Low-power no-solder idea...

Batteries, Chargers, and Battery Management Systems.
User avatar
cal3thousand   1.21 GW

1.21 GW
Posts: 3603
Joined: Mar 26 2012 4:47pm
Location: California

Re: Low-power no-solder idea...

Post by cal3thousand » May 13 2014 11:02am

So what we need is a low temp solder to be made. Maybe graphene paste in the future?
Get a Cycle Analyst and a Multimeter, you're still a noob if you don't have at least one of each.

Planning on posting questions or buying anything on this site? Put up your country (at minimum) on your profile. This is a worldwide forum and we haven't reached clairvoyance.

Punx0r   100 GW

100 GW
Posts: 5178
Joined: May 03 2012 8:16am
Location: England

Re: Low-power no-solder idea...

Post by Punx0r » May 13 2014 3:20pm

At least it has been established just how bad a spring connection can be :shock:

There are some very low melting-point metal alloys, but I don't know if they will stick to other metals.

Hillhater   100 GW

100 GW
Posts: 9931
Joined: Aug 03 2010 10:33pm
Location: Sydney ..(Hilly part !) .. Australia/ Down under !

Re: SPRING TEST

Post by Hillhater » May 13 2014 6:44pm

Matt Gruber wrote:i tested a spring from a flashlight!
at 2.5A 208 mv drop! (remember my epoxy copper is 6 mv)
at 7 amps 608 mv drop and it burned my finger! (coppery/epoxy 12 mv)
i had this spring lying around because i soldered the wires last year direct to the cell, and put in a real switch and took out the spring. flashlight works perfect ever since. no flickers ever. next flashlight i'll use epoxy.

Matt, it has been said many times before,..you dont use the spring as the conductor, only to apply pressure to the contacts..like the way springs on a motor commutator work... or the way a rubber "spring" was used to apply pressure for the pack snath built here...
http://endless-sphere.com/forums/viewto ... 14&t=57810

If you are serious about cold contact systems, i suggest you redo your tests using a separate contact/conductor with the spring to just apply the pressure....then let us know what the volt drop is.
This forum owes its existence to Justin of ebikes.ca

User avatar
TheBeastie   1 MW

1 MW
Posts: 1829
Joined: Jul 28 2012 12:31am
Location: Melbourne Australia

Re: SPRING TEST

Post by TheBeastie » May 13 2014 9:39pm

Matt Gruber wrote:i tested a spring from a flashlight!
at 2.5A 208 mv drop! (remember my epoxy copper is 6 mv)
at 7 amps 608 mv drop and it burned my finger! (coppery/epoxy 12 mv)
i had this spring lying around because i soldered the wires last year direct to the cell, and put in a real switch and took out the spring. flashlight works perfect ever since. no flickers ever. next flashlight i'll use epoxy.
So sounds like that epoxy is pretty good compared to spring, do you have a URL for it?
Thanks.
Speed Kills Range, 10mph = 46 miles range, 20mph = 20 miles, 30mph = 8 miles rangehttps://goo.gl/1JNL53
Over Charging Kills ur battery bit.ly/1hzWKl4
Consider PAS as your only throttle https://goo.gl/Kg1F8F
Fuel-Cell is the ultimate battery coupled with 4th-gen Nuclear
https://goo.gl/TcKtHs https://goo.gl/ZhFFot https://goo.gl/gfa215
10 Square Miles of solar panels = 0.12GW average power! https://goo.gl/Ub1S39

User avatar
amberwolf   100 GW

100 GW
Posts: 27217
Joined: Aug 17 2009 6:43am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Low-power no-solder idea...

Post by amberwolf » May 13 2014 11:20pm

docnjoj wrote:I have no idea about an epoxy connection but most brushed electric motors use a spring and a copper braid and motors carry a lot of current.
In that application, hte braid is the current-carrying path, not hte spring, htough. The braid is typically embedded in hte carbon brush's core, and simply fed thru the center of the spring that pushes the brush down onto the commutator. The other end of the braid is often bradded/riveted to a connector for the actual power wire to the motor brushes, sometimes it is soldered or crimped directly to that wire.


Even so, because of the arcing across commutator/brushes, the springs often see a lot of heat--but that heat isn't because of anyting the spring does, electrically (as the spring isn't part of the circuit, as it would be in hte proposed battery pack).

