Its only true, if u dont need some amps. Im flying a 4m electro powerd sailplane. i need endurance and long fly times - but at the start, i need at least 90 amps. so its not useable. thats what u have to be different. depends on the real plane - not only if using a copter or a plane - or using racing or long range. u have to know your max possible amps drawing - no matter of what u flying
Great video as always. I would just add that the surge in battery wholesalers in the past 2 years has really changed the economics. For example, you can get LG MH-1 or 18650BD cells with 3.2Ah and 10A continuous for about 1.50 USD each. Lately "salvage" means never used because companies go bankrupt before even selling one scooter or bike. So, a 4s2p is maybe 13 USD with wires and heat shrink and is good for maybe 4 times the charge cycles of LiPo. Another advantage of LiIo is configuration. You can pretty much make the pack any shape you want. Center of gravity off? Form a 4s tube that runs the length of the craft. Only have an "L" shaped space left in your bay? No problem. Lastly, with balance equalizer boards, you can say goodbye to balance chargers and hello to 24/7 cell balancing, including during flight, at any discharge level. In other words, LiIo looking better every day.
Been flying 18650 VTC5D as my preferred cell and VTC6A for almost a year now. Primary pack is 6s2p configuration for 7in on 2806.5 1300kv Avengers or 10inch on 3115 640kv motors. Can very nearly rip quite nicely on 3s VTC5D packs with 3600kv 1406-1506 sized motors and 3.5in triblades. Best to have an amp meter so you can use Betaflight to run up your motors tab and see at what throttle you hit 15 amps and 25 amps. Then make sure you have throttle % active in your OSD because many of the small budget 4:1 escs do not have a current sensor so go by throttle % instead. Have also run two packs for 6s4p on 13inch Xclass cruising for 18 minutes at a constant 50mph. Soon will have 4 sets of 4s2p built for 6in drones but used for paralleling and series for 8s4p on the Xclass becase it really wants 32v instead of 24.
You ever should keep in mind when using liion. Due to the voltage drop you should always add 1cell. So if you're using 4s, with liion you take 5s and you're fine. For high current use vtc6 with 3000mah, for lower current use GA series with 3500mah.
@@Migueldeservantes better to think of it as driving down current draw as you increase voltage. Consider 800 watts needed to fly. At 2s and 8 volts you are doing 100 amps. Versus 4s and 16v you are doing 50 amps. Are those the actual values? No. But it shows how a build in 4s could sag your batteries more than the same build on 6s, voltage drives down amps. Then if you need more amps build in parallel. I figure my 6s2p packs are good for a solid 30 amp continuous discharge with a 60amp burst. VTC5D and VTC6A cells should be considered 15 amp continuous at best and 30 amp burst for short duration.
Dude I really really like your videos. I started a Inav adventure with a 7” build about a month ago and watched many of your videos to build it . Maiden on Sunday went perfect . 9 minute flight time on 4s 1500 lipo 3.8 per cell after rest . 20 satellites. I was too paranoid to try RTH or position hold but everything else worked . Very stable and easier to fly acro then stable mode . Now of course it’s time to build some 18650 packs.
These cells are great for many applications. The current limitation does make it tricky for hobby use though. Since the only real way to lower current for a given vehicle is to add cells either increasing voltage or running them in parrallel, either way you need more cells. For a flying machine that means more weight and space needed as well as cost. This quickly takes us past the point of diminishing returns. However, if you do run parrallel packs you really up your capacity. So a carefully planned craft could yield great results in terms of flight time. I just purchased some sony 30a rated cells to mess around with but they are NOT cheap for the real ones. It's going to be hard to beat lipo for the time being. Cheers
I'm using 4S3P battery (Molicel M50A cells) on my 2m Opterra. Gives me over an hour of cruise time with a comfortable reserve. BTW thanks for the tip on the soldering acid!
Good video, Paweł! Thanks! From experience using a 4S1P Sanyo GA (alternatively LG MJ1) on the Z84 during takeoff it does take more than the max 10A (as per spec). This, however lasts only for about 5-7 seconds because the moment the plane starts moving the strain on the propeller decreases rapidly as soon as the air starts moving through it. Using autolaunch is even better because the moment the prop starts the plane already is moving forward and thus the time the battery experiences high drain is even shorter. I also use a 3Ah HG2s (20A) on my 250mm miniquad and I get around 15-18 minutes of cruising (no aerobatics!). The pack really weights a lot less than the 3Ah 2S lipo that would make the quad unflyable.
No one talks about the charge times for these things though... You need to set them round 1.5a charge rade doubling your typical charge times frequently timing out the charger lol. Not that it's a huge deal breaker. But it's often neglected to mention that while you can discharge them lower you don't really get a load of useful power as it doesn't have punch to keep you flying normally..it's safe in that you can fly longer but once you start to feel the sag you'd best start heading home to land.. you can cruise back home and not have to worry about destroying the pack though that's great.
@S Grim they are good packs you just have to know what you're getting with them and how to fly these packs the higher discharge versions are more expensive and some reviewers actually use the low discharge ( c rating ) when discussing them this gimping the review. They can be good just have to pick the right one for your exact application. I'd only wanna use them for cruise or long range and again you have to know exactly when to turn back
Tesla's new cylindrical cells are pretty impressive, they modified the construction of the cell to avoid all the current going through small tabs, allowing the cell to dissipate heat more efficiently and reduce ESR. I expect these cells, with the right chemestry, to perform on-par with pouch cells (what everyone in this hobby calls "LiPo" (for the record, they both have polymer separators, but there are many dozens of lithium chemistries out there that are subsets of lithium ion. the high performance 18650's use INR.)
