Custom Battery Packs? INTERESTED?

No, it's fine. We're talking about batteries.

Personally, I prefer one plug charging setups and custom size to fit our specific space with built in on/off switches. Lipo's don't offer that (not that you can't add it in).

Plus I have so many sets of packs and to be honest they just don't last that long. I'm hoping Lithium Ion cells last 2-3 times as long as my current lipo packs.

With a BMS on board. I would assume and hope that cells are consistently being balanced. Also I can charge a pack at 2A rather than the 15A that I charge my lipo packs at.. since I don't have to babysit my charger from a fire.
 
@torque.

It looks like your BMS PCB is tiny... how is it made? Is the pcb layers stacked to make it more compact and put on it side to better fit with the cell size? What are the PCB dimensions? How many amp is it?
 
It's pretty small.. 5.75" width and 1" height. PCB is about 10mm maybe if not less in thickness.

I'm not sure exactly on how it's stacked. I believe they have the BMS PCB's in different sizes. I wasn't exactly sure which one they were going to use but this one is nice and small. It's rated for 30A, 100A (3sec). They have the bigger ones which are used for bikes. These smaller ones I think are just to save space but I could be wrong. I can find out if you want.
 
Hey guys, so I build longboard externally to this and looking into designing one with an integrated battery enclosure. I will be running it as my regular electric with the 5s lipo I already have and use for other stuff, but would design the deck as optimised for some 18650 cells and just run some foam to get a snug fit for the lipo before getting the 18650's myself.

So the question is how many cells do I make it fit? Given the 18650 are 3.1-3.4 amps, I'm thinking 21 so you can either run a 7s 3p (25.9v 10200mah) or 10s2p (37v 6800mah) or any smaller denomination with some foam packing. Do many people feasibly need more power/range than this offers? Torque, how many cells are you going to be making these packs in? Would only be sensible to make it fit your packs when they become available.
 
What kind of enclosure are you making? What material?

I'm not too sure yet. I'm using Samsung 2200mah 18650 cells as they have a higher discharge versus the 3400mah cells. I'm thinking of solely focusing on a 10S setup as the price isn't that far off perhaps about $80-$100 difference but the added power means a lot but who knows. However, I will be getting 7S3P for (25.9v 8.8ah) which will be stacked 2 rows high. I have 14" long 7" wide and 1.81" height.

I don't technically have a solid setup ATM which I want to keep. 10S pack might have to be a bit longer.

I like the idea with the foam. That was originally my idea. Since there are so many different setups and everyone's setup differs in a certain way. I personally want their to be a bit of room within the enclosure which I can use at a latter time to add on other accessories or modifications if I need too. Of course, using foam to fill up the empty spots and cushion everything.

Something similar should be fine 14" long 7" wide 1"-1.8" tall. A bit longer for some people but the smaller might be a better option.
 
I'm still not understanding 7s as being a default minimum, vs 6s. It just seems like it overly complicates things given the 1s difference, which makes those of us using 6s-rated ESCs and chargers SOL.

Regarding your double-stack layout - will that allow the batteries to cool effectively enough? My vote is always lower profile. We have lots of usable length under our boards, so I think it should be used if it means shorter height.
 
We don't use the total maximum amps for the pack so it should remain relatively cool. The 7S is default minimum for me as they are the ones that come with CE/ROHS certification on their chargers as it is one of their standard products, 6S is not.

To be honest, I'm moving away from 6S/7S and going back to 10S. 10S is better for both worlds. We can have a higher gearing ratio for great torque but still have an awesome top speed. I've been riding 6S for so long and might have just gotten use to it but it's not enough power for throttle fun.

There's a reason Evolve uses 36v, Boosted uses 42v. If you go higher voltage, you won't want to downsize afterwards.

To have the option of creating your own custom pack. I don't see the point in going 6S unfortunately when you can go higher since it is a custom pack. The prices arent' that far off for higher voltage.

As for lower profile, you could go lower but your looking at 12" long (+electronics) for the pack versus 6" long. It's all personal preference.

Let me know what you think.
 
drmacgyver said:
I'm still not understanding 7s as being a default minimum, vs 6s. It just seems like it overly complicates things given the 1s difference, which makes those of us using 6s-rated ESCs and chargers SOL.

Regarding your double-stack layout - will that allow the batteries to cool effectively enough? My vote is always lower profile. We have lots of usable length under our boards, so I think it should be used if it means shorter height.
Click to expand...

