kenair

My Feedback: (10)

Hi, have a question for warbird flyers as you guys are the most practical (no BS).
Are you using LiFe RX packs in the parallel set up shown by Red's Battery Clinic [link]http://www.hangtimes.com/parallel_packs.html[/link]

do you charge both LIFE packs at the same time??

Feed back appreciated, I've been using NIcad R/X packs in the parallel setup but am thinking of using HK LIFE packs.
.

irocbsa

My Feedback: (12)

I charge all of my LiFe packs individually. You have to do that if you balance charge them, which you should do frequently anyway.

Of course, I have to do it this way because I only have a single output charger. I need to get a newer four output charger so I can charge the whole plane at the same time (2 receiver packs and 1 ignition pack).

wphilb

My Feedback: (10)

I have been using the NoBS setup for some time now, switched over to LiFe packs 2 years? ago and continued using the same setup. I balance charge each pack using a Cellpro charger but only 1 at a time, have never tried to charge both at the same time.

BTW, while saying nothing negative about HK batteries, I have had, and my friends have had, issues with less expensive battery packs so now I buy only SR or NoBS packs. Don't listen to opinions, do the experiment yourself, buy one of each and dissassemble and check the quality of the construction, welds, wires, connectors etc.

Whit

OVSS Boss

As above, I charge each pack seperate, and I am not sure that you could even charge them together on any charger that was worth it's salt. I like to connect the taps everytime, I can see each cell, and know my voltages, it is just a safer way to me.

Marc

Edwin

My Feedback: (2)

I have seen a planes wire harness catch fire when trying to charge two batteries at once. Something to do with a common ground. The owner was there and was able to unplug everything before serious damage was done. However, it took out a smartfly power board. I've also had the same problem but was using the hobbico elite charger, at a much lower charge current and it just errored out on me, I was lucky. Since then, I started wiring my own power switch wiring harness that isolates the ground and hot side of the battery so I can charge both or all three batteries at once.
Edwin

Chris Nicastro

My Feedback: (3)

A) never charge your packs in any RC vehicle.
B) always charge LiFe packs at the standard 1C rate unless otherwise stated by the manufacturer.
C) 20-24AWG servo wire can only handle 4-5A before they begin to fail
D) charging packs in parallel at 1C doubles the charge rate so a 1200mah pack becomes a 2400mah pack and requires 2.4A instead of 1.2A. A larger pack like 3000mah will jump to 6A and so on which could explain the fried wires and circuit.
E) LiPo and LiFe packs do not require to be constantly balance charged. Watch the cell voltages and if the difference is less than 0.15 then dont worry about it.
F) do not inspect packs by tearing them apart. You risk puncturing them or causing the seal at the tab to fail. If the pack is exposed to air its possible it will cause a chemical reaction and a fire

I could go on but read the directions and ask questions and if its not making sense then slow down and think it through.

wphilb

My Feedback: (10)

I will yield to someone with more knowledge of chemistry than myself, but I have been able to partially dissasemble battery packs of all types (often just removing the external shrink-wrap) to compare brands. It's not necessary to dissconnect any welds or wires to determine the difference between a HQ pack and one useful as a paperweight.

I can usually tell just by that step whether the battery was of unacceptable quality. I also usually did this with batteries that I was no longer intending on using, or had bought one of for the sacrifical experiment. For me it's well worth it when you consider the all up cost of a GS plane, and the risk to life, limb and property when one goes airborne.

Determining the quality of the cells themselves is done (by me) through use and charge / discharge monitoring and tracking over time but that is not helpful for a newly bought pack in front of me so I stick to well known manufacturers like SR and NoBS and allow them to select the correct cells for me.

Whit