Beginners Guide to Processing 18650 Cells | Cell Database


Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Spot weld residuals
#1
The cells I'm breaking apart are currently spot welded.  I can pull the majority off easily enough, but there are small remnants too small for pliers to grab.

Any advice on removing these bits?  Dremel?  Chisel?

Here's a pic to be clear what I'm talking about.


Attached Files Thumbnail(s)
   
Reply


#2
I just flatten mine on the bench and don;t worry about it
Korishan likes this post
Reply
#3
I just tap them down with the side of my pliers. No need to try picking them off.
Korishan likes this post
Reply
#4
Thanks for replies.  Does it make a difference if you're going to spot weld the end vs. solder?
Reply
#5
(09-07-2017, 05:47 PM)Travis Watson Wrote: Thanks for replies.  Does it make a difference if you're going to spot weld the end vs. solder?

Soldering doesn't matter, I just solder right over them. I would think you need as clean a surface as possible for spot welding, not sure since I have never tried it personally. If you're concerned, you can very carefully tap the end of the cell against a bench grinder to remove the nub that's left.
Reply
#6
Spotwelding you need to have it a bit cleaner otherwise you might get issues getting proper contact.
mike likes this post
Follow me! >> YouTube / Forum system setup / My webpage  Diy Tech & Repairs

Current: 10kW Mpp Hybrid | 4kW PIP4048 | 2x PCM60x | 83kWh LiFePo4 | 10kWh 14s 18650 |  66*260W Poly
Upcomming: 14S 18650~30kWh | Automatic trip breakers, and alot more
Reply
#7
(09-07-2017, 06:46 PM)daromer Wrote: Spotwelding you need to have it a bit cleaner otherwise you might get issues getting proper contact.

Hey gang.
On the same lines, what about damage to the cells when removing the tin/nickel strip with force?
I'm fairly careful (using small nips) to curl off the metal strip from the batteries, but in a lot of cases, they just get "ripped off", leaving some spot weld pieces.  I nip them and make as smooth as possible, but.... I've seen that some people "press" the remains back down with pliers, wooden mallets, and even tap them with hammers on the workbench to make smooth and flat.

Sure, A good reason for as smooth and flat as possible is to ensure a good connection to the chargers/dischargers, etc.

Thinking about it, as for re-soldering, and keeping things flat, why not just leave the tin/nickel piece on the anode and cathode and carefully snip them with sharp cutters.
This way, we don't rip the spot welds or the metal strip off the battery, potentially bending the ends and leaving spot weld pieces.

Question to the group - is it "easier" to solder onto the tin/nickle strip?  I have found no difference.  However, by leaving the metal piece and the spot weld there, does it cause any residual heat inside the battery when soldering to the remaining metal strip, as compared to soldering directly to the bare battery ends?

What about the holes left when pulling the spot-welded strip off the batteries?   What about the CID's? Do they get damaged when we "tap" on them, or pull the metal from them?

I'm just looking for some safety rules of thumb and other's experiences.

Thanks Smile
                                 ''~``
                                ( o o )
+--------------------------.oooO--(_)--Oooo.-----------------------------+
|                                                                        |
|   Howie Grapek                        South Florida, USA               |
|   cell: 303.818.9414                  email: howiegrapek@yahoo.com     |
|   phone: 561-819-9988                 http://www.howieshomestead.com   |
|                            .oooO                                       |
|                            (   )   Oooo.                               |
+-----------------------------\ (----(   )-------------------------------+
                               \_)    ) /
                                     (_/

Reply
#8
The Nickel strips are softer than the shell of the cell. So, ripping the strip off generally will do no harm to the cell. However, there are few times when the weld is so darn good that it does rip a hole. Rolling the strip to remove it is a good practice to have as it makes the strip tear if the weld is too good.

I don't believe there is an added benefit nor a negative impact by leaving a little strip behind. If you solder onto the cell, there isn't going to be more or less heat applied to the area, unless you have quite a bit of strip there.

It's a good idea to tap the shards left by the removal process down a bit so as to not impeded the connection with the chargers. I usually just use the same pliers I'm pulling with to gently tap them flat again.

It is also a good idea to just remove the tabs all together. Reason being that all welds are not equal. Some welds are just piss poor and will create a lot of heat at those spots. Unless you have a pack that generally is hard to pull the strips off to begin with, then I'd remove them.

