GEPRC Crocodile 7 long duration, long range fpv quad // 6s 18650 li-ion battery testing
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- Опубликовано: 21 авг 2024
- In a previous video I showed how to build 6S Lithium Ion battery packs from NCR18650B cells for long range fpv and long duration quads. Now's the time to put the packs to the test and see just how they perform on a GEPRC Crocodile 7 FPV quad.
Each pack weights 319g
Here's the results:
On a single pack • GEPRC Crocodile 7 long...
Lithium Ion capacity: 3400 mAh
Flight Time: 20 minutes
Final pack voltage: 19.5V
Final cell voltage: 3.2V
All up weight: 795g
On a double pack • GEPRC Crocodile 7 long...
Lithium Ion capacity: 6800 mAh
Flight Time: 34 minutes
Final pack voltage: 19.5V
Final cell voltage: 3.25V
All up weight: 995g
Check how quiet it is: • GEPRC Crocodile 7 long...
These are impressive flight times, but remember they are only lab conditions, flying around the garden at 1m. But it's a good indicator of what they are capable of. In the next video I'll get out and try some proper flights with a bit of gentle acro, but at least I know what the bench limits are. I will be carefully calibrating my OSD voltage monitor and keeping a close eye on the flight time and battery volts in the goggles OSD.
Realistically I guess I'll get around 25 minutes useable flight time. I don't recommend lithium ion for acro or racing, but for long range or long duration they're a great choice.
GEPRC Crocodile 7: bit.ly/2ZgOQgq
How to build a 6S NCR18650B Lithium Ion pack: • Make your own 6s li-io...
Calibrating your Betaflight OSD voltage monitor: • Calibrating your BetaF...
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![☀ Дальнолет, которого все ждали. Мощь, тяга, скорость. [GepRC Moz7]](http://i.ytimg.com/vi/WZIQRYbxzpQ/mqdefault.jpg)
Previously having a Mavic and now getting into FPV and acro flying I’ve wondered why there isn’t a “Best of both worlds” solution. You pretty much answered that question and gave us a “best case scenario” example. Thank you for all of the time, hard work and effort you put into making these videos. Well done and very informative. Thanks again and keep up the good work.
Thanks for the feedback and for watching.
I like the organization of the components
Lots of space in there. Thanks for watching.
FYI You can wire smart audio directly to the crossfire receiver and control the vtx through your transmitter! Just need the crossfire Lua scripts!
I tend to fly long range on my own so I rarely need to change VTX channels, but thanks for the info. Always good to know.
Why crossfire? I use R9. Same feautures. OTO. Same Range. 1/3 of the price?
Ok ok ... estheticly TBS's looks better. But u know the mod world? R9 will not draw inspiration from a early 2000's cell phone ;)
@@mlit83 you can't use smart audio directly from an R9 receiver... Crossfire literally gets around the issue if you don't have enough uarts...
I've used both extensively, I got rid of R9 when fail-safes started to cost me a lot more money them I was saving by using R9 in the first place. Only time I've fail safed on crossfire was due to a broken antenna on the TX...
Wow 30 minutes that's great! I have been looking for a reasonably priced quad for long range flights. I'm slowly building my ground station but I really think I'm sold on the crocodile
Well, just found my idea for a summer build.... brilliant🤙
Have fun!
Brilliant video thankyou so much .....been looking for a video like this for weeks wow I have just found my dream quad... looking forward to you next presentation cheers 🍻 I know nothing about it I have 1 month experience with a air 2 .. great drone but.. this is what I have been looking for ....if you are free sometime I'd like to ask you a few questions ...
I love it!
Thank you for this movie! It is good to know that we can fly on 18650 too :)
Thanks for watching and the feedback.
Totally agree with Seli-Fpv down below, your video was a very nice change from the standard “Charlie Brown’s teachers” wah wah wah videos on RUclips lol. Great job imparting the info and keeping it interesting. 👌
Thanks for the feedback. I've got my style and I'll stick to it.
