Duralites for your Turbine!
03-25-2003 | 05:49 PM
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From: Deland,
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look at cost
Using Tom's numbers, lets look at cost vs energy capacity;
The old standby: Nicad 2400 MaH, 6V, $45
Energy per dollar -> ( Mah * V)/ $ = (2400 * 6)/ $45 = 320MahV/$
The challenger: -> Li-ion 3600 Mah, 7.4V, $90
(3600*7.4)/ $90 = 296 MahV/$
So, the difference in direct cost vs the total energy capacity is about 8%. Pretty good cost for leading edge technology.
Of course if you need a new charger, etc that's a consideration. Not a cost that will likely go away if you wait a year though.
The old standby: Nicad 2400 MaH, 6V, $45
Energy per dollar -> ( Mah * V)/ $ = (2400 * 6)/ $45 = 320MahV/$
The challenger: -> Li-ion 3600 Mah, 7.4V, $90
(3600*7.4)/ $90 = 296 MahV/$
So, the difference in direct cost vs the total energy capacity is about 8%. Pretty good cost for leading edge technology.
Of course if you need a new charger, etc that's a consideration. Not a cost that will likely go away if you wait a year though.
03-25-2003 | 06:19 PM
#27
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Duralites for your Turbine!
Crap......I had already decided to use nicad's in the BC. I would like to take advantage of new technology (all jet guys do by the nature of the powerplant) but since this is my first turbine, I really don't want to be on the cutting edge. Not charging every flight and built in redundancy sounds really good though.....
BOB
BOB
03-25-2003 | 06:54 PM
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From: Daytona Beach
Re: look at cost
Originally posted by Johng
Using Tom's numbers, lets look at cost vs energy capacity;
The old standby: Nicad 2400 MaH, 6V, $45
Energy per dollar -> ( Mah * V)/ $ = (2400 * 6)/ $45 = 320MahV/$
The challenger: -> Li-ion 3600 Mah, 7.4V, $90
(3600*7.4)/ $90 = 296 MahV/$
So, the difference in direct cost vs the total energy capacity is about 8%. Pretty good cost for leading edge technology.
Of course if you need a new charger, etc that's a consideration. Not a cost that will likely go away if you wait a year though.
Using Tom's numbers, lets look at cost vs energy capacity;
The old standby: Nicad 2400 MaH, 6V, $45
Energy per dollar -> ( Mah * V)/ $ = (2400 * 6)/ $45 = 320MahV/$
The challenger: -> Li-ion 3600 Mah, 7.4V, $90
(3600*7.4)/ $90 = 296 MahV/$
So, the difference in direct cost vs the total energy capacity is about 8%. Pretty good cost for leading edge technology.
Of course if you need a new charger, etc that's a consideration. Not a cost that will likely go away if you wait a year though.
Good points john! BTW....Emory and I had the same discussion about Gary and the lithiums. The cells I am using are li-ion not the poly's (yet). There ARE cells coming that will give nicads a run for the money. There is one fault in your #'s above. The cells I am currently using are 4.2 volts, giving me a pack voltage of 8.4 so...
(3600*8.4)/$90 = 336 MahV/$
Plans are for Ocala this weekend, you coming? Call me
Todd
03-25-2003 | 06:57 PM
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Li are O.K., really.....
Hey, don't get me wrong, Patrick. Long before most of the R/C world knew that Lithium could run ECU's in addition to treating manic-depressive illness, I was into them. Had one in my full scale plane(not re-chargeable) powering my Emergency Locator, until the FAA banned them due to fires and explosions, over-reaction on their part, of course. Now back to Alkalines with a 2 year shelf life, rather than 10 year of the lithiums----talk about progress. Leave it to the feds.
I actually have tried one of the original Tadiran Duralites from Canada in one of my light weight prop planes 2 yrs ago. Li-Ion is actually old technology, dating to the early 90's. Actually modified a Radio Shack power supply into a CVCC charger. That has been replaced by my new UltraDuo 30 which does a great job on Li charging. Worked fine, but that 600 mah pack lasted about 1 month until I forgot to turn off the rx(no low voltage cutoff on it). Shortly after that, that original run of Israeli Tadiran Duralites disappeared as you probably know, and I kinda lost interest, although for a while, Rich Fong, myself, and a few others experimented with tearing apart camera and computer batteries in search of substitutes. I tried to find those old thread, but they seem to be lost. So been there.............
