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Battery Stopper

An "off" button on batteries
  [vote for,

Batteries left in a walkman or flashlight will go dead after a few months, even if you never turn the device on. The only way to prevent this is to remove the batteries when not using the product. Which causes a big pain when there is a blackout and you have to try to find and insert the batteries in the dark.

Batteries with "off" buttons on them will let you turn off the charge while still leaving the batteries in the machine. Thus, the machine always has dedicated batteries inside it (no more surprises when you find an empty flashlight and no more batteries in your closet).

The "off" button can be as simple as an an electrical switch inside the battery, which blocks the current from reaching one of the terminals unless the switch is closed.

phundug, Sep 16 2003

Long life battery http://us.st.com/st...s/pdf/docs/6254.pdf
These last 10 years if you don't drain them [kbecker, Oct 04 2004, last modified Oct 21 2004]

Lightwave USA http://www.lightwave-usa.com/
Or, good grief, just join the 21st century and get a flashlight that'll shine for months on one set of normal batteries. [Ander, Oct 04 2004, last modified Oct 21 2004]


       I have never seen this in flash lights, except with cheap batteries that have internal leakage. Leakage gets worse with use. There is no switch to turn off internal leakage. Try to buy better batteries (link). Your walkman may have a bad low-battery detector that drains too much power to run itself.
kbecker, Sep 16 2003

       [dag] I wouldn't recommend turning the batteries around. In most cases it won't hurt, and in some cases it may actually prevent the batteries from discharging, but note the words some and most...   

       I could imagine a device with a diode to protect against reverse voltage, but it's a cheap diode that leaks a little. The next device in the circuit is the filter capacitor: an electrolytic capacitor that is designed only to be positively charged. At the very small leakage current through the diode, it won't explode, but I could certainly immagine that the capacitor could be damaged if left that way for a long time.   

       I'd suggest just taking a strip of electrical tape and folding it in half with the sticky side in, then inserting the strip between one of the batteries and the contact on the device. You may even be able to thread this out throught the crack around the edge of the battery compartment so you can grab the end of the strip and jerk it out to activate.
scad mientist, Sep 16 2003

       My emergency flashlight is in the freezer.
Shz, Sep 16 2003


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