Matt Gruber   1 MW

1 MW
Posts: 1626
Joined: Feb 08 2007 11:02am
Location: New Smyrna Beach FL

Re: SPRING TEST

Post by Matt Gruber » May 14 2014 3:56am

Hillhater wrote:
Matt Gruber wrote:i tested a spring from a flashlight!
at 2.5A 208 mv drop! (remember my epoxy copper is 6 mv)
at 7 amps 608 mv drop and it burned my finger! (coppery/epoxy 12 mv)
i had this spring lying around because i soldered the wires last year direct to the cell, and put in a real switch and took out the spring. flashlight works perfect ever since. no flickers ever. next flashlight i'll use epoxy.

Matt, it has been said many times before,..you dont use the spring as the conductor, only to apply pressure to the contacts..like the way springs on a motor commutator work... or the way a rubber "spring" was used to apply pressure for the pack snath built here...
http://endless-sphere.com/forums/viewto ... 14&t=57810

If you are serious about cold contact systems, i suggest you redo your tests using a separate contact/conductor with the spring to just apply the pressure....then let us know what the volt drop is.
as i've said many times before, at the beach salt air corrodes everything, even remote controls in the house! So i can't use any contacts exposed to the air. By covering and sealing the contact area with JB WELD i hope to eliminate or delay for years corrosion. and as i said before, i've ordered a cell holder with spring to use as a jig to apply pressure TO A COPPER WIRE while the JB sets. once the joint is "shrink wrapped" in JB the spring is REMOVED and the cell is installed. i tested a spring because some people like flashlight springs, and didn't know how to test it. i rip them out because they are so bad.
.
i get JB WELD at wal-mart. the slow cure type, about $5.
on ebay it costs more, so maybe the price went up?

User avatar
dogman dan   100 GW

100 GW
Posts: 34929
Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: Low-power no-solder idea...

Post by dogman dan » May 14 2014 6:25am

I get it. That could work. Especially for 1c type loads or less. Or you could use a furniture clamp, or other method of applying the pressure. JB weld can be amazingly strong in some applications. Still just a pressure connection, but with lower resistance copper hopefully doing a decent contact.

Interesting idea. Of course if you had a spot welder, like the factories in china, you'd just use that. I'll be very interested to see how this experiment turns out.

Just had a thought. Doesn't JB weld have metal in it? Maybe not. If it conducts, can't cover the can much on the + side. It won't stick so great to the plastic shrink cover. You might look at marine grade PC7. Very slow cure, and high temp.

Matt Gruber   1 MW

1 MW
Posts: 1626
Joined: Feb 08 2007 11:02am
Location: New Smyrna Beach FL

Re: Low-power no-solder idea...

Post by Matt Gruber » May 14 2014 8:30am

my meter says jb has infinite ohms.
as for 1c, what fun is that? :lol: sony VTC4 or sony VTC5 30amp, 60 amp peak 2-2.5ah. i would test at 15amp as my scooter peaks at 15. if it works i can run 10s1p since last time at the car show it only used 0.9ah.
todays test 2 ring connectors, 1 is tinned copper, the other cheap thin aluminum. just experimenting on old dead cells. i was fixing my scooter and had a little JB left over. the hole in the center isn't ideal, but they were available in quantity :lol:
Looks like i'd do this in 2 stages.
1st epoxy connector with little JB.
test it. if it passes the v drop, slather on plenty of JB to insulate, and make a STRONG joint that won't come apart. If the connection gets worse over the long term, it will probably heat up and melt the JB just enough to kill power, alerting me that a repair is needed. that's just a guess as JB doesn't melt easily, they say 400F+ i think. it works on car radiators so it can take some heat.
Last edited by Matt Gruber on May 20 2014 3:32pm, edited 1 time in total.

Matt Gruber   1 MW

1 MW
Posts: 1626
Joined: Feb 08 2007 11:02am
Location: New Smyrna Beach FL

Re: Low-power no-solder idea...

Post by Matt Gruber » May 14 2014 10:54am

so yesterday i charged one of these dead, 0v cells, before , it would go dead in 1 day. today it held the 4.06!
so why not do a discharge test thru the epoxy connection? BUT i was careless when i set it down, and the wires shorted :roll:
before i knew it there was a puff of smoke and one JB wire fell off! WOW this is FANTASTIC since it fell off before the built in thermal fuse could react! it got very warm, i'd guess 110-115F, there was a lot of amps flowing for about 3 seconds.
so the cell can be used for more LIVE experiments. it still has 4.02v. i used a razor blade to scrape off the JB.
SO THE JB WELD ACTS AS A FUSE! THIS IS GREAT! Like a dream come true!
for those that don't know, i'm using sony US18650V from makita packs. Once the thermal fuse blows, it can't be changed and the cell is trash.

