is this at 1.55Volt LR41 battery and the current can come to microAmpe?

6 hours ago, Trần Thành 23456 said:

is this at 1.55Volt LR41 battery and the current can come to microAmpe?

Assuming that a LR41 battery lasts for 5 years in a digital wrist watch and initially contains 30 mAh then a quick calculation gives the average current 0,46 micro amperes.

1 hour ago, Ghideon said:

Assuming that a LR41 battery lasts for 5 years in a digital wrist watch and initially contains 30 mAh then a quick calculation gives the average current 0,46 micro amperes.

I don't think it works quite as simply as that. Batteries will degrade over five years, even if you are not drawing a current. So some of the 30 mah will have been used, but a substantial amount will have just seeped away due to aging. 

3 hours ago, mistermack said:

I don't think it works quite as simply as that.

I agree, a detailed analysis requires more assumptions and/or information from OP. Let’s try to rephrase the answer: under the stated assumptions, constant power usage, and ideal and lossless conditions the current will be below 1 micro ampere.

 

58 minutes ago, Ghideon said:

I agree, a detailed analysis requires more assumptions and/or information from OP. Let’s try to rephrase the answer: under the stated assumptions, constant power usage, and ideal and lossless conditions the current will be below 1 micro ampere.

 

There's always some parasitic discharge somewhere in a cell, isn't there?

1 hour ago, StringJunky said:

There's always some parasitic discharge somewhere in a cell, isn't there?

As far as I know that is generally true, I'm unaware of any battery chemistry that allows for unlimited storage. Self-discharge depends on storage environment, chemistry, brand, temperature (and probably others I have missed). I intentionally neglected all this in my ball-park calculation. Another thing I neglected is that a wrist watch may have functions that temporary draws additional power; backlight, alarm etc. Maybe OP returns with follow-up questions or additional information to take into account...

You could also look at it from another view point, and work out how much energy was used in making the battery, and that gives a more real total of energy used.