SMC, has been around for awhile in the RC Car world. Reliable and decent cost.
Team Orion has some pretty powerful lipos. I use them in my RC Truck XMAXX. Good discharge rate.
Turnigy is well known in the RC world. Reliable and cost isn’t bad.
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Love myself some turnigy lipos. Kept mine at 4.1v for nearly a year and they barely puffed.
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I mean if you’re quick enough it prob gonna work.
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For sure- I’m going to bring this beast to carve next year. No street riding for me, but it’ll be fun racing on track with y’all 
If he’s willing, I’d love to see what insanity @poastoast could get up to.
When picking out these batteries, I made a huge matrix of 100+ different options, from all kinds of different companies, comparing stats like capacity, max power output, cost, cell count, company trustworthiness, etc. before I landed on these batteries.
They’re rated for 150C Continuous, 250C burst. At 150C, that’s a power output of;
(150c)(9.5Ah)(2p) = 2850A
(2850A)(3.8v)(12s) = 129.960kW. Kinda stupid and almost definitely wrong.
There’s the age-old debate if these c ratings mean anything. There’s this neat video on their youtube channel with real graphs comparing their batteries to others. (If it’s accurate) they make some good packs.
The rest of the channel has a bunch of other battery testing and debunking videos. If they’re selling snake oil, at least they can back it up with data to show it’s better snake oil 
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i could give it my best! 
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Two nights of testing down, only really started to push it tonight. It feels like this board is going to be revolutionary once it’s dialed in.
Probably important to note that my point of reference for racing around a track is my custom Kaly. After racing on channel trucks and a flexy deck, any three-link board feels revolutionary
I didn’t expect to win any awards for efficiency, but I was shocked just how BAD it turned out to be. At track today, I drained the entire battery. Average efficiency: 98 Wh/mile 
Photos Credit: @MarioChacon
Left: @HAIRYMANJACK
Right: Reggie T
Photo Credit: Lyfe of Jimmy@Lyfe_Of_Jimmy
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Lol thats wild… and its probanly only gonna go up
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Waiting to see what you can do on this monster! I want drag times, T-race and I2S Chicago track please 
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Pure insanity this thing, Acceleration must be wild!
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Yehhh 
Sad I had to miss last night but I had important stuff to deal with.
That efficiency is insane my record on 2wd is 46wh/mi over 10 miles
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whoa. i never broke 60wh/mi
i’m surprised at that difference.
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Super happy to see you finish this project. The end results were worth it. Watch out for Tucker 2024
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All of it
I don’t have an exact count, but adding up just the hardware alone reaches 6k. Probably close to 7k after including all the little bits, connectors, tools, etc that add up quickly (as I’m sure everyone here is familiar)
Timewise, easily 150+ hours, counting design and build.
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you’re not supposed to say this out loud.
my brother-in-laws father raced SCCA. He told me, i had to stop keeping track or i would have to stop doing it.
Balance Lead Upgrade
Before the race this weekend, I wanted to streamline my charging setup. I manufactured and installed two wire harnesses that connect to the balance leads, and expose them on an accessible DSUB15 connector.
Dustcap on, dustcap off.
I then made some additional harnesses that connect to these two DSUB15 connectors.
One connects the two DSUB15’s in parallel and has a JST-XH connector that connects to my iCharger x12. This, along with an XT60 added to the terminal blocks of the G300’s, allows me to balance charge all 6 lipo’s inside the board at 1000W, WITHOUT needing me to take off the bellypan.
The other one can connect to the port and quickly see the status of all of the cells. While this can be done with the above harness and iCharger x12, it would require external power to turn on. While not super accurate, This gizmo makes checking the state of cells as simple as plugging it in. Probably won’t use it much in the long term, but it’s useful when testing.
“Brief” AVS Riderfest Recap
For those uninitiated, AVS stands for Apple Valley Speedway, and is north of LA. Big track made for drifting cars. Lap times for esk8 usually range from 1min20s~1min40s. I was able to post a 1min30s during qualifying on Ankle Wreacher.(I believe the esk8 lap record was set by @MarioChacon today, at 1min11s. I could be incorrect about this)
There was a race event held here on Today(Sunday). Qualifying times determine heat race positions, which then determine access to the Final race. The races are 3 laps(lasting about 5 minutes)
Overall, I couldn’t have asked for a better first race with the board, and I can’t wait to get the kinks ironed out. Thanks to the whole SDESK8 ARD Team for being such incredible, supportive, talented teammates (and congrats to @HAIRYMANJACK on 2nd place!) Wish I had more pictures to share.
Unfortunately. I had considerable problems with Ankle Wreacher throughout the day.
The main issue is that it would overheat incredibly quickly, which significantly affected my race results. Halfway though the 3rd (and last) lap every race, I would loose significant power as the motors thermally throttled. I lost 3~4 positions in the final race because of this (such is the nature of racing 
).
Once I came to a stop at the end of the third lap, the board would barely be able to move under it’s own power until it took a few minutes to cool down. Thank goodness it only needed to last 3 laps.
While it was 90°F outside, and nearly every esk8 board was having cooling issues, none had them to the same degree as mine (pun intended).
Most notable was @HAIRYMANJACK’s board(160A motor amps each motor, Reacher 7490 165kv), had a similar setup, but did not have the same overheating issues. Notable difference is rider weight (I’m ~50% heavier) and 165kv vs 265kv.
The fact I overheat but he doesn’t bucks my intuition. I would think that having 4x motors would lead to distributed power, meaning each motor would only get ~half the heat then a 2x motor board setup, right?
Relevant Hardware grey box
12s2p 9500mAh 150c LiPo
Reacher 7490 265kv motors
22T / 78T = 3.55 ratio
Relevant vesc settings grey box
Motor Temp Cutoff Start 85C
Motor Temp Cutoff End 100C
I adjusted the beta value of the thermistor to match a Reacher motor(same value as used by @HAIRYMANJACK)
Motor current started at 100A/motor, but I lowered it to 85A/motor after qualifying in an attempt to reduce overheating (to little avail)
I should be able to push significantly more then 85 Motor amps through these motors without issue…They’re rated for 10kW; 145A continuous, 200A max.
My hypothesis is that the 22T doesn’t give nearly a high enough ratio for the 265kv motors, especially for the racing at AVS where I spent the turn-y bits of the track at 20~25mph.
If I change out the 22T pinions for 18T, it would increase the ratio 3.55 → 4.33, which would let the motors run at a higher, more efficient RPM. This might also help with the Wh/mi efficiency problem.
I’d love to hear alternate opinions about what’s going on here, and if you’ve got it, best way to fix it.
Here's a bonus screenshot of me breaking the silly 100Wh/mi barrier, taken after coming off the track for qualifying(and after my motors cooled a bit).
esk8 news calc for either pinion size, for your convenience.
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