At the person who is outside the big city, the need for additional electric energy sources arises rather often. One of possible options – the solar battery. Of course, in country conditions you will hardly manage to make the powerful battery capable to provide with the electric power all site. But there will quite be enough power to charge the mobile phone or even to connect the small fan.
The battery from old calculators
There are models of calculators on solar batteries. As a rule, such battery consists of three photo cells. Sometimes they happen more. Elements need to be taken and so that to keep the connecting wires soldered to element or fixed on it by means of clips. It will significantly facilitate mounting. Production of self-made power supply very much requires also sensitive measuring tool – for example, multimeter. Single element gives the following quantity of the electric power with 1 sq. cm of the area:
- current up to 24 mA;
- voltage is 0.5 V.
Under loading half of tension will turn out that for practical purposes it is absolutely not enough. If the bigger tension or bigger current is necessary, it is necessary to connect several such elements among themselves. The general panel from dielectric is for this purpose necessary (for example, textolite). Serial connection (with obligatory respect for polarity) will give the chance to increase voltage output, but the internal resistance of photo cells is quite high. Parallel inclusion of separate elements also is useful to apply to its decrease (and increases in output power of the battery). In parallel it is possible to connect both chains of consistently connected battery cells, and separate elements to each other.
Anyway it is necessary to monitor respect for polarity. If it was succeeded to keep the wires attached to separate plates, to solder elements quite easily, but it is necessary to do it with use of the heat sink. But at extraction of photo cells it is possible to keep wires not always. In this case it is possible to apply spring clips and even small springs from ball pens. Just by the same principle it is possible to assemble the solar battery from selenic plates from old photoexposure meters.
The element cannot be soldered as in house conditions it will lead, most likely, to breakdown.
Old radio components or unnecessary computer mice
Most often at hand there are no ready photo cells. In this case it is possible to use the available old radio components. For example, having connected consistently 20 dot diodes in the glass body (for example, D9, D2), it is possible to receive tension 1.2B. Certainly, respect for polarity is necessary and in this case. If the body of the diode is coated, it needs to be washed away or scratched out. Diodes approach any, both silicon, and germanic. Additional parallel coupling of diodes and chains of diodes just as in the first case, help to reduce the internal resistance of the battery. With the same purpose it is possible to use photo diodes from the failed computer mice. Possibly and use of LEDs which can also work as photo cells.
The battery from transistors
Instead of diodes it is possible to use transistors with the metal body. Here for access of light it is necessary to remove the metal body or its upper part. It is possible to use transitions the collector - base and the emitter - base. In this case both silicon, and germanium transistors, transistors with the torn-off collector or the emitter approach, but it is desirable that they were same. Rules the same connections that are specified in the first two ways. Use of the additional reflecting panels rejecting light on the solar battery is useful.
The transistors are more powerful, the bigger current can be removed from the battery.
Some subtleties
Transistors, as well as in general any photo cells, it is desirable to protect from mechanical damages and hit of dust. For this purpose it is the best of all to close the assembled battery from above. The transparent film or thin quartz glass approaches. It is possible to apply and thin orgesteklo. Normal window glass or, say, triplex, do not approach as detains ultraviolet rays. It is important to provide correctly position of the battery concerning the sun as the efficiency of its work depends on it. Efficiency of the solar batteries made houses quite low also does not exceed 10%. It is possible to receive the electric power and not on very sunny day, but the battery should not be in strongly shaded place. There will be enough tension to charge accumulators somewhere at the dacha or in campaign. By the way, in such a way it is possible even to light the dark basement if outside to arrange the battery, and inside – LED.