Thanks for this review, actually made sense with no racing, decent duration and potential for high quality video. I will be interested to see the GoPro footage once you can get out and test it.
Glad it was helpful!
Interesting video, thanks for posting. I’ve had similar results with my 7” Vortex 285 but via a different route, large 3s LiPo packs, 7” 2 blade props, 2405 1850 motors. The 3s packs give similar flat discharge characteristics to Lion packs with a very predictable last couple of minutes of flight. A typical flight time is 20mins on 5000mAh covering 5-10 miles.
Thanks for the info!
The battery life is literally the only thing preventing me jumping in head first and buying all the gear. I keep reading 5mins flight time. I refuse to spend £100’s and driving to scenic places for 5mins or constantly changing batteries.I just want to be able to fly for as long as possible in FPV around pretty places.
Nice to see what you made them bats for now. Great project, I got out again yesterday on a epic flight not uploaded it yet not edited. A like from me 👍🏽😊
Thanks for watching.
It was nice. Thanks again. I'm changeing from my 5" to 7" LR. We will see how it goes. I need to check how you created those packs :)
Here's my pack build video ruclips.net/video/u8EkRS_c3MM/видео.html Thanks for watching.
I really enjoy yr channel, I am doing some range testing on the Express LRS RC link and was looking to build lion packs for extra mileage, can't wait to see some great cinematic footage, happy landings
Here's some. ruclips.net/video/TT-jyG1JV98/видео.html Shame about the rain drops on the lens though. Thanks for watching.
Good stuff! Never been interested in long range but this differently getting me closer. Side note, when I started I seen a video you made and copied your arming switch locations and have keep it the same way ever since. Hoping you guys get out soon!
Best thing to do so the muscle memory knows where the switch is. Thanks for watching.
Hey just wanted to say I found your channel and I love it , your a great teacher on this stuff, keep doing what you do brother 👍🏻
Thanks for the feedback.
Thanks I really hope you pursue this after the lockdown would love to see the full flight results.👍
That's the plan!
1st visit. Thanks. That's been the most education I've received in some time
Glad it was useful.
I have been wanting to build a long range FPV. Thanks for sharing your experience and insight. Very helpful.
Glad to help
WhirlyBloke FTW!!!! Baby!!!
You deserve more subscribers than 6k! Great video! Thank you :)
Wow, thank you!
Hi you can use crossfire and GPS and retain smart audio in the stack...got it working on mine. Followed drone camps video on it. Great work on the custom pack! Inspired me to dust my croc off and get flying!
Very true. Thanks.
@@WhirlyBloke yeah just checked use sbus and T3 for crossfire....it was a head scratcher setting up as I came to the same conclusion as you - that you had to sacrifice something else to get telemetry. But it works aok
Can you please share the link on that? Thanks!
Haha neighbor didnt complain? Good lord 23mins? Thats too much time haha.. Good video WB!!
I waited until they went out.
Wow! I'm glad I bumped into your channel! If I could like and subscribe twice I would haha. What an enjoyable video! So refreshing! Perfectly explained valuable information, entertaining, well edited, well shot... You're really good at this! Thank you for sharing your ideas.
Thanks for the awesome feedback. It's good to know the hard work is appreciated.
Amazing quality video and really interesting content. Thank you so much for taking the time and sharing!!
Thanks.
Thats a super idea with the liion bats. Thanks 👍
Thanks for watching and the feedback.
I Got 10min flighttime Output of my 5" hex it Uses a 3s 2400mah lipo and emax mt2204 3200Kv Motors, and Simonk 12A Esc. For acro i use a 4s lipo and get around 5min flighttime.(Naze32 as a flightcontroller, running cleanflight)
I know its is a very old tech build But i had the Parts from my 1st quad, and I buyed a 2nd Set of Motors and Esc back than becourse i Broke 1 Motor and Esc in a Crash. Also this was the cheapest Option for me.
Nice work.
youre oldschool man, nice
Looking to improve my long range setup. This was very informative. Thx
Glad it was helpful!
