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eastern57
11-10-2009, 07:37 PM
Don't remember if I posted this here... well here it is anyway ;)

This is how I make [most of] my Li-Ion packs. I get the ones that are already protected, so they're easy to deal with.

These are Ultrafire 18500 (18mm x 50mm) with the integrated protection circuit. And I solder them directly. No problems (yet, of course).

http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05123.jpg


First, these have a little coating (silicon, I think) on the positive knobs, you'll have to sand this coating off otherwise the solder will roll right off. It's kind of hard to tell, but these have been sanded down... might be able to see the marks...

http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05124.jpg


With a hot iron, melt a little drop on the knob. Hold it for just a second or two so the battery tip can heat up and grab the solder. Do this for the positive poles one each cell. *The negative sides don't require sanding, but be careful not to hold it for more than a split-second... you'll see that it flows right on.

http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05125.jpg


For the connection between the batteries, I use a little scrap of 22g to bridge the two.

http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05126.jpg
http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05127.jpg
http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05130.jpg


And some leads for the ends as well.

http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05128.jpg


Lastly, it all gets heat shrunk'ded together.

http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05133.jpg

A few tips:
- Make sure your iron is ready to go (I use a 30w radio shack - works great for my purposes), and rosin core solder makes it easier too

- The wrapping around the battery is heat sensitive -shrink tubing- so if you heat the negative pole too long, you'll see the edges of the wrapping receed

- This is for PROTECTED CELLS ONLY!!!

- I highly recommend that you use a recharge port of some type with this set-up

- Funny thing about those protection circuits: they cut power off entirely when they deplete to a certain level - so don't freak out when your saber shuts off without warning... just plug it back in!

Good luck!



eastern57 ;)

Rhyen Skytracker
11-10-2009, 08:08 PM
Great tutorial eastern. Thanks.

cardcollector
11-10-2009, 08:42 PM
Thanks a lot! you did a great job!:cool:

Thaxos
11-10-2009, 08:53 PM
Great job, but it sure isn't silicon. That would be non-conductive, and thus be counter intuitive for a battery.

Matt Thorn
11-11-2009, 05:06 AM
Great tutorial. I was about to add that 1) you can make the pack with the batteries side-by-side rather than end-to-end, and 2) that the low mAh (900) of the 14500s limits the LEDs they can be used with...

...and then I reread your post and realized you are using the 18500s. :oops:

As Emily Litella would say, "Nevermind." ;)

I haven't worked with the 18500s: only the 14500s and bulky 18650s. Looking at your post and noticing that the 18500s put out 1600 mAh, it occurred to me that they would be perfect for a project I am working on. Last night I made a butt-ugly pack from six AAA Ni-MHs, but the heatshrink keeps it from fitting into my MHS hilt. I think I'll get me a couple of those 18500s and make a pack exactly like yours. What size heatshrink did you use?

Rhyen Skytracker
11-11-2009, 05:25 AM
Last night I made a butt-ugly pack from six AAA Ni-MHs, but the heatshrink keeps it from fitting into my MHS hilt.

Matt, I made a pack from 6 AAA Ni-MH batteriesw and they fit just fine in a MHS hilt. Look at post number 6 in this thread: http://forums.thecustomsabershop.com/showthread.php?t=9386

Matt Thorn
11-11-2009, 05:42 AM
Matt, I made a pack from 6 AAA Ni-MH batteriesw and they fit just fine in a MHS hilt. Look at post number 6 in this thread: http://forums.thecustomsabershop.com/showthread.php?t=9386
Thanks, Rhyen. Yeah, I had thought about end-on-end, but was too clever by half and decided to make it into a "roll." That would work fine if I was using seven AAAs and extremely thin heatshrink, but, well, as you can see my little Frankenstein's monster did not turn out quite as well as I had hoped. BTW, that's hot glue on the ends, not "abstract expressionist soldering." ;)
http://lh6.ggpht.com/_THBqz9vPciU/SvqvXY0O-RI/AAAAAAAACMs/iC3MxEAXmVM/s400/IMG_1324.jpg (http://picasaweb.google.com/lh/photo/KSA9dJv46rJpLZiWIlZDzA?feat=embedwebsite)
http://lh6.ggpht.com/_THBqz9vPciU/SvqvYbR6UEI/AAAAAAAACMw/t_KEMus6oHs/s400/IMG_1325.jpg (http://picasaweb.google.com/lh/photo/nPeVCIDstln2W9gCi3LkQQ?feat=embedwebsite)

eastern57
11-11-2009, 10:06 AM
... the low mAh (900) of the 14500s limits the LEDs they can be used with...


No, it doesn't. "h" = hours... Not the same as current output. The only thing that's "restricted" is runtime.

"Miles are NOT the same thing as Miles Per Hour..."
- Novastar

;)

Matt Thorn
11-11-2009, 09:19 PM
No, it doesn't. "h" = hours... Not the same as current output. The only thing that's "restricted" is runtime.

