Home |
Search |
Today's Posts |
|
Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
Reply |
|
LinkBack | Thread Tools | Display Modes |
#1
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
When NiCads leak, what's the best substance to neutralize the spill?
[not NiMh; NiCad...] -- A host is a host from coast to & no one will talk to a host that's close........[v].(301) 56-LINUX Unless the host (that isn't close).........................pob 1433 is busy, hung or dead....................................20915-1433 |
#2
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
David Lesher wrote:
When NiCads leak, what's the best substance to neutralize the spill? [not NiMh; NiCad...] Maybe vinegar? The electrolyte is lye (either KOH or NaOH) so a mild acid should neutralize it. But, it is darn corrosive stuff, so it will eat many materials pretty quickly. Jon |
#3
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
On Mon, 08 Oct 2012 16:13:38 -0500, Jon Elson
wrote: David Lesher wrote: When NiCads leak, what's the best substance to neutralize the spill? [not NiMh; NiCad...] Maybe vinegar? The electrolyte is lye (either KOH or NaOH) so a mild acid should neutralize it. But, it is darn corrosive stuff, so it will eat many materials pretty quickly. Jon The KOH electrolyte is at about 30% concentration for a pH of about 12. Strong stuff, but not really dangerous. Any acid will wash off the KOH but may leave salts behind. (That's what's left when the KOH attacks aluminum, tin, brass, bronze, lead, zinc, etc). For KOH cleanup, the MSDS sheet recommends dilute acetic acid (vinegar). http://www.westernu.edu/bin/safety/msds/urc/potasium%20hydroxide.pdf For cleaning up the salts, I use baking soda, 409 cleaner, or whatever household cleaner I have handy that evaporates and doesn't leave a mess. Note that cadmium is a hazardous waste. Dead NiCd batteries should be properly disposed of, not mixed with the household trash. Mo http://cleaning.lovetoknow.com/How_to_Clean_Leaking_AA_Batteries Incidentally, the KOH does not enter into the chemical reactions inside the battery and just acts as a conduit for the ion exchange. The KOH concentration is the same for a brand new charged NiCd battery, as it is for an old dead battery. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
#4
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
David Lesher wrote:
When NiCads leak, what's the best substance to neutralize the spill? [not NiMh; NiCad...] http://www.flippers.com/battery.html John :-#)# -- (Please post followups or tech enquiries to the newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out." |
#5
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
"David Lesher" When NiCads leak, what's the best substance to neutralize the spill? ** Not the way to do it at all. The spill needs to be simply removed - so use tissue and/or clean rags to get up the worst of it, then use the same dipped in methylated spirits to get the surfaces clean as possible. Slight surface corrosion can be treated with WD40. Any spillage that has become trapped in crevices or small holes must be washed out ( use a toothbrush ) and the item dried with hot air. Pouring acid onto alkali inside some piece of equipment is BARKING MAD !! ..... Phil |
#6
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
"Phil Allison" wrote:
"David Lesher" When NiCads leak, what's the best substance to neutralize the spill? ** Not the way to do it at all. The spill needs to be simply removed - so use tissue and/or clean rags to get up the worst of it, then use the same dipped in methylated spirits to get the surfaces clean as possible. Slight surface corrosion can be treated with WD40. Any spillage that has become trapped in crevices or small holes must be washed out ( use a toothbrush ) and the item dried with hot air. Pouring acid onto alkali inside some piece of equipment is BARKING MAD !! .... Phil Ok. I had to look up methylated spirits. Sometimes I just use tap water, but on good stuff I then use those methylated stuff. Then wd-40 or crc 2-26. Hot air sometimes. http://blekko.com/ws/methylated+spirits Greg |
#7
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
Phil Allison wrote:
"David Lesher" When NiCads leak, what's the best substance to neutralize the spill? ** Not the way to do it at all. The spill needs to be simply removed - so use tissue and/or clean rags to get up the worst of it, then use the same dipped in methylated spirits to get the surfaces clean as possible. Slight surface corrosion can be treated with WD40. Any spillage that has become trapped in crevices or small holes must be washed out ( use a toothbrush ) and the item dried with hot air. Pouring acid onto alkali inside some piece of equipment is BARKING MAD !! ..... Phil Well, actually, using a mild acid to neutralize the mild alkali that leaked is the only way to be sure you have removed the corrosion risk. Simply washing with pure water isn't quite enough - a 50/50 solution of water and white vinegar will often bubble even after you have washed the area. So, scrub some of the 50/50 mixture into the leakage area, then wash with lots of water. Look for possible alkali leakage under conformal coatings over the PCB copper traces as they can be a bit of a time bomb if not the coating is not scrapped back a bit, then neutralized as well. Lift/remove connectors - you'd be surprised how little alkali it takes to eat under these! Once finished protect with a spray conformal coating. Not sure how many ni-cad leakage logic boards you have dealt with, but I'd repaired hundreds. John :-#)# -- (Please post followups or tech enquiries to the newsgroup) John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9 Call (604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games) www.flippers.com "Old pinballers never die, they just flip out." |
#8
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
I had to look up methylated spirits.
To change the subject a bit... The origin of the word "alcohol" is fascinating, among the most-interesting I've ever come across. Would you believe that it's related to mascara? http://en.wikipedia.org/wiki/Mascara http://en.wikipedia.org/wiki/Alcohol Ethyl alcohol is distilled from water/alcohol solutions, hence it is "the fine part of" the solution ("fine" as in small, not good). |
#9
Posted to sci.electronics.repair
|
|||
|
|||
Nicad leakage
Jeff Liebermann frembragte:
Note that cadmium is a hazardous waste. Dead NiCd batteries should be properly disposed of, not mixed with the household trash. Yeah. I once made a dumpster dive, when I discovered the boss had dumped several boxes of used NiCd's in the regular trash. Don't ever do that again, I told him... Leif -- Husk kørelys bagpå, hvis din bilfabrikant har taget den idiotiske beslutning at undlade det. |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Thread Leakage ... | UK diy | |||
Is this electrolyte leakage? | Electronics Repair | |||
battery leakage | Home Repair | |||
Snowblower And Oil Leakage ? | Home Repair | |||
NiCad | Electronics |