1.

Clever Dude
April 30th, 2007 at 10:19 pm

Actually, our smoke and CO detector runs on 3 AA batteries. It’s made by Kidde. It has a nice lady saying “Fire Fire Fire. Warning Carbon Monoxide”. She sounds alot like the robot from Lost in Space.

2.

dong
May 1st, 2007 at 7:07 pm

My physics is rusty, but I recall voltage being additive. I think you should be able to hook 6 AA batteries in series to a standard fire detector….

3.

John Wilks
May 1st, 2007 at 10:31 pm

Simply hook up 8 AA batteries or 20 AAA batteries in a series to a standard fire detector. This invention should be able to run for at least 4 months straight! The biggest advantage to this is that every year you will have a ton of extra half dead AA or AAA batteries to mix and match to put into your wireless mouse, alarm clocks, diabetic monitor, etc.

4.

Gel
May 2nd, 2007 at 6:53 am

I work for a major manufacturer; reason why 9v is that so few other appliances use, so there is less chance of battery being borrowed for use in something else (less important!).
Rechargeables do indeed exist BUT are not suitable due to their dischrage pattern. Standard alklaine or zinc batteries will gradually deteriorate over 2 or 3 years; when voltage gets to low trigger warning level (around 7.5v) alarm then has to beep for 30 days once a minute(to tell you to change it); this so complies with product standard. Rechargeables when they go off, drop voltage like off edge of a cliff, so won’t give the all important 30 days protection.

5.

broknowrchlatr
May 2nd, 2007 at 7:45 am

Rusty is right, voltage is additive (when run in series). It actually does make sense that smoke detectors are run on 9 volts. AAs and AAAs are 1.5 volts. So you need 6 of them to make 9 volts. Is 6 of those really cheaper than 1 - 9 volt?

Here is how it works. There are 2 components in electricity. Voltage and Amperage. My analogy is comparing it to a river. Voltage is the speed of the river. Amperage is the width of the river. If you put 2 batteries in series (in a line), you double the voltage. If you put them in parallel, you double the Amperage (since it is like you are doubling the width of the river.) You can test this on your own. Get a small CPU fan. Hook it up to 1 AA battery and test the speed. Then put 2 AAs in a row and note that it will go faster. If you put two in parallel, it will probably not be faster than it is with 1 battery, but you will be able to run a larger fan.

If you have something that doesn’t take much to get going, but you want it to go really fast, you need high voltage, low amperage. If you have something really large that can go slow, you need high amperage. Look at children’s toys. A small child’s toy that jsut makes noise and has blinking lights will likely run on a couple AA batteries. A larger toy with moving parts will more likely run on 3-C batteries. They need more amperage ont he same voltage (C and D batteries run at the same voltage but higher amperage than AAs ans AAAs).

9 - volt batteries are purely for electical speed. Thus, the 2 most common uses are smoke detectors and controllers for RC cars. The former needs higher voltage for the high pitch squeel of the detector. The latter neads it to create the high frequency signal to the RC car.

6.

broknowrchlatr
May 2nd, 2007 at 8:35 am

One more thing. Since things that use 9 volt batteries usually require very low amperage, they last a long time. I buy the cheapest I can get. You can get a four pack at one of our local dollar stores

7.

EC
May 3rd, 2007 at 10:19 pm

They also make smoke detectors that use a 10-year lithium battery–and the battery is included! Last time we got a smoke detector I bought this kind. I figured it was worth a few dollars more initially, since we’d save on having to buy new 9-volts all the time.

8.

Midnight Raider
May 4th, 2007 at 1:46 pm

Seems to me someone needs to invent another common device or two that uses 9v batteries… thus we will have some place to use the leftover juice in our smoke detector batteries after we change them out.

Perhaps a 9v TV remote control….

9.

Nick
May 6th, 2007 at 4:50 pm

…or a battery-operated battery charger. Drain from the poor to give to the rich-argeable.

10.

J at Home Finance Freedom
June 1st, 2007 at 4:30 pm

There’s no reason to cry “conspiracy” just because my owner’s manual says to buy a 9-volt 2-pack every time someone says, “Hi, Bob,” put one battery in my alarm, and throw the other one away.

11.

deanking
June 8th, 2007 at 11:34 am

There is some national code that says a smoke detector must be able to run for a year on 1 battery. Therefore the instructions you saw to replace them twice a year does indeed point to a conspiracy. Either that or a CMA to keep from getting sued. Often they are the same thing. Also, that is why the OneLink is being recalled: it did not last a year on a set of AAs. Looks like someone should have fallen in line with the conspiracy.

12.

bec
June 22nd, 2007 at 2:36 pm

After phantom alarms that only went off in the middle of the night, I checked the First Alert web-site and found out that only Energizer 9 volt batteries should be used. We decided to change the batteries every 6 months but before we could, they went off again the other night. My sister in Oregon said there is a law there that 10 year batteries can only be used. 10 year??? We were never told there was such a thing so I went online and found them! Now we look forward to many nights of uninterrupted sleep…

13.

guit dude
July 20th, 2007 at 1:33 pm

The electric guitar industry is probably doing its share at keeping up the 9v battery demand. Guitar tuners, effect pedals, etc. All on 9v batteries. The guy who invented fire alarms was probably just in a heavy metal band and had tons of 9v batteries laying around…..

