LiPo Testing And The Spreadsheet

[dk10438]

Rcgroups is for aerial stuff, 99% of what is posted on those forums is for planes, helis and drones. MSC Guy does all his testing using EDF jets as his basis for the demands for the batteries.

I take Youtube videos on products with a grain of salt as they are mostly just paid promotions of products.

That and I post things where I spend my time, these test are for rc batteries and aimed at rc users so why not post it here? This is an rc forum isn't it? And how do you know this is the only forum where he posted this? For all you know he has posts on every rc forum there is.

I'm not trying to sound like a jerk but some of you are coming across rather prickish and getting really nitpicky over what he has done with his spare time to get a better understanding of how one battery compares to another. If you don't like it then move on and don't comment there is no need to sit here, piss and moan and tell him what to do with his spare time.

what are talking about? I've barely posed on this thread and I actually said I applaud what @Greywolf74 is doing? and now you're calling me prickish? I was just suggesting a way to monetize this to fund his research. why don't you quote where I was being nitpicky or pissing on his thread?

 

[slick2500]

what are talking about? I've barely posed on this thread and I actually said I applaud what @Greywolf74 is doing? and now you're calling me prickish? I was just suggesting a way to monetize this to fund his research. why don't you quote where I was being nitpicky or pissing on his thread?

No no no not you other people sorry. I should have put another space in there.

 

[SrC]

I did think it was strange but I guess they wanted to see what went wrong, There were no visible signs of damage, just a dead cell.

Yeah I believe Traxxassss would make someine go through hoops like that. What idiots. Basically calling you a thief. Or making sure you aren't one first.

 

[Greywolf74]

Repeatable is one thing. But you have to define the applicability of the initial test conditions for the data to be meaningful. By that I mean, your testing conditions will produce data that will represent the lipo ratings for those conditions, or discharge rate. That does not mean that you could extrapolate those results to other testing conditions and have the results still be applicable without additonal testing for validation.

For example, when you look at rcgroups results postings from mcsguy, the line up changes at various load levels. The panther, for example is not at the same ranking at one load level as it is in another.

While there may be general trends, is highly likely. However the line up will change depending on the load you use for testing.

While it may be scientifically measurable, the load plays an important factor in applicability. Both for measurable difference and perceived difference. Lighter loads will see much smaller changes, bordering on being difficult to perceive a difference.

Thanks, btw for the fascinating thread. I do love these discussions. (And I'm referring to the actual "discussion" portions )

I guess when I started out, I was only concerned with whether or not the stated mAh rates were accurate or not. I figured racers would like to know which packs maintain the highest voltages through the course of a pack down to LVC but I never stopped to compare mAh under load. That being said, from what Ive seen in my tests so far, Id wager the ones that have the least voltage sag probably also have the highest mAh under load but what those numbers are I cant say atm.

I could potentially go back through all of the logs and get either the mAh ratings during say, the 100A tests, or at least the run times and add another point of comparison that could potentially be very meaningful. I appreciate the suggestion and I also appreciate a good constructive back and forth, especially about electronics

@Greywolf74
I applaud your efforts and there's a lot of valid points. Synthetic testing doesn't always translate into real world performance. That being said, controlled testing is the only real way to compare batteries head to head as imperfect as it may be. I'd look into developing a youtube channel to report the results of your tests. Arrma forums is a relatively small user base but if you were able to tap into the larger RC community you might be able to attract a much larger audience.

That is something I have considered. I have a tiny youtube channel already, I just haven't really created much content for it in the last 8 or 10 years. I may end up doing just that.

 

[Greywolf74]

I just did some poking around and the data logger records "mAh out" so the mAh under load info is there in the data logs and the discharge graphs. If I ever get time I might just make a spot for that on my spreadsheet and go back through all of the discharge graphs and tally up those figures but lately Ive been too busy. Maybe thats something Ill do when I officially run out of lipos to test

 

[SP3SWJ]

Very interesting topic ;-)

After more then one year using one of my battery in speed run , (often on Inertial dyno) i decide do some measurement with big current... "big" mean 100A.

