DIY solar battery. Homemade solar battery DIY solar panels made from LEDs

Independent production of any technical device from improvised means is always associated with several factors. On the one hand, tangible financial savings, on the other, a significant investment of time and labor. In addition, it is quite possible that the assembled product will work somewhat differently than expected and produce completely different parameters. Solar batteries made from diodes are no exception.

It is quite possible to assemble such a battery, but this will require, firstly, diodes in sufficiently large quantities, secondly, a board for the substrate, and thirdly, soldering equipment and skills in working with it. And, naturally, a reserve of time, since placing and soldering the required number of diodes is a rather long process.

How is photocurrent obtained?

The diode contains a semiconductor crystal inside. Accordingly, under the influence of sunlight in the p-n-zone region, electrons begin to move and form a directed flow. He is also a photocurrent. Therefore, a regular diode can be used as a solar battery element.

Another thing is that the voltage generated by such a diode is very small (for diodes of the KD type it is about 0.5 V), and the current strength is no more than 7 mA. For comparison, the current consumption of a white LED reaches 20 mA.

From old diodes

The first stage of making a diode battery with your own hands is opening the internal crystal so that the rays of the sun fall on it. To do this, the upper part of the diode is carefully cut off and removed, and the lower part, with the crystal, is heated over a gas stove that is turned on for about 20 seconds.

This is necessary so that the solder holding the crystal melts, and the crystal can be easily removed using tweezers. The resulting crystals are soldered to the circuit board (any suitable substrate can be used).

The number of crystals and their arrangement depend on the ultimately required parameters. For example, to obtain an output of 2-4 V, you can assemble 5 blocks of 4-5 crystals soldered in series. The blocks are switched among themselves in parallel. This method allows you to obtain the desired voltage with a current sufficient to power a small LED device. If you use only a parallel connection, then with increased voltage the resulting current will be too small.

From LEDs

Modern LEDs are also suitable for making a mini solar battery. The principle of their operation is actually similar to conventional diodes, the only difference being the presence of a special plastic housing. This body acts as a kind of lens and focuses the sun's rays on a conductive crystal.

The generated voltage due to this will be higher than that of conventional diodes. So, for a red-transparent LED it is approximately 1.3 V, for an infrared LED - 0.9 V, for a green LED - 1.5 V. As for the current generated by the battery, its value will be insignificant. As a rule, it is possible to obtain about 0.5 mA from a battery of 100 diodes.

LEDs can be placed either on a textolite (or similar) substrate or on plain thick cardboard. The principles of constructing a circuit and calculating the required parameters are the same as when working with conventional diodes.

Is there any benefit?

When it comes to LEDs, do not forget about the phenomenon of current consumption by the diodes themselves and their spontaneous glow. In other words, while some LEDs generate electricity, the rest will consume it. As a result, the circuit voltage increases far out of proportion to the number of elements involved, and at a certain point the “return losses” become too significant.

In addition, a homemade diode battery can only work normally in clear sunny weather. In cloudy conditions, its production tends to zero.

Originally published at Professionally about energy. Please leave any comments there.

A radio designer's household will always contain old diodes and transistors from radios and televisions that have become unnecessary.

In skillful hands, this is wealth that can be put to good use. For example, make a semiconductor solar battery to power a transistor radio in field conditions. As you know, when illuminated with light, a semiconductor becomes a source of electric current - a photocell.

We will use this property. The current strength and electromotive force of such a photocell depend on the material of the semiconductor, the size of its surface and illumination. But in order to turn a diode or transistor into a photocell, you need to get to the semiconductor crystal, or, more precisely, you need to open it.

We’ll tell you how to do this a little later, but for now, take a look at the table that shows the parameters of homemade photocells. All values were obtained under illumination with a 60 W lamp at a distance of 170 mm, which approximately corresponds to the intensity of sunlight on a fine autumn day.

As can be seen from the table, the energy generated by one photocell is very small, so they are combined into batteries. To increase the current supplied to the external circuit, identical photocells are connected in series. But the best results can be achieved with a mixed connection, when the photobattery is assembled from series-connected groups, each of which is made up of identical parallel-connected elements (Fig.

3). Pre-prepared groups of diodes are assembled on a plate made of getinax, organic glass or textolite, for example, as shown in Figure 4. The elements are connected to each other by thin tinned copper wires.

It is better not to solder the terminals suitable for the crystal, as this can damage the semiconductor crystal due to high temperature. Place the plate with the photocell in a durable case with a transparent top cover.

Solder both pins to the connector - you will connect the cord from the radio to it. A solar photobattery of 20 KD202 diodes (five groups of four parallel-connected photocells) in the sun generates a voltage of up to 2.1 V at a current of up to 0.8 mA. This is quite enough to power a radio receiver using one or two transistors.

