Alternating battery banks for increased range.

[JasonG]

While this would be easiest to test in a HV hybrid, the EVs would benefit more.

Here's the concept:
Lead batteries benifit from resting between discharge cycles. The studies I have found show diminishing returs past 15 min.

If you had 2 banks of batteries and alternated them every 5 or 10 min, would it increase the range due to the packs recovering ?

Any body with an Insight or Prius with a spare battery pack that would be willing to test this ?

A parrallel set of batteries in an EV would be the best, but most people don't setup that way.

[Ryland]

I think you would get better results if you used both packs at the same time because otherwise it's going to be like having two people on a tandem bicycle but they take turns pedaling, if they both work together they share the load/work and are not stressed as much, look at the battery specs, they give an amp hour rating for different discharge rates, discharge faster and you get less and the batteries over all life is shorter as well.

[Daox]

Ditto. The peukert effect is huge and negating it as much as possible is always a good idea.

[byte312]

Not a bad thought but, the more weight you put in the less the range. Putting more batteries in a car adds more weight. I think the solution is the correct battery and nothing more than what is required to power the motor at peak tourque. Just stop for lunch and rest the batteries. Effeciency is the inverse measurment of waste. If your motor weighs 150 lbs and is 80% effecient it wastes more than 20% of the energy available. If your motor weighs 50 lbs and is 80% effecient it will waste less than the first one but still more than 20%. This is because the motor must pull it's own weight. If you find a way to capture some of the waste energy and use it, you will come out ahead.
The Tesla switch was a circuit that always charged one battery through a motor with two batteries supplying a higher voltage in series. After a short time, the batteries were switched with vacume tubes so that two batteries always charged a third one. The energy was pasted back and forth through the motor. It worked but it required an extra battery which sometimes burst into flames.
I have built a cuircuit that works on the same principle but it uses air-core transformers and capacitors to store excess forward current, reverse EMF, and noise from the motor. Once stored in the capacitors, the waste energy is avalable to be used for any usefull purpose.
The power to weight ratio is important. always check your batteries and motors for the best ratio. For a battery, divide the watt hours (amp hour x volts) by the weight in lbs. The larger the number the better as this is the power per pound. For a motor. divide the horsepower or tourqe by weight.
I give away the schematics free to anyone who asks for them. I can send PDF files packed with info.

[Ryland]

Originally Posted by byte312

The Tesla switch was a circuit that always charged one battery through a motor with two batteries supplying a higher voltage in series. After a short time, the batteries were switched with vacume tubes so that two batteries always charged a third one. The energy was pasted back and forth through the motor. It worked but it required an extra battery which sometimes burst into flames.

What is your source for this? Because this does not work without ending up with a net loss so why even bother? you can not create energy and batteries just store energy.
Also if a motor is 80% efficient it doesn't matter if it's 150 pounds or 5 pounds it's still 80% efficient.

[dcb]

tesla switch = smuggling in an overunity discussion.

[NeilBlanchard]

The folks at ChargeCar.org are pretty sure that using a supercapacitor in conjunction with lead acid batteries can make a huge improvement in stress on the batteries. The supercapacitor is just ~1/500 the capacity of the batteries, but it can cut the high current I/O to the batteries and therefore cut the heat gain by at least 50%.

[byte312]

Originally Posted by Ryland

What is your source for this? Because this does not work without ending up with a net loss so why even bother? you can not create energy and batteries just store energy.
Also if a motor is 80% efficient it doesn't matter if it's 150 pounds or 5 pounds it's still 80% efficient.

Look up Nicola Tesla on the net and you will find many wonders including the Tesla Switch, the Tesla coil, the first AC generator, etc.
I am afraid that what you do not understand is that if a motor is 80% efficient it was given that rateing sitting on a test bench and running at a specific load and speed and the weight was not an issue. In a car the motor weight changes the numbers because the motor must pull its own weight. a 5 pound motor rated at 80% would run much more effeciently under its own weight than a 150 pound motor could. This is assuming that the horse power rating was the same for both motors. If you and a friend were to run a race and you had 1000 lbs on your back but he carried no extra weight, who would win?

You can't create energy but you can save it. It is a matter of reclaiming waste. If money falls out of your pocket you can just walk away or you can pick it up and spend it without violating any of the laws of phisics.
The range of the car depends on our using every last watt.

[Frank Lee]

Depends. If you have a Ranger or S10 EV conversion and you put a 100 lbs lighter motor in, there will be a savings but in a vehicle of such overall weight it won't be much... certainly not a deal-breaker for the heavy motor.

[byte312]

Originally Posted by dcb

tesla switch = smuggling in an overunity discussion.

No not really. If you hand me a dollar and I give you back 80 cents, that is 80% effecient and what a fabulous deal! Would you be happy? Now if you demand at least part of the 20 cents that I took away, you would be getting closer to 100%. Overunity would be if I gave you one dollar and ten cents back for your dollar. That is just not possible and I would never attempt that.