Speed Runners ~ How Fast Did You Go Today?

[vwturbowolf]

Log looks great with the 150mph vendetta pass built in perfect pass in my finger

 

[K-BASH]

Log looks great with the 150mph vendetta pass built in perfect pass in my finger View attachment 217256

1 6sp??????nice min V

 

[vwturbowolf]

1 6sp??????nice min V

5000cnhl 70c one battery.

18.6 min
If I can get My minimum voltage up to 20v that would be a 160pass.
The 5000 I have has had a long life and it’s still doing well

 

[K-BASH]

5000cnhl 70c one battery.

18.6 min
If I can get My minimum voltage up to 20v that would be a 160pass.
The 5000 I have has had a long life and it’s still doing well

I use calculator at 17.5v if it'll hold better than that your doing good..if you can hold 20v thats outstanding...your PP finger an 6000ft road will also help ya...awesome to see you having successful runs after some isssues.
Hard to beat the G-series

 

[K-BASH]

5000cnhl 70c one battery.

18.6 min
If I can get My minimum voltage up to 20v that would be a 160pass.
The 5000 I have has had a long life and it’s still doing well

Looks like ya got a little aggressive 90-100%I do the same thing,think it's cause I like to hit wot as it passes me causing me to do it...ya need to slow your PP down a little there bud..

 

[vwturbowolf]

Looks like ya got a little aggressive 90-100%I do the same thing,think it's cause I like to hit wot as it passes me causing me to do it...ya need to slow your PP down a little there bud..

View attachment 217306

Yup yup. That’s exactly what happen.
Once it gets closer to my I ramp up faster. That last bit effects the battery a lot.

 

[K-BASH]

Yup yup. That’s exactly what happen.
Once it gets closer to my I ramp up faster. That last bit effects the battery a lot.

Imo 90-100 is the most important spot to get right for highest voltage. Also the hardest for me to get right

 

[Notorious J]

5000cnhl 70c one battery.

18.6 min
If I can get My minimum voltage up to 20v that would be a 160pass.
The 5000 I have has had a long life and it’s still doing well

I use calculator at 17.5v if it'll hold better than that your doing good..if you can hold 20v thats outstanding...your PP finger an 6000ft road will also help ya...awesome to see you having successful runs after some isssues.
Hard to beat the G-series

I've been going back and forth with Josh Barker at MaxAmps about how to get a battery that might hold up better than what's currently available. My guess is building this battery would be ridiculously expensive, but how he breaks it down is interesting. Here's his take on a better 6s battery for speed runs:

Johnny,



I wouldn’t say your impression is wrong. The benefits of a given cell change with size however. As a cell grows in size it’s max capable continuous C rate actually decreases after a certain capacity. The reason for this is that the cell is incapable of maintaining internal temperature over such a large surface area. This leads to higher IR and heat build up at higher amp loads. This in turn causes more voltage sag, which builds more heat in use. If C rate stayed the same as a cell grew in size then yes higher capacity would always be better. Unfortunately that is not the case.



The highest power output options come from smaller cells wired in parallel to achieve those higher capacities. This way you have cells capable of maintaining their portion of the load more efficiently and you spread out the amp load across multiple cells. In all reality while a cell may be able to hold some kind of voltage at 120C, running it at or near this rate is a death sentence for any battery. We tend to recommend a continuous rate of about ¼ of our max listed C rate. Short bursts at a higher rate are fine but any extended use at those rates is going to lead to premature failure. The highest voltage under load at any of these rates is going to be in a multi-P configuration though. Even our 7125mah pack I mentioned should be a solid upgrade over your 6800mah pack you were running as it is 3P. Going with lower capacity cells our 1450mah cell has been one of our most power dense options and has been effective at 50C for the full duration of discharge. Building this into a 3-4P option would be the option that would likely provide the highest voltage under load. Doing so would likely mean further modification to your tray space however as at this cell count the battery is going to be fairly large.

4350Mah 6s3p - 68mm x 35mm x 171mm, 840g

5800Mah 6s4p - 68mm x 35mm x 228mm, 1128g

Or 68mm x 70mm x 114mm SBS build



Hope this helps! Let me know if any of these options sound viable and I will send a quote your way.