Now let's talk about how to turn diodes and transistors into photovoltaic cells. Prepare a vice, side cutters, pliers, a sharp knife, a small hammer, a soldering iron, POS-60 tin-lead solder, rosin, tweezers, a 50-300 µA tester or microammeter and a 4.5 V battery. Diodes D7, D226, D237 and others in similar cases should be disassembled this way.

First, cut off the leads along lines A and B with side cutters (Fig. 1). Gently straighten the crumpled tube B to release terminal D. Then clamp the diode in a vice by the flange.

Apply a sharp knife to the weld seam and, lightly hitting the back of the knife, remove the cover. Make sure that the knife blade does not go deep inside - otherwise you can damage the crystal.

Conclusion D: Remove paint - the photocell is ready. For diodes KD202 (as well as D214, D215, D242-D247), use pliers to bite off flange A (Fig. 2) and cut off terminal B. As in the previous case, straighten the crumpled tube B, free the flexible terminal G.

Hello dear readers of the prosamostroi.ru blog! In our 21st century, changes are constantly taking place. They are especially noticeable in the technological aspect. Cheaper energy sources are being invented, and various devices are being distributed everywhere to make people’s lives easier.

Today we will talk about such a thing as a solar battery - a device that is not breakthrough, but nevertheless, which is becoming more and more part of people’s lives every year. We will talk about what this device is, what advantages and disadvantages it has. We will also pay attention to how to assemble a solar battery with your own hands.

Solar battery: what is it and how does it work?

A solar battery is a device that consists of a certain set of solar cells (photocells) that convert solar energy into electricity. Most solar panels are made of silicon since this material has good efficiency in “processing” incoming sunlight.

Solar panels work as follows:

Photovoltaic silicon cells, which are packaged in a common frame (frame), receive sunlight. They heat up and partially absorb the incoming energy. This energy immediately releases electrons inside the silicon, which through specialized channels enter a special capacitor, in which electricity is accumulated and, being processed from constant to variable, is supplied to devices in the apartment/residential building.

Advantages and disadvantages of this type of energy

The advantages include the following:

Our Sun is an environmentally friendly source of energy that does not contribute to environmental pollution. Solar panels do not release various harmful waste into the environment.

Solar energy is inexhaustible (of course, while the Sun is alive, but this is still billions of years in the future). From this it follows that solar energy would definitely be enough for your entire life.

Once you have installed solar panels correctly, you will not need to maintain them frequently in the future. All you need is to carry out a preventive examination once or twice a year.

Impressive service life of solar panels. This period starts from 25 years. It is also worth noting that even after this time they will not lose their performance characteristics.

Installation of solar panels may be subsidized by the government. For example, this is actively happening in Australia, France, and Israel. In France, 60% of the cost of solar panels is returned.

The disadvantages include the following:

So far, solar panels are not competitive, for example, if you need to generate large amounts of electricity. This is more successful in the oil and nuclear industries.

Electricity production directly depends on weather conditions. Naturally, when it’s sunny outside, your solar panels will operate at 100% power. When it’s a cloudy day, this figure will drop significantly.

To produce a large amount of energy, solar panels require a large area.

As you can see, this energy source still has more advantages than disadvantages, and the disadvantages are not as terrible as it would seem.

Do-it-yourself solar battery from improvised means and materials at home

Despite the fact that we live in a modern and rapidly developing world, the purchase and installation of solar panels remains the lot of wealthy people.

The cost of one panel that will produce only 100 Watts varies from 6 to 8 thousand rubles. This is not counting the fact that you will have to buy capacitors, batteries, a charge controller, a network inverter, a converter and other things separately. But if you don’t have a lot of money, but want to switch to an environmentally friendly source of energy, then we have good news for you - you can assemble a solar battery at home.

And if you follow all the recommendations, its efficiency will be no worse than that of the version assembled on an industrial scale. In this part we will look at step-by-step assembly. We will also pay attention to the materials from which solar panels can be assembled.

From diodes

This is one of the most budget materials.

If you are planning to make a solar battery for your home from diodes, then remember that these components are used to assemble only small solar panels that can power some minor gadgets. D223B diodes are best suited. These are Soviet-style diodes, which are good because they have a glass case, due to their size they have a high installation density and have a reasonable price.

After purchasing the diodes, clean them of paint - to do this, just place them in acetone for a couple of hours. After this time, it can be easily removed from them.

Then we will prepare the surface for future placement of diodes. This can be a wooden plank or any other surface. It is necessary to make holes in it throughout its entire area. Between the holes it will be necessary to maintain a distance of 2 to 4 mm.

Then we take our diodes and insert them with aluminum tails into these holes. After this, the tails need to be bent in relation to each other and soldered so that when receiving solar energy they distribute electricity into one “system”.

Our primitive solar battery made of glass diodes is ready. At the output, it can provide energy of a couple of volts, which is a good indicator for a homemade assembly.

