When is a AA battery considered dead?

[Short.Circuit]

THis is kind electrically related, I take lots of photo-s of residential rough-ins...
My digital camera seems to go through batteries @ a pretty good clip. I'm curious if there is anything else I can do with the AA batteries after they are no good for the camera? I think they measure under 1.3V DC or so...
thanks

 

[TOOL_5150]

I would go with rechargables. Thats all I use in my camera, they work well and recharge many times.

~Matt

 

[iwire]

Stop using the flash if you can, also do not use the LCD view screen if it has one.

 

[gadfly56]

THis is kind electrically related, I take lots of photo-s of residential rough-ins...
My digital camera seems to go through batteries @ a pretty good clip. I'm curious if there is anything else I can do with the AA batteries after they are no good for the camera? I think they measure under 1.3V DC or so...
thanks

I have a Mini-MagLite with the LED bulb. Usually there's enough juice left in a "dead" AA used for high-draw applications like cameras to keep that Mini-MagLite going for a while.

 

[fishin' electrician]

Along with what the others have said:

I believe some cameras will put a small drain on the batteries even when not in use. I started opening the battery door of mine when I'm not using it and it seemed to help them last longer.

 

[winnie]

A battery is dead when the chemicals that get used for generating electricity are all used up.

The problem is that most all loads require a certain minimum voltage to operate, and as the chemicals get used up the battery voltage will drop. Then the battery has internal impedance, which means that the output voltage will get lower as the load current increases. On top of this, the internal impedance changes as the chemicals get used up, generally the battery impedance goes up as the battery gets used up.

Loads like digital cameras are 'high drain' loads, simply meaning that they call for lots of current at least some of the time. If the internal resistance of the battery causes the voltage to drop below the minimum needed, then the camera claims that the battery is all used up. Since most of this drop will be caused by internal impedance, measurements of the 'open circuit' battery voltage will tell you little about the state of charge of the battery.

For 'high drain' applications that take AA batteries, I highly recommend 'low self discharge' NiMH batteries, and have good experience with the Sanyo Eneloop brand. NiMH batteries have a lower open circuit voltage than alkaline batteries, but they also have a much lower internal impedance, so the net voltage under load is actually higher. The low self discharge is important because you might have your batteries sit for a month or two before you need them, and regular NiMH batteries (with nominally higher capacity) will have discharged without any useful output.

-Jon

 

[zbang]

I used to take the batteries out of my maglite and use them in the pager. They'd last about a week, then they were stone dead. Part of the monday morning ritual was swapping the pager battery.

 

[sameguy]

Alive ? charged maybe then run down... I use NMH or what ever it is last long. Look for a Lacross charger at Amozon with batt. cheap and good.

 

[gar]

100226-1959 EST

Short.Circuit:

I have a Minolta. When off this camera seems to have a substantial load on the batteries.

My use of the camera is limited and I found the use of rechargeables not satisfactory because of this off state discharge from the camera, and their own self discharge rate. Clearly badly designed electronics in the camera. It is a major nuisance to keep removing the batteries from the camera. Rechargeables tend to have a self discharge rate with no load that is much faster than a carbon zinc battery.

When the unloaded voltage of the Energizer cells that I use drop to about 1.44 V my camera fails. These work fine in my pager and still last a long time in the pager. But the pager requirement for batteries is small and it works to a much lower voltage.

Currently the batteries in my LED MagLite read 1.4 V unloaded. I do not know the failure point for the Maglite. It may be in the range of 1.2 V. However, when failure occurs it is abrupt. I get a momentary flash when turned on.

.

 

[ohmhead]

THis is kind electrically related, I take lots of photo-s of residential rough-ins...
My digital camera seems to go through batteries @ a pretty good clip. I'm curious if there is anything else I can do with the AA batteries after they are no good for the camera? I think they measure under 1.3V DC or so...
thanks

Well my boss gets a bigg pack we kinda do what you do lots of shots in one day but if he runs out i take his batterys out of his camera and use them because he never comes out in the field so there always good .


I was told that nimh batts are better than lithium once they start past a certain discharge there going to die and must be charged everyday so watch which one you get its not the electronics its the batt used in it .

 

[flashlight]

Have had very good luck with rechargeables in my headlamps and maglights, The ones I use are fully charged at 1.4V, which could be a problem in some applications as noted by another poster. Non rechargables when at 1.3V or less I use for clocks or put in the bucket I'm saving for either recycling or when I buy the charger I saw in the airplane catalog that is supposed to charge all batteries, whether designated "rechargeable" or not. Has anyone seen/used this ?

