One of my biggest complaints is I spend more time charging than flying. I am extremely "Battery Stupid", I try to keep things as simple as possible to avoid any losses due to battery failure. Since Emory Donaldson from Duralite is right here in Daytona Beach, we met for lunch to discuss using a Duralite pack to run my turbines (don't trust anything but nicads for the receiver packs yet! ) with the possibility of getting multiple flights without charging. We discussed my concerns and Emory assured me he had the solution. After getting a brief lesson on Lithium batteries and how to care for them I was presented with a Duralite 8.4 3600 Mah pack, field/home charger and load tester. The Duralite weighs less than half of my current 1200mah nicad pack. According to Emory, I should be able to get 10 flights before needing a recharge! Plenty for a days worth of flying.....

Well....I put 5 flights on my P-120/Eurofighter combo with the Duralite installed without a hitch. Engine fired every time (being able to supply start-up amperage was a concern) and average flight time was 13 min from start-up to shut-down. At the end of flight 5 my voltage under load was 7.50V, I was warned not to discharge the pack lower than 6.9V or I could damage the pack. According to my calculations, I can probably fly 8 flights safely with my 13 min average before needing to recharge. Works for me :bananahea
Now I just have to learn to trust them on my receiver and I wont have to charge at all at the field.....

Duralites are the solution to your charging blues.... I would imagine they will become the norm for all turbine packs in the near future.

Just thought I would share,
Todd

Todd,
I was also testing using a duralite for my turbines (RAM 500 and RAM 1000). At a full charge I could not get the battery to spin my 500 starter motor at all and it would spin the 1000's motor ok. Was going to give up on it and start testing the pack with my receiver and see how it would perform in that environment. Now with your success I might have to rethink this. Just a couple of quick questions for you.

1. Was it a 7.2 v 3600 Mah pack or did he add in a couple extra cells and make it a 8.4 v pack? (is it 4 cells or 6)

2. What gauge wire were you using going from the battery to the ECU?

3. If it was a true 8.4v pack did you have to use a voltage regulator to avoid frying your ECU.

Thanks any information would be very useful.

Patrick.

Todd,

You might want to PM or email TonyF before you get all excited about Li-Ions. Ask him about how he lost his Bandit.

David

Todd

Are you operating with multiple batteries, RX, ECU and servos? Any type of power distribution isolators?

Not sure what type of 1200mAh NiCad you were using but a 5-cell JR Extra 1400mAh weighs 6ozs. The Duralite Plus 3600mAh battery pack weighs in at 6.6ozs. plus the regulator. You have a considerable capacity gain, but a weight savings is unlikely unless you were using sub-c cells.

All Duralite Plus batteries are comprised of at least two individual cells rated at 3.7V. 2)3.7=7.4V. Hot off charge they may exhibit 8.4 I suppose.

The 3600's are two pair of two 1800mAh cells wired in series-parallel. This can be construed as a redundant power supply as you basically have two 7.4 battery packs wired together with either one or two pigtails to supply power to the switch/voltage regulators. The primary reason these battery packs are wired in series-parallel is to provide a power source that can handle the high current demands of multiple digital servos. Li-Ion cells provide nearly twice their rated capacity in amperage. Which simply means an 1800mAh cell can deliver 1.8Ah x 2 = 3.6 amps. 3.6Ah x 2 = 7.2A. Note on a comparative basis this is much, much, much less than a NiCd/NiMH is capable of delivering. This is the achilles heel of this technology. While high in energy density Li-Ion's operate with very high internal resistance.

For the high current demands of the ECU, fuel pump and on board starting equipment it would be a pre-requisite to use the series-parallel battery packs. Attempting to use an 1800mAh battery would provide less than stellar performance, if that.

Todd:

Mike's comments are well taken.

I use nothing but matched Sanyo CP-2400SCR nicads, preferably from SR or Andy Low with the husky leads and the best connectors.

You can do 5 JetCat 10 min start-to-stop runs with this pack, and a similar # of flights on the RX pack.

These cells can be re-charged at 5 amps safely. I re-charge between flights in about 4 minutes/pack at the 5 amp rate.

Get one of those nice UltraDuo 30 that Camillo sells, and one of John Burdin's 12volt batts, and you won't have time for a smoke between flights....... :>)

Tom

Comments well taken guys....Let me explain things further.

