Lifetime of VAX NiCd packs?

From: Richard Erlacher <>
Date: Sun Dec 24 00:31:15 2000

First of all, you've gotta know that I know nothing about the machine in
question, except that folks have learned a good deal about NiCd batteries
since those were designed into the DEC application. Allison's right on the
money with her proposal of discharging a hefty charge through a
"grown-short" in the battery. The charger design I've liked best so far is
one that uses a series capacitor rather than a resistor or whatever in
series with the AC to charge the battery in a way that won't support the
presence of those cillia that eventually short the cells.

I built a switched constant-current sink to charge several batteries at
once, with an average current equal to the maximum that the battery is
supposed to source, but at a 10% duty cycle and 10 KHz. It's being compared
right now by the guy who built the one with the cap just to see which one
provides better results. The CAP design is MUCH simpler.

----- Original Message -----
From: "Chuck McManis" <>
To: <>
Sent: Saturday, December 23, 2000 9:25 PM
Subject: Lifetime of VAX NiCd packs?

> Does anyone know the approximate lifetime of the NiCd battery on a VAX
> it isn't turned on all the time? I've got several dead ones and it is
> irritating to set the language and boot device every time. I've tried
> "zapping" them, this brought one back but the other is quite dead. I've
> almost have enough to put together one get pack from cells in the bad ones
> --Chuck
Received on Sun Dec 24 2000 - 00:31:15 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:32:50 BST