Johnny Hernandez has been using them successfully for a long time.
I also have used nothing but Li in my laptops and cameras for years. Li techno invaded ham radio stuff at least 5 years ago.
All of those packs have the protective over and discharge protection which has worked flawlessly for me, but as you probably remember, there have been major recalls on laptop lithiums due to fire and explosion with some of the earlier models.
Additionally, NiMh techno is advancing fast. The new low internal resistance packs are just about to hit the market, providing power density even closer to Li than NiCads. The EF guys are drooling.
If for no other reason than environmental concerns, Nickel Cadmium batteries are going to become history. Wisconsin DNR is getting nasty if they catch you throwing these into the general garbage heap.
I am actually quite elated that Todd "made the switch #2", cuz now he will have more time to help me make FT's trailer I just bought look like his own, which is kick-butt, while he is waiting for his Li's to charge. :>)
Most CVCC chargers are set to 4.2/8.4v for Li-ion cell(s). The cells come off the charger at 8.4v, but are rated at 3.7v/7.4/cell(s). I have never seen a 4.2v Li-Ion, but depending on chemistry, I have seen 3.0, 3.6, 3.7, and 3.8v cells.. As opposed to nicads and NiMh which lose that surface charge rapidly, Li's hold onto it for days, even weeks in my experience. The photo is of one of my 7.4/1550 packs that is fully charged and floating at 8.4v.
Tom
I actually have tried one of the original Tadiran Duralites from Canada in one of my light weight prop planes 2 yrs ago. Li-Ion is actually old technology, dating to the early 90's. Actually modified a Radio Shack power supply into a CVCC charger. That has been replaced by my new UltraDuo 30 which does a great job on Li charging. Worked fine, but that 600 mah pack lasted about 1 month until I forgot to turn off the rx(no low voltage cutoff on it). Shortly after that, that original run of Israeli Tadiran Duralites disappeared as you probably know, and I kinda lost interest, although for a while, Rich Fong, myself, and a few others experimented with tearing apart camera and computer batteries in search of substitutes. I tried to find those old thread, but they seem to be lost. So been there.............
Johnny Hernandez has been using them successfully for a long time.
I also have used nothing but Li in my laptops and cameras for years. Li techno invaded ham radio stuff at least 5 years ago.
All of those packs have the protective over and discharge protection which has worked flawlessly for me, but as you probably remember, there have been major recalls on laptop lithiums due to fire and explosion with some of the earlier models.
Additionally, NiMh techno is advancing fast. The new low internal resistance packs are just about to hit the market, providing power density even closer to Li than NiCads. The EF guys are drooling.
If for no other reason than environmental concerns, Nickel Cadmium batteries are going to become history. Wisconsin DNR is getting nasty if they catch you throwing these into the general garbage heap.
I am actually quite elated that Todd "made the switch #2", cuz now he will have more time to help me make FT's trailer I just bought look like his own, which is kick-butt, while he is waiting for his Li's to charge. :>)
Most CVCC chargers are set to 4.2/8.4v for Li-ion cell(s). The cells come off the charger at 8.4v, but are rated at 3.7v/7.4/cell(s). I have never seen a 4.2v Li-Ion, but depending on chemistry, I have seen 3.0, 3.6, 3.7, and 3.8v cells.. As opposed to nicads and NiMh which lose that surface charge rapidly, Li's hold onto it for days, even weeks in my experience. The photo is of one of my 7.4/1550 packs that is fully charged and floating at 8.4v.
Tom
03-25-2003 | 11:46 PM
#30
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Duralites for your Turbine!
I've spoken to Bob Wilcox and he says not to use Lithium batteries with the JetCat ECU. Bob explained that these batteries do not have the amperage capacity to adequately start the turbine and run the ECU. This was especially troublesome with an older starter motor that was a little "draggy". Bob still recomends NiCads for the ECU/starter use and going with the 3000 mAh pack if you want extra flight time before charging. Thought you guys would want to know....
