Powerful do-it-yourself usb charging in a car. USB connector in the car

Baubles, or, as they are also called, friendship bracelets came into the world at the suggestion of hippies. Children of flowers put a global meaning in their baubles - in addition to the idea "all people are brothers" and its confirmation with these bracelets by the color of baubles, one could learn about a person, if not everything, then a lot. For example, the combination of yellow, orange and blue colors told that a person is keen on esotericism and spiritual development. However, gradually the sacred meaning of the baubles disappeared, and they became a simple decoration for the "free in spirit" people.

Weaving baubles is not only fun, but also useful: working with your hands, plus the ability to create and create, plus repetitive actions - all this not only improves mood, but also helps to relax and move away from everyday activities. For beginners, this effect is possible when weaving simple baubles with multiple repetitions of actions. To weave your first bauble you will need:

• 7 threads (floss or iris, 100-120cm each);
  
• scissors;
  
• duct tape, tape or pin.
  

1. Arrange the threads in the order in which the colors will go. It is best to take contrasting bright threads - all the knots will be clearly visible on them. Tie an ordinary knot and secure the bauble with duct tape (on hard surfaces), tape (keep in mind that it can stick to and tear threads), or safety pins (good for outdoor conditions).

   

   
   
2. Take the two leftmost strands and put the leftmost red thread on the right light thread from left to right.

   

   
   
3. Pass the end of the thread from bottom to top into the loop formed. Tighten the knot by pulling the red thread up.

   

   
   
4. The knot should be double, that is, you need to tie it on the same threads twice. The red thread should be on the right after tying.

   

   
   
5. Tie the second red thread with a red thread in the same way as in the first paragraphs. In a row, these will be the second and third threads from the left. In the same way, continue to tie the whole row with this thread - in the end, it will be on the far right.

   

   
   
6. So, the red thread turned out to be on the right, we go back to the left edge. Take the two strands on the far left again. Now there is a light thread on the left - she needs to tie the second row. Put the light thread on top of the red thread from left to right, and thread it through the loop from bottom to top.

   

   
   
7. Tighten the knot by pulling on the light-colored thread. In the first photo there is a regular knot, in the second - a double one. Feel the difference: after tying the second knot, the thread is automatically on the right.

   

   
   
8. Braid the row with a light thread and leave it to the right.

   

   
   
9. By analogy, continue to weave the bauble until its length is equal to the length of the wrist, or about 17-20 cm.

   

   
   
10. When the bracelet reaches the desired length, braid the remaining braids from the bottom and secure with a knot. Do the same on the other side, having previously untied the fixing knot.

    

    
    
11. Trim off excess ends. You can admire your creation!

    

    
    

Before you start weaving baubles out of threads, remember: weaving baubles is very inspiring, and it is almost impossible to stop weaving forever. Many people say that during weaving, their breathing becomes smoother, their thoughts are laid out on the shelves by themselves, and uniform knots in the rows increase their mood. The person who is given fenku also feels very happy. Therefore, weave, improve your skills, give baubles to your loved ones, and maybe over time the world will really become a little brighter and better.

Fenichka is a bracelet made by hand from beads, threads, wool or leather. Historically, the art of weaving such bracelets originated in the tribes of North American Indians, where they were decorated with feathers, beads and embroidery. Baubles gained immense popularity in the 60s of the XX century with the development and spread of such a subculture as hippies. Then these gizmos began to include not only thread bracelets, but also headbands, decorative bags for documents and trifles.

Initially, a bauble is a symbol of friendship and sincere sympathy. They were given as a recognition of eternal devotion, as a symbol of involvement in something, and even as wedding bracelets.

Moreover, even the combinations of colors and patterns had their own meaning, which was easily interpreted by those who knew the designations. Therefore, the colors of the future product were selected carefully and taking into account the personal qualities of the person for whom the bauble was being prepared as a gift. Bracelets were made for friends, relatives and loved ones, and it was considered bad form to weave them to oneself.

In principle, baubles can be weaved from any convenient improvised material, however, being one of the special types of macrame, they are more often made from woolen threads, iris or floss.

Thread baubles can be weaved in two ways - straight and oblique weaving. The first is considered the simplest, but often it is with him that more questions arise. You can learn how to weave beautiful oblique weaving patterns from special patterns, which will be discussed a little later.

