Should you be using Lithium-Ion batteries on your FPV drone?

[@GiantAntCowboy]

IMPORTANT: Make sure to calibrate your Current Sensor. The Amp reading is often inaccurate and it’s a very important metric when using Li-Ion packs.

[@3dxyz412]

How accurate is accurate? Which brand of sensor is the most accurate?

[@GiantAntCowboy]

@@3dxyz412 it’s impossible to get perfect because there’s a lot of variables... So I always calibrate my sensor so the Current (Amps) & mAh Used display are slightly higher than actual. This is the safest way to do it. With a couple tries you can usually get it within 5% of actual. Basic Process: Fully Charge a Pack, Fly/Drain it, Note the mAh Used, then Charge the pack & Note the mAh Hours Charged. The difference between the Used & Charged is what needs to be calibrated. Oscar Liang has a good write up in the Calibration Process with the calculation used to set the amount. Note: Also check your Voltage Readings. This is easy & usually pretty accurate, but Current (Amps) always needs to be checked & set.

[@Imakilln]

@@3dxyz412 Every single quad current sensor I've measured has been noticeably out, usually ~10-20% - some worse than others (iflight ESC's especially). The answer is to calibrate your quad so that it generally slightly OVER reads so that you always 'think' you've used a little more than you actually have & to account for Internal resistance losses. If you don't have access to an accurate meter you can 'calibrate' it to what your lipo charger recharges - fly a pack, note the mAh reading, charge, note the mAh reading then adjust current calibration up/down until readings are fairly close. Note charging a battery ALWAYS adds more energy to the pack than you discharge.. This also assumes your charger is accurate which is another story XD

[@Filipniak]

Funny after watching this video this question came up on my mind and I was just about to ask about it here, because that's quite often my main source of information in terms of how much battery I have left. I honestly was pretty sure this measurment is very accurate. Thanks for that advise, now I'll do some tests, especially now when I'm flyng iFlight quad. Thanks guys!

[@GiantAntCowboy]

@@Filipniak yea, most FC/ESC stacks actually give you a calibration number to use in BF; but most people probably never even noticed it, and honestly for most people super accurate Current readings isn’t that important. If you do longer-range flights, and/or use Li-Ion packs, it’s always best to do some calibration checks yourself. Having an accurate number will help you avoid running out of battery, or pulling too much current & frying the battery! Note: Though Current & mAh Used figures are helpful guides, it’s also extremely important to watch Per Cell Voltage because you can judge the true health of the battery by watching the Voltage. Over time batteries get weaker & lose capacity, so if you only focus on mAh Used as a fuel gauge you might get an unpleasant surprise one day!

[@HermyH66]

Li-ion has been the nr.1 choice for long range rigs for years.

[@Tomcat2_kanal]

My friend is making his own Li-Ion packs from single 21700 battery cells that he is configuring according to his needs for his long range drone. Good thing about it is he can adjust the cell pack shape for the particular drone as he needs and also he can adjust the capacity based on how long he needs to fly...

[@ryanisacuc8381]

He should make a video or post on how to do it

[@theshazman]

I make my own 4S Li-Ion packs out of Murata 18650's. Slightly heavier than LiPo 4S but I can fly my 4" with a naked gopro for 25 minutes on a good day. I fly cinematic/exploration and long range so it's perfect for me. 6S Li-Ion on a 7" is absolutely bonkers, I think I got up to 40 minutes in one test flight.. with some juice to spare.

[@illicit_fpv8208]

You're a brave man. I won't even punch out my 6" on molicel 6S packs. It's not hard at all to hit 60-70 amps

[@TheParadigmShiftTV]

I fly the same GEPRC 6000mAh Li-Ion packs with my Chimera 7 V1 & V2 quads. They're great for long range cruising. They get me up mountains.

[@luastoned]

If your amp reading is somewhat right, you are pulling beyond 100A from a 2P configuration, no 18650 cell is rated at or above 50A. Long range FPV usually does not exceed those ratings so it makes way more sense there.

[@MJ-bj1gn]

Congrats on the 300k subs, jb. 🎉 16:17 I don't quite agree with your choices. Most Li-Ion packs (4 or 6S1P) have a max discharge rate of 30-40A, depending on if they're using 18650s or 21700s. So even if you never exceed ~60% throttle, you will still hit the 30/40A rating of the battery (meaning that the battery gets hot and damaged). I've noticed that on my 7" when I when I exceed about 50% throttle the battery gets hot. Which is why I only recommend using LiIon packs on very efficient multicopters (like the Rekon line of quads) or on fixed wing aircraft

[@maro0016]

A “popped” one about a year ago, be careful 😉

[@CricketyChris]

8s FTW

[@saturn_fpv]

@MJ-bj1gn This is a 2P pack, that's why double the amp draw is possible.

