[ElectriCar]

So when did you buy them and how many miles on them now. I've read where one guy was pulling 2c regularly with occasional 3c on his commute and only had like 7000 miles and lost a cell. Others were starting to fail he thought. But he has the older cells I think he bought in early 2008 before the addition of yttrium doping.

[F16bmathis]

Originally Posted by ElectriCar

How's this project coming along? I'm interested in the newest TS cells now.

Did you get the newest ones?

Did you get a closely matched set?

Early on I was turned off by TS cells because of higher internal resistance = higher heat generation = wasted power on heating batteries.

I'm searching hard for ir of TS cells. Hi Power is <2mo, Calb is <1. TS used to be like 3. Doesn't sound like much but it is triple the Calb thus triple the wasted power! That's one reason I'm going away from lead!

To recharge my pack of US2200XC lead, nearly 20% of the input power at 28 amps is in the form of heat if my reasoning is correct. Basically my recharge last night wasted enough power to increase the 1500lb pack temperature 5 degrees F. That equates to about 2.1kw! All after only traveling 11 miles.

Project is pretty much done, meaning I'm allready looking to do more!
I did get the newest ones, I think, bought one from an E-Bay vendor to test, the other 45 from Arizona, they have them here in the US. The set was matched except for the one I bought on E-bay, and after a couple cycles, its balanced in with the others. I have the MiniBMS installed, and cause I can't seem to throw away enough cash, I also bought a touch screen BMS that shows E-F, Battery V, Battery Amps, and shows all batteries voltages, and the highest and lowest voltage plus temp of 6 areas of batterys.

The Thundersky's have increased my range from the lead acid's in winter from 10 miles to about 65 miles, summer is even better. I've allready got 2000 miles on the Thundersky's. During summer, voltage did not sag enough to set off the LV alarm even with the Zilla and flooring it in 1st gear. During 10-20 degrees, I have to let off the juice some, or it'll alarm, but its still a faster car than stock ICE. Helps I dropped 1000 lbs of LA weight!
www.evalbum.com/1752

[F16bmathis]

Originally Posted by ElectriCar

So when did you buy them and how many miles on them now. I've read where one guy was pulling 2c regularly with occasional 3c on his commute and only had like 7000 miles and lost a cell. Others were starting to fail he thought. But he has the older cells I think he bought in early 2008 before the addition of yttrium doping.

I bought mine a few posts back, Oct 2010? I've got just over 2000 miles on them. Had been pulling 1K amps through my Zilla till it had a hiccup, now I'm pulling over 1K on the motor side with a Curtis 1231C 500A modified to 650 or so I think.

Did he have a BMS system? If so, which one?

We've got an El-Camino here that does not have a BMS, yet... batteries are doing fine so far. Mini BMS is on order after the guy saw mine in action!

[ElectriCar]

Originally Posted by F16bmathis

Doesn't voltage equal top speed, and amps equals acceleration? My 144 pack had 80 mph top speed, and the 400 amps (limited in Zilla) had great acceleration.

No. They both work together. Check the site wiki about voltage, amps & power. Don't recall how it is listed but it is very informative.

Electricity is analogous to water in that voltage functions like pressure, amperage is like flow. You have to have pressure to force electron flow which is amps.

Yes higher voltage will allow faster speed because it will make more current flow through a given load.

You also have to have voltage to overcome resistance. Resistance is encountered in your wiring, bad connections, internal resistance of your batteries and the motor itself. Smaller wire has higher resistance to current flow. Installing larger wiring will facilitate efficient current flow, particularly important at higher amps. I run parallel 1/0 through the pack and single 4/0 in places under the hood.

FYI for you Zilla owners: If you're drawing 1000A through a single 2/0 wire you're wasting some serious voltage in the process. If your wiring loop end to end from controller through the pack, contactors and back is 80 feet long, you're losing 6.4V in the wire. That's the equivalent of giving up 2 batteries when you hammer it! I use two parallel 1/0 which would only eat 3.97V, much better but not good. Using parallel 4/0 would get you down to only losing 1.98V in an 80' loop.

[F16bmathis]

Originally Posted by ElectriCar

No. They both work together. Check the site wiki about voltage, amps & power. Don't recall how it is listed but it is very informative.

Electricity is analogous to water in that voltage functions like pressure, amperage is like flow. You have to have pressure to force electron flow which is amps.

