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Converted Audi A2 goes 605 km (378mi) without charging

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The US equivalent is probably the original Honda Insight.
honda-insight-6.jpg

Better highway mileage than a Prius. Aluminum chassis.
A bit of a favorite for long range EV conversions now.
I think it was a bit ahead of its' time as well.
 
Loads of details: Cost-effective EV battery passes German tests, recharges in minutes

The cost seems too good to be true.

This website has done a lot in terms of collecting information about DBM and trying to find out what is true and what isn't: pressw0rds

Although similar numbers for the estimated cost of a mass-produced battery are quoted from "Peter Hoffmann, The Hydrogen and Fuel Cell Letter", there seems to be no other verification for the numbers in the article above, and in general there are a lot of numbers where it seems completely unclear what they refer to. For example, some numbers refer to energy cost per year, with no explanation of what that means.

I'd certainly go with "too good to be true" for "$1,100 to $1,400". Except maybe if that refers to bare estimated mass-production cost divided by the lifespan of 10 years? Who knows. But if that ($14k) were the estimated cost for the 99 kWh battery, then a smaller version might fit the description (given elsewhere) of allowing to build a car at the "usual" cost. Plus it might be a low estimate. Pure guess-work on my part, sorry.

There seems to be much better support for the theory that the battery can be recharged in something like 10 min for 95%.
(According to a direct statement by Mirko Hannemann in this interview: Mirko Hannemann: “Alle Unterstellungen sind unberechtigt!â€￾ » CleanThinking.de)

The two battery packs we heard about, the one from the record-drive (99 kWh), and the one tested (63 kWh), are said to have quite different properties (pressw0rds claims that DBM press speaker Markus Röser has confirmed this):

Silberpfeil (DEKRA test):

62,928 kWh elektrische Arbeit
92 Zellen (180 Ah; 3,8V; 4kg) [46 packs à 2 Zellen]
368kg Gesamtgewicht
171 Wh/kg Energiedichte

Lekker Mobil (Berlin record drive):

98,8 kWh elektrische Arbeit
100 Zellen (260 Ah; 3,8V; 3,5kg)
350 kg Gesamtgewicht
282 Wh/kg Energiedichte

Gesamtgewicht = total weight, Energiedichte = energy density.

Nevertheless I have to admit I'm thinking about the possibility of whether the approximate weight of the first was erroneously used in the data sheet for the second, and so, whether it might be 171 Wh/kg for both. The number 171 Wh/kg appears to have better data behind it: Silberpfeil (aka Lekker Mobil II) pressw0rds
 
Would a 171 Wh/kg 98.9 kWh pack fit in the spare tire area of an A2? That would be a 578kg, 1274lb pack! I think the A2 might have it's front wheels off the ground. At 282 Wh/kg that's a 350kg, 770lb pack.
It seems as if the secret ingredient may be Vanadium
One of the most compelling break-throughs illustrating how Vanadium, when combined with lithium, creates “supercharged” batteries is the recent news by Germany’s DBM Energy. In partnership with German utility Lekker Energie, DBM Energy equipped an Audi A2 electric vehicle with its new lithium-Vanadium metal polymer battery and set a long distance record of 603 kilometres (375 miles) travelled on a single charge. The battery’s basic electro-chemistry consists of a metallic lithium anode and a Vanadium oxide cathode. DBM Energy claims the battery has 97% efficiency and can be charged at virtually any electrical socket. Plugged into a 240-volt direct-current source, the battery can be fully charged within 6 minutes.
http://www.energizerresources.com/index.php?option=com_content&view=article&id=421&Itemid=206
 
Would a 171 Wh/kg 98.9 kWh pack fit in the spare tire area of an A2? That would be a 578kg, 1274lb pack! I think the A2 might have it's front wheels off the ground. At 282 Wh/kg that's a 350kg, 770lb pack.
It seems as if the secret ingredient may be Vanadium

In one of the video interviews for which I posted links, MH was talking about additionally using the space below the back seat row. OTOH, in another written interview (which for it's over-precise numbers appears as if edited after being transcribed from audio), about 250 Wh/kg (as discovered since the previous message).

Personally, I decided to believe 171 Wh/kg, but consider everything else to be theoretical values, or unsafe prototypes, until independently proven otherwise.
 
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600 kW... 240V... 2500 Amps??? Not bloody likely! That kind of current requires solid copper bus bars at least 1.25 inches square. I can only imagine how big the cable would be!

From gm-volt.com article Cost-effective EV battery passes German tests, recharges in minutes
Updates in comment #71:

“Regarding the recharging time we use internal our own Power Bricks, an energy storage system, with 600 kW, Röser said.

Meaning, they claim to have been using 600 kW only from the Power Brick to the battery, which were probably next to each other. Don't know if that makes it more likely. I think somewhere else they were saying that they wouldn't know how to offer a charging system (as a product) for what the battery could do.

