Radiant Charger for 1.5 - 9 V Batteries

[boguslaw]

Hi Skaght!
For me after some test, i have great result with these component:
Transistor 2sc3552
Diodes uf5408
My core are a 6 inch ferrite rod
My bi-filar wire are twist together (litz style) before wound on the ferrite.

Unfortunately, i dont have a scope so i cant see the real voltage spike. But i think we can have a good idea of the voltage spike using a simple multimeter at the output by connecting the + input on the - output while re-emf is running but this will highly increase the amp draw from the source... This way it a bit like "Alexkor radiant charger" chapter 6 PJK book.
I dont know why but the Re-emf give me beter result than the Alexkor.... Right now im tring it with solar panel and it seem a realy good idea!
Enjoy!

How many turns or coil twisted wire ? I tried Rene circuit but I saw no spikes on scope , seems that my transistor is not oscillating (MJE3055)

[skaght]

I used a ~3" ferrite core, about 1/4" diameter 30 turns of 20 gauge magnet wire. It spikes, however the charger works as a DC charger even if it's not spiking. I ran some tests last night about efficiency and I switched over to straight DC charging for a comparison. Amp for amp, it's approximately the same. I think it comes down to the fact that most pulse chargers I've made aren't very efficient, so this one seemed impressive initially.

The first transistor I got to work was an MJE3055, so they can oscillate in the circuit.

Edit 4-21: I will say that this little charger is bringing some pretty dead lead acid batteries back to life. With such a simple build, no moving parts and nothing that gets hot, it's definitely a keeper. I'll probably build a permanent version at some point since I usually only breadboard my experiments.

[Wistiti]

Spikes...

hi Boguslaw,
I did not count the turn but i completly cover the rod (jus one layer) with twisted 19 AWG wire so maby 80 turns... I think it's like a simple joule thief... the more turn you have the higher the voltage spikes are.
To see the spikes on a scope do you try to connect the scope probe on the negative charging battery and the colector of the transistor... for me this way i can see the frequency on my normal multimeter and it vary betwin 7khz to 30khz depend of the pot adjustment and the charge of the battery...

Ciao!

[adversarius]

charging multiple batteries

I want to hook up a couple of 1,5 Volt batteries in parallel (or in series) to charge them at the same time, but I am asking myself if this is a good idea. Should the batteries do not have the same voltage level those with a higher level could be overcharged in the process. Is there risk of overcharging with this and how can it be reduced to a minimum? (I'm referring to Rene's charger circuit)

Regards

[wsxian2]

Checking the charger

I have a question on the Rene Charger.
How do measure the voltage going to the battery?
I have put my voltmeter across the Plus and Negative of the battery being charged, but the most I have seen going into the battery is 19 volts.

In a youtube video, newest test Bedini solid state - YouTube I see a guy getting about 300 volts and he shows it on a volt meter. This is with another battery charger setup.

Where do you make the connection to see the voltage?
I do not have a scope, just voltmeters.

I got my Rene circuit from this youtube video: Joule thief - RE-EMF Charger - by Rene - YouTube And the parts listing from this forum thread.

Hopefully it is correctly put together!

[gyula]

Hi wsxian2,

Source battery #2 should have a higher voltage level all the time during the charging to maintain oscillations i.e. charging. In the Rene circuit a 18V to 20V source feeds the circuit and the charging battery is a 12V type, the 6 to 8V difference is needed to run the oscillator circuit.

What is the resting voltages for the two batteries? Especially for the charging battery #1 when you disconnect it from the circuit?

It sounds okay to measure voltage across the battery as you described.

Gyula

[totoalas]

Monster ss ssg by cool joule @ 240 mA charge my 3 60 ah batteries supplied by one 18 v 60 w solar panel / and or ssg motor with 2 10 w in series

totoalas

[Parav]

Monster ss ssg by cool joule @ 240 mA charge my 3 60 ah batteries supplied by one 18 v 60 w solar panel / and or ssg motor with 2 10 w in series

totoalas

Hi Totoalas,

Can you show us schematic of this one--it sounds like you have a good set up there.

Much appreciated -in advance,--regards,--Paul

[totoalas]

Hi Totoalas,

Can you show us schematic of this one--it sounds like you have a good set up there.

Much appreciated -in advance,--regards,--Paul

Below is the ckt I used from Eshanco by Minoly

http://www.energeticforum.com/171004-post858.html

[Berg]

Very Simple Circuit

I don't know if this circuit would work for what you are trying to do.

Anyhow, you could consider switching out the charging capacitor for a charging battery.