I believe these are new cells compared to what you are used too... These cells are 4.2 volts each and 1800 mah, each pack consists of four cells which as Mike said, gives you basically two 1800mah packs in one battery. The pack came pre wired with 14 guage leads and handles the startup current just fine. I checked with Bob Wilcox about the higher voltage (8.4 vs 7.2 ) and he said it was not a problem for the ECU, I do suggest you check with your engine manufacturer to make sure the voltage is not a problem. Currently I am only using the Lithium pack on my ECU, I have not switched my receiver packs out yet but I am open to testing some in the future.

Tom,
Now remember....I am battery stupid here .... If you charge a pack at 5A doesn't it discharge at a much faster rate as well? I just dont trust slammin that kind of juice into my packs. I prefer to slow charge and monitor exactly what went back in. I dont mind waiting 20 - 30 min between flights (I just fly another plane) but dont want to wait an hour for both packs to be done. The Duralites seem to resolve that problem quite nicely without the added weight penalty of the larger nicads.
BTW....Quique Somenzini (SP?) has been using the Duralites for years on his TOC planes without a hitch, he is driving many more servos than I ever will in one plane....If he can draw this kind of current why would we have any problems in our jets???

Flanker,
Please explain further....PM me if you would prefer. I heard tony lost his bandit but thought that was the frequency control issue??

Regards,
Todd

The factory is experimenting with Lithium Polymers (not sure what duralites are, used to be lithium ion).

Anyway, initial impressions are good, but we will publish the final specs after complete testing.

There is a reason a RAM might not work with these types of batteries and JetCAT will, so as Todd said I would check with your turbine manufacturer and not just depend on the JetCAT data.

Todd:

I believe with these high mAh Nicad packs you need to "push / charge" them once in a while at much higher than "c rate" to ensure they will stay at rated capacity. I'm sure Red Scholefield in the Battery and Charger forum could verify this.

Thanks

Originally posted by lov2flyrc

I heard tony lost his bandit but thought that was the frequency control issue??

That was the F86, not the bandit.

Gordon

I do monitor, or should I say, the Graupner UltraDuo 30 does monitor how much goes in. If I do a discharge cycle after a high current charge, I actually get more mah out at the higher charge rate than a lower rate.

Lithiums are coming along though. Jim Oddino's first review in RCM a couple of years ago was unfavorable for some of the reasons Mike mentioned above, but now with the newer lithium ions, and larger capacity packs, he gave a more favorable review in his latest RCM article.

You still have to be much more careful with these packs or you will end up with an explosion or junk, depending on whether you overcharge or overdischarge them.

Tom

Interesting that you got 8.4 v pack. I thought Duralites(lithium-ions) were all 3.7 v/cell and came in 7.4 v packs

I've been running the Duralite Plus for some time now in my giant scale aerobatic aircraft with no problems whatsoever.. Doesn't mean there aren't failures as ANY piece of our hobby can suffer from periodic failure. It's just a part of the hobby and nothing will ever be 100% reliable.

A friend of mine is running them on his new BVM Bobcat w/P-80 without issue as well but I don't think he's using them to power his ECU. I think those are still NiCD's.

I have complete confidence with Duralite Plus batteries and Emory in his support of his products.

Doug Cronkhite
Team JR

Actually.. the original Duralites were Lithium Metal. The new Duralite Plus and Powerflite systems are Lithium Ion. Powerflite also has the Lithium Polymer batteries as well, but I haven't used them.

-Doug

Honestly, I don't know how this sort of misinformation gets out there. I really don't know why the Bandit crashed. I lost control of it on the downwind to landing, right after I put the flaps down. I seriously doubt it had anything to do with the RX batteries. I had two packs installed, so both would have had to fail. And it was just the second flight of the day.

I have a very high level of confidence in the DuraLite Plus batteries. My BobCat had flown about 100 flights with them, and before I installed them I was using the original DuraLites. The Sabre also had them installed before it got shot down at Sepulveda. None of my turbine jets have flown with anything but DuraLites in them.