There are different methods of removal. Rolling with pliers is by far not the only option. You could snip the strip as close as possible with flush snips, then use a small flat head screwdriver (or something similarly small) to go under the strip to raise it up, then flush snip from underneath. The idea really is to not pull straight away from the cell as this greatly increases the chance of ripping a hole in the cell.
Proceed with caution. Knowledge is Power! Literally! Cool 
Knowledge is Power; Absolute Knowledge is Absolutely Shocking!
Dollar Shave Club. Best Razor I've ever used
Certified 18650 Cell Reclamation Technician
Reply
#9
So, are the little holes bad???
                                 ''~``
                                ( o o )
+--------------------------.oooO--(_)--Oooo.-----------------------------+
|                                                                        |
|   Howie Grapek                        South Florida, USA               |
|   cell: 303.818.9414                  email: howiegrapek@yahoo.com     |
|   phone: 561-819-9988                 http://www.howieshomestead.com   |
|                            .oooO                                       |
|                            (   )   Oooo.                               |
+-----------------------------\ (----(   )-------------------------------+
                               \_)    ) /
                                     (_/

Reply
#10
If there are holes, then yes. You can tell if there is a hole if you smell the electrolyte. You'll know it when you smell it. Very distinct smell
Proceed with caution. Knowledge is Power! Literally! Cool 
Knowledge is Power; Absolute Knowledge is Absolutely Shocking!
Dollar Shave Club. Best Razor I've ever used
Certified 18650 Cell Reclamation Technician
Reply


Who read this thread?
63 User(s) read this thread:
AmDD (10-31-2017, 02:07 AM), accoelho (10-25-2017, 04:46 PM), Tridge17 (10-23-2017, 08:30 PM), Oz18650 (10-17-2017, 11:32 PM), dougm352 (10-18-2017, 08:00 PM), howiegrapek (10-25-2017, 06:33 PM), Tostaki (10-25-2017, 06:57 PM), Kryphon (10-28-2017, 11:31 PM), Sonic01 (10-23-2017, 09:53 PM), jesse.rizzo (10-22-2017, 03:02 PM), ChrisD5710 (10-26-2017, 01:31 PM), _claude (10-11-2017, 08:26 PM), v850tw (09-07-2017, 06:47 PM), Thomas Koorneef (09-08-2017, 01:10 PM), neurocis (10-17-2017, 10:19 PM), morpheus9869 (10-26-2017, 08:19 PM), rev0 (10-17-2017, 09:24 PM), Gbear34 (10-29-2017, 04:40 PM), garolittle (10-30-2017, 01:41 AM), macallazack (10-26-2017, 05:28 AM), kennl (10-25-2017, 10:59 PM), spyroslo (10-17-2017, 06:05 PM), without (10-17-2017, 05:20 AM), not2bme (10-28-2017, 01:06 PM), youyoung21147 (10-27-2017, 06:47 PM), Elecjim (10-26-2017, 07:51 PM), okent (10-17-2017, 09:31 PM), BCB (11-01-2017, 03:26 PM), shonalex (10-21-2017, 06:15 PM), Bryn (10-17-2017, 12:21 PM), hOOPSNAKE (10-17-2017, 06:18 AM), TimFr (11-06-2017, 07:38 PM), Grumplestiltskin (10-18-2017, 07:01 PM), Jeremy Choy (09-07-2017, 07:10 PM), frnandu (10-25-2017, 03:58 PM), wim (10-25-2017, 06:13 PM), jdeadman (10-25-2017, 04:37 PM), flight4900 (09-08-2017, 01:53 PM), Frnandu Martiński (10-24-2017, 10:10 AM), Wattsup (10-26-2017, 12:22 AM), Batrium (10-17-2017, 05:02 AM), Prahe86 (09-07-2017, 04:48 PM), alfu (10-23-2017, 07:34 PM), Korishan (10-25-2017, 03:55 PM), Majorphill (10-18-2017, 09:45 AM), mike (10-25-2017, 04:32 PM), watts-on (10-25-2017, 04:45 PM), Hanssing (10-26-2017, 04:20 AM), Stefaan De Ridder (10-26-2017, 09:20 AM), Swake (09-08-2017, 12:22 PM), brol (11-01-2017, 05:59 AM), SimonW (09-08-2017, 04:59 AM), Jon (10-23-2017, 07:48 PM), Geek (10-26-2017, 12:46 AM), ivnz (10-17-2017, 06:06 AM), prads34 (09-07-2017, 05:18 PM), paraskevas (10-25-2017, 04:01 PM), Travis Watson (09-07-2017, 09:46 PM), Eric Koshinsky (10-25-2017, 03:42 PM), SolarWind (09-08-2017, 05:51 PM), BlueSwordM (10-18-2017, 01:41 AM), Chicken (10-18-2017, 05:57 AM), daromer (10-17-2017, 08:05 PM)

Forum Jump:


Users browsing this thread: 1 Guest(s)