From transistors

This option will be more serious than the diode one, but it is still an example of harsh manual assembly.

In order to make a solar battery from transistors, you will first need the transistors themselves. Fortunately, they can be bought in almost any market or electronic stores.

After purchase, you will need to cut off the cover of the transistor. Under the cover is hidden the most important and necessary element - a semiconductor crystal.

You can use both wood and plastic. Plastic, of course, will be better. We drill holes in it for the transistor leads.

Then we insert them into the frame and solder them together, observing the “input-output” standards.

At the output, such a battery can provide enough power to operate, for example, a calculator or a small diode light bulb. Again, such a solar battery is assembled purely for fun and does not represent a serious “power supply” element.

From aluminum cans

This option is already more serious, unlike the first two.

This is also an incredibly cheap and effective way to get energy. The only thing is that at the output there will be much more of it than in the versions of diodes and transistors, and it will not be electrical, but thermal. All you need is a large number of aluminum cans and a housing.

A wooden body works well. The front part of the housing must be covered with plexiglass. Without it, the battery will not work effectively.

Before starting assembly, you need to paint the aluminum cans with black paint. This will allow them to attract sunlight well.

Then, using tools, three holes are punched in the bottom of each jar. At the top, in turn, a star-shaped cutout is made. The free ends are bent outwards, which is necessary for improved turbulence of the heated air to occur.

After these manipulations, the cans are folded into longitudinal lines (pipes) into the body of our battery.

A layer of insulation (mineral wool) is then placed between the pipes and the walls/back wall. The collector is then covered with transparent cellular polycarbonate.

This completes the assembly process. The last step is to install the air fan as a motor for the energy carrier. Although such a battery does not generate electricity, it can effectively warm up a living space.

Of course, this will not be a full-fledged radiator, but such a battery can warm up a small room - for example, an excellent option for a summer house. We talked about full-fledged bimetallic heating radiators in the article - which bimetallic heating radiators are better and stronger, in which we examined in detail the structure of such heating batteries, their technical characteristics and compared manufacturers. I advise you to read it.

Do-it-yourself solar battery - how to make, assemble and manufacture?

Moving away from homemade options, we will pay attention to more serious things.

Now we’ll talk about how to properly assemble and make a real solar battery with your own hands. Yes - this is also possible. And I want to assure you that it will be no worse than purchased analogues.

To begin with, it is worth saying that you probably will not be able to find on the open market the actual silicon panels that are used in full-fledged solar cells. Yes, and they will be expensive.

We will assemble our solar battery from monocrystalline panels - a cheaper option, but showing excellent performance in terms of generating electrical energy. Moreover, monocrystalline panels are easy to find and are quite inexpensive. They come in different sizes.

The most popular and popular option is 3x6 inches, which produces 0.5V equivalent. We will have enough of these. Depending on your finances, you can buy at least 100-200 of them, but today we will put together an option that is enough to power small batteries, light bulbs and other small electronic elements.

Selection of photocells

As we stated above, we chose a monocrystalline base. You can find it anywhere. The most popular place where it is sold in huge quantities is the Amazon or Ebay trading platforms.

The main thing to remember is that it is very easy to run into unscrupulous sellers there, so buy only from those people who have a fairly high rating. If the seller has a good rating, then you will be sure that your panels will reach you well packaged, not broken, and in the quantity you ordered.

Site selection (attitude system), design and materials

After you have received your package with the main solar cells, you must carefully choose the location for installing your solar panel.

After all, you will need it to work at 100% power, right? Professionals in this matter advise installing it in a place where the solar battery will be directed just below the celestial zenith and look towards West-East. This will allow you to “catch” sunlight almost all day.

Making a solar battery frame

First you need to make a solar panel base.

It can be wooden, plastic or aluminum. Wood and plastic perform best. It should be large enough to fit all your solar cells in a row, but they won't have to hang around inside the entire structure.

After you have assembled the base of the solar battery, you will need to drill many holes on its surface for the future output of conductors into a single system.

By the way, do not forget that the entire base must be covered with plexiglass on top to protect your elements from weather conditions.

Soldering elements and connecting

Once your base is ready, you can place your elements on its surface. Place the photocells along the entire structure with the conductors down (you push them into our drilled holes).

Then they need to be soldered together. There are many schemes on the Internet for soldering photocells. The main thing is to connect them into a kind of unified system so that they can all collect the received energy and direct it to the capacitor.

The last step will be to solder the “output” wire, which will be connected to the capacitor and output the received energy into it.

Installation

This is the final step. Once you are sure that all the elements are assembled correctly, fit tightly and do not wobble, and are well covered with plexiglass, you can begin installation.

In terms of installation, it is better to mount the solar battery on a solid base. A metal frame reinforced with construction screws is perfect. The solar panels will sit firmly on it, not wobble or succumb to any weather conditions.