I do know that when Bob Wilcox looked at the ECU after the Bandit crash, the only data he could get out of it was a data bit that is the JetCat "Power Fail" info. If this bit toggles it means either the ECU pack went below a certain value or the R/C pack went low. Bob had assumed I had shut off the engine before the crash and thought the R/C packs had gone low. However, I had not shut off the engine, so I feel the engine was running when the model crashed and the ECU pack got ripped out. This toggled the "Power Fail" data. My personal opinion is that the crash was either interference, or something failed on one elevator and the other elevator did not have enough control power to get the nose up. But I will probably never know for sure.

I was going to start experimenting with the DuraLites on the turbine right after AZ Jets, but unfortunately I don't have anything left to test with, so I have never tested the packs on my P-120. I had earlier used the packs in my RAM 500 powered Sabre, but I had mixed results. Frankly, the RAM autostart system is pretty crude, and requires much higher current during the start then a JetCat.

As far as charging safety, DuraLites are now ahead of the game on that one. All DuraLite packs have a protective circuit installed in the pack to prevent any charging accidents.

If and when I ever get around to building any more jets, they will have DuraLites installed. They have proven to me to be the best battery system available.

I use nothing but matched Sanyo CP-2400SCR nicads, preferably from SR or Andy Low with the husky leads and the best connectors

These cells are designed for fast high current charge (up to 5A)and high current draw, typically you can dump these in excess of 20 amps. Matched cells or packs are even better, as the entire pack is only as good as the weakest individual cell. Very good choice for the ECU system, possibly overkill but why not.

I don't recall any data supporting the concept that fast charging cells cause's them to discharge faster, this is function of current demand.

Typical RX packs should not be charged at more than 2A and a quality peak detection charger should be used. I field charge mine when required with a Sirrius Limited Edition dual RX charger, 2700mAh NiMH 5-cell packs peak in less than 20 minutes typically.

With today's NiCD and NiMH type cells I believe fast charging the cells with hi-tech chargers does not present any problems, that said on occasion I'd recommend balancing the cells with a slow charge for an extended period of time. Cycling your batteries on occasion to verify their capacity is valuable, this exercise provides actual data for determining if capacity degradation is or has occurred.

Theres two schools of thought on the charge protection circuit concept utilized exclusively on the Duralite Plus cells. Severely over charging Lithium-Ion cells can produce disastrous result's (small explosion's and or fire are not uncommon).

1] Charge protection circuits electronically limit the peak voltage to prevent over charging and subsequent damage to the cells. The draw back is they can provide an additional on-board failure mode IF wired through the power pigtail. These protection circuits have been known to fail and they fail open circuit, meaning no voltage passes to your toy airplane if wired as such.

Duralite Plus uses a second or independent pigtail to curtail the possibility of an open circuit failure.

2] Other companies that offer Lithium-Ion technology such as Power Flite and Super Battery Packs offer smart chargers, similar to peak chargers. These chargers have the protection circuits built into them. No possibility of on-board failure modes! I have yet to hear of problems or failures with this approach.

Lithiun-Ion battery packs require the use of a specially designed charger. You cannot use any other charging equipment.

Hi guys,

As with Todd/Tony, I've got a set of the Duralite Plus packs for testing on PST's ECU. I'll post some performance data when the weather's good enough to get out again. My only real concern is the current draw during E-start application with glow on, but after speaking with Jack and knowing the basics of the startup algorithm, I don't expect it to have any trouble.

My first impression was that it looks like a quality product and Jack Price is pretty knowledgeable about the technology, (read: useful product support...). I also like the stand-alone charging port on the battery pack. The plug is yellow to keep users from mistaking it with the Rx charge port, pretty much fool proof. I agree it's unfortunate that the pack needs a unique charger, but if the capacity is there and reliability follows suit, the extra charger seems pretty insignificant in my opinion. As you can see, the gear won't need much space in the field box. (hmmm... RCU won't let me post a picture, I know its within posting specs...?)

I've got 20 L of fresh fuel ready for the test bench and feeling quite optimistic after reading Todd's and Tony's posts. The charger I'm using is the single output type, not the 4-port unit that available as an option. The single port charger can be used at home with the 12V wall adaptor or at the field with the supplied cables. I suspect the 4-port version is the same.

Overall, nice stuff! we'll see how it works out.
Later,
Kelly

Ive been following the battery forum on Ezonemag, and what is being discussed there is pretty awesome. Li-Poly battery's with 10C and even 20C discharge rates are just around the corner. Looks like edf is going to get a BIG kick in the fan this year, should be very interesting.

