Which Is More Efficient? 4S or 6S Batteries For FPV? - FPV Questions

[TimsDrones]

Interesting discussion - to me, either can be efficient, so long as the setup is designed for that number of cells. Technically, the IR loss per watt delivered should go down as the cell count goes up ... but weight, etc., it all comes into play.

[fabiom]

I also think that the extra power of 6s (due to higher equivalent kv) makes the extra battery weight less noticeable so people easily forget that they actually added capacity compared to their 4s setup. And about the sag: I think that 6s just gives you more "potential" that you often don`t even use on 5 inch, so when the voltage drops, you are still well below the limit the battery can provide in terms of power. In a 4s pack, you reach the limit more easily so you notice it more, if that limit drops as the pack runs down.

[SugalimeD_FPV]

4S has the advantage that you can use the lipos from your 3.5 inch 4S copter on your 5 inch copter by connecting them in parallel. 2x XT30 to 1x XT60. And tie the batteries well with a ribbon. Since you can't get small 6S lipos and you don't normally build a 3.5 - 4 inch in 6S.

However, the method would also work for 6S! I mean building your sub250 quads 3 - 3.5 inch for 3S (with the corresponding motor KV) and for your 5 inches just connect 2x 3S batteries in series rather than parallel. The problem here, however, is the battery cables, which are designed for an XT30 plug. This means that the same current flows through a battery as from the entire battery. When connected in parallel, both batteries share the current. So in principle it would only work if you have a sub250 3 - 3.5 drone that flies 3S XT60 Lipos. For example, there are 3S XT60 Lipos on the market in 850, 1050, 1050, 1300, 1550 mAh.

PS: With parallel you can add the mAh together. When in series the mAh stays the same but the voltage doubles...

[Selfmade]

I always fly 1500mah 4s, just recently built a 6s quad and have 1300mah 6s and i was actually getting 1.5-2 min more flight time as per my osd timer.

[SugalimeD_FPV]

I live in Germany (Market). Most available 6S lipos seem to be for heavy 5-inchers. The most available sizes are (2024-01-05):
* Tattu R-Line 6S 1200 mAh (197g, 52€)
* Tattu Funfly 6S 1300 mAh (215g, 31€)
* Tattu R-line 6S 1400 mAh (223g, 51€)
* Tattu Funfly 6S 1550mAh (260g, 46€)
1050 mAh is really not available. 1200 mAh is the smallest 6S battery you can buy (SFAIS).

In comparison with 4S you get much cheaper and more available lighter lipos.
* You get 4S 350, 450, 650 mAh as well...
* Tattu R-line 4S 850 mAh (92g, 21€)
* Tattu R-Line 4S 1300 mAh (150g, 21€), same energy like 6S 866 mAh
* Tattu Funfly 4S 1550 mAh (181g, 21€), same energy like 6S 1033 mAh
* Tattu R-Line 4S 1800 mAh (197g, 39€), same energy like 6S 1200 mAh
* Tattu 4S 2200 mAh (223g, 30€), same energy like 6S 1446 mAh

I plan to build light 5 inch racing drones that do 3D freestyle, with a light Runcam Thumb Pro or later perhaps digital onboard recording. E.g. with the Five33 Lightswitch V2 frame and TWIG ET5 frame. Somehow I don't like the situation on the market for 6S, because there are only very heavy batteries and they are significantly more expensive than 4S.

IMO 4S 1300 - 1550 mAh is perfect for a lightweight 5 inch freestyle drone. That means 6S 850 - 1050 mAh would be perfect as well, but they don't exist on market... Racers fly with these heavy 6S 1200 - 1300 mAh lipos ?

[Bri]

Love this video. I used to fly both 4&6s. I prefer 4s 🤷

[CarbonGlassMan]

With 6s the demand on each cell is probably 50% less than it is on a 4s pack. So a full throttle punch near the end of a flight on 6s is probably demanding what a 75% throttle punch on a 4s pack demands. Just a guess.

[theduck]

There are optimum voltages for every sizes of quads. It is a compromize of 1) size and weight of the electrics because of voltage arc and leak insulation and between 2) the weight because bigger wiring and windings and cooling because of high currents because of low voltage...

[TattedTommysTv]

So I'm safe to run my 4s on my 6s geprc 30 right I know it will be under batteried but also does it hurt or do anything negative to the quad when you run 4s on a 6s and you ask why cause living room stunts lol you guys rock

[MrCoffis]

I have experienced the same thing. I fly longer on 4S since it has a higher amount of energy per gram because of the lower number of cells. Theoretically higher voltages result in less energy loses due to lower currents and heat generation but I guess those effects only become substantial when you are talking about kV (kilovolts)

[zappex]

Best lipos for 5 inch drones, Tattu 4S 1300mah, 1550mah and 1800mah 🫡

[Pintosonic]

To me on a 5 inch 6S gives me a more constant performance throughout the flight but not longer flight time. On 4S after one minute and a half we clearly feel that we have less power and we must take that into account. It’s kinda of annoying for some manoeuvre like power loops and dives. After a run, on 4S the packs are always hotter than on an equivalent 6S quad because the 4S pack has to give 50% more current for the same amount of power. I can get much more charging cycles out of my 6S packs than my 4S used to. On 4S i could barely make a season of flying before my packs look like balloons ready to explode.

[PerchEagle]

In case of a terrain robot, should I go with 12V or 24V battery system ?

[SugalimeD_FPV]

I see a big disadvantage in 4S compared to 6S. You need the 50% more powerful electric current ESC. Which are usually significantly more expensive. For a 5 inch with 2207 motors e.g. a 65 amp and not a 45 amp ESC.

[PhoenixBoy]

Good information. What is 4s and 6s, I am a newbie and trying to explore battery for my DIY electric paramotor project.😊😊😊😊

[Dragny]

If we're talking about real world dollar cost, then the answer is whatever is currently less popular. The product with less demand will usually be priced lower per Wh. Almost all sales on CHNL are for 4S packs.

[TechnicallyTom]

Theoretically ohms law says that current has a greater effect on power loss due to resistance but I think the real reason you may get better run times on 6s is that the battery sizes do not match up for capacity. If you switch from 1500 4s to 1300 6s, you have switched from 6000mah to 7800mah total capacity of all cells if they were wired parallel. Ohms law may not have a significant effect and I agree other factors might give 4s more of an advantage but I would expect that swapping out for a higher capacity of all cells added together to be what might give better battery times. Also, why no audible voltage alarm on the transmitter announcing your voltage when it gets low???

[raikagenu]

I have interesting question for you, if i have 12 pcs of 18650 Li-ion battery, which one is better configuration 6S2P or 4S3P ? thank you

[oneRella]

Did you compare packs with the same amount of watt hours? A 6s 850mah pack has more stored energy than a 4s 850mah pack.

[GRZY.A]

Quick question ⁉️ ⁉️ ⁉️ I have arris 2306.5 1500kv motors on 5 inch racing drone. It says to use 4s lipo. Can I use 3s lipo? And what will be the difference while flying?