Is Peukert's Law Applicable for Calculating Battery Life at Microampere Levels?

[frenchero]

Hi everybody,

I would like to use a 9V pp3 battery with a device with a rate of order of µA. Iwanted to use Peukert's law to calculate the duration of my battery but I am not quite sure if it is applicable for such low current... Won't a battery with 1200mAh capacity discharge too fast?

Thanks

Damien

 

[berkeman]

Hi everybody,

I would like to use a 9V pp3 battery with a device with a rate of order of µA. Iwanted to use Peukert's law to calculate the duration of my battery but I am not quite sure if it is applicable for such low current... Won't a battery with 1200mAh capacity discharge too fast?

Thanks

Damien

Peukert's law appears to apply to lead-acid batteries, like car batteries, not to 9V alkaline batteries.

To calculate battery life, look at the battery datasheet (get it from the manufacturer's website), and look for the discharge time line for that low current.

 

[Mech_Engineer]

You will have to look at the battery's self-drain rate and shelf-life, because just taking into account the load by itself won't give you an accurate estimate. For example, 10 micro-amps at 9V (90 micro-watts) would take 5000 days (13.7 years) to drain a 1200 mAh 9V battery.

 

[Mech_Engineer]

Peukert's law appears to apply to lead-acid batteries, like car batteries, not to 9V alkaline batteries.

It also appears that Peukert's law is meant to be applied to when the drain rate on a battery is larger than 1A, but not necessarily the micro amp range.