The second, direct weaving, requires great concentration and dexterity, however, using all the same patterns, this look can be used to weave a beautiful personalized bracelet, a bauble-picture or your own original print. As patterns, patterns for cross stitching, or independently drawn on a notebook sheet, are well suited.

Direct weaving involves two types of knots - direct and reverse. Moreover, the thread of the warp and the thread of the pattern always go crosswise (towards each other).

Before you start weaving your bauble, you need to roughly determine the length of the future product, choose those colors that you like best and arrange them in the required order. It should be remembered that knitting knots significantly shortens the leading thread, which means that you need to take threads 60–80 centimeters long.

Learning to weave baubles is not difficult, the main thing is desire and interest, as well as positive emotions invested in your creation.

How to fasten the threads for weaving baubles?

When weaving, the threads twitch, fall apart and slide away, which greatly complicates the work. Therefore, weaving a bauble begins with fixing it.

You can attach a future bauble with anything and anything - even on a hard table surface, even on a soft pillow. It all depends on in what position and under what circumstances you do it.

The easiest and most convenient way is to fix it with tape. To do this, the threads are laid out in the required order and secured with a piece of scotch tape or electrical tape.

All that is needed is to make sure that the thread does not come out from under it and sometimes, for convenience, attach the "grown" tail to the surface while weaving. Thus, you can weave both at the table and fastening the future product to any other solid surface - a board or a book.

The next method assumes the presence of a regular safety pin. Each thread, taking into account the ponytail for the tie, is tied in the right order, and the pin itself is attached to the fabric of the pillow, tablecloth, carpet or clothing. However, there is a significant disadvantage - the beginning of the bauble does not always turn out smooth, sometimes you have to straighten it yourself.

You can immediately make a loop fastener on the bauble - the required number of threads is folded in half, the leading one is tied to the place where the loop begins, then the warp threads are braided once as many times as is required for the required size of the future loop.

As soon as it seems enough for you, you can start weaving itself. The method is convenient for starting direct weaving, which was already discussed earlier.

You can also use stationery clips, clothespins, clasps from hardware stores, paper clips or clipboards.

In general, there are many ways to start a bauble. It all depends on the imagination and the means at hand.

Often, baubles are woven on the road, in cars, in field conditions. All of the above methods are good for securing threads in all conditions.

Learn about weaving baubles from threads from the proposed video.

Knots for weaving baubles from threads

In order to start weaving beautiful thread baubles, you need to remember the four main knots and their designations in the diagrams.

There are only two simple (looped) knots - right and left loop knots.

To make the first of them, it is necessary that the working thread is to the right of the knotted thread. Rows of such nodes go from right to left.

The working thread for the left buttonhole should be in the opposite position. The rows run from left to right.

These knots, most often, are tied in pairs.

There are the following types of nodes:

• straight (left-left);
• reverse (right-right);
• left tatting (left-right;
• right tatting (right-left).

The implementation of these knots can be learned by carefully studying the weaving patterns.

At first, it seems difficult to grasp all the nuances of such a simple matter as fenkweaving, but soon after starting work, the fingers will automatically begin to tighten the knots, and shift the threads to the right sides.

Patterns for weaving baubles from threads

Like patterns for knitting or embroidery, all these knots in various combinations can be found in special patterns. For those who are just starting to weave and are not sure that they will be able to create their own unique masterpiece the first time, there are special patterns for weaving baubles from threads, in which everything that was described in the paragraph above is described in detail and clearly.

It is always easy to find them on the Internet or books on needlework - from simple ones in a few threads to more complex and voluminous ones, in 20-30 or even 40 threads.

Some, the most simple baubles, are woven without schemes at all. However, in order to weave an original, beautiful bracelet, it is still worth learning how to disassemble the circuits. Reading them is not so difficult - you just have to remember the special designations of the four types of nodes and determine what the scheme is - with a full or incomplete cycle.

The cycle is determined by the arrangement of the threads. If the diagram shows the correct arrangement of threads and the sequence of colors on both sides of the product, then the cycle is complete.

If the threads from the end and the beginning do not match, then the cycle is incomplete.

Schemes also come with an even and odd number of threads in bundles. This means that one color will be more than another.

At first, it is quite difficult to figure out what is what, but constant work on the schemes develops movements to automatism.

How to decorate thread baubles?

