6.6V 2S receiver LiFe battery packs

[KRProton]

Here are some viable LiFe receiver packs. The Zippy is the smallest, but hard to come by. Looks like it’s been discontinued, but replaced by another Zippy, but seems they’re usually not in stock at HobbyKing. Looks like the Venom 850 has been discontinued too, but I left it in the photo for size comparison. I still have a few of those in my rotation. The Spektrum looks like an awesome choice, but I install my battery packs in the nose of my Q40s, so the length makes it a tight squeeze. I think it was Dan Kane who recently told me about the Fantom. It’s virtually the same dimensional size as the Zippy. It has two discharge leads and the balance lead is quite short.

Zippy 700mAh https://hobbyking.com/en_us/zippy-fligh ... -pack.html

New Zippy 700mAh https://hobbyking.com/en_us/zippy-compa ... -pack.html

Fantom 900mAh https://fantomracing.com/shop/batteries ... iver-pack/

Venom 850 Discontinued

Spektrum 900mAh https://www.spektrumrc.com/product/6.6v ... 0LFRX.html

Tim Lampe

[KRProton]

Here's another LiFe pack that Dan Kane told me about. It's a 500mAh available from amain hobbies...

https://www.amainhobbies.com/protek-rc- ... 83/p177906

Tim

[delateurj]

I have used the protek one on many planes with no problem...although they don't like hitting the ground above 100 mph.

I always cycled them as recommended by Amain Hobbies before use, from the website:
NOTE: Brand new LiFePO4 batteries have been found to fail prematurely if they are deep discharged below 33% capacity too early. A break-in period of 20 cycles is currently recommended. While testing has shown that this battery can be charged at up to 3C rates, it is recommended that this battery not be charged at rates higher than 1C to maximize the lifespan of the battery. Additionally, LiFe batteries should not be discharged below 2.5V per cell to avoid pre-mature failure and maximize battery life span.

[Sparky]

Based on 7 flight/races at around 50 MAH per flight I would be a bit concerned about flying the day without a charge. I have the 700 and 1100 zippys and satisfied with the performance. They are the no brainier part of racing that used to be some concern.
I had never heard (or done) about the cycling regimen suggested above.
Sparky

[stoned]

I am using the venom 430 mil lipo pack in all of my q40's.I average less than 20 mil a flight. I do cycle a new battery 4 or 5 times before I use it.

[Sparky]

Dean you said Lipo battery which is higher voltage, good to know.
I believe we are talking about LiFe/A123 chemistry batteries.
OK what is the V/cell you discharge to and load when you cycle the packs?
Sparky

[stoned]

I charge a new pack then discharge half of the capacity. I discharge the 430 pack about 200 mils then charge it again. I write down what I put back in it then discharge it again. I repeat this process until I put in what I take out . It takes several cycles to get the battery to full capacity. I never charge or discharge more than 1c.

[rocket]

Lipo fully charged is 8.4 volts. Non HV servos dont like this. A little battery management like charging a lipo to the max voltage of a fully charged life pack and your servos will be fine. If you have ever played with this you'll see that a 700 mah lipo charged to 7.5v will sit at 7.4 for days where a fully charged 700 life pack will need to be charged again. Plus the lipo will in most cases have a higher C rating than a life pack.

[DHG]

I luv luv luv the ProTek 500s. I used to follow the break-in instructions religiously, then a very wise person who shall remain nameless but whose initials are Lonnie Finch said "or you could just use them." At 30-40 mAh per flight, a normal day of test flying takes them down to maybe 60%. Go home, charge at 1C, fly the same way next time out, rinse and repeat. By the time race day comes, they'll have 5-10 gentle cycles on them and if you're the least bit nervous, pump them up a little over lunch hour. They're also light enough that if you don't have room to put them in the nose, it won't affect the CG enough to matter.

Cheers,
Duane (the slow one)

[rocket]

Have a dozen of them. Great little life pack.

[KRProton]

I luv luv luv the ProTek 500s. I used to follow the break-in instructions religiously, then a very wise person who shall remain nameless but whose initials are Lonnie Finch said "or you could just use them." At 30-40 mAh per flight, a normal day of test flying takes them down to maybe 60%. Go home, charge at 1C, fly the same way next time out, rinse and repeat. By the time race day comes, they'll have 5-10 gentle cycles on them and if you're the least bit nervous, pump them up a little over lunch hour. They're also light enough that if you don't have room to put them in the nose, it won't affect the CG enough to matter.

Cheers,
Duane (the slow one)

Yea, at the current load and discharge rate that our rx packs are subjected to, the way we are using them basically is gentle cycling.

Tim

[rocket]

And this...

[KRProton]

And this...

I have one of those in one of my Quickies.

Tim

[DHG]

The Spektrum 300s are probably fine for all our racing planes as long as you don't have a stalled servo. I have one in my DLG (yes, I'm glider-curious) and have flown literally all day on a charge. FWIW, a stalled servo will put you down pretty fast. The nosewheel retract servo on my Super Kaos (yes, I'm also pattern-curious) sucked 60% out of my new Venom 850 on one flight when the steering cable snagged the strut. That was only one landing approach plus about 10 minutes of troubleshooting. The good news is those digital servos can take a licking and keep on ticking!

Cheers,
DHG

[DT]

Guys, I’m flying the Zippy 700’s what should I set my low voltage warning alarm at?