[mizlplix]

It's good to see you represented on the forum. Sometimes it gets lonely in here...LOL

Miz

[HPEVS]

Hi Miz,

I've seen some of your post's. I would like to see pics of your project sometime. Are you using the torque converter with your powerglide?

[somanywelps]

Originally Posted by HPEVS

Somanywelps: What are you looking for when you say beefier? 144 volt is coming soon, but the power level is virtually the same as the AC50 is now running on 115 volts. We are still developing the "AC75", it's a torque moster, but drops off earlier in the RPM range compared to the AC50. End result, almost the same HP, runs cooler though.

I was thinking 100kw, 150kw, 200kw peak, etc.

There's an interesting controller called the "scott drive", it's a 150kw peak. (Greenstage is just a reseller, there's a thread in controllers)

[mizlplix]

Most of my car is here:

http://www.diyelectriccar.com/forums...ild-59659.html


No, no torque converter. I used an old TCI Oval track race transmission, with a manual shift valve body.

I was running 32" tall 7.00/15 tires, so the rear axle ratio 6.14:1 gave me 55mph in low, and 95mph in high, at a 6,500 motor RPM.

I did have a #46 controller error but tracked it down to an incorrectly wired Pot 2. With it fixed, all is good.

I find that initial take-off to be a little soft, so I am playing around with controller settings. Also, regen comes on softly and grows slowly and needs ramping up too.

Other than that, I like the combination.

Miz

[tomofreno]

Hi Brian,

Question related to discussion in mixlplix thread. What would you recommend as the max number of cells to run with the new Curtis 144V controller? 49?

[HPEVS]

Originally Posted by tomofreno

Hi Brian,

Question related to discussion in mixlplix thread. What would you recommend as the max number of cells to run with the new Curtis 144V controller? 49?

Hi Tom,

We are running 47 on the Scion, I have some over voltage trips, so I would say 46. The voltage is much tighter on the 144 volt controller since it is designed for lithium batteries where the full charge voltage and nominal voltages are closer together. The 96 volt controllers were designed around lead acid batteries where you can see 126v full charge voltages.

Brian

[tomofreno]

Well darn. I thought with controller max voltage of 175V I would be able to run 49 for 157V nominal voltage, 167V after full charge, giving similar margin to what I now have with the 130V max controller and nominal 115V, 122V after full charge (36 CALB cells).

[HPEVS]

Originally Posted by tomofreno

Well darn. I thought with controller max voltage of 175V I would be able to run 49 for 157V nominal voltage, 167V after full charge, giving similar margin to what I now have with the 130V max controller and nominal 115V, 122V after full charge (36 CALB cells).

Just checked on it, 170VDC max. so it looks like 46 is it. I'm going to do some more testing with the 47 cells though. There is some question now on the full charge voltage of the CALB cells. I think it is 3.7 but someone said the other day it's 3.6.

I'm going to collect some data and should be able to generate graphs on capacity when charging to 3.7 and 3.6 VPC, we'll see what happens.

[frodus]

If you do use 3.6V and only charge to 3.6V per cell, they won't sacrifice much, as there's hardly any charge above 3.6V anyway, it's miniscule.

Another thing to consider, is even if it does work, and someone fully charges the pack, and then goes down the hill and tries to activate Regenerative Braking, you may have issues there as well.

[tomofreno]

I use the minibms so cells shunt at 3.5V. Within 20 minutes the pack relaxes to less than 124V, and within a couple hours they are less than 123V. Just driving 2/10 mile and stopping they are down around 120V. I drive down about 1/2 mile long hill after that and if I keep regen currents 25 to 50A the pack V remains below 123V. Always amazes me I can run that much current into them right after full charge and less than 2Ah used and they don't go higher in voltage.

Were the high voltage warnings you've had due to regen currents? If so, do you know their magnitude? I'm using the regen limiting map to limit max regen to about 140A. That is about what I get if I remove my foot from the accelerator when traveling at 50+ mph for a quick stop - don't want to over-volt my cells if I have to emergency stop not long after full charge. Also have the user_overvoltage parameter set to 130% or 124.8V. I have exceeded it a couple times, regen cuts out, and the car accelerates down the hill.

Yes, 3.6 is the max voltage CALB recommends.