@@avsaase I do hope someone takes the idea and applies it to 18650's. I doubt it will happen because Tesla patented the idea and probably have the patent for this process applied to 18650's as well, even though they will not benefit from this (unless they begin manufacturing 18650s to sell to an open market) I doubt they would sell 4680's either, they would need to be salvaged. I think 4 to 12 of them would be excellent for a 7" to 10" build!
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We need affordable and compact high voltage escs handling 8s or 10s and combine with low kv motors, so we can keep current low, and use thinner wires etc. The Molicell 21700 are very good also
I'm testing the Samsung 21700 40t. In the Fms cessna the average consumption is 15A and peaks of 20, with very little power drop compared to lipo. I have tested a 40 A discharge bench and they can withstand them but with more pronounced power drops and high temperatures. I think it is a good alternative in motorsailers.
Combination of the regular Lithium batteries with supercapacitors may be the best of both worlds. Weight and storage may have some challenges but the good news is that the supercaps are very light Weight and carry a good punch like for take off like a chock absorber for the batteries so that the up front current is provided without over straining the batteries. I used this method on solar backups to help with things like air-conditioner compressor kicking in and it seems to work great. Just an idea I am sharing. It may make a nice experiment using drones.
Well stated Pawel, for wing cruiser LiIon 18650 are cool. I can fly 45 minutes plus with the mini AR Wing cruising 60+kmh on 3s Sony VTC6. Launch no issue using iNav autolaunch,
The miniwing's motor takes only 10A at full throttle so it should be easy. I bought a 3S liion from ZOHD but it is too tall! :/ So I've just purchased a ZOHD Dart 250g which should have more room. I'm a bit worried about the launch tho. It has a smaller motor than our AR miniwing... Gotta throw hard!
I think it would really interesting to see li-ion cell with tesla tabless design. It should be much capable to dump large current, without being constrainted by the narrow tab in cell battery. But we probably won't see it in years because of tesla holding the patent.
I like the idea because there are INR Type of cells they are allow 30A Constant current. So a 4S2P Pack would deliver 60A Current wich should be good for easy flying. And we are Talking about 7Ah 4S and 580G weight. Li-fe is also interesting because of the long Cycle life wich is 5-10 Times more than Li-Po
Li-FePO4 is much lower energy density in size and weight they're good for replacement with standard lead-acid ones. But not for drones even Electric vehicles.
I fly bigger EDF jets and I power them with Molicel P42A cells. Their specs state 45A max discharge, so I always use 2 in parallel and add more cells then a LiPo setup would have. My Freewing Avanti can go 220kmh+ and still have a 5min+ flight time. There are some tradeoffs - one needs to drill holes for cooling and wire multiple packs properly (I use 10S2P with 6S and 4s packs) When Molicel releases the the P45B cell then it will be a total no-brainer to use these over Lipos ;)
Hi Adam, I noted your reply regarding bigger EDF jets. I am currently (no pun) using 6S 4000 75C lipos to power a 90mm EDF, which draws 110A full throttle. I read "I always use 2 in parallel and add more cells than a lipo setup". Do you mean add series cells? Change 6S to 7S ?? Are there any other brands, with equivalent performance? Happy flying 👍
@@davidwatkin1484 At the moment Molicel P45B is the best li-ion cell, I am not using P42A anymore even ;) Just google the topic of "connecting cells in series and in parallel"
The one big issue I have with 18650 cells...is that they only come in one physical size/ capacity....18650. This is why the 4 inch LR quad is designed around 4 X 18650 cells.... Very limiting.
My experience: 5" slim frame, full Gopro8, 2550KV 5S motors, 5.1x3.1 props, LiIon 6S pack 3150mAh: hovering/slow cruise (first test) flight time 25minutes. end voltage 2,5V (sum 15V at the end)
Some good information. And some useful tips . BUT VERY LONG DRAWN OUT TO THE POINT. AS A EXPERIENCED HOBBYIST. TO BEGINNERS IT COULD CAUSE THEM A LOT OF CONFUSION. BUT APPRECIATE YOUR INFORMATION.
Now I understand why Zipline Drones use a catapult for takeoff Will there be a followup ? Tips for building Liion? Yes, the soldering video is out there but soldering isn't the whole build Btw.: Good overview
I use 21700 cells more than 18650. One thing I wish iNav had was a preset for liion for battery profiles. I run both lipo and liion in my planes and have profile. Would be nice if in the configurator you could choose battery type along with the battery profile.
It looks like the 7" GEPRC Crocodile I'm building will get 8 cell Li-Ion packs in series/parallel 4S configuration as the best alternative to the recommended 6S/6000mAh . It will only be used for cruising and photography as an alternative to my Mavic Air. The aim was to make a quad that would do a similar job to the Mavic but be easily upgradeable and repairable. In my innocence I started out with a 4" GEPRC Elegant and soon ran out of room for equipment. The two frames are like comparing a Porsche 911 to a Mack semi trailer. :D Merry Christmas Pawel and thanks for your help.
