Any final results to share? Have you tried to find an actual top speed or is 80 it?

Great build and great read!

 

Any final results to share? Have you tried to find an actual top speed or is 80 it?

Great build and great read!

Wow! This thread feels like ancient history now . Time goes fast in EV world.

I just passed 5000 EV miles, car is running great. We had a record cold spell here in Tampa, with temps below freezing all night long, so my battery performance was lower than I expected and I found couple of weak cells which get even weaker at cold temps, but everything is still working OK as long as I don't floor it in the morning. I have my new MiniBMS installed and its proven to be useful during cold days, LVC kicks in on weakest cell under heavy load and HVC stops the charger a little sooner than usual due to faster voltage rise on weak cell during cold temp. This helps prolong the life of the weak cells until I get them replaced.

As for top speed, I had it up to 90 mph a few times. This car could hardly get to 90mph even with ICE, so its not bad at all. I can keep up with freeway traffic easily and I pass people on local roads all the time, usually driving 50-60 mph around town, I live in somewhat rural area

I could use a little more acceleration sometimes, but I had to pull back max battery current on Soliton1, since it can suck the life out of my battery, especially when my lead foot wife drives it

If I was to do it again, I would use 200AH cells and get extra 5 cells or so, but back when I bought my cells they didn't have 200AH in small pkg they have now and I couldn't afford extra cells.

Hope this helps.

 

What do you have your Soliton1 set to? Like battery AMPs, motor AMPs, battery volts, etc.

 

I only limited battery amps to 450Amps, and set appropriate low voltage level for my pack which is 108V. Everything else is default, so motor amps can go up to 1000Amps, but due to my relatively low voltage pack and battery limiting motor current doesn't usually get over 800 Amps during acceleration.

Most of the time I drive at 50-60 mph and draw about 150 Amps, which is under 1C for my pack. But heavy acceleration can easily pull 450Amps from the pack for as long as I keep it floored until I get to cruising speed.

Oh , I also recently put on new tires, those GoodYear Fuel Max which supposed to be like 5% more fuel efficient. I can't tell if my range is improved, but tires are really nice and quiet and handle real good. They get great reviews and I can certainly recommend them, they aren't very expensive either.

 

Hi Dimitri.

Could you tell us a little more about the problems you're having with the TS cells? How did you noticed that some cells are worse than others?

Thanks.

 

Hi Dimitri.

Could you tell us a little more about the problems you're having with the TS cells? How did you noticed that some cells are worse than others?

Thanks.

We had unusually cold winter in Florida this year so at first I noticed significantly deeper voltage sag on some cells. They would dip to 2.5V at 3C even at full charge. This was at around 60F ( 15C ) cell temperature.

Also, even at warmer days those cells would sag deeper than the rest at 3C, but at 1C-2C their differences aren't as obvious.

I rarely go over 30 miles a day and last year I had proven 60 miles range with my pack, but now those weak cells limit my range to about 40 miles.

Those cells are all from a different production batch and have lower capacity than others, 160AH vs most of my cells at 175AH ( all were sold as nominal 160AH, but most cells from a newer production date had higher factory tested capacity ).

When I planned my pack I foolishly believed TS claims of 3C continuous rates, so over the past year I often pulled 450-500 Amps from the pack, sometimes up to 30 seconds at a time, and few times during Soliton1 testing I pulled those amps for 1-2 minutes at a time. Since few of my cells were 160AH and the rest are 175AH, that means smaller cells were exposed to 3C rates, but others were less than 3C, about 2.7C.
I think this was the key why those smaller cells got weaker and lost some of their capacity and got higher IR now, while larger cells haven't gotten so bad.

All this tells me that TS cells should not be subjected to 3C rates despite what TS claims. I think 2C-2.5C acceleration and 1C or less cruising is the best these cells can do.

I am even more concerned about lifecycle of TS cells which are oftent used at high C rates, since published lifecycle data is for 0.5C and its most likely lower for higher C rates, but we don't know how much lower since there is not enough historical data to go by.

Based on all I learned from my past year I now limited my Soliton1 battery current to 400Amps, which limits my acceleration a little, but its still comparable with most cars on the road and I can still pass people, but not as easily as before . I also ordered a test sample of 4 200AH new HiPower cells, which claim much better performance than TS. I will parallel my weak cells in pairs so they can still work and will add HiPower cells in series to my pack to get total of 41 series cells with various capacities Hopefully this will improve my peformance a little and prolong the pack life. It will also give me a chance to compare TS and HP cells side by side. I will publish the data once I have it.