User avatar
cal3thousand   1.21 GW

1.21 GW
Posts: 3603
Joined: Mar 26 2012 4:47pm
Location: California

Re: Low-power no-solder idea...

Post by cal3thousand » May 14 2014 11:20am

Pictures? :D
Get a Cycle Analyst and a Multimeter, you're still a noob if you don't have at least one of each.

Planning on posting questions or buying anything on this site? Put up your country (at minimum) on your profile. This is a worldwide forum and we haven't reached clairvoyance.

User avatar
marty   10 MW

10 MW
Posts: 2190
Joined: Apr 19 2007 5:44pm
Location: Buffalo, New York USA
Contact:

Re: Low-power no-solder idea...

Post by marty » May 14 2014 2:08pm

http://endless-sphere.com/forums/viewto ... ry#p758973
Doctorbass wrote:2009-2010-2011 ZERO MOTORCYCLES BATTERY ASSEMBLY METHOD:

One great and ingenious method that already was in use by zero motorcycle is to use copper braided strap with rubber ring to hold them on the top of neg and po of the cells! Then you can add a heatshrink to add pressure and avoid rubber to move.

Easy, cheap and easy to repair your pack.

for the rubber they used some bicycle tire rubber tube sliced to form some ring ! the advantage is that these rubber do not dry very fast and they are not too affected by moisture or temperature so they sustain pressure between the copper braided strap and cell tab very well!

Here is couples of pictures i took when i had to do some maintnance on a ZERO battery for a friend of mine. This battery was made to take 300A burst and i s a12P config meaning about 25A per cell tab and only holded by a rubber tensil pressure!
Please note that these are 26700 cells and each cylinder is in fact 2s1p ( 7.4V):

Doc
Image
Image
Image
Image
Image
MARTY
Volt Electric Vehicles
http://www.voltev.com

User avatar
cal3thousand   1.21 GW

1.21 GW
Posts: 3603
Joined: Mar 26 2012 4:47pm
Location: California

Re: Low-power no-solder idea...

Post by cal3thousand » May 14 2014 2:24pm

^ Some one is selling those very modules in the Market section right now :mrgreen:
Get a Cycle Analyst and a Multimeter, you're still a noob if you don't have at least one of each.

Planning on posting questions or buying anything on this site? Put up your country (at minimum) on your profile. This is a worldwide forum and we haven't reached clairvoyance.

User avatar
dogman dan   100 GW

100 GW
Posts: 34929
Joined: May 17 2008 12:53pm
Location: Las Cruces New Mexico USA

Re: Low-power no-solder idea...

Post by dogman dan » May 14 2014 6:02pm

Interesting idea. Cut up road bike tube for 18650's?

Matt Gruber   1 MW

1 MW
Posts: 1626
Joined: Feb 08 2007 11:02am
Location: New Smyrna Beach FL

Re: Low-power no-solder idea...

Post by Matt Gruber » May 15 2014 7:53am

JB changes the game for me. Now i can run any high power cell(not just Konions) and have a cheap effective external fuse, that happens to hold the wire firmly against the cell. And insulate the pack to prevent shorts. Those bare packs you guys are so proud of look scary to me.
My packs are small, so i dont mind the overnight set time. JB does sell a quick set epoxy for those in a hurry.
I tested some 15a fuses and the v drop was 70 mv on the best ones. others, the rejects were 90-110 mv.(at 15 amps)
I'm going to predict that it will be a long time until this catches on, like on that video where a guy could not make jb conduct to save his life. too dim witted to apply pressure to make a good connection :lol:
For now, i have an EXCLUSIVE method.

Matt Gruber   1 MW

1 MW
Posts: 1626
Joined: Feb 08 2007 11:02am
Location: New Smyrna Beach FL

Re: Low-power no-solder idea...

