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-   -   LIFE battery charging in the plane question (http://www.rcuniverse.com/forum/batteries-chargers-84/11330830-life-battery-charging-plane-question.html)

racelikustolit3k 12-14-2012 02:28 PM

RE: LIFE battery charging in the plane question
 
example.. I rebuilt a gp cap 580 and ran one 7955 on the rudder.. well the carbon push rod broke on a snap roll and the rudder servo was at full lock with the rudder flopping.. my aurora 9 tx alarmed ( meaning low voltage ) I looked down and sure enough it was 5.1 volts.. this was a fresh off the charger 6v nimh ( 2 of them actually) and with-in 30 seconds the plane was gone out of sight and into the woods.. we pulled the plane out of the tree it was in and check everything.. it had actually pulled so many amps it melted all the silcon off the servo wires and killed the shrink wrap on both backs.. and melted all the connections together.. undid all the batts and switches and pluged in a new batt straight to the rx and everything came back to life..

same thing happened on a 43% edge ( USING HOBBICO LIFE PACKS NOW ) 1 of the 3 rudder servos let go and I got a real mushy rudder ( 2 working servos fighting one locked up servo ).. landed and the servo was smokin like crazy I popped the canopy, reached down and clipped the wires and the plane went back to completely normal.. so I shut everything down and charged the batts they were about 70% drained and hotter than hell but I got my 5500$ plane back in one piece..

they are well worth the money if you fly GS planes

choihjin 12-14-2012 02:40 PM

RE: LIFE battery charging in the plane question
 
Quote:

ORIGINAL: raron455

Hello, after all the advice I got on my post for battery help, I was convinced that my ni-mh days are over and it was time to run the life (A123) batteries,,SO I went out and bought a hobbico life 6.6 2100 mah battery. I
Iike the shape of it and mounting it is really easy. I have a hitec x1 charger that can balance charge this life battery, as the one thing I am certain is the battery needs to be balance charged every time, so My charger is more than capable of this, the battery has two connectors that can go into recievers,etc, one large deans connector, and the balance connector,, BUT HERE IS THE PROBLEM, once the battery is in the plane,, how the heck do you balance charge it,, I have one of the power switches with the charge port (SEE PIC) I have these switches in all my planes,, so to balance charge the life battery I will have to remove it every time?? this cant be , is there something I am missing? I have searched and am still confused,, any help would be appreciated,
I wish to have a balance charger like this for LiFe, then we can charge LiFe through the balance jack; Hobbyking DC-4S Balance Charger & Cell Checker 30w 2s~4s, which is for LiPo only.

lopflyers 12-14-2012 02:43 PM

RE: LIFE battery charging in the plane question
 
I just lost a plane due a Nimh that was bad, it was less than a yr old. I'm switching slowly yi LiFe

Giant_Scale_Gasser 12-14-2012 03:49 PM

RE: LIFE battery charging in the plane question
 
I run LiFe packs in 11 airplanes I fly from a 100cc Extra to my 54" Skyraider II Club 40 pylon planes.
Some planes I run dual packs, others single. On the ones I have the batteries buried I just add the balance connector extensions and Deans extensions and run them to an easy spot to access for charging.

Never had an issue or even heard of an issue with LiFe packs in terms of danger during charging like a Li-Po. And the safety aspect of the LiFe is why ALL my planes have them now. Only 1 plane in my whole fleet has a Li-Po and that is a tiny 2S on my 30cc Mx2 on the DLA ignition. But it is fully removeable for charging. I DONOT trust Li-Pos.

GRandolph 12-14-2012 04:04 PM

RE: LIFE battery charging in the plane question
 
I charge mi Life battery in my plane. Just use a servo extension cord and plug it in to the balance plug on. The battery and connect the other end to the balance port on the charger. It is only a two cell battery so the servo extension works fine since it has three wires. Of course you still have to connect the main charge cord to the battery.

telejojo 12-14-2012 04:10 PM

RE: LIFE battery charging in the plane question
 
Charge mine in the plane I can't think of any reason to take them out just to charge.