Fenichka itself is an original and beautiful piece of jewelry that suits almost everyone and everything (with rare, rare exceptions). However, something can still be added to it, making an ordinary bracelet made of threads unique.

Handicraft stores now sell a variety of fun, cute and beautiful jewelry that you can always add to your bauble.

For example, a thin bracelet can be complemented by sewing a small chain or a strip of rhinestones to it. And by choosing cute beads, sequins and beads, the bracelet can be made in any style - from classic to punk.

Bracelets made from natural threads (such as wool or cotton) can be supplemented wooden beads or other "natural" materials.

You can decorate your Indian-style thread by sewing some bird feathers and beads onto the bracelet. Those who know how to embroider can embroider a name or an ornament on top of the wickerwork, making a personalized bauble.

Such decorations, complemented by beautiful details, can be a great gift for a holiday or memorable occasion. Besides, beautiful baubles are suitable for both adults and children, boys and girls.

In contact with

Fenichki (fennecs, or, as they are also called, friendship bracelets) are jewelry, the name of which speaks for itself. Usually one of the friends weaves such an ornament for another, and the other wears it until the thread breaks or frays. They are usually made of threads, but there are other varieties, for example, from beads, ribbons, laces.

At one time, this tradition was popular with American hippies, who, after exchanging baubles, were considered named brothers. Well, today fennecs are used simply as decoration, although if you want to say something with this gift, this can also be done: after all, each of the flowers or their combinations used in such decoration has its own symbolism, which we will talk about a little further.

For now, let's consider what baubles are and what they are made of.

From beads - perhaps, this is the most difficult type of baubles to manufacture, because it requires perseverance, the ability to choose colors correctly, and great patience. Moreover, beads, unlike threads, do not lie in a calm heap, but are constantly crumbling ... But the decoration that is obtained as a result is no worse than the works of art that were made by, say, embroiderers with beads in the 19th century.

Thread baubles - most often they are woven from iris and floss, however, options are possible, for example, acrylic or wool. You can create different types of patterns using a variety of nodes. Most often they talk about baubles with oblique weaving or straight weaving.

Baubles from ribbons are made easier and faster than their "brothers" from other materials. Most often they take satin ribbons of one color or two, combined with each other.

There are other options such as baubles made of leather or imitation leather, hemp (material that is made from the hemp stem), colored synthetic laces... In general, such ornaments are woven from everything from which you can weave something, there is no limit to imagination 🙂

Today we will talk in more detail about, perhaps, the most common baubles - from floss threads.

What are the types of floss and how to choose them?

Any threads, before they are sold to you in a store, go through several mandatory processing stages. First, using a twisting machine, several threads are twisted into one, then these threads go through the process of cooking in an alkaline solution, discoloration and dyeing, at the end they are starch and wound on spools or bobbins.

There is a huge variety of threads for weaving and embroidery, but floss or iris are best suited for making baubles. One thread of floss consists of six thinner threads, each of which, in turn, is made of even thinner fibers: spatula and cotton.

Cotton floss threads are very strong, but they lack natural shine. Therefore, it is given to them through a mercerizing process. The spatula floss threads are less strong, but they have a beautiful natural shine.

In addition to these two types, you can find on sale silky floss made from flax and woolen threads. There are also beautiful types of threads with the addition of metallized threads, as well as processed with a special fluorescent compound that glows in the dark. With all of these different types, you can experiment almost endlessly!

How to weave baubles from floss threads?

To understand how to weave baubles out of floss, we first need to understand how to read bauble patterns - after all, it is on their basis that all masterpieces from threads are created. And for this it is necessary to understand how different types of knots are indicated on the diagrams and how to tie these knots correctly.

Actually, at the heart of the whole process of fennel weaving are two simple, or looped knots - right and left. Right knot - in which the working thread is located to the right of the knotted thread, and in the left, respectively, to the left. Depending on the combination of looped knots that make up a pair (left and left, left and right, right and left, right and right), 4 types of knots are distinguished.

Straight knot

This is a combination of two left loop knots. In the diagrams, it is indicated by an arrow that points to the right and down - in the direction where the working thread goes. The color of the resulting knot will match the color of the working thread.

Reverse knot

This is, accordingly, a combination in one pair of two right loop knots. Its designation is an arrow pointing down and to the left, and the working thread also goes there.

