Macintosh PowerBook 145/160/170 battery replacement

[Westinghouse]

Glad to hear it's working out okay - I was a little worried that some tweaks I made to the external contact area on the battery might have messed up the spacing.

People always seem to be more interested in 3D printers when they see an example of how they can print replacement / repair parts instead of just trinkets & doodads. I'm sure everyone's been in a position where a broken part just isn't worth replacing, if indeed possible to replace.

The first thing I modeled up for printing was a tiny retaining ring for the shutter release of a vintage camera - the only other way to replace it would be to buy another whole camera, or machine a new piece.

 

[Rajel]

So, I had the machine booted up with the SCSI2SD last night, ran like a champ.
Didn't even come close to draining the battery before shutting down for the night.
Booted it up this morning, and it appears the battery has almost completely drained - anyone else see this behavior? I'd think there shouldn't be power drain while the system is shut off.

 

[zuctronic]

Maybe it's trying to charge a dead PRAM battery? I actually have a similar issue. I also wonder at what voltage level does it force sleep / shutdown. I have a rebuilt batpack with 10 cells in it and this new printed one with 5 cells and neither seem to last as long as I'd expect.

 

[Rajel]

My first thought was PRAM battery. I'm running 6 in the printed pack (the system regulates battery output anyway) and while running last night I never saw the meter level drop at all.
I do need to swap the PRAM battery anyway, guess that'll be the next fix.

 

[zuctronic]

Hmm... I know I can fit 6 cells in there, but it seems a bit ill-advised - I don't know enough about the voltage regulator. Are you sure that won't burn anything out? I'm completely ignorant in this area, I'm just afraid of destroying something that's difficult to repair.

I have the opposite problem though, the voltage drops down to "two bars" very quickly and then hangs there for about an hour before it dies hard.

 

[Rajel]

Well, the PSU itself is 7.5v/2A. The system doesn't run at that voltage/current, it's regulated down. Same for the "6v" from the stock battery. Battery voltage fluctuates enough that good regulation is required. Most can handle a decently wide range; not sure what the PB160's battery regulator maxes at, but I've had no ill effects other than the system overall getting slightly warm - not anywhere near as warm as my G4 gets, but you'd want to have this on your lap on a cold night.
I could install a switching DC-DC convertor to give it a steady 6V out, but the issue then is more wasted energy from the conversion as it's a two-step process now, when it could be done with just the one. My friendly engineer buddy assured me that 6 cells in the pack was rather safe.
Worst case, I'll pin down the regulator coming off the battery inputs, and work out a swap for something more efficient which would reduce heat *and* extend battery life slightly.
...heck that actually sounds like a good idea, might do that anyway.

 

[zuctronic]

Ah, your explanation makes perfect sense and makes me feel a lot more comfortable about using six cells. Did you also take the klixon from the original battery pack?

 

[Rajel]

Nope, I'm actually just running straight battery. I had a fuse on it but then realized that the fuse itself actually shorted the back (which probably just blew immediately)

 

[Rajel]

The protection really isn't as needed unless you're charging the cells from the PB itself, and right now I just charge them individually in the Eneloop's included charger.

 

[zuctronic]

I see. But also if the only way these PBs know the charge level is via the voltage output, it might not charge 6 cells properly or fully anyway - right?

 

[Rajel]

Also probably true. Generally, I'm probably going to stick to external charging for the individual cells.

 

[Rajel]

I have the opposite problem though, the voltage drops down to "two bars" very quickly and then hangs there for about an hour before it dies hard.

And this is actually something of an issue with these rebuilt packs - NiMH cells hold voltage pretty well, the voltage drop is really slow for most of the runtime, and then it drops very sharply.

Basically, the metering is pretty much useless.

 

[Westinghouse]

Techknight, I came across a mention of putting a resistor between two pins in another of your posts on the subject.

https://68kmla.org/forums/index.php?/topic/27875-portable-is-driving-me-crazy/?p=297998

Wondering if you remember which two pins?

 

[nvdeynde]

I've also recelled several battery packs with 5x Panasonic HHR380A 4/3 Nimh Cells of 3800 Mah each.

The issue I'm having with my PB140,145,145B,160 is that the powerbook stops charging at almost exactly 2 hours with the original 2A PSU ( recapped as well ), so it's impossible that the batteries are fully charged. They don't last long as well, with everything ON ( led, hdd, backlight ) I get 1.5 hours of battery life at most.
The original Apple battery pack was build with Nicad batteries and had a total capacity of just 2400 mah.