"Miles are NOT the same thing as Miles Per Hour..."
- Novastar

;)
You're right, of course. My bad. Just forgot my ABCs there. Must be early-onset Alzheimers. :oops:

xl97
11-12-2009, 08:30 AM
One of my favorite tuts.

good job, Big Ez. :)

Novastar
11-12-2009, 09:33 AM
Great explanations, Eastern. And lol @ the Nova-quote, hahahh. It seems we're running into this a lot lately--the whole "debacle" of mA vs. mAh. Oh well. In perspective, I certainly did not understand this for a LONG time until Corbin explained it to me back in 2005. You can hardly expect people with ZERO electronics experience to understand quickly though... so... if anyone understands... I do. :D

One other note...

I have been told by someone who is pretty darn "expert" in the Li-Ion industry that using individually protected cells (keyword: individually...) to make 7.4v packs or 11.1v or whatever... can lead to long-term problems.

Now... I have NEVER seen an issue with this as of yet--even though I don't make 7.4v packs with individually (keyword: individually...) protected cells. But I see them being used ALL the time (Yoda does so with his Graflex Chassis setups, and many many folks use the 2 x 14500 "AA"-style cells in little AA spring packs, which are wired up for the voltage).

I'm not sure what that means, since... it's obviously conflicting with the guy I know (who works for a very well-known high tech company which I cannot say).

Additionally, it's also fairly common thought that cells that go into packs are supposed to be metered/tested in ways that show they should go together. What do I mean? Well, I mean to say--like LEDs and "binning"... no two are created totally identical. Some are closer together as "matches" than others. In this case--the cell chemistry, inherent resistance, discharge rates, TRUE capacity (down to the last little bit)... is supposed to match darn well.

Unfortunately, you can't really determine this on your own when you have two cells in front of you. Hopefully those cells are from the same company, bought at the same time... and GOD FORBID you buy 2 cells from differing companies at differing times with differing mAh capacities... and then throw a 7.4v PCB on them and call it good!! O.O This could be dangerous... or simply just cause problems later on.

Again, I don't know what the long-term effects of putting together "pre-protected 3.7v" cells... but I figured I should just say... mise en garde. :)

BOTTOM LINE = It's a good standard practice for building Li-Ion packs to use (initially) unprotected cells... and then throw on the correct PCB for 7.4v, 11.1, 14.4, blah blah blah... and don't mix brand types, nor "mAh" types... and don't use one cell you got in 2006 and one from 2009. :D I know, it's pretty obvious. heheh

LINK TO VIDEO TUTORIAL (7:24):
Although it's near the end of the video (7:24)... .... --> http://www.youtube.com/watch?v=DNcc2oZWmO8

:)

Matt Thorn
11-12-2009, 07:19 PM
Great information, Novastar. Thanks. I had wondered vaguely about the PCBs for Li-Ion packs (e.g., Why are unprotected Li-Ion batteries sold at all? Why are 7.2V PCBs sold separately?). Maybe one of our electronics pros (Erv? Eandori?) can shed some more light on the issue.

And if my record with wrapping my head around the "mA ≠ mAh" concept is any indication, I may actually be able to grasp the Li-Ion PCB issue in roughly two years. :rolleyes:

Jay-gon Jinn
11-12-2009, 07:24 PM
Great information, Novastar. Thanks. I had wondered vaguely about the PCBs for Li-Ion packs (e.g., Why are unprotected Li-Ion batteries sold at all? Why are 7.2V PCBs sold separately?). Maybe one of our electronics pros (Erv? Eandori?) can shed some more light on the issue.

And if my record with wrapping my head around the "mA ≠ mAh" concept is any indication, I may actually be able to grasp the Li-Ion PCB issue in roughly two years. :rolleyes:
Unprotected cells are sold so that a hobbyist can make a custom pack to suit their individual needs. You just need to make sure that when you add a pcb to your custom pack made with un-protected cells that it matches the pack you've made.

Maurnick
12-03-2009, 09:23 PM
How could one recharge a pack like this if it weren't being set up in-hilt with a recharge port?

Shadar Al'Niende
12-03-2009, 11:05 PM
How could one recharge a pack like this if it weren't being set up in-hilt with a recharge port?

you wouldn't?


seriously though, You would have to do some dangerous wiring...

Matt Thorn
12-03-2009, 11:50 PM
Yeah, a charge port is pretty much a must.

eastern57
12-04-2009, 06:06 PM
no there are ways. You can put a quick disconnet on your battery, and another on an adaptor for the charger, you can do it that way. Buy two QDs: one set for the saber guts to the battery pack and an extra connection for a charger adaptor.

You will have to cannabalize one of the charger adaptors, but it's an option... I've done it before.

Matt Thorn
12-04-2009, 06:16 PM
no there are ways. You can put a quick disconnet on your battery, and another on an adaptor for the charger, you can do it that way. Buy two QDs: one set for the saber guts to the battery pack and an extra connection for a charger adaptor.

You will have to cannabalize one of the charger adaptors, but it's an option... I've done it before.
I did think about that possibility before responding, but I couldn't imagine a scenario in which that would actually be preferable. Another possibility, if you really don't want to have a charge port visible on your hilt, is to hide the port inside the pommel, and pull it out for recharging. I'm pretty sure I've seen photos of just this sort of set-up. Either way, you would still need a Tenergy-style smart charger.