Left tatting

The working thread in it, respectively, is located to the left and to the left leaves. It is a pair of left and right loop knots. Here it is already worthwhile to disassemble step by step how such a knot is woven.

1. To begin with, we tie the left loop knot, while the threads change places, and the working thread goes to the right.
2. Then we make the right loop knot with a working thread. The threads are swapped back, returning to their original position.

Therefore, the designation of the node on the diagram is as follows - an arrow going first to the right, then to the left.

Right tatting

Its designation in the diagrams is an arrow going to the left and then to the right. And it is performed mirrored to the left - first we perform the right loop knot with the right working thread, leading it to the left, and then the left one, returning it back to its original position.

Knowing these basic knots, you can easily read bauble patterns, which means you can practice complex patterns.

How to fasten the threads for weaving baubles?

In order for the pattern to turn out even, and the threads do not fall apart, they must be fixed at the beginning of work. You can do this in one of the following four ways.

Method number 1: we tie each thread with a knot to a pin, and fasten the pin itself to the fabric, for example, a tablecloth, the back of a sofa or even jeans on the knee 🙂 A very convenient option when you weave a bauble in hiking conditions.

Method number 2: the thread can be fixed using a tablet - this is a special board with a paper clip, which can be used to press the threads, it is sold in stationery stores.

Method number 3: put the threads on the cover of a thick notebook or book and press it with a crocodile clip.

Method number 4: using tape or adhesive plaster, fix the threads at the edge of some fixed surface, for example, a table top.

In any of the ways, the main thing is to distribute the threads in advance in the order in which they should go on the diagram.

How to determine the length of the bauble thread?

Of course, when you gain experience, you can easily determine the required length of threads for a particular pattern by eye. But if you are just starting to get acquainted with the fascinating world of fenk weaving, then you should know that when weaving, a lot of threads go into knots, and the finished fennec turns out to be several times shorter than the original thread. Only one double knot takes up about 8 millimeters of thread. Moreover, on both sides, 5-8 centimeters must be left to make ties.

If the fennec of your choice is woven with oblique weaving, and the pattern is simple (this is a symmetrical pattern, not a complex pattern), the pattern is based on 1-2 knots and no more than 8 threads, you can take threads 80 centimeters long. If the scheme is more complicated, then the length should be taken about 1 meter. No more needed - the longer they are, the more they will become entangled and the more difficult it will be to untangle them, especially if you are braiding a bauble somewhere outside your home, for example, in transport or while waiting in line.

If the thread runs out earlier, you can always bring it to the wrong side, and add a new one in its place. However, if you do not want such difficulties, then the length can be measured and more than 1 meter, only each thread will need to be wound in a separate hank and secured with something, for example, a clerical elastic band.

On one of the sites on the Internet, a formula was discovered by which you can calculate the length of the thread:

Length \u003d wrist circumference x 4.3 + tie length x 2

For reliability, you can add about 10 centimeters to the resulting figure.

Straight weaving is usually more difficult, because these are more complex knots and patterns. Therefore, if you immediately take on it, then be prepared for the fact that you will have to lengthen the threads (in one of our articles we already wrote about how to add a thread, so we will not repeat it now). Most often, the length is determined by how many knots will be woven with this particular thread. For example, the thread of the background (leading) should be made the longest, and the extreme ones, as a rule, are the shortest, and their length can be calculated by adding the supposed length of the fennec and the strings.

You can determine the length of the bauble using the formula: number of rows x 2.3.We take the length of the remaining threads at the rate of 0.8 mm (and preferably 1 cm) for each knot in the scheme.

However, if you do not want all these mathematical difficulties, then it is better to just take 1 meter of threads, master their lengthening to perfection so that there are no unnecessary knots, and add the required length whenever necessary.

Symbolism of flowers in weaving of floss baubles

When choosing colors for your future work, do not forget that each of them, both individually and in combination, has its own meaning.

So, red symbolizes love, fire, energy, passion, affection, joy.

Orange - also energy, affection, fire, and besides, sexuality and pacifism.

Yellow - abundance (after all, this is the color of money, gold), summer and sun, as well as envy, jealousy, insincerity. But this is also a symbol of faith, fate, beauty, longing.

Green - life, hope, harmony, nature; youth, faith, eternity.