Using cheap 15$ car akku tester (0,1ohm) clamp meter and cell voltage meter just load battery for few second - RECORD VIDEO- and later collect data

I have quite good IR meter... but real load is real load chemistry inside start working... warm up ;-)

I have somewhere data collested for every second - but need find in mu PC

I found for other test

If will be someone interested I can tey find more data from test.

From speedrun I have good experience with PINK series CNHL Gplus, interesting fact that 5000mAh 70C work better than GREEN CNHL 9500mAh 90C.

On two parallel battery PINK CNHL 11000mAh battery I can pull 400A during 10 second with battery sag not lower than 26V

On this test when I reach limit of speed i specially pull throttle full next 7 second to measure voltage sag.... but was really OK


;-) end of my boring post ;-)

 

[SP3SWJ]

... and forgot to add some link from dyno test...

On Dyno I start observing that my old batery lost parametres and decide test more detailed battery

on video with load 150Ampera we can see that one cell is weaker in old battery.

 

[JCsRC]

I’d be interested if you tested actual 12.8v deep cycle batteries for Marine, solar, or auto uses. Batteries range from less than $300 for a 100 AH deep cycle battery to over $1000. I would guess the market interest comparatively for those batteries is much larger than for RC. I’m guessing the average person interested in RC just does not have much money to begin with so the market is small or limited, and most RC enthusiasts wont be willing to pay any monthly subscription for very long.

The number of people interested in deep cycle marine batteries would be much larger than RC, and these people are into hobbies that involve much more money such as boating, sailing, car audio, solar, RV, and off grid systems. Of course it would also cost you much more in equipment to test so probably not worth it either way.

This would primarily involve lithium batteries too but AGM and lead acid are good benchmarks to use.

 

[Diem Turner]

Very interesting topic ;-)

After more then one year using one of my battery in speed run , (often on Inertial dyno) i decide do some measurement with big current... "big" mean 100A.

View attachment 263221

Using cheap 15$ car akku tester (0,1ohm) clamp meter and cell voltage meter just load battery for few second - RECORD VIDEO- and later collect data

I have quite good IR meter... but real load is real load chemistry inside start working... warm up ;-)


View attachment 263231


I have somewhere data collested for every second - but need find in mu PC

I found for other test

View attachment 263235

If will be someone interested I can tey find more data from test.

From speedrun I have good experience with PINK series CNHL Gplus, interesting fact that 5000mAh 70C work better than GREEN CNHL 9500mAh 90C.

On two parallel battery PINK CNHL 11000mAh battery I can pull 400A during 10 second with battery sag not lower than 26V

View attachment 263236


View attachment 263237

View attachment 263238

On this test when I reach limit of speed i specially pull throttle full next 7 second to measure voltage sag.... but was really OK


;-) end of my boring post ;-)

Not boring at all my friend

Yeah, the CNHL G+ series is well known in speed running circles as the best performer in CNHL's lineup. I think they're probably the best speed running batteries at a reasonable price and to get more performance, you have to spend a lot more money on something like SMC-SRD or ONYX Power Systems.

That's an awesome rolling road you have there. I really like what you're doing there and I know I'm not the only one who enjoys seeing someone really get into the testing and numbers. Great stuff man

 

[SP3SWJ]

Not boring at all my friend

Yeah, the CNHL G+ series is well known in speed running circles as the best performer in CNHL's lineup. I think they're probably the best speed running batteries at a reasonable price and to get more performance, you have to spend a lot more money on something like SMC-SRD or ONYX Power Systems.

That's an awesome rolling road you have there. I really like what you're doing there and I know I'm not the only one who enjoys seeing someone really get into the testing and numbers. Great stuff man

I know that ONYX is now on top, but competitors not sleep and maybe before winter show interesting propositions for speedrunners.

I have few to test ;-)

And we have where testing on almost road ;-)

4km long

and short track 700 meters

Very interesting is how producer declare "C parameters. I searched some literature how C should be propper metered, but hard to find description. Unfortunatelly on most battery "C" is only marketing ble-ble. Real test on field show battery sag and we have clear i fo from Castle log.