Lan-Ja Hamil
12-04-2009, 08:04 PM
I did think about that possibility before responding, but I couldn't imagine a scenario in which that would actually be preferable. Another possibility, if you really don't want to have a charge port visible on your hilt, is to hide the port inside the pommel, and pull it out for recharging. I'm pretty sure I've seen photos of just this sort of set-up. Either way, you would still need a Tenergy-style smart charger.

I saw in one of Novastars videos he hides the recharge port inside the pommel of the saber. Just unscrew the pommel and there it is.

eastern57
12-04-2009, 08:22 PM
I did think about that possibility before responding, but I couldn't imagine a scenario in which that would actually be preferable. Another possibility, if you really don't want to have a charge port visible on your hilt, is to hide the port inside the pommel, and pull it out for recharging. I'm pretty sure I've seen photos of just this sort of set-up. Either way, you would still need a Tenergy-style smart charger.

If you have an Ultrasound or a CF - where there's battery draw, even while the saber is off - you'll need some method to cut battery power entirely. A recharge port does that... or just a separate power switch.

I use a battery/QD on the this set-up, because I had wired in a separate power switch, and a recharge port wasn't necessary.

http://forums.thecustomsabershop.com/showthread.php?t=8948

cardcollector
12-05-2009, 09:45 AM
Just so everyone knows...

These are the size of a shotgun shell!

Strydur
12-05-2009, 11:12 AM
What are the size of a shotgun shell? Not the ones we sell. Maybe I missed something.

A lot of devices have a power draw when off but its so small you would never notice it. For instance our new LED driver combo we will have soon that adds the 3w driver functions to the adjustable driver uses only 50 microamps while in standby which is 0.00005 of a amp so it would take a long time to drain your batteries down.

Shadar Al'Niende
12-05-2009, 11:37 AM
Think he is referring to the 18500's in the OP...

cardcollector
12-05-2009, 12:20 PM
Yeah, these...

http://i306.photobucket.com/albums/nn260/eastern57/MHS%20hilt%206/DSC05123.jpg

about a 22 size.

Shadar Al'Niende
12-05-2009, 12:41 PM
intel on the inch'age of two side by side? *hopes*


or is that what you meant by 22? :confused:

Rhyen Skytracker
12-05-2009, 01:19 PM
The 18500s are too large to fit side by side in a MHS hilt.

cardcollector
12-05-2009, 01:22 PM
http://www.leelofland.com/wordpress/wp-content/uploads/2008/05/handgun_rounds1.jpg
you could easily insert the trustfire 18500 in place of the shotgun cartridge...

I was trying to compare it to a common object... I guess Rhyen and i and the only ones who use shotguns...:rolleyes:;):p

eastern57
12-05-2009, 02:25 PM
18500 refers to the size: 18mm x 50mm.

14500 = 14mm x 50mm.

18650 = 18mm x 65mm...

Shadar Al'Niende
12-05-2009, 02:59 PM
18500 refers to the size: 18mm x 50mm.

14500 = 14mm x 50mm.

18650 = 18mm x 65mm...

holy crap! That is WAY cool! :cool:

So since an MHS ID is 1.25" or 31.75mm ('ish) making a pack and allowing for room, (1.75mm's worth) that would mean anything more than a 15000 wouldn't fit side by side...so 14500's are our best bet....

ITS A PERFECT SYSTEM I TELL YOU!!! PERFECT!!!

Jedi-Loreen
12-05-2009, 11:35 PM
You don't know much about real fire arms, do you, cc? :p A .22 bullet is less than a 1/4".

You were closer when you said shotgun shell. A 12 gauge shell is 18.572mm in diameter. ;)

cardcollector
12-06-2009, 07:51 AM
aaaaah, I knew that wasn't right!:(

Thanks J-lo... I had a brain freeze for some reason...
Maybe its this darn english comp test I'm studying for...

xl97
12-15-2009, 10:38 AM
whoever caught it...nice job! :)

Shadar Al'Niende
12-15-2009, 10:39 AM
amen...

Jedi-Loreen
12-15-2009, 10:41 AM
That would be me that got it. Sorry I didn't catch it sooner. I'd hoped I'd got it before anyone else saw it. At least it was on there for a few minutes.

Shadar Al'Niende
12-15-2009, 10:42 AM
Only saw it due to email notification, by the time i clicked the link to get into the thread it was gone, figured it was spam or some such unsavory items ;)

LIGHTNING FAST J-LO!!! :cool:

vamphunterx
01-31-2010, 07:50 PM
Thank you for posting this tutorial

eastern57
02-01-2010, 09:58 AM
you're welcome ;)

Causa
05-11-2010, 03:47 PM
Here is a picture of a wiring diagram for these 18500's with an external PCB.

Thanks for Sunrider for a 3 day long, 23 email exchange helping me with this. He answered ALL of my questions and now I can safely and confidently build this pack.

That is a 4.2amp polyswitch between the two cells, and a 5 amp, 7.4v, 2 cell PCB.