That's all! What do we end up with? If you made a solar battery consisting of 30-50 photocells, then this will be quite enough to quickly charge your mobile phone or light a small household light bulb, i.e.

What you end up with is a full-fledged homemade charger for charging a phone battery, an outdoor country lamp, or a small garden lantern. If you have made a solar panel, for example, with 100-200 photocells, then we can already talk about “powering” some household appliances, for example, a boiler for heating water. In any case, such a panel will be cheaper than purchased analogues and will save you money.

Video - how to make a solar battery with your own hands?

DIY solar battery in the photo

This section presents photographs of some interesting, but at the same time simple options for homemade solar panels that you can easily assemble with your own hands.

What is better - to buy or make a solar battery?

Let's summarize in this part everything we learned in this article.

Firstly, we figured out how to assemble a solar battery at home. As you can see, a DIY solar battery can be assembled very quickly if you follow the instructions. If you follow the various manuals step by step, you will be able to collect excellent options for providing you with environmentally friendly electricity (or options designed to power small elements).

But still, what is better - to buy or make a solar battery? Naturally, it is better to buy it.

The fact is that those options that are manufactured on an industrial scale are designed to work the way they should work. When manually assembling solar panels, you can often make various mistakes that will lead to them simply not working properly. Naturally, industrial options cost a lot of money, but you get quality and durability.

But if you are confident in your abilities, then with the right approach you will assemble a solar panel that will be no worse than its industrial counterparts.

In any case, the future is here and soon solar panels will be able to afford all the layers. And there, perhaps, there will be a complete transition to the use of solar energy. Good luck!

Below, leave your comments, wishes, ask questions, express your opinion - this is very important to us!

Alternative sources of electricity are gaining popularity every year. Constant increases in electricity tariffs contribute to this trend. One of the reasons that forces people to look for non-traditional power sources is the complete lack of connectivity to public networks.

The most popular alternative power sources on the market are solar panels. These sources use the effect of generating electric current when exposed to solar energy on semiconductor structures made of pure silicon.

The first solar photoplates were too expensive and their use for generating electricity was not profitable. Technologies for the production of silicon solar panels are constantly being improved and now you can purchase a solar power plant for your home at an affordable price.

Light energy is free, and if mini-power plants based on silicon elements are cheap enough, then such alternative power sources will become cost-effective and will become very widespread.

Suitable available materials

Diagram of a solar battery using diodes Many hotheads ask themselves the question: is it possible to make a solar battery from scrap materials. Of course you can! Many people still have a large number of old transistors from the times of the USSR. This is the most suitable material for creating a mini-power station with your own hands.

You can also make a solar cell from silicon diodes. Another material for making solar panels is copper foil. When using foil, a photoelectrochemical reaction is used to produce a potential difference.

Stages of manufacturing a transistor model

Selection of parts

The most suitable for the manufacture of solar cells are powerful silicon transistors with the letter marking KT or P. Inside they have a large semiconductor wafer capable of generating electric current when exposed to sunlight.

Expert advice: select transistors of the same name, as they have the same technical characteristics and your solar battery will be more stable in operation.

Transistors must be in working condition, otherwise they will be of no use. The photo shows a sample of such a semiconductor device, but you can take a transistor of a different shape, the main thing is that it must be silicon.

The next stage is the mechanical preparation of your transistors. It is necessary to remove the upper part of the housing mechanically. The easiest way to perform this operation is with a small hacksaw.

Preparation

Clamp the transistor in a vice and carefully make a cut along the contour of the housing.

You see a silicon wafer that will act as a photocell. Transistors have three terminals - base, collector and emitter. Depending on the structure of the transistor (p-n-p or n-p-n), the polarity of our battery will be determined. For the KT819 transistor, the base will be a plus, the emitter and collector will be a minus. The greatest potential difference, when light is supplied to the plate, is created between the base and the collector. Therefore, in our solar battery we will use the collector junction of the transistor.

Examination

After sawing off the housing of the transistors, they must be checked for functionality. For this we need a digital multimeter and a light source.

We connect the base of the transistor to the positive wire of the multimeter, and the collector to the negative wire. We turn on the measuring device in voltage control mode with a range of 1V.

We direct the light source to the silicon wafer and control the voltage level. It should be in the range from 0.3V to 0.7V. In most cases, one transistor creates a potential difference of 0.35V and a current of 0.25 µA.

To recharge a cell phone, we need to create a solar panel of about 1000 transistors, which will produce a current of 200 mA.

Assembly

You can assemble a solar battery from transistors on any flat plate made of a material that does not conduct electricity. It all depends on your imagination.

When transistors are connected in parallel, the current increases, and when transistors are connected in series, the source voltage increases.

In addition to transistors, diodes and copper foil, aluminum cans, such as beer cans, can be used to make solar panels, but these will be batteries that heat water, not generate electricity.

