AAA Eneloop vs. "normal" battery

[gloob]

Hello,

I have some battery based sensors and noticed that they last for about half a year on normal not rechargeable battery but only 2-3 months on eneloops.

What are your experiences? What kind of battery do you use for battery based sensors.

Regards
Stefan

[qqlapraline]

I have that kind of experience, and, according to my searches, rechargeable batteries are a much less favorable self-discharge curve than regulat batteries. It means that, even at very low current, rechargeable batteries will discharge way faster than alkaline ones.

Here is a source:

http://batteryuniversity.com/learn/article/elevating_self_discharge

The best overall are lithium based (not rechargeable) batteries. Like these ones:

http://www.energizer.com/batteries/energizer-ultimate-lithium-batteries

Qq.

[mfalkvidd]

Alkaline batteries outperform NiMh when the average current draw is ~100mA and less. With half a year battery life the average current is 1000mAh / (6 * 30 * 24) h = 0.23mA which is much less than 100mA.

See http://www.paulallenengineering.com/blog/alkaline-vs-nimh-under-different-loads and http://www.paulallenengineering.com/blog/kirkland-signature-alkaline-batteries

[Nca78]

Hello, I use CR2032 which are more constraining. I think normal alkaline batteries are the best choice if you don't mind the volume.
You should get much more than 6 months of battery life with alkaline batteries, what is your setup ?

[cimba007]

Currently I mostly use Alkaline but on some project I use old handy-lipo-batteries. They are nice since they include some basic safety circuits.

Most of my projects work on 2xAA-Alkaline with 1mhz-AVR .. pretty good experience so far .. even with uses ones.