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Feb 13, 2016, 10:28 PM
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now, hear this:


just for the kicks:

http://cleantechnica.com/2016/02/12/...edaf-332107717
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Feb 13, 2016, 10:31 PM
Registered User
Got a friend who bought two 5000mah Graphene hard case for his traxxas. Both batteries hit lvc after only 5-6 minutes from bad voltage sag. It's supposed to be I think a 90C battery, for his 4x4 vxl. When he puts the pack onto the charger after the lvc run it still says 3.9-ish volts on the cells. He said the highest IR cells are around 6. So it's more like a 15C and is unable to provide the amps needed.
Feb 13, 2016, 10:32 PM
Registered User

4S 1300mAh Graphene on 210 racing quad


Got a few decent passes in today with my friends and took a minute to capture a couple on radar. The Graphene's do indeed 'fly heavier' than other 4S 1300's that weigh ~20 grams less but the Graphene's have a speed advantage due to their lower internal resistance and higher loaded voltage.

Will pop up a short video clip in the next day or so.

My minor nits with the 65C 1300's -
  1. Main output leads are longer than I desire. I'll likely shorten them by a inch or two at some point. The XT60's will get replaced with my beloved APP's if I happen to do this.
  2. Balance tap leads are longer than I desire. These need to be tucked away and secured when flying in a mini quad to avoid becoming prop fodder. Much more difficult to shorten these by the end user so I will leave them alone.
  3. Pack weights are higher than I desire. Such is the nature of the beast though as these packs just plain deliver the goods. For more tame flying where ultimate power is not necessarily needed, lighter packs may work better (horses for courses).
On the whole, I'm quite pleased with my 4S 1300's and will be thrilled if mine last anywhere near as long as Rick's. Have had the packs in heavy rotation and have been field charging as soon as I land. This allows me to stay in the air until my field battery goes kaput. At ~3 minutes per flight, field charging is a necessity.

Mark
Feb 13, 2016, 10:53 PM
Registered User

for all that i see...


1.-considering that some are running the graphenes to the limit and beyond, and for what i see, not using telemetry to tell volts, am surprised that you guys are not using at least a simple device to give you a warning.
something like this;
https://www.hobbyking.com/hobbyking/s...15Mhz_FM_.html
compact, light, and affordable.

2.-and why are comparing packs of same advertized capacity if the weights of the graphene are higher. a 1300 graphene weighs about the same as a whatever 1500, so those should be compared.
not gr 1500 vs whatever 1500.
now, don't start throwing stones. just think about this.
Feb 13, 2016, 10:57 PM
Registered User
Quote:
Originally Posted by LVNeptune
Just ran through all 10 of my 1000 4S batts. Not impressed. Noticeable punch loss because of extra weight. They lasted roughly 1.5-2 minutes on a 210 running LB20's and Cobra 2204-2300kv's w/ DAL 5045BN 's.

Will be selling them off. Maybe the 1300+ are better but not impressed. They all came down hot. I had FastGixxer fly one as well and he noticed sag within 60 seconds.
How many amps do your 2204 2300kv Cobras pull with 5045 bn on 4s? Mine pull over 13A apiece on 3s. 55 total, peak, and that's with 1800mah 65c. Dare I suggest that even with 65c, you are wrecking those 1000mah batteries? No wonder they come down hot. You may argue that other packs can do it, maybe so, but they won't last anywhere near as long as these are quoted to do. Seems very many people are quite pleased with them, except the ones who expect double the quoted discharge rate, which again, are typically overrated anyway.
Feb 13, 2016, 11:08 PM
Registered User
Quote:
Originally Posted by phil alvirez