Kevin
Kevin
03-26-2003 | 12:17 AM
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From: Daytona Beach
Duralites for your Turbine!
Kevin,
When was the last time you spoke to Bob about the Li-ion batteries?? I think you will find if you call Bob that his tune will have changed a bit (since we have talked numerous times about my tests). Jetcat Germany has been experimenting with Li-ion for a bit now and the new P-70 may even come supplied with a li-ion pack.
I have successfully flown a Jetcat P-120 for five flights without a charge on a Li-ion pack, Obviously they do have the amperage capacity to start the Jetcats....Not once but multiple times....They work!
Todd
When was the last time you spoke to Bob about the Li-ion batteries?? I think you will find if you call Bob that his tune will have changed a bit (since we have talked numerous times about my tests). Jetcat Germany has been experimenting with Li-ion for a bit now and the new P-70 may even come supplied with a li-ion pack.
I have successfully flown a Jetcat P-120 for five flights without a charge on a Li-ion pack, Obviously they do have the amperage capacity to start the Jetcats....Not once but multiple times....They work!
Todd
03-26-2003 | 12:29 AM
#32
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Hi guys,
I am all for experimentation, but I got to clarify.
The experiments in Germany are with Lithium POLYMERS, not Lithium Ion. Does not mean Lithium Ions will not work, but I doubt JetCAT will be offering them anytime soon, whereas there is a good chance that the P-70 will offer Lithium Polys as at least an option.
IMHO if you can get enough current to get through start up, then your battery will work. The highest current loads are during start up, and as some have noted the peaks for a JetCAT are quite a bit lower than at least one competing turbine manufacturer, I don't know about any others
Please I hope this does not get emotional or personal, I know many of the guys on this thread (Tom, Todd, Tony, etc) and these guys are DO-ERS....I like do-ers! Keep experimenting and exchanging ideas guys!
As for me (personally) I kind of look at batteries like I do fuel tanks or air cylinders, they have to be filled every flight. I like to have a smaller battery and charge every flight.
I use 2 RX packs and use maybe 300 mah (total) per flight, so with a Sirius Pro pumping in about 4 amps total, I am ready in just a few minutes. I usually run 2 amps on the Orbit as well for the ECU pack. This is just a personal preference, I do not like the idea of needing to remember how many times I have flown. And for me I do not like not being able to effective field charge the lithiums.
But I definitely like reading about the experimenters and compare notes, so keep it coming.
The experiments in Germany are with Lithium POLYMERS, not Lithium Ion. Does not mean Lithium Ions will not work, but I doubt JetCAT will be offering them anytime soon, whereas there is a good chance that the P-70 will offer Lithium Polys as at least an option.
IMHO if you can get enough current to get through start up, then your battery will work. The highest current loads are during start up, and as some have noted the peaks for a JetCAT are quite a bit lower than at least one competing turbine manufacturer, I don't know about any others
Please I hope this does not get emotional or personal, I know many of the guys on this thread (Tom, Todd, Tony, etc) and these guys are DO-ERS....I like do-ers! Keep experimenting and exchanging ideas guys!
As for me (personally) I kind of look at batteries like I do fuel tanks or air cylinders, they have to be filled every flight. I like to have a smaller battery and charge every flight.
I use 2 RX packs and use maybe 300 mah (total) per flight, so with a Sirius Pro pumping in about 4 amps total, I am ready in just a few minutes. I usually run 2 amps on the Orbit as well for the ECU pack. This is just a personal preference, I do not like the idea of needing to remember how many times I have flown. And for me I do not like not being able to effective field charge the lithiums.
But I definitely like reading about the experimenters and compare notes, so keep it coming.
03-26-2003 | 12:38 AM
#33
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Duralites for your Turbine!
Todd,
It's been a few months since I've spoken to Bob...He was definately against it then. Maybe he was referring to the older Lithium Metal packs instead of the newer Lithium Ion. I'm glad you are researching this for us! Your tests are very promising. My charger is Lithium Ion capable as it is the same one (Schulze) that Nico described and Bob Wilcox sells. I guess all I need to do is to buy the batteries. Really, for me, charging isn't that much of an issue. I'll charge while my buddy flies his jet and vice/versa. For me, the benefit would be reduced weight for better grass field performance. Again, good job with your tests.
