The idea came to me when i was ready to replace a battery cell in my alarm clock next to my bed. Even i am using the last 5 years only rechargeable batteries of the most types i considered how many battery cells people around the world throw away in a simple move like that i did now.....How meny disposed battery cells thrown away in each household? Who knows? But what if we had a rechargeable system to recharge batteries when the device is connected to an outlet and when we will need the battery (In a black out) this will continue working the device.So first we will have power continuity, second we will save money buying and dispose all the dead batteries, and third under normal conditions we can rechargeable any type of battery we like. My next question to my self was that this kind of circuit must be simple, cheap, realible, and easy convertible to recharge any battery cell and giving power to a device at the same time. SimpleEhhh????
So i tried to recall my studies from university and i reminded a very simple circuit which actually recalls all the science of electricity and every 1st year stuedent knows well.
Materials..... Cheap and Easy
>>4 diodes of 1N 4001 type for making the bridge which conncects to the transformer
>>a transformer 2x6 if you want to recharge batteries from1-6VDC or 2x12 for devices up to 12VDC (input 220VAC europe output 2x3,2x6,2x12 choose your one)
>>a 1000uF Capacitor, using it as a filter and elevator of the power
>>a Relay (6VDC if you will give power from 1-6VDC or a 12VDC if you like to recharge a 12VDC battery)
>>a resistor of 33 or 39 Ohm /5W (5W is ideal because the resistor cool down faster)
>>a diode of BY251
>>2 rca female for chassis
>>2 rca male
>>a prototype card or a perforated card, no PCB needed
>>a nice box for the battery recharging docking station appx12cm X 5cm X 3 cm ( in this box you will try to fit a transformer, the basic circuit , cables, the battery nest and your spirit! :D
All materials costed to me 12euro (15USD) The most expensive is the transformer.
Lets go now at the circuit design and i will explain to you....