Battery question and motor response

i have alot of questions about making an EV conversion but first need some help.

Can you use both 6 volt and 12 volt batteries on seperate packs on one motor by using the 6 volt batteries for low speeds 0-40 and then the 12 volts for 40-80mph speeds? and if you did this right would it break or hurt the electric motor?

Well the motor could care less the chage of voltage/batteries, it would be the controller that is gonna care. Now i want to ask, what are your intentions in using a hybrid pack system? it does not seem effective…

its far fetched but if i use to batteries i would like to charge one for the motor than use wind energy in the for of electris generator to charge the other set while i drive than switch them over and have the motor run on the newly charged set and have the use set start chargeing. i know its crazy but i want to see what efferctivness it would have. any thoughts

i wouldn’t do it only because it would be a pain in the butt recharging the system. you would need 2 different rechargers to recharge the volt specific batteries

That would not work at all. I am sorry to shot you down but the physics would not permit it. The amount of air resistnace from the wind prop would take away more energy form the traction battery. IN other words any electricity that the wind turbine makes would be less than the extra energy needed to combate the wind resistance. You would be loosing energy due to the system not being 100% efficiant.

have you or anyone ever actually proved this to be true ? i want to see it in action before i just agree and give up, you can understand.

i cant agree with that…


Try it and let us know how is goes… I stand firm by my statement.

[QUOTE=FEUS;935]i cant agree with that…

Energy can’t be generated. It can be released from sources such as gasoline, stored energy in the battery or nuclear engery in the atom etc. Since you are converting stored energy in the battery to kinetic energy by moving the car, if you try to take the wind drag and put it back to your battery the net effect will not be to give you extra energy (because energy can’t be generated). In fact, you will loose energy by dissipating in various forms such as heat and sound etc. That is why no one has built a perpetual machine.

This car will solve all our problems! look at it go! yaaay! :slight_smile:

…seriously, is this video a joke or are people really that dumb?
things like that can only work if the car is stationary in a windy area, or if there happens to be alot of wind contrary to the driving direction…

Oh, the batteries will charge. But most generators are under 90% efficient. Then a converter from generator voltage to battery pack voltage you’ll lose another 5-10 percent. Mechanical losses (transfering wind to rotational torque) is another 5-10 percent. Now, the charge capacity of a battery, you lose another few percent. Now you have yourself losing at least 25-30 percent. So thats 70% efficient, and thats IDEAL.

What do you think the effective KWH generating capacity of that system is? Multiply that by 70% and Compare that to what the vehicle needs to drive WITH the extra drag? I bet you its almost negligable.

It will charge the batteries, but I doubt you’ll get more than an amp out of a wind generator even if its the most efficient one you can get. You MIGHT get an extra 1/4 mile, but not enough to matter, especially when you’re using hundreds of amps.

If its such a good idea, why isn’t everyone doing it? Because its NOT lossless. Its a LOSSY system. The drag from the propeller/fan assembly is enough to KEEP you from going an extra 1/4 mile.

Physically its not possible. Wind resistance will likely take away any and all gain you would get from the wind powered generator. Its not like you’re going to be pushing amps and amps, its likely only a couple, if that.

Do this for us:
Find a generator that can output the amperage you need (10-20A)
Tell me how bit that generator is
Tell me how much torque it takes to get the rotor moving from a stop to full RPM to produce max amps.
Tell me how large of a fan you need to create that torque on the rotor
calculate the wind resistance of the generator/propeller assembly

Then you calculate Drag
Then you calculate how fast you need to go to produce enough current to charge the batteries. (I bet its quite a bit)
Then you calculate the drag of the bike to see what it needs to be pushed to that speed
Then add the weight and drag of the generator/prop to see what it needs at that speed
Compare the two, subtract, thats the extra capacity you need from the batteries to push along the extra weight and drag.

Then calculate the current you CAN generate, and how much current you NEED and I bet you get a negative number. I bet you’ll find out, that physics rules, and has shot many people down with this same idea.

So if you want to argue some more, go ahead, PROVE IT! You prove it physically and let me know what you find. In fact, I’ll have it published in every technical, engineering and physics magazine out there.

Oh, and I’ve got a bridge to sell you too…