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Old 07-17-2014, 06:57 AM   #121
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I have used the IP 7600's and 6000mah all year, changed to the 6000's for better balance but all are still perfectly flat
Over 3/4 of the packs that have passed through the discharge bucket at WLRC (before I put them in the recycling at work) have been IP's, all different capacities.

When friends have asked me to check their lipo internal resistances on my meter, the Ip's always come out worst.
Their price is the only plus point

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Old 07-17-2014, 09:07 AM   #122
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They still test out well on my ESR lipo meter
What are the results and how do different packs compare.
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Old 07-17-2014, 09:54 AM   #123
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What are the results and how do different packs compare.
Most give me 3-4milliohms per cell.
My best is my THunder Power 6000, 2.96, my worst is one of the my old TP 6000 (at least 3 years old and thrashed) 7-9milliohms per cell.


Friends ORCA's etc typcally give 3-4mOhms per cell as well, but not sure if they don't tail off after a few months.

I know someone who did a lot of research on chargers and how accurate their internal resistance reading were and found the only decent chargers were decent Hyperion units.
Still don't fully understand how a charger can accurately give you internal resistance whilst it's charging
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Old 07-17-2014, 01:33 PM   #124
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Originally Posted by Skiddins View Post
Most give me 3-4milliohms per cell.
My best is my THunder Power 6000, 2.96, my worst is one of the my old TP 6000 (at least 3 years old and thrashed) 7-9milliohms per cell.


Friends ORCA's etc typcally give 3-4mOhms per cell as well, but not sure if they don't tail off after a few months.

I know someone who did a lot of research on chargers and how accurate their internal resistance reading were and found the only decent chargers were decent Hyperion units.
Still don't fully understand how a charger can accurately give you internal resistance whilst it's charging
I've found the ESR meter to be useless here. It varies too much based on pack charge. All of them have to have the same amount of charge or it will affect the readings.

The only thing I've found to give proper IR readings is a GFX or the I charger 4010, 308 or 406. This is when comparing them to a 4000.00 fluke isolation meter used to tet resistance in real electric vehicle batteries.

The GFX and Icharger do not take readings as the battery is charging. The GFX stops it for 2 seconds at 123 seconds into the charge to check it. Tha icharge takes it while it appears the battery is charging but it pauses for a brief second to check it and will update it all throughout the charge. And you can also check it while the battery is just sitting as well without charging it at all.

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Old 07-17-2014, 05:04 PM   #125
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Most give me 3-4milliohms per cell.
My best is my THunder Power 6000, 2.96, my worst is one of the my old TP 6000 (at least 3 years old and thrashed) 7-9milliohms per cell.

Friends ORCA's etc typcally give 3-4mOhms per cell as well, but not sure if they don't tail off after a few months.
Thank you for posting the result the TP packs are certainly one of the best.

Cell temp and state of charge has a noticeable effect on the results.

Using my icharger the 7200mAh 80C IP pack that has over 200 cycles now had about 1.5mOhm per cell when new (depending on temp) and produced near identicle results below 2mohm after 150 cycles.

I have had an older IP pack (about 2 years old at least 500 cycles) that I did comparison tests with earlier this year cant remember the C rating that was below 5mOhm per cell.

I also tested one pack of the Orion 90Cs that a lot of local racers rave about using the same charger and they were about 3.5mohm.

Maybe my charger provides lower IR readings than your but at least with comparisons of different packs we might be able to draw some conclusions.

Which ORCA's were they?
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Old 07-17-2014, 05:09 PM   #126
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Would be worth checking out this thread and the results posted.

http://www.rctech.net/forum/electric...d-results.html


https://www.youtube.com/watch?v=waBmuiv8v9g

https://www.youtube.com/watch?v=5qXbWNRjWGQ
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Old 07-26-2014, 05:40 PM   #127
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Originally Posted by frozenpod View Post

Which ORCA's were they?
6200, the 7500's are too heavy to get their cars balanced.
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Old 07-27-2014, 12:55 PM   #128
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I've found the ESR meter to be useless here. It varies too much based on pack charge. All of them have to have the same amount of charge or it will affect the readings.

The only thing I've found to give proper IR readings is a GFX or the I charger 4010, 308 or 406. This is when comparing them to a 4000.00 fluke isolation meter used to tet resistance in real electric vehicle batteries.

The GFX and Icharger do not take readings as the battery is charging. The GFX stops it for 2 seconds at 123 seconds into the charge to check it. Tha icharge takes it while it appears the battery is charging but it pauses for a brief second to check it and will update it all throughout the charge. And you can also check it while the battery is just sitting as well without charging it at all.

EA

100% agree...

The I charger is the way to go!!

I look at more towards how long the voltage stays up in the pack and compare that to other lipos..

Voltage is speed after all!
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Old 07-27-2014, 02:24 PM   #129
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How about the Zombie, eg: 6200
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Old 07-28-2014, 04:53 PM   #130
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6200, the 7500's are too heavy to get their cars balanced.
I have about 30 cycles on the IP 6000mah 90C/Orca 6200mah 90C.

So far so good.
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Old 07-28-2014, 05:20 PM   #131
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The Ultimate battery for 17.5t blinky would be any low IR lipo pack with a supercapacitor attached to the ESC battery connector... Think about. The esc has capacitors, the Rx has a glitch capacitor, so why not the battery ??? The voltage sags will be eliminated, and the current draw will decrease. More punch, more battery voltage at the end of the run, etc....

Last edited by bertrandsv87; 07-28-2014 at 05:37 PM.
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Old 07-28-2014, 06:10 PM   #132
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The current lipos are excellent but the next evolution for RC might be the new super caps (currently under development). They can be charged in seconds and have well over 10,000 of cycles.

The current readily available high capacity super capacitors have a lower energy density and similar IR of the current lipos. Not a huge amount to gain by using them.
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Old 07-28-2014, 06:17 PM   #133
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The current lipos are excellent but the next evolution for RC might be the new super caps (currently under development). They can be charged in seconds and have well over 10,000 of cycles.

The current readily available high capacity super capacitors have a lower energy density and similar IR of the current lipos. Not a huge amount to gain by using them.
Weight and size? specs or links? please
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Old 07-28-2014, 07:58 PM   #134
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There are a number of papers that have been published from monash university.

There is an article about them here

http://siliconangle.com/blog/2013/08...cid-batteries/
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Old 07-28-2014, 08:06 PM   #135
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There are a number of papers that have been published from monash university.

There is an article about them here

http://siliconangle.com/blog/2013/08...cid-batteries/
that would be very neat to see a battery that can be used in our cars like that. I bet theyd be SUPER light. Like 100 grams if that, and would last the entire race and be much smaller than the traditional stick lipo. Which would allow for radically new chassis lay outs! Or we could put them on our esc... and replace the standard caps
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