Post by Matt Gruber » May 18 2014 4:18pm

So i made up a wood holder and used a block of wood against the cell, and a spring to maintain pressure as it cured, 3 cells on this test, all working, 2 from the dead pile but now holding a charge.
good thing i used a red wire on the + because both ends looked the same, solid JB. very hard to find any bare area to measure the v drop...
so i cut a tiny spot, and they were all 4 -5 mv!
JB gives short protection as the JB wants to cover and insulate anything not pressed tight.
this is about 3C discharge, so no mercy. they got warm in 2 minutes, but the connections stayed either the same or maybe not as warm.
Will test again before i buy any cells without tabs. No bare copper on these, only factory tinned wire, so they should conduct excellent for years, I hope.
For now i'm testing in my -9 scooter. Gave it 5 seconds WOT for 5c and none of the fuses blew. Will not be doing this again, 3-4c is normal pulling away from a stop. That is plenty for 2011 sony konions. They are past their prime years. Due for old age home soon :lol: :lol:
Last edited by Matt Gruber on May 20 2014 9:28am, edited 2 times in total.
Converted window AC's to central system.
Reversed type 2 diabetes and hyperthyroid by limiting calories from fat to 7%. Thanks to Dr Mcdougall, Dr Esselstyn, Dr Barnard, Dr Greger, Dr Ornish and Nathan Pritikin. (all on YouTube)
Favorite foods: corn, potatoes, sweet potatoes, onions, cabbage, broccoli, lintels, black beans, mushrooms, cherries, mangoes, bananas, pineapples, blueberries, strawberries, pasta, home made rolls and no-fat chips.

User avatar
TheBeastie   1 MW

1 MW
Posts: 1829
Joined: Jul 28 2012 12:31am
Location: Melbourne Australia

Re: Low-power no-solder idea...

Post by TheBeastie » May 18 2014 9:29pm

Matt Gruber wrote: i thinking of buying a CLOSE UP camera- any low price models u guys can recommend? I'd like you to see this JB up close.
You can try a macro lens for a camera phone from eBay http://www.ebay.com.au/sch/i.html?_trks ... o&_udhi=16
Or what about a USB microscope are pretty cheap, most don't have stands that don't get in the way.

http://www.ebay.com/sch/i.html?_trksid= ... &_from=R40
Speed Kills Range, 10mph = 46 miles range, 20mph = 20 miles, 30mph = 8 miles rangehttps://goo.gl/1JNL53
Over Charging Kills ur battery bit.ly/1hzWKl4
Consider PAS as your only throttle https://goo.gl/Kg1F8F
Fuel-Cell is the ultimate battery coupled with 4th-gen Nuclear
https://goo.gl/TcKtHs https://goo.gl/ZhFFot https://goo.gl/gfa215
10 Square Miles of solar panels = 0.12GW average power! https://goo.gl/Ub1S39

kiwipete   100 mW

100 mW
Posts: 45
Joined: Nov 13 2013 9:40pm

Re: Low-power no-solder idea...

Post by kiwipete » May 19 2014 9:13pm

Or this: turn your smart phone into a microscope: http://www.instructables.com/id/10-Smar ... onversion/

User avatar
liveforphysics   100 GW

100 GW
Posts: 14134
Joined: Oct 29 2008 1:48am
Location: Santa Cruz, CA, USA

Re: Low-power no-solder idea...

Post by liveforphysics » May 20 2014 1:26am

No solder is the only way a pack can be manufactured and have acceptable cell failure rates for any lithium ion cell IMHO.

If you are getting the electrolyte above 120degC you are decomposing it as well as causing initiation points for other latent failure modes from solvent decomposition by-products that are now contaminating the cell.

I no longer consider it a pack construction topology I could recommend for any application.

Some guy on here has a brilliant easy DIY dimpled copper strip and the precisely critical low-compression-set foam that serves the function of the spring coil in your arrangement. A fat copper strip is multiple orders of magnitude less R than a coil of any of the springy metals.
Each carcinogen vapor exposure includes a dice roll for cancer.

Each mutagen vapor exposure includes a dice roll for reproductive genetic defects in your children.

Each engine start sprays them into a shared atmosphere which includes beings not offered an opportunity to consent accepting these cancer experiences and defective genetics life experiences.

Every post is a free gift to the collective of minds composing the living bleeding edge of LEV development on our spaceship.

cwah   10 GW

10 GW
Posts: 4173
Joined: Jul 24 2011 5:42am
Location: Between paris and london

Re: Low-power no-solder idea...

