Wattflyer RC Network: RC Universe :: RCU Magazine :: RCU Forums :: RCU Classifieds :: RCU User Reviews :: RCU YouTube
Home Who's Online Calendar Today's Posts RealTime Post Spy Mark Forums Read
Go Back   WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Power - Batteries, Chargers, ESCs and More > Batteries & Chargers
Register Members List Wattflyer Extras Articles Search Today's Posts Mark Forums Read Social Groups

Batteries & Chargers Discuss Li-P, Li-Ion, NiMh, Nicad battery technology and the chargers that juice 'em up!

Thank you for your support (hide ads)
Reply
 
Thread Tools Display Modes
Old 07-19-2009, 07:37 PM   #1
e-sailpilot86
Member
 
Join Date: Aug 2005
Posts: 39
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Default A123 2300 mAh soldering bars?

I see that hyperion makes some, I found a site that has them listed but with no price, probably out of stock. (aircraft-world) Where have others purchased them from? Cells are going to be on the way soon.
e-sailpilot86 is offline  
  Reply With Quote
Old 07-20-2009, 06:08 AM   #2
Larry3215
Look out for that tree!!!
 
Larry3215's Avatar
 
Join Date: Mar 2006
Location: Gig Harbor, Wa USA
Posts: 6,798
View Larry3215's Gallery63
Thanked 692 Times in 671 Posts
Club: Kitsap ARCS & E-FLAPS
Awards Showcase

90 Minute Thermal Duration  60 Minute Thermal Duration  30 Minute Thermal Duration  4kW 
iTrader: (6)
Friends: (21)
Default

I couldnt find any bars when I was building my packs so I used 12 ga solid coper electrical wire. I ran 3 strips between each cell for extra current handling and to lower the resistance.

I think I need a signature.
Larry
Larry3215 is offline  
  Reply With Quote
Old 07-20-2009, 04:41 PM   #3
Fast Guy
Member
 
Join Date: Feb 2008
Location: Ontario, Canada
Posts: 147
Thanked 21 Times in 19 Posts
iTrader: (0)
Friends: (0)
Default

I use the large size battery bars for assembling any Sub-C NiMH or NiCd battery packs. They don't reach center to center on the cells but do reach with good coverage on the sodering buttons on the A123's. Built 4 packs like this and they have many flights with no failures.
Fast Guy is offline  
  Reply With Quote
Old 07-20-2009, 04:43 PM   #4
Matt Kirsch
Super Contributor
 
Matt Kirsch's Avatar
 
Join Date: Jul 2005
Posts: 2,086
Thanked 70 Times in 68 Posts
iTrader: (0)
Friends: (1)
Default

Desoldering braid makes a great battery bar.
Matt Kirsch is offline  
  Reply With Quote
Old 07-20-2009, 04:48 PM   #5
kyleservicetech
Dennis V
 
kyleservicetech's Avatar
 
Join Date: Apr 2008
Location: Wisconsin, USA
Posts: 7,979
Thanked 692 Times in 674 Posts
Club: www.racinercclub.com (I'm the newsletter editor)
Awards Showcase

Outstanding Contributor Award  3kW  2kW  100mph Speed Demon 
iTrader: (1)
Friends: (20)
Default

mofosheee in another thread has used those "U" shaped copper hanger strips commonly used to hang copper pipe used in water pipes. Just make certain its pure copper, not some plated stuff, hammer it flat, cut it to shape, and solder away!

New 07-22-09
I just bought a package of these straps for 3/4 inch copper pipe at 10 pieces for $1.69, (made in China) Hammered flat, they measure 0.018 inches thick, 0.475 inches wide, and 3 inches long. Each piece can be cut in two, giving you 20 pieces for less than a dime each. The area of these straps is about equivalent to #10 wire.

I found that the straps I bought appear to be copper plated brass sheeting. A quick check with my high current power supply showed that each strap will have about a 0.01 volt drop at 50 Amperes, so a 6S2P pack would have about a 0.05 volt loss at 50 Amperes with five of these straps. FYI, watts equals volts X amps, or 0.01 X 50 or 0.5 watts, not nearly enough to cause any heat build up.

That voltage drop would be about 4 times less with pure copper bus bars, since the resistivity of brass is about 4X that of copper. So, take your choice, copper plated brass at your local hardware store, or pure copper straps that might be a little more difficult to obtain.


Take a look at the attached photo.


