Arrow IV

I'll be the first to admit that Corky from Life Goes On would hand me my ***** in a spelling B, but what is the deal with Lithium Batteries? Regulators, Smart Fly Systems, Deans Plugs, Chargers, Balancers, Testers, this gauge wire, that gauge wire, don't over charge them, don't run them out of juice, they are only good for 2 years, not too hot, not too cold, disconnect your batts when you get done flying due to discharge, and my favorite "...NEVER charge a pack in a model...", are you flippin kidding me???... Dude I'm about ready to strap five 6V nimh 4500 mah to my Extra and call it a day.... As if you couldn't tell, I'm a pilot first and everything else a distant second... Can someone please tell me if this apparent "Ivy League Lithium Battery" education is worth the price of admission??? For example, (please correct my rookie mistakes if need be) Battery to the switch, switch to the regulator, regulator to the receiver AND ALL THE DAMN PLUGS ARE DIFFERENT! What's with that?... Anyone got a little light to shine on this for me?

jetmech05

It's because lipos can be dangerous....I have seen a lipo get punctured and the fire that results....
Ok now that that is out of the way.....a battery is a battery as far as what to do with the electricity that is produced....so battery to switch to regulator to reciever is correct.
Now you've gotten some stories mixed up.
1 some switches don't completely disconnect a battery, they have something in their internal circuits that drain something like 10ma a week....so you hear disconnect a battery. I have LiFe and LI-Ion batteries and I don't disconnect them....nor do I use those switches. Plus it's battery to switch then regulator not batt to regulator to switch...that keeps the regulator drainning the battery
2 don't charge a lipo in an airplane...If I was using a straight lipo I wouldn't....as they can swell from over charging...then you can't remove them or you damage your airplane..or if they catch on fire you don't have a plane...Yes I've seen that too, almost cost my club a covered pit area.
3 I don't use deans plugs
4 smart flys...I don't use a smart fly...I would I just haven't yet....a smart fly can do many things for you...a voltage regulator and a kill switch plus a way to power your receiver at 6V and allow 7.4 V to high voltage servos
Hope this helps ya

vasek

My Feedback: (4)

I have to agree A, some people go overboard with batteries. It's like servos, some will only fly a plane with $100 servos in the plane [X(]

But there is the 2.4 brown out issue now. I don't know why, but instead of making the new equipment better (in all respects) it seems to have gone the wrong way as far as volt sensitivity is conserned[&o]

There has been so much a LiFe & LiPo trend that some people argue an RC plane will crash if using Nimh for Rx power. But a broad recall of the most popular line of regulators doesn't worry them too much. Go figure[X(]

Well that's LiFe (pun intended)

Steve Percifield

My Feedback: (14)

Arrow,

Very well put.

I like the dudes who tell me "I can fly all summer on 1 charge",, They must generate electricity??? I'm with you. I'm sorry, they are a pain.... I just ordered 2, 2700 mah, 5 cell Nicd packs, I still run them in all my stuff, old fashioned but bullet proof. I guess I'll have to charge them every time i fly...

jester_s1

Using lipo's ain't all that complicated. Even the stuff the OP mentioned isn't much to know. Yes, you have to have the right charger. Then same is true for NiCd's, except for the fact that a NiCd charger has become standard for the hobby so it doesn't seem like it's specialized. Yes, if you fully discharge them it can ruin them. The same is true for the lead battery in your car, but nobody complains about that, do they? (unless you've done it!) If you are drawing a lot of amps, you need heavy gauge wire. That's not an issue specific to Lipos but to electricity in general. If your wire becomes a choke point the whole system suffers. If your receiver and servos are designed to run at 6 volts and you want to use a lipo that puts out 8 volts fully charged, you'll need a regulator. That's because you are adapting a newer battery technology to use with equipment designed for the older NiCd/Nimh batteries. The one really fussy part about using lipos is charging safety, which is simply a quirk of the design. The stuff inside is flammable and if you have a pack rupture from overheating or damage it goes up pretty spectacularly. Ignore that little detail at your own risk, but please do so far away from me and my models.

