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Big difference between the Roadster batteries and the Model S batteries. Roadster batteries were Cobalt Oxide, which is very volatile and has very poor cycle life. The NCA cells that the Model S uses are vastly improved. They aren't quite as safe as LiFePO4, but they are close. And if you stay away from the SOC edges, they will last for ages. Again, not quite like LiFePO4, but close.

I wouldn't use them without BMS (I wouldn't use anything without BMS) but it's not the death sentence that it is with Cobalt Oxide.
 

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Discussion Starter · #42 ·
Didn't know that they did that for the Model S. It makes sense that they would though, as the lithium cobalt oxide cells can be very temperamental.

I'm going to be working on my GT6 again in 2 more days and we will once again get to spend some quality time together. Maybe I'll get a chance to do some testing, but that will be quite difficult without a valid drivers license(long story).
 

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To clarify: I think you meant to say that a BMS with a top balance shunt charging circuit may shorten the life of CALB cells- I agree with you on that in relation to any Li-ion cell, based on my admittedly limited knowledge of the cell chemistry, and I do not shunt charge my Sinopoly cells for that reason. There's no way I'm aware of that having nothing more than a LVC and HVC alarm trip on each cell could harm the cells, other than during a very, very long storage event between charges so that the parasitic losses from the BMS alarm trips actually drains cells below LVC.
 

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Discussion Starter · #44 ·
I got to drive it today. It will need a bit of work before its legal, but it's getting closer.

To clarify: I think you meant to say that a BMS with a top balance shunt charging circuit may shorten the life of CALB cells-
That is what I meant.

I agree with you on that in relation to any Li-ion cell, based on my admittedly limited knowledge of the cell chemistry, and I do not shunt charge my Sinopoly cells for that reason. There's no way I'm aware of that having nothing more than a LVC and HVC alarm trip on each cell could harm the cells, other than during a very, very long storage event between charges so that the parasitic losses from the BMS alarm trips actually drains cells below LVC.
My LVC is set by the motor controller already.
 

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Discussion Starter · #46 ·
I am trying to get my Brusa NLG513 charger to connect to my computer. I won't get around to balancing all of my cells before I leave in a few days, but I might just get the charger ready for my 192V pack.

This car's acceleration is scary, and can easily go sideways when I step on it. I don't want to abuse it too much though, as my batteries are not balanced and do not have a full charge. The good news is that there was no measurable voltage drop on any of the cells in the months that the car say. None. Not even 1/1000th of a volt.

I will be coming back to work on it again in December.

Once I am back in Texas, I will resume progress on that home-built electric-assist recumbent velomobile.

http://www.diyelectriccar.com/forums/showthread.php/prototype-anarchotrike-156665.html
 

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Discussion Starter · #47 ·
I got a 1-week extension of my vacation.

The BRUSA now works. I didn't know how the AMPSEAL connector worked and didn't have the pins inserted properly. My computer was communicating with unconnected wires.

Since Jack Rickard showed me how it worked and put the connector together properly for me, I was able to get the charger programmed from his old Toshiba labtop. I felt rather stupid for not realizing that there was no data transfer going on at all at my home PC, the way I had configured the connector, but at least the problem is now solved.

I bought an extra 5 batteries as well. This will give me a 208V 100AH pack. Tomorrow I will start the tedious process of bottom-balancing all of the cells with the Powerlab 8 I had purchased, then giving them their first full charge with the BRUSA when they are ready.

The Soliton is soon going to be re-programmed for the following:

Max Battery Current: 600A
Max Motor Current: 680A
Max Motor voltage: 180V
Max Power: 100 kW
Current Ramp Function: 680A/sec

Theoretically, with the extra voltage, a top speed of ~150 mph once my aeromods are installed and I put some 14" rims and larger diameter Z-rated LRR tires to make the overall drive ratios taller.

In practice, it has not exceeded maybe 40 mph yet, and probably won't anytime soon.

It smokes its tires quite effortlessly from a stop, even without the full 1000A used.
 

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Discussion Starter · #49 ·
I went to St. Louis a month ago, but didn't get as much done as I had hoped. I wanted to get a paint job done, but didn't get that far.

Here's some pics from a month ago:







 

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Discussion Starter · #50 · (Edited)
These pics are two years old and I've been meaning to post them here but kept getting distracted by other priorities. Anyhow, here are some pics of it primed up:








I'm currently back home and looking for employment again so that I have money to finish it.
 

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Discussion Starter · #52 ·
Hello zombie thread :D

No matter all the crap life throws at me that gets in the way, I won't give up on this project. Had someone handed me a pile of money when I was in high school, the possibility exists that I could have made a conversion with range as good or better than the OEMs.


I first drew schematics for this conversion when I was 17 years old and it was initially intended to use AGMs...


I'm now twice as old, but at least it's about 80% complete now...


If I ever find a well paying job again, a Tesla drivetrain/cells could be in this car's medium to long term future.
 

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Discussion Starter · #54 ·
Always admired your persistence. Tesla components would be awesome, once a few hundred thousand Model 3's are on the road parts should get pretty cheap.

With what Tesla has, I think a base level Model 3 drive system and battery could be fit in that would allow a sub 2000 lb vehicle weight. So, theoretically 300+ miles range at 60 mph and 0-60 mph in under 4 seconds with a top speed exceeding 200 mph(not that I'd want to try it without some serious and expensive modifications that would be needed to do it safely) and requiring no transmission.


No plans for that at the moment though. I still need to finish it as it is, and be very careful where I operate it because I have no license.
 
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