Finally a decent video on building battery packs, but one thing I do differently is to make sure that the balance leads are the same length. Keep up the good work and God bless you and America 🇺🇸
Today I made my first 4s 21700 ion pack. Some tips for beginners to avoid mistakes: always double check every connection you make, read and understand the wiring diagram of your pack first! Good luck! Spot welder recommended.
I've been building 3S Li-ion packs out of Sony VTC6 cells, they work very well with the Explorer. Yes, you have a slight performance loss due to it being a 3S pack, but flight time remains the same. I buy them for $5.99 a piece.
I just received the 21700 4s from Fpvcycle and I flew my Shendrones squirt 2203 3450kv for 13min with a gopro and the voltage at landing was around 3.2 per cell. I was freaking shocked.
Just saw this video. Bought some molicels myself last week. Bought fish paper along with and a mid range low end spot welder. That kweld was just too expensive. Went with .20 8mm pure nickel strips. Hope mine turn out well too! I have all the balance leads and wire I think I will need. I am looking to build 3s and 4s cells. I went with 85mm pvc heat shrink for 3s and 120mm for 4s. Guess we shall see how that works out
Figuring out the right size heat shrink was the hardest part for me. Needless to day I have a lot of extra heat shrink laying around now! I agree on the kweld. The only reason I have one is someone was selling the kit unassembled for a crasy low price and I was able to swoop in and scoop it up!
30Q and VTC 6 have Petty much the same discharge. The 30Qs 15A are continuous and the vtc 6s 30A are burst only. Realistically they both can deliver 20A continuous on drones. The best cell however is the P42A since they have even better power to weight than all the 18650.
VT6 said continuous online 30a.. they just recommend temperature protection if using at that amount.. doubt any of us using 30a continously.. I'm at like 10a lol 30Q is 15a continuously I do want to try build a P42 pack. That be nice. 50% heavier but worth it.. than going 6s2p or 4s2p
@@TweetFPV yes 21700 cells scale a little bit better compared to 18650. For lighter drones you should go down to 2s or 3s with them but for bigger ones 6s1p or 4s2p is great.
Thanks for this. I’m trying to build a 4s 18650 Li-ion battery pack for a PAPR fan unit. The real deal costs $1000 which is why I’m going DIY. Your video is very helpful
This reminds me of the days when i used to make my own 6 cell NiMh packs for my rc cars, only that this is a bit more dangerous with the lithium cells.
Very nice show, thank you. Currently, I'm also getting a background on properly building packs myself, as it's not readily available in my area and ordering is a headache with land\sea delivery more than a month waiting times.. My concern is nickel strip you've used - matching standard is SSPN-0013 if that's pure nickel (0.2x8mm). Now this strip have max 9-12Amps rating for a single layer. If you want like 30th Amps currents you'll need at least 3 layers, which is still fine and acceptable, just need to weld 3 strips for each bridge on top of each other... But my concern is overheating - we all know how much current 4S quad could theoretically draw on freestyle active flying. For example, testing single 0.1 by 4mm strip with 15A current it'll heat up to +55C, at 30A it's about +500C (Nickel melting point is 1455C or 2651F and for 0.2by8mm strip it will be a bit different) as for the batteries - they normally take up to +60C temp (charging, rapid discharging as per specs sheets) - obviously depending on the battery model. Second point - voltage sag for Li-Ion - for example top quality packs on MOLICEL P26A cells as you mentioned could theoretically provide up to 35A, but as per testing it will immediately sag to 3.43V during such current draw... which suxx... Any ideas on that?
Ideally stacking or using thicker strips would be ideal but the application we use li-ion packs for a typically low amp draw. That's why you only really see them used in either very high voltage applications (ohms law volts go up current goes down) or low amps applications.
@@TweetFPV Sir don't get me wrong! I'm not here just to argue or something! :) Just wanted to clarify for myself...I'm also now planning to switch to Li-Ion and wanna be on a safe side... regarding the current - if you have time\desire check CJ Davies - Flying my home-made 4S Li-Ion batteries // Samsung 30T 21700 Apr 24, 2021 in youtube - guy shows his full OSD stats at the end after old lady style first test flight on his 4S Li-Ion pack and the max current was 50Amps... again - no freestyle whatsoever... So, I wonder, if even 2 strips are enough in terms of safety... as he used single 0.2 by 0.8mm, which is rated for 9-12 Amps and that is STILL not enough
I would think there is a time/current/distance factor for the strips. But when in doubt stack em up. I honestly don't know. Might make a good video to pull my pack apart and the auline that I have to compare the construction.
