I don’t recall, but yeah I’m waiting for the 30T or 40T looks maybe even better… Not sure which to go with… Have you seen the 40T specs?
Yea but it’s still not available
30T vs 30Q
Cons •42% larger volume. •47% heavier. •100% more expensive (This is assuming that 30T can be sourced at less than $7 per cell which is unlikely, more likely is these priced at ~$10 at least for a few years)
Pros •9% more energy at 10A •Same energy with 30T at 30A and 30Q at 7A (10Wh) <Still the difference between the two at same current is less than 10%> •30T gets the same voltage sag as 30Q when running 20A vs 10A. •30T runs 0.1V higher than 30Q at 10A due to voltage sag resulting in 3% higher power output at same current. •30T runs cooler than 30Q
3P30Q vs 2P30T 30T is 5.3% smaller in volume 30T is 1.1% lighter 30T has 27% less energy 30T runs ~0.05V higher @20A & 30A total (Still has higher power density) 30T is 25% more expensive (This is assuming that 30T can be sourced at less than $7 per cell which is unlikely)
4P30Q vs 2P30T 30T is 29% smaller 30T is 26% lighter 30T has 45% less energy Same power delivery through most of the range (30T still has higher power when under 20% charge) Same price. (This is assuming that 30T can be sourced at less than $7 per cell which is unlikely)
I honestly don’t see it. If you need that much power, Lipos are more power dense at nearly the same energy density (I have to check on this) at much cheaper
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From my opinion, if anyone wants more than 60A from 18650/20700 is playing with fire… Current is not scaling so nicely as you imagine, if you put 2 cells in parallel it does not mean the current will split 50% each can be 70/30 everything depends on the path, every sharp corner makes a problem and etc. I suggest using Li-Poly for high current builds.
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Yay and nay.
Yes it may not be 50-50 but 70-30 is a gross exaggeration. You are talking about 41% higher resistance in one path than the other…
It all depends on the construction of the pack. I make packs that deliver upwards of 130A continuous and burst up to 500A with 18650.
Can it be done safely? Yes Do I trust most members of this forum to do it safely? No But that’s up to them to decide…
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There are a lot of variables on that but it’s possible 
But yeah high current paths on DIY packs without knowledge is a bad thing 
That’s why I always suggest going for High C rated LiPos so at least cell will hold current As many people don’t use BMS protection.
High C rating packs isn’t any safer if the builder sucks.
Dont even remind me. And for the stupidest reasons too.
I mean simple thing ESC mosfet dies bridges motor on + and - same time, bamn 300A incoming and boom you are pack is on fire Because everyone puts oversized wires and connectors when if they had lower rating they could be like kind of protection from high current but now lets go we need current
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But dont you dare put a BMS or fuse in line! It wastes too much space! Moar Wires!!!
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Did you make a write up on how to build a batterypack correctly? I thought so but upon searching I realize that it might have been someone else.
You really should though, I’m building my first big battery pack(second pack) and there is so much contradicting information…
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But you have a battey on your backpack right ? So you don’t rely on those cells for range… just for discharge… for me the problem is range /money the 30Q is unbeatable for this
Exactly I rely on them for discharge. That’s why every cell Has it’s own application
I’ve thought about it a lot but I do not have the time to do so, plus nobody here has access to the same equipment I do.
I may do a guide on my next build with things commonly accessible. The issue is that it takes so much longer and I’m lazy lol. I’ll tag you in it if I do decide to make one
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Yeah I get that it takes time to make a sufficient guide, right now I’m mostly taking tips from endless sphere where they(atleast to me) seem to have knowledge.
Please do tag me, I’ll post some battery build pics in a couple of weeks when I get the BMS, would be sweet with some input.
How do you make a pack that runs 130A with 500A bursts?! What kind of motor would need that much power and how does that not fry the VESC?
I’m not using VESC. 
Airplanes use a lot more power than esk8…
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Oh right on. It’s there any airplane ESC you can think of that would be useful for Esk8 at 14s-18s or so?
Plane escs don’t usually have brakes
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Oh, damn, those are pretty important, lol…
None for under 2k a piece. We work with custom ESCs. This is for applications way different than esk8. We’re talking about 100lbs airplanes.
MGM Compro does have a line of car ESCs for 16S-24S but again, you’re talking about 1k each or so.