[@maro0016]

@@saturn_fpv I had issues on a rekon 6, with I3 (no GoPro) on a geprc 3000mah 6s pack with original 2blade props. I think I used the pack before about 20 times -> it could’ve been also wear …

[@dividingbyzerofpv6748]

3000mah shows it was a straight 6s1p arrangement, yes tbat is gonna be problematic. 6s2p is the minimum I would want in combination with 7in or 10inch quads. I was very impressed with a 10in using 3115 980kv motors with 6s2p. If built for a pair of 4s2p pacls in series for 8s2p the thing would have outright ripped. That is one of places I left off when I backed off of building 4 years ago

[@fpvkabo]

I maxed out my ardupilot 6" to 2.233 v/cell before bringing it down from poshold running (hover test only) for 32min. on a homemade 3s battery using 21700 lion cells.

[@GiantAntCowboy]

Nice to see Bardwell touch on Li-Ion packs. I’ve been flying them exclusively on my 7” quad for years & here’s some additional thoughts: *Warning* Not a Popular Opinion, but Soldered packs perform much better than Spot Welded Packs. The reason: Welding requires the use of metals with High Resistance. Nickel is generally used, but Copper is 4x better at conducting electricity, so you get less sag & batteries stay cooler/last longer. Unfortunately all retail packs use thin nickel strips, so you’ll have to DIY to have copper packs. DIY isn’t hard but takes some basic knowledge & patience so you don’t overheat things… I’ve thought about doing a comparison but retail packs are 2x as expensive as DIY packs. For those curious; here’s a super stressful Li-ion tests in the mountains: kzbin.info/www/bejne/nam2l3dsha1khpI And here’s a very detailed comparison of various li-Ion setups: kzbin.info/www/bejne/qKrRnKuVhL6HfKs Definitely a great “tool in the bag!”

[@PhonesandDronesRepair]

When soldering Li-ion cells you need to be very careful. They're particularly sensitive to heat so you need a good iron with a large tip. The surface of the cells also needs to be prepped well. I would use very high grit sandpaper (1000+) or scotch brite then immediately coat with flux. You also need to solder very quickly, not more than a couple of seconds. -HereComesWhitey ;)

[@dividingbyzerofpv6748]

Sony VTC5D seemed to be the best cell available. Gave up some capacity but gained back amperage available. Tried some larger dimention "high amp" batteries and they proved not worth it.

[@GiantAntCowboy]

@@dividingbyzerofpv6748 my favorites are Molicel, especially the P28a for 18650, or P45b for 21700. Have you tried these?

[@GiantAntCowboy]

@@PhonesandDronesRepair hey bud, 100% accurate. Prep & Time are key. It’s usually takes my two rounds of soldering. Soldered a dozen packs and all turned out great. Glad you mentored this, people must do research and use caution. cheers!

[@alpenfoxvideo7255]

at what voltage do you land your drone? I have a pair of ion packs but i'm still landing them at 3.3v

[@bendixtrinity]

one more thing to watch out for in li-on is the Amp draw/usage.. that punch out is really brave. xD I wont ever do that to my Li-on so thanks for showing it to me.

[@chriscflint]

I have built a number of Li-ion batteries and the problem with the sag on a punch out is the thickness of the wires/connectors that are used, in your batteries case I would think it is flat metal plates spot welded to the batteries and the square area of those plates will make a difference eg. if they have used 10mm wide by 0.15 thick that equals a 1.5mm square wire. To do 20 amps the wire needs to be around 1.84 sq mm. To do 40 amps the square are is 7.9mm. Clearly difficult to achieve. If people want to build their own my recommendation is to use wires soldered to the battery not the flat plates with spot welding.

[@kaulincurtis9665]

Another option is copper sheet spot welded with nickel on the terminals. Copper is over 4x as conductive as the usual nickel strip used.

[@PhuckenTacoz]

As someone new to flying fpv even though I've had it for a few years this is my kind if battery. Just want to cruise and learn some cinematic videos

[@ThomasDoubting5]

I really like this guy because he knows what expensive is .

[@inakidb]

I had a Auline 3000mA 4S for my long range Roma L5 and I can get the 2.5 after 25 to 30 min of flight. I think Li-Ion will work different if the drone pulls less current than average 5" free style drone.

