22 Replies Latest reply on Aug 12, 2014 2:24 AM by ronykhan

# How can I get a 10 to 12 volt capacity battery with two input and output

Dear Everyone in this community

Is it possible that a rechargeable battery may be it's more than one but two input and output port in that battery required.

Elaborate: A battery with input port which take and store electricity with higher than the second step to transfer the charge to other/himself continuously.

What if not possible then can you provide me the other solution wit same theme?

Regards

Rony

• Reply
• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Maybe you need some kind of buck or iso-buck regulator?

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

How can I get it and install it can I find ready made?

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Are you thinking of a Battery that can charge irself? If this is the case it is not practical. While you can charge one battery with another it never gives you as much power at your intended use as just using the two batteries to power the intended use (load). If I misunderstood you will have to give us a clear description of your idea and intended use.

A groups of battery cells can have several taps that allow you to take different voltages from the group. This is done rarely in electronics as it is more practical to take the full voltage and modify it in the circuit to produce the needed voltage levels.

John

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Dear John

Assume I use two rechargeable battery. one battery supply the power to a device and the second battery recharge from another power source. Now How can I transfer the power from second battery to first one?

Rony

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Hi Rony Electricity flows from a high potential level (voltage) to a lower potential level (voltage). Lets us assume the battery you are using on your device is 3.7 volts like most cell phone batteries and the other battery is 12 volts like in most cars. When we connect the cell phone battery using a circuit that controls the flow (charge rate) to the car battery so that the negative terminals are connected and the positive terminal are connected through the control circuit, electricity flows from the car battery backwards into the cell phone battery and it recharges. We do not want to connect the negative terminals and the positive terminals without the control circuit as it may cause the smaller battery to charge too quickly, overheat, and explode. The batteries used in cell phones are special and require special circuits to recharge properly. Now lets turn it around and say that we have a 12 volt car battery connected to our camping lights and we want to recharge it. We happen to have 15 NiMH AA batteries all charged up and hooked in series so that we have about 18 volts. Can we recharge the car battery with the AA batteries? Yes to an extent but practically no. We can hook the AA batteries up to the car battery+ to + and - to - and electrical current will begin to flow into the car battery. It will in fact begin to recharge but long before it has charged up much the AA batteries will start to go weak and as soon as their combined voltage drops to equal the voltage of the car battery the charging process will stop. When it comes to how much energy (electricity) a battery has we give it a rating of milli amp hours in the case of the AA and Amp hours in the case of the car battery. If you look on some batteries you may see how much energy they have fully charged listed. This means that the battery can supply this amount of energy. The car battery has much larger capacity than the AA. We can use a water analogy. If a bath tub full of water is equal to a charged car battery then a small cup of water is the AA battery. You can see how we can fill the small cup many times from the bath tub but if the bath tub is empty we can not fill (recharge) it with the cup. Transfer of energy from one place to another always costs us some energy. We loose energy in the form of heat when we charge a battery. Feel batteries that are under charge and you can feel the heat which is lost energy. Also there is no way to transfer all the energy from one battery into another. Some of the energy will be lost as heat and some will still remain in the battery supplying the charge after they have equal voltages. I hope this clears up your question a little.

John

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Dear John

I understand what you are saying. Now I make one thing clear like the cell phone battery is primary battery and it is like 3.5 v more or less So I need a secondary Battery like 7 volt. If the secondary battery can get 7 volt continuously then how can I make a series ? Think like this is just a part of a complete a series.  something like

Device⇐ Primary Battery⇐Secondary Battery⇐ Continuous 7 volt input

←  ←  ←  ← ←  ←  ←  ←  ←  ←  ←  ← ←  ←  ←  ←

So is it possible Mr. John? Think every battery(Primary, Secondary) need two port consume the charge(one port) and then supply(another port) at a same time.

Rony

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Hi Rony, If you hook two batteries together in series ( plus to minus) so that their voltages add up and then try to charge one portion of the battery using another portion you will only short out some of the cells. Self charging of a compount battery is not possible. The only way that one battery can charge another successfully is if it is higher voltage, larger capacity (amp-hour), and seperate.

You keep refering to multiple ports on a battery but there is only one positive terminal and one negative terminal. A rechargeable battery discharges and recharges through the same terminals. While a battery can only do one thing at a time it is possible to supply voltage to your device and supply a charging current to the device's battery at the same time. I often do this when I plug in my cell phone and talk on it at the same time. In this case the charger has enough power to run the device and still remains at a high enough voltage to cause electrons to flow backwards into the battery thus recharging it.

What you describe in your chain of batteries is possible. We could put a charger on a car battery and hook the car battery up to charge the battery of a cell phone and then run the cell phone at the same time but there is no real long term advantage to doing it this way. We would have a more efficient system if we just ignore the batteries and run the cell phone directly off the power of the car battery charger.

John

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Dear John

Would you like to make a design in short cut like I mentioned in previous chart/series & mentioned with the volt of two battery. like secondary battery charge the primary battery. I will be grateful to you.

Rony

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Hi Rony,  Sorry I still do not understand your question or application well enough to suggest anything specific. From what you have been describing my best advice would be to get two batteries that both work on your device and charge one while you use the other and then switch them around when you need to.

