[Yabert]

Hi all

By interest and because I'm tired of don't know the real performance capability of the Volt battery, I've decided to test the power of the Volt battery pack.
Of course, I don't have powerful/accurate/costly test equipments, but I have a 125 Kw electric Smart Fortwo

So, the plan is to disconnect my current battery pack and drive my car with 1/4 of the Volt battery pack (24S for 90v and 45Ah, 84 lbs battery). I will set the Soliton 1 at 450 battery Amps (10C), record the acceleration and if the result is promising, try at 675 battery Amps (15C).
Tesseract has repeat many times that the Soliton isn't a laboratory module, but a fairly accurate result is still better than nothing.
After, I will be able to confirm than the Volt battery will be able to provide 4 times the peak power I've found at 15C.

If you have other tips and suggestion, let me know.

Oh! And let me few days to do the test... I still charge the pack with my 8S 300w charger tonight

 

[Moltenmetal]

Yabert, you're awesome. Let us know what you discover! That pack, when you can get it, is the cheapest Ah of reasonable weight that you can buy. The more the DIY community can learn about it, the better!

 

[Yabert]

You are right Molten and I think than absolutely no exemplar of this awesome battery should finish his life at the scrapyard… So take the phone and call all the scrap yards to avoid an unjustified end at those batteries.

I would like to have tips about how create a nice graph with the numbers record by the Soliton.
Is Excel sheet work well or there is a nice program for it?
Thanks

 

[piotrsko]

Are you still water cooled? How modified is your pack? I've gutted the control electronics and can get 7C with no ill effects so far but I use a coolant.

 

[Yabert]

So... this battery is awesome with a potential of over 230 kw of peak power at 15C discharge

The procedure used: Recharge at 4.15v per cell, temperature around 25°C, flat terrain acceleration for few seconds without using water cooling.
I've start with a discharge at 10C (450A), continue with a discharge at 15C (675A), followed by another discharge at 15C.

Enjoy the data!

 

[Yabert]

I've add pics to give a scale at what has propelled my Smart during those tests.
Also, consider the fact I use poor conductivity 8 Awg wire for my test... What I've on hand
Around 4 feets of 3x8Awg (multi conductor wire) for the positive loop and around 4 feets of 1/0 Awg for the negative loop.

 

[Yabert]

Is that I'm the only one to be very excited to discover that this 2K$ battery can potentially* give 285 Kw of power at 20C?

*3v difference between 450A and 675A imply an internal resistance of 0,56 mohm per cell.
So, at 900A the voltage drop should be less than 15% for a peak power capability around 280-290 Kw

...absolutely no exemplar of this awesome battery should finish his life at the scrapyard…

Today, at least six 2011 to 2013 Volt battery available in USA scrapyard: http://car-part.com/
Please save their lives... and you money... and the planet (reused waste)

 

[kerrymann]

So... this battery is awesome with a potential of over 230 kw of peak power at 15C discharge

The procedure used: Recharge at 4.15v per cell, temperature around 25°C, flat terrain acceleration for few seconds without using water cooling.
I've start with a discharge at 10C (450A), continue with a discharge at 15C (675A), followed by another discharge at 15C.

Enjoy the data!

Awesome. I love data! Especially volt battery data. Did you measure the temperature during the pulls?

Are you planning on keeping the liquid cooling?

Nice work!

 

[piotrsko]

Is that I'm the only one to be very excited to discover that this 2K$ battery can potentially* give 285 Kw of power at


Today, at least six 2011 to 2013 Volt battery available in USA scrapyard: http://car-part.com/
Please save their lives... and you money... and the planet (reused waste)

No, there will be lots of excitement, but right now there isn't a lot of available hard back-up data and there IS lots of conjective superfluous opinions of any naysayers. I had a hard time getting physical limits, not to mention data on the control electronics. Can't believe nobody has useful hacks after 3 to 8 years ( depending on model of volt)

The wrecking yard is another minor issue. Most do not understand what they have and are terribly afraid of the battery, once again due to the hyperbole from the media. My wrecker handled the pack like an explosive device.

 

[Tesseract]

... Most do not understand what they have and are terribly afraid of the battery, once again due to the hyperbole from the media. My wrecker handled the pack like an explosive device.

Not unreasonable, as the complete pack (~360V * 45Ah) has the energy content of ~14kg of TNT. Or ~58 sticks of dynamite, if you prefer...

 

[jddcircuit]

Is that I'm the only one to be very excited to discover that this 2K$ battery can potentially* give 285 Kw of power at 20C?

You are not the only one excited. I am right there with you.

Jeff

 

[Doctorbass]

Very interesting test Yan!!

The only thing nobody ever tested on the web is SHORTING one of these 400V EV battery !!!

We want a plasma event !! on youtube !!

Doc

 

[Karter2]

Doc, do you have any more info, ( source, cost etc ) for those Tesla packs/modules that you posted over on ES?
It will be interesting to compare data with these Volt packs.
K2.

 

[Yabert]

Are you planning on keeping the liquid cooling?

I don't know! Really, I don't have enough place in the Smart to allow the extra space requirement for the water hoses and the test I've done give me good idea that this battery will not overheat by powering a Smart at 10-15 Kw continuous.

But on the other hand, I don't know the best temperature operation for this battery... between 10 and 30°C? 20 and 40°C? Less, more???
Air heating in winter isn't a problem for me at this moment...



Hi Tess, while you are here, can you say me what is my 0-37 mph time? I've never understand the time scale of the Soliton program.
Thanks

 

[piotrsko]

Tons of rumors on the internet saying the battery capacity is reduced by XX% over 120°F. Just lousy amounts of verifiable hard data, or I am incapable of creating a good Google search string.

 

[Tesseract]

The Soliton reports time in milliseconds, so divide by 1000. The interval is usually 10ms, but if the overworked little AVR inside is particularly busy it might miss a logging interval.

I can't quote your post for some reason. The same thing happened to one of my posts a couple weeks ago.

 

[Yabert]

Super! That mean 5.5s for 0-60 Km/h (0-37 mph) with a 1900 lbs car powered by a 84 lbs battery

 

[piotrsko]

BTW: doing the math gives me 18 KWh. 4.2 v x 45 ah reported x 96 cells. However useable seems to be 5 kWh? My low cutoff might be too high.

 

[Yabert]

math gives me 18 KWh. 4.2 v x 45 ah reported x 96 cells.

4.2v is the fully charge voltage of a cell. Nominal voltage is 3.75v (360v nominal and 45Ah = 16 Kwh).
What is your cut of voltage? I think between 3.3v and 3.4v per cell should be good.

 

[piotrsko]

Hard cutoff is 3.0. Waste BATTERIES to absolutely get home is 2.75. Usually end at 3.5. Arrived from wrecker at 3.3