[@snviper]

I have those in 6S they are very good.

[@spaced-mouse]

just gonna throw this out there, for DIY packs, the Molicel P28a 18650 li-ion are great. max continuous discharge rate of 35a!

[@KitePod]

yes 👍🏻… or for bigger packs the Molicel P45B 21700 cells with 4500mAh and 45A continuous discharge

[@scratchymaster]

​@@KitePodexcept p45b is like $9 per cell, & for drones prolly won't work in 1p.

[@ramus9]

Not just great, they’re the best!

[@dividingbyzerofpv6748]

Lastly. Charge rates. 18650s do not want to see more than a 1C charge rate, some cells even listed .5C. So if you drain a Lithium Ion expect a solid hour or more on the charger to get it back up to full voltage. Even storage is gonna take around 45 min from 2.8-3v

[@kcstocks2004]

They seem like great packs for indoor tours with real estate

[@Mupshot]

My first and second builds were based on liIon batteries. But have since moved to lipo packs

[@prateekchauhan3104]

Tanks to Joshua, now we know the complete layout of his home. ;)

[@jonscot8393]

Only battery I have ever go PUFFY was one of these. So much for the safe ones

[@adamtrzaskowski3901]

I use Li-Ion cells in my big EDF jets ;) You can compensate for the voltage drop, by adding more cells (7S instead of 6S, plus a ESC that will handle that), or getting a 15% higher KV motors.

[@ThatCrazyGardener86]

Thank you for signing that battery, Man 🥰🗽

[@JoshuaBardwell]

Будь ласка

[@mariokotlar303]

Ah, this must be the reason why DJI Avata has twice the battery efficiency than DJI FPV drone. Great to finally understand it, thanks JB!

[@Arek_R.]

When I was a teen in need of money, like 10 years ago, I was making custom LI-ON battery packs like that for forum members from FPV/RC community. But then one guy crashed hard and the whole thing caught on fire and I've stopped doing this to not get myself in some legal trouble. Before that I had plane people tell me they would not need to land to change the battery anymore with my li-on battery and they could fly so long they would land because they get bored or their legs start to hurt, the flight time for planes was like 2-3x longer. I was testing those to be used for FPV quadcopters as well and the results were good for non-racing uses but then I stopped because of the above.

[@piranha1337]

Now test a LiFePo4 for the funsies! Generally a comparison of energy density (Wh/kg) and C discharge rating comparison would be so nice!

[@showdownz]

One is a lipo and the other a lion. You keep referring to the GepRC as a lipo I'll include two time stamps. The first 0:41 clearly shows the GepRC has 18650 and is lithium Ion as its marked Lion The second 1:53 is Bardwell making the slip of calling the lion a lipo. Its an easy slip to make and I expect later in the video this won't happen but I had already noticed this slip a few times by the 1:53 point. Prompting this note.

[@xxxxxxch04xxxxxx22]

Indeed. I kept going back to the biginning out of confusion.

[@SmirkInvestigator]

Totally a li-ion guy. Chill tours and and videography. But I do love a good punchy session. Hypothetically, I didn’t see fitted packs when I looked for them at the time

[@saturn_fpv]

Could've included amp draw on osd after calibration to get an idea of c rate.

[@CorruptName1]

11:30 Although the lion battery is sagging to a lower voltage, it is still less of a sag than a typical lipo if you consider the percent of the usable voltage ranges.

[@pvenzELP]

There is a certain technique when flying li-ion packs. You want to do small smooth movements on the sticks. I've been able to fly for a good 2 miles on low voltage by keeping the throttle at a set position and making elevation changes with pitch changes. If you try to do aggressive punch outs or quick tight turns you'll just crash. It's better to do long , smooth lines with li-ion.

[@spartan3299]

In my researched opinion, FalconRad FPV has the finest methods for building quality Li-ion packs. I have been building packs for a couple years, but I wish I had seen his tutorial first. The way he lays out his balanced lead is perfect.

[@budoskolok]

I am using the home made 21700 lion pack on a 7 inch tricopter. It is cooll :D If you are gentle it can fly

[@Spaniard47]

Concluding that "Li-ion is not gonna give you the same top end power" and will "sag to a lower voltage" than LiPO after testing a single li-ion pack seriously overlooks some important context, even if that is _generally_ true. The Li-ion 18650 cells in this video are the Sony VTC6, a very well respected cell. However, the VTC6 is designed to offer a balance of power and capacity. As such, its 15A max continuous output is a far cry from the 30A rated 18650s which are now commonplace. The Molicel P40B can even hit 40A! In the context of ultra-high power FPV drones, it feels disingenuous not to use cells designed purely for POWER. I guarantee the results would be drastically different than you experienced in this video.

