Nice video as always. I want to add one thing that is often overlooked when comparing lipo with lion. The nominal voltage of the lion cell is lower then the lipo. So for the same amount of power(watt) but with a slightly lower voltage the current is a bit higher. So with the lion pack you use more current for the same power.
All of the packs compared in the video are 4s for an easy comparison. You can add flight time by adding more cells (6s versus 4s for example) but that would potentially require changes to ESCs, motor and props to work. That isn't in the scope of this video, see the efficency video linked in the description.. Happy flying
Hi Painless. Love your vids. Completely off topic - have you upgraded your 7'' crock to betaflight 4.2? I have and I cant fly it anymore. I have burnt 2 motors and I have no idea how to tune it. And cant revert to Betaflight 3.6 as well, cos it's not supported anymore. If you have upgraded yours to 4.2 and have tuned it could you share your betaflight dump? That would be totally awesome.
Crock? I'm not sure what model you are referring to. I've flown the 7" Rekon7 PRO recently and the tune is available to download via the link in the description..
You were actually right a 7:33, it's 65mm long, 650mm would be 65cm lol.The 0 at the end means it is a rounded cell. If you are struggling to get your hands on 18650s/21700s, look at vape shops ;) The Samsung 40T and 30T are the best 21700s out there, 4000mAh/25A sustained and 3000mAh/30A sustained respectively
I have a single DIY 4000mah 4S1P pack made out of 21700 sized Samsung 40Ts. Amazing battery, I use it mainly as a Power source for my goggles, but it will keep my 4in quad in the air for 20 minutes as well.
NKON NL sells reclaimed 18650s among others. They are like new (except the weld spots) and may be available when brand new aren't. I had an electric bike shop tidy them up and weld for my config.
Wanting to build some packs with li-ion cells. Not easy to find at a reasonable price here in Canada, if at all. We have the only high volume manufacturer of cells in North America in BC. Molicel.
We are turning from lipo to li ion battery as it gives more endurance and going to give high current now days, also it safe and i use it from 2 years still its alive on other hand lipo died in a year, due to unbalanced voltage.
Thanks for the video but I too have a 2P2S battery pack that was working fine on a flying wing but during testing when I crushed, the battery on both the charger and multimeter shows that it is full but when connected to the esc it shows an unstable voltage and so the ESC is beeping that abnormal voltage thing. Please help me
Lipo batteries- every time i bought expensive lipo batt. they never lasted as the cheap ones i get, i have some cheap batteries for years and batts. like black red graphene 1500mah 4s some get soft atc, even turnigy A-spec swollen and some chinese zop power they just keep going bought them at same time little over 2y ago got mb 25cycles on them- sure little less c rating but they are still same as new. I take good care of all batt.use good expensive chargers and i charge slow 1Amp 1500-2000mah- 2Amps 3000-5000+mah- bought 2 turnigy nano-tech 3s 2.65A year ago one is already soft, still works but wt hell lol- Now i make my own li-ion 18650-21700 but still use lipos in some planes
does anyone make battery packs where you can put in cells individually like normal batteries or is that crazy and dangerous? you know like plug them in like alkaline?
@@frankyflowers the weight of the holders would be a significant factor and most of the commercially available 18650 holders have a maximum current rating of 5 amps
There's a little bit more to the story here. Your battery time isn't just based on mAh capacity of the battery pack as you say in the beginning. It's really based on Watt-hour capacity of the pack (mAh x Voltage). Watt-hours is the measure of the total energy in a pack. As an example, a 3s 2000mah pack will provide less flying time than a 6s 2000mah, understanding that the 6s weighs about 2 times as much as the 3s. Depending on the total weight of the model it could provide about 1.8 times the flight time with the same mAh rating.
I have been flying the 21700 here for a couple years. Here they are easier to get than some of the good 18650's. I built a spot welder and made up 4 Molicel 4200 packs. They are nice packs. Get around 40 minutes easy in an AR 900 and 1 hour+ in my Phoenix 2400. I have seen some people going with 26650's as well but I haven't tried it myself.
I've been using 21700 molicel packs for my LR flying and never looked back. Imagine 21700 6s1p 5000mah or 18650 6s2p 6000. Additional 1000mah is not worth double the weight. Here's how I build mine ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-y6M0QHbpC68.html
If the battery have bigger capacity even with less C rating will give the same current. Ex. 500mah x 80c =1000mah x 40c. Thanks for share . In may case I have ldark et 115 Original battery 550mah 2s 80c. Fly time 4 min. I have 1000 mah with 30c fly time 7 min. I didnt feel more sag from the battery with 30c rating. Best upgrade was to change from jst to xt30.
So to fly for an hour you'd need a more than 8000 or 9000mAh battery at that amp draw to leave 20% in the pack at the end of the flight. If we half that for your 30 min flight time then you need about 5000mAh pack or more.. I hope that helps.
I've been running these Molicel-P42A 21700's for a few months on my 7" and it works great. 6s1p gets me about 15 or so but 6s2p doesn't even come close to double it bc of the weight.
I also would like to take the plunge and get a wing but my buddy destroyed his on the first take off so I don't think my luck would be much different especially since they are made of foam lol
I ride high power ebikes (on private land with permission obviously). I have a few different li-ion packs depending on the ride. The main pack is 14s 5p (52Vn limited by the bms to 40 amps max current (each cell has a max continuous current draw of 8 amps)) 17.5ah using 18650 and the "going fast pack" 20s 4p (72Vn limited to 100 amps max by the bms (each cell has a continuous current draw of 45 amps)) 16.8ah using the pa42 molicel 21700. obviously a different use case but it shows the fantastic capacity and current draw from the slightly bigger cell size is a game changer for the use in the RC hobby and if you only charge each cell to 4.1v and discharge to 3.6v you can massively increase the number of cycles before you drop to 80% capacity. Stay safe Lee. good info from you as always.
I've been using those 1100s you were running on that babyhawk....also on a babyhawk. Really impressed with them. Got an old dart 635 that's running 2 in parallel and I'm tempted to build an 8s 5-6" quad around them. AMAZING energy density for the weight and acceptable power density too.
Thanks a lot for this overview and numbers. I really sometimes wonder how much space in your house you use for stocking up your planes. On each new model I need to get rid of one old model due to space. Probably you have some best practices for model storage to avoid storage damage? Thanks again for continuous great support.
Flying mainly wings dramatically reduces the space needed for fixed wings. Especially those that come apart for storage. Models get donated to others, passed on as prizes or given to raffles for charity usually.. Happy flying!