Oh nice I am from St.Ives cool to see it in some fpv!
Very cool!
@@WhirlyBloke Just an update I got off sim about 2 months ago and went to a GEPRC Thinking P16 and took my first flights. I am about to move up to a Crocodile baby now. Really like the GEP models so far and that cruising style.
Amazing flight time 😲
I know. Not fast and furious. Just smooth and relaxing. Thanks for watching.
Pro-tip; get some high current 18350's, stack 2 on top of each other (with something insulating inbetween) and wire as parallel.
Bam, an extremely high current Lithium-Ion 18700 cell, just a tad longer than an 18650.
Repeat for however many you need.
That's true, but a better option I'm working with now is Molicel P42A 21700. Gives you 30A @ 4.2Ah.
@@WhirlyBloke Amazing! I'm just curious about how much amp's it can handle without deterriorating the quality of the cell rapidly.
Great insights. Immediate subscribe! Don’t know how I hadn’t seen your channel before.... Thank you for sharing
Welcome aboard!
Not sure about betaflight but you need to do 2 things to get the full range out of the batteries. First go in and set the low voltage in the ESC setting down. Either turn it off of down as low as it goes. The esc's have a low voltage cut off on them and will either cut power to the motors or reduce power to them which it sounds like its doing. The other thing is if it allows it in betaflight set a battery profile up for your liion packs. Reduce the cell minimum to 2.8 - 2.9 volts.
All good info. Thanks.
I have a 2" cine pro 4k from GEPRC and it's been my go to, absolute blast, even more fun than my race CMW 5". Your video just convinced me to order one today. Thanks!
The Crocodile is very good. Thanks for watching.
hi there ive just found your channel its right up my street i fly fpv freestyle and also got bigger kwads for long range my biggist is 9 inch frame im going to try the 18650 batterys o have thiught abiut lion packs before i also loke your channel as your about my age im also from the uk anyway ivesubed to your channel so thanks so much im looking forward to binge watching you on the weekends when its bad wether and thats all the time as winters on the way lol have a great day
Hi and thanks for watching.
You can build a 5” that gets 9.5 minutes with the (Stan FPV 2604 1690kv) on 1500mah 4s pack. I’m using 5040x3 props. For just cruising got about 35 or 40 mph, I get 9.5min and land when the pack is 3.7 per cell. I have 6cell packs coming. I hope to increase that time.
6 cell li-ion are more effective.
@@WhirlyBloke I’m going to order one now. Thank you
Right after I have my tea and biscuits
Indeedy
thats why i love F7s
Me too.
You can connect your vtx smart audio direct to your crossfire and control the channels via the crossfire lua or if you have the full size tx you can control the channels in there
Awesome test
Thanks for watching.
Build 6S in long side to fit perfectly on top/bottom chassis. Better aerodynamics.
I had my fly 45minutes flight time on low KV 1700 motors.
Doubling the battery pack will give you 50% more flight time if 1st pack is in 1 to 4 power ratio.
Good point. Thanks for the feedback.
Power will drain faster during hovering as compared to cruising or flying with tailwind so most probably you will get even longer flight times in cruising
I'm getting about 40 minutes flying time.
@@WhirlyBloke wow 40mins while cruising?💪
@@chuansheng yep
You could 21700 for even more time/power vs the 18650, would love to see it
Why not have a go?
Спасибо. Очень интересно. Удачи тебе.
New sub! Great job mate! I might use in next build!
Thanks for watching.
@@WhirlyBloke love hobby...making video Wednesday..think you'll like. 👊👊💪💪
impressive!
Thanks
Very interesting video. Thank you.
Glad you enjoyed it
Bit of a late comment, but if its possible to use external vtx you could stick in a unify pro HV and wire us as crsf to rx.
Then you have full vtx control via agent lite.
The bare cells are 47.5g each. So those 6S packs must be over 300g each. How are you getting 200g per pack? Maybe the 995g AUW weight with the parallel packs is actually your 1kg scale maxing out.
