How long do Batteries last?

Hi, how long typically do energizer ultimate lithium batteries last? i have tried now 2 sets of them, and they are lasting between 2-3 weeks, i thought weatherflow said they last around a year? average low temperature was around -11 celsius or so, so not that cold, thanks


I think its the extra debug info that is being sent that is meaning they are not lasting very long
having said that
its summer here and no problem so far with battery life
(battery in my air must be like 6 months now?)

Hello Gary
if you have a test device, yes battery life is short as the unit sends out way more info then a regular one

If you device is a basic normal unit it should last at least a year

Some Air units seem to have some problem, known to WF

If this is the case contact them directly via this system. They’ll help you quickly

For me its been now a 4 months and the voltage is 3.52, so I think it can last for three years if the voltage stay decreasing at this rate, also I think the weatherflow means it can last one year in the harsh environments.

thanks for the quick replies, its not a test device, just normal, i have contacted support

Are the batteries for the Sky or the Air?

its the air, I will be getting a replacement

Good deal. I put regular cells in my Air and it’s still reading 2.94 vdc. So your Air definitely has a power issue.

My AIR has had the same set of Ultimate Lithium batteries for exactly 5 months now. Started at 3.59v dropped to 3.05v in January when we were down to around -25 F but they have rebounded up to 3.46v as of today. I would say a year of battery life looks like a reasonable estimate.


FWIW, my Air has been running for 260+ days straight at last count on the original bulk lithium batteries. It is near freezing as I type this, and the battery card is reading 3.43v.

As others have said, contact WF support if you have replaced lithium batteries in an Air because it is not normal…

Hi, got my replacement, and everything seems to be fine. I had a unit that weatherflow calls “hot air” a known problem for some where the battery draws more power discharging faster and heating up the sensor 2-3 celsius. Its funny, I originally emailed them back in December stating my unit seemed to be 2-3 celsius higher then anyone else. (I didn’t know about the batteries problems yet, I thought I just had a defective battery).


I’m a little concerned about the batteries in my SKY (1565). The voltage has really dropped over the last few days and I’m just wondering if that is normal. The status still says Good - so that’s good, right?

Maybe I worry too much about my WeatherFlow?

How low has it got? This should give some info of how low it can go and still operate correctly:

For AIR, at approx 2.4V the lightning detector will disable (because it requires more power) while the other functions will continue to report until the level drops under ~2.0V. SKY will operate down to about 2.0V. Incidentally, the power curves for lithium batteries tend to perform above ~2.7V for a remarkably long time, then when they start to fade, the drop off is quite sudden.


Well on June 9 it was between 3.3 and 3.4, since then it has taken a dive and is now 2.9. But thanks for letting me know I still have a ways to go before it stops. New batteries are on their way.

2.9 volts in just a few weeks? Did you use Energizer Ultimate Lithiums as recommended???


Yes I used Energizer Ultimate Lithium.

Put in a support ticket. There is an issue.

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Today the status is Replace. I hope it is just the batteries and not my Sky. Voltage is down to 2.07Sky%20Battery%20Depletion

Most of us have Sky’s running for months with the same set of batteries. Mine is running near 90 days and still at 3.14V and it is set to measure wind every 3 secs (not in save mode)

As said Gary, open a ticket with support. They’ll look closer but most probably the Sky has an issue.

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I did open a ticket with support. Thanks for the nudge to do that.