At what voltage are alkalines considered dead?

[Black Rose]

We have a call display unit next to our sofa that takes AAA batteries.
It was displaying the "replace battery" message again, so I replaced the batteries.

I checked the old ones with my analog battery tester and my DMM.

With the analog tester, they all read at the low end of "good".

With my DMM, under load the batteries show around 1.3 volts.
I checked the previous set of AAA batteries the unit expelled as well, and those are also showing 1.3 volts.

There is some voltage left, but it's probably not usable for long.

As stated in the title, at what voltage are alkaline batteries considered to be dead?

 

[MorePower]

It really depends on the voltage cutoff of the device in question. A typical remote control for a TV will stop working when individual cells are around 1.0V under the load of the remote. Some (poorly designed) digital cameras will cease to function when the loaded voltage of cells is 1.2V.

In general, an alkaline cell heads downhill pretty quickly when its loaded (depending on the load) voltage hits 0.9V.

What load did you use when checking the voltage with your DMM?

 

[Yoda4561]

Put a load on those cells, I bet they'll drop down to under 1 volt immediately.

 

[rockz4532]

i used to think if the resting voltage was below 1.4 volts it was dead

 

[Lynx_Arc]

those 3AAA caller ID boxes complain about low batteries easily and then run for over 6 months after they are *low* I gave up replacing them on mine tried nimh and a few months and it was complaining. I know have a 3AA caller ID box from GE that when it is low a tiny battery symbol flashes instead of the text blinking which is no fun. I was thinking about running 4 batteries in the 3AAA box instead with a resistor or something. Oh and alkalines are considered dead at about ~1.1v on most checkers I have taken them out of stuff and after resting for awhile that is about what dead ones rill rebound to.

 

[Black Rose]

What load did you use when checking the voltage with your DMM?

I don't know what the load is. All the documentation for the DMM says is that the battery test function uses a load test.

The DMM has 1.5V and 9V settings for the battery test function. I used the 1.5V setting for this.

I know have a 3AA caller ID box from GE that when it is low a tiny battery symbol flashes instead of the text blinking which is no fun.

This is a 3AAA caller ID box from GE.

 

[Lynx_Arc]

my 3AAA one is also from GE.... blue writing on front and flashes replace battery all the time now. I leave it right by my bed where I have to turn a light on to see it and it has been flashing for over 6 months and still works you just have to read between the warning.

 

[Mr Happy]

As stated in the title, at what voltage are alkaline batteries considered to be dead?

This is, unfortunately, all a matter of who is doing the considering. Electronic designers are supposed to consider them dead when the voltage gets below about 0.9 V or so, but many poor designers require the voltage to be higher than 1.3 V as you have discovered. Short of taking those bad designers out back and shooting them, there is not much you can do about the situation... :shrug:

 

[ltiu]

0

 

[Illum]

to me anyway...any alkaline that exhibit a voltage of 0.5V under load
believe it or not there are cheap cells out there that will measure 1.5V OCV out of the pkg but drops to almost nothing under the slightest load...and extra heay duty cells aren't the only exception

 

[NightTime]

0

Funny...

 

[Lynx_Arc]

to me anyway...any alkaline that exhibit a voltage of 0.5V under load
believe it or not there are cheap cells out there that will measure 1.5V OCV out of the pkg but drops to almost nothing under the slightest load...and extra heay duty cells aren't the only exception

I haven't seen any alkaline cells that drop like that near 1.3v and above but have had some that measures 1.0v that sag like mad under a slight load. I had some RCA manganese batteries (they were not alkalines) that measured 1.5v but my remote wouldn't work and finally I figured out on a load they were dead.
Typically if you don't have a battery drainer I would toss any alkalines that were less than 1.0v because only a few things can use the ~5% left in them.

 

[Illum]

I need to get another DMM soon...my last one sprout legs while I left the garage door open. I'm reading from an analog and the needle is near halfway below the 1 tick mark whenever I measure voltage through a load...something like a 2.2K resistor.

to me OCV means nothing...cr123As measure ~3V even when the ZTS says its dead, Silver Zinc will still say ~1.3V when they won't light an LED up two in series.

I've tested a couple batches of Duracell's [Mar 2008 all the way up to Mar 2015, AA, AAA, D] this way and yes, most don't go below 1V. at the moment I'm trying to figure out how to extract all the juice from them, using low current LED drivers and using them around the house instead of the AC LED nightlights.

With the current expenditure per year of batteries we as a household only yield about ~20AAs, even less on AAAs, and about half a dozen 9Vs from the smoke alarms and alarm clocks...which the Pak-lites doing a good job eating them. For the AAs I've rigged up a 5V boost circuit using the Max756 and ran CREEs on them, at 100ma CREEs are pretty bright actually. I dunno what to do with the AAAs, and about 30CR123As/year ...

 

[Lynx_Arc]

I must have 8 Dmms. I was given a craftsman autoranging dmm as a present and got 3 harbor freight cheapos on sale for $3 each and then my father passed away and he had done the same thing. I currently use the guts of a 3AAA headlamp that the case broke to light up my keyboard using weak batterie. I use rechargable AAs to help drain the weak ones when I don't have 3 of them. I have a AAA to AA adapter I made from a 2AA light that hade a 2AAA tube in it. I find I can get batteries under0.4v with a load and rested they measure about 0.7 to 0.8v or so. draining batteries this low will have about 1/5 of them leaking so I have a battery holder and don't put them in anything nice.

 

[Black Rose]

I have a few 3xAAA battery holders for powering those LED projects I have yet to start

I'll keep those cells around to use/drain with those projects.

 

[Lynx_Arc]

at one time I had a single 5mm LED wired to a variable resistor and hooked up to 6AA batteries that were all *dead*. I would dial it down till it read 4-5ma and leave it on as a nightlight and every so often I would check and dial it back up to 4-5ma when it got down too low. I have had batteries so low they reversed in the set, they were the *undead* batteries

 

[jerry i h]

...As stated in the title, at what voltage are alkaline batteries considered to be dead?

I guess it depends on what gizmo the batt is in :hahaha:
I have a Stanley Maxlife 369. I took some dead batts from the recycle bag, and stuck 'em into this thing. ALL of them light up the torch, and also lit up the red LED saying your batts are dead.

 

[Lynx_Arc]

I guess it depends on what gizmo the batt is in :hahaha:
I have a Stanley Maxlife 369. I took some dead batts from the recycle bag, and stuck 'em into this thing. ALL of them light up the torch, and also lit up the red LED saying your batts are dead.

that is the beauty of LED lights...... you can use 3 batteries direct driving that are dead out of incans and most non LED devices till they are dim then put the batteries in devices that have boost circuits and use them some more.

 

[etc]

When I used alks, I ran into the problem of them dropping to some voltage like 1.2V, too low to power what I wanted but not dead yet. In time I accumulated a colleciton of mostly-discharged cells.

I did find that CMG Infinity ran on these cells for a long while... but at a reduced lumens, which is pretty bad as it's low even on fresh cells.

 

[Stereodude]

As stated in the title, at what voltage are alkaline batteries considered to be dead?

When the device they're in no longer works.