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Macintosh PowerBook 145/160/170 battery replacement
Posted by: Ferrix97 on 2015-03-03 03:38:29 Hi! Yesterday I tried using a battery pack from a broken (dead GPU) HP DV9000 to power a PowerBook, using one of those cheap DC-DC Step-Down modules. The battery supplied about 15.5 Volts, the module's output was set to 6.8 Volts and was plugged into the DC Jack of the PowerBook. With a powerbook 145 hooked to the circuit I was pulling about 0.5 Amps from the battery and about 1 Amp from the module, which is rated for 2A. I made those measurement while playing Glider, so the hard drive was kept on and the processor was not sleeping. The floppy drive was not in use. The heat was not a major problem, the module got slightly hot, but nothing too dangerous. I later stuck an old Heatsink, that made the module cooler, ideal for a closed enclosure. At this point, I opened the battery and found 8 18650 batteries, 4 pairs in parallel. I could take off a pair or two, making the voltage lower, (about 8 Volts) and mount the batteries together with the DC-DC module inside a dead battery. I know that I can't recharge from the computer, but I can use one of those RC Planes/cars chargers. at the moment I am using the computer to charge the battery. do you think this is doable?
Posted by: Elfen on 2015-03-03 08:41:01 Those RC Battery chargers can charge in Slow and Fast charging modes. Best to use it in slow mode and check the progress of the battery as it charges. In Slow mode, it takes a couple of hours to charge and on Fast mode 15 minutes or so. In Fast mode it is normal for a battery pack to get very hot. This might be dangerous for the laptop pack so I won't recommend it. It also shortens the battery life and the number of times you can charge it. I have seen NiCad packs burst then charged too much on Fast mode. In Slow mode, the battery should get warm if at all. You just have have to monitor it and see how it goes.
Posted by: Ferrix97 on 2015-03-03 11:02:28 Thanks for your help, I think (if the project ends up working) I will use one of those intelligent chargers I know that I can't recharge from the computer, but I can use one of those RC Planes/cars chargers. at the moment I am using the computer to charge the battery. Correction: "I know that I can't recharge the battery from the PowerBook, but I can use one of those RC Planes/cars chargers. at the moment I am using the DV9000 to charge the battery." That is the main reason for keeping the entire battery pack intact, so I can use the charger/maintenance circuitry of the DV9000 laptop.
Posted by: techknight on 2015-03-03 15:50:23 You can recharge the lithium batteries from the computer IF... You get a lithium ion charge controller/monitor circuit, and set the circuit up for the number of cells/voltages your using. it has active FET switching networks to detect if your inputting voltage. if not, it switches them on to allow voltage to pass back out to the load. Here is an example of such a circuit: http://www.batteryspace.com/pcbfor148vli-ionbatterypack5alimitwithfuelguagesocket.aspx They are universal, This one is setup for 14.8. you would need to get one for your battery voltage, to match that of your charging voltage/current.
Posted by: Bunsen on 2015-03-03 19:50:55 The battery supplied about 15.5 Volts, the module's output was set to 6.8 Volts and was plugged into the DC Jack of the PowerBook. The original PS for those is 7.5V, correct? I opened the battery and found 8 18650 batteries, 4 pairs in parallel. I could take off a pair or two, making the voltage lower, (about 8 Volts) Divide the pack in half and you should have about 7.75V. I would be willing to bet you can run that straight into the DC jack without a stepdown. Then you could have either two interchangeable packs (charge one while using the other), or a single pack with double the capacity (running pairs of 2 cells in parallel, then the pairs hooked up in series to equal 7.75V) and mount the batteries together with the DC-DC module inside a dead battery. Inside a dead Powerbook 1x0 battery, so you can use it as an internal? IDK that I would recommend that ... the PB will attempt to charge the battery while it's plugged in, and that could be ... not good. Even if you can disable that, I don't like the idea of having an experimental DIY lithium pack inside an antique Powerbook. If anything goes wrong, you risk losing both of them (kaboomph). For safety's sake - and for heatsinking - it might be best to have the new battery pack external and going into the DC jack as you have now. If I was going that way I might look at using brand new LiPolys with per-cell protection circuits. You can buy them built in. Or you could use the battery bay to hold the new pack, but run a cable round the outside to the DC socket, and not hook up to the internal connections at all. If you do decide to build it as a real internally connected pack, you would want to match the voltage of the original battery pack exactly, for starters.