Todd:

Are Duralites Li-Ion or Li-poly? I got the short course on Li-poly ,which are just maturing, at Giants this year. There was also an article in MAN about them recently. From what I saw, the article in MAN was quite a bit behind the state of the art on these things.

A fellow named Gary Wright was at Giants flying one of those "Team Hacker" e-powered Funtanas. He also had a 40 size 3-D plane. He had a Li-poly pack in the 40-size that he used for deep 3-d including hover for more than 25 minutes on one flight. That is, he had hover power thru the 25th minute. He had a pack that would allow similar performance for the Funtana - a 120 size airplane. Based on what I saw, Li-Poly is the future. My take on them is that they are at least on the performance level of the Li-ion and more user friendly. Gary seems to be using the best stuff, stuff not quite released for sale even.

He posts around here as gwright and seems to know a hell of alot about Li-poly. Plus, he's right here in Melbourne. Seems like you are very happy with the Duralites. However, seems to me that those have been marketed to and used in low-current situations. Gary has a handle on using Li batts for power. Might be an alternative.

I feel very strongly about a Charge Safe Circuit being installed in Lithium-ion and Lithium Polymer battery packs. It monitors each cell’s voltage and the total pack voltage during the charging cycle. Battery pack suppliers supporting other industries are installing this type of circuitry. Why would the major suppliers of Lithium-ion and Lithium Polymer batteries Sanyo, Panasonic, Ultralife and Saft refuse to sell a pack without this protection.

As you can image there is a substantial cost for the circuitry, extra pigtail, and other required parts to make a safe pack.

DURALITE PLUS Battery packs are supplied with TWO leads.

The BLACK POWER LEAD is connected directly to the battery pack cells allowing for uninterrupted power to the receiver and servos; it does not pass through the charge circuitry. This is the same power connection to the cells/pack utilized by all Nicad and NiMH pack builders. This black connector plugs into the switch harness as usual.

The second lead is a YELLOW connector and is only used during charging, it has no effect on the power being supplied to the receiver and servos.

When connected to the charger the current passes through the YELLOW connector and the Charge Safe Circuitry allowing for a fast and safe charging process. The charging process is the most critical in regards to safety. The Charge Safe Circuitry is installed in the pack to monitor each cell’s voltage and the total pack voltage during the charging cycle. This allows each pack to be charged to the proper voltage providing safe charging, maximum pack performance, and long life.

We prefer not to rely on a charger to safely control the maximum shut off voltage of a Lithium-Ion or Lithium Polymer battery. There is always the potential that an inappropriate charger, malfunctioning charger, or an incorrectly programmed charger being connected to a Lithium-ion or Lithium Polymer pack.

Have a great week!

Emory

"Duralite" batteries are also known as Tadiran cells, or Lithium Mangan-Oxide Batteries.

"Duralite Plus" batteries are probably Li-Ion cells.

This is the information found in my manual of the superb isl-6-330d chamäleon charger of Schulze. (This charger is a further developement of the sophisticated and well known Ultra Duo Plus charger that Schulze is producing for Graupner.) This charger can handle most types of batteries, including Li-MnO and Li-Ion.


Li-MnO : (=Duralite or Tadiran)
-----------
3.0 V / cell
Charging : with max 0.35 C
Discharge (long periods) : with preference max 1.5 C
Storage : cells must be stored FULLY charged.


Li-Ion
-------
3.7 V / cell
Charge : with max 1 C
Discharge (long periods) : with preference max 4 C
Storage : Li-Ion cells must be stored DISCHARGED (with the auto-discharge program)


Best regards,
Nicolas.

Unfortunately I do not succeed to post a jpeg photo of this charger on this thread, but all information can be found on :

http://www.schulze-elektronik.com

[email protected]



Best regards,
Nicolas.

Li technology is moving ahead. Lotsa info appearing in the camera mags. I love them in my cell phones and digi cams, but the practicality of using them in all my planes is doubtful at this time. By the time you get 2-3600 packs and all the accessories from scratch, you have over 400 bucks in the first 2-3600 packs and then about 180 bucks for every 2 packs you get from that point on. I plan to fly 4 different planes this summer.

