Is there any way a battery can charge other battery through isolated Charging circuit powered by a battery?

a battery charger doesn`t care Where it gets its power from, be it mains, solar or another battery, as long as it`s capable of supplying enough power, a regulator can be made to charge a battery from such supply.

Thanks YT2095,  I am thinking of developing a power supply that will work for a very long time if not forever when the components are capable of working forever, the system will involve 2x 12 volts batteries which could be of any amp, and 2x charger circuits, each of the charger circuit  will be simultaneously switching over in charging each other battery cells while both of them will power a load in a consecutive time, at this stage an MCU will be design with program to monitor ther charging period of one of the battery also enable the system to switch over the charger to the exhausted battery while the already charged battery will simutaneously take control of powering the same load.

I would prefer that each of the power charging source to be on battery, only not solar because I presumed that the solar energy will sometime become weak mostly at night time, the intension of this project is due to an interrupted power supply in a developing counteries or in a remote rural villages that never have access to their own National Electric power supply . What do you think about   this?

I think I understand, it`s basically a UPS, with a spare back-up battery, so while one is in use, the other is charging, and when charged it will swap over with the other battery to charge that.

I do something similar here in the Lab, only I took the internal battery leads outside of the UPS case, and swap the batteries manually when needed.

Yes it is similar function as the UPS, but the main technology invole is to electronically swap the battery lead to a charger circuit with the means of Microntroller to sence the limit in chargered current and simultaneously swap the charger circuit to the  empty battery, I also presumed that the both batteries will continually tied to the load in parallel connection, or will be a good ideal to interchange the Ouputs to a load?.

Best Regards.

If I were to do that, i think I would leave the GNDs (the - terminals) common, and just switch in/out the Positive leads, probably with power relays as a Flip-Flop arrangement.

your MCU would then only have to switch the base of a transistor to sink the current required for the relays at the right time (battery charged).

edited to add: Thinking about it, you probably don`t even need an MCU at all! if the relays have a set dropout voltage, you can simply set it such that when a battery needs charging it cannot supply sufficient power to a relay, the field collapses and automatically switches in the new battery 5086.contentimage_1.png

Your exact words describe a perpetual energy circuit, which cannot occur without getting energy from somewhere not mentioned.  Your exact words seem to say that you ruled out solar as the primary energy source for recharging what gets used by loads.  Was that really what you meant? 

It is possible to shuffle energy from one battery to another with a little bit of loss.  A tiny circuit which can move energy from a 1 to 2 volt supply such as one small battery to charge another 1 to 1.3 Volt battery is found in solar garden lights, to move power at 1 to 40mA from a 1 to 2 Volt solar cell to a small battery during daytime. Those also contain another power circuit to provide up to 10mA at 3V to a white LED while it is nighttime.

The circuits inside were globbed under epoxy, so I can't tell what was inside but I'll bet that they contain inductor(s), capacitors and a few transisters, possible similar to the Charge Theif circuit which got a writup online.

Those are much too small for serious power appliances but worth looking at if you are studying power management circuits.

Hi Uche,

I'm a master power electronics engineer and I specialize in DC-DC converters, solar charge converters, DC-AC Inverters, Power Supplies, and battery chargers. Yes, you can charge a battery from another battery, if that's what you're asking. I don't know why you need it isolated. However, I've got to agree with D2113F with reference to your other replies to this post. To me, it sounds like a perpetual motion machine wheras you have two batteries that are each connected to relays that can switch the individual batteries to either a load or to a a charging circuit fed by the other battery. Here is the problem. Battery-1 is connected to a load and is discharged to the point that you want to rechage it from the other battery that's been idle. Battery-2 recharges Battery-1 thru a dc-dc converter with a control to ensure that it's not overcharged. Now, Battery-2 is discharged and Battery-1 is charged, therefore, the relay or relays setup the circuit such that Battery-1 recharges Battery-2 and now Battery-1 is again discharged. Hopefully, you see where I'm going with this. It's an (almost) endless loop of the batteries charging and discharging each other. And if you powered a load first, discharging Battery-1, then recharged it with Battery-2, Battery-2 is now discharged and you can power the load only one more time with Battery-1. But now, you can no longer recharge Battery-1 with Battery-2 since Battery-2 is discharged, The only way around this is if you have some additional power from another Battery, or a Solar Cell, or from an AC-DC Power Supply to put the lost energy back into the system.

One of the first things you should have learned in physics is that there is no such thing as a perpetual motion machine. Since you used the energy in Battery-1 to power the load and the energy in Battery-2 to recharge Battery-1, and since you used-up the energy in Battery-1 again powering the load after the recharge, you are out of energy as both Battery-1 and Battery-2 are discharged. Does this make any sense to you? I hope so, but if not, please feel free to reply here or send me a message using the Element-14 internal messaging system.

Best regards,

Kamran Kazem

Meet the Tesla 4-battery switch. Ever tried it? http://www.greenoptimistic.com/2008/01/29/how-to-build-a-tesla-4-battery-switch/

Hi Ovidiu,

The article is very interesting.  I think what happens is that there is a slight time lag inside the battery from the time you begin loading the battery and to when it reaches a steady state.  By cycling the battery at higher frequency, you can get to the point where the electrical and chemical reactions reach a level of resonance, creating the short burst of extra electrons due to the chemical reaction collapse.

If anyone has one of these working, I would love to know how long you can run the circuit until you get either a chemical depletion or some other failure.

I really wish I understood electromagnetics as well as Tesla did.  The world truely lost a valuable resource when he died.

Just my opinion,

DAB

Hi

Thanks for your interesting contribution about the battery principle, I so much love your contribution to this article, I have been thinking in mind on developing a prototype simple battery and solar energy driven car, in this project I would like to perfect the energy source to be Kind of Forever energy supply, that is where I have this thought, My intention is to use two batteries one of the battery will start by powering an inverter of 12V to 230V AC, this inverter will as well power a dc 12v circuit that will be the motor control unite with PWM signal.

The circuit will have a dc voltage output source to isolation circuit with Opto-isolate components, I am thinking that the batteries will be charging well when the charging current will be independent from the source, and this is the reason why I would love to apply that technique.

I hope I am right with this ideal.

Regards