Perfect, Pawel. 😊 That's why they're using LiIon packs only for smaller and and really efficient quads like the 4" long range ones. 😊 Happy holidays! And stay safe there with your family! 🖖😊
don't forget the lower voltage i fly a ranger 2000 and had to up my kv from 1250 to 1400 to have any power when the li-ion gets below 3,7-8 v (home made 21700 3s-2p)
would a 3s li ion for a 1400mm skysurfers (bixler type) with 6 inch prop be good enough taking into account that it has flaps and a speedebee mini with GPS?
Hi Pawel! For an airplane, what do you think, if we use a small Lipo and a li-ion pack in parallel? The lipo will compensate for the high current demand at the launch and the li ion will do it's job for the rest of the flight?
I'm waiting for someone to exploit the inherent mechanical strength of these cell and build the fuselage and the main spars out of them so that the battery is the frame of the plane. Should work if you figure out the connectors so that they don't become the weak points.
Hi~ Let me ask you a question. It's a 3 inch cine hoop. In the video, there are videos of making a pack with 4 lithium-ion 18650 batteries and flying it with an FPV long range. With excitement, I ordered batteries and made a pack. LGDBHG21865 3000mA. The problem is... When I hovered, the yaw tick symptom reappeared after it came up, and, after a few seconds, the low-voltage buzzer sounded and the aircraft sank. If I open it again, it opens again,,,,, repeat... So, I changed the low voltage warning in Beta Flight to 2.7V, and when I turned it on, there was no sound. If I take a break for a while, it will float again. But it sinks again... The battery is hot, and the voltage is 3.8V... TT I bought 40 tablets... but I can't use them all? How do people use? Batteries were also made by buying anything. Is my FC the problem? Or is there a special setting for Li-ion? FC is IFlight SucceX Mini F4 V3 Stack, and the manual says 2~6 Lipol. Do I have to use only Lipol? Can I change FC? Why is this happening? It's a waste of money/work time. I'm serious~~ Please advise.~~ TT
i run a 5s1p samsung 40t 21700 4000mah. they have 35a constant draw rating. i run it on the project399 super g+ and get 18-20 of flight time, cruising w/7". they are $6 a cell
I've tried 4s1p vtc06 on 5inch and frankly it has a lot of downsides. Have to deplete to 2.5v if you want all 3000mah, sag is real, motors react with reduced sharpness on FC commands, oscillations are more prominent and generally is meh.. I get more time from 4s 1.5ah tattoo 95c. Otherwise liIon rules on my planes one with 4s2p 5000mah INR 25R, other with 3s 3000mah vtc06, swappable for 2500mah 3s INR 25R. Have to say Samsung's are better than vtc06 despite 500mah difference and "higher c rating".
For most drones I agree. For most planes, I think there are a lot of advantages. The main downside is that it is a big weight commitment to move from a smaller lipo to 18650.
"similar weight but twice the capacity"... Well if you want to sell Lions that sounds promising but I think here is something wrong. capacity does not count unless you compare it with the same voltage. But Li ion vs lipo do not have the same voltage. So if you compare the stored energy the advantage is far from twice as good. In fact if you compare the energy densities they are very close www.epectec.com/images/battery-comparison-energy-density.jpg The fact that makes lipos heavier is the posibility to create large cathodes for high discharge rates. So imho you cannot compare a 130C Lipo to a Lion. If you go to a 5-10C Lipo with the advantage of well manufactured design , more stable voltage and safer use the whole advantage shrinks. At the moment I am calculating and measuring the options for a bigger long range drone. And yes the weight of a lion would be a little less. But not even near 50% that justifies a Lion over the disadvantages..Maybe I miss something at the moment...lets explore this further
Hello, there is an also Polish guy who flies EDF jets on 21700 Samsungs LiIons ("EDF rc jet" I think is the name of his channel). It would be interesting if you can share your thoughts about pumping around 80A of such a chemistry.
@@FPVUniversity That makes sense. I've watched all these vids lately about the wonders of Li-Ion batteries. Only you came to explain the technical differences between both types. Much appreciated!.
I just bought an Arduino Spot Welder few weeks ago and built an 4S3P pack with Sanyo NCR18650GA 3350mAh cells, so theoretically is a 10AH 4S with 30Amps max value. It weights over 1kilo! However I didn't test it yet due to bad weather. I have an Mini Talon wing that should work ok, and a 7 inch kwad ... that I think will struggle a lot with.
I was wondering can I maybe have two packs on my drone paralel? One would be li-po to have big current when needed and second pack with li-ion to increase capacity. But I will need to invest probably in 7 inch drone before testing this approach. :-/
Pawel - Great video and discussion of the good&bad of using Lion batteries. Do you know if there is a common cell smaller than 18650 that could be used to make packs? I was thinking that could keep the weight down for using a 2P configuration. Or would a smaller cell also have a lower max current rating making it no benefit?
why do you keep saying Lithium when referring to 18650s? LiPo is also Lithium.... LiPo = Lithium Polymer. Don't you mean Lithium Ion? Really grinds my gears....
I'm trying to reduce sag in my build by increasing the wire gauges and reducing the battery leads length. Is there something else that causes sag? I might try replacing the motor wires with a higher wire gauge as well, but I don't know if that will have any effect on the voltage drop.