Attached Thumbnails
Click image for larger version

Name:	IMG_3418.jpg
Views:	189
Size:	92.7 KB
ID:	105866
kyleservicetech is online now  
  Reply With Quote
Old 07-20-2009, 08:02 PM   #6
e-sailpilot86
Member
 
Join Date: Aug 2005
Posts: 39
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Default

How easy/hard was it preventing the central vent from being clogged with solder?
e-sailpilot86 is offline  
  Reply With Quote
Old 07-20-2009, 08:08 PM   #7
Larry3215
Look out for that tree!!!
 
Larry3215's Avatar
 
Join Date: Mar 2006
Location: Gig Harbor, Wa USA
Posts: 6,798
View Larry3215's Gallery63
Thanked 692 Times in 671 Posts
Club: Kitsap ARCS & E-FLAPS
Awards Showcase

90 Minute Thermal Duration  60 Minute Thermal Duration  30 Minute Thermal Duration  4kW 
iTrader: (6)
Friends: (21)
Default

Central vent?

If thats supposed to stay open - then I screwed up on all mine!

I think I need a signature.
Larry
Larry3215 is offline  
  Reply With Quote
Old 07-20-2009, 09:02 PM   #8
e-sailpilot86
Member
 
Join Date: Aug 2005
Posts: 39
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Default

Uh oh.... Might want to fix that, even if it's with a tiny drill bit. Supposedly, if and when the cells do need to vent, it is not like a lipo going CATO, but it might pop a bit differently if it does get a bit under pressure.

I wanted the Hyperion solder tabs because they're great at keeping the central vent clear.

http://www.youtube.com/watch?v=vkDgoXikI_8
e-sailpilot86 is offline  
  Reply With Quote
Old 07-20-2009, 09:14 PM   #9
kyleservicetech
Dennis V
 
kyleservicetech's Avatar
 
Join Date: Apr 2008
Location: Wisconsin, USA
Posts: 7,979
Thanked 692 Times in 674 Posts
Club: www.racinercclub.com (I'm the newsletter editor)
Awards Showcase

Outstanding Contributor Award  3kW  2kW  100mph Speed Demon 
iTrader: (1)
Friends: (20)
Default

larry3125
Central vent?
If thats supposed to stay open - then I screwed up on all mine!

Interesting. I'm holding in my hand a two cell A123 pack built up by www.battlepack.com. Battlepack absolutely soldered shut both vents on the two cells.

Suspect that battlepack has been doing this awhile, so don't know just how important those vents are.

BTW, last year, I accidentally shorted out a cell on the Dewalt DC 36 volt batteries, burning a small hole right through one cell. All remaining cells are still in use, but that one cell with the hole in it went flat after a few months.:o I'd tried to solder it shut, but the case is aluminum so that didn't work. Tried to put a drop of epoxy on it to seal it up, but that epoxy slowly got a few bubbles in it, apparently from a very slight pressure inside the cell???

So, don't know if drilling a small hole in them would be a good idea.
kyleservicetech is online now  
  Reply With Quote
Old 07-20-2009, 09:15 PM   #10
Larry3215
Look out for that tree!!!
 
Larry3215's Avatar
 
Join Date: Mar 2006
Location: Gig Harbor, Wa USA
Posts: 6,798
View Larry3215's Gallery63
Thanked 692 Times in 671 Posts
Club: Kitsap ARCS & E-FLAPS
Awards Showcase

90 Minute Thermal Duration  60 Minute Thermal Duration  30 Minute Thermal Duration  4kW 
iTrader: (6)
Friends: (21)
Default

I have directly shorted my packs three times now. Two times there was enough current flow to melt the solder at one of the cells.

The second time one of the cells did fail, but there was no "event" at all and no noise.

The cell went to zero volts and that was that.

I'll definately keep it clear next time!

I think I need a signature.
Larry
Larry3215 is offline  
  Reply With Quote
Old 07-20-2009, 09:19 PM   #11
e-sailpilot86
Member
 
Join Date: Aug 2005
Posts: 39
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Default

Of course, having the cell vent clear assumes that it may vent at some point... I do not believe they regularly release gas like a lead acid. Keeping them clear is always a good idea anyway. That is why I do not like end to end soldering, not to mention the cells cannot be balanced when assembled that way. I purchased loose cells from battlepacks, they're going into a Maule and other models I already have. BTW, they are the new plastic wrapped cells that are slightly better than the cardboard wrapped ones. I think I'll make a parallel plug as well.
e-sailpilot86 is offline  
  Reply With Quote
Old 07-20-2009, 09:25 PM   #12
kyleservicetech
Dennis V
 
kyleservicetech's Avatar
 
Join Date: Apr 2008
Location: Wisconsin, USA
Posts: 7,979
Thanked 692 Times in 674 Posts
Club: www.racinercclub.com (I'm the newsletter editor)
Awards Showcase

Outstanding Contributor Award  3kW  2kW  100mph Speed Demon 
iTrader: (1)
Friends: (20)
Default

e-sailpilot86
Plastic wrapped? Is that the transparent light green wrapping with A123 systems labeled on it?

