Comments on: Rebuilding a PowerBook G4 Battery

By: Alexander

Alexander — Sat, 20 Aug 2022 12:19:17 +0000

@Austin Farley
yes, 18650

By: Austin Farley

Austin Farley — Mon, 13 Sep 2021 23:38:19 +0000

Just to make sure we’re on the same page, these are 18650 cells right?

By: Harlan Ulrich

Harlan Ulrich — Sun, 30 Apr 2017 13:24:27 +0000

I recently rescued a PowerBook G4 Ti from a recycle shop, fired up fine after installing a hard drive. The original battery was in it still and took a charge but only held it for ten minutes before shutting down, tried ‘reconditioning’ it but that did not work and replacements were out of my budget for a couple reasons. Began exploring the rebuild angle and had everything apart before realizing I had not marked my steps at all and happened upon your blog while looking for a schematic. One strap was tatered during the removal process so I had to make a jumper, plus the white wire that runs underneath fell off and got shortened so it needed replacing as well.
I went the route of new replacements over scavenging used, followed your original drawing and I have to say I am very happy with the results, I have over three hours of usage at this point. I have no idea how the original batteries performed but what I have now is significantly better than ten minutes. Odec makes a 3000miah lithium ion battery that comes in packs of four with flat tops; a little emery cloth helps them accept a bead of solder prior to assembly. Thanks for your help with the information in your blog!

By: b

Wed, 28 Jul 2010 21:48:48 +0000

Hi all, i rebuilt my powerbook battery with known good cells from a 12″ but…same poor results as original, its not the cells but the chipset in the connection block, tried all the known resets and wipes, any advice as to convincing the battery brain to accept the transplant? Please email me at kinematographer@gmail.com, as the ebay replacement went cold after 2 months!

By: Peter

Peter — Sun, 16 May 2010 16:10:22 +0000

Keith:

A couple comments on this procedure:

One, you really should use new cells, as Li-Ion cells die of old age fairly quickly, and also from being kept fully charged and not cycled. The internal resistance tends to climb due to deposition of something on the carbon electrode, and although deep cycling can help, it’s not fully reversable.

Two, you must make very sure that all solder connections are good. I use a very large iron my father bought in the 1940′s for this job. Great care must be taken to not fry the cells, but you need lots of heat and fresh flux to get that stainless steel to accept a decent solder connection.

Three: if you cannot find tabbed replacement cells, use 0.010″ thick brass shim stock cut into 1/8″ strips (wider is OK) to connect the cells. This won’t leave you will pacs that won’t fit into the case, as happened to me with some Lombard batteries when I first tried to rebuild batteries. You must then solder on some extra strips to connect the wires.

Four: It’s critical that the connections between the wires and battery are good — if not, the PCB won’t update the capacity and you will end up like I did with a battery that only “saw” 100 mAh capacity and kept switching off the computer on me. I found a cold solder joint on one connecting strip.

Five: Insulate the ends of the batteries. Use the old paper if you can, otherwise heavy tape. Shorts are a bad thing with li-ions.

Six: I have had trouble finding reasonable price cells lately. I spent $70 for a set of 8 18650 2600 mAh cells for my G4 Titanium, and that’s as much as a new battery. I will be attempting a re-cell with some Ultra-Fire cells (after taking off the protective circuit), we shall see how that goes. I’ve heard they are highly variable in quality. If you can’t find inexpensive cells, you aren’t gaining anything by rebuilding the battery!

Thanks for the guide, it was very helpful when I tackled this one!

Peter

By: ANIL

ANIL — Sat, 24 Apr 2010 10:16:18 +0000

HELLO KEITH DO U HAVE A REPLY OF MY QUESTION. I DID THE SAME AS WRITTEN IN TUTORIALS. THE BATTERY IS NOT GIVING ANY OUTPUT. THOUGH THE INDIVIDUAL CELLS R CHARGED. I DID THE SAME THIN WITH THE OLD BATTERIES IN ORDER TO CONFIRM THE WIRE SETTINGS, THEY MIGHT HAVE BEEN SHOULDRED WRONG,BUT THE OLD BATTERIES ARE GIVING OUT PUT FOR FEW MINUTES. BUT THE IBOOK G4 14 INCH BATTERY WITH NEW CELLS IS NOT GIVIN OUT PUT. NEITHER THE LIGHTS ON THE BATTERY ARE WORKIN. WHEN I CONNECT THE CHARGER ,THE LIGHT ON CHARGER BECOMES ORANGE FROM GREEN BUT WITHIN 3 MINUTES IT BECOMES GREEN. MEANWHILE THE SCREEN SHOWS THE BATTERY INVALID. WHEN THE CHARGER LIGHT IS ORANGE 9charging mode 0 THE LIGHTS ON BATTERY DOES NOT BLINK. I THINK THE SUPPLY IS NOT COMIN OUT OF THE BATTERY IS THERE ANY DIODE OR RESSETTR IN THE BATTERY. REPLY ME.

By: anil

anil — Wed, 21 Apr 2010 11:11:07 +0000

i did same thingh. replaced all 18650 cells(i book g4 14 inch). but the battery is not workin. the individual cells are showing charge in multimeter but is not giving any out put in multimeter. when i connect the adapter the adapter ligt changes from green to red
and on screen the battery icon show 0% and after some time the icon show a multiply sign on the battery icon. tell me why this thing

By: levinson

levinson — Wed, 07 Apr 2010 20:31:26 +0000

A Google search finds this: Lithium-ion batteries age. They only last two to three years, even if they are sitting on a shelf unused. So do not “avoid using” the battery with the thought that the battery pack will last five years.

From the “How Stuff Works” website.

On the other hand, the battery in my Powerbook G4 are still going pretty strong. About 6 years now.

Another website does not speak well for their shelf life, either.

Recycle them, I say.

By: Kevin

Kevin — Wed, 07 Apr 2010 20:17:07 +0000

Keith, you are correct, I do not have a PowerBook to try the batteries in. Anyone else have any thoughts on whether or not two never used and in the box Lithium Ion Powerbook 3400 series batteries would be good enough to use after all these years?

By: Keith Neufeld

Keith Neufeld — Wed, 07 Apr 2010 20:12:04 +0000

Kevin, I would expect the old batteries are not good — I don’t think Li-Ion has that great a shelf life. I take it you don’t have a PowerBook to try them in?