Joule Thief and its Applications

Abstract

In this rapidly evolving world where the technology is flourishing at an exponentially steady rate the need and the requirement for various distinct and efficient sources of energy has become a significantly crucial requirement to fuel the technology of the world to come. We as consumers use an extensive array of devices and appliances in our day to day lives which are powered by discrete kinds of batteries and power sources which till date haven’t been able to be utilised to their superlative potential. The battery resurrection circuit can be implemented on a variety of appliances and devices to utilise the complete capacity of the cells and batteries they use to provide a more economical and efficient use of a battery.

Introduction

I. INTRODUCTION

After creating machines and devices that use electricity as a medium to operate, we humans discovered and optimised various natural and unnatural sources of energy to fill the ever proliferating need of fuel and power. All the various sources of energy that have now been refined to some extent are still lacking, since an immense amount of this energy is left unutilised or untapped. Similarly, the various different kinds of cells or batteries (Lithium Ion Polymer, Lithium Ion, Lead Acid, Nickel-Metal Hydride, Nickel Cadmium) that are now used to power our daily use devices can only power them for a brief amount of time since only a particular capacity of the battery is actually utilised to power the device and the rest is wasted when its replaced as it can no longer be used to operate the device it was designated to power.

II. CIRCUIT DIAGRAM & WORKING

III. APPLICATIONS

A. Using Joule Thief Circuit with Peltier

Free Energy in this case is the body heat which is generated by the body as long as you live to perform various biological processes. The circuit makes use of the Peltier effect (Also called the thermoelectric effect, it is the direct conversion  of temperature difference between two metal to electric voltage) to use the temperature difference between the body and the environment (Usually 30c) to generate electricity which in this circuit is used to drive a LED (Light Emitting Diode). A N-channel junction FET:2SK170 is used to achieve the self- starting oscillation even at a voltage as low as 30mV. The circuit only uses (4.2 mA at 60mV) input. The open circuit voltage is around 8-8.5V with two LEDs connected in series it is around 4.3V. The circuit show above has the ability to function with just a single FET:2SK170 but 4 FETs connected in a parallel combination are used in this circuit to increase its efficiency which also increases the current draw to 4mA. A toroid ferrite core wound with copper wire of different lengths and thickness (100 turns 32Awg & 4 turns 18Awg) is used in the circuit to store the electromagnetic energy. As output two LEDs in series combination are connected to the output terminals of the circuit.The circuit shown below (Fig 3) demonstrates an example cum application of how merely the heat perpetually radiating from one’s body can be used as a constant source of energy supply to power devices of the future and lend a helping hand towards diminishing the rising energy crisis. This mechanism could also prove to be profitable and advantageous when applied at places where the wasted energy after the completion of a particular process or processes is in the form of heat radiation, as the greater the temperature difference between two metals the higher is the voltage generated by this circuit.

B. Using Piezoelectric Discs with Joule Thief to Charge Up Batteries

A piezoelectric disc (usually made of Rochelle salt (KNaC4H4O6·4H2O), Tourmaline, Topaz etc) when put under mechanical stress converts this mechanical energy to electrical energy and induces a certain amount of voltage which can be collected, stored and used as a power source to power or charge various devices. The piezoelectric disc being very useful is still lacking since the output it generates is too less to be used as optimal power source. However, if used with a joule thief circuit the output can be amplified and actually be used as a power source for various small-scale appliances. Since the actual construction of the joule thief is very cheap and easy to mass-produce commercially it could be a great alternative to be paired with a set of serially connected piezoelectric discs (connected in a serial combination to increase the EMF generated) and hence used as a power source at places where the wasted energy generated is in the form of mechanical stress or a deforming force to get the most effective use of it.

C. Using Joule Thief for Wind Power Generation

The circuit shown below (Fig 4) is an example of how the rotation of a dc fan through passing wind can be used as a power source to drive a LED. We know that a LED requires a minimum input of 3V to light up but the voltage generated by the rotating fan is far less than that, therefore the fan can directly be connected to a joule thief to gain a viable output that will be sufficient enough to light up the LED. Similarly, this circuit can also be modified by replacing the led with a rechargeable battery circuit to help store the generated electricity and charge up a battery that can be later used to power other appliances. The low voltage input by the fan in this circuit is amplified to a series of high value DC voltage. The Joule thief circuit can be used in similar applications like these, for example- It can be used in dynamo mechanisms like using the rotational movement of ceiling fans to drive another motor (which will be the input end) between which the joule thief can be connected and at the output end other appliances or cells can be connected as per the user requirement. Similarly, this mechanism can be used to harvest energy from the rotational motion of car tyres, water turbines or almost anything that involves rotational motion.

D. Other Miscellaneous Applications

1. Using joule thief circuit with solar cells (converts solar energy to electric energy) to power appliances and/or charge rechargeable batteries.
2. Using Joule thief circuits in bicycle lights, portable reading lamps, portable heaters, remote controls and other small appliances that are powered by conventional Li-OH batteries.
3. Using the Joule Thief circuit with car batteries, CFLs, power tools, decoration lights, etc.

IV. RESULTS & DISCUSSION

The Joule thief can be proficiently used by modifying various circuit parameters (like number of turns on the toroid core, types of transistors used, turns ratio on the core, etc) to extract and utilize the full capacity of various different kinds of batteries outputting different voltages. The joule thief can also be used with various kinds renewable sources of energy to collect and store energy in the form of electricity and use it to charge up batteries or operate appliances.

V. FUTURE SCOPE

With significant improvements to the circuit components in the future this circuit can be used with various complex devices such as smartphones, tablets, smartwatches, laptops, portable power banks, etc to increase their battery lives and make complete use of the battery cycles of the rechargeable batteries (Lithium Polymer batteries) that they use.

Conclusion

In our day to day lives where we are completely enveloped by a plethora of devices the joule thief circuit could be evolved and improved to be implemented on a wide variety of appliances. Using the joule thief circuit in various kinds of small circuits and devices can help users save a substantial amount of money in the long run since the appliances when used with the joule thief will be able to utilise the complete capacity of the batteries giving the consumers a longer lasting usage and preventing the unnecessary wastage of energy. Furthermore, the reason joule thief could be easy to implement commercially with a variety of devices is because it is relatively easy and substantially more economical to mass produce since it requires just a few components to function and can be modified appropriately for different applications.

References

[1] Wikipedia Joule thief - Wikipedia The Free Encyclopedia [online]. 2012. http://en.wikipedia.org/wiki/Joule thief [2] electronicGURU, https://www.instructables.com/id/Joule-Thief-Circuit-How-to-Make-and-Circuit-Explan/ [3] Jason Poel Smith, https://makezine.com/projects/joule-thief-battery- charger/ [4] J Sujatha, Pradeep Baurai, “A Review on Joule Resurrection Circuit and its Applications”, 2018, ISSN NO. 2249-7455 [5] Gagyo tech, https://www.kickstarter.com/projects/1390681402/ko ma-d-type-battery-powered-vehicle-jump-starter [6] Ouzcoskun, https://forum.allaboutcircuits.com/members/ouzcosk un.346905/ [7] Karras, Phil 2014. \\\"Joule Thief Information Page.\\\" Circle Science Consulting Site, January 20.

Copyright

Copyright © 2022 Rishabh Chopda, Alisha Gupta, Palak Kabra, Pratibha Dwivedi. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.