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Old 05-05-2011, 11:16 AM   #16
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I just purchased the Hobbico pack and I noticed something slightly concerning. It's officially rated at 1C (so 1.3 amps) yet will be required to push around 5 amps quite often during a run. I ran a couple of tests and after 5 cycles it dips down to 5.5v under a 4 amp load.

What voltage does the Hyperion or Protek packs deliver at 3C?
what are you using with??? i never once had mine even drop under 6V after a hour+ of use.....i just charged and ran them in my buggy/truggy and like i said, never once dropped under 6V, even after 3 quals and a 30 min main on one charge...
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Old 05-05-2011, 02:26 PM   #17
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I'm not speaking about the final resting voltage which is properly 6.6V, but instead the voltage under load.

I took a few pictures to demonstrate. I set my charger to discharge at 5amps with a cutoff of 5.5V. The charger slowly ramps up from 0 to 5 ohms as a safety measure. At half an amp the voltage is 6.48. At 2 amps it is at 6.00 volts. By the time it reaches 3.84 amps the battery is down to 5.51 volts. This charger has 35 watts of headroom but stops well short (21 watts). When I switch back to charging the battery (at rest) is 6.6 volts as you would expect.

While thinking about the loss, the main variables are internal resistance, wire gauge, and the JST connector. The wire appears to be 18 gauge while the JST connector is capable of 10 amps. The most likely suspect here is the internal resistance which is corroborated by the 1C discharge rating.

The 1700mah Hyperion I bought last year had a 5C rating but died on the first discharge as one of the parallel cells wouldn't take a charge. I imagine the Intellect / Protek pack has a similar rating. Could anybody with either of these batteries do a similar measurement?





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Old 05-05-2011, 03:48 PM   #18
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FWIW, at 5 amps the battery puts out 5.39 volts.
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Old 05-05-2011, 03:55 PM   #19
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I think your digging a bit too deep into things. One of the great characterics of life batteries is the number of cycles they have over he useful life of the battery. Just charge it up per the manufactures instructions and run it.
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Old 05-05-2011, 04:03 PM   #20
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Hey, I love LiFe batteries and have been running them for 2 years. I only got concerned with this particular battery since it says 1C on the label. And dropping down to 5.5v under load negates a lot of the performance when using LiFe.
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Old 05-05-2011, 05:04 PM   #21
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Interesting, What radio out of curiosity ?
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Old 05-06-2011, 12:50 AM   #22
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I had a 1700 hyperion and it was good for just over an hour in a truggy running 2 15kg aces, the thicker gauge wire and bigger plug still didn't look up to handling the 5C charge so I stuck with 2C
I have no idea what the max discharge would have been when both servos were working there hardest together but i wouldn't think its anywhere near 5 amps?
If you had 2 30kg servos and put them under full load how many amps would they be sucking.

I know that if a LiFe goes a bit puffed they loose alot of capacity and will dump on you even in a 30 minute main

Do you guys balance your packs every time?
does it improve life and run time?
My battery supplier says the main killer these types of pack is running them too low.
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Old 05-06-2011, 01:19 AM   #23
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Originally Posted by mthird View Post
I just purchased the Hobbico pack and I noticed something slightly concerning. It's officially rated at 1C (so 1.3 amps) yet will be required to push around 5 amps quite often during a run. I ran a couple of tests and after 5 cycles it dips down to 5.5v under a 4 amp load.

What voltage does the Hyperion or Protek packs deliver at 3C?
what will draw 5A constant in your buggy or truggy?

Even with 2 servos stalled out you would be hard pressed to get 4.5A and you sill never stall out 2 servos running your car
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Old 05-06-2011, 06:52 AM   #24
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I have no hard data on the average and max draw is on two high speed/torque servos are. I have heard that a 3amp BEC is not enough on the electrical side of the house and that most ESC's now include a 5 amp BEC.

I'll happily use this pack as it has kept it's shape after 5 duty cycles unlike the H-Energy packs that puffed after 1.
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Old 05-06-2011, 07:09 PM   #25
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I'll happily use this pack as it has kept it's shape after 5 duty cycles unlike the H-Energy packs that puffed after 1.[/QUOTE]


+1 F... H-Energy, Angelo, and Cobra Racing with their $hitty LIFE packs. You sell junk just be man enough to say it.
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Old 05-06-2011, 07:32 PM   #26
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$130 in packs (including shipping) and unfortunately I have to agree. At the time I ordered them they were the only pack that fit the OD battery box.
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Old 05-07-2011, 04:01 AM   #27
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$130 in packs (including shipping) and unfortunately I have to agree. At the time I ordered them they were the only pack that fit the OD battery box.
yeah I had the same problem. they were the only pack that would fit in my 8ight with the flat battery lid. I had 3 and they all puffed. I died mid run and caused a runaway.....

anyway angelo did replace one but it puffed as well. not great cells.

my experience with the protek (are they IP?) packs have been good. been running themin the mugen for 4 months now and only on sunday in a 60 min main in thailand did one slightly puff. still charged ok but I dont trust them once they have puffed a little.
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