14.

Have A Life
August 6th, 2007 at 10:38 am

U need to get a life, man. Why fuss over pennies when you’re throwing hundreds of $ out the window on a car payment, instead of buying a good used car?

15.

me
October 21st, 2007 at 8:53 pm

I agree that the guitar industry might be involved. guitar that use active pickups use 9 volts too, and nothing else. except you need the best quality 9 volts for them to sound good.

16.

Evilempire
January 6th, 2008 at 2:38 pm

I cannot believe you said that the most trusted and accurate source of knowledge on the internet: FoxNews.com. They never report the facts, just made up propaganda to appease there political agenda and call every one who disagrees a liberal. Rupert Murdoch is the antichrist. Wikopedia him.

17.

eric
February 11th, 2008 at 3:34 pm

actually inside of a 9-v battery, are 6 1.5v batteries called AAAA batteries (quadruple A), they will fit in electronics that call for AAA batteries, but they are smaller in diameter than regular AAA, in fact, you can just peel the outer casing off of a 9-v battery, and you will see them, and can actually use them! as for the conspiracy, i do not think there is one, i think that the 9-v is there so that you do not have to replace as often, and also it sustains a voltage longer, in turn making it safer to use so that you do not have to change it out as often. and codes also require that a single smoke detector can run for at least a year on one battery, so 9-v batteries are a little more reliable than any other battery. this is the most logical reason.

18.

eric
February 11th, 2008 at 3:49 pm

by the way, when the manual calls to change the batteries every 6 months, that is only a safety precaution, because it has been determined that an average household has a smoke detector that goes off when you are cooking something, and those “false alarms” drain the battery a little, so in order to keep a good 12% factor of safety, they have to tell you to change your batteries every 6 months.

for the guitars, you need a low amp high volt (9-v) supply in order to obtain very precise readings, high amp readings will fluctuate the meters too much and in turn they will become inaccurate. But why not put in something in the circuit that lowers the amps? well then you would be going through AA batteries like crazy! you would have to replace them after like the fifth time you used them. that is why you use the 9-v,

think what you want about your conspiracy, but do not point fingers unless you know all the facts

19.

Mike O'Risal
February 18th, 2008 at 6:26 pm

Of course there’s a conspiracy! Otherwise, my wireless mouse and keyboard would both take the same size batteries. But they don’t. The mouse takes AA, the keyboard AAA. I bought them in the same box. Clear sign of conspiracy!

20.

eric
March 6th, 2008 at 12:23 am

do you even read what you write, you sound insane, your mouse has a different size battery than your keyboard because it requires more amps than your keyboard because your mouse has a tracking device (ball, or laser) that has to constantly be on when you use it, so therefore you need more amps to run your mouse, that is why you use AA in your mouse, and your keyboard uses AAA because it does not have any tracking devises, it just consists of buttons. just because AA and AAA batteries are the same Voltages does not mean that they output the same Amperage. and this might shoot your conspiracy down, but my logitech wireless mouse and keyboard both use AA batteries, so where does that fall in your conspiracy?

21.

electric freak
March 10th, 2008 at 4:41 pm

its tru there are aaaa batteries!!!!!!!!!!!!

22.

band_nerd
May 26th, 2008 at 2:24 am

Say, do you guys realize that almost every musician that plays an electric guitar or bass guitar and has any sort of effects pedal OR has active electronics on the instrument itself, are all using 9 Volts?

I would imagine that aside form a few toys and random electronics, that guitar pedals, remote controls and fire alarms are what keep the 9 volt around.

They do make rechargable 9 Volts. However, most chain stores like walgreens, CVS or Wal-mart are not gonna carry them since there isnt really a big application for them form a normal consumer stand point.

Me personally. I have active electronics in my bass and 2 pedals. Thats 3 9 volts. My guitarist has 2 pedals. My other guitarist has a pedal too. We change them before every live show, about once a month. Thats 6 9 volts a month between us.

I’m sure we aren’t the only band that does this. ;)

23.

chugg
May 26th, 2008 at 8:43 am

Psssst! Hey guys alkalines will take a couple of recharges with a little less life in em!Shhh

24.

Ray Jensen
August 2nd, 2008 at 2:49 pm

The music company I work for, power their electromagnetic products by super strong neodymium magnets. Result: high output and no need for preamps and such. Goodbye batteries

25.

Online film izle
August 11th, 2008 at 2:21 am

Psssst! Hey guys alkalines will take a couple of recharges with a little less life in em!Shhh

26.

Tercüme
September 17th, 2008 at 10:20 am

My physics is rusty, but I recall voltage being additive. I think you should be able to hook 6 AA batteries in series to a standard fire detector..

27.

Fingerling
September 30th, 2008 at 6:04 pm

Smoke detector batteries are changed twice a year - how expensive can that really be?