THANK YOU FOR SHARE INFORMATIONS I have ldark et115. DO you think will work with 2s 18650. THE proos are 2.3 inch and original battery is 550mah 80c. WANT for cruize not acrobatics. TOTAL weight of quadcopter+ battery is 125 grams. I GET now 3 min fly time.😥😥
I think there is a strong argument for using 8s1p vs 4s2p. Any efficiency you can get at higher power levels is good. Keeping the current down keeps everything cooler and more efficient so you can squeeze things a bit harder.
@@JS-op5gk I thought it only allowed you to run smaller diameter wire for the same current. As far as I know, 8s with the appropriate prop is going to draw more current than 4s with the appropriate prop but maybe I'm wrong.
@@henryknox4511 For a given wattage 8s will be half the current of 4s, most of the heat build up is down to current not voltage. Reduce the current, reduce the heat in the wires, the esc, the motor. At 5-10amps that's less of a factor but if you are trying to pull 20A at 8s voltage vs 40A at 4s voltage then it starts becoming more significant. Just in terms of the motor alone this is a big deal, 40A vs 20A is going to make a huge difference for how hot a motor gets which directly affects it's efficiency.
I'm sceptical. Different capacity, different internal resistance and different discharge curves. Probably possible with extra electronics that would have to handle high current, be heavy and expensive
@@FPVUniversity what if it was possible to top off a lipo set with Li ion set. Like how you can charge batteries from batteries? So as you are flying it's feeding capacity over to the lipos.
I used a Li-on 4s 3000mAh on my 7" ...it couldn't take off higher than a metre before cutting out.My motors were 1500kv,..Total shit is my opinion.Gave up with Li-Ons. Probably great for 4" long range lightweight kwads👍😉
Then you are doing it wrong. I have been flying 7in with 6s2p for over a year and flying up to 23minutes. And my 10 inch on 6s2p flys beautifully. Sony VTC6A or VTC5D.
@@dividingbyzerofpv6748 .. Interesting!. Yeah something must have been wrong.Maybe I forget to drop the Betaflight "minimum cell voltage" to 2.5 volts?. Can't remember now,twas last year.
Answer is clear.
Li-Po-->Racing/Freestyle (Performance)
Li-Ion-->Long Range (Endurance)
Its only true, if u dont need some amps. Im flying a 4m electro powerd sailplane. i need endurance and long fly times - but at the start, i need at least 90 amps. so its not useable. thats what u have to be different. depends on the real plane - not only if using a copter or a plane - or using racing or long range.
u have to know your max possible amps drawing - no matter of what u flying
Great video as always. I would just add that the surge in battery wholesalers in the past 2 years has really changed the economics. For example, you can get LG MH-1 or 18650BD cells with 3.2Ah and 10A continuous for about 1.50 USD each. Lately "salvage" means never used because companies go bankrupt before even selling one scooter or bike. So, a 4s2p is maybe 13 USD with wires and heat shrink and is good for maybe 4 times the charge cycles of LiPo. Another advantage of LiIo is configuration. You can pretty much make the pack any shape you want. Center of gravity off? Form a 4s tube that runs the length of the craft. Only have an "L" shaped space left in your bay? No problem. Lastly, with balance equalizer boards, you can say goodbye to balance chargers and hello to 24/7 cell balancing, including during flight, at any discharge level. In other words, LiIo looking better every day.
link to store please; sounds awfully cheap
@@FasterThanJesus666 Battery Hookup or Jehu Garcia
@@tedhancock68 nice one mate
Facts bro I flying a 5 inch nicely on 4s
Been flying 18650 VTC5D as my preferred cell and VTC6A for almost a year now. Primary pack is 6s2p configuration for 7in on 2806.5 1300kv Avengers or 10inch on 3115 640kv motors.
Can very nearly rip quite nicely on 3s VTC5D packs with 3600kv 1406-1506 sized motors and 3.5in triblades. Best to have an amp meter so you can use Betaflight to run up your motors tab and see at what throttle you hit 15 amps and 25 amps. Then make sure you have throttle % active in your OSD because many of the small budget 4:1 escs do not have a current sensor so go by throttle % instead.
Have also run two packs for 6s4p on 13inch Xclass cruising for 18 minutes at a constant 50mph. Soon will have 4 sets of 4s2p built for 6in drones but used for paralleling and series for 8s4p on the Xclass becase it really wants 32v instead of 24.
You ever should keep in mind when using liion. Due to the voltage drop you should always add 1cell. So if you're using 4s, with liion you take 5s and you're fine.
For high current use vtc6 with 3000mah, for lower current use GA series with 3500mah.
Interesting theory.... would you care to share??
@@Migueldeservantes No I won't, how could I help you?
I can confirm. My Samsung 40T have about the same voltage as a good 5s Lipo with 6s under load. But with about 50% more capacity.
@@Migueldeservantes better to think of it as driving down current draw as you increase voltage.
Consider 800 watts needed to fly.
At 2s and 8 volts you are doing 100 amps. Versus 4s and 16v you are doing 50 amps.
Are those the actual values? No. But it shows how a build in 4s could sag your batteries more than the same build on 6s, voltage drives down amps.
Then if you need more amps build in parallel. I figure my 6s2p packs are good for a solid 30 amp continuous discharge with a 60amp burst. VTC5D and VTC6A cells should be considered 15 amp continuous at best and 30 amp burst for short duration.