Regards,

Berg

[SkyWatcher]

Hi folks, just built the rene/joule circuit.
It works good, only downside, is if you're trying to charge a very sulphated battery, it jumps up to the source voltage, which means there is no net voltage across the joule thief part of circuit, so no pulsing or charging.
Otherwise, patricks circuit or alexkor works good also.
peace love light
tyson

[qbjorn]

Hi folks, just built the rene/joule circuit.
It works good, only downside, is if you're trying to charge a very sulphated battery, it jumps up to the source voltage, which means there is no net voltage across the joule thief part of circuit, so no pulsing or charging.
Otherwise, patricks circuit or alexkor works good also.
peace love light
tyson

Easily remedied - just add a small light-bulb across the battery as an initial 'starter' and remove it once the impedance of the battery has lowered enough to drive the Joule thief on its own.
My Joule thief normally draws 0.1A for a 7Ah battery so the bulb should be in the order och 1-2W to start things.
It might be necessary to reduce the input voltage a little during this start-up to avoid over-voltage on the lamp.

[SkyWatcher]

Hi qbjorn, thanks for remedy.
Reminds me of the 3bgs thread, where they put a load on dead batteries to keep it running.
Will try it, though not sure about this particular 12 volt SLA here, found it in someones garbage, battery jump starter unit, seems like 3 of the cells might be shorted or damaged, it sits at around 6 volts, thanks.
For those interested, used 4 ferrite beads glued together, 4 bifilar layers of 24awg. magnet wire, which is around 300 bifilar turns.
peace love light
tyson

[wsxian2]

too much?, also my experiences with recharging

I am using a 24v scooter motor charger as my power supply (PS) and it will put out as much as 28 volts (max of 2.5 amps per the description on the PS).
I am wondering if this is just too much?

I have been trying to charge up some 1.5v batteries. Plain, alkaline, Nickel Hydride and rechargeable alkaline.
I have had two pop on me, so be careful!
It only takes a minute or two to charge a 1.5v battery. If it gets warm (some get warm or hot very quickly), take them off, let them cool and try again -otherwise they will pop, just from the heat - like popcorn!
Some just won't work even if charged (they show 1.5v but when put in a flashlight, there is no light).
Some won't charge- they stay zero or 0.1v.

You just have to experiment. Wear safety goggles!

I have used a wheat bulb (neon) across the C and E on the 2N3055 and some times, the wheat bulb is dim and that is when I get my best charging (turn your variable resistor one way or the other to get the dimming). When the wheat bulb gets real bright, the charging goes down. You can get a wheat bulb or just use any neon bulb like from an AC tester, or even a night light.

If you have a radio handy, you tell by the interference when your charger is really charging (the more noise/static you hear, the more it charges).

Just a note that the charger may not charge for a short time when you hook up your battery. It takes a short period of time before the circuit starts to oscillate. The bulb or radio interference can be used to determine if really charging.

I have also used the charger on some electric drill batteries. And they are ok. One has a lot of torque (14v), and other has normal torque (7.4v) - that may just be related to the current coming out of the batteries.

I got my parts at Radio Shack, but some of my wiring from Lowe's and that wire is not workable as it won't solder - think it was for car audio and designed for non-solderless connectors.
So I opened up a Power Supply (PS) from an old computer and used the wires from the PS and they solder ok.
I go a heat-sink from the PS circuit board and used it on my 2N3055 (after some re-drilling), and boy that heat-sink can get hot! So can my toroid (which I got from the PS too).

I wish I could get the entire circuit into a box, but with the heat-sink producing so much heat, I am not sure what kind of box would take the heat.

Just giving my experience with the circuit.

[SkyWatcher]

Hi folks, Hi wsxian2, I'm also using the 2n3055 and it runs cool without a heatsink when charging a 12-7ah SLA, though it is only drawing 180 milliamps as it is setup right now, 1500 ohm base resistor.
So 3.42 watts input, though the real power input across coil and charge battery would be 1 watt if we consider 6 volt difference, 19 volts minus 13 volts.
Your primary winding may be too low a resistance.
I first started with one layer of 18 awg. and that caused the 2n3055 to get way too hot, so used the 4 layers of 24 awg. and works good.
I'm using a 19 volt laptop power supply and the somewhat sulphated SLA shot up to around 19 volts from around 10.5 volts, though it still managed to oscillate and the battery voltage slowly dropped and is now sitting at 13.25 volts after many hours of charging.
Just turned off charger and its sitting at 12.72 volts, will see where it settles out and how it takes a load.
Seems like a fairly good charger so far, for certain uses.
Though if one were to charge a 1.5 volt nimh, i would use a 6-7.5 volt input.
I use the alexkor, air coil, high frequency pulser to charge 1.5 volt alkalines and have never had any leaking issues or heat and use a 6 volt input with the alexkor for the 1.5 volts.
peace love light
tyson