Blue - the color of the sky and water - symbolizes tranquility and infinity, mind and peace, friendship, hope and harmony.

Blue - it is also peace and tranquility, harmony, as well as purity, infinity, openness to new things, long memory, spirit, love for God, friendliness.

Violet - friendship, originality, as well as wisdom, mysticism, dreams.

White Is the Chinese Yang energy. This color is a symbol of sophistication, innocence, truth, independence, purity, beginning, path, faith, light, freedom, life, goodness.

The black - its opposite is Yin energy, independence, loneliness, sadness, strong energy, closeness to communication, magic, fearlessness, detachment, purification.

Gray - sadness, modesty, old age, insensitivity, punctuality.

Color combinations in weaving floss baubles:

Two colors each:

Green and red - love for nature.

Red and yellow - crazy Love.

Red and blue - pacifism.

White and red - free love.

Black and red - unhappy love, anarchy.

Yellow and green - Greenpeace.

Blue and yellow - the sky and the sun.

Purple and yellow - insanity, madness, paranoia.

Black and yellow - evil, black magic.

Green and white - belief in God, white magic.

Blue and white - inner light, harmony in detachment from the world.

White and blue - hope.

White and pink - variability.

Purple and black - black magic.

Black and white - pride, loneliness, the cycle of birth and death, Yin and Yang.

Three colors each:

White, orange and green - hippies.

White, red and black symbolize the path of life (birth, life and death).

Blue, white and black - hope.

Green, blue and yellow - nature, pacifism, naturalness, brotherhood, harmony.

Yellow, green and red - reggae music, Rastafarianism.

Yellow, blue and orange - passion for esotericism, culture of the East.

Orange, green and white - passion for the culture of Ireland, Celts, Druids.

Black, brown and yellow - black magic.

Black, red and white - the symbolism of anarchy.

And finally, a color matching table that will help you determine which colors should be used together, and which ones are categorically contraindicated.

Fenichki are bracelets woven from different materials: laces, leather strips or floss threads. Such products have become symbols of strong friendship. For the first time, hippies began to give them to each other, however, the decoration itself has deeper roots, it is part of the culture of the Indians of North America.

Today, such needlework, along with embroidery, is popular all over the world. Schemes of how to weave baubles from floss threads are known to people of different ages. The secret of the popularity of such products is in the simplicity of execution: the leading thread is thrown onto the next one on the right, passed under it and the knot is tightened at the base.

2-thread baubles

This method of creating thread baubles for beginners works best. To do this, take two strings of the required length. On the one hand, they are tied into a knot. You need to make a bracelet together. The essence of the work is that the fibers need to be pulled a little and twisted in different directions.

One thread is held by one person and twists it clockwise, the other is held by a second person and twists it, respectively, in the opposite direction. Then both are folded together, stretched to length, released so that the fibers are intertwined with each other. The free ends are connected with a knot - the bracelet is ready.

3-thread baubles

You need to take three with a length of at least 60 cm. Then put them together, align, fold in half. At the fold, make a loop of such a size that the index finger passes into it, tie a knot. Now the workpiece must be attached to any convenient surface with tape, you can use a clip or a pin. All knots are made with a leading thread - the one that is located on the left before weaving a row.

Weaving runs from left to right:

1. Put the leading thread on the next one on the right, thread it under it, make a knot.
2. The resulting knot must be transferred to the base, and then another one must be made. That is, there will be two knots for each thread.
3. Further, in the same way, all subsequent ones in order are wrapped with a leading thread.

When the first row is over, you can move on to the second. It is done in the same way, another thread becomes the leading one, which turned out to be the extreme left. The braiding is brought to the required size so that the bracelet fits well on the wrist, its final part is fixed. For this type of weaving, you can pick up interesting patterns.

4-thread baubles

The principle of operation is similar to the previous one, only an extra element is added. Four fibers of different colors must be evenly folded together, on one side make a knot for fixing. The resulting straight ribbon must be attached with tape to a hard surface (table or folder). The threads are neatly distributed by color in a strictly defined sequence, for example, green, yellow, red, blue.

1. Put the green thread on top of the yellow one, and thread the end under it, make a knot.
2. Repeat this action, since there should be two knots for each thread.
3. Now green has become extreme again, it needs to be linked to red twice.
4. Further, such actions are repeated with blue (green also remains extreme).

