that’s pretty fucking expensive, no?
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This is my 12s 3p Lipo battery, or 12s 15000mAh. It’s on my Mtb with dual 6374 190kv motors. I run 120 battery amps and 60 motor amps and get about 14 miles of range on MBS T1 tires with 40 psi. The packs are Turnigy 5000 mAh 20C - 40C in a 3s 3p configuration with a smart BMS for balancing and charging at 15 amps. The pack is theoretically capable of 300 - 600 amps peak based on the C rating, but those are always big overestimates. The pack cost about $350 to put together, including a $40 bms and all the connectors. I was also able to get the batteries on sale to help with the cost. I also cleaned up all that wiring before putting it in the board.
A pack like this gives pretty good bang for your buck, but it’s a pain to put it together and keep an eye on. The only reason I went this route was that I had ample space and easy access to the battery in my top mount box. Also, I used to need this board for long-distance commuting, but I will probably break up the pack into individual p groups and turn my board into more of a jump/ freestyle board now.
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How much should I be paying for one?
Wow, that looks like a pain in the ass. That is a good looking board though. How often do you have to pull it out of your enclosure? How long has it lasted you? And what kinda BMS did you need?
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It’s a pretty normal price when it’s built by a pro builder. After all you want a safe battery and the esk8 battery building standards are much higher and more time consuming compared to let’s say Ebike battery’s.
It’s around 320$ in materials and 230$ for the service. That’s average pricing I’d say.
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I exclusively use LIPOs. This is my current setup on a trampa/kaly hybrid with a bms. I also used them before on a split enclosure flexy deck. This current setup is 3s x 4 8ah each and I can take them on a plane (88wh each battery). I know it looks complicated but trust me, it is 1/10th the work of building a li-ion pack. the whole thing took me an hour while I was watching tennis at the same time. lol
Here is what I have learned. Keep the battery between 3.6v and 4.15v per cell and you won’t have any problems and they will last you a long time. 3.6-4.15 will get you ~80% of the battery capacity.
Lipos are punchy throughout the ride because the voltage stays above 3.6v. Li-ions suck once you get to 30-40%.
WH for WH, lipos give me 20% more range than li-ions. I never figured out why but I think it is because of the discharge curve. For li-ions you are going down to 2.9/3v while lipos stay above 3.6v, so for the second half of the battery, you are having to pull 10-20% more amps from a li-ion to get the same wattage as lipos.
There is some great info on the old forum by the user “evoheyax” and “namasaki”. Look at some of his posts and he confirmed what I knew intuitively but never understood it.
The only slight disadvantage lipos have is that they are not as energy dense but once you factor in the 20% extra range, even that is narrowed down.
regarding the c rating, just divide it by a third to be on the safe side. chinahobbyline is a good budget option and get descent reviews and i am happy with mine. look on the rc forums
Here is the best part though. If you look after them, they won’t puff and you can sell them on second hand. I have bought and sold 3 sets of lipos (after 30-50 charge cycles) and got 50-60% of the money back. They are much much cheaper in the long run IMO
Ask me anything else you want to know.
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Everything he just said I feel the same. 3.6-4.15 is a great voltage spread. Beats ion in having more consistent power and speed. Just don’t bang the cells. A lot easier to put together than an ion pack and a lot less possible faults and cheap.
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You mean by keeping them in the 3.6 - 4.15 range ?
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Yes. You could go down to 3.55 ONLY if you are discharging through the BMS so it can cut off if one cell goes below that but I bypass discharge so keep them at 3.6.
3.65v soft cutoff and 3.6 hard cutoff
edit: just as a guideline, get lipos where a third of their c rating will be more than the battery max on your vesc, for obvious reasons.
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Im using 4x3s zippy lipos 5800mAh since 2016. They became slightly “puffed” 2 years ago and i tighten them with aluminum plates. Im using them in single 192kv motor with top speed around 50km/a and 45a current. I will not use then in current season as im afraid now. Las year they was not getting hot during discharge. I never stored them fully charged/discarded and always used balance charging. I don’t know how sag looks like, newer experienced it. Torque is always the same. Im planning to switch to 40T 21700 in 2p config. This will cause sag, but i m tired of charging each pack separately(BMS for lipos is nor reliable for me). Maximum voltage they can store right now is ~4.18. Never discharged them more than 3.6v. Always tried to not store them at 4.20, i preferred 4.15. Not sure about range ~ 15-20km
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Any details how you compressed your lipo’s with the aluminum plates?
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I had the same dilemma. Lipos or Li-ions (I was considering vtc5a or p42a)
my setup is dual 6374, 192kv (waiting for new 149kv to change)
~215 pneumatic (little flat at 1.5bar, I like it smooth 
)
16t/72t
and since i got 2x lipo from other build I finally choose to go with additional 2x8ah 5s lipo
with this charger and pararell board to chagre it faster. (for 1c charging (only need to do it twice) i set 16a when both plugged) and only to 4.150v/cell
Barely feel the voltage sag (enough that it started to be a problem lol, cause I dont feel when it start cutoff at 36v)
The old ones (after 1kkm) are good enough to be almost the same as the new ones. They not even warm after ride in woods (but a little puffed cause i wet them once 
)
Average 16wh/km
~18km range with 8ah (36v/32v cutoff)
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I got those. Seem the ideal shape for a deck. Or I have the 2s and 3s version and slimmer. Hell of a lot easier plugging those in series than dealing with an ion pack of maybe 48 cells.
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Wow, now I’m leaning more towards lipos again. I don’t know about the BMS, I would have to get a wiring diagram. It looks pretty confusing. The series connections are pretty straightforward. If I wanted to add one or more in parallel that would make my head spin.
So I should look for around 30c? I’ve had people tell me to shoot for 60c+ now I’m confused😕 I know what the C ratings mean but which one’s better than which?
I would try to avoid paralleling. Get the Amp hours you need and go in series. If I had to parallel, I would just use 2 BMSs. Thay way, every cell has over discharge protection.
C rating without capacity is meaningless. 30c 2ah is not enough but 30c 10ah is enough for most situations.
How big is your enclosure?
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You could balance externally. AOKoda CellMeter 8 150W Discharge Module Set with Lipo Battery Balancer Sale | USA Mobile - Banggood Mobile
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30C for 8ah is much more than I need, even divided by 3 its about 80Amps cont.
maybe this will help
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This is a pretty good deal. Ovonic have a decent reputation.
2x series for 575wh and discharge for days
$200 + $40 for a BT bms and just grab a cheapo 2a charger for now. $250 dollars and this will shit on any 600 dollar li-ion pack
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My enclosure is too big so I’ll be getting a different one anyway.