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Discussion Starter #1
How does this package sound for drag racing?

"300V/14Ah is all you need, drag race only one minute, speed is the key, therefore battery must be light weight, I will suggest 6 packs of 48V(52.8V)/28Ah in series = 288V(323.4V)/28Ah in skeleton pack, one IM to connect them together with LED reading."

I need to make sure the two 11" Netgain motors will work with this pack. I sent this info to George to get his opinion. I am all ears fellows!:p
 

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the problem with that is the C rate... a small AH pack is just fine, but assuming you are using the Zilla 2K, you could have peaks at 2000 battery amps which would be 142.8C for the 14AH pack and 71.4C for the 28AH pack. If the batteries are even capable of that kind of discharge I'm sure they wouldn't last that many cycles and I'm sure the voltage sag would be so bad you wouldn't be making much power.

A small pack is great, but you'll have to make sure they can put out the required current at a voltage you are happy with.
 

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I can't figure out what you're after. In some posts, in various threads, it seemed as if you were ready and willing to spend the moeny necessary to put record-setting numbers on the board. On the other hand, it seems as if you're trying to find a cheaper way out.

There's really no cheap or easy way around it - you need one monster of a battery pack, if putting sub-10 second times on the clock is your goal. It has to be capable of over a half of a mega watt of power, repeatedly, and consistently. That means only the highest quality high-power cells available will do.

Back when WZ and Smokescreen were running 11s, some of WZ's log files were picked apart and one of the suspected barriers to better top end, and overall, performance was voltage sag. This was prety much confirmed when WZ started running with the new Kokam pack. Voltage sag is a thing of the past for it, and the car just keeps pulling. The same goes for Rocket. So Kokam pouch or A123 cylindrical both work. The main thing is just building a monster pack that won't sag, won't quit, won't fail.

Same thing for the controller. You have a Zilla, just start pounding on it. Worry about a higher power replacement when you have exceeded its capabilities. By then, there may be something available, and by having proved you and your EV's abilities, you will be at the head of the line of preferred customers to get one.

I would also give consideration to not doing all of the projects you have planned. Just build the Camaro. I would even put the street car on hold, if I were you. By loading one basket with every egg you can stuff in it, you'll gain a lot of experience and hopefully open some new doors. What you really want is for one of the battery manufacturers to see the value in putting their product in your race car. Approaching them now, as a relative unknown, is going to do more harm than good later. I'm actually planning on sponsorship for some things, but I want them to see me before they hear me.

That's my opinion, you asked for it...;)

Oh yeah, I agree with rw about the C-rate. You would be pushing them to literal death. You want to have somewhere between 2 & 3K amps at no more than 40-50C, depending on what cells you end up with. One of the most important facts you need to know when looking for cells for a race pack is the maximum c-rate. Total amp-hours times the c-rate equals the current you have on tap.
 

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Discussion Starter #4
Todd,

I am just throwing things out there to see reactions and opinions, remember I am no electrical engineer so these calculations are a learning experience for me. I thought I needed a "stronger pack", but this was sent to me today by a battery manufacturer. ;)

I can't figure out what you're after. In some posts, in various threads, it seemed as if you were ready and willing to spend the moeny necessary to put record-setting numbers on the board. On the other hand, it seems as if you're trying to find a cheaper way out.

There's really no cheap or easy way around it - you need one monster of a battery pack, if putting sub-10 second times on the clock is your goal. It has to be capable of over a half of a mega watt of power, repeatedly, and consistently. That means only the highest quality high-power cells available will do.

Back when WZ and Smokescreen were running 11s, some of WZ's log files were picked apart and one of the suspected barriers to better top end, and overall, performance was voltage sag. This was prety much confirmed when WZ started running with the new Kokam pack. Voltage sag is a thing of the past for it, and the car just keeps pulling. The same goes for Rocket. So Kokam pouch or A123 cylindrical both work. The main thing is just building a monster pack that won't sag, won't quit, won't fail.

Same thing for the controller. You have a Zilla, just start pounding on it. Worry about a higher power replacement when you have exceeded its capabilities. By then, there may be something available, and by having proved you and your EV's abilities, you will be at the head of the line of preferred customers to get one.

I would also give consideration to not doing all of the projects you have planned. Just build the Camaro. I would even put the street car on hold, if I were you. By loading one basket with every egg you can stuff in it, you'll gain a lot of experience and hopefully open some new doors. What you really want is for one of the battery manufacturers to see the value in putting their product in your race car. Approaching them now, as a relative unknown, is going to do more harm than good later. I'm actually planning on sponsorship for some things, but I want them to see me before they hear me.

That's my opinion, you asked for it...;)

Oh yeah, I agree with rw about the C-rate. You would be pushing them to literal death. You want to have somewhere between 2 & 3K amps at no more than 40-50C, depending on what cells you end up with. One of the most important facts you need to know when looking for cells for a race pack is the maximum c-rate. Total amp-hours times the c-rate equals the current you have on tap.
 

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Discussion Starter #5
This was presented to me by a potential sponsor, that is why I posted it. These cells have a very high C-Rating, but the "suggested Pack" was lacking the Amp-Hours in my and now your opinions. :D

Approaching them now, as a relative unknown, is going to do more harm than good later. I'm actually planning on sponsorship for some things, but I want them to see me before they hear me.

That's my opinion, you asked for it...;)

Oh yeah, I agree with rw about the C-rate. You would be pushing them to literal death. You want to have somewhere between 2 & 3K amps at no more than 40-50C, depending on what cells you end up with. One of the most important facts you need to know when looking for cells for a race pack is the maximum c-rate. Total amp-hours times the c-rate equals the current you have on tap.
 

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I can't figure out what you're after. In some posts, in various threads, it seemed as if you were ready and willing to spend the moeny necessary to put record-setting numbers on the board. On the other hand, it seems as if you're trying to find a cheaper way out.

There's really no cheap or easy way around it - you need one monster of a battery pack, if putting sub-10 second times on the clock is your goal. It has to be capable of over a half of a mega watt of power, repeatedly, and consistently. That means only the highest quality high-power cells available will do.

Back when WZ and Smokescreen were running 11s, some of WZ's log files were picked apart and one of the suspected barriers to better top end, and overall, performance was voltage sag. This was prety much confirmed when WZ started running with the new Kokam pack. Voltage sag is a thing of the past for it, and the car just keeps pulling. The same goes for Rocket. So Kokam pouch or A123 cylindrical both work. The main thing is just building a monster pack that won't sag, won't quit, won't fail.

Same thing for the controller. You have a Zilla, just start pounding on it. Worry about a higher power replacement when you have exceeded its capabilities. By then, there may be something available, and by having proved you and your EV's abilities, you will be at the head of the line of preferred customers to get one.

I would also give consideration to not doing all of the projects you have planned. Just build the Camaro. I would even put the street car on hold, if I were you. By loading one basket with every egg you can stuff in it, you'll gain a lot of experience and hopefully open some new doors. What you really want is for one of the battery manufacturers to see the value in putting their product in your race car. Approaching them now, as a relative unknown, is going to do more harm than good later. I'm actually planning on sponsorship for some things, but I want them to see me before they hear me.

That's my opinion, you asked for it...;)

Oh yeah, I agree with rw about the C-rate. You would be pushing them to literal death. You want to have somewhere between 2 & 3K amps at no more than 40-50C, depending on what cells you end up with. One of the most important facts you need to know when looking for cells for a race pack is the maximum c-rate. Total amp-hours times the c-rate equals the current you have on tap.
A LOT of VERY good advice in this post. Well put Todd.
 
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