When the first row is finished, the green one will be the last. The second row of braids will start with yellow. And so in each row, the threads will alternate, forming a multi-colored pattern. As soon as the bracelet is of the desired length, all four strings are folded back together and tied in a knot, as at the very beginning.

6-thread baubles

The ends of the six fibers are knotted, secured. The left thread (1st) is placed on the 2nd and threaded under the 3rd. Now the right extreme (6th) is threaded under the 5th and pulled over the 4th and under the 1st.

Weave in this way to the desired length of the product. After that, the free ends are tied with a simple knot, and the excess is neatly cut off.

8-thread baubles

For weaving, you need to select fibers of four different colors (2 each). They are laid out by 4 in a mirror image. Now you need to tie them with a knot on one side, securely fasten with a piece of tape. Half of all fibers are braided with the left leading thread. This means that the other three are sequentially braided with this thread, on each of which two knots are made.

Now the rightmost thread is taken and, moving to the left, the next half of the fibers is braided. After that, the two leading lines are connected by two knots. The first row in the form of a corner is ready. The second is also woven, but now the second thread from the right and left is chosen as the leaders. Fenichka is brought to the desired length, as a result, a beautiful flat multi-colored arrow is obtained. Colors can be selected contrasting or make smooth transitions of tones.

Weaving baubles is an exciting activity for novice craftsmen, which is interesting for both adults and children. This self-made bracelet will be a great gift for friends and relatives. So you can express your affection for them, give them a piece of your positive energy.

Making a solar USB charger for your phone with your own hands is one of the most interesting and useful projects on. Making a homemade charger is not too difficult - the necessary components are not very expensive and are easy to obtain. Solar USB chargers are ideal for charging small devices like your phone.

The weak point of all homemade solar chargers is the batteries. Most are assembled on the basis of standard NiMH batteries - cheap, affordable and safe to use. But unfortunately, NiMH batteries have too low voltage and capacity to be seriously considered as a quality, the power consumption of which only grows every year.

For example, the iPhone 4's 2000 mAh battery can still be fully recharged from a homemade solar charger with two or four AA batteries, but the iPad 2 has a 6000 mAh battery, which is no longer so easy to recharge with this charger.

The solution to this problem is to replace nickel-metal hydride batteries with lithium ones.

This guide will show you how to make a solar USB charger with a lithium battery with your own hands. First, compared to this homemade charger, it will cost you a lot. Secondly, it is very easy to assemble it. And most importantly, this lithium USB charger is safe to use.

Step 1: Required components for solar USB charging assembly.

Electronic components:

• Solar cell 5V or higher
• 3.7V Li-ion battery
• Li-ion battery charging controller
• DC USB boost circuit
• 2.5mm Panel Mount Connector
• 2.5mm plug with wire
• Diode 1N4001
• The wire

Construction materials:

• Insulating tape
• Heat shrink tubing
• Double Sided Foam Tape
• Solder
• Tin box (or other enclosure)

Instruments:

• Soldering iron
• Hot glue gun
• Drill
• Dremel (optional, but desirable)
• Nippers
• Wire stripper
• Friend's help

This guide will show you how to make a solar phone charger. You can refuse to use solar panels and limit yourself only to the manufacture of a regular USB charger on lithium-ion batteries.

Most of the components for this project can be purchased from online electronics stores, but the USB DC boost circuit and lithium-ion battery charge controller will not be easy to find. Later in this guide, I'll show you where you can get most of the necessary components and what each one is for. Based on this, you yourself decide which option suits you best.

Step 2: Benefits of Lithium Battery Chargers.

You may not guess, but most likely the lithium-ion battery is right now in your pocket or on your desk, or maybe in your wallet or. Most modern electronic devices use lithium-ion batteries, which are characterized by high capacity and voltage. They can be recharged many times. Most AA batteries chemical composition are nickel-metal hydride and cannot boast of high technical characteristics.

From a chemical point of view, the difference between a standard AA NiMH battery and a lithium ion battery lies in the chemical elements contained within the battery. If you look at Mendeleev's periodic table of elements, you will see that lithium is in the left corner next to the most reactive elements. Nickel, however, is located in the middle of the table next to chemically inactive elements. Lithium is so highly reactive due to the fact that it only has one valence electron.