Post by cwah » May 20 2014 3:34am

liveforphysics wrote:No solder is the only way a pack can be manufactured and have acceptable cell failure rates for any lithium ion cell IMHO.

If you are getting the electrolyte above 120degC you are decomposing it as well as causing initiation points for other latent failure modes from solvent decomposition by-products that are now contaminating the cell.

I no longer consider it a pack construction topology I could recommend for any application.

Some guy on here has a brilliant easy DIY dimpled copper strip and the precisely critical low-compression-set foam that serves the function of the spring coil in your arrangement. A fat copper strip is multiple orders of magnitude less R than a coil of any of the springy metals.
Even spot welding is non acceptable? but so many factories are doing that. Are they all wrong?
Help me find my stolen electric brompton: http://bit.ly/1a0vbBC and Bosch Sinus B3 http://bit.ly/1eV0WQz

User avatar
cal3thousand   1.21 GW

1.21 GW
Posts: 3603
Joined: Mar 26 2012 4:47pm
Location: California

Re: Low-power no-solder idea...

Post by cal3thousand » May 20 2014 10:53am

cwah wrote:
liveforphysics wrote:No solder is the only way a pack can be manufactured and have acceptable cell failure rates for any lithium ion cell IMHO.

If you are getting the electrolyte above 120degC you are decomposing it as well as causing initiation points for other latent failure modes from solvent decomposition by-products that are now contaminating the cell.

I no longer consider it a pack construction topology I could recommend for any application.

Some guy on here has a brilliant easy DIY dimpled copper strip and the precisely critical low-compression-set foam that serves the function of the spring coil in your arrangement. A fat copper strip is multiple orders of magnitude less R than a coil of any of the springy metals.
Even spot welding is non acceptable? but so many factories are doing that. Are they all wrong?
He is mentioning SOLDER. Much different process than spot welding. Spot welding uses a high current impulse to create a small weld. It's so fast that the heat build-up is minimal. Compare that to solder, which requires a certain melting temperature for solder to flow, and holds the heat on the joint for much longer.
Get a Cycle Analyst and a Multimeter, you're still a noob if you don't have at least one of each.

Planning on posting questions or buying anything on this site? Put up your country (at minimum) on your profile. This is a worldwide forum and we haven't reached clairvoyance.

dnmun   100 GW

100 GW
Posts: 16190
Joined: Jun 09 2008 1:32pm
Location: portland, or and loveland, co

Re: Low-power no-solder idea...

Post by dnmun » May 20 2014 2:15pm

JB Weld does have metal in it. a fine powdered form of highly magnetic iron is incorporated into the resin. that is part of the reason it is used to repair metal fatigue cracks or cracked water jackets on engine block.

User avatar
parabellum   10 MW

10 MW
Posts: 2067
Joined: Nov 19 2010 9:55am
Location: Dominican Republic, north.

Re: Low-power no-solder idea...

Post by parabellum » May 20 2014 10:24pm

dnmun wrote:JB Weld does have metal in it. a fine powdered form of highly magnetic iron is incorporated into the resin. that is part of the reason it is used to repair metal fatigue cracks or cracked water jackets on engine block.
And It is the reason why JB weld desapears in the gap right away when you glue neodymium magnet to iron core. :D

Matt Gruber   1 MW

1 MW
Posts: 1626
Joined: Feb 08 2007 11:02am
Location: New Smyrna Beach FL

Re: Low-power no-solder idea...

Post by Matt Gruber » May 31 2014 10:43am

so i got my $1 18650 single cell holder. not worth $1 imo, but i see where a guy got 50 for $20.
easy to upgrade. there is a rivet on each end with a hole in it, that a 14awg fits. (comes with 24awg)
so i passed the bare 14 wire thru the rivet, and folded it over and soldered it to firm it up and reduce corrosion. On the neg it passes thru the spring, then folds over to contact the cell. the spring presses the copper wire against the cell. So if the OP wants to do this instead of spot weld or solder, i don't see a low-med power problem. would be easy to pop the cells out now and then, to clean contacts and test. I could see easy service as the pack weakens with age. Say the range is down 20%, after the ride, pop out the cells and do a 5 second high amp bench test. those that sag the most, get replaced. Or if they are pretty much even, you know it is time to replace, or add a 2nd pack in parallel.

Post Reply