[Maviryk]

+1, but the way he approached it was pretty dick.





So help me understand this guys...

Difference between using "capacitive discharge welding", and a high powered soldering iron, is just that we will degrade the lithium some because of the heat applied, right?

Maybe it's because I've only gotten 3 hours of sleep over the past two days(three projects, a paper, and final exams coming up), but I did not mean to come off as a dick. I apologize if I did but it was not my intention.

And yes, the high powered soldering iron will degrade the cells due to the heat. It doesn't matter much for the RC guys, but for us, we draw a LOT more juice from the batteries than they do when we start over the bikes.

 

[SEBSPEED]

Yeah I am not here to talk to shit to anyone. If I was a dick I would have posted something on his for sale threads saying what a fucking rippp, but that would just be plain gay. To each their own. I have been running my battery pack since I posted it on my build thread. Probably about a month. I haven't had any issues with the simple parallel pack. These are the same batteries used in RC's, and DeWalt packs.

Yeah, that would be pretty gay, seeing as how Speedcell makes the same battery pack basically the same way, and charges double what Mav's charging us. AND, they will NOT tell you shit about how they build it or give you tips on building your own - now that's a capitalist dick for ya!!

I don't have anything against either one of ya, I posted a less-descriptive how-to months ago about making one of these from DeWalt cells.

No need to bicker here - those that can, will. Those that can't, will hopefully read the info from BOTH of you guys and not hurt themselves trying it on their own. Or, they'll buy one from Mav or MOTY and save an assload of money vs buying a Speedcell... :shocker:

 

[SEBSPEED]

Capacative discharge welding = spot welding. Arc passes from one electrode to another w/ the workpiece in between. Welding happens very quickly and puts minimal heat in the workpiece. We do a lot of it here on aircraft parts.

Short burst of intense heat that cools quickly is less harmful to the battery than the prolonged heating and cooling of solder. Not to say that soldering can't work well, but anyone attempting this should have some practice before trying to learn on the battery!

 

[Phoebe]

I'm someone who is pretty skilled with electronics. I've been soldering and making or modifying electronic things for years now, and I know what I'm doing. I chose to buy my own battery pack because I didn't like the risk involved with DIYing it. Yeah, it cost me a lot more, but I knew the pack was made correctly. If you choose to undertake this, be sure you know what you're doing, know all the pros/cons and do it at your own risk, that's all I have to say.

PS: Can't we all just get along?

 

[mikey]

Why not just build this to go with em....

Home made spot welder, complete with 2x4 handle.

 

[Maviryk]

Why not just build this to go with em....

Home made spot welder, complete with 2x4 handle.

LOL. I think you might just blow up the battery with that. You want much lower current and the ability to control the duty cycle.

There's a bunch of tutorials on DIY CD battery tab welders online, but they're not very reliable for long term use, especially with cheap capacitors and power supplies. (Power supplies can't put out enough current, capacitors explode from too much voltage)

You'll have to be able to control your voltage, current, and duty cycle. Too much current you'll blow out the metal, too little and you won't get a good weld.

I designed my own dual pulse welder using laboratory grade power supplies and computer grade capacitors.

Here's an example of a DIY CD Battery tab welder:

 

[Stephen_ver4.0]

Thanks for the reps fellas. I hope you get a kick out of the inexpensive project.

 

[Noah]

some goodies to add

One of the A123 cells in the last batch I bought was defective.
Got very hot while charging 57 degrees C and wouldnt hold a charge.
SOOOO i took it apart....
Its pretty simple in there.
What interested me the most was the cross section of the negative end plate and what effects applying pressure to it would have. Which is what happens when I clamp the cells in between the nylon plates.
The end plate comes almost to the center and a narrow rivet goes through the terminal and inside to the copper strip. The terminal is insulated from the end plate by a plastic material.

 

[Noah]

Wonder if flint could whip some of these up?

Good to see your thread going well SSS
Heres a new concept for A123 cells
Solderless framing. Just started a 09R1 engine with this battery.
Theres no solder or paste between the cells and connector plates
heres the design process
3d modelling Inventor

Inventor drawing which makes DXF files

AutoCAD which doctors the DXF file so the tool path progy can use it

Tool path progy (comes with router) to program contours and depth of cut.

3D visualization of the cut.

And watch the chips fly
http://www.youtube.com/watch?v=OEHEmlBgBM4

 

[SEBSPEED]

^^^Now that's fuckin cool!

 

[Phoebe]

What Noah posted is definitely a safer way to DIY these packs.

 

[SEBSPEED]

Not really building as much as it is assembling though. Unless you do the machining yourself.

 

[Phoebe]

Not really building as much as it is assembling though. Unless you do the machining yourself.

Who cares? I don't build my own carb floats or headlight bulbs either! Get what I'm saying?

 

[brockzila]

^^^Now that's fuckin cool!

yes you correct that is fucken cool

 

[Noah]

easier to rebuild it later too
Most of us will have our bikes till we are so old we cant throw a leg over..

might be a good investment

 

[mikey]

That's what I was asking about! That way if one of the batteries goes south, you can swap it out. FYI, a small diode-isolated LED indicator could show if the battery was good or bad.

 

[Noah]

someone send that cad to flint and see what these are gonna cost us

edit..just pm'ed him

 

[mikey]

I'd kick in for one. I'm not feeling the bolts to connect it together. I'd rather see those counter-sunk.


EDIT - I'd want a 6-slot though.

 

[1st bel air fighter]

i clicked on this thread and started reading the end and wanted to know what all the fighting was about so i read through the whole thing.

first, mad props for the DIY great write up for us on a budget life style do-it urselfers

sec, mavrik (or how ever u spell it) dont be such a money hungry butt hurt (cuz he showed everyone how easy it is to make) dickhead. this is what this site is here for should all the mechanic get all bent out of shape cuz someone did a DIY on adjusting carbs or a fabricator sue someone cuz they did a DIY on SSSA swap. jeez man not everything in life is about trying to ring ur friends dry DONT BE SUCH AN ASSHOLE

 

[mikey]

i clicked on this thread and started reading the end and wanted to know what all the fighting was about so i read through the whole thing.

first, mad props for the DIY great write up for us on a budget life style do-it urselfers

sec, mavrik (or how ever u spell it) dont be such a money hungry butt hurt (cuz he showed everyone how easy it is to make) dickhead. this is what this site is here for should all the mechanic get all bent out of shape cuz someone did a DIY on adjusting carbs or a fabricator sue someone cuz they did a DIY on SSSA swap. jeez man not everything in life is about trying to ring ur friends dry DONT BE SUCH AN ASSHOLE

While he did get a little enthusiastic, pointing out the safety ssue of covering the releif valve was a stand up thing to do. He could have sat back, let him make something that was possibly dangerous, and done nothing. He opened his mouth and pointed out a safety issue.