Watch the video in which a specialist explains in detail how to make a solar battery from transistors with your own hands:

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Over time, people who are passionate about radio accumulate quite a lot of different electronic parts, among which may be old Soviet transistors in a metal case. They are no longer relevant as radio components due to their large dimensions, but they can be used for a completely different purpose: as a solar battery. True, the power of such a battery is quite small in relation to its size, and is only suitable for powering low-power devices. But you can still assemble it as an experiment and for fun. To convert a transistor into a solar battery, you first need to cut off the cover from it. To do this, carefully clamp the transistor in a yew by the rim on the body and cut off the cover with a hacksaw. You need to do this carefully so as not to damage the crystal and thin wires inside the transistor. After this, you can see what is hiding inside: As you can see in the photo, the crystal is quite small compared to the transistor body, but it is this that will convert solar energy to electrical. Next, you need to shine light on the crystal and use a tester to measure which pins will produce the highest voltage. Its value, of course, depends on the power of the transistor and the size of the crystal. Here is a table of measurements given by the author using the example of the KT819GM transistor: After the measurements, you can begin assembling a solar battery to power the calculator. To obtain 1.5 volts, it is necessary to assemble five transistors in series, with the collector being a minus and the base being a plus. To attach the transistors, a piece of thin plastic was used, with holes pre-drilled for the legs. After installing the transistors in place, they are connected to each other according to the above diagram: As the experiment showed, outdoors, in sunlight, the calculator worked well, but indoors it definitely lacked energy, and at a distance of more than 30 centimeters from an incandescent lamp it refused to work. To increase the battery power, it makes sense to connect five more of the same transistors in parallel. Source Become the author of the site, publish your own articles, descriptions of homemade products and pay for the text. Read more here. 0 Idea 0

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We continue our topic on the construction of a home solar power plant. You can familiarize yourself with general information about the principles of calculation of solar panels, as well as for autonomous power supply systems by reading our previous articles. Today we will talk about the features of self-manufacturing solar panels, the sequence of connecting electrical converters and the protective devices that should be included in the solar power plant kit.

Manufacturing of photovoltaic modules

A standard photovoltaic module (panel) consists of three main elements.

Panel body.
Frame.
Photovoltaic cells.

The simplest design element of a solar module is its housing. As a rule, its front side is an ordinary sheet of glass, the dimensions of which correspond to the number of solar cells.

Adoronkin User FORUMHOUSE

The glass I used was regular window glass – 3 mm (the most inexpensive). I conducted a test: glass degrades the performance of the module slightly, so I don’t see much point in using tempered or coated glass.

Window glass is often used to make protective housing for solar panels. If you doubt the strength of this material, then you can use tempered or regular glass, but thicker (5...6 mm). In this case, there is no doubt that the photovoltaic elements will be reliably protected from destructive natural disasters (from hail, for example).

The back side of the case can be made of moisture-resistant material, which will protect it from dust and moisture getting on the solar cells. This can be metal sheet, hermetically attached to the frame with rivets and silicone, or, again, ordinary glass.

At the same time, some craftsmen do not welcome the presence of a back wall on the body of a homemade solar panel.

Adoronkin

The back of the battery is open (for better cooling), but covered with acrylic varnish mixed with a transparent sealant.

Considering that when the panels heat up, their power drops significantly, such a solution seems justified. After all, it provides effective cooling of semiconductor elements and at the same time high-quality sealing of solar cells. All together is guaranteed to extend the life of solar panels.

Frame

Frames for homemade solar panels are most often made from standard aluminum angles. It is better to use coated aluminum - anodized or painted. If you are tempted to make a frame from wood or plastic, be prepared for the fact that after a couple of years the product may dry out or even fall apart under the influence of climatic factors (with the exception of window plastic).

BOB691774 User FORUMHOUSE

I buy from where the windows are made. Price – 80 rub. per meter The profile is completely ready for work, you just need to cut it at 45° and under heat, glue the corners.

Let's consider the simplest panel option: a panel with an aluminum frame.

The aluminum frame parts are easily fastened together with bolts or self-tapping screws.

Subsequently, the glass body can be glued to the aluminum corner without much effort. All you need for this is regular silicone sealant.

Adoronkin

I took silicone sealant - universal. 1 tube is enough. It is better to take transparent sealant. The chemical safety of the sealant in relation to photovoltaic cells was confirmed by the annual operation of the battery.

The result will be a shallow box with a glass bottom, to which photovoltaic cells will subsequently be glued.

When determining the size of the housing and frame, one should take into account the need for a gap between adjacent photovoltaic cells, which is equal to 2...5 mm.

Soldering solar cells

The most critical stage in assembling solar modules is soldering the photovoltaic cells. Solar cells are made of very fragile material, so they require appropriate handling. Those people who have already dealt with them will henceforth, when purchasing solar cells, order cells with a certain quantity reserve (10 - 15%). For example, to make a panel designed for 36 elements, they purchase 39 - 42 cells.

