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Old 12-02-2008, 04:36 AM   #91
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Jason,

Where are your sensor leads hooked up on the packs you are testing? This is an important step during the cycling process. You can get higher or lower GFX cycle numbers by placing the sensor leads in different locations. If you are hooking to the main wires than your numbers will be higher vs. testing on the Deans plug.

Please remember many variables need to be taken into consideration when cycling packs.

First and foremost, the GFX is for your personal reference only. I can not compare Humpty's GFX to mine and here's why. Ambient air temp, humidity, and GFX all play a factor in cycle results.

Arizona has a warmer climate w/less humidity than say here in North Carolina. So Humpty's cycle numbers will be different. All GFXs' are different when producing cycle numbers. Some might show more runtime or some might show a lower IR. They are all close but will show different results.

The main thing is the sensor lead location. That will have the largest effect on cycle numbers.

As a side note:

Humpty and myself have known each other for many years. I have the upmost respect for him and he's been with PRS since day one. I use him as a reference in my posts because he knows I will not personally attack, belittle, or trash him via the net. I do pick and cut up with him at times because we are good friends, but we both know when to pick/play and when to be profesional.
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Old 12-02-2008, 09:23 AM   #92
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I'm developing a serious man crush on ThunderPower...

Jason,

Any chance you guys would consider having the balance leads exit the same part of the battery as the main power leads? Having them exit from opposite corners can interfere with the top deck of a number of on-road cars.
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Old 12-02-2008, 10:56 AM   #93
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Jason: We test our packs on the GFX and attach the voltage sensing leads on the 12 guage wire on the pack side connector. This means the connector isn't part of the measurements. The reason why we do this is we found the tension of the male connector would affect the numbers. Since we cycle 100s of packs a week it's hard to always keep chaging the male connectors to make sure they have maximum pressure. This is also a reason why most of our good racers hardwire and why we don't use inboard tubes. When testing a pack though the Deans connector it adds 1 milliohm of IR and reduces the voltage by .04 at 35 amps. This needs to be taken into consideration.

The packs are charged on Hypeion Duo chargers set at 2C. Then they go onto the GFX for discharge down to 6 volts using 35 amps.

As I have been matching cells for more than 20 years and have tested and been using Competition Electronics chargers/matchers ever since they have come on to the scene in the mid 80s. That being said they try to make the best possible charger andn in the case of the GFX they calibrate them and they do the best they can but it's normaly that they aren't all the same. We use 6 GFXs to cycle our packs so numbers can vary.

The goal when cycling our packs is to make sure they all meet what we feel is the minimum specs for that particular pack. Since were cycling them we decided to post the numbers on the box. So this is a refference that helps and as far as I know nobody else does it.

So feel free to post numbers on your packs when you sell them and I will buy some and see how accurate they are on my GFXs. I think the numbers I get could be different than your as well. This is why you can't compare numbers and when we go to the races we see some racers talk about pack numbers and some get all upset because there packs are lower but it turns out there GFX is reading low and the other guys GFX reads high. Than there is the heat of the pack. When one looks at Humptys numbers he will never get these numbers unless he heats the pack.

As you can see there is no real standards of testing and due to all the variables it is to hard to establish one.
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Old 12-02-2008, 11:35 AM   #94
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This is why you can't compare numbers and when we go to the races we see some racers talk about pack numbers and some get all upset because there packs are lower but it turns out there GFX is reading low and the other guys GFX reads high.

Which I guess is why IMHO it makes it almost POINTLESS to put labels on a pack w/ numbers nobody can ever duplicate

Build a GOOD Product and people will buy it w/o the hype...

I guess it's good to see all this competition in the battery market, THUNDER POWER what are you guys working on for the 1 cell LIPO market?
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Old 12-02-2008, 12:28 PM   #95
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Originally Posted by SWTour View Post
Which I guess is why IMHO it makes it almost POINTLESS to put labels on a pack w/ numbers nobody can ever duplicate

Build a GOOD Product and people will buy it w/o the hype...