319g each. Check my other replies for details.
Whirly Bloke Got it. Thanks. Couldn’t go through the hundreds of comments. Was just going by your video. Wonder if you can add a graphic to the video or some text in the description about the battery weight.
Super vid. My frame just arrived and i'm starting my build. Did you ever get around to making the follow up flight tests?
Thank you 😊
Thanks for watching.
esc are set to cut of min voltage try that. volt = rpm but you have a low throttle hover so will still fly
Thanks for the info. And thanks for watching.
excellent explanation.... really !!!
Glad you liked it!
you can use te xfire rx nano for vtx te 4 hole down the side can be used in that way
Good info - thanks.
🇺🇸 Thank you Mate, very nice video, i am thinking of getting this drone but a bit gun shy with BangGood due to poor customer service from a previous RC purchase. 👍I did subscribed to you're channel! Safe flying God Speed! 🐾🐾🐾☠
I know others have had problems with Banggood and I can't really comment, but I've been using them for 4 years and hardly any issues. Any problems have been sorted out, but don't expect things to turn up next day. Go with whatever you feel comfortable with.
Try the Samsung 21700 35c 4000mah in a 6s configuration. You will be amazed with the power and flight times.
They are very good. Bit more expensive though.
That’s very cool but I’m wondering what the time would be like at a 50 mph cruise, I’ll keep watching when you do a cruise
ruclips.net/video/TT-jyG1JV98/видео.html
rescue quads cost like 100k usd. if you can get around 30 minutes cruising, with infrared camera, this drone can be used for search and rescue, and make a whole bunch of them for 100k usd.
Now there's an idea.
I just bought my x9d plus se, next i be getting the goggles next i want to get this. Thank you for the info.
Glad it helped. Thanks for watching.
Do not forget to buy an upgrade for your radio mate. I'm on pretty cheap gear myself, but after a few mods, turns out they're all the same. QX7, 9XD.
Anyway,many lower cost goggles are 9/10 in terms of quality. Second hand FatSharks with discounts up to 50-60%.
I import 80-ish % of all component from Korea and China for half the price US customers pay.
Most importand thing you do, you get the ABSOLUTE LAST VERSION HARDWARE OF THE FrSky R9 ISM Band RC-link. Gives you superiour range. Same as TBS. TBS introduced me to quads. The Discovery Pro. I ordered a fuckload of parts, paid, but never recieved either project nor a refund...
@@mlit83 thanks for the heads up, but what you mean by upgrade my radio? When i bought it , they said it was the latest radio. Sorry you had to go through that with the parts and your refund , hope everything works out, but thank you for your help.
You should build the packs from some better 18650s. Those NCRs are rated at 6.7A. If you get some at 20-30A, you should get better performance at lower voltage.
As I pointed out these were some 18650's that were lying about doing nothing - they aren't the best for sure, but they were free and proved a point. Check out my Crocodile Baby 4 review for the 4S Li-ion pack I built from Sony/Murata VTC6 cells.
Nice job. I’m looking at getting into the FPV world and the crocodile is the one I’m looking at so I appreciate this bit of knowledge. Do you have pointers or recommendations?
Thanks for the feedback. Check out my other video about the Croc 7 ruclips.net/video/oLJhuiPJDAM/видео.html
excellent! ive been bouncing around trying this on my hexacopter but im afraid it is pulling way too many amps. i really like your setup
Glad I could help!
Using samsun INR 26C gives it a bit more OOMP with a little less capacity.
Very nice video. I'm really tempted to get something for long range for next season.
I'm wondering, what is the weight of one of those 6s li-ion packs? I've some 6s lipo packs that I use in my RC truggy and I wonder if they'd be good to use for a drone like this or will the weight be too much.
Cheers!
They are 319grams.
Great video, thanks. The max continuous discharge current of the NCR18650B is 10 Amps. Did you measure the current of the 7" geprc during hover? I assume in normal flight current is higher than 10A and will damage the cells.
