Endless Sphere

Alan B wrote: ↑

Oct 04 2018 7:39pm

What 3D printer do you have? Most aren't large enough to print a good size battery case, unless the pack is fairly small.

I was originally thinking of 3d printing them in sections and join them together if the printer is not capable of printing the whole thing in a single shot.

Actually, I'm totally new to 3d printing but familiar with Solidworks (works related). I like to design and some were turn-key projects from concepts to complete functional ones - everything in between - and rather the whole system than individual device or part. I haven't owned a 3d printer yet, but considering one. Aiming towards Creality CR-10s (or the clone "Anet e12" around US$5xx.- local, with all the overhead) for its bigger printable size. Prusa i3 mk3 is a bit small and rather pricey in my area after all the mark-ups, tax, shipping, 2 free spools and etc.(almost US$1500.- crazy!!). That's why we are so left behind.

Any sweet model ?

spinningmagnets wrote: ↑

Oct 04 2018 7:50pm

You could print up the three corners as separate pieces, and then print the six long-thin edges as separate pieces. The five flat panels can be laser-cut?

That sounds good, spinningmagnets. Thanks for the tips - I will have to seriously give it a deep analysis.
Currently, I'm thinking of vacuum forming (to get it in one nice solid piece) the main battery compartment out of polycarbonate or ABS due to their durability & ease. Breaker, fan, charging/discharging, USB ports, key are to be directly mounted within this box to be fully functional. Later we can add the 3d-printed detachable facades (L & R) to make it handsome. Imagination to be refined. Again, this is from pure desire for design and DIY.

All this batt case builds is to be a real power pack for my MTB to climb a high mountain mission, with 50+km range and 3,000+m in elevation. Plus, the mission will inspire local people that real ebike can be their main method of transport besides the recreation it brings. I mentioned here in ES that real ebikes are hard to find where I live. Some of those 200-300w front hub can be occasionally spotted. So, I first DIY it with BBSHD kit with fun in mind. Now people start showing interests and asking about how this and that more oftenly.

Still, the cells are to be welded. 14S7P & 14S5P (or14s4p) Have not ordered anything yet. Quite some works.


Off topic question :

Is it a good idea to parallel ;

(A) Triangle 14s7p (98 pcs of LG MJ1 - @3.4Ah/10A max)

to :

(B) Tube 14s5p (or 14s4p) (70 or 56 pcs of LG HG2 - @2.9Ah/20A max)

for climbing high mountain. Or should they be the same type ?

In daily uses, only one pack will be needed.

Alan B wrote: ↑

Oct 04 2018 7:58pm

Or just build a bigger 3D printer.

See MPCNC, which can be configured as a 3D printer with a large footprint.

https://www.v1engineering.com/specifications/

Ha Ha, So I will end up building everything on my own. May be the tiny motor with super energy density, gyro-controlled bike that never tips over, shaft-driven bike, etc.

I have to seriously take a look into that, Sir.

Thanks a bunch for all the comments here. I learned a lot in ES with the helps, encouragement and inspiration from you guys.

Truly appreciate it.


P.S. the very 1st crude draft I sent to a polycarbonate forming shop for quote today :

The MPCNC can be built fairly large in X and Y, but not so large in Z. However that's fine for a battery case. It uses cheap steel tubing, roller skate bearings, and 3D printer parts. It can also be fitted with a spindle motor for CNC, laser head, etc for multipurpose use.

I have a Prusa MK3, it is a really excellent printer at $750 for the kit. It will print 8x8x10 inches so not too large.

3D printing is pretty slow for a large object like a battery box. I have much smaller designs that take 10 hours to print, a full battery box could take many days to print. I would print the corners and use Coroplast or acrylic sheet for the flat surfaces.

It may be important to mention that 3D printing requires the design to be adjusted for good printing. Knowing how to make a 3D model isn't enough - it is important to understand the 3D printing design requirements. There are limitations on the angles and curves to get a design that prints well. For example, the printing surface is flat, so a design surface that curves or steps upward is problematic. The printer cannot squirt plastic into space, or at least it won't accomplish what the designer intended. Support can be used but that has many disadvantages. Printing a hollow battery box half that is not flat on the printbed is problematic. In any case, before designing it is important to learn the process limitations and requirements. There are many knobs in the Slicer (the CAM program) that can be adjusted and need to be understood fairly well before making successful prints, especially important for 100 hour jobs. The materials also have personalities, such as ABS which shrinks and requires special techniques and printer features to print well, and is particularly difficult for larger prints and perhaps a poor (or at least difficult) choice for a battery box.

