I need a battery enclosure and deck. Kicktail and longboard. Any ideas where I can source this from?
I assume you found my post?
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Actually I didn’t see yours. Ever find a solution? I’m kinda pissed that @MBS still sells them like that if they know about the the issue
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Haven’t tried anything yet, no.
It’s annoying to have side to side wobble of the whole tire, even if the nut is tight.
I have no kapton tape or loctite 641 for that matter. Just regular knockoff loctite (no idea what number but it is blue)
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That’s the exact issue I’m having. I have some loctite 638 and 641 ordered that I’ll try when they come in. Also kapton tape. In the meantime I think I’m going to try Teflon tape.
I may also try using foil tape; line the bearing seat with it and work the adhesive in there as much as I can. Then I’ll see if I can get the bearing pressed in there without damaging the tape.
I’d rather @MBS just fix the issue and replace my shitty hubs.
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That failed immediately when I’ve tried it. Or I’ve used too much.
Yeeeah
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Ive got an age old question… which battery formation…
18650 Molicel p26a- --12s3p-- 7800 mah ($162) 3.63lbs 75A-105A 342 wh
vs.
21700 Molicel p42a --12s2p-- 8000 mah ($144) 3.58lbs 90A 372wh
leaning towards 12s2p bc of slightly higher wh, but i imagine some ppl would say 3p because more p is better. any quick thoughts?
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Yeah you might have used to much; Teflon tape is can be a pain to work with.
Maybe I’ll have better luck with the foil tape.
I think the true answer depends on your discharge current rate but even with that P42a would probably win because it’s a larger cell in the first place
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Those two setups perform about the same when down around 10A-12A per cell, or lower. Once you’re getting above about 15A-20A per cell then the P42A setup can perform a little bit better.
Unless you’re looking for every tiny scrap of power you can find no matter what then it’s probably more of a size/shape/cost decision.
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I’d have thought because the consideration here isn’t A per cell but per pack, that the 26a would be the (relatively) clear choice but I think I might be wrong.
My logic was - Even keeping the 26a below 15A per cell gets you comfortably in the 2000W range, at or above where most of us spend most of our time. The 42a would be working comparitively a lot harder. But when I checked out your discharge graphs, 15A P26A x3 gets to about 7410mAh, and 22.5A P42A x2 gets to around 7600mAh
I’ve seen a few logs where people do pull 100+A from a battery for reasonable amounts of time, but I think it’s reasonable to assume much much less than that unless otherwise stated. If OP does intend to run 60-80A semi-regularly then I think the gap narrows even more, and both sets of cells are outside their comfort zone
@Jburchett09 in case this helps
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I would not recommend pulling that much out of a 2p p42A pack. Mine already sags hard with 50A
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Same. I’ve got a 12s2p P42A at 50A i just ran the other day. 8 miles in i tried a hill climb and got significant sag (this is on an emtb so ymmv)
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I’m on hubs for comparison.
Oh and 10s!
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Yea, those two cells are actually quite close in how hard they are being run compared to their ratings/capabilities. And that’s critical for choosing a cell.
IMO, it’s all about per-cell current draw. That tells you how hard you are running each cell, each cell’s performance (sag, temp, etc.), and how the packs will perform relative to each other when totaling up the voltages, sag, current, etc.
We’re not able to determine pack performance without adding up the performance of each cell. But this is the theoretical pack performance, without taking into account the spot-weld resistance, nickel strip resistance, and wiring/connector resistance. These can add a considerable amount of resistance to the pack and really pull the voltage down at higher current levels.
But unless there is a big difference between how a 3P-based P26A pack and a 2P-based P42A pack was built then we can still use the “theoretical” performance comparison to choose the pack better suited for the way we ride.
If there are big differences in the welding, series connections, wiring/connectors, then we need to take that into account.
As @xsynatic and @sleepless noted though, in actual use the delivered Wh will always be lower than the calculate Wh for the pack based on cell test results because of all the other places power can be lost (voltage sag).
Agreed.
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good to hear… because i am only trying to get 8 mile range on dual 6355 street
what do you mean by both sets of cells are outside their comfort zone? I’ll be running dual 6355 street wheels. id be setting batt amps max to 65. Also trying to figure out if i need to make a bigger pack (12s3p 21700 instead of 12s2p) would rather stick with the original packs listed because of lighter weight and size
hmm, sagging hard does not sound great. you reccommend upgrading to 3p p42a? Im dual 6355, street and really just hoping to get 7 miles per charge without stressing battery too much, but i do like to go fast. only prefer 12s2p bc its a pretty light and small pack
Anybody know of any suitable 26650 li ions for esk8? only ones I could find are too expensive compared to comparable 18650/21700. also i know batteryhookup is a great place for lightly used cells but it seems its mostly lifepo4, anybody know of a site for lightly used li ions?
So there’s a couple of things
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There’s a pretty big difference between setting battery max to 65 and pulling 65 as a sustained load. As I said unless you explicitly state that you are gonna pull heavy currents a lot, it’s very likely you’ll be in the 2000W zone most of the time. Also my comment was given with “if semi-consistently drawing 60-80” which is even higher
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65A from 2P is 35A each, and mooch has tested the P42A saying that above 30 it gets too hot. He elaborates a bit more in the report, and said 30 is his rating, so 32.5 for continuous periods you’re gonna have a bad time.
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You’re a bit safer with P26A in 3P, because the low end of the range I have is 20A per cell. But as I said 80A is above the sustainable continuous rating
Reports here
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