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Powerbook 5300c Battery Rebuild (sorta)

raoulduke

Well-known member
There are two resultant problems.  1) OS 9 (probably all the OS's) doesn't really recognize the battery (charge time remaining etc.) so I'm concerned it may not have the charge/discharge division totally right.  2) It gets surprisingly hot - the batteries themselves it seems, mostly.  I've left it in a few hours with the Kanga on, in fairness.  Still I didn't think the Klixon thermistor was really necessary until I felt the case.  I have no great estimate but maybe 100-120 F.  The thermistor is supposed to break the circuit (I think) at either 140 or 150 (70 or 75 C) - I forget which one I left attached.

I've actually confirmed that first part.  When I unplug it, OS 9 shows the battery life go from 4:55 to 1:50 over the course of about 30 seconds.  Then it goes up to about 2:55 and sort of hovers around that level.  I'm going to leave it plugged in overnight assuming it doesn't heat up as much while not on, but that is potentially problematic - that I can't know the battery level.  Maybe the 5300 will do better with it.

 
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raoulduke

Well-known member
Or actually those centigrade estimates are off (170-180)

I just got a bunch more 3400c li-ions including one that may actually work well, so I'll probably relegate this to a 5300x.

 
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raoulduke

Well-known member
Finally, the 5300c NiMH I rebuilt only seems to hold a charge for a few minutes - after several chunks of several hours of charging (separately - I know that's bad).  The only thing I can think of at this point is that I've ruined the batteries over the course of these trials.

I'll swap in the 8 new batteries I have, and if that solves the problem perhaps that's a test of whether I've killed the cells.

 
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raoulduke

Well-known member
(The new 8 didn't really help.  Battery Amnesia got 8 minutes the first time; I fell asleep after about 10 or 15 minutes the second time.  But the life isn't good.  I'm giving up.  Mouser just shipped the (li-ion) 26650 battery holders for the 3400c batteries.)

 
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