Earlier today I joined the community and I’m happy to see all of the cool builds around so far.
I’ve spent a number of hours on reading forums such as this and electric skate builders…alongside other articles and youtube videos. Despite all of that, I feel as though I have a mountain of knowledge to uncover. Anyways, to the point, I want to construct a little Univesity board to help me get around campus. I don’t want anything crazy and I’m broke-ish so my budget is going to hover around 700 or a little more.
I’ve spent some time compiling parts, shoving that into a little google sheet below. I’m hoping that I can get some feedback on whether or not these may be compatible parts and if this board can work out. I’m open to any suggestions for different parts if there’s a better deal or simply better quality overall.
I’m still looking stuff up for battery construction overall but I get the gist and will have a helping hand in the near future.
I’ve used these and found them to be quite good, but a decent bit of soldering is required to make them work with common sensor wires and likely your remote
Fortunately, makerx includes all the cables you need
I’m not sure that $95 for a 12s2p 40T pack is realistic, even if you are building it for yourself. That’s ~$4 per cell, which pretty much only covers the cells even if youre getting them on sale. There’s a lot of extra costs that creep into the battery building process like nickel, wire (of various gauges), BMS, charge port, connectors, heat shrink, fish paper, etc etc etc. Not to mention any tools you don’t already have.
Even if you’re using someone else’s spot welder, I would expect to spend around double what you hqve currently budgeted just on materials alone.
Also, the Molicel P42A outperforms the 40T for only slightly more $ per cell.
But it seems like you’re on a very tight budget, so I would highly suggest looking at the “used parts” or even “completes” category on this forum and picking up some gear used. Since you’re from the US, there’s nearly ALWAYS someone selling a used drivetrain, battery, board with enclosure, low power ESC, etc. on here. Buying 2nd-hand is how I manage to keep most of my builds from not exploding in cost.
I feel like you get a significant upgrade from the rando bms cooties for $15. I don’t trust any of the cheap balance bms but i have trauma. I was riding the shit out of my board and charged it sometimes twice a day. This got my cells out of balance but I couldn’t tell. rebuilding batteries because they didn’t balance and went into under voltage death sucks and gets expensive…ymmv but I know i can’t count on myself checking periodically on the battery health if it’s not convenient.
Alternatively, If you want to switch to 10s i have some 30a daly balancing bms (no bluetooth) ill send you for just shipping, ill toss in a few xt60s as I accidentally bulk bought some and you can use them for charging connections would save a couple bucks on connectors, maybe charger, and bms but imho it wouldn’t affect your topspeed/torque/amperage significantly
haha, thank you this helps. Yea, I should’ve added a note there for the battery. I am still looking into the battery process so I understand there are the extra costs, I was looking at the cells themselves for the cost, but thank you for the suggestion! I’ll look into those cells as well
Oh man, yea I was uncertain about bmses and what would be nice, but thanks for the suggestion! I’ll consider a 10s after I do more reading on both, initially I wanted a 10s so I may just swing back down I appreciate the offer, will think about it <3
Also, I have a small question in regards to BMS, does the amperage really matter? Does it play a major role in the charging/balancing process or is that if you want to do some discharge through the bms type of thing instead of bypassing it and using the VESC instead? Thanks
Every BMS has two amperage ratings: Discharge and Charge.
The discharge rating is usually higher than the charge rating. If you are wiring your BMS “charge only” (AKA “bypassed”) then you only need to pay attention to the charge rating. It is very important to never exceed your BMSs rated current for charge or discharge, as that can result in damage to your pack.
I will add that bypassing the BMS discharge also means if you leave your board turned on by accident for a few days or more (without being on the charger) you can destroy your battery.
would save a couple bucks on connectors, maybe charger, and bms but imho it wouldn’t affect your topspeed/torque/amperage significantly