TheEEStory.com

They will be configurable for any output voltage that optimizes vehicle performance, and will maintain that output voltage at a constant level over the span of each discharge cycle.

It IS a problem, but nothing compared to making the device itself work as advertised.

They can build these things to accept any volage necessary. doesnt have to be 3500v or even 5000v. it can be 4v or 12v. can be any size, shape etc.. just like any battery or capacitor.

This line interests me is because, as you know, Watkins monitors this board and he is aware of the issues brought up here, I believe.
One of the discussion we have relates to the down-conversion of the voltage all the way from 3500v, and keep it there when the voltage drop. This seems to directly address that question.
Of course it is a problem, as many people say that this could only be done by heavy AND expensive equipments. But LightEVs obviously says that: "This is done. No problems."

seslaprime wrote:

They can build these things to accept any volage necessary. doesnt have to be 3500v or even 5000v. it can be 4v or 12v. can be any size, shape etc.. just like any battery or capacitor.

If one does not have the 3500 volts, one does not have the energy claimed by the EESU.

It might be able to be stepped down, but the primary energy storage must be up there. Otherwise, its not different from the current supercapacitors

CapacitorMan wrote:

seslaprime wrote:

They can build these things to accept any volage necessary. doesnt have to be 3500v or even 5000v. it can be 4v or 12v. can be any size, shape etc.. just like any battery or capacitor.

If one does not have the 3500 volts, one does not have the energy claimed by the EESU.

It might be able to be stepped down, but the primary energy storage must be up there. Otherwise, its not different from the current supercapacitors

isnt 3500V the max capability? I was under the impression that they are not required to build these only to 3500V. just like chemical batteries have different voltages, capacitors have different voltages. this should be no different

A electric Bicycle is not going to carry a 3500V EESU. will it?

Last edited Mon, 20 Oct 2008, 12:24am by seslaprime

Selsaprime.

For heaven's sake, read any high-school physics textbook!

1. Capacitors work at any voltage up to a maximum.
2. The energy stored is proportional to the square of the voltage. if you drop from 3,500v to 350v you have only 1% of the energy in storage.

How can you assess whether these claims make sense without even the most basic knowledge of how capacitors work?

Perhaps a little more reading and a little less posting might be a good plan?

excoriator wrote:

Selsaprime.

For heaven's sake, read any high-school physics textbook!

1. Capacitors work at any voltage up to a maximum.
2. The energy stored is proportional to the square of the voltage. if you drop from 3,500v to 350v you have only 1% of the energy in storage.

How can you assess whether these claims make sense without even the most basic knowledge of how capacitors work?

Perhaps a little more reading and a little less posting might be a good plan?

Gee Wiz man, Calm down. sounds like that really pissed you off. I think maybe you been called a dumbshit way too often. as if you've never said anything stupid on here.

why read when I have such brilliant people like you to tell me why it will not work. maybe i'm just in way over my head here, all you PHD's and scientists.

so is this all you have to contribute to this topic?

Get a book on the subject and read a little. It is one thing to make a mistake - we all do that from time to time.

It is quite another to demonstrate that despite assuring us it works etc. etc. and babbling total nonsense about permittivity and the like, that you don't even know the most elementary principle of operation.

If you don't know what you are talking about, for heavens sake say nothing!

SETTLE DOWN NOW PEOPLE!!! We are all here to learn:-)!!

Well, it's about time some of us did a little homework before posting arrant nonsense.

For those that need to read it again

http://www.theeestory.com/topics/99

"how a capacitor works" thanks again Matt

I thought:
(a) eestor were not making the up/down converters
(b) LightEVs is a marketing company with no in-house design expertise

Other than promising everything to everyone as salesman like to do, what substance has this comment? And what additional size/weight will the conversion add to the envelope? Surely something serious customers need to know?

Of course, as exco says - at least this design job is doable (though maybe at size/weight that makes things much less attractive for two wheeled vehicles).

If LightEV is serious it will ahve to address these questions - and by more than just promises. As far as I know they have promised prototy[pes with all tehse qualities (and tehrefore including the up/down conversion).

Dream-on!

Tom

excoriator wrote:

Well, it's about time some of us did a little homework before posting arrant nonsense.

ROFLMAO ... now isn't that the pot calling the kettle black!

At least I know what a capacitor does. I doubt whether you or seslaprime has the faintest idea!

You are incapable of making a valid judgement on whether EESTOR can do what they claim or not.

excoriator wrote:

At least I know what a capacitor does. I doubt whether you or seslaprime has the faintest idea!

You are incapable of making a valid judgement on whether EESTOR can do what they claim or not.

Man I never seen anyone foam at the mouth so much over one little mistaken sentance. Boy you really have serious emotional issues. what are you, twelve?

I remember when you first came on here, you were so ignorant. sounds like you havent changed much at all.

well, enjoy it while you can. it is not often you get to jump all over someone legitimately.

Daniel R Plante wrote:

I believe the reference is to how the EESU looks like from an external point of view. If the application needs a "12 volt battery", the power electronics internal to the EESU will do the step-down to approximately 14-16 volts, and the control electronics for the bike will be designed as if they're interfacing to a 12 volt battery.

I've mentioned before that single dies (thumbnail sized slivers of silicon) for power switching applications already exist that will switch 4,500 volts at very high amperage.

For customers ordering lots of 100,000 or more, semi-fabs will typically re-design the die for your specific application. On-current specs that high are not required for that type of aplication, which would lower the doping level requirements in the conducting channel of an IGBT a great deal. This will greatly lower the cost and switching losses of the die (and therefore the cooling requirements). Large lot orders will lower the per-die cost significantly as well. Silicon Carbide-based dies are just becoming mainstream, and are proving to be very rugged in terms of voltage and heat handling capability - much more so than Silicon alone.

The external R&D requirements for integrating the EESU into a light EV should be no different for the bike engineers than for using a battery.

As for the power electronics internal to the EESU, this shouldn't require R&D, just D.