Kevin
It's been a few months since I've spoken to Bob...He was definately against it then. Maybe he was referring to the older Lithium Metal packs instead of the newer Lithium Ion. I'm glad you are researching this for us! Your tests are very promising. My charger is Lithium Ion capable as it is the same one (Schulze) that Nico described and Bob Wilcox sells. I guess all I need to do is to buy the batteries. Really, for me, charging isn't that much of an issue. I'll charge while my buddy flies his jet and vice/versa. For me, the benefit would be reduced weight for better grass field performance. Again, good job with your tests.
Kevin
03-26-2003 | 02:39 AM
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From: Fond du Lac,
WI
Li again...
Hi Matt:
The lithium-ion refers the anode construction. In rechargeable Li's, it is ionic Li dissolved into a carbon electrode, whereas in non-rechargeable, it is non-ionic metallic lithium in various forms.
The Cathode is usually an oxide of Cobalt, Manganese, or the newer Phosphate. Environmentalist are liking the Phosphate, since the Cobalt and Manganese are not as friendly to the environment.
The polymer refers to the electrolyte, something like LiCl(original Tadirans had a proprietary thionyl chloride), which is a gel in most of the Li's that have been mentioned in this thread, and can leak, so it has to be contained in a metal container. It also has an organic component(usually some form of tetrachloride) that can burn and explode.
In the Li-ion polymers, the free electrolyte is immobilized(hardened) so there is no need for a metal case to prevent leakage. They are getting 3.8v at high energy densities out of this stuff, and already are sticking it into cell phones and computer packs. You can mold it into the smallest, weirdest shapes if you want. The guys at Sandia and at Oak Ridge have taken this even further with their super thin wafer cells. The military and the auto manufacturers are chomping at the bit.
That was the point I was making initially. It won't be long before those packs will be readily available on the R/C market---the old, heavy, tin can Li packs will become obsolete. Begs the question "Why buy old techno, when new stuff is right around the corner"...wait a few months, put up with those old NiCd or NiMh, and then drop a load of money on the newest stuff..........
You still have to face the problem of limited high current flows in the Li chemistry(impedance), but with this new technology, you can stuff a bunch more capacity into a small foil wrapped package to make up for this deficiency. That's why JetCat is probably interested in the Li-Ion Polymers.
Ain't no engineer! Just passing along info I gleen from my Ham Radio Mags, Scientific American, and other nerdy rags. Photo is just a sample of some of the stuff coming down the line. Actually, don't have to wait too long. I see where Skyborn, FMA and CheapBatteries, and others are already advertising the polymers.
And if all this doesn't put you to sleep, drop over to the batteries section of RCU, or the battery discussion section of E-Zone. Most everything you ever wanted to know about Liths, both batts and chargers has been covered in detail, many times over.
Tom
The lithium-ion refers the anode construction. In rechargeable Li's, it is ionic Li dissolved into a carbon electrode, whereas in non-rechargeable, it is non-ionic metallic lithium in various forms.
The Cathode is usually an oxide of Cobalt, Manganese, or the newer Phosphate. Environmentalist are liking the Phosphate, since the Cobalt and Manganese are not as friendly to the environment.
The polymer refers to the electrolyte, something like LiCl(original Tadirans had a proprietary thionyl chloride), which is a gel in most of the Li's that have been mentioned in this thread, and can leak, so it has to be contained in a metal container. It also has an organic component(usually some form of tetrachloride) that can burn and explode.
In the Li-ion polymers, the free electrolyte is immobilized(hardened) so there is no need for a metal case to prevent leakage. They are getting 3.8v at high energy densities out of this stuff, and already are sticking it into cell phones and computer packs. You can mold it into the smallest, weirdest shapes if you want. The guys at Sandia and at Oak Ridge have taken this even further with their super thin wafer cells. The military and the auto manufacturers are chomping at the bit.