And it is precisely for this reason that there are many complaints about lithium - sometimes it can get out of control due to its high chemical activity. A few years ago, Sony, a leader in laptop battery production, manufactured a batch of low-quality laptop batteries, some of which spontaneously burned.

That is why, when working with lithium-ion batteries, we must adhere to certain precautions - very accurately maintain the voltage during charging. This manual uses 3.7 V batteries, which require a charging voltage of 4.2 V. If this voltage is exceeded or decreased, the chemical reaction can get out of control with all the ensuing consequences.

This is why extreme care must be taken when working with lithium batteries. If handled with care, they are reasonably safe. But if you do inappropriate things with them, it can lead to big trouble. Therefore, they should only be operated strictly according to the instructions.

Step 3: Selecting a lithium-ion battery charge controller.

Due to the high chemical reactivity of lithium batteries, you must be 100% sure that the charge voltage control circuit will not let you down.

Although you can make your own voltage control circuit, it's best to just buy a ready-made circuit that you can be sure of working. Several charge control schemes are available to choose from.

Adafruit is currently launching the second generation of lithium battery charge controllers with several available input voltages. These are pretty good controllers, but they are too big. It is unlikely that on their basis it will be possible to assemble a compact charger.

You can buy small lithium battery charging controller modules on the Internet, which are used in this manual. I have collected many others based on these controllers. I like them for their compactness, simplicity and the presence of an LED indication of the battery charge. As with the Adafruit, the lithium battery can be charged via the controller's USB port when the sun is out. USB charging is an extremely useful option for any solar charger.

Regardless of which controller you choose, you must know how it works and how to properly operate it.

Step 4: USB port.

Most modern devices can be charged via the USB port. This is the standard all over the world. Why not just plug the USB port directly into the battery? Why do you need a dedicated USB charging circuit?

The problem is that according to the USB standard, the voltage is 5V, and the lithium-ion batteries that we will be using in this project are only 3.7V. Therefore, we will have to use a USB DC boost circuit that increases the voltage to sufficient to charge various devices. On the contrary, most commercial and home-made USB chargers use step-down circuits, since they are assembled on the basis of 6 and 9 V batteries. Lower-voltage circuits are more complex, so it is better not to use them in solar chargers.

The circuit used in this manual was selected after extensive testing of various options. It is almost identical to the Minityboost Adafruit scheme, but costs less.

Of course you can buy an inexpensive USB charger online and disassemble it, but we need a circuit that converts 3V (voltage of two AA batteries) to 5V (voltage on USB). Disassembling a regular or car USB charger will do nothing, since their circuits work to lower the voltage, but on the contrary, we need to increase the voltage.

In addition, it should be noted that the Mintyboost scheme and the scheme used in the project are capable of working with Apple gadgets, unlike most others. uSB chargers devices. Apple devices check USB info pins to know where they are connected. If the Apple gadget determines that the info pins are not working, it will refuse to charge. Most other gadgets do not have this check. Trust me - I have tried many cheap charging schemes from eBay - none of them have been able to charge my iPhone. You don't want your homemade USB charger to be unable to charge Apple gadgets.

Step 5: Battery selection.

If you google a little, you'll find a huge variety of sizes, capacities, voltages and costs. At first, it will be easy to get confused in all this diversity.

For our charger we will be using a 3.7V Lithium Polymer (Li-Po) battery, which is very similar to an iPod or mobile phone battery. Indeed, we need a battery exclusively for 3.7 V, since the charging circuit is designed specifically for this voltage.

The fact that the battery should be equipped with built-in overcharge and over-discharge protection is not even discussed. This protection is commonly referred to as "PCB protection". Search for these keywords on the eBay online auction site. From itself it is just a small printed circuit board with a chip that protects the battery from overcharging and discharging.

When choosing a lithium-ion battery, look not only at its capacity, but also at its physical size, which mainly depends on the case you choose. I had an Altoids tin box as a case, so I was limited in the choice of the battery. At first I thought to buy a 4400 mAh battery, but due to its large size I had to limit myself to a 2000 mAh battery.

Step 6: Connect the solar panel.

If you are not going to make a solar charger, you can skip this step.

This guide uses a 5.5V 320mA solar cell in a hard plastic case. Any large solar panel will do. For the charger, it is best to choose a battery rated for 5-6 V.