 

[Diem Turner]

I know that ONYX is now on top, but competitors not sleep and maybe before winter show interesting propositions for speedrunners.

I have few to test ;-)

View attachment 263306

And we have where testing on almost road ;-)

4km long

and short track 700 meters

Very interesting is how producer declare "C parameters. I searched some literature how C should be propper metered, but hard to find description. Unfortunatelly on most battery "C" is only marketing ble-ble. Real test on field show battery sag and we have clear i fo from Castle log.

The competition never sleeps That's the beauty of free markets when they work properly.

Yeah, C-ratings are worthless. I suspect that's why you're not finding much documentation on how it's "properly" done because there is no agreed upon standard of how it should be done. Every manufacturer just makes up their own methodology and since there's no standard...it's meaningless.

I'm totally not jealous of that road you have there. I didn't know something like that existed out in the wild. I mean, that's what a speed runner would draw if you asked him to design a perfect speed running test area. That road is amazing. The next time I go to Poland I'm taking my car with me

 

[slick2500]

The competition never sleeps That's the beauty of free markets when they work properly.

Yeah, C-ratings are worthless. I suspect that's why you're not finding much documentation on how it's "properly" done because there is no agreed upon standard of how it should be done. Every manufacturer just makes up their own methodology and since there's no standard...it's meaningless.

I'm totally not jealous of that road you have there. I didn't know something like that existed out in the wild. I mean, that's what a speed runner would draw if you asked him to design a perfect speed running test area. That road is amazing. The next time I go to Poland I'm taking my car with me

I honestly think they just throw darts at a board or it's sort of like pin the tail on the donkey.

 

[Diem Turner]

I honestly think they just throw darts at a board or it's sort of like pin the tail on the donkey.

Or like the South Park episode when the economy crashed and Stan was trying to return Randy's Margaritaville machine.

 

[SP3SWJ]

Unfortunatelly most producer use this tool to "create" C number ... for battery

 

[WickedFog]

I sit here in Discord voice chat with Greywolf every day, for hours on end, and have done so for many months while he has been doing this testing. I can assure you Greywolf knows his chit, and his testing methods are legit and accurate.

And he has been doing this for well over a year, spending a boatload of his own money, just to be able to share his data with the RC community. And it was me that told him he might consider doing a patreon if he wanted to continue doing this testing. The mountain of LiPo batteries he has bought just to do this started making him question whether he should continue.

Just another example of some of Grey's "other" work - we did a collaboration on this project. He came up with the electronics in this, and I did the mechanical design work for the housing.

 

[djrahbee]

Liperior Christmas Sale!

4s 9000mah and 7000mah 50c pretty cheap. And a bunch of other stuff too, that's just what I was eyeballin.

https://rcbattery.com/mega-christmas-sale.html

 

[slick2500]

I sit here in Discord voice chat with Greywolf every day, for hours on end, and have done so for many months while he has been doing this testing. I can assure you Greywolf knows his chit, and his testing methods are legit and accurate.

And he has been doing this for well over a year, spending a boatload of his own money, just to be able to share his data with the RC community. And it was me that told him he might consider doing a patreon if he wanted to continue doing this testing. The mountain of LiPo batteries he has bought just to do this started making him question whether he should continue.

Just another example of some of Grey's "other" work - we did a collaboration on this project. He came up with the electronics in this, and I did the mechanical design work for the housing.

I've never seen anyone in the Discord voice channels.

 

[Moirae]

Liperior Christmas Sale!

4s 9000mah and 7000mah 50c pretty cheap. And a bunch of other stuff too, that's just what I was eyeballin.

https://rcbattery.com/mega-christmas-sale.html

View attachment 263635

Man, that seems like a really good deal. I really don't need more lipos but I'm still tempted.

 

[slick2500]

I know this is going to sound like a stupid question but what kind of application would you use a 5000mah 6s 25c battery in?

 

[Moirae]

I know this is going to sound like a stupid question but what kind of application would you use a 5000mah 6s 25c battery in?

Maybe thats real c