Josh Barker

Director of Business Development

www.MaxAmps.com

 

[LibertyMKiii]

I've been going back and forth with Josh Barker at MaxAmps about how to get a battery that might hold up better than what's currently available. My guess is building this battery would be ridiculously expensive, but how he breaks it down is interesting. Here's his take on a better 6s battery for speed runs:

Johnny,



I wouldn’t say your impression is wrong. The benefits of a given cell change with size however. As a cell grows in size it’s max capable continuous C rate actually decreases after a certain capacity. The reason for this is that the cell is incapable of maintaining internal temperature over such a large surface area. This leads to higher IR and heat build up at higher amp loads. This in turn causes more voltage sag, which builds more heat in use. If C rate stayed the same as a cell grew in size then yes higher capacity would always be better. Unfortunately that is not the case.



The highest power output options come from smaller cells wired in parallel to achieve those higher capacities. This way you have cells capable of maintaining their portion of the load more efficiently and you spread out the amp load across multiple cells. In all reality while a cell may be able to hold some kind of voltage at 120C, running it at or near this rate is a death sentence for any battery. We tend to recommend a continuous rate of about ¼ of our max listed C rate. Short bursts at a higher rate are fine but any extended use at those rates is going to lead to premature failure. The highest voltage under load at any of these rates is going to be in a multi-P configuration though. Even our 7125mah pack I mentioned should be a solid upgrade over your 6800mah pack you were running as it is 3P. Going with lower capacity cells our 1450mah cell has been one of our most power dense options and has been effective at 50C for the full duration of discharge. Building this into a 3-4P option would be the option that would likely provide the highest voltage under load. Doing so would likely mean further modification to your tray space however as at this cell count the battery is going to be fairly large.

4350Mah 6s3p - 68mm x 35mm x 171mm, 840g

5800Mah 6s4p - 68mm x 35mm x 228mm, 1128g

Or 68mm x 70mm x 114mm SBS build



Hope this helps! Let me know if any of these options sound viable and I will send a quote your way.



Josh Barker

Director of Business Development

www.MaxAmps.com

Not sure if anything has changed but every test I have seen indicates MaxAmps cells are not great for high amperage discharge.
They seem to be more like 5-15c cells that are good for long run times and very stable for many years if not pushed hard.

You can find them at the bottom of the list:

Newer testing where parameters of test were edited for more accurate results:

 

[TN-RC]

Not sure if anything has changed but every test I have seen indicates MaxAmps cells are not great for high amperage discharge.
They seem to be more like 5-15c cells that are good for long run times and very stable for many years if not pushed hard.

You can find them at the bottom of the list:

View attachment 217338

Newer testing where parameters of test were edited for more accurate results:
View attachment 217339

Do you have a battery tester?

 

[LibertyMKiii]

Do you have a battery tester?

It is a long running threat on the RC Groups forum. I wish I had test equipment like that...

 

[K-BASH]

I've been going back and forth with Josh Barker at MaxAmps about how to get a battery that might hold up better than what's currently available. My guess is building this battery would be ridiculously expensive, but how he breaks it down is interesting. Here's his take on a better 6s battery for speed runs:

Johnny,



I wouldn’t say your impression is wrong. The benefits of a given cell change with size however. As a cell grows in size it’s max capable continuous C rate actually decreases after a certain capacity. The reason for this is that the cell is incapable of maintaining internal temperature over such a large surface area. This leads to higher IR and heat build up at higher amp loads. This in turn causes more voltage sag, which builds more heat in use. If C rate stayed the same as a cell grew in size then yes higher capacity would always be better. Unfortunately that is not the case.



The highest power output options come from smaller cells wired in parallel to achieve those higher capacities. This way you have cells capable of maintaining their portion of the load more efficiently and you spread out the amp load across multiple cells. In all reality while a cell may be able to hold some kind of voltage at 120C, running it at or near this rate is a death sentence for any battery. We tend to recommend a continuous rate of about ¼ of our max listed C rate. Short bursts at a higher rate are fine but any extended use at those rates is going to lead to premature failure. The highest voltage under load at any of these rates is going to be in a multi-P configuration though. Even our 7125mah pack I mentioned should be a solid upgrade over your 6800mah pack you were running as it is 3P. Going with lower capacity cells our 1450mah cell has been one of our most power dense options and has been effective at 50C for the full duration of discharge. Building this into a 3-4P option would be the option that would likely provide the highest voltage under load. Doing so would likely mean further modification to your tray space however as at this cell count the battery is going to be fairly large.