[@dimitarnaydenov90]

Nice I will use lion in 2 scenarios: 1Long range mauntaine cruising with simple freestyle, dives, loops ets.... 2 car chase at a track Both with 7 inch What do you think about that?

[@keithcarpenter5254]

Current draw needs to balanced with battery capacity to get the discharge c rate sensible with lion, thats all. They don't have the ability to dump the same kinds of current as lipos, at least, 18650 sized lions dont. There are some bigger lions that can, but you'll have to go back to 4s.

[@ChainsawFPV]

Alright! I'm gonna learn something today!

[@IVAN_ENT]

Have like 50 lishen 21700 cells left from building my ebike pack ,definitely gonna build a few packs

[@dg9bfc]

So. For long range use 18650 or 21700 cells.. And keep it low on the throttle (no punching if not needed).. They are not build for the current..

[@ArshaansEdits]

Basically the Li-ion cell has a lower C rating than that of the Lipo, That's why there was voltage drop.

[@redreefbud]

2.2v is low cut off for liion (good cell) molicel p42a 😁 but like 20a per cell output. So need more in parallel to match motor and esc.

[@redreefbud]

I build electric skateboards and scooters 😉 just getting into drones. Have a dji mini 3 pro but saw those supernova motors and had to have a set. So ordered the 2207 1980kv and going for a speedybee master 5 v2 and f7 stack 😁 i think the equal liion would be heavier but last longer in life. Each has their place 😁 beautiful place and keep the great videos coming

[@grimmliberty7447]

AWESOME AWARD granted! Best explanation of the difference I have ever seen. Thanks!

[@jdnic1]

I built an ultra light 5 inch that can pull 6amps when cruising And the voltage sag is almost non existent. When using lithium ion. This is because at %15 battery, the cells can still provide more than 5 amps. You can harness more out of a li-ion cell with a less piwer hungry quad. But you can double the c rating and amp output by putting it in parallel. 2s6p batteries is basically two 6s battery in parallel. So if you have 21700 baterry rated for 25a, at 2p setup you get 50a. At the cost of double the weight ofcourse.

[@benlay750]

The VTC6 cells in the pack are not high discharge 18650 li-ion. Try a true high discharge li-ion such as Molicel p28a slightly lower capacity but more than double the discharge current.

[@im_ricebowl]

"this area under the curve" I got ptsd for a moment. Im still taking my engineering course and I heard something way too familiar

[@dronepilot260rc]

I’m convinced that Bardwell never ages 🎉 been watching for years! Keep up the good work man 😎

[@flaparoundfpv8632]

Can't say the same for that wooden gate structure.

[@TheMightyWej]

I wonder if there is a way to increase the current carrying capabilities to compensate for the voltage drop, but I imagine this would involve the use of some beefy capacitors given the currents we are dealing with when throttling at full power, even if only for a brief time.

[@Fly_High_FPV]

UpgradeEnergy makes great Li-ions for long range, check out the Dark Lithium or the Botgrinder LongRange Batt

[@DKNguyen3.1415]

I assume the reason you say that you should pick a Li-ion pack in the same weight range as the LiPo pack is to to account for the lower discharge rating of the Li-Ion? As in: If you don't need extended flight times, don't attempt to reduce weight by going with a Li-ion pack half the weight of the Li-po in an attempt to reduce the weight but keep the same mAh.

[@KK-ol5ov]

I charged up my lithium pack for my GEPRC Croc 5 today and just wondered about this.

[@dividingbyzerofpv6748]

Used to be I could take a 6s2p 18650 pack out and get nearly 6-7 minutes of cruising flying out of a 7in or 10in build. 3.0v is the time to be close to home to land while 2.8 is for something wrong and you need another minute to land due to some unexpected nonsense.

[@DroneDocs]

For LiIon I land at 3.2-3.0v per cell. The last bit down to 2.8-2.5v is like emergency reserve fuel lol. On a GEPRC Mk5 with a 6S 4000mah I get 10+min landing around 3.1v

[@dividingbyzerofpv6748]

TLDW? Because useable voltage range you can use. But things get spicy on Lithium Ion when you fly below 3.2 volts. Basically better be looking to land, voltage sag is quick. 2.8v dips are right there. Parallel is needed for giving useable current. Higher series like 6s is needed to raise voltage so it helps to lower the current to a reasonable range handled by the parallel cells. Was building 6s2p on in and 10in builds 4+ years ago. Ran 6s4p on 13in Xclass. Planned next up was 8s4p for a 13in that could reasonably rip as well as something much bigger that would have been 6s8p.

