Batteries: Which Lithium Chemistry and How Are You Charging?

[Notorious B.E.N.]

On my last gasser, I was running Fromeco Iron Corps which I later updated to some Hyperion LiFe packs to go with a redundant battery system for the RX. With the 2 CellPro charges I had at that time, I could have everything fully charged in 30 minutes and of course the few times I needed to recharge at the field wasn't a problem.

I just sold my 89" Slick and I was running Fromeco Relions with their switch and regulator and the only issue I had was the charge time. I used to have 2 chargers that I didn't need to plug in a balance tap (all but 1 charger are CellPro) and now that I'm down to 1, it takes a good 1.5-2.5 hours to charge the batteries since I only charge at 0.5-1C.

I ordered an EF 88" Edge to replace the Slick and since my Relions are almost 3 years old, I'm thinking about changing set ups.

I might stick with Relions or go to LiPo packs so that I can parallel charge and charge with my 3 CellPro charges but of course the Relions have a lot of density for the weight and have always been reliable.

So, what chemistry (LiFe, LiPo, LiIon) are you using and what's your charging set up?

 

[jamesrxx951]

I have a set of Fromeco A123 packs in my 35%H9 300 and using the new Thunder Power Lipo's with the JXT connectors in both my 40% IMAC birds. I have used Pulse and still using them but after noticing a drop in voltage during snaps I felt that the low C rating of the Pulse may be a factor. So im giving the Thunder powers a try that are rated for 25C. They seem to be doing very well. The price on the TP's have come down and pretty reasonable IMHO.

 

[Bbcorvette18]

Powersafe rx, 2s lipos I can fly 3 flights and have complete redundancy then pull the canopy switch out my $20 worth of batteries and keep flying while I charge the other packs.

 

[ChickenBalls]

2S lipos cheap, simple, and easy. works for me

 

[Judge]

I'm using Pulse 2,550 mAh lipos in my 50cc Extra. I use two packs through two switches into the RX. These are either 15C or 25C cells. At 15C they will deliver full voltage at up to 38 load. Since parallel packs halve the load I can actually pull 76 amps with no issues. I sincerely doubt that people are seeing a significant voltage depression with a 15C cell.

I know we all think our planes are pulling 200 amps and hence need all kinds of exotic devices and huge packs to deal with that, but the actual truth is that even a large 40% plane is only going to pull around 5 to 6 amps average with spikes up to 30 amps or so. Emcotec wired up a 40% plane a few years ago and measured a 4 amp average with 25 amp spikes in consecutive snaps.

I'd look at wiring and switches before I suspected low C rating packs as the culprit for lowered voltages.

I charge mine using either a Hyperion DUO or a iCharge 106B+. I NEVER charge over 1C. In fact, I rarely charge at the field, and again, when I do, 1C is the max.

 

[ChickenBalls]

I'm using Pulse 2,550 mAh lipos in my 50cc Extra. I use two packs through two switches into the RX. These are either 15C or 25C cells. At 15C they will deliver full voltage at up to 38 load. Since parallel packs halve the load I can actually pull 76 amps with no issues. I sincerely doubt that people are seeing a significant voltage depression with a 15C cell.

I know we all think our planes are pulling 200 amps and hence need all kinds of exotic devices and huge packs to deal with that, but the actual truth is that even a large 40% plane is only going to pull around 5 to 6 amps average with spikes up to 30 amps or so. Emcotec wired up a 40% plane a few years ago and measured a 4 amp average with 25 amp spikes in consecutive snaps.

I'd look at wiring and switches before I suspected low C rating packs as the culprit for lowered voltages.

I charge mine using either a Hyperion DUO or a iCharge 106B+. I NEVER charge over 1C. In fact, I rarely charge at the field, and again, when I do, 1C is the max.

Sounds bout right, I'm using wolverine switches on redundant 2s lipos Glacier 2600, and just purchased a couple of the pulse 2550 packs. no voltage sag at all. I'm using the A9 and can see any sag in voltage

 

[Notorious B.E.N.]

Yeah, the servos don't pull enough to need high C packs. I'm sure even the 10C multirotor packs can provide enough flow.

 

[jamesrxx951]

I'm using Pulse 2,550 mAh lipos in my 50cc Extra. I use two packs through two switches into the RX. These are either 15C or 25C cells. At 15C they will deliver full voltage at up to 38 load. Since parallel packs halve the load I can actually pull 76 amps with no issues. I sincerely doubt that people are seeing a significant voltage depression with a 15C cell.

I know we all think our planes are pulling 200 amps and hence need all kinds of exotic devices and huge packs to deal with that, but the actual truth is that even a large 40% plane is only going to pull around 5 to 6 amps average with spikes up to 30 amps or so. Emcotec wired up a 40% plane a few years ago and measured a 4 amp average with 25 amp spikes in consecutive snaps.

I'd look at wiring and switches before I suspected low C rating packs as the culprit for lowered voltages.

I charge mine using either a Hyperion DUO or a iCharge 106B+. I NEVER charge over 1C. In fact, I rarely charge at the field, and again, when I do, 1C is the max.

FYI the pulse reciever packs are rated for 6 Chttp://www.pulsebattery.com/batteries/pulse-ultra/plurx-25502-pulse-lipo-2550mah-7-4v-rx-ultra-power-series.html according to the note.

On my 3.1M H9 Sukhoi running a JR power bus reciever I would record up to a 1.5v drop in volage during a snap. Fromeco LiIons were a little higher.

 

[Judge]

The packs I am using are rated at 1C charge and 15C discharge. See the attached image I just snagged off the pulse site.

 

[jamesrxx951]

The packs I am using are rated at 1C charge and 15C discharge. See the attached image I just snagged off the pulse site.

That is the link I provided. The 6C receiver pack may be for battery charger discharge only but on the first few flights on a fresh charge I could tell a slight difference in snaps only. Once the initial peak voltage wore off it was even throughout the flight. In fact the lowest recorded voltage seemed to hold steady also. The voltage drop really was not linear.