When are AA and AAA batteries concidered Dead

[Advan]

NIMH all the way. I switched after alkaline batteries leaked and ruined my 2nd D-cell maglite. Now I use 'em for everything, except the transmitter for my wireless thermometer and my trail cam, as they just don't seem to last in the cold weather.

 

[WWheeler]

NIMH all the way. I switched after alkaline batteries leaked and ruined my 2nd D-cell maglite. Now I use 'em for everything, except the transmitter for my wireless thermometer and my trail cam, as they just don't seem to last in the cold weather.

Eneloops outlast alkaline in cold weather by a long shot. It's if/when it's hot they drain more quickly.

http://main.panasonic-eneloop.eu/en/faq

Does temperature have an effect on their performance?
Yes, temperature does have an effect on eneloop's performance. If it is too hot, the high temperature could cause the battery to discharge at a more rapid rate. On the other hand, eneloop works better than alkaline, and other rechargeable batteries in freezing temperatures!

https://www.panasonic.com/global/consumer/battery/eneloop/technologies.html

 

[Coolabah]

Eneloops outlast alkaline in cold weather by a long shot. It's if/when it's hot they drain more quickly.

http://main.panasonic-eneloop.eu/en/faq



https://www.panasonic.com/global/consumer/battery/eneloop/technologies.html

I just love this sort of debate ( just so there is no confusion-totally no sarcasm etc - this is just me talking )

Where else apart from GJ would you find such a great, passionate and informative discussion on anything and everything including batteries ! .... now back to our program...

 

[katiexoxo]

Those graphs are bs. Even if they were legit, they would take the crappiest alkaline battery ever and test it against a beefed up eneloop. It's not just panasonic, but every brand that makes comparisons like that are waaay off

 

[barrybeefburger]

tagged

 

[WWheeler]

Those graphs are bs. Even if they were legit, they would take the crappiest alkaline battery ever and test it against a beefed up eneloop. It's not just panasonic, but every brand that makes comparisons like that are waaay off

You can say that based on ?, but I can also say that I've actually been using them for some time and all of those 'bs' graphs agree quite well with my experiences with them. Earlier in this thread I linked a pdf of tests done independently and they came to pretty similar findings as Panasonic did. They didn't do the cold test though.

It's just a fact. Eneloops have consistently noticeably outperformed alkalines in every device I've used them in, and then I don't have to throw them away when they are dead.

 

[American Locomotive]

Those graphs are bs. Even if they were legit, they would take the crappiest alkaline battery ever and test it against a beefed up eneloop. It's not just panasonic, but every brand that makes comparisons like that are waaay off

No it's not, notice it says "High Power"? Alkaline batteries are absolutely horrible at high discharge rates. You loose a ton of their capacity just from internal resistance of the cell. This is why things like big digital cameras with bright-flashes plow through disposable alkaline.

Duracell alkalines would get be maybe ~100 shots out of my old Canon camera. NiMH rechargables would get me around 400, and the Energizer disposable lithium would net me well over 500.

At a 0.5 amp discharge, most alkaline batteries will only give you around 60% of their rated capacity. At 2 amps, that drops to ~30% or less of their rated capacity.

http://www.powerstream.com/AA-tests.htm

 

[ddawg16]

No it's not, notice it says "High Power"? Alkaline batteries are absolutely horrible at high discharge rates. You loose a ton of their capacity just from internal resistance of the cell. This is why things like big digital cameras with bright-flashes plow through disposable alkaline.

Duracell alkalines would get be maybe ~100 shots out of my old Canon camera. NiMH rechargables would get me around 400, and the Energizer disposable lithium would net me well over 500.

At a 0.5 amp discharge, most alkaline batteries will only give you around 60% of their rated capacity. At 2 amps, that drops to ~30% or less of their rated capacity.

http://www.powerstream.com/AA-tests.htm

See....^^That's^^ how you do it....
Back up your statement with a link

What some may not notice unless pointed out is the discharge slope on voltage. Notice how the voltage for the Alkaline drops vs the NiMH?

NiMH (and NiCad) have a much flatter voltage during discharge.

Downside....you can't really use voltage as and indicator of health like you can with the Alkaline.

 

[Advan]

Eneloops outlast alkaline in cold weather by a long shot. It's if/when it's hot they drain more quickly.

http://main.panasonic-eneloop.eu/en/faq



https://www.panasonic.com/global/consumer/battery/eneloop/technologies.html

I agree with this information. However, neither a wireless thermometer transmitter nor a trail cam should be continuously drawing 500mA.... As well, I'm talking more like -20° C, which I'm sure must mean something. I've seen it time and time again, good alkalines outlasting good NiMH's in these particular situations.

 

[American Locomotive]

I agree with this information. However, neither a wireless thermometer transmitter nor a trail cam should be continuously drawing 500mA....

...and neither do most devices. It's those short periods of high current draw where alkaline batteries do poorly. Take a ~2.2 Ah rated alkaline. At a 2 amp load, it has an effective capacity of about ~0.7 Ah, possibly lower. If you draw that 2 amps for just 1 minute, you've just exhausted 4.8% of the battery in just one minute. Where as if it could maintain its capacity at high load, you would have used only 1.5% of its capacity.

As well, I'm talking more like -20° C, which I'm sure must mean something. I've seen it time and time again, good alkalines outlasting good NiMH's in these particular situations.

It's funny you mention that, because even according to Energizer themselves, NiMh batteries have better cold-temperature performance down to around -5° C.

Where NiMH batteries are not appropriate is long-term, slow down devices (like a wireless thermometer), because their self-discharge will actually be higher than the energy the device is using.