Dude I really really like your videos. I started a Inav adventure with a 7” build about a month ago and watched many of your videos to build it . Maiden on Sunday went perfect . 9 minute flight time on 4s 1500 lipo 3.8 per cell after rest . 20 satellites. I was too paranoid to try RTH or position hold but everything else worked . Very stable and easier to fly acro then stable mode . Now of course it’s time to build some 18650 packs.
These cells are great for many applications. The current limitation does make it tricky for hobby use though. Since the only real way to lower current for a given vehicle is to add cells either increasing voltage or running them in parrallel, either way you need more cells. For a flying machine that means more weight and space needed as well as cost. This quickly takes us past the point of diminishing returns. However, if you do run parrallel packs you really up your capacity. So a carefully planned craft could yield great results in terms of flight time. I just purchased some sony 30a rated cells to mess around with but they are NOT cheap for the real ones. It's going to be hard to beat lipo for the time being.
Cheers
I'm using 4S3P battery (Molicel M50A cells) on my 2m Opterra. Gives me over an hour of cruise time with a comfortable reserve.
BTW thanks for the tip on the soldering acid!
I'm using 4S3P Samsung 50E on my Opterra 😋
yo una 4S3P (celdas Murata VT6A), mañana lo probaré, estoy ansioso
Thank you for contributing to the advancement of this hobby, as always, keep up the good work.
Good video, Paweł! Thanks!
From experience using a 4S1P Sanyo GA (alternatively LG MJ1) on the Z84 during takeoff it does take more than the max 10A (as per spec). This, however lasts only for about 5-7 seconds because the moment the plane starts moving the strain on the propeller decreases rapidly as soon as the air starts moving through it. Using autolaunch is even better because the moment the prop starts the plane already is moving forward and thus the time the battery experiences high drain is even shorter.
I also use a 3Ah HG2s (20A) on my 250mm miniquad and I get around 15-18 minutes of cruising (no aerobatics!). The pack really weights a lot less than the 3Ah 2S lipo that would make the quad unflyable.
I use 21700 45A molicell 6s1p on my 6" cinematic with a great performance draining 20/25A without getting hot cell's
I built a Samsung 21700 T40 pack and it's working great as well. 4000 mah is giving me 20+ minutes of cruising. Just don't slam the throttle.
@@gattmolson same for me, good sweet spot the pawel did not think about
No one talks about the charge times for these things though... You need to set them round 1.5a charge rade doubling your typical charge times frequently timing out the charger lol. Not that it's a huge deal breaker.
But it's often neglected to mention that while you can discharge them lower you don't really get a load of useful power as it doesn't have punch to keep you flying normally..it's safe in that you can fly longer but once you start to feel the sag you'd best start heading home to land.. you can cruise back home and not have to worry about destroying the pack though that's great.
the "punch" is derived by the maximum continuous discharge is it not? so if your 18650 is 3 amp yeah you arent gonna get any punch
@S Grim they are good packs you just have to know what you're getting with them and how to fly these packs the higher discharge versions are more expensive and some reviewers actually use the low discharge ( c rating ) when discussing them this gimping the review. They can be good just have to pick the right one for your exact application. I'd only wanna use them for cruise or long range and again you have to know exactly when to turn back
Tesla's new cylindrical cells are pretty impressive, they modified the construction of the cell to avoid all the current going through small tabs, allowing the cell to dissipate heat more efficiently and reduce ESR. I expect these cells, with the right chemestry, to perform on-par with pouch cells (what everyone in this hobby calls "LiPo" (for the record, they both have polymer separators, but there are many dozens of lithium chemistries out there that are subsets of lithium ion. the high performance 18650's use INR.)
The new 4680 cells are also massive and super heavy so you'll need a big plane or drone to even fit a 4s1p pack.
@@avsaase I do hope someone takes the idea and applies it to 18650's. I doubt it will happen because Tesla patented the idea and probably have the patent for this process applied to 18650's as well, even though they will not benefit from this (unless they begin manufacturing 18650s to sell to an open market)
I doubt they would sell 4680's either, they would need to be salvaged. I think 4 to 12 of them would be excellent for a 7" to 10" build!
Got to keep the cells happy ;-) Thanks for the information Pawel.
Robisz niesamowitą robotę dla całej społeczności FPV. Dziękuję, że dzielisz się swoją bezcenną wiedzą. Gdy ktoś nowy pyta mnie o źródło wiedzy w temacie, zawszę linkuję Ciebie i Bardwella. Pozdrawiam!
We need affordable and compact high voltage escs handling 8s or 10s and combine with low kv motors, so we can keep current low, and use thinner wires etc. The Molicell 21700 are very good also
I'm testing the Samsung 21700 40t. In the Fms cessna the average consumption is 15A and peaks of 20, with very little power drop compared to lipo.
I have tested a 40 A discharge bench and they can withstand them but with more pronounced power drops and high temperatures. I think it is a good alternative in motorsailers.
Use the Samsung 30t. More power. 35A. Burst Up to 60A
Combination of the regular Lithium batteries with supercapacitors may be the best of both worlds. Weight and storage may have some challenges but the good news is that the supercaps are very light Weight and carry a good punch like for take off like a chock absorber for the batteries so that the up front current is provided without over straining the batteries. I used this method on solar backups to help with things like air-conditioner compressor kicking in and it seems to work great. Just an idea I am sharing. It may make a nice experiment using drones.