This isn't driving the pack hard and they will only delivery what they can. I've been flying these packs for months with zero issues. However, using Sony VTC6 or equivalent cells works better.
A guide on configuring pid and filters would be useful ....
Noted!
Im a simple man, i see 18650 battery pack, i sub scribe and watch :P
Thanks for watching.
Thanks for the great video. I see .in your description that adding a second pack only increases the weight by 200g but each NCR18650B cell weighs about 45g, if there was an addition of 6 cells wouldn't the increase be slightly higher? If not which type of cells did you use since the ones on your 6s li-ion long range drone battery pack are 46g each. By any chance is my math wrong?
Your maths is correct, it was a slip of my tongue.
Hm, really nice video. I am interested in long range / long flight time cinematic drone and was considering the LAL 5 with 7" replacement arms...... Any thoughts on that idea?
Sorry I haven't got any experience of that one.
😃 amazing
Thanks 😄
really impressed ,i f you was to do a punch out, the current draw of most 7inch builds, would exceed what the cells are rated for in 6s1p configuration?
Thanks. True, but remember the batteries will only deliver what they can regardless of how much current the motors demand. And they are only really suitable for cruising. I've moved over to 21700 cells and they work even better. Thanks for your feedback.
This is amazing. How does long range stuff work in the UK? I live in the middle of nowhere and want to try long range. Can you literally just fly out as far as you want as long as it's over fields etc?
In theory, no. 500m is the legal max.
@@WhirlyBloke ah ok, same as 25mw is the legal limit. Got you 😉
Thank you for sharing. How long the RJX battery trap that you use ?
How your 6S pack can be only 200gr when the average weight of any 18650 Li-Ion is around 50gr ?
My 6S Sony Murata pack weight is 306gr !
Trouble with my worms. It's actually 319g
If you discharge Li ion battery’s close to the maximum Current you wont get the full capacity out of them. So if you fly with osd you probably only can use around 3000mah before you need to land.
Thanks for the feedback.
Hi bro, I have a doubt hope u can clear me...
In the Li-ion cell u used, the peak discharge current is 10A. As I searched about the motor u used with the 3 blade props, each Motor should consume about 30 to 40A.
If for 4, it must be of 120A to 160A even in the crusing speed.
How this much of current the battery could discharge?
How can I understand this happens!
If the pack was in series, however the voltage multiplies with constant amperage.
Have you considered soldering a 7s Li-Ion Pack? That way you should get closer to the 2,5v end voltage without too much added weight
Worth thinking about.
I have been trying to decide between the Gep RC croc 7 or the Flywoo Mr croc 7 inch HD. The HD system is just too alluring to miss out on though so I shall save my cash for that
DJI digital FPV is very good indeed.
I think im gonna give this a go as well...15mins is already looooong for fpv flying...
It's awesome. Thanks for watching.
Li-ion cells are different chemistry as well. So there is usually tradeoff between internal resistance and capacity:
- Panasonic NCR18650B 3400mAh IR 55mOhm
- Sony vtc6 18650 3100mAh IR 13mOhm
- Sony vtc5a 18650 2500mAh IR 9.8mOhm
So for long range FPV VTC6 are more common.
What's the cruising speed of your drone BTW?
Really useful info - thanks. I've got another long duration project, so I'll give the Sony VTC6 a try. A good balance of capacity vs internal resistance.
34 minutes is really nice, but 3400mAh seems pretty low for 6x18650, I've got on my desk Sanyo/Panasonic NCR18650GA 3.6V - 3.7V 3500mAh batteries, so 6x(that) would be 21000mAh of capacity. Am I missing something or are you just using low capacity cells?
You're misunderstanding how to calculate current and voltage when cells are in series and parallel.
@@WhirlyBloke I guess your battery pack is series, so when calculating the mAh, you take the capacity of one cell? But in parallel, then you add them together?
Lol I'm building a 7" quad myself. Not being Fast and Furious that got my attention, haha
Enjoy it. Thanks for watching.
Great info. I am learning to fly acro with 3" quad & struggling so I think this would be a better option, What do you think ?