Posted by: uniserver on 2015-05-19 02:52:44 Anyone tried to wire up some nickel metal AA batteries yet? I just got a killer 170 from Ted and I want to give it some battery life
Posted by: uniserver on 2015-05-19 03:04:02 http://pages.ebay.com/link/?nav=item.view&alt=web&id=301035799704 Or maybe 4 of these? Might fit?
Posted by: Ferrix97 on 2015-05-19 04:02:59 It should be doable. next time I will crack open another battery pack I will post some photos regarding the size and placement of the cells. Once school finishes I will get back to this project.
Posted by: 4seasonphoto on 2015-05-23 09:59:59 Anyone tried to wire up some nickel metal AA batteries yet? I just got a killer 170 from Ted and I want to give it some battery life No need to DIY this: replacement NiMH packs for PB1xx are still available at okay prices. I'd expect them to work fine but maybe would take care not to leave them charging longer than necessary: I seem to recall that overcharging will shorten the life of NiMH batteries. Been awhile since I cracked open an original Apple battery but seem to recall seeing a string of flat-top solder-tab (2/3 A? 4/3 A?) cells wired in series with some additional small device in there, perhaps a self-resetting breaker. Wanted to reuse the battery case from my current PB180 but it had toxic yellow goo all over it
Posted by: Ferrix97 on 2015-05-23 10:34:06 Just opened a dead pack, it consists of 10 cells and a couple of sensors. It looks like the cells are in series. they are slightly smaller that a regular AA, way smaller than an 18650. once I finish with school I will get beck to this project. in the meantime I've ordered some extra components to make it safer to use
Posted by: Ferrix97 on 2015-08-12 10:02:38 Here is the first prototype I tried it on several powerbooks and it works perfectly! I added a 2A Fuse on the battery output to protect the DC-DC Converter and the PowerBook in case of a problem. I also need to add a battery cell monitor, to make sure that the cell voltages don't go too low. Right now I am still using the laptop for charging the battery and it is working fine. This should also work in a Macintosh Portable, you can fit it into the battery bay quite easily, But of course, you can't recharge the pack from the Portable. The highest temperature I measured was about 65°C, next time I will use a beefier DC-DC module with better heatsinking
Posted by: techknight on 2015-08-12 15:33:07 You cant properly recharge that pack at all, if you removed any cells. If you have, you have to reprogram the controller for the correct # of cells/voltage.
Posted by: scruss on 2016-12-16 07:23:02 What size of barrel connector does the PB use? I have a couple (a 140, a 170) with no power supplies. No batteries, either, and it doesn't look too hard a shape to 3D print for new cells and sensors Nice work on the replacement circuit!
Posted by: Ferrix97 on 2016-12-16 08:26:05 The connector is the usual one (with the smaller center pin). 3D printing a new battery case should be fairly straightforward. It's on my projects list. An ideal solution would be a case that can be easily opened an closed (something like a hinge on the opposite side of the battery door, remove the battery, slide out the door and it hinges open) with easy to remove AA batteries inside, maybe eneloops with a long shelf life. (since I plan to use it on batteries maybe 3 or 4 times a year)
Posted by: scruss on 2016-12-16 18:46:51 There are many DC connector sizes, including: Type A: 5.5 mm OD, 2.1 mm ID Type A: 5.5 mm OD, 2.5 mm ID Type B: 6.0 mm OD, 2.1 mm ID Type B: 6.0 mm OD, 2.5 mm ID Type C: 3.8 mm OD, 1.4 mm ID Type D: 6.3 mm OD, 3.1 mm ID Type E: 3.4 mm OD, 1.3 mm ID so I'm not sure what you mean by "the usual one". With modern NiMH cells, you could get pretty close to the original capacity with five (ish) AAs. I don't think I'd want to risk LiPo, as they have very special charging needs
Posted by: scruss on 2016-12-17 17:46:23 ah, sorry; got what you meant. Looks like a Type A, and that's what my 140 is now powered with. Thanks!
Posted by: Westinghouse on 2017-01-16 20:58:19 Thanks for the images in this thread! I was looking to build a new battery for my 140, and the information here was very helpful; there aren't a lot of photos of the innards of a 1X0-series battery around on the internet.
Posted by: Westinghouse on 2017-01-19 16:33:29 Taking a crack at printing up a replacement battery tray on the local library's 3D printer right now.
Posted by: scruss on 2017-01-25 05:00:06 Is that battery tray your own design, Westinghouse? It looks very neat. Can you share it, please?
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