Well stated Pawel, for wing cruiser LiIon 18650 are cool. I can fly 45 minutes plus with the mini AR Wing cruising 60+kmh on 3s Sony VTC6. Launch no issue using iNav autolaunch,
The miniwing's motor takes only 10A at full throttle so it should be easy. I bought a 3S liion from ZOHD but it is too tall! :/ So I've just purchased a ZOHD Dart 250g which should have more room. I'm a bit worried about the launch tho. It has a smaller motor than our AR miniwing... Gotta throw hard!
I think it would really interesting to see li-ion cell with tesla tabless design. It should be much capable to dump large current, without being constrainted by the narrow tab in cell battery.
But we probably won't see it in years because of tesla holding the patent.
wow i wanted to see a vid like this for a while now, ty pawel for a great vid and great awesome content
my pleasure mate!
I currently use Li-Ion (18650 and 21700) unless I need very high currents in which case I go Li-Po.
I like the idea because there are INR Type of cells they are allow 30A Constant current.
So a 4S2P Pack would deliver 60A Current wich should be good for easy flying.
And we are Talking about 7Ah 4S and 580G weight.
Li-fe is also interesting because of the long Cycle life wich is 5-10 Times more than Li-Po
Li-FePO4 is much lower energy density in size and weight they're good for replacement with standard lead-acid ones. But not for drones even Electric vehicles.
Can you use a supercapacitor to help with the takeoff and cruise on li-ion to get the best of both worlds?
Nope! you can use a long wire with a magnetic connector (lol, good luck finding one rated at 60A) or a small capacity lipo in parallel.
Thanks Pawel, your video came out just in time!
I fly bigger EDF jets and I power them with Molicel P42A cells. Their specs state 45A max discharge, so I always use 2 in parallel and add more cells then a LiPo setup would have.
My Freewing Avanti can go 220kmh+ and still have a 5min+ flight time.
There are some tradeoffs - one needs to drill holes for cooling and wire multiple packs properly (I use 10S2P with 6S and 4s packs)
When Molicel releases the the P45B cell then it will be a total no-brainer to use these over Lipos ;)
Hi Adam, I noted your reply regarding bigger EDF jets. I am currently (no pun) using 6S 4000 75C lipos to power a 90mm EDF, which draws 110A full throttle. I read "I always use 2 in parallel and add more cells than a lipo setup". Do you mean add series cells? Change 6S to 7S ?? Are there any other brands, with equivalent performance?
Happy flying 👍
@@davidwatkin1484 At the moment Molicel P45B is the best li-ion cell, I am not using P42A anymore even ;)
Just google the topic of "connecting cells in series and in parallel"
Takiej informacji szukałem. Dziękówa
The one big issue I have with 18650 cells...is that they only come in one physical size/ capacity....18650.
This is why the 4 inch LR quad is designed around 4 X 18650 cells.... Very limiting.
South a great video. Once again very very thank You for sharing Your knowledge.
Glad you enjoyed it
My experience: 5" slim frame, full Gopro8, 2550KV 5S motors, 5.1x3.1 props, LiIon 6S pack 3150mAh: hovering/slow cruise (first test) flight time 25minutes. end voltage 2,5V (sum 15V at the end)
how much did it weigh AUW? What thrust to weight can you get to before the amperage goes too high?
@@warrenrose6362 820g. it has some oompf and stays stable at the end. ratio? dunno
Some good information. And some useful tips . BUT VERY LONG DRAWN OUT TO THE POINT. AS A EXPERIENCED HOBBYIST. TO BEGINNERS IT COULD CAUSE THEM A LOT OF CONFUSION. BUT APPRECIATE YOUR INFORMATION.
Now I understand why Zipline Drones use a catapult for takeoff
Will there be a followup ? Tips for building Liion? Yes, the soldering video is out there but soldering isn't the whole build
Btw.: Good overview
I use 21700 cells more than 18650. One thing I wish iNav had was a preset for liion for battery profiles. I run both lipo and liion in my planes and have profile. Would be nice if in the configurator you could choose battery type along with the battery profile.
In your battery profile on INAV you have all the characteristics needed I believe (max voltage, min voltage and in between warnings).
I use 18650 only for my googles,2s or 3s...tnx for comparison
It looks like the 7" GEPRC Crocodile I'm building will get 8 cell Li-Ion packs in series/parallel 4S configuration as the best alternative to the recommended 6S/6000mAh . It will only be used for cruising and photography as an alternative to my Mavic Air. The aim was to make a quad that would do a similar job to the Mavic but be easily upgradeable and repairable. In my innocence I started out with a 4" GEPRC Elegant and soon ran out of room for equipment. The two frames are like comparing a Porsche 911 to a Mack semi trailer. :D
Merry Christmas Pawel and thanks for your help.
The problem with 8S is that there is very little hardware that can handle that. ESCs, BECs, even motors with low enough KV
Perfect, Pawel. 😊
That's why they're using LiIon packs only for smaller and and really efficient quads like the 4" long range ones. 😊
Happy holidays! And stay safe there with your family! 🖖😊
don't forget the lower voltage i fly a ranger 2000 and had to up my kv from 1250 to 1400 to have any power when the li-ion gets below 3,7-8 v (home made 21700 3s-2p)
would a 3s li ion for a 1400mm skysurfers (bixler type) with 6 inch prop be good enough taking into account that it has flaps and a speedebee mini with GPS?
