Key Chain Laser Batteries

Try again after a Firefox crash ... well, I bought two pkg's of 1.4VDC "Hearing Aid" batteries for my cheap (gold colour) China Key Chain red lasers-- these batteries fade with just a few sec of continuous use. What you need to buy for "button batteries" for laser applications is the 1.55VDC Alkline Batteries labeled for "toys" applications. They are very pricey at hard retail ie DuraCell. I found them at the dollar store 2 for $1 and they work great. So you save money. My lasers take 3 button batteries each.

Dollar Store Alkaline Labeled for: AG13 357A CX44 LR44W

I gave the "hearing aid batteries" (#675) to a friend whose parents have hearing aids, I could have returned them to Wallgreens though. Now they can hear the news. /ubbthreads/images/graemlins/smile.gif

Always use alkaline AG13/LR44 cells in a keychain laser pointer; those hearing aid batteries are designed specifically for very low current applications (less than 10mA or 15mA); go much above that and their terminal voltage will drop rather rapidly as you have already found out. Most keychain laser pointers will use 25mA to 45mA of current; more than zinc-air hearing aid batteries can provide over the long term.

Yeah, I wish I had known-- I already returned one set of "store brand" made in U.K. also their Energizers are made in U.K., to the Wallgreens Store manager for a replacement. I thought they were just defective.

Cheap AG-13 /ubbthreads/images/graemlins/wink.gif

Often, it's just cheaper to buy a bunch of $.99 cent pointers or other toys with the batteries in them, when you see them at the dollar store, or on closeout.

It's kind of amazing when you think about it. $.99 pointers...

Imagine if you went and showed the engineers and scientists working on the very first ruby rod lasers in 1960 a cheap pointer. Granted, they were cutting through razor blades with their flashcoil pumped ruby rods, and were half-jokingly measuring the strength in "Gillettes", i.e. the number of stacked razors they could cut through. But continuous solid-state lasing from a few tiny watch batteries would have been absolutely amazing to them, IMO.

Could you further imagine the look on their faces when you showed them that the actual "laser" was the tiny diode in the tip, and that the rest was just a body for optics and batteries. Then the look would be even more priceless when you told them that they only cost $.16 in 1960 dollars, and that they came in by container ship from Red China?

The shade of purple their faces turned would be what, 400nM or so? /ubbthreads/images/graemlins/grin.gif