Battery Hall of Shame 9v Series Winner
xanadu
Posts: 3,347
I got four of these 9v grocery store special batteries. The first one died in my ANR headset in about an hour. I put the second in and it did the same thing. I measured the current draw of my headset at 20ma. For the third one I closely monitored it and thought for sure that my headset had an issue but it never pulled more than 20ma and the battery died just as quick.
So I sacrificed the fourth battery on a dummy load measured at 20ma. 50 minutes later you get the pic below.
That is abnormal right? I don't have any other fresh 9v to test but if memory serves me they should last around 20 hours at 20ma.
So I sacrificed the fourth battery on a dummy load measured at 20ma. 50 minutes later you get the pic below.
That is abnormal right? I don't have any other fresh 9v to test but if memory serves me they should last around 20 hours at 20ma.
Comments
and they state 'ULTIMATE Long Lasting'
wow..
Enjoy!
Mike
*I understand that if I am not completely satisfied, then I have been had. I am over 4. I agree not to consult a lawyer. Please enrol me in your special car insurance scheme - I understand I need sign nothing to make this completely legally binding.
So the more millis or more Amps you use, the fewer Hours you get 500 / 20 =25
Even higher power,UPS batteries 12V 7Ah are rated for 20 hour discharge cycle, with 350mA of current. When discharged with 1C current, capacity drops 30-50%, depending on model.
Only battery which is not suspectible to such capacity drop is lithium battery, plain or rechargeable. They have almost same capacity when discharged 10C, 1C or 0.1C currents.
Jim
But when I went and bought a Seagate 2GB USB harddisk and found out by only opening the box that I had NOT purchased the unit, it was being licensed to me to use and I should keep all the Windows related software on it --- that was a bit too much.
I reformated it to EXT3 file system for Linux as a USB boot, and dumped all their surprise package of legal nonsense.
If Seagate wants to void the 'contract', they can come and get me in Kaohsiung. I think that I should have at least had a warning on the outside of the sealed box that I was NOT buying the disk and that it was a Windows only license to use. Putting it inside the box disallowed an informed purchase.
But the truth is that in Taiwan, nobody really cares what Seagate or Microsoft is trying to do. We all know that we are too far away to be bothered.
Off-brand batteries are a rather absurd gamble. And 9V cells are some of the worst performers for providing power. I have a 6-cell AA battery holder with the same snap in as a 9-volt cell and I use that instead.
Only my digital multimeter and digital capacitance meters require actual 9v cells, and those I buy quality brands from the local electronics supply house at a discount.
Are you sure a it was a packet of batteries you bought?
"Everyday" is clearly an attempt to confuse people with "Everready" batteries. That would have been a big red stop light to me. Had I noticed of course.
Marty
Loopy I prefer to use dry cells for this so the 6AA holder is a perfect replacement for the 9v battery box, thanks for that suggestion. Fry's has them in stock too
As far as batteries go, because of the chemicals involved during the manufacturing process, and the chemicals in end product, there are only a few companies allowed to manufacture batteries at all. Most of the time your paying for the label and what's under the hood is all about the same.
I have not seen Alkaline 9V in the dollar store for many years and I bought as many Duracells as I could when RS was unloading them for a buck and change.
Anyway if you buy a battery without a capacity rating you are buying a pig-in-a-poke. Fortunately
secondary cells are normally rated for capacity so you have some form of come-back if ripped-off.
Sometimes you can find a datasheet for a particular battery - always a good sign.
http://www.woot.com/plus/duracell-alkaline-batteries-1?ref=cnt_wp_15
-Phil
Lots of complaints about Kirkland cells leaking at http://www.amazon.com/Kirkland-Signature-1-5V-Alkaline-Batteries/product-reviews/B0015UVOJU/ref=dp_top_cm_cr_acr_txt?showViewpoints=1
I'm still amazed at Duracell's warranty; they sent me $175 for an old camera when cells leaked. Another reason to stay with a brand name.
http://forums.parallax.com/showthread.php/151851-Happy-Ending-to-Leaky-Duracells
Yes, really good point. All batteries come down to just one number - the capacity. How hard can it be?
Unless... they like the confusion, it suits their business model.
Well, erco mentioned Duracell. A few years back I bought a really good rechargeable charger http://www.mahaenergy.com/chargers/ and I decided it was time to change the entire house over to rechargables. So, first step was to run all the rechargeables I had through that charger/analyzer and see what capacity they *really* had. Some were less than 1/10th of what they claimed, and this was with some brand new (but no name) rechargables.
And then I tested some other brands, and Duracell came out on top of the tests. All their rechargeables came in at almost exactly, or a fraction more, what was written on the side of the battery. So I decided to stick to one brand only.
Interestingly, the capacity of duracell rechargeables that was more than many alkalines I tested. So you buy a rechargeable, charge it maybe 3x, and it has paid for itself. The next 500 charges are a bonus. In terms of real cost of energy, sometimes the rechargeable was cheaper than the disposable battery, even with the residual charge in the battery before it was even charged the first time.
Maybe this is a bit nerdy, but the whole family has come on board. We have two plastic bags in the cupboard - "charged" and "flat" and we have maybe 10 or so batteries in the charged bag, so there are always fresh batteries available for anyone who needs them. And when the charged bag gets low, someone tells me and I charge all the flat ones.
http://en.wikipedia.org/wiki/Alkaline_battery
It is odd because doesn't the same doesn't apply to rechargeable batteries?
Yes, but rechargeables have a relatively flat discharge curve up until the end of their capacity - meaning they remain above the cutoff voltage longer.
Better a more educated consumer than another regulation.
It's not hard to have a nominal capacity rating on the battery but it's easier to get away with misleading claims without one, so yes, they do like the confusion.
That's not the only Kirkland product in the news.
http://www.cbc.ca/news/business/costco-s-kirkland-chicken-strips-recalled-over-listeria-1.2582027
This is a little off topic, or maybe not.
I made one of those Joule - Thief boost circuits, its just a coil and a transistor. Claim to be able to light an LED using a dead (0.8 volt) AA battery. It worked! Then I tried to light a 12 volt, high power LED (the 9 element ones from China) using a dead 9 volt battery (8.0volt). It also worked! So I left it on to see how long it would last.
When I came back the bnext day, the 9 volt alkaline battery had burst! I could see the streak of the goo where they dried acros the desk. Kind of cool! Why did this happen? The boost circuit gnerated skies of up to 40 volts, but as the volatge rises, the LED begins to conduct, and bleeds of the pusle before it gets too large. As the battery dies, the frequency of the pulse goes down, but the maginitude of the pulse seems to stay about the same. But why did the battery busts ?
First, the Joule Thief boost circuit draws a LOT more current as the input voltage rises. So it was most likely nearly shorting out the 9v battery. Second, alkaline batteries often corrode through the case when they are discharged down to zero volts due to age or abuse. So I'd guess the 9v battery leaked because it was hot from the joule thief abuse while nearly shorted and prone to corrosion.
Btw. a 9v battery is just a prepackaged 6 cell pack. At 8v it still had most of it's energy left. I'd say 70-80% of the energy was left based on discharge curves I've seen for alkaline batteries.
Marty