On 2016-08-16, Dave Plowman (News) wrote:
Alan Braggins wrote:
http://www.sheldonbrown.com/dynohubs.html has a illustration of that from
a 1952 Sturmey Archer catalogue, and also describes use of a bridge
rectifier to charge NiCds from a dynamo, the battery also acting as
regulation for the dynamo output.

Think that's wrong. The rectifier acted as a one way valve to prevent the
batteries discharging into the alternator when stopped. The batteries were
dry cells.
[...]
I don't think Ni-Cads were around in 1952 - at least at a price a cyclist
would pay for.

The 1952 illustration is labelled "Dry battery unit". The use of "a 6 volt
(5 x 1.2v cell) nickel cadmium battery", also described on the same page,
is not from 1952.