To re-pack all my planes and get the necessary accessories would cost just under $1000.00.

The Sanyo CP-2400SCR go for about 4.95 a cell or $45.00 for a wired up 5-cell pack. You can charge these with any peak charge you have laying around, never have to worry, unless you really abuse them about explosion or fire, never have to poop-can a pack if you let the voltage drop just a little too low, and get 5 flights out of them before a recharge, using JetCat ECU. I still recharge after every flight just to remind myself to do it, and to get max spin on the starter motor to keep temps as low as possible.

Sanyo 5-cell packs come in a couple of configurations, and weigh 10.6oz, a mere 4 oz more than a 7.4/3600 Li.

Plus, if I want to fly 10 flights on one plane on that perfect Saturday when I am at the field from sunrise to sunset, how do I do that with the lithiums, which according to Todd's experience are maybe O.K for 8 flights, but probably only 5 to be safe. That means having a backup packs available, and having it stuck in the plane where I can easily get at it to swap it---and another $180.00.

It sounds like we are probably a year away from the really great new Li stuff hitting the market, not only for R/C but for cameras, phone, computers, etc.

At this time, I think they are probably a safe alternative, not a true replacement for nicads, but an expensive one at that.

Tom

C'mon Tony - drop the "if" and concentrate on the "when" - we can't have one of our best turbine guys gravitating back towards the dark side and going back to 'pattern' or sumfink like that

Have you had any luck yet in recovering the funds awarded to you in the Sepulveda court case ? Hope so !

Later,
Gordon

I hate to hear statements like that because those kind of statements are what cause new innovations to take forever to get better. I have been in the computer field for sometime now and have seen the development of Li-Ion batteries develop well pass nicads. Yes, I would have agreed with tom about 3-5 yrs ago, but now Li-Ion batteries are the main stay in almost all your electronics today. Digital cameras, Camcorders, cell and home phones, and computers. I own a laptop that originally came with a Nicad pack and when unplugged just sitting idle I could get only about 30 minutes runtime out of it. Now the manufacturer has supplied me with a Li-Ion retrofit and now I can go almost 3.5 hrs before having to recharge.

Now we as modelers are always testing out new designs of airplanes and making changes, modifications, and suggestions on how to make the aircraft better and I think that is what todd has in mind. Don't just dismiss the technology as being a year away from innovations because if we don't give emory feedback on what we want then how can he make a better product for us. Stop discouraging Todd from doing his tests and getting some very good data for future development of these batteries.

Patrick.

Just my .0000025 worth

Thanks Patrick! That was a breath of fresh air.....

It's amazing, you mention you are having good performance from an newer product on the market and immediatly all the "Nay-Sayers" line up to throw stones. I constantly hear people trying to knock down the lithium technology but they never have any valid data or proof to back it up. Yes, lithiums cost more than your generic nicads but...have you priced a nicad pack that will give me the same performance I am getting from this lithium pack? A typical 3300mah Nicad pack average price is 70.00, the 3600 mah Duralite I am using is 89.00 (I believe). Special charger? Yes, you need a charger designed for Li-ion, my camaleon from Graupner would do just fine. Let me also add that after further discussions with Emory about my battery consumption, I am convinced I can get 10 flights from the 3600 Lithium pack before needing a charge. BTW, as mentioned earlier the Duralite pack use a second connector that is only used during charging/load testing, it has no effect on the power being supplied to the turbine/receiver and servos. Yes, you can field charge you Li-ion pack! The Duralite charger is capable of field charging as well as my camaleon which I already had.
A year away from great Li-ion stuff hitting the market?? It's here now! That is the point of this thread . I am getting consistent starts, long flights without having to charge....Seems to me I have found exactly what I was looking for. Sure, there will always be progress in the battery field but the technology is here now!
Will I try them on my receiver, Sure....Why not. I am drawing more amperage on turbine startup than my receiver will ever see. The batteries have higher capacity, lighter in weight and are very simple to charge and maintain. Sure, they cost a little more but to fly all day without having to charge is well worth the extra expense to me.
I will keep this forum updated with my progress if there is interest.
Todd

TonyF & Company,

Didn't mean to start something, I just had some apparently bad information about the loss of your Bandit. That's why I didn't push the issue and suggested that Todd contact you directly.

David