Villa

I have seen a model helicopter in the air on fire. It used Lipos. A few days ago a foam model plane caught on fire after landing and was a total loss. Lipos. I screwed up and connected two Banana Plug batteries together when I meant to connect one to my Lipo charger. Destroyed both batteries. Another member did the same thing about one month later. Both of us will be changing the connections to the Dean Plug connectors. These plugs prevent that type of screw up. If you are going to use battery power for propulsion it is best to give it the attention it needs. I have one electric plane, a flying wing, with landing gear. I am very happy with it. Been flying RC since 1972. I know that my flying wing is possible only because of the use of Lipo batteries. The other batteries are just too heavy. Like any new development, the electrics are in a transition period and a lot of care and attention is needed.

Arrow IV

Excellent info gents, much appreciated! Might be about time to pack my Steve Austin lunch box and catch the short bus to Lithium School... I know one of these days I'm going to have to make the jump, cause them 35% airplanes with 8 monster servos working thier backsides off eat batteries like Rosie Odonell at an $8 buffet!!!....

Sir Percy, about 94% of me is with you, if the damn thing ain't broke don't go grabbin wrenches. You're spot on, the 6V nimh's are bullet proof (and idiot proof, thank god...), you can beat the crap out of those things, abuse the snot out of them and they just keep coming back for more! NEVER had an issue with them. It's that last flippin 6% that's got me going, fly once or twice and re-charge... Some days I feel like I head to the field just to run my mouth and charge batteries, somptins godda give...

Maybe a little pre-education if y'all don't mind (sorry, I'm in the south, if you don't say "y'all" at least 4 times a week they kick you out of the state...) Anyone got a grocery list of items required to get this pig to fly? Here's what I think I know: I'll need 1 or 2 batteries, 1 or 2 regulators (right? 1 per battery?), 1 or 2 switches, a charger, a balancer and a voltage read out (whatever you call the thing to check the batts before and after flights). Am I missing anything? I'm kind of eyeballing the Fromeco gear, any opinions? They say they're the best so it MUST be true......... LOL!!!....

Bozarth

My Feedback: (15)

A very level headed post.
Kurt

Edwin

My Feedback: (2)

Hmmm, does a house burning down sound like hysteria? A club member almost had that happen. A lipo spontaineously burst into flame in his garage. He just happened to be in there when it happened. Yesterday at our big bird a lipo battery was ejected from its plane, and puffed and started to burn, we were fortunate to get it onto the runway. Two weeks ago, a crash caused a fire that was put out with a fire extinguisher before it got too big. This was in a large cedar break. Cedars burn like roman candles. A month ago about a 50yd sq fire burned and had to be put out by the fire dept. I personally watched a pattern plane blowing flames out the bottom cowl as it was landing. Lipo education is first on the list for my electric students. Like was said, its mostly common sense, but these fires this year were all experienced electric pilots.
Edwin

Bozarth

My Feedback: (15)

Sounds like your field is either built on an old Indian burial ground or on an island in the Bermuda Triangle. Tell us where you fly and we will all try to fly somewhere else - I don't want any of my airplanes spontaneously combusting! Didn't I see an episode on your field on Spike TV?

Edwin

My Feedback: (2)

Spike TV? Dont know what you're refering to. The big fire wasnt at our field, someone was flying outlaw. When you have a lot of electric flyers, you're bound to see more of the bad. Most of them are 3D pilots. And the field is Austin RC.
Edwin

After rereading my first post, it DID sound like a pretty bad year.

jetmech05

There are advantages and disavantages to flying Lipo's......Like I said I fly Li-ion and Li-Fe batteries.....the charge lasts a long time even after using them...I have a 50CC pitts python using 7 digital and 2 standard servos....I fly 4 to 7 flights a weekend...and only charge about every 6 weeks or so.....I charge my Li-Ions when the voltage on the packs gets to 7V under a 1/2 amp load.....they are 2600 mAh batteries.....I use a Turnigy charger set up for the proper pack as the voltage is different for li-ion vs life batts with a max charge on a lipo at 1 amp....It takes a bout 2 1/2 hours to charge.....
I maybe wrong but Li-Ions and Li-Fe batts don't seem to as critical as the lithium polymer batts...but I keep my eye on them any way while charging......
My new airplane is a Pilot RC 50CC Yak 54 I'll be running the Li-Fe batteries in them...2 for system using 2 seperate switches, and seperate voltage regulator going to a batt share.
I didn't hesitate to run LI-XX in this airplane.
You can destroy a Ni-cad or a nickle metal battery as well from over charging...as a matter of fact some Ni-cads can get thermal runaway and burn...but I have never heard of this happening in RC.....
Don't be afraid of using Li-XX batteries I sure like mine

vasek

My Feedback: (4)

