So I keep going back and forth with plans on this Haya shortboard. Mainly my battery options and motors/wheels. Have a bunch of motors and it’s time to put this beauty on the street. Two rows 490mm x 91.5mm x 23.2mm as a battery compartment
First thing is there’s a few battery layouts that may be possible or may be pushing it. I have a lot of 33x60mm micro 12s bms with balancing so it allows for far more cells than usual.
More cells would fit on the bms side rather than the unity side. After subtracting put their dimensions it leaves 457mm on the bms side and 373mm on the unity side.
Battery Option 1: 12s5p of the 30q. Thats 15Ah, and 100A if you go by 20A continuous on those cells. That’s stuffing 5p in between the 91.5mm width and 7 vertical within that side.
Potential issues: This only leaves about 4 mm left vertically. In between each cell (8 areas total) there will be about 2 layers of 0.15mm nickel, and two layers of fishpaper (I’ll be using the thin bus bar method that lays on the top of the cells to save space in between the cells). Not to mention there will probably have to be a wire at the far ends to connect the two cell battery halves. This is probably pushing it right? But it would be badass to fit 12s5p in this little beast. Maybe routing out a few mm? I just don’t want to mess with this beautiful deck.
Battery Option 2: with this micro bms, I could fit a 12s3p of 30T cells. That’s 105A, 9Ah.
Potential problems: Wouldn’t have a problem fitting them in but they are so wide that I would have a hard time securing them with Velcro or any cushion.
Battery option 3: 11s4p of 30T cells. Obviously this would be the high discharge option with 140A continuous and 12Ah
Comes with the same issues as the other 30T with minimal space above and below the cells.
Maybe it’s just me as a rookie builder, but I am glad I erred on the side of more space in my Haya HB92. I had plenty of space left after adding cells, but all the wires and connectors (for my build at least) took up a ton of extra space.
If you plan on detail, I’m sure you will be fine either way… I didn’t plan as much as I should have.
If I could have any of those though? I’d have the 11S4P 30T personally… I love having more amps available, and less amps than your max is less stress on the cells. Looking forward to see what you end up going with… They are all great options for various reasons.
What is your most desired feature? Total amp output? Overall capacity?
I was debating between 12S4P and 10S5P. I made a spreadsheet to calculate things like voltage drop, amp output, max watts, etc, and ultimately settled on 10S5P just because it excelled in every scenario. Maybe try something similar? Use the lygte info battery comparator to compare voltage drop per cell at given amps, calculate voltage under load from that for your pack, find peak wattage from that, check the boxes with math. Just a suggestion.
Motors is a loaded question… I won’t go there too much to consider lol!
I feel the same way. The 11s4p of 30T cells can still get to over 30 mph with 107 wheels. I’m sure it shouldn’t have a problem with that wheel size pumping that many amps. But the issues I fear are 107 mm on those may get wheel bite but I don’t know . I could probably swing 97mm for a slower top speed. The biggest issue is that there will be only a few mm above the 30T cells in the 23mm deep enclosure. So I have little option to secure the battery in place like velcro. I could silicone them down, but I’d prefer not to mess up the nice job that was put into the finish of this deck. Even ultra thin velcro is slightly over 3mm.
For a small board I’m usually also looking to reduce weight. Stuffing it full of cells and adding yuge wheels really brutalizes the weight. Top speed is also maybe not a priority on a short board, as stability will be lower. Plus wheel bite, so huge riser. Just adding another perspective.
So any ideas on securing these fat 30t cells with very little room above and beneath? There would be room on the sides of the cells, I guess I could velcro along the sides.
a 3d printed spacer on side(s) should do the job. I don’t see the need for velcro in this board. If you want to avoid any resonance/rattling I would recommend a soft compression fit, i.e some foam on top of the cells that gets pressed down by the lid.
You could print it hollow so that you can fiddle some wires through it.
Yeah after finding out one of the bms I was after was mislabeled on the bestech website, and after playing with these fat 30T cells, I’m not going to push it. I’m just going to do a 12S3P.
It would be 15 cells (5P) on the empty side which will easily fit a unity. It’s the easiest way to arrange the cells with the limited amount of space above the cells.
I would need to take out a small amount of wood on the side with the bms. Where the bms is I would need to remove about a cm of where the wood is slightly raised. I’m hoping it will be easy enough with a dremel bur and sanders.
I may have to angle this upper corner a bit as well to get the far battery to fit higher up (since there will need to be a connecting series wire on the one side)
Not a wood guy at all. I hope I don’t somehow fuck up this beautiful board.
It’s pretty much just waiting on the unity. I have a batch one but I’m just going to wait the last few weeks for the new ones. I also have a set of hummmies that I have considered as an alternative but they’ll probably end up on the spud. I found a reasonable way to fit a 12S4P of 30T with this little bms but you have to take out a little bit of wood. You’d basically do 7 rows of 4 on one side and 5 rows on the other which would still fit the hcx-d606 and a unity. It would require about a cm of wood to be removed from the edge of the side with 7 series and the slightly raised portion to be taken down.
Now if you had cell holders, it would probably be too long and require too much wood removed. I’d like to do a bus bar style battery, but I fear I won’t have enough room above the cells. I may just play it safe and go with a 12s3p which is still like the A of a 12s5p or more of the 30Q
That was the plan at first. I have three sets of motors looking to bone a board. I figured the dd would need the most amps (especially if I ever put it on 110 wheels). Also wheelbite on some of the other decks with wheels that big. I’m a big fan of small decks so the hummies will be going on something around the same length. It’ll either be the spud I already built or something else if a similar size