That's how my two cells came in from www.battlepack.com.
kyleservicetech is online now  
  Reply With Quote
Old 07-20-2009, 09:32 PM   #13
kyleservicetech
Dennis V
 
kyleservicetech's Avatar
 
Join Date: Apr 2008
Location: Wisconsin, USA
Posts: 7,979
Thanked 692 Times in 674 Posts
Club: www.racinercclub.com (I'm the newsletter editor)
Awards Showcase

Outstanding Contributor Award  3kW  2kW  100mph Speed Demon 
iTrader: (1)
Friends: (20)
Default

larry 3125
Directly shorted your A123 pack? Lets see, A123 rates their cells at between 0.01 to 0.015 ohms resistance, something I've verified with my 500 watt load resistor. Now, I=E/R or 3.3/0.015 or around 220 amperes out of that cell.

I used a Sears Craftsman #82369 DC clamp on ammeter to measure the starter current on my old Chev S10 pickup. That measured 135 Amps!

(That clamp on ammeter has DC ranges of 0-40 and 0-400 Amps, allows measuring current by just clamping its jaws around one of the battery conductors. I checked it against my Fluke 87V, its accurate to a percent or three!)
kyleservicetech is online now  
  Reply With Quote
Old 07-20-2009, 09:58 PM   #14
e-sailpilot86
Member
 
Join Date: Aug 2005
Posts: 39
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Default

Originally Posted by kyleservicetech View Post
e-sailpilot86
Plastic wrapped? Is that the transparent light green wrapping with A123 systems labeled on it?

That's how my two cells came in from www.battlepack.com.

Yes. Those are the ones I will be receiving. They all used to be like the DeWalt cardboard ones, the new ones have lower internal resistance, are a few grams lighter, and ship with the voltage in much tighter tolerances than the cardboard tube ones did. And mind you, someone on RCG (can't remember exactly... southern cross IFO avatar?) ran tests on the older style cells, with around 100 cycles, and didn't need balancing until a few cycles after 100. And they are still going strong. Future looks good for electrics, doesn't it!?
e-sailpilot86 is offline  
  Reply With Quote
Old 07-20-2009, 10:51 PM   #15
Larry3215
Look out for that tree!!!
 
Larry3215's Avatar
 
Join Date: Mar 2006
Location: Gig Harbor, Wa USA
Posts: 6,798
View Larry3215's Gallery63
Thanked 692 Times in 671 Posts
Club: Kitsap ARCS & E-FLAPS
Awards Showcase

90 Minute Thermal Duration  60 Minute Thermal Duration  30 Minute Thermal Duration  4kW 
iTrader: (6)
Friends: (21)
Default

Originally Posted by kyleservicetech View Post
larry 3125
Directly shorted your A123 pack? Lets see, A123 rates their cells at between 0.01 to 0.015 ohms resistance, something I've verified with my 500 watt load resistor. Now, I=E/R or 3.3/0.015 or around 220 amperes out that cell.

I used a Sears Craftsman #82369 DC clamp on ammeter to measure the starter current on my old Chev S10 pickup. That measured 135 Amps!

(That clamp on ammeter has DC ranges of 0-40 and 0-400 Amps, allows measuring current by just clamping its jaws around one of the battery conductors. I checked it against my Fluke 87V, its accurate to a percent or three!)
The cell voltage at those loads was probably more like 1/2 that value - under 2 volts certainly, but it was still a LOT of juice! The heat shrink melted over all the terminals and like I said - it de-soldered one cell!! After that I went to 3 (up from 2) 12 ga copper wires between each cell.