@@TweetFPV That is actually very good idea, interesting what is behind their shrink warp... and you may do that in non destructive way either, I believe... I mean your method is more than adequate, at least for me being a noob in lipo\li-ion packs... actually... now that I've mentioned that... I've been using all possible Li-Ion packs for several years as a vaper :) and back then we've used as much amperage as possible from a cell due to very low resistance coils, so yeah! :) that's why this topic is interesting :)
I've dissected a few of these flight packs and big manufacturers do not use any sort of cell holders or spacers. At most a piece of cardboard or fish paper between the cells.
Great video! Any experience on the thickness of the welding-stripes? Only have a cheap welder which can only go to max 0.15mm. Will 0.15x7mm be enough to drive ~8-12 amps?
You can double up possibly. With this 4"lr you won't be pulling too many amps. You will probably be fine with. 15 strips but I would fly and then check the temp of the strips.
@@TweetFPV Will these Li-Ion cell work for my below hex? 1)Frame:Tarot 680 PRO Folding Hexacopter Frame 2)Motors:6x Tarot 4108 High Power Brushless Motor (380kv) 3)Propeller:3x Tarot 1355 Carbon Propellers (Two Holes / CW and CCW) 4)ESC (Electronic Speed Controls):6x Hobbywing XRotor 40A-OPTO ESC
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
Those cells are very heave and don't offer much discharge rate. They are probably too heavy for your cinewhoop. Li-ion packs are usually used on very efficient crafts with 4inch to 6inch bi-blades. Cinewhoop a are very ineffecient and require very high discharge packs that's why lipo packs are used. Try using a 850mah lipo from a reputable manufacturer.
@@TweetFPV 3-inch cinehoof, weighing 350g. The motor is 1408 3600KV. Is there absolutely no way with my drone? What if I reduce the weight or change the motor to a lower KV? If you change it, how many KV and how many grams is appropriate? I've bought too many 18650s... I'm desperate.
I probably meant to say fish paper but it's the thick cardboard type paper that separates the cells from rubbing on each other and then the other one is kapton tape I might have mixed the two up
No, when you make a series pack (which is what you are doing) you get the same amp rating but you increse the voltage. So you pack will only be 5a. When you wire in parallel you add to the capasity and discharge rating. But your voltage stays the same.
What pcb would you recommend for something like this? Need short protection with over charge and discharge protection. I’m wiring in a pack and need to protect the supply itself and the tools. Thanks!
@@czaro8006 the way this pack is built it isn't intended to be charged In a charger like that after its assembled. This configuration is intended to be charged In a rc hobby charger like this amzn.to/3HHLvwb
Hi bro I have a quadcopter f450 with 920kv motor and 30a esc 1045 propeller apm2. 8 and now I using 11.1v 2200mah battery gives me a flight time of 5 min I want to use these li ion cells can u pls help me which cells should I use and in which configuration pls help me out bro Thanks for reading
I recommend using the Sony Vtc6 or the molicel p26a in a 4s1p or 2p configuration depending on how much weight your willing to carry and how large of a pack you can carry.
Its not very smart to directly glue them together without additional insulation. the cell wrapping can get damaged very easily and then you have shorted cells.
Eh this hobby is all about risks.. hot glueing these together is still much safer and stable than a high c lipo we are use to strapping to the drone.. #sendit
With the covering on the 18650, the hot glue holding them in place, the kapton tape, and external shrink tube I'm not worried at all about the cells shorting. The ONLY place I am concerned about the cells shoring is at the positive pole. That is why I always use the fish paper insulating rings.
@@timsanders7632 I have build many li ion packs. Everything from drones to e bikes to solar battery's and I have also seen burned down battery's from Friends. Its very important to insulate the cells in series. Maybe they don't burn after the crash but later in your house. Im sorry but #sendit is a very bad idea when it comes to battery safety.
@@aerialcombat There are several different methods. The easiest is fish paper or other abrasive resistant material. You can also buy plastic spacers or even 3d print with filament that can take some heat. At least put some double sided tape in between if you don't have any of the above.
