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Warning! Exploding Maxell PRAM Batteries

James1095

Well-known member
Those caps are shot anyway, you can see the leaked electrolyte, the corrosion is why those parts fell off in the first place, look at how black that solder looks. Even if it was well packed, it would still need to be repaired.

Any board you find will need to be re-capped, so if you can't solder yourself, you'll have to have someone else re-cap the board for you. Those old SMT electrolytics just don't last very well, the old ones have all dried out or started leaking. This particular board looks like an easy fix, just clean it up, re-cap and solder that oscillator back on.

 

max1zzz

Well-known member
Looking at the chip it's not just as easy as soldering it back on, it has taken 3 of the 4 pads off with it...

That said, it should be repairable, just need to track the traces back to a another chip, or somewhere easy to solder and then run a wire

Things like this always remind me of the xbox i had shipped to me that was litterley wrapped in some cereal box cardboard and a layer of the thinnest bubblewrap i have ever seen... amazingly that still worked (well, sorta...)

 

volvo242gt

Well-known member
Looking at the chip it's not just as easy as soldering it back on, it has taken 3 of the 4 pads off with it...That said, it should be repairable, just need to track the traces back to a another chip, or somewhere easy to solder and then run a wire

Things like this always remind me of the xbox i had shipped to me that was litterley wrapped in some cereal box cardboard and a layer of the thinnest bubblewrap i have ever seen... amazingly that still worked (well, sorta...)
Recently had something similar happen. Won a Sony receiver off eBay. Got it for $34, plus the $42.90 shipping. A week or so later, I receive a box that looks like it has been jumped on. Open it up, and discover the receiver at the bottom of the box with a cardboard box flap being used as "packing material". The lid has an "outie" dent on the side, there's a chunk of plastic missing from the side of the front panel, and the front panel is loose at the top. Surprisingly enough, everything works on it. So, I'm using it. I should've filed a claim with PayPal after the guy denied any wrongdoing... But, oh well. Now on the search for a dead STR-GX6ESII to pilfer the lid and the front panel parts from.

-J

 

NickNick

Well-known member
Those poor Macintoshes...I went through all my Macintoshes and pulled all the batterys out, Even the square ones that were in my Performa 631cd and Power Mac 5500/225. Both seemed ok but the one in the Power Mac seemed to be buldging. Seems I pulled it in the nic of time thanx to these posts and pictures. Someone was inquiring about the square ones so I thought I'd share what I found. I was lucky as none of my machines had any leaking batterys yet. I have also yet to find one maxell in my machines. Mostly the purple and blue ones in all my pizza box macs.

Qurious...once this has happened to those machines, has anyone had any luck bringing them back to life after the batterys go bad all over? The reason I ask is from time to time you see pizza box macs that had a battery eplode in them. I was wondering if they are reversable.

Nick.

 

CC_333

Well-known member
Before I knew what I now know, I pulled apart my first 68k Mac (an SE/30 from 2005), and found that the battery had leaked. I removed it and put it in a plastic drawer. I still have it, actually, and the whole drawer's a big mess. I really am glad that's not a computer!

I'd post a picture, but I think we've all seen enough atrocities for now.

c

 

Scott Baret

Well-known member
Just worked on a Classic for a guy referred to me by one of the Mac user group leaders in the area.

Inside his Classic was a Maxell. No leakage yet, but I'll be darned if it didn't have "I'm gonna corrode your board really soon" written all over it. Needless to say, it was removed right away. I'm almost positive this particular one was as old as the Classic itself, which was 23 years old and still being used as this guy's main computer.

 

CC_333

Well-known member
...which was 23 years old and still being used as this guy's main computer.
That's bizarre! :lol:
How can anyone use a Mac Classic (or, for that matter, any 68k or early PPC Mac) as a main computer in this day and age?

Why doesn't he upgrade to a Classic II or SE/30? :eek:)

c

 

uniserver

Well-known member
my boss said that he has friends and knows of other people that live way out in the sticks, they still use old computers and dial up to AOL, with their 14.4's and 28.8's

so that sounds about right lol.

 

MinerAl

Well-known member
Should the title of this thread maybe be changed to Warning! Exploding Old PRAM Batteries?

It's been pretty conclusively shown that, although Maxells may be particularly prone, all old PRAM batteries are ticking time bombs.

I'd hate somebody to pop open their LCIII (or whatever) see a 20 year old green & purple, or blue, or white battery in there and think "whew, at least it isn't a red Maxell; I'm safe."

 

volvo242gt

Well-known member
Or a black Varta... That said, at least, when it came to a certain SE, the original Varta was still showing full voltage.

Just replace the batteries every 5-10 years, and you should be ok. That, or replace the PRAM battery holder with a pair of wires going to a triple AA holder. Plop some NiMH rechargeables in there, and call it good.

-J

 

Ike

Well-known member
Has anyone ever had the 4.5 volt battery (found in e.g. the Power Macintosh 4400) explode or leak? I just removed mine to be sure.

 

volvo242gt

Well-known member
If it's lithium, which I suspect it is, it probably will eventually do so. Hmmm, wonder if that battery could be adapted to a Mac Plus, since the original 4.5 volt alkaline Eveready #523 batteries are almost impossible to find these days.

-J

 

techknight

Well-known member
The ones you do find, are actual "hacks" using button cells or something of the like, and a homebrew wrap to make that particular battery.

 

xboxown

Well-known member
Ppphhewww...good thing apple //gs do not have to worry about leaking battery! Since they don't have one! Phhew!

 

PB145B

Well-known member
You won’t see it immediately when you pull the cover off, because you also have to take the power supply out to see it.

 

xboxown

Well-known member
I wanted to ask about replacing the Apple //gs and Mac LC III batteries with no leaking and explosive ones. Are there safe batteries that I can replace for the Apple //gs and mac lc III that I don't have to worry about them leaking or exploding? What advice can you help in this?

One other question, does the mac lc III really need the battery? Can I do without it? 

 
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