fix the connection with tape or electrical tape.
4. Wait about an hour while the battery is charging, then it can be inserted into the gadget and used.

How else to check the polarity of the wiring?

Some charging wiring may not have these standard colors, but some other. In such a situation, you also need to somehow determine where the sign is. It is very easy to do. All you need is a glass of water, in which you need to dissolve a little ordinary table salt.

1. The bare ends of the wires must be lowered into this glass.
2. Connect the device to the network (the main thing is not to touch the water and the wires themselves, otherwise you can get an electric shock).
3. Trace around which wire the water began to boil and bubble. He is negative.

Charge from pieces of metal

It happens that you need at least a slightly charged phone battery somewhere in nature, where there are no old charges, or other similar devices. Can I charge the battery in this situation? Quite if you find more metal objects - pipes, corners and the like.

1. Take the items found and stick vertically into the ground.
2. Wrap with a wire, preferably made of copper.
3. The ends of this wire should be brought out like wires and connected to the battery.
4. Pour the metal part of the structure with alkaline liquid, which is needed as an electrolyte. As alkali, you can use solutions of salts or soda, some chemical means, if it is known that they include alkaline compounds. The more metal there is in the structure, the stronger the current.

To ensure that the battery lasts at least for a call, you can wrap its contacts with a thin transparent adhesive tape or other adhesive tape. Upon returning to the place, this will give a charge for a couple of minutes of work.

Heat

At higher temperatures, reactions begin to occur that take place when the battery is charging. Therefore, you can try to make up for a small part of the charge in this way - attach the element to something hot or just rub it with your hands for several minutes.

Deformation

The most risky way, which in almost all cases leads to a further battery malfunction, many have seen since childhood. Some bite finger batteries to make them work. Here the principle is the same. If you slightly throw the battery on a stone or beat it on some other solid object, a small charge will accumulate, which is enough for a couple of quick actions or short conversations.

Homemade Wireless Charger

To make it, you will need:

• thin, not more than half a millimeter in diameter, metal (ideally copper) wire;
• diode;
• some knowledge in the field of physics.

What then:

1. Make a flat coil of three dozen turns of wire.
2. Fix it with electrical tape or special glue on the telephone battery.
3. Take the diode and connect the battery contacts to the spiral through it.

Use ready-made tool

Of course, manufacturers of accessories for gadgets did not stand aside and took care of lovers of feeding batteries separately from technology. For such cases, there is a charge for the battery of a phone or tablet that feeds it directly, which is popularly nicknamed because of its characteristic shape.

Using it is quite simple:

1. Disconnect the device and remove the battery.
2. Decide where on the contacts is a positive charge, and where is negative.
3. Press on the edge of the frog lid to open it.
4. Inside the device there are two terminals that have a polarity signed.
5. Put the battery with the contacts to the terminals so that the "pros" and "cons" coincide.
6. Close the cover, which will automatically lock the battery position.
7. Connect the device to the network and check if the red light is on. If this did not happen, the battery was placed incorrectly, and you need to correct its position.
8. When everything is connected correctly, it remains to wait until the red color of the indicator changes to green - this means that the battery is charged, and the "frog" turned off the power.

There are many ways to charge the battery from any gadget, but it’s better to be prudent and have something with you that will allow you to safely replenish the charge, and do not resort to extreme methods at all or only in emergency situations.

Everyone can be in a situation in which there is no way to charge a mobile phone in the usual way. In such situations, ordinary batteries can come to the rescue, which are much easier to find, especially in emergency situations.

In order to charge a mobile phone with ordinary batteries, we need:
- 4 finger batteries;
- 2 ohm resistor;
- rectifier diode;
- A connector for charging and a box for batteries.

The author uses a night lamp as the basis for a future charger. In the lamp used by the author, all the batteries are connected in turn. Thus, the total voltage is 6 volts. To charge most mobile phones, 5 volt chargers are used, which is why we need to use a limiting resistor so that the phone’s battery does not fail from the voltage received.

As for the rectifier diode, then almost anyone will do. It is needed in order to prevent the batteries from recharging when they are completely empty. This diode can not be used only if you do not squeeze the entire charge out of the batteries to the bitter end. The author, for example, does not use it.

First of all, we disassemble the lamp. In the device that the author of the idea uses, there is a switch, which is also optional.

You can use a USB connection as a connector. From the USB cable we need only two wires - red and black, which are respectively the plus and minus wires.

We connect the resistor to the positive contact from the battery.

The other end of the resistor is connected to the diode, if any.

The minus from the battery, as well as the second end of the resistor, is connected to a USB outlet, observing the polarity.

From the side on the case we make a USB compartment. If desired, we additionally fix the connector with a glue gun.