It stick with the 3 inch and keep practising. You'll get there. The Crocodile is a big quad and can cause quite a lot of damage when you crash.
34 minutes.. Awesome.. my video
Think 6S Lithium Ion = 4S LiHv or 5s Lipo.
my guess it you need to tune for @16v.
15v just enough to hover last few feet home at full throttle.
The tune only needed a few tweak TBH.
Such great information fair play, any idea where a guy could get a lithium ion battery?
bit.ly/2TDyZVH
Excellent Video ZOHD LionPack 3000 mah for my geprc crocodile baby ....... I used to fly with 4s Lipo.... Do I have to make any change on my setup on (Betaflight or in the DJI fpv goggles) to get the Lion battery voltage reading ? I flue 1 time with the Lion pack and I get the low battery warning 5 minutes after take off.
Thank you.
Maybe change the low battery voltage warning levels.
very good video bigger props like a truck gets 10 miles a gallon if carrying bread or bricks. bet can carry even bigger gas tank??
Probably.
Gonna follow this close in order to probably emulate. Any special reason for keeping of the batteries ontop and not below making even larger props possible?
I just like top mounted batteries. Thanks for watching.
@@WhirlyBloke We got the same "250g" rules in Sweden and anything above it needs to be registered so in order to go through that i am trying to find something that can hover a long time. The frame you are using is a 315mm weighing in on 174gram? Looking at the frame and are those arms foldable?
@@petfrogg No the arms aren't foldable.
Great video. What would be the price of this drones without the gopro? Subbed
Church turf links in the description for prices. Thanks for watching.
I watched this because I'm about to try running a pair of 2200mah S2's on a Darwinfpv T129...260gram total batt weight... I'm only doing it because I'm not using the batteries for anything else...🤷🏻♂️
I put on 8" blades on and ran 12,000mah
This setup is likely to result in a heavier drone with a longer flight time compared to a typical racing drone setup with 5-inch propellers and a smaller battery.
While the 8-inch propellers can generate more thrust and lift, they can also require a higher voltage and may put more stress on the motors and ESCs (Electronic Speed Controllers) compared to smaller propellers. It's important to make sure your motors and ESCs are rated for the higher voltage and current draw that the larger propellers will require. Running the motors or ESCs beyond their rated capacity can result in overheating or even failure.
Using a larger battery like the 12,000mAh one will provide longer flight times, but it also means more weight that the motors and ESCs will need to lift. It's important to make sure your drone's power system is able to handle the additional weight and current draw from the larger battery.
Overall, it's important to carefully consider the compatibility and limits of your drone's components before making any modifications or upgrades. Improperly matched components or pushing them beyond their limits can result in damage to your drone or even create a safety hazard.
Have you seen recently Dave_C 18650 modular battery clip approach ?
Would you lose much efficiency using them instead of welded packs?
You'll lose a bit in a connector rather than a soldered joint, but it's marginal.
My first drone was a long range hex which had a 5 minute flight time. I crashed and broke the arms so converted it to a qua which got me 12 minutes + Landing flight time @3.79v per cell on a lipo.
I'm looking at building a 5" but 7 sounds better as my first is a 10".
I'm using the Naza M V2 FC which is a great FC for beginners. R9 receiver and R9M module for the long range. I just need a long range VTX to be powered from my 4S 6200mah lipo. I'm thinking of either putting my runcam ontop of my GoPro+Gimble for smooth flight viewing. Do you think that would be a good idea or should i keep the Runcam on the frame?
Why not change the FC and use iNav for that DJI experience but with acro?
9:02 It sounds like Mavic Air 2!!
Sort of.
Awesome! Did you build the pack or buy it..if so can you link me to where I can get one.
Thanks. Here's my video that shows how you can make them. ruclips.net/video/u8EkRS_c3MM/видео.html Thanks for watching
New to fpv and ..so new I only have a controller so far .. playing around with a sim and slowly researching and deciding what to buy . Anyways this is super interesting to me as someone coming from mavic type drones . Once I have more experience I'd love to try this out . I have the tbs module with my controller ..is that good for these long range type 7 inch quads ? Is that what they use to get so far ?