I guess it's good to see all this competition in the battery market, THUNDER POWER what are you guys working on for the 1 cell LIPO market?
How is it any different than NiMH matching? Do you have your own turbomatcher at home just to verify the #'s were accurate? At least they give racers some feedback, you can't go into a shop and sort through 5 orion packs and have any idea which one is best, here you would at least know which pack was best even if the #'s didn't match your own tests.
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Old 12-02-2008, 01:10 PM   #96
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Jason, for what I understand from the discharging graph that Thunder Power had posted previously in this thread, you did discharge a single cell with the capacity of 5000mAh at 40C. But if it is a 2S2P pack, a single cell should be 2500mAh. Or you used a 3.7V 2P pack to do this test?

My question is why didn't you use the complete 2S2P pack to conduct this 40C discharging test and plot the graph? To discharge a 2S2P/7.4V pack at 40C,the discharging current will be same as to discharge a "half" pack (2P/3.7V). They both take 200A discharging current.

One more question, how did you attach the pack to your equipment when you did the 40C test? and may I know the discharging time also? I will definately do the test when I have your pack on hand and I just want to compare if we will get the same result (graph) as yours. May I do the test by using a complete pack?
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Old 12-02-2008, 04:19 PM   #97
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Default Ordered mine

Ordered mine today !!! At $99.00 you simply cannot beat that price worse, case scenario even if it turns out to be a 35C pack still, an excellent deal. SMC's 28C is $130!!! Trinity's 3800 35C is $89+
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Old 12-02-2008, 05:19 PM   #98
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Originally Posted by trickd122 View Post
Ordered mine today !!! At $99.00 you simply cannot beat that price worse, case scenario even if it turns out to be a 35C pack still, an excellent deal. SMC's 28C is $130!!! Trinity's 3800 35C is $89+
Whered ya order from?
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Old 12-02-2008, 05:31 PM   #99
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Whered ya order from?
Read post #85 above.....
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Old 12-02-2008, 08:22 PM   #100
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Originally Posted by Danny/SMC View Post
Jason: We test our packs on the GFX and attach the voltage sensing leads on the 12 guage wire on the pack side connector. This means the connector isn't part of the measurements. The reason why we do this is we found the tension of the male connector would affect the numbers. Since we cycle 100s of packs a week it's hard to always keep chaging the male connectors to make sure they have maximum pressure. This is also a reason why most of our good racers hardwire and why we don't use inboard tubes. When testing a pack though the Deans connector it adds 1 milliohm of IR and reduces the voltage by .04 at 35 amps. This needs to be taken into consideration.

The packs are charged on Hypeion Duo chargers set at 2C. Then they go onto the GFX for discharge down to 6 volts using 35 amps.

As I have been matching cells for more than 20 years and have tested and been using Competition Electronics chargers/matchers ever since they have come on to the scene in the mid 80s. That being said they try to make the best possible charger andn in the case of the GFX they calibrate them and they do the best they can but it's normaly that they aren't all the same. We use 6 GFXs to cycle our packs so numbers can vary.

The goal when cycling our packs is to make sure they all meet what we feel is the minimum specs for that particular pack. Since were cycling them we decided to post the numbers on the box. So this is a refference that helps and as far as I know nobody else does it.

So feel free to post numbers on your packs when you sell them and I will buy some and see how accurate they are on my GFXs. I think the numbers I get could be different than your as well. This is why you can't compare numbers and when we go to the races we see some racers talk about pack numbers and some get all upset because there packs are lower but it turns out there GFX is reading low and the other guys GFX reads high. Than there is the heat of the pack. When one looks at Humptys numbers he will never get these numbers unless he heats the pack.

