To charge a pair of ideal rechargeable AA cells (2.5Ah 1.2v) this would take 6000 hours, or 250 days.

Pod to hold six AA cells (three on other side).

Battery pods containing groups of AA cells have been used in vast numbers by nearly all detector manufacturers for many years.

Batteries, however, are not included: six AA cells are required.

A typical AA cell has roughly 1 ampere-hour of charge.

Probably three AA cells will just run it.

An easy fix for replacement batteries is to use four AA cells in a holder secured on the inside.

Ovonics is now working on AA cells, the most widely used battery size.

The circuit was powered by a single AA cell; the battery life was stated to be over 6 months.

If this company has a process that's similarly cheap relative to manufacturing the AA cells they're making a comparison to, perhaps they can be competitive.