This is very very helpful thank you very much.
Hi Pawel! For an airplane, what do you think, if we use a small Lipo and a li-ion pack in parallel? The lipo will compensate for the high current demand at the launch and the li ion will do it's job for the rest of the flight?
pratik bhai ... did you try it ???
i want to know it
I'm waiting for someone to exploit the inherent mechanical strength of these cell and build the fuselage and the main spars out of them so that the battery is the frame of the plane. Should work if you figure out the connectors so that they don't become the weak points.
Interesting idea, but it would make the fuselage one time only :) Plus, balancing would be a hell more complicated
Hi~
Let me ask you a question.
It's a 3 inch cine hoop.
In the video, there are videos of making a pack with 4 lithium-ion 18650 batteries and flying it with an FPV long range.
With excitement, I ordered batteries and made a pack.
LGDBHG21865 3000mA.
The problem is... When I hovered, the yaw tick symptom reappeared after it came up, and, after a few seconds, the low-voltage buzzer sounded and the aircraft sank.
If I open it again, it opens again,,,,, repeat...
So, I changed the low voltage warning in Beta Flight to 2.7V, and when I turned it on, there was no sound.
If I take a break for a while, it will float again. But it sinks again... The battery is hot, and the voltage is 3.8V... TT
I bought 40 tablets... but I can't use them all?
How do people use? Batteries were also made by buying anything.
Is my FC the problem? Or is there a special setting for Li-ion?
FC is IFlight SucceX Mini F4 V3 Stack, and the manual says 2~6 Lipol. Do I have to use only Lipol? Can I change FC?
Why is this happening?
It's a waste of money/work time.
I'm serious~~ Please advise.~~ TT
i run a 5s1p samsung 40t 21700 4000mah. they have 35a constant draw rating. i run it on the project399 super g+ and get 18-20 of flight time, cruising w/7". they are $6 a cell
I've tried 4s1p vtc06 on 5inch and frankly it has a lot of downsides. Have to deplete to 2.5v if you want all 3000mah, sag is real, motors react with reduced sharpness on FC commands, oscillations are more prominent and generally is meh.. I get more time from 4s 1.5ah tattoo 95c. Otherwise liIon rules on my planes one with 4s2p 5000mah INR 25R, other with 3s 3000mah vtc06, swappable for 2500mah 3s INR 25R. Have to say Samsung's are better than vtc06 despite 500mah difference and "higher c rating".
For most drones I agree. For most planes, I think there are a lot of advantages. The main downside is that it is a big weight commitment to move from a smaller lipo to 18650.
"similar weight but twice the capacity"...
Well if you want to sell Lions that sounds promising but I think here is something wrong.
capacity does not count unless you compare it with the same voltage. But Li ion vs lipo do not have the same voltage. So if you compare the stored energy the advantage is far from twice as good. In fact if you compare the energy densities they are very close www.epectec.com/images/battery-comparison-energy-density.jpg
The fact that makes lipos heavier is the posibility to create large cathodes for high discharge rates. So imho you cannot compare a 130C Lipo to a Lion. If you go to a 5-10C Lipo with the advantage of well manufactured design , more stable voltage and safer use the whole advantage shrinks.
At the moment I am calculating and measuring the options for a bigger long range drone. And yes the weight of a lion would be a little less. But not even near 50% that justifies a Lion over the disadvantages..Maybe I miss something at the moment...lets explore this further
Great info, thanks! How about the 28650? (For bigger drones)
well done!
Really helpful. Thanks man!
Super przydatne informacje, dziękuję i pozdrawiam!
Best battery: Samsung 30t. 4s about 300gr.. discharge 35A. Burst Up to 60A
Hello, there is an also Polish guy who flies EDF jets on 21700 Samsungs LiIons ("EDF rc jet" I think is the name of his channel).
It would be interesting if you can share your thoughts about pumping around 80A of such a chemistry.
I'm flying 40T samsungs on a 7 inch quad and occasionally pull over 40amps, but nothing like 80
With a 4s2p or just single pack?
@@Bj0rnis with different setups from 6S to 12S and 2P or 3P
@@Bj0rnis single
Yeah, I was wondering why the interest in Li-Ion batteries suddenly grew the past 2 years. How come no one thought of this before?
It just got affordable I suppose. And you need a good li-ion cells to make that work
@@FPVUniversity That makes sense. I've watched all these vids lately about the wonders of Li-Ion batteries. Only you came to explain the technical differences between both types. Much appreciated!.
I just bought an Arduino Spot Welder few weeks ago and built an 4S3P pack with Sanyo NCR18650GA 3350mAh cells, so theoretically is a 10AH 4S with 30Amps max value. It weights over 1kilo!
However I didn't test it yet due to bad weather. I have an Mini Talon wing that should work ok, and a 7 inch kwad ... that I think will struggle a lot with.
I made exactly that, 605 gram total.