 

[tom baker]

I use a Ray O Vac 15 min rechargeable battery. The rechargeable batteries all loose a little bit of a charge every day. With the 15 min batts I pop them in the charger and they are quickly charged. Also rechargeable batteries have a lower cell voltage, 1.3 compared to an alkaline battery at 1.5 V

 

[Besoeker]

when I buy the charger I saw in the airplane catalog that is supposed to charge all batteries, whether designated "rechargeable" or not. Has anyone seen/used this ?

I used to try recharging non-rechargeable batteries. It did give them a bit of extra life but they had a tendency to leak and cause corrosion.
It was a long time ago. Maybe they are better now.

 

[kbsparky]

Along with what the others have said:

I believe some cameras will put a small drain on the batteries even when not in use. I started opening the battery door of mine when I'm not using it and it seemed to help them last longer.

Does that make your camera "forget" the proper date/time?

 

[fishin' electrician]

Does that make your camera "forget" the proper date/time?

It didn't until you brought it up.

Never noticed it before, I use it sparingly enough that it's not a problem, but will have to keep it in mind when taking pictures for important documentation.

 

[gar]

100227-1018 EST

With the batteries removed for 12 hours my Minolta did not loose time and date, and over many years the time has drifted only 7 seconds. I will leave the batteries out for a longer time.

On a related subject, but different product. In the early 1980s IBM added a battery backed up real time clock to the XT PC. Note, the original PC came out about October of 1981. The XT improvement was a year or so later. The original PC required manual setting of the clock every time the machine was booted. When IBM added the real time clock it was, I believe, designed and made by Motorola. The battery for backup was moderately large, maybe 0.5" x 1" x 1.5", and only lasted about 3 months.

Somewhat before 1975 CMOS static memory chips became available that could retain memory with current levels on the order of a microampere. By about 1980 Dallas Semiconductor was doing a lot of different things with this capability. This involved a real time clock in a small package including a battery that could operate and maintain time for 10 years with no external power. Battery life was extended by applying external power. This was not a rechargeable battery. The Dallas products should have been well known by IBM designers.

The indirect information that I heard was that IBM considered Dallas to be too small and therefore did not use the Dallas product. The result was a large unnecessary cost and trouble for the IBM PC customer. That in my opinion was a bad engineering or management decision.

.

 

[K8MHZ]

Years of experience with camera batteries

Years of experience with camera batteries

A battery is considered dead when it is depleted to a defined portion of it's capacity. Generally, if we see a voltage of 80 percent or less, the battery is 'dead'. Your device has a set voltage value that it considers dead and will shut down the device at that point. Some IC's don't like low voltage so electronic devices now shut down rather than continue with low voltages.

What type of battery you should be using depends on the way you use your camera.

If the camera will be sitting for longer than a day or two between shots, non-rechargeable lithiums are the best choice. Not only do they out last alkalines by a factor of 5 to 7, they have a shelf life measured in years and most important have practically no self discharge. I can stick lithiums in a camera and stash it somewhere for five years and it will still have the same charge in the battery as when I left it.

Lithium batteries are used in the camera I carry with me on a daily basis. Since the camera may be in my pocket for a couple weeks without being used, re-chargeable batteries are out of the question. They discharge themselves in a relatively short period of time.

If the camera is used daily, especially for many shots per day, NiMH batteries are the best choice. Get a 1 hour charger. With two changes of batteries, one on the charger and one in the camera, you will always have power.

I only use alkalines if the above is not available. They work but don't last very long. About 1/3 as long as modern NiMH AAs which are now in the 2500 mAh range.

Heavy duty batteries are just a waste of money in a camera.

Also be advised that many cameras also have a small button cell inside to keep the time and date set while changing batteries. Although they do last for years, it is wise to change them before they fail. They can be removed and tested, but for two bucks why not just change them every couple years?

 

[gar]

100228-2254 EST

After 30 hours without batteries in my Minolta the time and date was still valid. There is no obvious backup battery for the real time clock. They may use a super-capacitor for this purpose.

.

 

[K8MHZ]

100228-2254 EST

After 30 hours without batteries in my Minolta the time and date was still valid. There is no obvious backup battery for the real time clock. They may use a super-capacitor for this purpose.

.

My small Canons use a button cell battery along with AA's. One purpose of the button cell is so the lens still can retract when the AA's fail.

Some cameras may use capacitors, but some of the low end (cheap) use button cells that are permanent. Once the small battery is dead, any memory function will be lost although the camera will still take pictures.