Ways to charge the battery in the absence of a phone

Sometimes there are situations when you need to charge the phone’s battery in the absence of the latter. This is a rather problematic task if you get into such a situation for the first time. Who might need this? For example, those who often travel on long journeys and often are outside of electrical networks. Such people often have more than one battery for the phone. If the main one sits down, then they insert a spare and stay in touch. The question arises of charging spare batteries. After all, do not remove the main battery just to charge the second? If you disassemble the phone so often, the battery cover and mounts will quickly become unusable. Therefore, in this article we will consider several ways how to charge its battery without a phone.

First, consider the most civilized way to charge a battery without a phone. This will require universal charging, which the people nicknamed the "frog" for its characteristic appearance. If you constantly use several batteries for your phone, it is recommended to buy such a device. At the same time, read about how in normal mode.

Such universal devices consist of a battery clip, two contact pads made in the form of sliders, indicators (some models have an LED display) and a housing with a plug (or a power connector for connecting a network adapter).

Using the "frog" is very simple. You need to do the following:

• Find the positive and negative contacts on your mobile phone battery. They are signed as "+" and "-". Usually there are three contacts. The middle one is the output of the temperature sensor and you will not need it;
• Extend the sliders of the universal charger to the distance necessary to connect them to the positive and negative terminals of your battery;
• Open the clip and insert the battery. Push it all the way until the battery contacts touch the frog sliders. In this case, as a rule, indicators are turned on, indicating a proper connection;
• After that, connect the "frog" to the electrical network and charge. The universal charger will inform you about the full charge of the battery with the help of light indicators. That indicators of this or that device show, it is necessary to read in the manual to it.

Charge the battery directly from the adapter without a phone

In this case, you will need some kind of power adapter from a router, tablet or the same mobile phone.

Ideally, you need to find an adapter with the characteristics of 5 volts, 2 amperes. It will be just right.   If this is not the case, then you can use models with a nominal value of up to 9–20 volts and up to 4–5 amperes. Under these parameters, most network power supplies from laptops are suitable. It will only be necessary to put a resistor in the circuit, the resistance needed.

If you do not need an adapter, you can cut off the plug and take plus and minus from the wires. If you use the adapter to work with the standard device, then you should do differently. The photo below shows the plus and minus on the plug of the power adapter.

You need to take two wires, strip the ends and wind them to the plug with electrical tape. The positive wire is inserted inside, and the negative wire is attached to the plug shell.

After that, the return ends of the wires must be connected to the contact pads of the phone’s battery. To do this, you can use electrical tape or plastic ties. A resistor should be put in the gap of the positive wire.

It is best to take a tuning resistor so that you can change the charging current.   But you can calculate the necessary resistance and use a conventional resistor. It is recommended to limit the charging current of the mobile phone’s battery to 1.5 amperes. For example, you took an adapter with a nominal voltage of 12 volts. Then the necessary resistance according to Ohm's law is calculated as 12 volts / 1.5 amperes \u003d 8 Ohms.

Charging with finger batteries

This method is less common, but also has a right to exist. In this case, you will need a device for installing finger batteries (at least 4 pieces of 1.5 volts each) with leads. With a series connection of 4 finger batteries of 1.5 volts at the output we get a voltage of 6 volts.

The conclusions from this design are connected to the contacts of the phone’s battery in polarity, and so we charge. It is possible that the battery cannot be fully charged. This will depend on the capacity of the batteries.

In general, to fully charge the battery from an external battery, it is necessary that the capacity of the latter is twice that of a rechargeable battery. This rule is usually used when choosing external batteries for phones.

  The described method is suitable only for situations when you need to give the phone battery a small charge to make a call. It is not suitable for constant full charge. To properly charge the battery, you need it.

Hello! Today I’ll tell you how to charge a mobile phone with a regular 1.5 volt finger battery. Such a thing may be needed if he sat completely on the street, but an urgent need to make an important call. To do this, we need to assemble a simple circuit of a voltage converter of 1.5 volts (from battery) to standard 5 volts for phones and smartphones.

As you can see, to assemble this circuit we need to wind the transformer. The base of the transformer is a ferrite ring. You can get it from some power supply - from an old TV, from the motherboard. I took this ring from a burned out energy-saving lamp.

The copper wire for winding can be removed from the transformer. The thicker the wire, the better. I used a 0.5 mm wire.

The circuit board for this circuit does not need to be done. It can be assembled by hinged mounting, but it is possible as in this version - on the breadboard.

On the reverse side, the board does not look very neat, but it works fine. As a battery we take a new finger-type battery of any size. I used a size AA battery.

The battery voltage should be 1.5 volts, if it is lower, then the output voltage will be below 5 volts. After all, the circuit is simple, single-transistor and stabilization depending on voltage and current is not here.

Charger board in action

As you can see, the circuit works. The current strength of this circuit is about 150 mA, which is enough to charge a mobile phone. So this design can be used as a small Power Bank. But the phone will take a long time to charge and there may not be enough batteries to fully charge the phone. Therefore, if you are going to assemble a portable charger, I advise you to use ready-made converter cards with a current strength of at least 1 Ampere. Such boards can