The Ultralife Lithium 9V Smoke alarm challenge

VidPro

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First the story:
there is 9 smoke alarms in this house, and about every 6 months one of them will start beeping low battery, this is the most obnoxious things in the world. you can hear this low battery signal in your Brain, but determining which unit it is from is hard because of the short high-frequency peircing sound. a few days after replacing that battery, another one will start its incessent beeping, waking people up and all.
its like the house from hell :) as you can be sure that you will be woken up by some obnoxious beeping from something , be it the UPS (power supply), the phone, or the smoke alarms.
SO
replacing all the batteries, even if they have a few more months of life (or not) has to be done about 2 time a year. no big deal right? well it isnt always 6 months, and sometimes one will have beeped all night, and when it warms up, it will stop beeping , but only when your Looking for the dang thing.

The Test Subjects:
these are AC&DC smoke alarms, that are "Ganged" meaning chained together via wiring in the house, a 3rd wire is a trigger wire that triggers EVERY smoke alarm in the place when only one goes off (from smoke), another nightmare trying to figure out WHICH one of them is going off.
they aparentally are testing the battery to death, as i suppose would be fine, beings the smoke alarms are important safety items.

we were using fresh alkalines in them of brand names, like energyser, ray-o-vac max, and duracell.

the Change:
better make that the Dollers :) i spent neer $70 on Ultralife Lithium 9V cells, to See if i could get a temporary reprieve from this constant. i made sure it was from a reliable source, and not a knock off.
the lithium cells have the features of long shelf life, a tiny bit more capacity, and could have had a slightly better voltage holding.

Some Results:
The replacement to Ultralife lithium was done in 1/11/07 (december last year) and the first one went belly up, in only 5.5 months, the second in only 7.5months.

Some starting conclusions:
IF your smoke alarms suck up batteries for lunch
IF your smoke alarms use batteries up in less than a year of time
Then, putting in a $7 battery in is a waste, i would have been better off replacing Every one every 6months, than to waste this kind of money trying to extend the time.

its not over yet, but this is the SAME loop i was put into with alkaline, and now it woke me up beeping again twice, %&*!#, so i am not impressed.

Disclaimer, your results would definatly vary, if your smoke alarms last longer between battery changes. this post is the opinion of the poster, who mearly cataloged the times for his own purposes, use the above information at your own risk.
 
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Re: The Ultralast Lithium 9V Smoke alarm challenge

Hello VidPro,

I use this
4h3v2g.jpg

reason because I could source them cheaper. I would use any name brand 9V Lithium as long as I can find them. I think they are $5 each.

Do you know what's the use before date on your Ultralast?
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

Hello VidPro,

Do you know what's the use before date on your Ultralast?

i dont remember, the packages are in the trash. There is just some code on the side of the battery itself. It was WAY long though, like sometime in 2012 or 2015 or something, long before they would be dead from the way these smoke alarms work.
 
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Re: The Ultralast Lithium 9V Smoke alarm challenge

I am thinking if 3x CR123 wired serial to make 9V that would be lots of capacity. But I wonder if they well for low discharge application. Since they are $1 each, a 9V will be roughly ~$3.

There's another type of Lithium 3.6v battery made by Saft for memory retention. They also make batteries for space satellites. So they should be pretty reliable. Wire three makes 10.8v, that's pretty close to a fresh 9v alkaline. I have one of the Saft Lithium battery in my 15yr old multimeter, it's still going strong.
 
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Re: The Ultralast Lithium 9V Smoke alarm challenge

i am thinking if its already hooked to the AC anyways, why the suckers cant just put a LSD ni-mhy pack in it and be done with this madness :)

i just wish they would test the battery a bit less often or something, i have seen DC only smoke alarms last longer on a battery than these hooked to the wiring. its just one of my pet peeves.
 
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Re: The Ultralast Lithium 9V Smoke alarm challenge

The short battery life surprises me. Maybe you should use something simpler.

I am, or have been in the past, familiar with eight or ten of the simple smoke detectors that use 9 volt alkalines. I'm pretty sure the batteries last at least 3 years. I'm guessing they last longer than that.

By the way, I have a kick-*** Nighthawk carbon monoxide detector. It uses 3 AAA cells and has an LCD display with a 3 segment battery monitor. I wish they made smoke detectors like this. I would be reluctant to use anything but the recommended alkalines in this CO detector, but don't you know, one of the alkalines I had in there originally leaked. I'm now using eneloops.
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

That's really strange if they are hooked into AC as well. all mine has several years old 9v batteries in them but they still tested new when I checked them with multimeter. Maybe the installer was lazy and let them run on DC only?
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

That's really strange if they are hooked into AC as well. all mine has several years old 9v batteries in them but they still tested new when I checked them with multimeter. Maybe the installer was lazy and let them run on DC only?

good point, knowing some constructions, they could be hooked up basAckwards, after all some of the power plugs were, a small $11 power analiser spotted them, and a few minutes later i re-polarised some plugs.