As you can see there is no real standards of testing and due to all the variables it is to hard to establish one.
Hello Danny,

Thank you for the detailed reply. We do have a few more questions and concerns and hope you can shed some more light on those:

BTW - We've owned one of our GFX units for almost 7 years now and have quite a bit of experience with it. Please do not assume we lack experience with the unit (as you posted on another forum) because we're not readily aware of what testing procedures may be used by various manufacturers and consumers (we’ve seen 3 different procedures in this thread alone, albeit we are most interested in yours so we can create the most accurate and comparable test result data for everyone).

Today we re-tested the same batteries I published the numbers for in post #84, using the same test equipment and procedures you outlined in post #93. Our hope was to achieve numbers that were the same or at least reasonably closer to the numbers found on the box label for the SMC battery (while also hoping to see an improvement in the numbers for our pack and more accurate and comparable test result data). Again, our goal is to achieve the same testing standard and numbers you are publishing for the packs you sell so we too can publish fair and accurate numbers for the packs we sell.

We charged the batteries at 2C (10 amps) on our Hyperion Duo charger (we have a LOT of test equipment on hand ) and tested them with the sensing leads of the GFX connected to the solder joints of the female Deans Ultra Plug connector on the 12GA power leads of each battery (we agree that removing the male Deans Ultra Plug connector from the equation is a good idea for a number of reasons). However, the test results for the SMC battery were not any closer to the numbers found on the box label. Here are all the numbers for reference:

SMC 5000mAh 28C 7.4V

Numbers from the box label:

IR = 5.4
Seconds = 537
Avg. Voltage = 7.43V
mAh = 5220

Numbers when charged at 1C on our (best) GFX unit, and discharged on the same GFX unit with the sensing leads attached to the solder joints of the male Deans Ultra Plug connector on the GFX leads:

IR = 6.8
Seconds = 529
Avg. Voltage = 7.38V
mAh = 5143

Numbers when charged at 2C on our Hyperion Duo charger, and discharged with the (best) same GFX unit used for the previous test, with the sensing leads attached to the solder joints of the female Deans Ultra Plug connector on the battery leads:

IR = 6.7
Seconds = 522
Avg. Voltage = 7.36V
mAh = 5075


And for added reference:


Thunder Power 5000mAh Pro Race 40C 7.4V

Numbers when charged at 1C on our (best) GFX unit, and discharged on the same GFX unit with the sensing leads attached to the solder joints of the male Deans Ultra Plug connector on the GFX leads:


IR = 5.7
Seconds = 524
Avg. Voltage = 7.44
mAh = 5094

Numbers when charged at 2C on our Hyperion Duo charger, and discharged with the (best) same GFX unit used for the previous test, with the sensing leads attached to the solder joints of the female Deans Ultra Plug connector on the battery leads:

IR = 5.7
Seconds = 507
Avg. Voltage = 7.44V
mAh = 4929

As you can see, the numbers did not improve (nor change much at all) when using the same charger, charge rate and sensing lead connection points you use in your testing.

Even more food for thought is that our best GFX unit charges the batteries to around 8.42-8.43V (the resting voltage of the battery a few minutes after charging ends), and the Hyperion Duo charges the same batteries to just 8.37-8.39V. It’s safe to say that some of the numbers (most noticeably the seconds and mAh numbers) will always look slightly better when discharging a pack charged on this particular GFX unit versus this particular Hyperion Duo unit.

This data in mind, it’s obvious there are still some variations in our equipment and/or testing conditions since we now seem to be using the same equipment and procedures. So, if you agree, the variations likely seem related to differences in:

- Ambient temperature

- Humidity

- Calibration of the charging/discharging/measurement equipment - This is likely the biggest culprit of all, and understandable of course since we’re using hobby-quality and not lab-quality equipment for this testing. However, we also have lab-quality equipment we often use for checking IR/voltage and can use this equipment instead to better standardize our testing if you’d like to purchase the same equipment. This might make it much easier to standardize our results if the variations we’re seeing are mostly due to the calibration of the hobby equipment we’re trying to use now.

To help us better correlate our data, please let us know the following:

- What is the ambient temperature of your testing area (ours is 75 degrees F)?

- What is the percentage of humidity in your testing area (ours is around 30% typically)?