The 7s3p was an example of what will fit, I was intending on making it fit 21 cells, but a person can easily use a 6s3p or whatever combination they want that is no more than 21 cells big. Any extra room can be filled with a block of foam to stop bounce. So basically if you wanted, you could use a single cell and a whole lotta foam. Alternatively fit in some standard, soft cell lipo batteries and some foam spacers.


torqueboards said:
We don't use the total maximum amps for the pack so it should remain relatively cool. The 7S is default minimum for me as they are the ones that come with CE/ROHS certification on their chargers as it is one of their standard products, 6S is not.

To be honest, I'm moving away from 6S/7S and going back to 10S. 10S is better for both worlds. We can have a higher gearing ratio for great torque but still have an awesome top speed. I've been riding 6S for so long and might have just gotten use to it but it's not enough power for throttle fun.

There's a reason Evolve uses 36v, Boosted uses 42v. If you go higher voltage, you won't want to downsize afterwards.

To have the option of creating your own custom pack. I don't see the point in going 6S unfortunately when you can go higher since it is a custom pack. The prices arent' that far off for higher voltage.

As for lower profile, you could go lower but your looking at 12" long (+electronics) for the pack versus 6" long. It's all personal preference.

Let me know what you think.
Click to expand...

Cooling is something I hadn't really seen as an issue, so good to hear you agree torque. I will look into it more, without compromising water resistance. I was thinking of laying them single depth 3 wide, using that great length of board that drma noticed. I completely agree with the high voltage aspect. Voltage = power. My current build is on 6s because that's the easiest for parts, but I'm also building it so it can be bumped to 10s when the vedder controller becomes a viable option. More future proof.

torque, why might you be against a longer battery compartment? the way I see it is that we have a solid 600mm between the trucks, easily enough to place 7 18650 cells long, with a bms and charge gear or other electronics in with it. Or alternatively, run soft cell lipo's instead. With the right setup, even a long pack would allow flex in the board.
 
Around 550mm long, seven 18650's cells come in at around 470mm long, then an extra bit for wiring and stuff to fit in, don't want it to have visible wires anywhere you don't need it.

For an idea as to what I was planning, just went out to the shed and snapped a few pictures of a similar low density core build. This one is 18-19mm thick in the centre. Should be able to use similar technique for the electric based build.

View attachment 1

up_002b.jpg

Trying to find some time to cad it up, but it's kinda that time of the year...
 
Should be getting a shipment of new aluminum enclosures - 14" length, 6.27" wide, 7.48" wide w/ flange, 1.81" height.

Will test this out and see if it's worth keeping and/or changing. Still wondering about the ability for flex.

nadLdc4.png

FeImCtM.png

lkPd2BX.png
 
Very clean, I don't imagine they would flex at all though. Maybe if you flared the vertical side panels out to sit at 60 degrees or something you might get a little flex. Alternatively, have you thought of putting a sheet of plastic over the top of the box, where the board normally covers and using a few rubber washers as spacers to hold the box offset from the deck a bit? Looks like you have room for the bolts to shuffle around a bit as is and the washers would stop any rattle or unwanted bounce.
 
nice one - if you just put a rubber band foam (like the one you put on windows to avoid temperature or wind coming in), this will close the gap between the enclosure and the deck concave and also provide 5mm of flexibility, and maybe also reduce vibrations. Looks neat. Where did you get this enclosure ? custom made?

I spent so much time in this forum, looking at everyone creation, inspirations that next step is for sure a 3D Printer !
 
bandaro said:
Around 550mm long, seven 18650's cells come in at around 470mm long, then an extra bit for wiring and stuff to fit in, don't want it to have visible wires anywhere you don't need it.

For an idea as to what I was planning, just went out to the shed and snapped a few pictures of a similar low density core build. This one is 18-19mm thick in the centre. Should be able to use similar technique for the electric based build.

View attachment 1



Trying to find some time to cad it up, but it's kinda that time of the year...
Click to expand...

Ever make a carbon board? I'm getting ready to make the gamble of doing it myself. Can't decide on how I want to set the electronics in it. Routed a nice new 9ply thick wood board intending to make a clamshell kinda lid and replaceable 5ah lipo pouches but with the bms it seems things are worth sealing in with some screws and easier to construct...and easier to maintain.

How slow to charge with your bms torque? Is a bms limited in this regard compared to a trad charger?
Is it the case that with the higher volts in the watts equation, so less amps for the same watts, things run cooler?
I read that the esc stays cooler at its higher wattage levels...so the faster youre going the more efficient the esc and cooler it keeps.
 
Yeah, this is more of a test. I may space them out and/or use different material. I'm probably going to put foam underneath the board for space as you mentioned. Hoping it would allow for a bit of flex.

I doubt it would flex all that great but willing to see. I was thinking something similar to Zboard. I don't think their board flexs at all if any and I see quite a few in SF. Shouldn't be too bad since it's pretty bad here as far as no flat streets.