2 funny

syamaner

In our local forum we always have a similar discussion. Some friends say "LiPo + UBEC is the best" and others say "the only battery for RC is NiCd".
I am using all kinds of power sources in my RC aircraft. NiCd, NiMh, LiPo, LiIon and LiFePo. Usually I use NiCd and NiMh in 4 AA packs, LiPo and LiIon with UBEC and LiFePo in form of 2S package without a regulator.
For me the most funny statement is: "A LiPo flies much longer than a NiMh with the same capacity"!!!
The most funny moment was when I discovered that one of my frieands had joined the LiPo, UBEC and the receiver to a packet using tie wraps. He was complaining of temporary control loss during flight!!! The UBEC and the receiver MUST be positioned so that they are furthest possible from each other.

I never recommend complex setups like lipo + UBEC to beginners. I don't think there is a reason to use a LiPo on a trainer with four standart servos. But if someone is familiar with RC aircraft, batteries, electronics and soldering he/she can decide which is the best. Of course, to be able to do this one should know the advantages and disadvantages of every setup.

NiCd:
(+) Simple setup. Can handle relatively high currents. Relatively flat discharge curve.
(-) Memory effect. Enviromental issues. Charge loss during waiting. Low recharge current. Long recharge time.

NiMh:
(+) Simple setup. Relatively flat discharge curve.
(-) Memory effect??? Some voltage drop with high current draw. Charge loss during waiting. Low recharge current. Long recharge time.

NiMh (New Generation)
(+) Simple setup. Relatively flat discharge curve. Practically no charge loss during waiting. Relatively high recharge current. Relatively short recharge time.
(-) Some voltage drop with high current draw.

LiPo + Linear BEC
(+) High current available. High recharge current. Short recharge time. No charge loss during waiting.
(-) Relatively complex setup. More risk points in the wiring. Danger when recharging. Steep discharge curve near the end of the capacity. Low efficiency and heat production (due to linear BEC)

LiPo + Switchmode BEC
(+) High current available. High recharge current. Short recharge time. No charge loss during waiting.
(-) Relatively complex setup. More risk points in the wiring. Danger when recharging. Steep discharge curve near the end of the capacity. Risk of electromagnetic interference (due to Switchmode BEC)

LiFePo
(+) High current available. Very high recharge current. Very short recharge time. No charge loss during waiting. No need for a regulator (may e a risk for older equipment). Can be charged on the aircraft.
(-) Weight?

My two personal favorites are in bold...

acdii

I use LiPo in my 4 planes, and only the tiny one has had an incident. It hit nose first and ejected the battery, which broke the end off of it. It shorted and ballooned, but didnt catch fire. This was an Ultra Micro plane with the 150mah 1s pack. My big birds, the T-34 and Apprentice use 3300MAH 3S Lipos. I use extreme care with them, replaced the dinky banana plugs and EC3 connectors with Deans, I use care when connecting them to my charger, one short can spell the end of the pack, and could cause it to go POOF in flames. The cable I use to charge it has banana plugs to connect to the charger and they were loose, so I expanded them to be tight. I always put the pack in a LiPo bag when charging and make sure the charger is correctly configured so it doesn't charge too fast. The charger also has a thermistor that I put on top of the pack while charging which will shut the charger down if it reaches a certain temp.

Never overcharge a Lipo, don't let the voltage drop below I think its 3.4V per cell, and the pack will last a long time. If the pack is warm, let it cool before charging. If the pack is cold, warm it up before using it. That's like if its in the fall or spring when it is 40* outside.

Most important of all, Do not use too small a pack for a heavy amp draw motor! If you do your plane will burst into flames at some point! Lipo's will not start on fire on their own, something needs to happen to the pack to cause it to flame. If you draw current out of these too fast they may puff up, and if they do, toss them as they are no longer any good. Too fast a draw can heat them up very quickly and if it is a hot day out, say in the 90's, they could exceed their heat limit and spontaneously combust. They may not like vibrations either since they are mainly used for EP planes and cars.