- What is the resting voltage of a 7.4V battery a few minutes after coming off the Hyperion Duo chargers you use to charge (our numbers for one Hyperion Duo unit are posted above)?

Again, our goal is to achieve a standardized test environment, equipment, procedures, etc. so we can label our packs with honest and accurate numbers the way you seem to be now. However, our continued concern is that our proven better performance battery delivers numbers not as good as those you put on the label of a battery that, when tested on the same GFX unit using the same procedures and in the same conditions, does not perform as well.


Also, as we too believe strongly in truth in advertising and published data, do you plan to change the information included on the label on the boxes of your 5000mAh 28C batteries to more accurately reflect your current test equipment and charging procedure? This is how the info reads now:

Quote:
LIGHTNING VOLTS PACK SPEC

Pack is cycled on a Competition Electronics LiPo T35-GFX. Pack is charged at 1C and discharged at 35 amps down to 6.0volts. Measurements are taken through the power leads.
However, as stated above, you are actually charging with a Hyperion Duo charger at a rate of 2C.

As a note, we would have duplicated the equipment and procedure you currently use in our first tests if that was what had been listed on the label on the box. However, we simply followed the info as listed on the labels we have now so we charged at 1C using the same GFX unit we discharged (cycled) on.

Quote:
Originally Posted by Danny/SMC View Post
We do cycle our 28C packs and print the info on the packaging the problem is that were the only one doing it. We can easily change the numbers by hooking up the voltage sensing leads at different places. The pack temperature also has an impact on numbers and then there is the way the pack was charged discharged that impacts the number. This means it would be hard to compare numbers.
Quote:
Originally Posted by Danny/SMC View Post
As you can see there is no real standards of testing and due to all the variables it is to hard to establish one.
If this is true, wouldn’t it be most fair for no one to publish GFX numbers on their batteries and to let customers decide which battery performs best by testing it on their own GFX, other testing equipment and/or on the track? We prefer it not to be the case as consumers want to see the GFX numbers, but, if we cannot achieve the same results you are now, it does not seem like this can be the case as your numbers vary greatly from ours and many others’.

Last edited by Jason/TPRC; 12-02-2008 at 08:37 PM.
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Old 12-02-2008, 08:31 PM   #101
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Originally Posted by trickd122 View Post
Ordered mine today !!! At $99.00 you simply cannot beat that price worse, case scenario even if it turns out to be a 35C pack still, an excellent deal. SMC's 28C is $130!!! Trinity's 3800 35C is $89+
No you didn't!!! hopefully they'll arrive by Friday in time for the Dash Let me know so we don't run on the same heat
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Old 12-02-2008, 08:47 PM   #102
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Jason, any feedback for my questions?

You told me that it is a 2S2P pack, but why the voltage index from the graph show 4.2V and discharge at a capacity of 5.0mAh (Ah). I am geting one of your pack soon and would like to use the same testing method as yours.
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Old 12-02-2008, 08:58 PM   #103
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Jason,
I'm glad you have experience with the GFX.

There can't be be a standard for numbers as this can easily be manipulated. I have been involved in matching cells for 20 years and I have seen it all.

The reason why we post numbers on our packs is that we cycle each pack in house to make sure they meet our minimum specs. When we do the cycling on the packs we decided to post the numbers to show racers what there getting.

As you see your not getting the same numbers as us so it's just a reference point but those are the numbers we got when we cycled the packs. You should also consider how long the packs have been sitting with storage charge as I have noticed that storage charge seems to hurt the capacity a bit. Atleast that is what I see with the packs I have tested.


Feel free to send me your pack that you have numbers on and I will put it on one of our GFXs to compare numbers if you feel it's that important.

As far as our label on the box we were using a 1C charge rate with the GFX and it was taking to long so we bought Duos to speed up the process and make sure our packs are balanced. I tested the difference between 1C and 2C charge rate and it didn't change the numbers. So if I put the pack on the GFX and charge at 1C I will get the same numbers as putting it on the Duo with 2C. Were working on updates on our website and I will post this info.

