On Tue, 13 Dec 2011 19:45:07 -0800, Jeff Liebermann
wrote:

On Tue, 13 Dec 2011 05:13:46 -0800, "William Sommerwerck"
wrote:
The cells are Sanyo Superlattice Alloy EVO, model HR-3U. They were not
shipped pre-charged, and as far as I can tell, they are not
slow-self-discharge ("eneloop") cells. The Sanyo USA site has no information
about them. However, they are available from Batteries America. (Thomas
Distributing doesn't list them.)

This might be of interest:
http://www.stefanv.com/electronics/sanyo_eneloop.html
It's an independent test of the Sanyo Eneloop NiMH batteries including
some self-discharge tests. Unfortunately, he doesn't compare the
results with the non-LSD batteries. Scroll down to the "Self
Discharge" section heading and note the self-discharge tables.
50% charge loss after 1 year.

There is also this quote from Sanyo:
Storage temperature is of high importance if you measure
self-discharge rate. Higher temperatures substantially
increase self-discharging. It is best to store Eneloops
as cool as possible to keep the charge in the battery.
As a rule-of-thumb, every 10°C increase in storage
temperature is equivalent to doubling the storage time.
Some R/C pilots in Europe put Eneloops in the freezer,
with rather good results.
So, how were your batteries stored?

Presumably, the non-LSD batteries would produce much worse results,
making your miraculous Sanyo HR-3U cells better than Eneloop cells,
which seems rather dubious. Since the Eneloop batteries tested were
brand new, I don't think it's something related to an aging effect.
That leaves your test as an oddity. Are you sure someone didn't
charge your batteries when nobody was looking?

In for a penny's worth; i add that this might be some freaky low self
discharge cells for the given process, perhaps at some process corner for
the set.

?-)