I'm wondering if other members here have similar issues.

In the Apple developper guides it says the powerbook 140 charges it's battery for 80% in 2 to 3 hours and then adds another 3 hours to trickle the remaining 20%, so that gives a total charge time of over 5 hours at least.

The Panasonic batteries are not the problem, 100% sure, neither is the PSU as it's spot on at 7.5 Volts 2A.

What's the capacity of the cells you used to rebuild the battery pack and how long does the powerbook charge them until the battery indicator says they are full ?
How much running time you get with everything on after fully charged ?

 

[PB170]

Just thought I'd join in and add that I made a first, and successful attempt at building a new battery for my PowerBook 170 at the beginning of this year. I don't have access to any 3D printer so I made the case using saved pieces of translucent plastic that melted together using an iron with a layer of aluminum foil in between.

The battery itself consists of 10 NiMH cells (gen 2) of 2600 mAh each (in a 2 x 5 arrangement like the original batteries) giving a total of 5200 mAh.

I get around 5.5 hours of usage out of it under normal load (in practice almost a threefold increase over the original batteries' capacity!).

I've also upgraded the display to LED backlighting (more about that in a separate thread later) which radically decreased the backlight's power consumption (unlike the previous upgrade to CF storage, which according to my measurements consumes about the same as the original hard drive).

I had planned to add a switch to be able to use the battery without constantly charging it, but decided not to in order to avoid the unnecessary resistance. Instead, I duplicated the indent in the side of the case so that I can flip the battery backwards inside the computer.

I also added a DC connector port to be able to charge it externally (not in the photos below).

If I make another one I'll probably try to use the original cases.

 

[Johnnya101]

EXCELLENT JOB!

You should start selling these!!! I love the clear plastic look.

 

[Rajel]

Daaaaaaang, that's nice.
I'm interested in the LED mod and how well it works. My 160 could probably benefit from that - I get about 3 hours on 5 NiMH cells as it is. Actually running a NiCd battery back in it now, got a NOS third-party battery and was able to recover a decent bit of capacity, it lasts about 2 hours but at least I can charge it in-system.

 

[Byrd]

Daaaaaaang, that's nice.

I'm interested in the LED mod and how well it works. 

Me too +++, I'd love to see what you've done and if it improves things such as vignetting on active displays.  Please post up a new thread on this!

 

[Rajel]

Me too +++, I'd love to see what you've done and if it improves things such as vignetting on active displays.  Please post up a new thread on this!

It should have no effect on vignetting, that's a known moisture issue. Changing the light source won't help unfortunately.

 

[PB170]

Thanks!

 
I love any application of frosted glass or plastic myself, so that was a natural choice If I would start selling these, I'd have to improve on the build quality and the time spent But I hope my report might be of use.
 
Regarding the LED upgrade, for now I can tell that it works perfectly. With a bit of extra circuity, it maps precisely to the hardware/software controls, and the backlight is very even, with a maximum light output of a little over 400 cd/m2 (for comparison, the original CCFL gave about about 50 cd/m2 when I got it back in 2001 which slowly decreased, until it finally gave up in 2015). When I find the time (will likely take a while), I will post a more detailed report in these two threads: 
 
https://68kmla.org/forums/index.php?/topic/24371-request-for-information-about-the-powerbook-170-inverter-board-and-led-upgrade/
https://forums.macrumors.com/threads/request-for-information-about-the-powerbook-170-inverter-board-and-led-upgrade.1832944/
 
By the way, Rajel, I saw your post in the thread about replacement CCFL bulbs, where you mentioned that LEDs will give an uneven backlight with old panels made for CCFLs. This is not the case at all with my PowerBook 170, where the backlight is completely even. However, I noticed while taking apart the backlight on a PowerBook 140 that I use for spare parts, that its optical system is different from the 170's. While the backlight of the 170 consists of a reflector sheet, a light guide plate and two frosted diffuser films, the backlight of the 140 has only a reflector sheet, a light guide plate (with the pattern facing the reflector instead of the LCD like in the 170) and a simple milk-white diffuser sheet (absorbing a lot of light in comparison with the two diffusor films of the 170), so the type of optical system might be a factor.