2.-and why are comparing packs of same advertized capacity if the weights of the graphene are higher. a 1300 graphene weighs about the same as a whatever 1500, so those should be compared.
not gr 1500 vs whatever 1500.
now, don't start throwing stones. just think about this.
As far as I can tell that's exactly what is happening -- most everyone is comparing the 1300 vs. 1500 or 1000 vs. 1300
Feb 13, 2016, 11:15 PM
Registered User
Quote:
Originally Posted by RustySpork
How many amps do your 2204 2300kv Cobras pull with 5045 bn on 4s? Mine pull over 13A apiece on 3s. 55 total, peak, and that's with 1800mah 65c. Dare I suggest that even with 65c, you are wrecking those 1000mah batteries? No wonder they come down hot. You may argue that other packs can do it, maybe so, but they won't last anywhere near as long as these are quoted to do. Seems very many people are quite pleased with them, except the ones who expect double the quoted discharge rate, which again, are typically overrated anyway.
+1 you cant run a 1000mah lipo at 70+C discharge (even in short bursts) and then complain about heat or short flights etc.. I'd like to know which other 1000mah packs do work in that application.
Feb 13, 2016, 11:27 PM
AMA 1051390
My dinogy and LiHV actually hold up well both 1000's
Feb 14, 2016, 12:50 AM
Registered User
24 bucks for a dinogy, 18 for a comparable graphene. 1000 mah 4s 65c. 33% premium. I've read reviews, never used a dinogy myself, but I'm sure you get what you pay for. But just because they "hold up well" doesn't mean you aren't abusing the battery. Tell me how well they're holding up in 100 cycles. If they are, you definitely got what you paid for.

Also, just because you can do it with an extremely high quality lipo doesn't mean you can get away with it with any lipo. The point is, how many times are we going to hear the same line, "these 1000mah batteries are crap, they can't even handle 60-70-80 amps without sagging and getting hot"?
Feb 14, 2016, 12:52 AM
AMA 1051390
Truthfully I got them because they are lighter nothing more. I am going to get 1300's and maybe 1500's I think these 1000's will be great on light X frames like my Arc200 or Shrike though.
Feb 14, 2016, 02:38 AM
Registered User
Quote:
Originally Posted by nighthawk0077
+1 you cant run a 1000mah lipo at 70+C discharge (even in short bursts) and then complain about heat or short flights etc.. I'd like to know which other 1000mah packs do work in that application.
The Turnigy Bolt HV 4s 1300mah 65c seem to keep up with the Graphene.
Feb 14, 2016, 02:42 AM
Frankenstein recycled packs
rampman's Avatar
Thread OP
Quote:
Originally Posted by LVNeptune
mohms?
Just fine.
The pack had to sit all day, 12 hours, at an overdischarged state. Family...

The weekest cell is still showing 25C and good for 33 amps BUT the pack temp was only 67F. I am sure this will go up by at least 1C when the pack temp is closer to 72F and sitting at a full charge.

Rick
Feb 14, 2016, 03:50 AM
Registered User
We need to stop comparing whatever is labeled on the package, and start comparing what the facts tell us: Weight. Cost. Watt-hours delivered.

Let's compare a 150 gram lipo that costs $30 and lasts 3 minutes, to another lipo that weighs the same or costs the same or last the same amount of time. Figure out what you want to optimize for, and optimize for that.

If you are running a tight quad racetrack that only takes 2 minutes to run your laps, and you don't care about price but weight is critical well then let's find the best lipo for that. If you need a lipo that can burst your glider up to height then cutoff and be light for finding thermals, well find the best for that. If you want to have a super cheap lipo to buzz around your neighborhood and scare stray cats, well optimize for that. If you want a battery that can take a million charge-discharge cycles so you never have to buy another, then go for it.

Be reasonable. An honest 65c lipo drains in 55 seconds. A 130c burst drains in 27 seconds. What's a burst, 10 seconds? Recovery of 10 seconds before another burst means full drain in 68 seconds and that's absurd to expect. If you can get 2 full throttle minutes out a lipo and have it not puff or catch fire that's pretty dern good. And that's only 30c honest.

How fun is flying for only 2 minutes at a time? Size appropriately.

Let's keep supporting cutting edge technology, the market will drive better lipos. Longer fly, higher amp delivery, lighter weight. This is an incremental improvement, and at a very reasonable price.
Feb 14, 2016, 05:33 AM
"An occasional user"
Quote:
Originally Posted by rampman
Just fine.
The pack had to sit all day, 12 hours, at an overdischarged state. Family...

The weekest cell is still showing 25C and good for 33 amps BUT the pack temp was only 67F. I am sure this will go up by at least 1C when the pack temp is closer to 72F and sitting at a full charge.

Rick
How do you measure the "C-rating" in your tests? By measuring IR and putting the values to jj604 calc?
Feb 14, 2016, 06:28 AM
Registered User
Quote:
Originally Posted by downloader9
The Turnigy Bolt HV 4s 1300mah 65c seem to keep up with the Graphene.
That may very well be, but I still wouldn't put 80amp loads through one. In my testing that would bring the cells dangerously low even at full capacity.


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