Originally Posted by e-sailpilot86 View Post
Yes. Those are the ones I will be receiving. They all used to be like the DeWalt cardboard ones, the new ones have lower internal resistance, are a few grams lighter, and ship with the voltage in much tighter tolerances than the cardboard tube ones did. And mind you, someone on RCG (can't remember exactly... southern cross IFO avatar?) ran tests on the older style cells, with around 100 cycles, and didn't need balancing until a few cycles after 100. And they are still going strong. Future looks good for electrics, doesn't it!?
Thats Charles (Everydayflyer) you're trying to remember. He is THE battery guy

And yes - it sure is looking good

I think I need a signature.
Larry
Larry3215 is offline  
  Reply With Quote
Old 07-20-2009, 10:54 PM   #16
kyleservicetech
Dennis V
 
kyleservicetech's Avatar
 
Join Date: Apr 2008
Location: Wisconsin, USA
Posts: 7,979
Thanked 692 Times in 674 Posts
Club: www.racinercclub.com (I'm the newsletter editor)
Awards Showcase

Outstanding Contributor Award  3kW  2kW  100mph Speed Demon 
iTrader: (1)
Friends: (20)
Default

e-sailpilot86
Agreed, I've cycled 250 Ampere Hours through each of my 6S2P A123 packs, and they have the same exact performance as when new, last year. That corresponds to a measured 11 hours of actual in the air flying time on each of my three 6S2P A123 packs. And, those A123 packs actually wore out my Walmart Engine Starting Deep Cycle battery in only one flying season!

My Great Planes "Revolver" is running a Hacker A40-10S motor, pulling 62 Amps full power on a 14X10 APC-E prop, turning at 7850 RPM with a 6S2P A123 pack. Model has been tracked at 88 MPH, straight and level.
kyleservicetech is online now  
  Reply With Quote
Old 07-21-2009, 06:59 AM   #17
e-sailpilot86
Member
 
Join Date: Aug 2005
Posts: 39
Thanked 0 Times in 0 Posts
iTrader: (0)
Friends: (0)
Default

Everydayflyer, that's him. I find it amazing how many batteries he gets to go through AND how many times he uses them. He is the man when it comes to finding the good batteries to buy. And the charts and graphs.... perfect, why I don't do that myself... I should! I think I might be able to with my new charger, it only charges though, no discharging. (TME Xtrema...)

11 hours of flying... that is spectacular! I've had some of my lipos be not so good after even 5 cycles!
e-sailpilot86 is offline  
  Reply With Quote
Old 07-21-2009, 08:20 PM   #18
kyleservicetech
Dennis V
 
kyleservicetech's Avatar
 
Join Date: Apr 2008
Location: Wisconsin, USA
Posts: 7,979
Thanked 692 Times in 674 Posts
Club: www.racinercclub.com (I'm the newsletter editor)
Awards Showcase

Outstanding Contributor Award  3kW  2kW  100mph Speed Demon 
iTrader: (1)
Friends: (20)
Default

e-sailpilot86
New charger can't discharge?
One of the past members of our club had a very nice gasoline powered (Twin G26?) Twin engine Model that he flew several years ago. Very shortly after take off, he lost all radio control. The model crashed full speed about 1/4 mile away. Total loss, even the two engines were busted up.

Cause, he had just picked up a new nicad battery charger/cycler. And, he used it on the new receiver battery. Problem was, he misread the charger instructions, and discharged the pack, rather than charging it. Took off with a freshly disharged battery. The model was worth well over a grand.
kyleservicetech is online now  
  Reply With Quote
Reply

  WattFlyer RC Electric Flight Forums - Discuss radio control eflight > R/C Electric Power - Batteries, Chargers, ESCs and More > Batteries & Chargers

« Previous Thread | Next Thread »

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale A123 cells, 2300 size JWilliams Batteries and Chargers Forsale/WTB 11 01-14-2009 05:25 PM
A123 / BlaCK & DECKER vpx 1100 mAh everydayflyer Batteries & Chargers 31 11-12-2008 05:36 PM
Hitec Neon problem in FMS - Bars 1-4 blank Wayne Miles Flight Simulators 2 02-18-2008 11:36 PM
Method for fixing brocken skid bars Tyrant Blaze Beginners - Helis 2 01-24-2008 10:58 AM
so who is flying the A123 / BlaCK & DECKER vpx 1100 mAh ?packs? EpoweredRc Batteries & Chargers 11 12-23-2007 10:55 PM


All times are GMT +1. The time now is 07:05 AM.


Powered by: vBulletin
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright 2005 WattfFlyer.com
RCU Eflight HQ

Charities we support Select: Yorkie Rescue  ::  Crohn's & Colitis Foundation



Page generated in 0.28997 seconds with 56 queries