6 Feb
2016
6 Feb
'16
1:29 p.m.
On Feb 6, 2016, at 4:21 PM, Mark J. Blair <nf6x at
nf6x.net> wrote:
Today I discovered that I hadn't replaced the NiCd battery in time in my Amiga 3000.
Pictures:
...
While I begin to figure out how I'd like to perform this repair, I'm curious
about what others have decided to do in similar circumstances. Many options come to mind:
* Solder in the same kind of NiCd pack to keep things original.
I haven't yet done this, but I have a device (Fluke 881AB voltmeter) with dead NiCd
batteries, and when I get around to replacing them that's what I was thinking of.
NiCd batteries are still available.
* Solder in a supercap instead.
That has vastly less capacity, and a very different discharge curve (exponential vs.
nearly flat). Depending on the circuit using it, that might work slightly (at 10%
capacity, maybe) or not really at all.
* Reconfigure the circuit to use a non-rechargeable
lithium coin cell in a holder instead. I don't think I've seen one of those leak
before.
It hasn't happened to me, but have heard of one case of a leaking Li primary cell.
Not a coin cell, but a C-sized one: I remember a report of one leaking in an automatic
parachute opener (AAD), wrecking the parachute. In fairness, that was one left in quite a
number of years beyond its expiration date. (Before someone asks the obvious: the problem
was found during a required inspection on the ground.)
paul