 

I thought Hipower claimed the same specs as TS?

 

Yes, their claims are very similar, but I already know that TS's claims are damn lies, so now I will see how truthful HP claims are. At least this time I did not spend 11K and I got 200AH cells, so I won't be running 3C anymore. When analysing results I will have to adjust C rates depending on which cells I am looking at, so we can get better "apples to apples" picture. I won't be able to get HP cells to 3C rate since that would kill my TS cells, but I will get close to 2.5C , so we should see how they compare to TS 2.5C rate.

 

10,000 miles update.

Funny, there isn't much to say after 10,000 electric miles. The car drives just like day one. I'll try to recall what I have done in the past few months:

- while initially playing with raw power of Soliton1 I slightly damaged 5 of my TS160 cells by subjecting them to 3C currents for 15-20 minutes straight, doing test runs. Perhaps these cells weren't perfect to begin with, they are all from an older batch, based on manufacturing date and serial numbers. This was prior to development of MiniBMS, which would have certainly saved these cells from damage, by preventing low voltage sags.

- instead of throwing these 5 cells out, I paralleled them in pairs and then added 4 CALB 180 cells to my pack. This gave me 1 extra cell, for a total of 41 cells, adding 3.2V to my pack voltage.

- since then I carefully set current limits on Soliton1 to give me plenty of acceleration, yet stay safely under 3C battery currents. Around the same time I also designed MiniBMS and its been working in my car ever since.

- I made 100Amp "bad boy" charger, which is basically a big ass full wave rectifier, dumping rectified AC mains straight into my battery. I use it on occasions when I need to make multiple trips in one day and need to quickly boost my battery. Otherwise I rely on my trusted Zivan NG3 for overnight charging.

- I spent a few months trying to get my Paktrakr to stop glitching. Tried everything and then some, with marginal improvements. Finally gave up and trashed it. Instead I designed my own EV Display from scratch, knowing what essential data I need and what I can do without. It turned out better than I ever expected, I am now completely relying on it and it hasn't failed me yet.

All above changes were done earlier this year, in the past 3-4 months or so I have not changed a single thing in the car, which is remarkable, considering how much tweaking I was doing in prior months. I suppose every project has its final state, and I might have reached it with this car.

I drive this car every day and absolutely love it. I like how the tires chirp when I floor it from the stop line, leaving most gassers behind. Its also fun to pass slower traffic and let them see the electric logo on the back. Who says electrics are slow?

I couldn't have done it without support of many folks on this forum, so thanks everyone who helped me out!

 

Glad to hear things are still running smooth for you as well.

 

That all sounds very good and also encouraging for those of us who are wanting to make the jump to lithium. Good work on the Protege man... looks great! Very glad to hear you've driven so many miles and all is still going well.

 

Glad to hear everything is working smoothly. I'm very happy with my EV Display as well.

 

I suppose it's a poor comment coming 2 years after the start of this thread, but for what it's worth: Front wheel drive cars (and many new rear drive cars) are designed to take the entire drivetrain and front suspension out the bottom of the car on the subframe. You set it on a bench and work on everything in one place, not on your back. Raise the car on jackstands (a lift is better but few hobbyists have one) put a piece of plywood on a rented transmission jack, remove subframe bolts, and it's out. Just some advice from an experienced ICE guy. It's better to build adapters, mounts and such on your workbench or home made table with casters than in, under and around the engine bay.

Separately, what an awesome result and the start of a new cottage bms business! Do you run your power steering and a/c off the motor, or did I miss that? (I read the whole thread all in one sitting, so it's a little fuzzy to me).

 

That's how you're supposed to do it with my Fiero as well but instead of dealing with rusted subframe bolts and disconnnecting brake components I pulled mine out of the top. Not so easy to jack a car 3+ft in the air without a lift either. I also installed my motor and adapter plate by hand instead of using a hoist, so don't go by what I say

 

Glad to hear things are going well Dimitri. I'm pretty much like you, enjoy driving the car, use it for almost all my driving, and it is unEVentful these days, just get in and go. Very reliable and routine now. I find almost no one notices the car is electric, despite the chrome "Electric" signs on both front fenders, back hatch, and 8 1/2" x 11" signs in back side windows that say "Electric" in large letters and give some stats on it. I guess you need something larger, like Dan has on his car.

