Date   : Thu, 18 Jan 2007 15:59:52 +0000
From   : adsb@... (Andrew Benham)
Subject: Batteries in a Master

Jules Richardson wrote:

> I'd always assumed it was just discourage users from randomly replacing 
> batteries - mixing types and/or different levels of charge can probably make 
> some batteries a little upset and prone to leakage.

Nope, more than that.

The original Acorn design used a rechargeable lithium cell, with a timer
circuit to limit the charging.

Recharging lithium cells, at least in the 1980s, could have unfortunate
results.  One of my colleagues at the time had previously tried
recharging a lithium cell which he was thinking of using in a product.
Because he'd read that it could go wrong, he'd put the cell in a bell
jar in the lab, and then left for the evening.

Luckily this was in a different lab from mine.

It blew the windows out of the lab, and the glass knob on the top of the
bell jar was embedded in the ceiling.

-- 
Andrew Benham           adsb@...       
Southgate, London N14, United Kingdom

The gates in my computer are AND OR and NOT, not "Bill".