Thin busbars for soldering solar cells, thicker busbars (with the help of which adjacent rows of panels are combined with each other) and solar cells are best purchased from the same seller. This saves time searching for suitable elements and provides certain guarantees of their compatibility.

Soldering of elements in case of their serial connection is carried out according to the following scheme.

The negative (front) contact of the solar cell is soldered to the positive (back) contact of the next cell, and so on.

This is what the finished panel looks like.

For work you will need the following tools and materials:

Powerful soldering iron 40-60 W (at least).
Flux (flux marker) must be neutral (otherwise the soldered contacts will quickly oxidize).
Tires of different widths.
Rubber gloves - to avoid smearing the solar cells (especially their front part).

We also need tin. This is in case the busbar is poorly soldered to the contacts. The cells being worked with are located on a hard and flat surface. It could be a board or glass. To prevent the cells from sliding on the working surface of the table, they can be fixed using pieces of electrical tape glued around the perimeter of the element. You should not put electrical tape on the cell itself (especially on its front part). The free end of the shank should be attached to the table using double-sided tape.

Soldering of elements and assembly of panels is carried out in the following order: first of all, the contact groove of the plate along its entire length is coated with flux. Then the flat busbar is placed in the groove and soldered to the contact of the plate along its entire width (at the negative pole of the element).

Or at three points (usually at the positive pole of the element).

The number of soldering points depends on the element design.

The contacts are soldered to all solar cells one by one. Additional solder is used only in cases where the bar cannot be reliably soldered to the plate the first time.

First of all, the contacts are soldered to the front (negative) side of each cell, which will rest on the glass body of the panel.

A tire of the required size is prepared in advance. Its length should correspond to the width of 2 adjacent plates.

The plates with soldered contacts are laid face down on the glass body of the panel. After this, they can be soldered to each other according to polarity (“–” of each cell is soldered to the “+” of the adjacent cell, and so on).

To make it more convenient to place the elements on the glass body of the panel, its surface can be pre-marked.

Sliderrr User FORUMHOUSE

I marked the location of the cells on the glass with a black felt-tip pen. I positioned the cells and secured them with heads, nuts and bolts.

Nuts, keys and other metal objects in this case were used as cargo. You can also fix the cells using transparent silicone, which is applied to the glass at the corners of each element.

When connecting adjacent rows of photovoltaic cells, additional solder should be used. This will increase the reliability of soldering at junctions of conductors of different widths.

When all the cells are soldered together, and the conductors are brought out through the aluminum frame of the panel, you can begin to fill the solar cells.

To do this, the seams between adjacent elements are filled with silicone sealant.

Sliderrr

I filled the gaps between the panels with silicone (flattened it a little and cut off the nozzle of the syringe to ensure the aesthetics of the seam and good contact of the silicone with the glass). When it was dry, I coated the perimeter of each panel again. After the sealant had dried, I coated the cells with yacht varnish twice. In the future I will try insulating varnish.

User Mirosh Instead of varnish, he uses white silicone to fill the cells, which he applies to the surface in a thin layer using a spatula. The result is quite satisfactory.

Before final assembly, it is advisable to test each element for the power it generates. This can be done using a multimeter. If there are no significant differences between the current and voltage that each individual cell generates, then you can safely include them in the photovoltaic module.

Installation of Schottky diodes

The design of solar panels often uses elements that we have not previously mentioned. These are Schottky diodes.

They are installed for two reasons.

Firstly, shunt diodes are installed so that in the dark or in cloudy weather the solar panels do not discharge the battery included in the solar power plant.

Alex MAP User FORUMHOUSE

In the case of direct connection of solar panels to the battery at night, voltage drops on the panels and they heat up. Therefore, a Schottky diode was introduced into the circuit of a primitive solar controller, developed 10 years ago (protection against overnight battery discharge).

If a modern controller is connected to the solar panels, then there is no special need for protection against night discharge. A working controller, without the help of additional devices, will disconnect the power supply from the battery in time.

Secondly, if the solar module is covered by the shadow of a nearby building (or other massive object), then the power of this element is reduced. The consequences of the power reduction are as follows: in relation to the remaining panels connected in series to the shaded element, the shaded element turns from a current source into a resistive load. The resistance of the shaded module increases greatly, and its temperature increases significantly.

A significant reduction in power is the most harmless thing that can result from partial shading of a series-connected solar battery. After all, eventually the shaded module will overheat and fail. This phenomenon is called the “hot spot effect.”

In order to avoid this effect, a Schottky diode is installed in parallel with each module connected in series (or a series row of solar cells). The diode allows electricity to bypass the shaded panel. In this case, the generated voltage will decrease, but a large current drop will be avoided.

