Joule thief unity recharger.

[stevensrd1]

A design that uses two AA batteries in series to power a joule thief led light while at the same time recharging two AA batteries in parallel. Of course you can only swap the draining and recharging batteries in this design several times. As there are small losses in energy transfer. Mainly because the wire is not superconductive wire, nor the circuit or the batteries superconductive. Otherwise you would be able to swap the batteries forever. http://youtu.be/hltAVunhfR8

[MarkE]

It is readily demonstrated that for a given light output of a given LED, a competently designed circuit that only drives the LED will exhibit a longer total run time from a pair of initially charged batteries than will one that charges cells which get swapped out as the first set of cells deplete.

[Magluvin]

A design that uses two AA batteries in series to power a joule thief led light while at the same time recharging two AA batteries in parallel. Of course you can only swap the draining and recharging batteries in this design several times. As there are small losses in energy transfer. Mainly because the wire is not superconductive wire, nor the circuit or the batteries superconductive. Otherwise you would be able to swap the batteries forever. http://youtu.be/hltAVunhfR8

Tito said something one time that sorta clicked for me here.

One time, he had suggested a secondary with only a few turns more than the primary. That was all he said.  If we think about it, say we use a 12v batt to drive the primary, the sec should put out something just above 12v that should be able to charge the primary battery. And it would have more current than a sec of 2 or even say 10 times the turns on the sec as the pri, even though the voltage is way higher. Current is the key to charging a battery. As long as the charging voltage is just above the source, current will flow to the source. Then say we make our sec of heavier wire than the primary to have its resistance equal to or lower than the primary, just a bit, just like only adding a bit of extra turns on the sec than the primary.

So far, it seems very high voltage produced by outputs, dont charge batteries as much as what was used to do the charging.

Think. Why is it that we see these circuits taking from 1 battery to another then switching the batteries positions for source to charge? Why not just send the output back to the source battery? The sec can be isolated from primary circuits. So far, battery swapping tends to show lower and lower charge in both batteries over time. So if there is at least some valuable charge ability from the circuit, send it to the source, then we should see a source battery that lasts longer, instead of doing swaps. But for some reason, people tend to 'resort' to battery swaps. Possibly because it can hide noticeable losses by jacking up the charge batteries voltage higher than the source started with for x amount of swaps, and neglecting the greater loss of the source batt in order to do so.. But they always seem to diminish over a period of time.

Just a thought.

Mags

[Magluvin]

More thinking...

Lets say we wound an ecore transformer.  If we wound a secondary first on the bobbin, say 40 turns. Then wind the primary 36 turns on the sec , sec is inner dia winding and the pri is the outer diameter winding. Being the sec was wound on the inner diameter, the length of wire is shorter(same awg for pri and sec) than the primary of 4 less turns. Can be done on a rod core. From what I understand, if the pri is the outer winding to the sec, the sec doesnt affect the primary as much as the pri affects the sec.

Mags