Some pieces of equipment will complain about "low battery" long before the cells which power them are fully discharged.

One use for these "tired" cells is in remote controls or clocks, where they can often give some months of useful further service.

But eventually even these low-duty-cycle low-power devices start to operate intermittently.

Yet the cell is not yet completely discharged; some energy remains.

At last, away of getting those last few picojoules of energy !

We offer the BorgCo electron harvester. It consists of a silver battery clamp with gold-flashed contacts, connected to the electronics, which consist of a high valuue low leakage capacitor connected through a CMOS switch.

An ultra high impedance differential electrometer senses the voltage on the cell terminals, and if it is above the capacitor voltage, opens the CMOS switch and allows energy to flow to the capacitor. When enough energy has accumulated, a second CMOS switch opens and dumps the charge through a pulse transformer and thence into a larger capacitor wich is also ultra low leakage and with a very low ESR.

From this capacitor, some energy is diverted to to power the device itself, and the rest is pulse charged into an alkaline cell to recharge it.

The Harvester only gives up when the input cell is completely and totally dead.

The DeLuxe version has multiple input cell bays which are polled in succession.
-- 8th of 7, Feb 14 2010

Another electron harvester. http://www.emanator.../bigclive/joule.htm
[coprocephalous, Feb 15 2010]

Great idea, but this might be bad for some rechargeables, which do NOT enjoy being fully drained.

I've always thought of a waste silver recovery system (from waste aqueous silver solution) as a use for my almost-dead batteries.
-- cowtamer, Feb 14 2010


Ooooh - good old-fashioned round torch bulbs give me a warm feeling inside. Was the holder one of those white brittle ones?
-- MaxwellBuchanan, Feb 14 2010


oooh - a batten holder. Always puzzled me why they were called batten holders. Were they intended to be fixed in rows along battens in some early strange device? Were they named after a Mrs. Batten, who has mysteriously and unfairly lost her capital B?
-- MaxwellBuchanan, Feb 14 2010


//Were they intended to be fixed in rows along battens //
Not "fixed", but "mounted" - named after Prince Phillip's late uncle.
-- coprocephalous, Feb 15 2010


Ahhhh ... now, at last, it begins to make sense ...
-- 8th of 7, Feb 15 2010


...full of Battenborg cake, no doubt...
-- hippo, Feb 15 2010



random, halfbakery