 

Here's another thumbs up for your EVDisplay. It's working great after 700 miles so far.

 

Time for another short update.

Just passed 100,000 mile mark on odometer, of which 15,000 are electric miles.

Few months ago I had to replace front left wheel bearings, which gave out and made lots of loud noise. I also replaced clicking right CV half shaft around same time. I guess its not unusual to do these things for a 8 year old car which had likely been abused by previous owner. None of these things are EV related.

I have zero EV related updates, everything just works. I rely entirely on EV Display's SOC gauge and my BMS for battery status, which has not failed me yet.

Soliton1 is running strong, recently upgraded to v1.4 firmware, which allows automatic water pump control, so it doesn't spin unless cooling is needed, so I wired my water pump via relay to take advantage of this new feature.

Car is used daily, but I usually drive short distances around town, so I don't accumulate huge mileage, hence don't update this blog often. Will update in another 5,000 miles or so.

 

Good to hear. I assume you are still running on all the original cells? I remember you seemed to have a mixed bunch with a large range of capacity.

 

All original cells are still in the car, but I paired some weak TS cells and compensated the voltage by adding 4 180AH CALBs. That was long time ago, I believe I documented it somewhere earlier in this thread. I haven't touched the battery in the past year or more, haven't even looked at it for months now.

 

26,000 miles update

Had some issues in past few weeks, which could have been avoided if I wasn't so lazy, or did not live by "if it ain't broke, don't fix it" rule

First my throttle linkage broke off where its attached to the arm of the throttle pot. It was a poor job, which I meant to fix eventually, see above rule , so it finally gave in....in the middle of a road... . I connected it back with some nylon thread and limped home, then fixed it properly.

Few days after that my Soliton1 released magic smoke, again in the middle of the road ( ironically, same spot where throttle broke, must be a cursed spot ), had to call a tow truck to get home. My Soliton1 was original Beta unit, first one to ever leave EVNetics into customer's hands. Since then Sebastien offered me to bring it back in to update its guts to real production version, but I declined, see above rule again . Well, now its all up to date, with new magic smoke safely locked inside.

Since upgraded Soliton required setup of all parameters again, I decided to bump up max battery current a little, from 450A to 500A, just to get a little more zoom-zoom when needed. That must have been just the last drop in the bucket for IOTA DC/DC converter, which promptly released its own magic smoke on the next drive. Of course I knew for a long time that I needed to add an inductor to protect DC/DC from the ripple currents, afterall its been covered to death on this forum and I read all of it, but.....see the above rule again.

So now I got the inductor and new shiny DC converter from EV Source.

Car is back in business, EV Grin is back on

 

Oh, I forgot to mention. Few months back one of my original TS cells died. It was peculiar death, out of the blue it developed significant self discharge, like 5 AH per day or so, while still working OK. This prompted me to keep boosting it with a single cell charger to keep it top balanced with other cells. I got tired of doing that quickly and finally decided to take out this cell along with some other TS cells I had paired earlier and replace them all with CALB 180AH cells, at the same time adding a couple more for more voltage/capacity. Once done, I ended up with 46S pack, of which 30 cells are original TS 160AH and 16 CALB 180AH. Since my pack voltage increased I also had to swap my Zivan NG3 for Elcon 2500, which fit perfectly under the hood at the same spot, so it was minimum work.

When I removed the cell which developed self discharge, it was still in perfect geometric shape and had normal OCV voltage, but after a few days of sitting in the garage it ballooned and dropped to zero voltage, so I took it to the recycling yard. It must have been a factory defect which developed over time, since this cell was never abused any more than any other cells and worked fine for over 2 years and did not seem any different than any other cells until it died.

 

Good to see you're still rolling. Other than the ones you replaced how is the capacity holding up on the other original cells?

 

After I added new CALB cells and rebalanced the pack, I drove it until first BMS alerts came in. I counted 150AH of useful capacity, limited by one cell, the first one to raise LVC alerts. I cannot tell how much this cell is lower compared to the next low cell, but I am OK with 150AH, so I will keep driving until this cell or some other cell becomes the weakest point, enough to trigger next cell swap project.