Truckracer 12-14-2012 04:32 PM

RE: LIFE battery charging in the plane question
 
Quote:

ORIGINAL: WRM

RCU is acting up . I fly with 8711s and have since they came out and not had a problem . You are probably right ,the hobby shops will make us change so we have to buy all new batteries and chargers . It's all about money.
Actually most hobby shops were slow to adopt the LiFe or A123 technology. Modelers started using them obtaining cells from drill packs, etc. then a few vendors started selling them to the hobby market. Others were marketed to the RC car guys but they were never especially popular there because LiPos took over that market. This all happened quite awhile before most hobby shops started selling these batteries on a regular basis.

If a Nixx battery is the same weight and capacity compared to most any LiFe or A123 battery, I guarantee the Nixx battery will have a far higher impedance. It will simply not be able to supply the same amount of current while maintaining a usable voltage than the LiFe battery will. The Nixx battery will be rated to deliver its capacity at a lower current over a longer time than the LiFe battery.

There are many quality Nixx batteries out there but at similar C ratings, the Nixx will be much larger and heavier than similarly rated LiFe batteries.

Similarly, given similar ratings, genuine A123 batteries far outperform any of the soft pack LiFe batteries and I use both.


kwblake 12-14-2012 04:35 PM

RE: LIFE battery charging in the plane question
 
WRM, the hobby shops cannot force you to do anything you don't want to do. Ni-hm will be around for a long time yet. I think what most people here are getting at, is, that sometimes new, is better. I also use Life batteries, and really like them. You should stick to what you are comfortable with. There is a cost to getting into Life, or A123, because of the charger, and, they do not give the batteries away, but they are awful good. If you are interested, check out http://www.hangtimes.com/ Lots of really good info there.
Quote:

ORIGINAL: WRM

RCU is acting up . I fly with 8711s and have since they came out and not had a problem . You are probably right ,the hobby shops will make us change so we have to buy all new batteries and chargers . It's all about money.

wesaysoracing 12-14-2012 05:51 PM

RE: LIFE battery charging in the plane question
 
i just put a balance extension on my LiFepo4 batteries and charge them in the plane

bbagle1 12-14-2012 10:48 PM

RE: LIFE battery charging in the plane question
 
I bought my balance extender from wrong way rc. The extender connects to the battery on one end and the other end is a balance jack that mounts on the fuse just like a charge jack on a switch. So you can just connect the chargers balance board to this jack via a cable they sell to charge or connect to the balance jack and the usual charge jack to fast charge. Still able to do both from outside the plane. I believe the balance extension with fuse mount was $9 and the adapter that runs from the balance board to the fuse mount was $9. At $18 not the cheapest alternative but definitely seems like a good solution and couldn't be any simpler.

4*60 12-15-2012 12:57 AM

RE: LIFE battery charging in the plane question
 
Add balance connectors. That's great, but I will say that using LIFE(both A123 and plain LIFE) packs for receiver packs I do not balance them. As I understand if you are drawing small current and charging a reasonable level(under 1C), no balancing should be required. 2 seasons and counting...and I'm not the only one at our location.

LIFE are not LSD they are NSD (low self discharge, no self discharge) effectively. Forget to charge the pack flown 6 months ago, which was drawn down 20%, you'll still have most of the 80% left and are safe. NIMH, even Eneloop are LSD. Low internal resistance so they perform well when a higher draw is required.

Oh, did I mention price. I sell LIFE 1100 mah packs here LPU for $10 or 2 for $15, sometimes.


PHall 12-15-2012 05:29 AM

RE: LIFE battery charging in the plane question
 

Quote:

ORIGINAL: WRM

Why would I go to LIFE and stop using ni-mh? The LIFE is heavier and has to be balance. What is the advantage?
Long story made short....you get more usuable energy from a Life.

rc74 12-15-2012 05:57 AM

RE: LIFE battery charging in the plane question
 
A lot of time and enengery went into keeping up with my nimh, big pain in the ass. Using nothing but A123 now. 12 plus planes love it. Example: 12 flights on my 1/3 scale Stearman before needing a charge . Great for info ( Electro Dynamisc and Radical RC)