John

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Dear John

You don't need to be sorry. I am sorry that I can't make you understand. My thought is very complicate. I just try to find out that there is an easy way to make a series. Now I have to study rechargeable battery construction and find a way. I am a textile engineer. When I started to think something innovative to save time and energy. It was an electro-mechanical process to save the energy and time directly related to the cost to pre-treatment of yarn. then I have no laptop or computer. to design it. So some time I use one of my friends laptop Unfortunately I make a figure part by part and the working system of that project and also share with him. His elder brother is also a Textile engineer have passed from same university BUTex (Bangladesh university of textile) It's a government institute. Student apply 15 to 20 thousand they sort it by result of previous and only 170 seat in there. ok forget it.

My friend who stayed with me one day he left the apartment without telling me and show the project to her Elder brother. Now his elder brother is the younger richest person in textile. So I think you have already known. I will find a logic for my project. Whatever I asked you just one part out of six portion.

Thank you very much and sorry for wasting your valuable time.

Rony

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Hi Rony - I will try a different explanation. A battery is like a magnet. Just as the magnet can only have one N pole and one S pole. The battery can only have one unique Positive terminal and one unique negative terminal. If there are 2 or more physical places to make an attachment of wires these attachment places are really the same place as far as the battery is concerned. Whether you are charging or discharging a battery there are only 2 real connections.  Here is another analogy, think of the battery as a water pump. No matter how you hook up the pipes there is only one hole into the pump and one hole out of the pump. We can put Ys and Ts on the pipes but as far as the pump is concerned there is only one in and one out. Check out the link here to wikipaedia for battery.   http://en.wikipedia.org/wiki/Battery_(electricity) . Don't be afraid to ask more questions as you are not wasting anyone's time.

John

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Dear John

You are a nice person. you have many idea about electricity . Do you have any idea something like a circuit separate the volt. I mean in a wire there is 20 volt flow. Is there any device  or IC that can divide the voltage /power like 15v pass to the one line and 5 volt flow another line?

20 volt input to a device out put 15 Volt in one line and below 5 volt

————⇒Ο————⇒

⇓5 volt

⇓

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

The volts don't flow the current or amps flow. Think of volts as pressure and amps as the quantity of electrons . We can divide voltage up in many was but here are a couple of the most common. The resistor values in the resistor divider are for illustration only. They would have to be adjusted to work with what ever you are powering with the circuit. The Voltage regulator will automaticly, within their design parameters, adjust to accomodate a changing load. I have reposted the drawing as the first one was not clear and while this one still isn't clear it is better. If either one interest you I will draw one on CAD and make it clearer.

John

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Dear John

I insert a image. I have a very little knowledge about electrical and electronics. So In that image is it possible?

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Hi Rony, No this is not possible without including the load resistances. This is like connecting a large diameter hose and a small diameter hose up to the same water source and expecting a different static pressure at the end of each hose. In your drawing you would measure 20 volts at all points. You would have to do it in a manner similiar to how I drew it.

John

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Dear John

Is it possible to find a way to split 20 volt to 15 volt and 5 volt? There is no energy loss by adding resistance.

Rony

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Hi Rony - It is difficult to give you a specific answer as I do not know what you are trying to do. As you have seen in my drawings it is possible to split 20V into 5V and 15V. However there is always energy lost. It is lost in resistors if they are involved and it is lost in the internal resistances that are inherent in every electrical component in the real world. I believe you mentioned that you have an education in textile science? You are asking me questions that are similiar to, Can a thread be used for the warp and the weft at the same time? Can a thread be pulled through a machine without friction? If you want to give me more information you can contact me directly without sharing your idea with everyone.

John

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Dear My Friend John

You ask me a question the answer you have already known. From the very beginning of humane race there are everything is universal truth. Now human make the impossible to possible. I don't know that you know the prophecy of Christian, Muslim, Jews about the false messiah? My question is not to offence you. I have a little knowledge about applied physics though I am studying from the beginning. I just ask you a question that is it possible or not for now? By the way I am textile Engineer. Textile science is another part. Textile engineer utilize the invention of textile science and ask for the modification. Engineer work in a field and their tool is invention of science. You ask me about the function of weaving like warp thread and weft thread used at the similar time? If your main task is manufacturing the fabric you can use knitting process where two thread make a loop and cross one over another at the same time. If it's delay then the knitting fault occur. I just wanted to know similar thing the alternative idea, is exist or not? What if not then I have to think another way or method. God give us the nature to utilize it.

Rony

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Could you be looking for a transfer switch?

Marine: Battery Selector Switches

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

You are correct, John, good explication as well.  My curiosity is piqued, however.  It would be silly, but I think one could construct a battery of electrochemical cells that had two different anode materials.  Then it could be rechargeable and source two different potentials.  The chemistry would probably be a nightmare.

In real life we achieve this functionality if different ways.  Generally, we would use a SMPS to generate the different potentials.

• ###### Re: How can I get a 10 to 12 volt capacity battery with two input and output

Don, That is an excellent insight and would make an interesting battery with actually 3 different potentials from one cell. Now all we have to do is dream up a relevant application.

John