Battery vampire???

[unclearty]

Any new lights...or buildable circuits to suck the life out of used AA or AAA batteries? Have built a number of the Battery Vampire circuits where you wind your own coil...just seeing if anything new is out there.

 

[Lynx_Arc]

I recently saw a thread where you can buy a kit with a circuit board and parts to make your own.
There is also Voltvamp ones I've seen for sale at times that look pretty good.
With low to very low modes on my 18650 lights and rechargeables I see no need to waste time eeking out a few hundred millampere hours of power from spent alkaleaks when for a fraction of a penny I can recharge an eneloop a lot more than that amount of power and not have to risk cleaning up after a vomiting cell.

 

[unclearty]

I have a situation at work where I get about 6 AA batteries every week that are only slightly drained. I like the idea of a simple low output light for bathrooms at night.
Do you know who had the KITS available? I'm having no luck using SEARCH

 

[LRJ88]

I have a situation at work where I get about 6 AA batteries every week that are only slightly drained. I like the idea of a simple low output light for bathrooms at night.
Do you know who had the KITS available? I'm having no luck using SEARCH

How low do you want it to go? An old Minimag on 2 AA and a 3mm 3V LED will suck out a lot of power and give enough light at night, or an old Maglite 2D with an 8mm LED and AA to D adapters, although chances are with both of these that you'll get enough light but not use up the batteries. I had a Minimag running with just a generic 3mm white LED for a year before i opened it and saw corrosion on the batteries, and the batteries were still far from drained then.

 

[unclearty]

I was hoping for a little circuit that used 1 AA or AA at a time...low output....looking more for runtime as opposed to brightness. I stick these in my bathroom window sills.....prevents having to turn on lights in the middle of the night.

 

[jabe1]

Have you tried a Google search for "joule thief kit"?

 

[unclearty]

Already have 5 or 6 of them....simply looking for something "New...and Improved"

 

[Lynx_Arc]

Already have 5 or 6 of them....simply looking for something "New...and Improved"

I think just about the only noticeable improvement would be LED based as the circuitry and components likely haven't changed that much.

 

[jabe1]

Wquiles made some solid state joule thiefs a few years back. I know there are a few threads about them...

 

[thermal guy]

I use a Voltvamp I got on here every night actually it's on 24/7 to burn through my cells. It's fantastic.

 

[unclearty]

Are these available anywhere...even one?

 

[Dave_H]

I was hoping for a little circuit that used 1 AA or AA at a time...low output....looking more for runtime as opposed to brightness. I stick these in my bathroom window sills.....prevents having to turn on lights in the middle of the night.

As for the "why bother with alkaleaks...not worth it...for a fraction of a penny... etc." that argument's been heard before. Some people want to run down their old alkalines, and some don't. At least it's giving them some usefulness before they (hopefully) go to recycle. And some people have fun doing it.

See this thread (which I started):

https://www.candlepowerforums.com/vb/showthread.php?473112-reclaiming-alkaline-(and-other)-cells

I use solar garden lights, among other devices, to run down alkalines. Some are better than others for low-cutoff voltage. You could try various ones, given that they can be obtained cheaply. Most should be good down to 0.9v at least; one I'm looking at is sitting at 0.65v and still lit.

I found an older amber LED light built using discrete parts (transistors) before the 4-pin ICs or COB drivers became popular. This one runs cell down below 0.5v. Keep an eye out for these, sometimes find them in 2nd-hand stores cheap. I also like amber as alternative to cold white.

The most practical lights have a battery hatch, rather than having to take it apart. Remove the base and clear lens, and flip over; simple. On/off switch is a bonus, otherwise just pop the cell out when not using.

Alternative to single-cell rundown is to use a small light which runs from multiple cells. Match cells for approximately same voltage. Use colour with low forward voltage: red, yellow, amber and some greens. I like green, have such a light and it runs sometimes dozens of hours on 4xAAA down to about 0.5v each. Low brightness but fine for nightlight.


Dave

 

[Dave_H]

Here is another solar light approach. One of mine had corroded battery terminals from moisture,
a common failure with many of them, being not well (if at all) sealed, and outside including winter.
Casualties end up in a box, for parts. Normally the controller PCB, solar cells and LED are still OK.

I wired it to a 2D cell holder. Once D's are run down below 1v in a lantern, they are
transferred to this light. This runs dozens of hours as a nightlight, and allows cells to
run below the cutoff for single cell. There was no switch so one was wired up as well.

Some boost ICs may be limited to single-cell input so be a bit careful, don't use cells with
too high voltage. I like to open lights up, see how constructed, and which boost chip is used.
Their datasheets can be found online, except for COB chips with no markings so specs are
not known. There is small chance of damage using "nearly new" cells.

As for Joule Thief objective it may be "cheating" a bit but achieves a similar goal.

Similar "stacking" setups can be done with other cell sizes.

Dave

 

[thermal guy]

Are these available anywhere...even one?

He may make another run. I hope so I need a few more.

 

[unclearty]

Yeah...I'd love to grab one, too !

 

[vudoo]

Me too!