Perhaps may look into a Carbon Fiber setup but it wouldn't change much as they are pretty stiff as well.

@Bandaro - Get your CAD up. I'm sure, we're interested in more enclosures.

@okp - Definetly, going to put some sort of dampener of foam/weatherstrip tape in between the deck and enclosure. I'm hoping it will still allow for a bit of flex.

@Huminna - Partly the reason why my enclosure will be pretty much 100% enclosed. As you know, it's been raining out here in SF and it's pretty nasty/dirty. I want it to be easy to simply wipe down my board to clean it off.

As for charging.. it charges at 2 Amps. 8800mah pack 8.8ah/2 = 4.5 hours for a full charge from empty. I think that's the right calculation. With a 4Amp charger - You can charge 2.2 hours for a full pack. Slower than my normal charging rates of 10/15amps on an rc bulk lipo charger.

To my understanding, yes. Higher voltage = less amps to reach a certain amount of wattage. Versus a lower voltage has to pull more amps for a certain amount of wattage. Wattage defined by how you pull the trigger. That's one reason for these custom packs. Most lipo packs at 8s/10s (5S/6S) are thick in height as well. Much more benefits :)

WaEc64Z.png

Waterproof Cable Glands

ESC stays cooler at higher wattage levels I think because we really only pull the total amps from neutral to full throttle once you coast to speed the amps drop down as you don't need added power to bring you to speed. This would be true. I think to a certain extent. If you stress the motors to reach higher wattage levels then no it wouldn't work. I think. Once again I'm not no EE. I'd be happy if a real EE would verify if I'm wrong :mrgreen:
 
Hummina Shadeeba said:
Ever make a carbon board? I'm getting ready to make the gamble of doing it myself.
Click to expand...

Yup, that one you quoted is carbon, running 200gsm uni and 300gsm triaxle on the underside (pictured). A lot of my boards are carbon, it has that "wow" and custom made, hand crafted factor more than a typical wood deck.


Perhaps may look into a Carbon Fiber setup but it wouldn't change much as they are pretty stiff as well.
Click to expand...

Must disagree there - having made little desktop catapults than can bend back over themselves, carbon can be flexy. Depends entirely on the specific layup used. You don't want any composite parts to flex if they have a foam core, and any can flex with a timber core, so the flex depends entirely on the layup used. I use multiple weaves of carbon on my boards to reduce flex, but some are still designed to be quite flexy. Really, anything can be achieved with the correct layup. But if you have an extruded U shape, you will get distortion to some extent regardless of what material you choose.

I feel waterproof is a must have feature too, while you don't want to skate through puddles normally, I have been known to hit the odd one... Especially when I was living in Dublin.
 
I am good with the $300 if the pack is lifepo4, has bms and has a single charge lead.

Life of battery will be twice that of lipo packs so really we are talking about a $100 delta.

If I don't have to take the pack out and can charge with a cheap single mission charger $100 is worth it.
 
kentsfreeman said:
I am good with the $300 if the pack is lifepo4, has bms and has a single charge lead.

Life of battery will be twice that of lipo packs so really we are talking about a $100 delta.

If I don't have to take the pack out and can charge with a cheap single mission charger $100 is worth it.
Click to expand...

True.. with LiFePo4 we wouldn't get 36v 8ah though. It would be a much smaller pack for the same size. Going the LiFePo4 route would be less voltage + less capacity but 2000+ charge cycles.

It's just tough shipping them out.
 
i thought you guys were going with LI-ion? lighter, cheaper, smaller in size and more voltage per cell.

true to the fact if it cost double what lipos cost its still worth it.

i know this might sound crazy but did anybody try contacting LG to see if we can buy the li-ion cells from them? they make thier own with a high c-rate and its always cheaper to get it from the makers themselves. we would have to set a very large order but if we do 8s 10ah packs thats like 40 cells per pack. if we have 25 orders we got 1000 cells to buy!

im definitely missing something!
 
You must log in or register to reply here.

Similar threads

G
    • Like
Offering Battery Assembly
Replies
3
Views
1,683
professorkaos
P
craciunptr
    • Like
    • Cheers
Launching the Kit Version of the Ride Colibri M22 E-Motorcycle
Replies
14
Views
924
craciunptr
craciunptr
vladrov
Commuter E-Bike: Grin All-Axle Hub Motor with Detachable VESC & 27s3p P45B Battery Pack in One Box
Replies
19
Views
2,987
tigcross
tigcross
FlexiRex
One BMS with multiple parallel packs?
Replies
7
Views
1,391
lnanek
lnanek
DaLanMan
    • Like
Battery Packs...
Replies
7
Views
1,781
DaLanMan
DaLanMan
Back
Top