@@13FPV yes, on a second look mine are about 600ish grams also, I can't wait to try it out!
lol, i also thought what the Fak, 1 kilo? hahaha
I was wondering can I maybe have two packs on my drone paralel? One would be li-po to have big current when needed and second pack with li-ion to increase capacity. But I will need to invest probably in 7 inch drone before testing this approach. :-/
yes, absolutely. You can connect 2 packs in parallel and it work just fine
Pawel - Great video and discussion of the good&bad of using Lion batteries. Do you know if there is a common cell smaller than 18650 that could be used to make packs? I was thinking that could keep the weight down for using a 2P configuration. Or would a smaller cell also have a lower max current rating making it no benefit?
Holy crap when I saw the pic on the video I thought it was Bardwell, I was wondering why I never get notified for this video xD
Nope, it's me :)
@@FPVUniversity thank you for the information! Very helpful!!
So unless you are flying a 7" cruiser class quad or plane stick to LiPo?
why do you keep saying Lithium when referring to 18650s? LiPo is also Lithium.... LiPo = Lithium Polymer. Don't you mean Lithium Ion? Really grinds my gears....
Lightweight Sony vt5 2.6A. Discharge 20A burst Up to 30A. 4s. About 200gr..
Do you have to storage discharge li ion batterys like lipos?
Hi Pawel, what do you think of the promiding protocol Express LRS to recycle the R9 gears ?
I'm trying to reduce sag in my build by increasing the wire gauges and reducing the battery leads length. Is there something else that causes sag?
I might try replacing the motor wires with a higher wire gauge as well, but I don't know if that will have any effect on the voltage drop.
THANK YOU FOR SHARE INFORMATIONS
I have ldark et115. DO you think will work with 2s 18650. THE proos are 2.3 inch and original battery is 550mah 80c. WANT for cruize not acrobatics. TOTAL weight of quadcopter+ battery is 125 grams. I GET now 3 min fly time.😥😥
Is li ion hard to control throttle? Im learning hover with li ion battery is so difficult..
You just have to be very very very gentle with the throttle. No sudden movements :)
@@FPVUniversity too many very 😅
Why not hook up a lipo and a li-ion both in parallel 🤔
I'm not sure what would be a benefit of that. I think it might rather combine weak sides of both chemistries than supress them
I think there is a strong argument for using 8s1p vs 4s2p. Any efficiency you can get at higher power levels is good. Keeping the current down keeps everything cooler and more efficient so you can squeeze things a bit harder.
Are 8s ESCs aviable in a normal pricerange?
How is 8s more efficient than 4s?
@@henryknox4511 mayby via internal resistance? I'm not sure though. Was wondering,too
@@JS-op5gk I thought it only allowed you to run smaller diameter wire for the same current. As far as I know, 8s with the appropriate prop is going to draw more current than 4s with the appropriate prop but maybe I'm wrong.
@@henryknox4511 For a given wattage 8s will be half the current of 4s, most of the heat build up is down to current not voltage. Reduce the current, reduce the heat in the wires, the esc, the motor. At 5-10amps that's less of a factor but if you are trying to pull 20A at 8s voltage vs 40A at 4s voltage then it starts becoming more significant. Just in terms of the motor alone this is a big deal, 40A vs 20A is going to make a huge difference for how hot a motor gets which directly affects it's efficiency.
Is it possible to make a hybrid with i.e. a 4S LiPo and in parallel a Lithium Ion.
I was thinking the same thing. The lipo could handle the burst. Would love to hear from the experts on this.
I'm sceptical. Different capacity, different internal resistance and different discharge curves. Probably possible with extra electronics that would have to handle high current, be heavy and expensive
@@FPVUniversity what if it was possible to top off a lipo set with Li ion set. Like how you can charge batteries from batteries? So as you are flying it's feeding capacity over to the lipos.
@@jeffjorczak You would have to limit the charging current etc. etc.
Is a li-ion not the perfect solution for Cinewhoops? (Next to 7" cruising)
I was wondering exactly the same thing 🤭
Please spot weldbsokder ruin your cell
Siema Pawle 👊😃👍
XT60 or XT30?
For 7" long range is lipo better
fml i thought you were bardwel haha
I used a Li-on 4s 3000mAh on my 7" ...it couldn't take off higher than a metre before cutting out.My motors were 1500kv,..Total shit is my opinion.Gave up with Li-Ons.
Probably great for 4" long range lightweight kwads👍😉
What cells did you use? My LIthium Ion pack is working great on my 7 inch. Cells are 40C and I usually pull 5-10 Amps flying around.
@@gattmolson Oh..I bought from Overlander,..they say they make the 4 cell pack using Samsung 18650,s but they don't specify the model.
Then you are doing it wrong. I have been flying 7in with 6s2p for over a year and flying up to 23minutes. And my 10 inch on 6s2p flys beautifully.
Sony VTC6A or VTC5D.
@@dividingbyzerofpv6748 .. Interesting!. Yeah something must have been wrong.Maybe I forget to drop the Betaflight "minimum cell voltage" to 2.5 volts?. Can't remember now,twas last year.
Lipo it is for now then...my aircraft are pushing 30 plus amps at take off
Thus launchers are also becoming more popular.
Imagine an hybrid battery containing a small lipo just in case and for launch. Probably too complex and costly...
Just use rubber band to lunch your planes. You will have lighter amp punch.
Ahhh so stop with the flippedy floppedy on drone!! And learn flippedy floppedy on airplane
Bro write the numbers, more figures less talk.
Man i dont understand what ur saying. Say liion or lipo not just lithium. I dont know which battery ur talkong about when
Man, that sucks