What the hell have i just walked into
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Okay, so the first capacity test is finished and I’ll post the discharge curve later today. I did discover that the 3.45V cell voltage that I used for the cut-off voltage (41,4V for 12S pack) is actually way above the practical cut-off voltage, but I was confused by two different voltage values found in the datasheet.
First of all the general summary information on the cell says 2,7V-4,15V
But then there’s this OCV charge and discharge chart, but I don’t understand for what reason they only discharge down to ~3,40V… a quick google search tells that OCV stand for open-circuit voltage (no-load/resting voltage), so does this graph actually tell what the resting voltage is at different stages of SoC.
Looking closer at the testing method it looks like the discharge current is 1/3C, which for a 94Ah cell (datasheet is for the 94Ah cell) is ~31A, so I wouldn’t actually be that surprised if the voltage did rise quite a lot at the low end, but I’m a bit annoyed that they don’t specifically tell what their cut-off discharge voltage was.
Then there is the an actual capacity test chart also in which they do discharge down to 2.8V, which is quite a bit lower than the 3.45V than what I did for this first run and got quite a bit lower capacity rating therefore.
So I’ll graph the first test and post the results and start charging the pack back up for a second test.
EDIT: here’s some videos for the i3-pack for the time
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So, first capacity test results: 103Ah, 4,6kWh. Test current 3,2Amps, 15min/5min (ON/OFF), stop at 41,4V pack (3,45V cell)
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Was that you involved in the three man looooong distance ride with trailers awhile back?
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Could it be discharged down to 2.7 rest for 24h then check the resting voltage with every thing disconnected voltages can increas and with the heavy drop off at 3.4v it’s possible the cells could bonce back that high
Car packs probably dont cycle 100% like we do in our boards to increase the life span of the battery.
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Agreed.
The depth-of-discharge, charge voltage, and temperature ranges are very limited for EV packs to help increase the cycle life. People would definitely get pretty pissed at replacing a $15,000 pack every year. 
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Going for another capacity test, now going down to 38,4V (3,2V cell)
Reporting on this in a few days.
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Second discharge was much closer to the 5,3kWh, still not quite there, but close enough.
Given that I don’t know exactly what kind and how long this module was used in an i3, I’d say this is a pretty good result. It’s clearly visible in the discharge curve that the battery is hitting the much steeper end of the curve at the end, so there isn’t that much energy left in it anyway.
I hooked up the big meanwell LED driver and charged the battery back up at ~9.8Amps average current. There was actually quite a big difference at the bottom end of SoC in the cell voltages (sorry, no pictures), they are perfectly balanced at the top, but had like 100mV difference between a couple cells at the bottom.
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Hey that’s impressive and overwhelming (just the fact that you’ll go after Arctic with your board is insanity), wish you full success with the project!
Are you keeping your current wheels etc? Or planning upgrade to big fat tyres for the deep snow?
Also about ESC, will you be bringing spares or would you consider using something higher end like a pair of Phaserunners fully waterproof?
Got me lot of questions on how your setup will hold on 
Also how do you plan your charging? Is the plan to bring as many Wh as possible and go do the trip on a single charge ?
I’m also curious about what spare parts and tools you’ll be packing
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now thats just impractical
What is?
Even in summer there is still snow ? Are the road deiced ? If not that would be a no-go for me
I’m gonna go into the arctic circle, not the arctic per say, but if you look at the map below I have marked where the arctic circle begins and where my start and destination points are.
There is no plans for snow encounter on this trip. At least in any major way.
Not doable with any kind of reasonable setup in one charge. I believe I can get around 300km in one charge if I go full 100% - 0% DoD, but I will be charging along the way where I can. It’s gonna be roughly at least 2200km, but I have a thread about this plan here
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I was indeed under the assumption that there was snow on your journey (and thought you were taking your board to the Arctic) 
Any chance to hack a car charging stations network?
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He needs a 220v capable charger, which Im sure he does since he’s in Europe
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I have actually already built a J1772 to a normal european AC outlet adapter and the 480W meanwell LED driver is an international AC/DC PSU so it can be plugged into 100-240VAC 50/60Hz. So I believe I will be taking the adapter with me so if I want to, I can use a car charging spot on the trip.
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