They have 2 lights, a green one and a red one, when the AC isnt hooked to it, or it isnt ganged? one of the lights does not go on. and i sometimes get a few minor sparks when connecting, that indicates there is power in existance. so as far as i can tell they are connected, but i would also bet they are the cheapest to "code" ganged modules available.

one of the modules has been replaced, zero selection was avilable for ganged ones that fit the connector, and luckily it has the new on the face battery door, so i dont have to take it OUT to replace the battery, that Newer one might use less battery, i wont know till it too starts beeping.
 
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Re: The Ultralast Lithium 9V Smoke alarm challenge

Building code around here now requires smoke detectors be connected to AC and have an internal battery backup (presumably 9V). I've only lived in my new construction house for ~7 months, so I have no idea how long the batteries will last in these.
 
Re: The Ultralast Lithium 9V Smoke alarm challenge


Because I already had some extras, these are exactly what I have in my smoke alarms (battery powered only models.) They work fine in mine, but read on...

Based on previous discussions on CPF about smoke alarms, IMHO lithiums of any kind in smoke alarms could be a safety issue. The discharge curve is very steep at the end, and this could cause either of two problems:
1) The low battery warning could be so short that no one ever hears it, or...
2) The discharge curve is so flat that it's possible that there could be inadequate warning in the event of a real alarm.
(This is why I stopped using the Ultralast 9v in smoke alarms, because it was just too tempting to leave them in until the they were too far gone.)

Because of this, I charge these iPower LiPo 9v batteries monthly, and would stick to alkalines were i not prepared to do this. If I burn my toast and set off the alarm, the battery in any alarm that sounds goes immediately on the charger. The smoke alarms use so little power that these batteries have probably 80-90% of their capacity left at the end of the month, but this way I can sleep easy knowing they have plenty of juice to sound an alarm at all times.

BTW, these iPower LiPo 9v batteries do work great in transistor radios, hand mics and everything else I've tried them in, so far. Mine are about a year old, so I have no idea how well or badly they'll age, but I've been very pleased with them, so far.

Hope I'm not sounding too preachy, here. Be safe.
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

Maybe the installer was lazy and let them run on DC only?
My detectors run on 9V DC only and the batteries last more then 2 years.

What a pain in the neck if you have to replace batteries every 6 month. One option to avoid the search, would be to replace all batteries on a regular schedule.
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

Smoke alarms cry wolf so often that I don't even believe them any more, which is pretty bad, since if there were an actual fire and the smoke alarm happened to do what it was supposed to, I'd just silence it. I've pretty much given up on even the most expensive models, as they have the same false alarms and un-shut-up-ability problems as all the rest.
Fortunately, I made substantial better experience with my smoke detectors. Very reliable, only had two alarms and both because of smoke from the kitchen. Not a single false alarm in 10 years - they are so silent that I test them from time to time with a smoking candle (some fun might be involved there :whistle:). They have a switch to silence the alarm and can be hooked together. Run on 9V batteries for more then 2 years - even with the cheap ones (think Ikea).

So, they are out there - unfortunately for you, I got them from Switzerland and they are quite expensive (approx. $60 a pop). But well worth the money, if you ask me.
I can try to find a link, if anybody is interested.
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

I believe your smoke detectors are of very low quality or are actually defective. Get new better quality smoke detectors.
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

Did you test the voltage of the batteries before and after? I'd be curious what the voltage reads. I really think you smoke alarms are faulty. BAD, replace these instead of your batteries.
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

Stop changing your batteries and change your smoke detectors! I have dual sensor smoke detectors and I have never changed a battery in under a year..... and change them about every 18 months whether I need to or not. Lithium batteries do not have that much higher capacity versus alkaline at low discharge rates so there is absolutely no advantage in that. I also have a First Alert smoke detector that has a 10 year battery life Lithium pack.... I am about 5 years in an it is still working. After 10 years, you need to replace the whole unit.


Semiman
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

Stop changing your batteries and change your smoke detectors! I have dual sensor smoke detectors and I have never changed a battery in under a year..... and change them about every 18 months whether I need to or not. Lithium batteries do not have that much higher capacity versus alkaline at low discharge rates so there is absolutely no advantage in that. I also have a First Alert smoke detector that has a 10 year battery life Lithium pack.... I am about 5 years in an it is still working. After 10 years, you need to replace the whole unit.

Semiman

Actually, lithium 9V batteries have nearly double the capacity of alkaline 9V batteries.
 
Re: The Ultralast Lithium 9V Smoke alarm challenge

I have exactly the same problem, using these :



Just in one of my six smoke alarms (It's a large house), just started beeping, 9 months after fitting.

Alkaline 9v's lasted around 18 months.

I do think it is a faulty alarm, or bad contacts, from memory, this one was always the one to beep way before the others.

The 9v lithium reads ok, on load, and off load, 9v+
 
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