Their internal connections may come loose from the vibrations and short it out, which will cause it to burn. Most of the packs I have seen are individual cells wired in series. NiCd and NiMH battery packs are individual metal can cells spot welded to each other so you never see this happen with them.

One thing about Lipo's I found, they will maintain their charge for a very long time. A friend of mine bought some batteries, an ESC, motor and plane a few years ago, and never touched any of it. He didnt get a charger with them either, so I hooked one up to my charger to check if the pack was still good, and the voltage was dead on at storage of 3.8 per cell. The receipt was dated 2008.

So take care of the packs and they will last you. Just use common sense with them and they wont harm you. As with anything, if it crashes, just inspect closely, and if you see any damage to the case, your best bet is to toss it.

vasek

My Feedback: (4)

acdii, so you don't charge the lipo in the plane, right?

If you had to leave the battery in the plane when charging, would you still use a lipo?

Edwin

My Feedback: (2)

Maybe we need to get the field blessed or something. A rain dance wouldnt hurt either. I stick to lipo 3s sizes up to 2600ma for my electrics. All my wet power and transmitters are nimh.
Edwin

syamaner

I always balance charge my LiPo's without removing them from the plane.

I have a question to those who use a LiPo and a regulator as a receiver battery on a glow or gas powered aircraft: Do you use a 2S or 3S LiPo?

acdii

No on both counts. For one thing the planes I have use the battery for the motor and the radio, and are designed for quick swap out. The other is you always want to examine the flight battery after every flight to make sure it isnt over heated, or if a wire got damaged.

Fo those using them as radio batteries in a glow or gas plane, charge at your own risk if you leave them in the plane. For one thing I really dont see a need to use the more expensive Lipo batteries to run the radio unless you are only doing it to save on wieght. Lion batteries though Idont see any risk charging in the plane, they arent made the same as Lipo.

As far as 2s or 3 s that all depends on how many volts you need. If you have no need to go beyond 7.4 volts, and are just looking for capacity, use a higher C rated battery and higher MAH 2S. You arent gaining anything by using a 3S. Only time you need to consider more cells is if you want more volts, and that is only for EP planes. The higher the volts the more RPM you can get from your motor, and longer flight times if you can gang your packs together. All of that of course has to be taken in consideration with the higher weight of the packs, the larger ESC and motor to run higher volts.

vasek

My Feedback: (4)

May I seek your advice on how optimize this setup for a quick swap out? thanks!

2walla

My Feedback: (10)

I have seen a LiPo fire burn a plane down, had a LiIon fire do to a charger malfunction AND a Ni-Mh fire due to a short.. All of the newer high capacity/discharge batteries can cause some serious damage. You need to have a healthy respect for all batteries.. I pretty much run all A123's in my planes now as they are a bit safer.. My LiPos all live in a bunker outside the house and are transported in steel ammo cans.. No way would I take a lipo inside the house or charge it inside..

Valve floater

Are deans the best connectors? That`s all i use and never had a problem.

Bozarth

My Feedback: (15)

There are thousands of us out here who charge lipos correctly and without fires! Just like a lot of us gun owners - we have experienced years of success without accidentally shooting someone or having our ammo blow up in the car. Take proper precautions and enjoy the technology.

The sky is not falling, nor is it catching on fire.

Kurt

Rcforme...

A lot of people think NIMH is safer, but this is the thing. LiPo's do tend to explode more than NIMH's, but when they explode, it's a safer situation than when a NIMH explodes. LiPo's are flamethrowers and NIMH's go off like a grenade. LiPo's burn things down and NIMH's blow apart whatever they are in or near.

DanMN

There is no hysteria in my eyes. I have over 30 lipos of various sizes and some are over 3 years old and have been cycled countless times. Some are a little puffy, but still charge fine and fly fine. I am careful when I charge them with means that I set the charger correctly..... I charge them in my garage on a concrete floor. I haven't had any fires, etc. The only fires I have seen happened after a crash which the battery was mostly destroyed and punctured. No hysteria please. Come to think of it, I almost burned my house down recharging a 12V starter battery (gel) when I put the leads on backwards. Thank God I smelt the plastic burning. Lipos are good. Just do some reading on them. Preferably not from a post with the word hysteria in it. You don't have to charge them in a bomb shelter.........