Take the end of the wire, split it in two and strip the ends a little. The wire with the white stripe is negative, and the completely black wire is positive.

Solder the wires to the corresponding pins on the back of the solar panel.

Cover the solder joints with tape or hot glue. This will protect them and help reduce stress on the wires.

Step 7: Drill a tin box or case.

Since I used an Altoids tin box for the case, I had to do a bit of work with a drill. In addition to a drill, we also need such a tool as a dremel.

Before you start working with the tin box, fold all the components into it to make sure in practice that it suits you. Think about how best to place the components in it, and only then drill. The locations of the components can be marked with a marker.

After marking the places, you can get to work.

There are several ways to bring out the USB port: make a small cut right at the top of the box, or drill a hole of the appropriate size on the side of the box. I decided to make a hole in the side.

First, attach the USB port to the box and mark its location. Drill two or more holes within the designated area.

Grind the hole with a dremel. Be sure to follow safety precautions so as not to injure your fingers. Under no circumstances hold the box in your hands - hold it in a vice.

Drill a 2.5mm hole for the USB port. Expand it with a dremel if necessary. If you don't plan on installing a solar panel, then there is no need for a 2.5mm hole!

Step 8: Connect the charging controller.

One of the reasons I chose this compact charging controller is its high reliability. It has four contact pads: two in front next to the mini-USB port, where DC voltage is supplied (in our case, from solar panels), and two in the back for the battery.

To connect the 2.5 mm connector to the charging controller, you need to solder two wires and a diode from the connector to the controller. In addition, it is advisable to use heat shrink tubing.

Fix the 1N4001 diode, charging controller and 2.5mm connector. Place the connector in front of you. Looking at it from left to right, the left contact will be negative, the middle positive, and the right one is not used at all.

Solder one end of the wiring to the negative leg of the connector, and the other to the negative terminal on the board. In addition, it is advisable to use heat shrink tubing.

Solder one more wire to the diode leg, next to which the mark is applied. Solder it as close to the base of the diode as possible to save more space. Solder the other side of the diode (unmarked) to the middle leg of the connector. Again, try to solder as close to the base of the diode as possible. Finally, solder the wires to the positive terminal on the board. In addition, it is advisable to use heat shrink tubing.

Step 9: Connect the battery and USB circuit.

At this stage, you only need to solder four additional contacts.

You need to connect the battery and USB circuit to the charge controller board.

Cut some wires first. Solder them to the positive and negative pins on the USB circuit, which are located on the underside of the board.

Then, connect these wires together with the wires coming from the lithium-ion battery. Make sure you connect the negative wires together and connect the positive wires together. Let me remind you that the red wires are positive, and the black ones are negative.

After twisting the wires together, weld them to the contacts on the battery, which are on the back of the charge controller board. It is advisable to thread through the holes before soldering the wiring.

Now we can congratulate you - you have 100% completed the electrical part of this project and you can relax a little.

At this stage, it is a good idea to test that the circuit works. Since all the electrical components are connected, everything should work. Try charging your iPod or any other gadget with a USB port. The device will not charge if the battery is low or defective. Also, place the charger in the sun and see if the battery is charging from the solar panel - the little red LED on the charge controller board should light up. You can also charge the battery via a mini-USB cable.

Step 10: Electrical isolation of all components.

Before placing all the electronic components in the tin box, we must be sure that it cannot cause a short circuit. If you have a plastic or wooden case, then skip this step.

Place a few strips of electrical tape on the bottom and sides of the tin box. It is in these places that the USB circuit and charging controller will be located. The photos show that the charging controller was left loose.

Try to insulate everything thoroughly so that a short circuit does not occur. Make sure that the solder is strong before applying hot glue or tape.

Step 11: Place the electronic components in the housing.

Since the 2.5mm connector needs to be bolted in place, place it first.

There was a switch on the side of my USB circuit. If you have the same circuit, then first check if the switch that is needed to turn on and off the "charging mode" works.

Finally, you need to secure the battery. For this purpose, it is better to use not hot glue, but several pieces of double-sided tape or electrical tape.

Step 12: Operate your homemade solar charger.

In conclusion, let's talk about the correct operation of a homemade USB charger.

The battery can be charged via the mini-USB port or from the sun. A red LED on the charge controller board indicates charging, and a blue LED indicates a fully charged battery.