That was the point I was making initially. It won't be long before those packs will be readily available on the R/C market---the old, heavy, tin can Li packs will become obsolete. Begs the question "Why buy old techno, when new stuff is right around the corner"...wait a few months, put up with those old NiCd or NiMh, and then drop a load of money on the newest stuff..........
You still have to face the problem of limited high current flows in the Li chemistry(impedance), but with this new technology, you can stuff a bunch more capacity into a small foil wrapped package to make up for this deficiency. That's why JetCat is probably interested in the Li-Ion Polymers.
Ain't no engineer! Just passing along info I gleen from my Ham Radio Mags, Scientific American, and other nerdy rags. Photo is just a sample of some of the stuff coming down the line. Actually, don't have to wait too long. I see where Skyborn, FMA and CheapBatteries, and others are already advertising the polymers.
And if all this doesn't put you to sleep, drop over to the batteries section of RCU, or the battery discussion section of E-Zone. Most everything you ever wanted to know about Liths, both batts and chargers has been covered in detail, many times over.
Tom
03-26-2003 | 05:34 AM
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From: Seoul, KOREA, REPUBLIC OF (KOR)
Lithum Polimer Batteries.
Dear Friends,
First I am not good at batteries but I know recent lithum Polimer batteries are not yet sufficiently stable for power source. First mr friends say that it can draw around 4C maximum, whilst one of Korean Manufacturer is almost succeeding to improve it upto 10C and going to release in the market soon.
We had tested it in our turbine engine ECU and Starter. In case of J600 when starter revoles, the currency draw upto nearly 9-10 ampheres momentarily. But in a seconds, it goes down to 3-4 only when turbine running smoothly.
This means that when we use new battery technologe with Li-Pol is rather O.K. and quite reliable. I am going to use over 4,000ma Li-pol for my twin turbines.
However, if you are going to use it for RX with number of digital servos, I would strongly recommend to refrain. We tested high torque digital servos with checker and found tremendous draw of currency momentarily. For example, if you have tester, please try it. One servo used draw more 4-5,000ma if it is forced stopped by hands. If you imapgine with 6-7 digital servos and try high G-turn or quite sharp manuver, your battery volts will suddenly dropped below rx managable. and plane will be dead stick.
Mostly we here use still heavy Ni-cd with 12-13C capability of draw currency. It is sleep easy equipment still.
Meantime, I changed switch with toggle type (strong springs) instead of sliding one. We also make two leads from battery pack and two leads to rx, one for battery slot, the other for empty slot. We found sometimes, switch capacity is not enough to pass the battery capacity to RX and servo.
We have Kokam Brand which is really revolutionary technology for electric motor and planes. But due to reason above we refrain to use it for RX yet. But if it is not digital servo and not heavy plane I would think it is o.k.
Jai Young Shim
First I am not good at batteries but I know recent lithum Polimer batteries are not yet sufficiently stable for power source. First mr friends say that it can draw around 4C maximum, whilst one of Korean Manufacturer is almost succeeding to improve it upto 10C and going to release in the market soon.
We had tested it in our turbine engine ECU and Starter. In case of J600 when starter revoles, the currency draw upto nearly 9-10 ampheres momentarily. But in a seconds, it goes down to 3-4 only when turbine running smoothly.
This means that when we use new battery technologe with Li-Pol is rather O.K. and quite reliable. I am going to use over 4,000ma Li-pol for my twin turbines.
However, if you are going to use it for RX with number of digital servos, I would strongly recommend to refrain. We tested high torque digital servos with checker and found tremendous draw of currency momentarily. For example, if you have tester, please try it. One servo used draw more 4-5,000ma if it is forced stopped by hands. If you imapgine with 6-7 digital servos and try high G-turn or quite sharp manuver, your battery volts will suddenly dropped below rx managable. and plane will be dead stick.
Mostly we here use still heavy Ni-cd with 12-13C capability of draw currency. It is sleep easy equipment still.
Meantime, I changed switch with toggle type (strong springs) instead of sliding one. We also make two leads from battery pack and two leads to rx, one for battery slot, the other for empty slot. We found sometimes, switch capacity is not enough to pass the battery capacity to RX and servo.