Alex MAP

The large current from the remaining panels of the circuit, which are illuminated, will not be interrupted, but will bypass the shaded parts of the panels through diodes. The final voltage will be slightly lower, but this is not important to the controller. If the panels did not have built-in diodes, then with the slightest shading of even a piece of 1 panel, the entire chain would completely stop producing current.

In other words, power losses will be commensurate with the shading area.

Diodes can be installed parallel to the entire module, or parallel to its individual rows.

Here is a diagram in which each row of cells installed in one module has its own diode. In practice, the module is most often divided into 2 equal parts.

HouseR User FORUMHOUSE

Typically, for a four-row panel, a midpoint is displayed, that is, the cells are bridged in half. The diodes are placed in the terminal box.

In any case, all solar panel modules should be positioned so that the light hits them evenly. Then you won’t have to solve the problem of shunting individual modules or even cells.

For convenience, terminal boxes are located on the back side of the solar panels.

If several series-connected groups of panels are connected to the controller in parallel, then in this case each serial chain is connected to the common circuit through an isolation diode. This allows you to avoid losses due to mismatch of individual serial chains and additionally protect the battery from discharge at night (if, suddenly, the controller fails).

Diodes are selected according to two main parameters: the maximum current that will flow in the forward direction (forward current), and the reverse voltage. The maximum reverse current voltage (Urev.max.) should not lead to diode breakdown. In this case, the performance characteristics of the diode should slightly exceed the panel rating (about 1.3 - 1.5 times).

But there is one trick here.

Max94 User FORUMHOUSE

There are no normal Schottkys for high voltages. These are just poles with a direct current fall. So it’s better to take regular ones from Urev. Max ≈ 30...100V.

Installation of panels

How to mount the panels correctly and where to install them? The answers to these questions depend on the design of the security systems and the capabilities of their owner. The only thing that everyone without exception should take care of is maintaining the angle of inclination. For each region this angle will be different, and it depends directly on the latitude of the area.

On average, in winter the angle of inclination should be 10°...15° higher than the optimal value, in summer - by the same amount - lower. can be viewed in the FORUMHOUSE section.

Conductor cross-section

In accordance with the postulates of electrical engineering, too small a conductor cross-section can lead to overheating and even fire. Too large is not bad, but it will lead to an unreasonably inflated increase in the cost of the autonomous system. Therefore, the task of its creator is to find a “golden mean”.

Let's start with the fact that the thickest conductors should be installed in the circuit connecting the battery to the inverter (by the way, the shorter this section is, the better). This is where high currents flow.

The conductors connecting the panels to the inverter, as well as connecting the panels to each other, can be selected with a small cross-section. These sections of the circuit may have a relatively high voltage, but there will always be a low current.

HeliosHouse User FORUMHOUSE

16 mm² is not needed and 10 mm² is not needed. 4 is more than enough. A “thick” wire will only be needed in the inverter circuit; the cross-section must be selected in accordance with the current power.

“Thick” and “thin” are flexible concepts, so let’s not deviate from the standards.

Considering that it is currently prohibited to use aluminum conductors in home power supply systems, the tabular data applies to copper conductors with polyvinyl chloride or rubber insulation.

Also, when choosing conductors, you should pay attention to the recommendations of the manufacturers of inverters, controllers and other devices involved in the system.

Automatic circuit breakers

In the circuit of a solar power plant, as in the circuit of any other powerful source of electricity, it is necessary to install protection against short circuits. First of all, circuit breakers or fuse links must protect the power cables running from the batteries to the inverter.

Leo2 User FORUMHOUSE

If something shorts out in the inverter, then it’s not far from a fire. One of the requirements for battery systems is the presence of a DC breaker or fuse link on at least one of the wires and as close as possible to the battery terminals.

In addition, protection is placed in the battery and controller circuit. You should also not neglect the protection of certain consumer groups (DC consumers, household appliances, etc.). But this is already a rule for constructing any power supply system.

The machine installed between the battery and the controller must have a large misfire current reserve. In other words, the protection should not operate accidentally (when the load increases). Reason: if voltage is supplied to the controller input (from the power supply), then at this moment the battery cannot be disconnected from it. This may cause the device to malfunction.

Connection procedure

The electrical circuit is assembled in the following order:

Connecting the controller to the battery.
Connection to solar panel controller.
Connection to the controller of a group of DC consumers.
Connecting the inverter to batteries.
Connecting the load to the inverter output.

This connection sequence will help protect the controller and inverter from damage.

You can learn from the participants of our portal by visiting the corresponding topic. For those who are seriously interested, we recommend visiting another useful section dedicated to sharing experience in this area. In conclusion, we bring to your attention a video that will tell you how to properly install and connect solar panels.

The most popular alternative power sources on the market are. These sources use the effect of generating electric current when solar energy is applied to semiconductor structures made from pure silicon.

The first solar photoplates were too expensive and their use for generating electricity was not profitable. Technologies for the production of silicon solar cells are constantly being improved and can now be purchased at an affordable price.