EDIT: However that probably helps for using it as a grid buffer/storage system.
 
It was all going so well until this
Plugged into a 240-volt direct-current source, the battery can be fully charged within 6 minutes
At what astronomical current?

If it's a DC source I don't see why they have to go with a standard voltage. Most likely it'll be something like 350-450V so it matches the charging voltage of the battery.

The 500kW charger for the Proterra bus uses huge bars and also a ESS as a buffer. Doesn't seem very practical for a car.

http://www.proterra.com/index.php/products/productDetail/C23/

For cars, I think 250kW is about the max practical fast charging power.
 
Personally, I decided to believe 171 Wh/kg, but consider everything else to be theoretical values, or unsafe prototypes, until independently proven otherwise.

With a 300 kg battery pack of 98 kWh we reach a distance of 600 kilometers without a stop and without a gas engine or range extender.”
http://gm-volt.com/2011/04/12/cost-...reportedly-passes-tests-recharges-in-minutes/
That's a pretty specific number from DBM and a lot closer to the 282 wh/kg number than 171 wh/kg.
 
http://gm-volt.com/2011/04/12/cost-...reportedly-passes-tests-recharges-in-minutes/
That's a pretty specific number from DBM and a lot closer to the 282 wh/kg number than 171 wh/kg.

Well, the problem is there are different specific numbers. 300kg would be 329 Wh/kg. The same person confirmed to pressw0rds that there are two packs with very different densities, which included the data here: http://www.lekker-mobil.com/images/stories/pdf/technische-Daten-Audi-A2.pdf. These are supposedly for the very same battery pack/car. Whereas the number 171 Wh/kg was calculated from a photo of labels on the batteries shown at the Hanover fair. If there are two battery types with very different energy densities, why don't they just clearly say so?
 
There seems to be a lot of lost in translation here...

Definitely. But even the original german are fragments of information which don't fit together neatly, so I don't feel like translating all that newly found avalanche of semi-information. But if you are interested in a specific question, I might get motivated to try to piece together the various bits related to that specific question. My guess is that DBM is more interested in teasing to get contacts, than in informing.
 
A person who claims to have done some investigating just posted over at DIY:
(energy density of the 100kWh car)
The so called lekker-mobile had a battery density of 282 kWh. The battery weight was about 350kg. Newer cars e.g. the silver-arrow (the one with which DBM passed the BAM and DEKRA tests) has an energy density of 171 kWh. Over all there seems to be at least 3 different versions of the battery (one other used in forklifts has around 140 kWh). But the exact energy density is one of the open questions...
http://www.diyelectriccar.com/forums/showpost.php?p=248507&postcount=109
 
A person who claims to have done some investigating just posted over at DIY:

http://www.diyelectriccar.com/forums/showpost.php?p=248507&postcount=109

The person is getting the information from the same blog which I have already referenced earlier, pressw0rds
It is not an independent "investigation".

I don't agree with blaming the "one" reporter for reporting that there was a time when he lost view of the record-making car. He was in a bus or van with other journalists, and the journalists were not driving themselves. For such an extraordinary record by an unknown company, that needs to be reported as caution. That this was blown out of proportion in many subsequent reports was mixed with a lot of wrong numbers, then called unbelievable, which didn't originate from him.
 
If it's a DC source I don't see why they have to go with a standard voltage. Most likely it'll be something like 350-450V so it matches the charging voltage of the battery.

The 500kW charger for the Proterra bus uses huge bars and also a ESS as a buffer. Doesn't seem very practical for a car.

http://www.proterra.com/index.php/products/productDetail/C23/

For cars, I think 250kW is about the max practical fast charging power.

It is probably a possibility that 240 V is just the input voltage of that power "brick", given how the spokesperson is using numbers without being clear about what they refer to, and that they indeed use a higher output voltage to reduce the current.
 
I believe pressw0rds is his blog, so it's his information that he gathered independently.

Ahh, possible, he says "don't want to advertise here" before referring to the blog.

What gave me a different impression was this item:

1. Lekker-Mobil (burned down due to an arson attack)

I think among all the information I was reading in the blog itself and in the references made there, was a indirect quote from MH that the car which burnt down wasn't even the record-making car itself (aside from the same battery not being in it). So the poster appeared to know less than what might be his/her own blog... :)

In any case, it is not information that can verify what what I already translated/quoted from that blog since a few days ago, except in so far as we might be reading/interpreting/translating the referenced articles and videos differently.
 
JRP3, I don't have a user account on that board (and am not going to build DIY EVs), but you might leave a message that we are discussing the blog over here. :)
Probably our thread here will eventually be found by the blog's author in any case. The pressw0rds blog is certainly the richest source of info and references I've seen so far about DBM.