We have Kokam Brand which is really revolutionary technology for electric motor and planes. But due to reason above we refrain to use it for RX yet. But if it is not digital servo and not heavy plane I would think it is o.k.
Jai Young Shim
03-26-2003 | 07:18 AM
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From: Fond du Lac,
WI
Li-ion vs Li-ion polymer (LiPo)
Matt:
#1 url-This guy clears up the Li-ion vs Li-ion Polymer terminology that is so often mistated, even by some battery retailers.
#2 url-Red S. and the rest of the gang on RCU batts has had many posts on the Kokam LiPo.
Like you said, it will be interesting to see Todd's long-term results. Also, wonder what the longevity of the packs is going to be at those high discharge rates(anything above 2C) on the ECU packs during startup? Allot of this has been done with electrics and written up, but I have not seen a post specific to the JetCat.
http://www.powerpulse.net/powerpulse...a_080601a1.stm
www.fmadirect.com/support_docs/item_1080.pdf
Tom
#1 url-This guy clears up the Li-ion vs Li-ion Polymer terminology that is so often mistated, even by some battery retailers.
#2 url-Red S. and the rest of the gang on RCU batts has had many posts on the Kokam LiPo.
Like you said, it will be interesting to see Todd's long-term results. Also, wonder what the longevity of the packs is going to be at those high discharge rates(anything above 2C) on the ECU packs during startup? Allot of this has been done with electrics and written up, but I have not seen a post specific to the JetCat.
http://www.powerpulse.net/powerpulse...a_080601a1.stm
www.fmadirect.com/support_docs/item_1080.pdf
Tom
04-09-2003 | 11:24 PM
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From: Lafayette,
LA
duralites
Did you run the pack without the regulator?
did you beef up the leads from the battery to the connector.
did you splice a deans or other connector onto the duralite lead or did you put a futaba or jr connector on the lead coming from the ECU?
any help would be appreciated
did you beef up the leads from the battery to the connector.
did you splice a deans or other connector onto the duralite lead or did you put a futaba or jr connector on the lead coming from the ECU?
any help would be appreciated
04-10-2003 | 01:35 AM
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From: Daytona Beach
Duralites for your Turbine!
Hey Rick,
The Duralite (turbine pack) came with 16ga leads. You have the option of 16 or 18ga. It has a seperate charge jack that passes through a special charging circuit to avoid overcharging. This lead is a typical JR/Hitec plug. I did splice the main lead and add a deans plug to disconnect the pack during charging since Jetcat recommends this practice (I also already had a deans plug on the ECU side from the nicad pack that was orig. installed). Certain types of chargers can damage the ECU during the charge phase, since I was not sure if the lithium type charger is a type that can damage the ECU I decided it would be best to unplug during charge. I have manged to get 8 starts/flights on this 3600 mah pack, more may be possible but have yet to fly the plane more than this in a single flying session (I have three planes flying). After 8 runs the pack was still showing 7.4 volts and my typical flight time on the EF is 9 min and 12-14 min run time! No regulator is needed with the Jetcats but one may be necessary with other brands of turbines depending on ECU input voltage.
Feel free to contact me if you have any further questions...
Regards,
Todd
The Duralite (turbine pack) came with 16ga leads. You have the option of 16 or 18ga. It has a seperate charge jack that passes through a special charging circuit to avoid overcharging. This lead is a typical JR/Hitec plug. I did splice the main lead and add a deans plug to disconnect the pack during charging since Jetcat recommends this practice (I also already had a deans plug on the ECU side from the nicad pack that was orig. installed). Certain types of chargers can damage the ECU during the charge phase, since I was not sure if the lithium type charger is a type that can damage the ECU I decided it would be best to unplug during charge. I have manged to get 8 starts/flights on this 3600 mah pack, more may be possible but have yet to fly the plane more than this in a single flying session (I have three planes flying). After 8 runs the pack was still showing 7.4 volts and my typical flight time on the EF is 9 min and 12-14 min run time! No regulator is needed with the Jetcats but one may be necessary with other brands of turbines depending on ECU input voltage.
Feel free to contact me if you have any further questions...
Regards,
Todd