Light energy is free, and if mini-power plants based on silicon elements are cheap enough, then such alternative power sources will become cost-effective and will become very widespread.

Suitable available materials

Diagram of a solar battery using diodes Many hotheads ask themselves the question: is it possible from scrap materials? Of course you can! Many people still have a large number of old transistors from the times of the USSR. This is the most suitable material for creating a mini-power station with your own hands.

Stages of manufacturing a transistor model

Selection of parts

The most suitable for the manufacture of solar cells are high-power silicon transistors with the letter marking KT or P. Inside they have a large semiconductor wafer capable of generating electric current when exposed to sunlight.

Expert advice: select transistors of the same name, as they have the same technical characteristics and your solar battery will be more stable in operation.

Preparation

Clamp the transistor in a vice and carefully make a cut along the contour of the housing. You see a silicon wafer that will act as a solar cell. Transistors have three terminals - base, collector and emitter.

Depending on the structure of the transistor (p-n-p or n-p-n), the polarity of our battery will be determined. For the KT819 transistor, the base will be a plus, the emitter and collector will be a minus.

The greatest potential difference, when light is applied to the plate, is created between the base and the collector. Therefore, in our solar battery we will use the collector junction of the transistor.

Examination

After sawing off the housing of the transistors, they must be checked for functionality. For this we need a digital multimeter and a light source.

We connect the base of the transistor to the positive wire of the multimeter, and the collector to the negative wire. We turn on the measuring device in voltage control mode with a range of 1V.

We direct the light source to the silicon wafer and control the voltage level. It should be between 0.3V and 0.7V. In most cases, one transistor creates a potential difference of 0.35V and a current of 0.25 µA.

To recharge a cell phone, we need to create a solar panel of about 1000 transistors, which will produce a current of 200 mA.

Assembly

You can assemble a solar battery from transistors on any flat plate made of a material that does not conduct electricity. It all depends on your imagination.

When transistors are connected in parallel, the current increases, and when transistors are connected in series, the source voltage increases.

In addition to transistors, diodes and copper foil, aluminum cans, such as beer cans, can be used to make solar panels, but these will be batteries that heat water, not generate electricity.

Watch the video in which a specialist explains in detail how to make a solar battery from transistors with your own hands:

But that was a ready-made solution.

Now I will tell you about my experience in creating DIY LED solar battery.

Please note that the article is marked with symbols ƒ↓ (the experiment was unsuccessful). Before starting work, I like to look at similar crafts and evaluate who has done what. Here is the topic of one forum, where this question came up earlier, but no one took it upon themselves to implement it and make a detailed review of the efficiency of LEDs.

Personally, the idea came to me completely by accident, just as accidentally as I happened upon someone else’s couple as a free listener. They talked about LEDs and the possibility of using them as photodiodes. That is, in other words, LEDs too convert light into electricity!

First you need to determine which LEDs are best to use. But now is not the season and it won’t be possible to test in direct sunlight, and it’s not constant sun. What to do? Forget Forget until summer? This is not the approach of brainiacs and all do-it-yourselfers))

The halogen lamp purchased in the article about comes into play.

The halogen lamp was not chosen by chance, but due to its proximity to the solar radiation spectrum and high power.

I decided to collect and unscrew everything somewhere LEDs, which were in our Mozgochin laboratory.

For maximum comparison accuracy all LEDs were brought perpendicularly and close to the center of the lamp. But before you look at the table, choose, based on your personal knowledge and experience, which LED produces the highest voltage? White, red, maybe infrared?

5 mm	Volt
Green opaque LED	1,51
Green transparent LED	1,48
UV LED	0,11
Infrared LED	0,93
Red transparent LED	1,37
Orange opaque LED	1,52
Red translucent LED	0,52
White LED	0,32

3 mm
green opaque LED	1,52
green opaque with reflector!!!	1,57

10 mm
Red opaque LED	1,16

Who made the wish green, that’s great!

Therefore, we select all green indicator diodes.

Next I soldered 9 LEDs sequentially and further 9 in parallel to compare the efficiency of 2 types of connection. I stopped at 3 mm because... they produce the same voltage as lights 5 mm each (oh, this word infuriates me).

The results came out as follows:

When connected in series, only 1.25 V

parallel 1.56 V. I expected something completely different. It was not possible to measure the current strength (due to my multimeter). But I already know that it is negligible there. Interestingly, with a series connection the voltage only decreased. Maybe this is due to the fact that LEDs partially consume energy, which they themselves convert from light!?

In general, the professor’s words (from 1 F:))) were confirmed and nothing came of it. But to make sure of this for sure, I connected the LEDs to an electronic thermometer, which is powered by 1 1.5-volt tablet. AND…. drumroll …

Nothing.(

Epic Fail!

Conclusion: The p-n junction area of LEDs is very small (compared to a solar battery). For example, a strip is several centimeters long.