[@EttoreEsposito]

So, if I've understood the mechanism correctly, if I want to enjoy a cruise ride with at most a dive or a little more, without engaging in freestyle maneuvers, I could easily opt for a Lion battery instead of a LiPo even on a 2/3"? Could I also do this on a TinyWhoop for more relaxed cruising to enjoy the scenery? It really depends on what you aim to do with it (sometimes I just love cruising around to take in the views).

[@lameandboard]

Ive noticed once you drop below 3volts it starts dropping a lot faster. I try to land around 3v per cell or just below it on lion

[@GiantAntCowboy]

Yea agreed. I’ve found that once it’s at 3v per cell you’ve used 90% of the pack & from there it’s drops very quick.

[@DFEUERMAN]

I agree dude, having made about four packs of 6S. I lost a quad listening to Bardwell 2.5v suggestion. (much love to Bardwell and his awesome work) The quad I lost went from 2.65v to zero in seconds. I think 3v to 2.9v is a safer landing threshold. I start coming home at about 3.35v, maybe sooner, depending on how far I've gone.

[@GiantAntCowboy]

@@DFEUERMAN yea, I always try to land before 3v, I save 3-2.5v for emergencies only. (Though I have drained them right down below 2v in one of my tests. Haha!)

[@DFEUERMAN]

@@GiantAntCowboy Haha, you're lucky the FC voltage regulator was able to handle the low battery voltage. (or did the FC power off?) My quad FC shut off over a cove of water. But the quad was so beat up, I don't miss it much. ✌️🪦 I think the 2.5v max discharge spec that JB keeps mentioning is intended for very light and slow loads like an LED flashlight, not for quadcopters.

[@GiantAntCowboy]

@@DFEUERMAN Yea, watch the end of this test video, kzbin.info/www/bejne/nam2l3dsha1khpI I pushed it as far as it would go… was an awesome test. 🏔️The quad actually survived, but was retired after this test. I used the parts for another build. However what’s really crazy is that I still use this battery pack years later to power my goggles! Molicel P42a cells are amazing, I push them well beyond their limits often.

[@TheJohanJonker]

Also remember 18650 charge time might be 3x more than a Lipo battery

[@mxracingunlimitedltd7784]

Why no Current/Amp Draw on the OSD? Im curious to see how many Amps this thing is pushing out during those full throttle vertical runs with the fully charged battery. It really did get up there quick and sounded as powerful as Lipo just by ear and how fast it punched up.. Im sure when the Li-ion cells get even better they will have all the advantagesbut without all the slight disadvantages vs a LiPo Battery Pack right now. Also, how is the charging time on this pack? Can it be charged at 1C or maybe even higher?

[@rocketman221projects]

The 6000mAh Geprc pack has a maximum charge rate of 5A or 0.83C. Most of the 18650 and 21700 cells have a recommended charge rate of 1C or less. Some can go higher, but they will get very hot and should use a charger with over temperature cutoff.

[@Pyromancers]

Maybe some light weight super capacitors could give you the big punches on demand with the 18650s?

[@PiDsPagePrototypes]

This test seems to show more the difference in C rating between the packs. 'Most' Li-Ion cells won't have the C rating of LiPo, because the Li-Ion cells are not aimed at a specific markets demands, but at general market usage - the manufacturer doesn't know when the cell is rolling down the production line if it's going to end up in a Quad, an EV, a Laptop, a Power Bank or a Torch, so they make them to have good performance in most devices. The major difference between Li-Ion and LiPo, is the cells are laid flat and the heavy metal case discarded in LiPo's. (Yes, there's some packs that use a different material for the flexible plates the charge spread out on, and there's plenty that use exactly the same chemistry as the Li-Ion) So when the Li-Ion are pushed beyong thier discharge voltage, they're doing the exact same damage to the cells, the cells are just less likely to pop in flight as they're held in a metal shell that doesn't stretch or crack open until much higher loads then the LiPo's. This is also why Li-Pol's are much more violent once they do reach the pressure that forces open the metal shell. While this test is fun to watch, it really doesn't deal with the Why of each types creation and market targeted applications. LiPo's exist because Phone Manufacturers wanted lighter batteries that could fit in thinner devices. Quad pilots and maunfacturers recognised the advantage of the form factor for thier use, and have taken advantage of the massive consumer demand for cell phones and the resulting push to make better batteries with higher performance. Regardless of the brand on the packaging, there's only a limited number of Battery Cell Manufacturing Plants around the world, and all a 'Drone battery manufacturer' does is buy up cells according to performance specification, assemble a pack and send them to retailers. That difference, between a Market Targeted Product, and a Generalised Market Product, is what we see here in C-rating and Area Under The Graph. Where the Li-Ion really has an advantage for electric flight, is for Wings, where it's easier to keep the center of mass ahead of the center of pressure if the cells are heavier, and where the lower C rating isn't such an issue for anything less then EDF's and Pylon Racers - if you've got anything that says 'Park Fly' on the box, a Li-Ion will save you money and fly longer, just a little slower at the top end. @Joshua - How about a comparison between Li-Ion packs, and LiFePO4 packs? The 4WD, Camping, and Solar sectors are driving the uptake of LiFePO4, but the only details availble for C rating on those appears to be how fast they can be charged, and how much more deeply they can be discharged without damage. Some 18650 LiFePO4 batteries are out to 3600mAH per Cell.

