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Soldering question

FrannyFranny Posts: 127
in General Discussion
Howdy, I have a can of CRC QD Contact Cleaner (02130) and was wondering if it's good for cleaning before applying flux and solder? I'm soldering lithium-ion batteries to pure nickel tabs with flux and silver bearing solder, I need it to be very sturdy and saw that people use Alcohol for cleaning before applying flux, what do you recommend?

http://www.homedepot.com/p/CRC-QD-11-oz-Contact-Cleaner-02130-6/202262505

Comments

  • LeonLeon Posts: 7,620
    Check that it doesn't contain a lubricant, which will prevent a decent joint being made. IPA (iso-propyl alcohol) would be better.


  • FrannyFranny Posts: 127
    It says "Leaves no residue" but anyways where do you get 100% pure ISO-propyl alcohol other than online?
  • PublisonPublison Posts: 12,366
    The 91 %, from CVS, Walgreens, is usually good enough. I get my drug store to order 99% for me, and I usually get it the next day.
  • LeonLeon Posts: 7,620
    Electrolube sells 99.7% IPA. I've had a can of it for many years - it lasts a long time.
  • Hal AlbachHal Albach Posts: 747
    I have used a super low tech rubber eraser for years to clean metal surfaces for soldering. I clean the black buildup on the eraser by rubbing it on a denim cloth.
  • ercoerco Posts: 20,256
    edited 2016-05-22 14:05
    You guys are hardcore. My preferred IPA has an alcohol content of only about 5%.
  • kwinnkwinn Posts: 8,697
    erco wrote: »
    You guys are hardcore. My preferred IPA has an alcohol content of only about 5%.

    But...but, that leaves a residue, lubricates the thought processes, and using it to clean surfaces is such a waste.
  • PublisonPublison Posts: 12,366
    edited 2016-05-22 15:58
    Hal Albach wrote: »
    I have used a super low tech rubber eraser for years to clean metal surfaces for soldering. I clean the black buildup on the eraser by rubbing it on a denim cloth.

    Been using that trick also since the 70's on copper/gold board edge fingers.

    Also used a fiberglass brush:

    http://www.mcmelectronics.com/product/21-13835

    but it is pretty aggressive.
  • FrannyFranny Posts: 127
    Hal Albach wrote: »
    I have used a super low tech rubber eraser for years to clean metal surfaces for soldering. I clean the black buildup on the eraser by rubbing it on a denim cloth.

    I have heard of the rubber thing, lots of folks use it, however, this is a lithium-ion battery for a vehicle with 156 fuses, lots of soldering points and most important lots of vibration and so because these batteries are so expensive I want to make sure I get it right

  • Hal AlbachHal Albach Posts: 747
    Publison: "Been using that trick also since the 70's on copper/gold board edge fingers.

    Also used a fiberglass brush:"

    Tried those also until I wound up with fiberglass slivers in my fingers. Not a pleasant thing...
  • FrannyFranny Posts: 127
    fiber glass has so many useful uses but working with it is an itchy nightmare and also unhealthy
  • PublisonPublison Posts: 12,366
    800 grit sandpaper, alcohol clean, then flux should do it for big tabs like that.
  • FrannyFranny Posts: 127
    Publison wrote: »
    800 grit sandpaper, alcohol clean, then flux should do it for big tabs like that.

    90% alcohol OK?
  • Phil Pilgrim (PhiPi)Phil Pilgrim (PhiPi) Posts: 23,514
    edited 2016-05-22 19:23
    Franny wrote:
    ... this is a lithium-ion battery for a vehicle with 156 fuses, lots of soldering points ...
    That raised a flag in my mind. Are absolutely sure those are soldering points and not designed for spot welding -- or even push-on connectors? Soldering directly to a lithium battery can be dangerous if the battery heats up during the process.

    -Phil
  • PublisonPublison Posts: 12,366
    Phil Pilgrim (PhiPi) wrote: »
    Franny wrote:
    ... this is a lithium-ion battery for a vehicle with 156 fuses, lots of soldering points ...
    That raised a flag in my mind. Are absolutely sure those are soldering points and not designed for spot welding -- or even push-on connectors? Soldering directly to a lithium battery can be dangerous if the battery heats up during the process.

    -Phil

    Good call Phil. I'd go for push ons myself.

  • PublisonPublison Posts: 12,366
    Franny wrote: »
    Publison wrote: »
    800 grit sandpaper, alcohol clean, then flux should do it for big tabs like that.

    90% alcohol OK?

    Got a pic of what to want to connect?


  • FrannyFranny Posts: 127
    Phil Pilgrim (PhiPi) wrote: »
    Franny wrote:
    ... this is a lithium-ion battery for a vehicle with 156 fuses, lots of soldering points ...
    That raised a flag in my mind. Are absolutely sure those are soldering points and not designed for spot welding -- or even push-on connectors? Soldering directly to a lithium battery can be dangerous if the battery heats up during the process.

    -Phil
    has to be fast, people do it all the time, some folks use coolant spray cans.
  • FrannyFranny Posts: 127
    Alright guys, so these are my cleaning choices right now, which one would you choose?
    solder contact cleaners.jpg
    4320 x 2432 - 2M
  • Peter JakackiPeter Jakacki Posts: 10,193
    edited 2016-05-23 02:22
    Many many years ago when Lithium batteries were a rarity I had to somehow fit these tiny cylindrical batteries with a cathode body and the center pin to my production pcbs. I tried silver solder etc but you need so much heat that it damages the battery and there were no ots connector solutions. My solution was to wrap wire tightly around the body and the pin and then tin up the wrap itself with the wire ends soldered to my board. I'd probably be inclined if I did it the same way these days to use some aluminum foil first before wrapping the wire just to provide that more intimate connection although I never had any problems and they worked year after year. Anyway this is a method to solder to "unsolderable" connections whether that's because of the metal or the heat or both.
    Franny wrote: »
    Howdy, I have a can of CRC QD Contact Cleaner (02130) and was wondering if it's good for cleaning before applying flux and solder? I'm soldering lithium-ion batteries to pure nickel tabs with flux and silver bearing solder, I need it to be very sturdy and saw that people use Alcohol for cleaning before applying flux, what do you recommend?

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