Alan B wrote: ↑

Oct 05 2018 9:37am

The MPCNC can be built fairly large in X and Y, but not so large in Z. However that's fine for a battery case. It uses cheap steel tubing, roller skate bearings, and 3D printer parts. It can also be fitted with a spindle motor for CNC, laser head, etc for multipurpose use.

I have a Prusa MK3, it is a really excellent printer at $750 for the kit. It will print 8x8x10 inches so not too large.

3D printing is pretty slow for a large object like a battery box. I have much smaller designs that take 10 hours to print, a full battery box could take many days to print. I would print the corners and use Coroplast or acrylic sheet for the flat surfaces.

Yes, the MPCNC is one of a kind & very versatile piece of equipment any DIYers should have. I wish I found it years ago, so imagination would have less limitations when come to make it happen. I really like the ZENXY table idea, it is genuinely creative with big WOW factor by itself. May be I can make it one day (when time allows).

As opened by spinningmagnets before, printing out the corners will be a very good start thus improving strength to the whole case. While the flat surface can be done better. I also like the vacuum forming idea that will make the whole compartment solid in one piece - just pick the right material and it should last through entire life of the bike. Don't you think ? Just that I will have to make another vacuum forming machine - again.

I also like the Prusa i3 MK3 but the price (my local) is prohibitive and the table is rather small. Plus I need a special permit for importing 3d printer (controlled apparatus) since our government believe that people will use it to print weapons !! LOL.

Alan B wrote: ↑

Oct 05 2018 10:16am

It may be important to mention that 3D printing requires the design to be adjusted for good printing. Knowing how to make a 3D model isn't enough - it is important to understand the 3D printing design requirements. There are limitations on the angles and curves to get a design that prints well. For example, the printing surface is flat, so a design surface that curves or steps upward is problematic. The printer cannot squirt plastic into space, or at least it won't accomplish what the designer intended. Support can be used but that has many disadvantages. Printing a hollow battery box half that is not flat on the printbed is problematic. In any case, before designing it is important to learn the process limitations and requirements. There are many knobs in the Slicer (the CAM program) that can be adjusted and need to be understood fairly well before making successful prints, especially important for 100 hour jobs. The materials also have personalities, such as ABS which shrinks and requires special techniques and printer features to print well, and is particularly difficult for larger prints and perhaps a poor (or at least difficult) choice for a battery box.

Thanks for sharing 3d printing precaution tips for beginners. I also expect a steep learning curve when start 3d printing and try to avoid it by having the main compartment built using other easier method like vacuum forming (PC or ABS) or fiberglass. Both are pretty foolproof for their durability. Then we can add 3d printed fancy panels to the compartment, as nice as we like. Let's see what it will come out to be. There are a whole bunch of other things to do now.

I sketched other things to be included in the battery case - just like them to be there for ease (if space allows). Breaker take deep space and might have to be move to side facing other than rear. Ventilation fan might be needed if expect 3-4 hours of steep mountain climb and pull high amps (almost) continuously. But might need to move to side too since it might be blocked by seat tube.


To include in the batt case (view from rear) :


Breaker (need only 1 pc) & 3" Fan :


Let me know what you think. It's good to learn from the experts.

Thank you in advance for any comments.

Bringing this topic back from the dead...

Fast forward a few years and now there are big printers on the market. I have the ANycubic Chiron with a 400mmx400mm print bed.
It is huge and can definitely print a whole jumbo battery case. Is anyone else working on this topic ??

5sx14p 21700 cell holder printing

BeachRider2016 wrote: ↑

Nov 29 2020 12:55am

Bringing this topic back from the dead...

Fast forward a few years and now there are big printers on the market. I have the ANycubic Chiron with a 400mmx400mm print bed.
It is huge and can definitely print a whole jumbo battery case. Is anyone else working on this topic ??

If you want to print out a battery case and the associated cell holders, take a look at this thread

I saw the files on Thingniverse and have d/led the files. Wonder if anyone can draw/copy the layout and box of a manufactured battery case

Hey guys, just wanted to link this here, since it's very related to this topic. I tried to fit 98, instead of 91 cells into the Reention DP-9 case. Wasn't able and went for 14S6P (85 cells). Sharing my research with you: https://www.thingiverse.com/thing:4627055