Worst case of Lithium battery leakage I've ever seen! - Page 1
Forum section: electronics / repair

author: Jwalling
author_rank: Unknown
timestamp: May 17, 2018, 04:54:36 pm
content: Passive ISA CPU board is beyond repair; at least 1 pin on a flatpak gone, traces and pads eaten and corroded.Nasty...

author: Jwalling
author_rank: Unknown
timestamp: May 17, 2018, 05:16:12 pm
content: CPU is like this one:https://www.ebay.com/itm/192539449993?Instrument is a Ruska Instrument Corp. 7010-715. Some sort of pressure controller.Battery is a QTC85. If I had any equipment with this battery in it, I'd replace it ASAP!

author: ElektroQuark
author_rank: Unknown
timestamp: May 17, 2018, 05:22:43 pm
content: If the equipment is badly needed, maybe it can be fixed.The IC package can be sanded (with a DREMEL or equivalent) from the top of the pin until the remaining rest of the pin inside is exposed. Then, solder a wire to it.It's doable.

author: Jwalling
author_rank: Unknown
timestamp: May 17, 2018, 06:05:01 pm
content: Quote from: ElektroQuark on May 17, 2018, 05:22:43 pmChances are that the corrosion has crept into the package, and the other pins and pads are pretty shaky looking. For $350 or so, it's better to replace the board and have it be reliable. Luckily there's some around to be had.

author: bob225
author_rank: Frequent Contributor
timestamp: May 17, 2018, 06:23:02 pm
content: you should see some of the arcade machines when the batteries leak, the only thing that left in the board, that's repairable - if you can get a replacement chip

author: Rasz
author_rank: Super Contributor
timestamp: May 17, 2018, 06:32:18 pm
content: $20 plus 20 minutes of cleaning and solderinghttps://www.ebay.com/itm/PC87311AVF-PC87311-National-Semiconductor-IC/360475665531

author: LeonR
author_rank: Regular Contributor
timestamp: May 17, 2018, 08:53:31 pm
content: Is there any "leak-proof" (to a certain extent) battery or battery shell? It saddens me when I see good old tech destroyed by a leakage.

author: Rasz
author_rank: Super Contributor
timestamp: May 17, 2018, 10:21:39 pm
content: Quote from: LeonR on May 17, 2018, 08:53:31 pmsure, old RTC chips with battery encapsulated in plastic on top od DIP carrier dont leak afaikhttp://www.retrotechnology.com/herbs_stuff/dallas_1.jpg

author: floobydust
author_rank: Super Contributor
timestamp: May 17, 2018, 10:30:41 pm
content: I've seen many Tadiran lithium batteries do that, the stainless steel BEL case corrodes at the laser weld seam.This is around the 5 year mark in product using the TL-5186, TL-2186, TL-4986 all discontinued Jan. 2015 and replaced by bigger TL-2450. I don't know how that will last or if the seal design has been fixed.I did send pics to Tadiran because it is dangerous and not meeting their lifetime claims.

author: Jwalling
author_rank: Unknown
timestamp: May 17, 2018, 11:31:09 pm
content: https://www.ebay.com/itm/231588655776?Got it for $125 with an offer.

author: james_s
author_rank: Super Contributor
timestamp: May 17, 2018, 11:42:27 pm
content: I've seen worse. I have a Mac IIfx motherboard that suffered a lithium battery leak, multiple SMT components vanished entirely, a bunch of traces rotted out. Even the case was damaged, all the sheetmetal shielding rusted badly.I scrapped a Mac SE/30 that had suffered the same fate, motherboard destroyed and the metal frame was all rusted.

author: helius
author_rank: Super Contributor
timestamp: May 18, 2018, 01:13:33 am
content: Quote from: james_s on May 17, 2018, 11:42:27 pmDid they have Maxell Japan lithium cells?

author: james_s
author_rank: Super Contributor
timestamp: May 18, 2018, 03:46:36 am
content: Quote from: helius on May 18, 2018, 01:13:33 amI think one of them did, the other I don't know. It was several years ago that I got them, the batteries long since disposed of.

author: amyk
author_rank: Super Contributor
timestamp: May 18, 2018, 04:31:08 am
content: That's a lithiumthionyl chloridecell --- much nastier chemistry than typical lithium primary or lithium ion. Be careful with the contents!

author: helius
author_rank: Super Contributor
timestamp: May 18, 2018, 04:34:19 am
content: Yes, SOCl2is toxic, but despite that the cells were used in desktop computer clock/cmos applications for decades.

author: KL27x
author_rank: Super Contributor
timestamp: May 18, 2018, 04:44:39 am
content: QuoteCertainly doable, if the corrosion doesn't go too deep. I have done this.Here's another trick you might like. I keep around a bit of very thin single sided copper clad (0.007-8" thick, single sided... used for RF shielding and such) with carpet tape on the back. Cut out a tiny rectangle and stick it to the top of the chip. Score a line partway down the middle to make two thermally isolated pads. Now you can wire a jumper between the sanded pin and one pad. Then after putting the chip back in, you can add a second jumper between the copper clad and the PCB without disturbing the delicate connection to the side of the chip. That is a lot easier than trying to flow them both at the same time and trusting the connection you can't see... or physically push on to test, because the wire between pcb and chip is so darn short and solder-laden that it has the flexibility of a tree trunk.