25 Amp Hour Battery Charging a 50 Amp Hour Battery With Near Zero Loss.

I have long been working on a battery to battery charger, with lots of testing to prevent skin effect. The nice thing about battery to battery charging is that you do not need wind or solar. Many people have been working on this concept for decades now. YouTube videos date from about 2010 or so.

Bedini is probably the most famous for his Simple School Girl circuit, which charges batteries, but is actually desulfinating lead acid batteries. To me, that means it is not suitable for continuous use because it will eventually destroy the battery. So, I have been working on and looking for an alternative.

To his credit, Bedini did have a patent on a schematic to harvest back EMF (see Fig 2) that hardly anybody uses. I use something similar, and test extensively for skin effect and amp hours in and amp hours out.

My testing shows that if you leave the run battery connected to the circuit on the negative and let it rest, the run battery will eventually recover some of the loss from what I presume is the still coming from the coils.

So, I was excited to see this tuning video from Wind Power and More. The idea behind many battery to battery chargers is to use pulsed motors in order to enable capture of the back (or counter) Electromotive Force (back EMF). 

TUNING

In this video Wind Power and More explains the tuning that you should be looking for when capturing back EMF. Such as:

  - Using Pulse Width Modulation (PWM)

 - Using a 12 volt regulator when using larger batteries, such as a 24 volt system

 - How to change the resistors for your particular configuration.

In previous videos, he shows "How To" build the PWM circuit, coils, "How To" build the rotor, and shows the Back EMF on the oscilloscope. (Single waves with flat ends... etc)..

The Details:

START:

25 amp hour run battery begins at 26.6 volts. Meter is at zero (0) amp hours and zero watt hours at start.

50 amp hour charge battery begins at 26.2 volts. Meter is at zero (0) amp hours and zero watt hours at start.

50 amp hour charge battery is taking in about 12 watts. Load is two 5 watt LEDs.

The run time is about 2 hours for this video.

Wind Power and More tells me that:

"These are lifepo4 batteries they are fully charged resting voltage is 26.6 to 26.7 volts. 26.4 is not fully charged"

END:

25 amp hour run battery begins at 26.5 volts. Meter is at 0.04 milli amp hours (0.0004 AH) and zero watt hours at end.

50 amp hour charge battery ends at 26.4 volts. Meter is at 1.03 amp hours (1.03 AH) and zero watt hours at end.

Essentially, by my calculations, he is getting 2,575 Amp Hours charging output for every Amp Hour in. (That's not including the 10 watts LEDs output run time for 2 hours.)

Terrific video, with no BS.

by Wind Power And More

"Fine tuning the circuit made a HUGE difference.All the details included in this video"