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18650 lithium ion batteries

#22
Tearing apart laptop batteries for the cells is a gamble at best, they have been used & abused for who knows how long. If you're only getting ~2000mah batteries, then it's not worth the weight penalty.

I use these for all kinds of things, from powering FPV ground station equipment, external supply to my Crossfire Tx, and long-range duration flights. I do build my own packs now, but I've done the research and gotten the correct equipment to do so safely and with quality cells.

https://www.imrbatteries.com/ is a good source of non-fake cells. The recommended method of building packs is spot welding nickel strips as hand soldering can damage them, reduce capacity, and maybe make fire. Speaking of fire, any battery with fire in the name is trying to tell you something! Max reliable capacity for 18650 cells is 3500mah, while slightly larger/heavier 20700 ones are 4250mah. There are a few oddball ones that claim higher, but with a low ampacity that makes them about useless for RC hobby use.

For a standard park flyer, these are likely a poor choice due to the high current draw. They are great for endurance and long-range flights where the current draw is kept around 4-5 amps. If you fly at or near the rated ampacity of the cells, you won't see much benefit due to voltage sag. They will handle the high amp spike during launch fine, just keep it as short as possible. I've had good luck with li-ion packs in smaller planes such as the ZOHD Nano Talon and Volantex Ranger G2, one hour flights are easy. I also have built a 3S 3P with 20700 4200mah cells that gives a 2m pusher FPV plane about 1.5 hours or more.

Charging is the same as normal lipos, but at a max rate of 1/2C. Discharge can safely go down to ~2.5v/cell, so you have to test your ESC at the lower voltages to ensure a lame voltage cutoff doesn't put your plane in the dirt before the battery is done.

Titan batteries make OK packs if you want to try these out, even if they don't work for your plane, they still are great power sources for other battery operated stuff.
 

Chuppster

Active member
#23
I am a newbie in this hobby
which trainer would support this weight and with what engine and propeller configuration
IF you got 18650 batteries that can deliver 20 amps, you could probably fly something like the Tiny Trainer or Simple Cub just fine. Get something like a PropDrive 2628 1200kv with a 9x6 and it should fly quite well.
 
#24
Thank you
I have a Tiny Trainer built and in my first attempt I have already broken two propellers
with a 2205 2300kv 6x4,5 2 blades and 3s 850ma
I will continue trying and also try your advice
2 or 3 cells 18650?
my lg hg2 give peak 30A
 

sprzout

Knower of useless information
Mentor
#25
ReadymadeRC sells 2S and 3S packs for use in their Strix Nano Goblin with XT30 connectors as well as single cells. They put a lot of effort into finding ones that would work well.
https://www.readymaderc.com/products/details/strix-power-stix-3200mah-2s-18650-li-ion-xt30
https://www.readymaderc.com/products/details/strix-power-stix-3200mah-3s-18650-lithium-ion-xt30

Cheers!
LitterBug
I've got one of those for my Nano Goblin - they claim 30 min. flight times on the battery, but I haven't been able to get up to that time yet. After about 6 minutes or so of it zipping around (and I do mean ZIPPING; it's fast!) I start getting the nervous shakes and worry that I'm going to lose it over the heavily wooded (read: full of poison oak/sumac) area just northeast of our field. So I tend to bring it in around 6 minutes. :)
 
#26
Tearing apart laptop batteries for the cells is a gamble at best, they have been used & abused for who knows how long. If you're only getting ~2000mah batteries, then it's not worth the weight penalty.

I use these for all kinds of things, from powering FPV ground station equipment, external supply to my Crossfire Tx, and long-range duration flights. I do build my own packs now, but I've done the research and gotten the correct equipment to do so safely and with quality cells.

https://www.imrbatteries.com/ is a good source of non-fake cells. The recommended method of building packs is spot welding nickel strips as hand soldering can damage them, reduce capacity, and maybe make fire. Speaking of fire, any battery with fire in the name is trying to tell you something! Max reliable capacity for 18650 cells is 3500mah, while slightly larger/heavier 20700 ones are 4250mah. There are a few oddball ones that claim higher, but with a low ampacity that makes them about useless for RC hobby use.

For a standard park flyer, these are likely a poor choice due to the high current draw. They are great for endurance and long-range flights where the current draw is kept around 4-5 amps. If you fly at or near the rated ampacity of the cells, you won't see much benefit due to voltage sag. They will handle the high amp spike during launch fine, just keep it as short as possible. I've had good luck with li-ion packs in smaller planes such as the ZOHD Nano Talon and Volantex Ranger G2, one hour flights are easy. I also have built a 3S 3P with 20700 4200mah cells that gives a 2m pusher FPV plane about 1.5 hours or more.

Charging is the same as normal lipos, but at a max rate of 1/2C. Discharge can safely go down to ~2.5v/cell, so you have to test your ESC at the lower voltages to ensure a lame voltage cutoff doesn't put your plane in the dirt before the battery is done.

Titan batteries make OK packs if you want to try these out, even if they don't work for your plane, they still are great power sources for other battery operated stuff.
I have a glider that I fly all the time, and at Flite Fest 2018, I got up early and flew it for exactly two hours straight with a 10.4 Ah battery. That would average me pulling 5.2 amps continuously. I just wonder how much more flight time shaving a few grams off because of battery weight would help...
 
#28
IMO the only ones worth buying are Panasonic and Samsung. Any of the Efest, trustfire etc brands are just bought from Panansonic or Samsung because they didn't meet specs. Canvape and Dashvapes have them in Canada, not sure about other places.