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PowerBook 3400C Battery Rebuild
Posted by: Powerbook27364 on 2023-10-19 16:52:19 Well, now I have a new item to hunt for and some new hope haha. I'm assuming there is some sort of board inside them that needs to be saved?
Posted by: TonyJay on 2023-10-19 20:12:05 The 3400s can use either NiMH or LiON batteries although AFAIK all were shipped with LiON. Originally 5300s were also shipped with LiON but were recalled due to battery fires- firmware was changed to not allow LiON, only NiMH. So 5300 NiMH packs will be around and there were definitely 3rd party ones (BTI?). The ones I have now are not leaking at least externally, but are good and truly dead. From what I have been able to find, they can be rebuilt. So I am hoping to use them in my 3400's and live with their lower capacity. I am not sure if rebuild is hard but I am having a battery repair shop do them. I recently rebuilt a couple of Newton 2100 NiMH batteries... Now that was a nightmare as the clearance are SO tight that after what seemed to perfect seam gluing, I had to sand the cases almost to the batteries to get them to slide it.
Posted by: 3lectr1cPPC on 2023-10-19 20:16:20 The 5300 battery case style is horrid to open. Possible though.
Posted by: TonyJay on 2023-10-19 20:20:38 I will post progress. Unfortunately battery shop supplier sent the wrong batteries (too big) so I have wait another 3 weeks. Apparently they order all their batteries from one source.. did not ask from where, but likely China. BTW here is 68kmla.org previous discussion on rebuilding 3400 batteries. No success. https://68kmla.org/bb/index.php?threads/powerbook-3400-kanga-battery.39451/
Posted by: LaPorta on 2023-10-19 20:48:42 If you want an in-country supplier, check Batteries Plus. They are where I get my 4/3 A NiMH cells for PB1400 rebuilds.
Posted by: 3lectr1cPPC on 2023-10-19 20:49:50 Do you go in person or on their website? I’m going to need to order some for my 3 packs at some point.
Posted by: LaPorta on 2023-10-19 20:52:08 I'm fortunate to have a local branch, but you can order online as well. The benefit of going in person if you have a store nearby is they will actually tack-weld on metal tabs in the places that the original battery pack has them if you give them the old one as an example. This will greatly simplify your rebuild.
Posted by: 3lectr1cPPC on 2023-10-19 20:53:25 do you solder yours? My plan is to get a spot welder to do it the “proper way”, although if you’re careful then soldering’s fine. I think there’s one near me. Is batteries plus bulbs the same?
Posted by: LaPorta on 2023-10-19 21:01:32 I have them tack-weld on tabs, and then I solder the tabs to bits of the old ones. I really should get the welder as well, but it worked ok for me. Here is how the packs looked side-by-side. You can see the tabs they put on with some length. I trimmed them up and then soldered as necessary in the second photo. One more important thing I ran into: make sure that the cells DO NOT have the protruding nubs from the positive side. If they do, the cells will not fit inside the battery case. They need the flat positive and negative ends.
Posted by: TonyJay on 2023-10-19 21:32:15 I have them tack-weld on tabs, and then I solder the tabs to bits of the old ones. I really should get the welder as well, but it worked ok for me. Here is how the packs looked side-by-side. You can see the tabs they put on with some length. I trimmed them up and then soldered as necessary in the second photo. One more important thing I ran into: make sure that the cells DO NOT have the protruding nubs from the positive side. If they do, the cells will not fit inside the battery case. They need the flat positive and negative ends. View attachment 63856 View attachment 63857 The 'nub' issue is an important one as cases often do not have any clearance. I rebuilt a PB 145b battery but had to send back the batteries initially sent. They listed as 'flat' as they were not truly flat. Company was good about it and found truly flat NiMH for me. For that matter, AA battery diameters can be different - companies should list the full specs for any battery as nothing screams frustration better than a glued case that won't slide into the device, because it is very slightly bulged (aka my Newton 2100 battery rebuilds).
Posted by: croissantking on 2025-05-04 01:09:22 Any updates in 2025? I have two batteries I’d like to rebuild but reading this thread and the other one it doesn’t sound hopeful.
Posted by: LaPorta on 2025-05-04 11:47:00 These still work well long-term for the 1400.
Posted by: croissantking on 2025-05-04 12:05:27 These still work well long-term for the 1400. But this thread is about the 3400c, which is the machine I’m referring to.
Posted by: LaPorta on 2025-05-04 14:07:13 But this thread is about the 3400c, which is the machine I’m referring to. My apologies. Seeing all my posts, I thought it was a parallel 1400 thread that is out there.
Posted by: macdude888 on 2025-05-16 09:53:01 Good luck. I have read that some have tried to prevent the BMS from bricking itself by maintaining power using external power, but did not work. Should have... but did not. Not sure why Apple did this, as other LiON models can be rebuilt. I have a couple of NiMH packs for 3400 waiting to be rebuilt but they take 12 pcs HR-4/3AU NiMH cells that are twice as expensive in comparison to regular 18650 LiON cells. And of course they have to be ordered and not kept in stock. Good I can hurry up and wait. 🙂 Hey there. So what ever happened? Were you able to get working 3400 batteries again?
Posted by: mkinn on 2025-11-02 21:32:56 I have a 3400C coming in the mail with a barely alive battery, and want to know if there’s a way to rebuild them currently? If not, is there places where I can find NOS batteries that still work? Does ANYBODY have a pinout/wiring diagram for the 3400c battery? I'd like to try rebuilding one.
Posted by: croissantking on 2025-11-03 00:53:08 Does ANYBODY have a pinout/wiring diagram for the 3400c battery? I'd like to try rebuilding one. Not sure what sort of diagram you mean, but I don’t think there is such a thing out there. If you mean just for the cells then it’s pretty obvious how to wire things up once you get the battery pack open. 🙂 Be aware that others have tried to rebuild this battery and the BMS always gets bricked as soon as the old cells are disconnected. Unless you’re planning something special to work around this, it may not be worth the hassle.
Posted by: 3lectr1cPPC on 2025-11-03 14:39:13 I'd just recommend rebuilding a 5300 battery instead. They work in the 3400c, although wouldn't give as long of a runtime as the Lithium battery would have when new.
Posted by: croissantking on 2025-11-03 16:28:45 They work in the 3400c Is this confirmed? I tried a 5300 battery in a 3400c and it wasn’t detected.
Posted by: 3lectr1cPPC on 2025-11-03 16:29:42 Weird. That's definitely confirmed.
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