[@pro_key_concept754]

This is really interesting how would these 2 batteries compare to a graphene battery in performance

[@maro0016]

Actually lion packs are typically more prone to “pop” under load/high amp voltage. I had this happen to me once…

[@kurtisfoley2314]

waiting for solid state ........ I think its going to change the game a bit

[@enjoyyourlife2518]

Thanks so much for all your help . Your a hard working very helpful knowledgeable decent caring son of a gun so 👍 Thanks .

[@JefeDog]

You could potentially make this battery yourself pretty easily, for closer to $80 (just for the cells). I assume that they take six pairs that are in parallel, then put each pair in series, connecting your balance lead to the positive of each pair. You could even use the Samsung 30Q cell and get it done for closer to $60.

[@DKNguyen3.1415]

I think lithium-ion is also not as picky about state of charge in storage. More usage cycles in that sense.

[@PhonesandDronesRepair]

I recently built a little 2s li-ion pack for a micro FPV wing of mine believing the increased capacity would give me better flight times over lipo. I was wrong. A friend of mine in California has a working theory that due to a few factors, such as IR, you're best off going with a Lipo battery for sub 30 minute flights, and li-ion for flights over 30 minutes. Plane: LDARC 450x, 1206 5000kv, 4024 prop, 110g dry I was first using 36g 850mah lipos and getting a max flight time of about 17-18 minutes. I then built a 1200mah li-ion pack, with 18350 cells weighing 50g, that flew for about 20-21 minutes. Finally I bought some 1100mah lipos that weigh in at 45g. I'm getting 24 minute flights with those. The problem with the Li-ion pack is that they convert too much energy to heat. And then when the pack gets low on voltage you end up with with a negative feedback loop. The voltage is low which means you have to increase the throttle, which then just sags the pack more.

[@JoshuaBardwell]

If you are hitting the LiOn pack hard enough that it's getting super hot, then I agree. The LiOn pack needs to be used at low enough current draw that it doesn't get too hot.

[@rehepeks]

The negative feedback loop was the issue. You were drawing so much current from the liion that the voltage sagged a lot and that made you draw even more current to keep the power up. Most likely you were past the current at which the batteries are happy and that just transformed a lot of battery juice into heat. If the the weight and capacity difference is so small then indeed there is not much point going with a liion. Maybe a lower kv motor with 3S liion could be useful if the weight is not too much.

[@JimBridgerHarney]

Seems like you could just choose a bigger capacitor if you need more punch out power.

[@k1ortia]

Planes and wings are were it's at for Li-ion period

[@FPV-FlyWithMe]

thanks for another amazing video, I never even thought about how betaflight measures the cell power... THANKS for this, because until now I only displayed the cell current... :-) question: it seems you never found great lion packs, at least I cant find them in the description ? Just searching atm so... any hints would be highly appreciated !

[@thefatmoop]

There are a lot of built in safety features (and weight) of the cylindrical cells

[@Perceivedshift]

I've been chasing drift cars this summer, and often I really don't need a lot of punch but it would be nice do double my battery capacity! Could some changes to the throttle curve help make up for the lack of punch? Just to reduce the lag a bit if I find myself in trouble so I don't smash into a car or asphalt.

[@RichardAFPV]

JB... your first two LiIon links go to the same place.

