IBM Thinkpad BIOS battery. Can I DIY? - Page 1
Forum section: electronics / repair

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: April 05, 2015, 12:15:49 am
content: http://www.ebay.com/itm/IBM-Thinkpad-R50-R50e-R51-CMOS-battery-02k7078-08k8050-/110774034816Apparently it is just a coin cell in that yellow package. Rather than buying, thinking about just repairing this myself using the old wires and connector and a new battery. Not sure how to solder or re-seal it.Any ideas?

author: Monkeh
author_rank: Super Contributor
timestamp: April 05, 2015, 12:28:15 am
content: They use spot welded tabs. Soldering to a normal coin cell isn't generally recommended..Heatshrink will do to wrap one up..

author: wraper
author_rank: Unknown
timestamp: April 05, 2015, 12:32:53 am
content: You cannot solder the battery directly or it will be damaged by the heat. You would need either to spot weld the wires or buy the battery with some pins already spot welded like on the picture and solder wires to the pins. Or if there is enough space, you could buy battery holder lite this:http://www.ebay.com/itm/Vertical-CR2032-2025-Half-Round-Battery-Coin-Button-Socket-3-PIN-Holder-Case-new-/400844615558?pt=LH_DefaultDomain_2&hash=item5d54336f86and solder wires to it.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: April 05, 2015, 01:31:01 am
content: Might be better of just getting the replacement part.Thanks. O0

author: pickle9000
author_rank: Super Contributor
timestamp: April 05, 2015, 01:55:56 am
content: I normally use a holder (pcb) and solder wires on. A chunk of heat shrink and hot glue. Makes em easy to change.

author: MLXXXp
author_rank: Frequent Contributor
timestamp: April 05, 2015, 01:58:02 am
content: Years ago, when the BIOS battery (which is similar, if not identical, to the one for the R50) in my ancient ThinkPad T22 died, I was able to squeeze a CR2032 cell holder into the chamber where the battery sits. I had to cut away some of the plastic of the retainer to make it fit. I used the wires and connector from the original battery. I held the cell holder in with double sided tape.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: April 05, 2015, 04:35:58 am
content: That's my concern with the battery holder. I'd prefer not to need to hack the hell out of the case if possible. Hacking it however, to have the ability to change the battery in future is a good ideabut I'm not sure if the machine will need to last as long as another bios battery...

author: HighVoltage
author_rank: Super Contributor
timestamp: April 05, 2015, 07:48:11 am
content: I agree, use a new battery with spot welded pins already installed.Since I have been using only Thinkpads in the last 20 years, I have done this procedure many times.

author: paulhm81
author_rank: Regular Contributor
timestamp: April 05, 2015, 06:45:04 pm
content: Do not try to solder wires on the battery because I tried that once not knowing that it would damage it and it exploded from the pressure. You can put wires on it with heat shrink tube and it works or you can use tape.

author: Ian.M
author_rank: Super Contributor
timestamp: April 05, 2015, 07:08:15 pm
content: Just Google: tagged CR2032I have soldered to CR2032 cells successfully before, but its *STRONGLY* not recommended as even if it doesn't explode in your face, the heat is highly likely to damage the internal structure or the seal resulting in early failure.

author: Ed.Kloonk
author_rank: Super Contributor
timestamp: April 06, 2015, 07:03:04 am
content: I picked up a this from Jaycar... (Part: SB-1762 if the above pic doesn't show.)Slipped tiny heat shrink on the tiny wires and soldered them to the tabs. Battery got alittlewarm after using the heat gun. Chopped of the extra + tab. Then found a monster sized heat shrink and cut a small piece to cover the whole battery. Measured battery voltage before and after. Might have lost about 50mV after all the heating. ~3.2v. Should have taken a photo.Put it all back together and no screws left over! More importantly, the lappy no longer has an identity crisis.O0