Yes higher voltage will allow faster speed because it will make more current flow through a given load.

You also have to have voltage to overcome resistance. Resistance is encountered in your wiring, bad connections, internal resistance of your batteries and the motor itself. Smaller wire has higher resistance to current flow. Installing larger wiring will facilitate efficient current flow, particularly important at higher amps. I run parallel 1/0 through the pack and single 4/0 in places under the hood.

FYI for you Zilla owners: If you're drawing 1000A through a single 2/0 wire you're wasting some serious voltage in the process. If your wiring loop end to end from controller through the pack, contactors and back is 80 feet long, you're losing 6.4V in the wire. That's the equivalent of giving up 2 batteries when you hammer it! I use two parallel 1/0 which would only eat 3.97V, much better but not good. Using parallel 4/0 would get you down to only losing 1.98V in an 80' loop.

You know, I never actually measured the distance of all the 2/0 cables, but I'm going with closer to a little over 20 feet. My intent is to install 4/0 when it gets warmer. Evey little bit helps.

[ElectriCar]

Originally Posted by F16bmathis

You know, I never actually measured the distance of all the 2/0 cables, but I'm going with closer to a little over 20 feet. My intent is to install 4/0 when it gets warmer. Evey little bit helps.

I took my truck on a speed run and hit 85 with it, later to find out with a bad connection. I saw you hit 78 or so. Could your wires have been part of why you couldn't go faster? Wasting 5-6 volts is a lot of wasted juice!

During the run I had a connection melting so some of the power was being wasted. How fast could I have gone had it been a good connection? Don't know but a little faster for sure! Had you had larger wiring you likely would have been faster!

I run 232ah US2200XC lead now. But those days are short lived. I'm upgrading to Calb 240ah x 48 pieces I think. I want over 100 miles range. People are always asking and when you say 30 it sort of throws a wet rag on it you know? Of course the larger the cell and lower C you draw the longer they will last so that is another reason to push my budget a little.

If you are running 1000A or close to it at times, you should probably do the parallel 4/0. When you run the power through two parallel wires instead of one, you're splitting the load and cutting your losses by half compared to one wire.

[DIYguy]

Originally Posted by ElectriCar

I'm upgrading to Calb 240ah x 48 pieces I think.

Are u using the Curtis controller still? Aren't u worried about the higher pack voltage??

[ElectriCar]

Well this is what I know. The Zivan charges up now at 186V or so. As soon as you unplug it, the pack V drops to about 160 in seconds. How fast do these batteries settle out?

As a safety precaution, I wired the Zivan aux. contacts through the controls so if I'm charging, the controller can't be energized so it won't see that voltage when I'm charging.

Now from the data I've seen, the cells will be resting at 3.35 or so volts each or about 161V resting with a 48 cell pack, a full 19V below what the Curtis controller can handle. 162V is about what I see NOW with the residual surface charge. So this is all good. Charging voltage spec is 3.6V so that's 173V, below what I charge with now.

My main thing is maxing my voltage so as to minimize current draw thus maximizing life. Higher voltage does that. Larger cell AH does also. Unfortunately they don't make the 240Ah cells now according to Calb spokesman.

[DIYguy]

Originally Posted by ElectriCar

Now from the data I've seen, the cells will be resting at 3.35 or so volts each or about 161V resting with a 48 cell pack, a full 19V below what the Curtis controller can handle. 162V is about what I see NOW with the residual surface charge. So this is all good. Charging voltage spec is 3.6V so that's 173V, below what I charge with now.

My main thing is maxing my voltage so as to minimize current draw thus maximizing life. Higher voltage does that. Larger cell AH does also. Unfortunately they don't make the 240Ah cells now according to Calb spokesman.

Oh ok, I didn't know the Curtis was ok that high on voltage. I really like the idea of running a controller that will handle a pack voltage much higher than the motor and the ability to program what the motor will see. My pack will be 208 volts and I'll limit the motor to 160. This reduces battery current even further. I am going with 65 of the Calb 180 ah which should give me right about 100 miles range.

[ElectriCar]

You also have to be ok with the DC-DC converter, which mine is rated at 190. So you have a controller to handle that much voltage? Wow. That should work out good if the motor can handle the voltage. I've heard of my FB1-4001 running on 180V so that's ok too.

I just have to get the charger reconfigured for the proper charge profile and the controller settings changed if need be. I'll be getting with Bob at EV America about the controller.