[@spartan3299]

Ok...just thinking here...what about a combination of a Lipo and a LI-ion pack in series vs. parallel or a combination of cell types in a single pack to complement their strength to the other's weaknesses? You heard it here first?

[@spartan3299]

Nope, It has been done, but maybe not in the high current draws we see. "I am running a 36S LiPo with 43S LiFePo4 for 18 months with no issues." as a power bank...yes. " " As long as you make sure the voltage ranges and charge/discharge rates are within the safe limits for both batteries, you are good. You will not get good balance (i.e. the discharges will be neither balanced per pack nor consistent across the discharge curve) but you will get significantly more energy?" Huh, I wonder if heavy duty balance leads connected to one another of the differing pack might help maintain cell balances.

[@DannyFPV04]

Great info man!! Li-ion seems like it could be good for fixed wing aircrafts. Throughs?

[@dronepilot260rc]

For sure, I get over an hr flight time with a 4s 5000 mah li-ion pack 21700 cells on a Nano Talon Evo

[@hweissi]

I got a 2P4S pack in my 2.4m wingspan plane and it works great

[@DannyFPV04]

@@dronepilot260rc where’d you buy one of these from?

[@rehepeks]

For low current draw ones yes. A plane that draws a lot of current - no. Same with quads. Great for long range cruising but crap for racing or freestyle.

[@DannyFPV04]

@@rehepeks awesome. Thank you for the reply!

[@wiredforstereo]

So, LIon is better for fixed wings? Lower power output for longer duration.

[@shaneintegra]

One is a 3500mah Lithium Polymer battery The other is a 6000mah Lithium ION battery. Two different chemistrys The 6000mah is claiming to use authentic Sony VTC6 18650`s cells

[@gbraadnl]

This kind of Li-ion packs would work well for rovers or rc crawlers. Less need for punch

[@gbraadnl]

Will experiment with 2S2P config of some NCR cells

[@riddimgxd]

Hey Joshua can you do a video on the logic fpv sim, it’s the realest one out

[@selfish1716]

I stopped using LiPo batteries. I fly long-range (from 5-inch to 10-inch quads) with current Li-ion batteries, such as those with 45 amps per cell, I no longer need LiPos.

[@ErikWerlin]

For someone like myself who's still new to FPV (about 6months now) I fly 5" and sticky for cinematic and filming purposes. Do you have a recommendation on which battery to use and how long it can last? I'm currently using 6s 2200mAh Lipos and I get about 12-15min but would love to use something that can go for as long as possible.

[@ArcheantusFPV]

@JoshuaBardwell It seems that some of the performance between LiPo and LiIon packs is due to the operating voltage conditions under load. 3.6v LiPo vs 2.9v LiIon That is roughly 0.7v difference or roughly a 24% difference! If you normally use a 1850 kV motor would using a 2300kV motor compensate for the performance feel for LiIon batteries? Please please take a look into this!

[@JoshuaBardwell]

You could go to higher kv if you wanted, and that would raise the RPM, but keep in mind that you will do the same thing with your fingers by raising the throttle. If the voltage goes down, the thrust and rpm required to fly the quad doesn't change. Basically, that lower voltage is just cutting off the top end, and making your throttle position higher.

[@rehepeks]

@@JoshuaBardwell Maybe its time to revisit the 8S quad with LiIon battery? Try VTC5A cells, a bit less capacity (2600mah per cell) but higher C rating.

[@carmofpv]

For those who watched this video and others, I really recommend the patreon, you will learn a lot, there are so many people who understand FPV drones there, in addition to being able to ask questions on the live stream and buy and sell products, I sold a lot there xD

[@M-H433]

Not needed thanks.

[@sweed7777]

Do you think a large capacitor could be added to the pack? To help with sudden high amp needs. Like, with punch out or recoveries.

[@cloudpandarism2627]

nope because that capacitor is able to draw massive amounts of current to recharge. i tested it. makes no difference. what would make a difference is, if you can electrically decouple the capacitor from the pack and have a small PCB onboard charger which limits the current going in the capacitor until its fully charged and same PCB will activate it ONLY on full throttle punches. but to make it useful you need to have a huge capacitor on your quad. bigger than the quad itself i think. interesting idea for sure though... 🤔👍

[@techstuff6829]

There was a guy that made a combo pack with both LiPo for punch and Li-Ion for capacity.

[@rehepeks]

@@techstuff6829 Sounds like a good idea initially but in reality its not so great. Li-Ion cells should be used to a lower voltage to get the full capacity. If in parallel with a lipo then the lowest safe voltage of the lipo becomes limiting. So then you might aswell go with a higher capacity lipo.