4350Mah 6s3p - 68mm x 35mm x 171mm, 840g

5800Mah 6s4p - 68mm x 35mm x 228mm, 1128g

Or 68mm x 70mm x 114mm SBS build



Hope this helps! Let me know if any of these options sound viable and I will send a quote your way.



Josh Barker

Director of Business Development

www.MaxAmps.com

Don't understand the whole heat cause more sag thing...I always get best #'s on 2nd,or 3rd pass with packs......I figured heat was the reason.more heat more performance,IR.

 

[Notorious J]

Not sure if anything has changed but every test I have seen indicates MaxAmps cells are not great for high amperage discharge.
They seem to be more like 5-15c cells that are good for long run times and very stable for many years if not pushed hard.

You can find them at the bottom of the list:

View attachment 217338

Newer testing where parameters of test were edited for more accurate results:
View attachment 217339

He actually explained to me that the ones they sell are meant for longer run times and that his break down would be for a specifically made battery based on his notes. None of the ones you find on the website meet the criteria he talks about.

 

[rotauq]

Don't understand the whole heat cause more sag thing...I always get best #'s on 2nd,or 3rd pass with packs......I figured heat was the reason.more heat more performance,IR.

There is a difference between battery overal temp and micro hotspots in the battery

I don't think RC groups tests list 4p small capacity celled batteries.
For my drones i also use 1300-1500Mah high discharge 6s packs and they do pack a punch. The more parallel cells the more change of problems though. If 4p or even 6p would be our answer, i'd say they would have already existed.
I also believe if a single cell is not capable of offering the ampload (1450@120C is still only capable of 174A) and R and I are not perfectly matched amoung the parallel cells, it will fail quickly

 

[K-BASH]

There is a difference between battery overal temp and micro hotspots in the battery

I don't think RC groups tests list 4p small capacity celled batteries.
For my drones i also use 1300-1500Mah high discharge 6s packs and they do pack a punch. The more parallel cells the more change of problems though. If 4p or even 6p would be our answer, i'd say they would have already existed.
I also believe if a single cell is not capable of offering the ampload (1450@120C is still only capable of 174A) and R and I are not perfectly matched amoung the parallel cells, it will fail quickly

I always wanted to try something like 4×1800-2000mah drone packs all paralleled up..but all the connections would be scary

 

[jondilly1974]

There is a difference between battery overal temp and micro hotspots in the battery

I don't think RC groups tests list 4p small capacity celled batteries.
For my drones i also use 1300-1500Mah high discharge 6s packs and they do pack a punch. The more parallel cells the more change of problems though. If 4p or even 6p would be our answer, i'd say they would have already existed.
I also believe if a single cell is not capable of offering the ampload (1450@120C is still only capable of 174A) and R and I are not perfectly matched amoung the parallel cells, it will fail quickly

SMC SRD 4S packs are 4S2P. You can also figure the additional wire helps with current. You effectively double the amp capacity each time you parallel packs. Same with connectors.

 

[K-BASH]

@jondilly1974. @rotauq are you guys taking the season off...aren't you guys itching to run.jd if ya wanna just send me the Mojave I'll run it for ya buddy...

 

[jondilly1974]

@jondilly1974. @rotauq are you guys taking the season off...aren't you guys itching to run.jd if ya wanna just send me the Mojave I'll run it for ya buddy...

I haven’t had a spare second of time. Gonna be a busy work year. Any spare moment I have goes towards working around the house. Too many projects. I will get there. It might be until summer tho

 

[vwturbowolf]

I haven’t had a spare second of time. Gonna be a busy work year. Any spare moment I have goes towards working around the house. Too many projects. I will get there. It might be until summer tho

I feel this as well.
I have a gutted main floor bathroom at the moment that I haven’t touched in a month.
I wish I could take one day off work to work at home but I’d probably end up sleeping

 

[K-BASH]

I haven’t had a spare second of time. Gonna be a busy work year. Any spare moment I have goes towards working around the house. Too many projects. I will get there. It might be until summer tho

Whatever jd,I'll pm you address case you change your mind.me an the whole rc world are patiently waiting to see the world's fastest Mojave back in action are you sure you don't have covid an need 2 weeks paid off work

Whatever jd,I'll pm you address case you change your mind.me an the whole rc world are patiently waiting to see the world's fastest Mojave back in action are you sure you don't have covid an need 2 weeks paid off work

I got the hook up on ethentic positive covid test results,how do you spell your name????I'm full of um today,tired of seeing traditional speedcars.im itching to see something different