I have an LED light up necklace, just a bunch of LED, no voltage regulator; that takes three AG13 batteries. The batteries it came with were labeled “AG13”, and lasted about 6 hours. I bought some generic LR44, which were supposed to be the same thing off eBay, which only lasted 3 hours.
Is there some difference, or did I just get some bad/defective/old batteries? They did have gummy stuff from the packaging on them and didn’t work at all until I scraped most of it off.
LR44, AG13, and A76 are all basically the same size battery. LR44 is the IEC designation where AG13 and A76 are manufacturer part numbers.
Just like AA batteries come in different chemistries (you can get cheap AA batteries that are carbon zinc and won’t last very long or you can get alkaline AA batteries that last a lot longer), the same thing is true for button batteries. LR44 is an alkaline battery. AG13, if it’s made by Energizer, is a silver oxide battery, which will last longer (as you found out). An AG13 made by someone else might be different though and might not last as long. However, the chemical abbreviation for silver is Ag, which is where the AG comes from in AG13 batteries, so most AG batteries will be silver oxide.
The IEC number for the silver oxide version is SR44. So either look for SR44 or look for silver oxide. Some folks use A76 for the alkaline and S76 for the silver oxide version.
PR44 is zinc-air in the same battery size and shape. It will last even longer than the silver oxide, but has a slightly lower battery voltage.
S-- cells are normally silver. L— cells are normally alkaline. Apparently, AG-- cells may be either.
BR and CR cells are lithium. M and N were mercury.
Batteries come with a ‘sell by’ date. I suspect that some traders might buy up batteries that are near or past expiry and then sell them on. If you still have the packaging - the date should be there.
The lower voltage may greatly reduce current. (voltage on resistor = Battery voltage - Diode forward bias* N … )… hence extending life.
Actually the amp hours of the batteries are all fairly similar, if used for low currents, but for high currents, the more expensive formulation lasts longer…
The drumming bunny is a high current application, so is the digital camera or incandescent torch…
LED’s are meant to be low current ? Sure the expensive batteries may last twice as long, but they cost 10 times the price !
The batteries that came out say
CNB
G13A
MICRO CELL
The Device says:
AG13
The batteries ones I bought say
LR44
BUTTON CELL.
The device uses three to drive 10 orange 3mm LEDs in the lanyard, and three to drive a brighter one in the attached charm.
The thing cost $8 at full mark-up amusement park prices. Even six alkaline cells cost more than that in retail packaging at Walmart. I’m assuming thought that even silver oxide would cost basically nothing if you buy a jillion of them from the factory in China. Wonder if the thing to do is just use it twice, toss it, and buy another one.
If these are silver oxide batteries, can I toss the used ones or do they need to go to the recyclers with my lithium batteries?
Batteries need to last 5 hours or I get eaten by zombies.
Buying these LR44 or cross equivalents at retail would insane. They are 10th the cost if purchased online via Amazon.
It might actually make the most sense to buy a 6 pack of similarly sized PR44 zinc air hearing aid batteries. They should work voltagewise, will be far cheaper (3-5 dollars for a 6 pack) , give long power output BUT zinc air does no last in storage like alkaline or silver oxide once the seals are pulled. Once the air seal tabs are pulled off the batteries and put into use those batteries they will output for days to weeks and then die.
See power capacity in grid at bottom - Will last 2-3 times longer than silver oxide.