[@FabioPaulinhoView]

I just build li-on battery for long range on samsung 21700 50S cells, they are better than 18650 vtc6 imo, higher energy density and cheaper, at only 5A less discharge rating

[@dividingbyzerofpv6748]

VTC5D was where I went for better discharge rates. Tried single 4200-4800 range high discharge 21700s long ago and didnt like them, sagged way sooner than the 6s2p 18650s that were 2000mah doubled for a 4k mah pack.

[@hateforall4012]

Id love a good long range recommendation form my Chimara pro v2... Im having trouble picking a battery. On top of that I get a few hundred yards across a soy bean field and the video starts cutting out.. DJI O3

[@truey90s]

That voltage sag is using 18650 cells. What if they were 21700 instead would that improve its performance??

[@JoshuaBardwell]

Definitely. Larger cells can provide more current.

[@ronmartin7253]

i accidentally overcharged a rc battery in 2011 and it literally flamed! and it was a hard fire to put out, and smelled horrible too. ....but, this killing-it by under volt, is there physical damage also? i have brought back old phone batteries from under volt using a pulse voltage so their charger will then recognise them again...

[@renePHTR]

i am building up a 7" long range, i have 2806.5 motors which could draw max. 50A/pc, having a 60A ESC. Question: i found a bat pack 3000mAh LiIon with 10C...could it be a problem? i mean: 10C equals only 30A..even with only using 50% of motor power it would rise up to a consumption of 88A..would be happy for some ideas or info....thx

[@madladdan]

JB really loving his goggles 2

[@stst8301]

I think that the v2 are better...

[@jonahbranch5625]

I'm wondering about how sodium ion batteries would work on a drone

[@BigE2343]

need that avatar hd goggles x video!!!

[@nuddin99]

I find it so weird that there is no goggles X review out yet. He hasn't even mentioned it anywhere.

[@BigE2343]

@@nuddin99 it is very strange

[@fp-AvERY]

Omg you are alive! 😂

[@musicvr3368]

Well, he said he will be on a road trip and would not upload for some time. No surprise.

[@fp-AvERY]

Listen someone has to give the man trouble. I know I was just joking around@@musicvr3368

[@proxemiafpv5746]

Nice video jb. What are the standard voltages for lithium ion batteries? Same as lipo? Minus discharge? For instance.. Full voltage: 4.2 and storage: 3.8? And can run them down let’s say 3.0? If you run it like that is this likely to generate reliability or is this considered abusing it?

[@BASSstarlet]

Why aren't there esc's that also take measurements from the balance lead?

[@rafaelm3404]

What about those GNB 70C lihv? A 4500mah is 497g. A 7000mah is 708g. Almost as lightweight as a Li Ion. Are they any good?

[@fpvlegenda]

im so sorry maybe its a lil annoying but i using lion bats a lot and i have some kind of problems statick Ampers at taking of way to high in my opinion its like 15-20 A at take off moment? and once at my 10 inch it went up to 60(with 5 kg additional weight ) but still kinda ???

[@ravenm1165]

what about a 3500mah lithuim, would it be half the weight, how would it fly?

[@josiahmos5880]

Can one have both in parallel on the same drone to get a middle ground? I.e. Lipo helps with power spikes and li-ion for longer flight time... A small lipo kinda working as a large capacity capacitor?

[@rehepeks]

You could but the low voltage cutoff of a lipo and liion are too far apart. With my liions I usually plan to land at 3.0V per cell, sometimes I end up a bit lower. With lipos I try to land at 3.5 or above to keep them happy. That would be a lot of unused capacity of liion side of your combobattery. Better to just go with a bigger lipo.

[@MCsCreations]

Awesome flying and review, Joshua! 😃 Thanks for all the info! Stay safe there with your family! 🖖😊

[@isavv_]

My question is... Does the voltage under load count as minimum voltage? (If you punch out a lipo and falls under 3v/cell, will you damage the battery?)

[@QuickNick2402]

As I understand it, you will damage your Lipo if it falls under ~3V period. So yes, under 3V during a punch out will damage it. At least that's what I've always heard and how I fly my packs

[@lameandboard]

3v is very low for a LIPO. I stop at 3.6 I think or 3.5v per cell average

[@gpaull2]

The rebound voltage after sitting is the important number.

[@isavv_]

@@QuickNick2402 Makes sense! because you are under 3v no matter what.. but there is a debate that the recovery voltage is the most important, that's why I asked.

[@markfpv22]

Congrats for 300K