Welcome aboard!
Thanks .. everything is really overwhelming. Im struggling with goggles atm. Deciding between if i want to go digital or analog is really racking my brain.
would be good to see a 3s2p 11.1v setup
Maybe....
Hey there,
Any updates on these batteries? Have you been able to get out and really test these? I built a 6s 4000 mah 21700 version to use with my Flywoo Mr Croc and I'm able to easily get 15mins but I've never really pushed it yet. Just curious how yours are doing.
Should I use these batteries for a 6s2p pack for 7" drone ? I calculated the weight = 840g. Where the 18650 @6s2p = 528g.
That's 312g more if I use the 21700. Which one you think I should use ?
When deciding between using 18650 or 21700 batteries for your 6s2p pack for a 7" drone, there are several factors to consider:
1. **Capacity**: 21700 batteries generally have higher capacity than 18650 batteries, which means they can hold more energy. This can translate to longer flight times for your drone.
2. **Weight**: As you've already calculated, the 18650 batteries will be lighter than the 21700 batteries for the same configuration. Lighter batteries can result in better agility and responsiveness for your drone, potentially improving its flight performance.
3. **Discharge Rate**: Check the discharge rate (C-rating) of both types of batteries. Drones often require high discharge rates to deliver enough power during aggressive manoeuvres. Ensure that the selected batteries can handle the drone's power demands without significant voltage sag.
4. **Availability**: Consider the availability of these battery types. It's crucial to choose batteries that are readily available, as it will be easier to replace or expand your battery packs in the future.
5. **Cost**: Compare the cost of both battery types. Typically, higher-capacity batteries like 21700 tend to be more expensive than 18650 batteries.
Given the information provided, the 18650 batteries seem to be the more lightweight option, which can positively impact the drone's performance. However, you'll need to weigh this against the potential benefits of longer flight times offered by the higher-capacity 21700 batteries.
Ultimately, the decision comes down to your specific requirements and preferences. If you prioritise flight performance and reduced weight, go for the 18650 batteries. On the other hand, if longer flight times are more crucial and you don't mind the additional weight, the 21700 batteries might be a better fit.
@WhirlyBloke Man that's an intense and full answer thank you so much. So what I also understood by your answer that a 7" quad would lift that 840g pack but that would affect the performance and a more load on the motors which lead to more current draw.
Brand new to quads here. You say, one must take care of lipo batteries or they puff up. My first battery is already getting slightly puffy and I didn't even know it was a thing until just now. What do I need to do to extend the life of my batteries as long as possible?
Don't over charge them, don't charge at anything over 2C (I always do 1C), don't over discharge them, don't fly them below 3.5v per cell - it kills them, store at room temperature at storage voltage. Flying hard on very hot days will make them puff up so watch out. If it puffs up badly after a flight, put it in the shade to one side away from anything flammable - just in case. You need to look after your batteries cos you will invest more in them than the quad over a year.
@@WhirlyBloke Thank you! i have the TinyHawk RTF, it came with it's own 6 battery charger, I've been charging 2 or 4 batteries at a time, using a standard USB - it takes about 20 mins per battery to get them to about 80% - is this a good way to do it, should I adjust anything? I only fly in stability mode from LOS right now, because I'm still not very good, I assume that's a relatively low rate of discharge? I'll try not to use them on hot days and not to run them totally dead anymore.
Hi. By long range, what’s the distance you are talking about?
It is something I’m contemplating to get onto next. Appreciate if you can share your experience. What's the VTX you use for long range? Thanks.
I haven't had a chance to check distance yet. I will after the lockdown is over. But at least I know the flight times. Thanks for watching.
@@WhirlyBloke really looking forward. Do you use a ground station for receiving the video signal?
Hi. Are you guys out of the lockdown yet? Managed to fly this on long range yet?