HoundDog 12-15-2012 06:49 AM

RE: LIFE battery charging in the plane question
 
<h3><font size="4">Personally I fly Sanyo Eneloop NMHI batteries in my smaller planes ( 60 to 125) size Nitro and some Electrics with out BEC's  Great Battery <font size="4">2000 MAH and <font size="4">holds</font> a charge for ever.  But for my big Gasse<font size="4">rs I've gone to 2500 M<font size="4">ah LIFE 2 cell packs fro<font size="4">m Hobby King. About $9 shipped<font size="4">. I <font size="4">use two in each plane with 2 heavy duty switches<font size="4">, some through a<font size="4"> Batt Share some <font size="4">plugged</font> directly into my<font size="4"><font size="4"> <font size="4">Aurora</font> 9 <font size="4">rx's. the reason is that the Sanyo <font size="4">Eneloop's don't have the out put for the larger loads of the Bigger servos.</font></font></font></font></font></font></font></font></font></font></font></font></font> Just my 2 cents worth. I also have the luxury of being able to remove and reinstall  the LIFE batteries in my big planes quickly.<br type="_moz"/></h3>

airraptor 12-15-2012 08:22 AM

RE: LIFE battery charging in the plane question
 
So much misinformation in this thread.

1. Charge batteries with the correct charger
2. Monitor batteries when charging
3. Cycle your battieres when you first get them to see if they are at the rated capacity and discharge them at the rate used in the plane at max working load IE say 750-1,000 MAH per servo. Once cycled a couple of times write down the dishcharge time and capacity save it for later use. Cycle your batteries once a month out of the plane (balance them if LiFe or LiPo)
4. Know the discharge curve of your batteries
5. Only Fly to the 50% of capacity or while talking at the club top off at the field
6. Read the directions that come with the battery and know how to use your batteries

Most problems with equipment in our planes, cars, boats, helis and so on are user error not equipment error!

Four Stroker 12-15-2012 09:04 AM

RE: LIFE battery charging in the plane question
 
You can't really compare a high internal resistance cell like a AA Eneloop with an A123 M1 cell for weight. If you use digital servos of anything past 50 in-oz, you should not use AA cells. The 2700 A NiMH cells aren't much better. You should compare a Sanyo CP 2400 5 cell pack to a 2S A123 pack which have about the same specs for BOTH current and capacity. The A123 wins big time. Also note that NiMH cells dump in cold weather. I originally went with Sanyo 4/5 FAUP 1950 cells. They were fine until it got cold - 50F. I was completely happy with Sanyo RC 2400 packs when they were available some 10~15 years ago. I went to A123 because I kept buying "new" NiCD packs that had set around a warehouse for years. As Red said, NiCD cells are dead after 7 years (shelf life) if you have used them or not.

I have a concern about cell redundancy. If one cell fails in a 2S pack, you are probably coming down. A 4 or 5 cell pack can tolerate a dead cell and keep right on going. I used to put diodes across the cells (ancient idea) in case one of the cells "opens". But 1 A123 cell plus a diode is 3.6 - 0.7 = 2.9 volts optimistically and at least Futaba digital servos die at 3.2 volts. I have a VoltMagic thing set up to go yellow at about 50% capacity remaining at which time I BALANCE charge the pack at 2.3A - about 30 min.

1) you should loosely mount your batteries in foam or several layers of foam tape
2) you should not over charge or discharge

rexbirk 12-15-2012 09:39 AM

RE: LIFE battery charging in the plane question
 

Quote:

ORIGINAL: allelectric

After two battery fires in different club members planes. (Who are 20yr + AMA members) No thanks! I will charge my batteries OUT of my planes. They say ''its NOT safe'' for a reason;)
Not sure what type of batteries caught fire but I understand the A123 technology does not have that issue. I have been using them for several years and they seem bulletproof. The A123 cells have a metal jacket around each cell like a nimh cell. I have never seen any of mine even get warm during a charge. I suppose anything is possible if misused though. Mine stay in the plane to charge. They charge so fast though that staying with them during the charge is not an issue.




drac1 12-15-2012 12:14 PM

RE: LIFE battery charging in the plane question
 
I have not used A123's/LiFe batteries. I use Li Ion batteries in all my planes and charge them in the model with no problems. They don't have the same issues that LiPo's have.
Li Ions don't lose charge when not being used and they do not require balancing. If you want redundancy the 4 cell pack has this. It is basically 2 x 2 cell packs, if one cell fails it will not affect the other 2 cells. The 4 cell pack is charged through one charge lead.
I would not use anything else.


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