Since you seem concerned with our numbers and our claims are you going to relabel your pack a 4900 since your getting 4900 out of your pack using a Duo to charge ?

Like I said I'm sure your new packs are good as were well aware of improvements in the Lipo market but to call us out because of numbers on a GFX is kind of aggressive as there are so many variables that it's hard to compare.
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Old 12-02-2008, 09:05 PM   #104
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Quote:
Originally Posted by Jason/TPRC View Post
Here are all the numbers for reference:

SMC 5000mAh 28C 7.4V

Numbers from the box label:

IR = 5.4
Seconds = 537
Avg. Voltage = 7.43V
mAh = 5220

Numbers when charged at 1C on our (best) GFX unit, and discharged on the same GFX unit with the sensing leads attached to the solder joints of the male Deans Ultra Plug connector on the GFX leads:

IR = 6.8
Seconds = 529
Avg. Voltage = 7.38V
mAh = 5143

Numbers when charged at 2C on our Hyperion Duo charger, and discharged with the (best) same GFX unit used for the previous test, with the sensing leads attached to the solder joints of the female Deans Ultra Plug connector on the battery leads:

IR = 6.7
Seconds = 522
Avg. Voltage = 7.36V
mAh = 5075


And for added reference:


Thunder Power 5000mAh Pro Race 40C 7.4V

Numbers when charged at 1C on our (best) GFX unit, and discharged on the same GFX unit with the sensing leads attached to the solder joints of the male Deans Ultra Plug connector on the GFX leads:


IR = 5.7
Seconds = 524
Avg. Voltage = 7.44
mAh = 5094

Numbers when charged at 2C on our Hyperion Duo charger, and discharged with the (best) same GFX unit used for the previous test, with the sensing leads attached to the solder joints of the female Deans Ultra Plug connector on the battery leads:

IR = 5.7
Seconds = 507
Avg. Voltage = 7.44V
mAh = 4929
Ok, I don't claim to know anything about Lipo and C ratings and such so my question might be completely wrong.

The SMC pack you have claims to be a 28C and your pack is claimed to be a 40C but gets lower numbers than those claimed on the 28C battery how do you justify a 40C rating and SMC justify a 28C rating? Is C rating something entirely?
I can understand the ratings you've posted, IR, Run time, V and Mah. Those numbers mean something to me and I'm good with them. I'm glad you have posted them. I just can't see how they relate to C rating and why a higher C rating battery is better.
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Old 12-02-2008, 09:27 PM   #105
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Ok, I don't claim to know anything about Lipo and C ratings and such so my question might be completely wrong.

The SMC pack you have claims to be a 28C and your pack is claimed to be a 40C but gets lower numbers than those claimed on the 28C battery how do you justify a 40C rating and SMC justify a 28C rating? Is C rating something entirely?
I can understand the ratings you've posted, IR, Run time, V and Mah. Those numbers mean something to me and I'm good with them. I'm glad you have posted them. I just can't see how they relate to C rating and why a higher C rating battery is better.
Hey Rob, good question!

As for what I know, the C rating is how much current can be pushed through the battery without taking away from its performance. There is a continuous C rating wich is the base current push and there is the sustain and burst C rating wich is what the battery can take for short periods of time.

I have been testing some 28C, 33C and 35C rated cells lately thinking that the higher C rating batteries would yield higher voltages and lower IR's, but this does not seem to be the case. Actually I have found out that the 28C packs have the best overall performance and performed better than the 33 and 35C packs.

Im not dissin on these packs because I like to see the advancement in technology as most anyone would. I think the #'s that all of are used to (Ir's, voltage, runtime, etc) have the most importance for RC racing. I also agree with Jason about the variences in equiptment and unit to unit as this is the same thing we have seen, we have used multiple GFX's and each one yields different #'s.

I think that on track performance of any pack is going to produce the best hype!

Damon
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