Video showing heavy flour in AA batteries: any way for layman to test NiMH batteries?

Assuming this isn't a joke...

I don't believe AAA cells can have 2100mAh capacity. So that's a problem.

What ever happened to buying OEM batteries?

If there's a battery store near (such as Interstate), try it.

I wouldn't be surprised if the video is a practical joke. A friend of mine sent me a link that showed that what is inside the large 6 volt lantern batteries are just a whole bunch of AA batteries. I told him that the video was crap. He didn't believe me and went out and bought one of these batteries and pried the bottom off. Just like I told him there were 4 large cells in the thing, not a whole bunch of AA cells. He did call me to tell me I was right and say he felt pretty silly. Eric

I suppose it may well be a joke, look at

OshOXcSkDA and you decide: It even warns viewers off the seller and says th ey refused to refund ALL of the money paid.

Yes, that occurred to me as well when I saw the video but there seem to be lots of them on ebay and I wondered what they really were and how to test t hem if they do work on arrival and aren't completely fake. There IS a majo r leap of faith between something marked 650MAH and an offer of 2100 MAH

I didnt know that Interstate made AAA batteries but how do they compare in price to the ones from Virginia on ebay? Assuming the ones arent just usel ess

The following aren't cheap, but at least they're from a major manufacturer:

You might also try Thomas Distributing. I buy all my rechargeables from them.

Thomas Distributing show that they distribute Eneloop NiMH batteries which I wonder about in OP.

I did check with Panasonic and they say they recommend NiMH so I assume I s houldnt be using NiCAD and cant recharge Lithium ones. So how far can I pu sh the milliamps realistically? And, again, is there any way of testing wha tever I do end up with please?

I suppose I can just charge them along with the present batteries and leave them next to each other for a few days and see how long they last before t hey die. But that says nothing about how long any batteries I get are going to LAST?

Now I have seen a report that for cordless phones, you should use special l ow discharge batteries and that ordinary NiMH ones will just die if left of f the base So i am not sure I can even perform the test I thought obvious! The low discharge ones say they are something over 900MAH.

There seem to be lots of sellers specifically targeting their sales towards Panasonic cordless phones. I wonder if there is any difference or if "low discharge" means anything (in practical terms)?

snipped-for-privacy@whidbey.com

** Ever pried open a 9V alkaline battery?

There are six cells inside ( LR61s) smaller than AAAA.

... Phil

"Amanda Riphnykhazova"

Now I have seen a report that for cordless phones, you should use special low discharge batteries and that ordinary NiMH ones will just die if left off the base

** Total bollocks.

There seem to be lots of sellers specifically targeting their sales towards Panasonic cordless phones. I wonder if there is any difference or if "low discharge" means anything (in practical terms)?

** None.

Cordless phones are normally left on constant charge.

Low discharge cells ( ie Eneloop) have advantage when the device is left with no use or charge for months on end.

Like a digital camera or torch often is.

.... Phil

Yeah, interestingly low discharge is also described as low self-discharge, indicating that they will discharge THEMSELVES if left alone and turned off ."Like a digital camera or torch often is" It doesnt seem to say anything a bout whether they will discharge any more than other batteries if left 'on' in a working phone. Although the description implies it strongly, doesn't it!

It doesn't, because you're presumably leaving the 'phone on the charger base when it's not in use.

I've owned cordless phones with both nicad and NiMH batteries, and had no problems with either. You're worrying about something of no importance.

When in use, a battery discharges according to how much current is drawn. Whether it's a low-self-discharge battery doesn't matter -- unless you're drawing a tiny bit of current over a long time. Common sense.

"Amanda Riphnykhazova"

Yeah, interestingly low discharge is also described as low self-discharge, indicating that they will discharge THEMSELVES if left alone and turned off.

** Low self discharge implies the opposite.

The self discharge of regular NiMH cells is quite high compared to Alkaline cells - leave them for a few weeks to a couple of months and most of the energy is gone.

IIFC, Eneloop claim up to 12 months with 80% retention.

Neither of which has any bearing when used with cordless phones.

.... Phil

Sure. No problem. Just short the terminals and the internals will rapidly be revealed: Well, to be honest, the battery was probably a counterfeit.

More: Note that a cell battery (LR8D425) is the same diameter as an LR61 cell, but is 3.5 mm longer.

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Yes. I use a West Mountain Radio CBA-II analyzer:

An NiMH cell discharge graph will look something like this: The 2300 ma-hr cell was only good for 2000 ma-hr. However, there's a catch. I ran the test with a rather fast high current 1C discharge at

2.0 and 2.3 amps respectively. You'll get results closer to the advertised capacity if you use C/10 discharge rate. However, if you really want to impress your friends and accomplises, run it at C/100 discharge rate, and you'll get some really impressive capacity numbers.

Eneloop are good batteries. There are competative low self-discharge batteries that are just as good if you want to save money. The catch is that Eneloop batteries do not like to be fast charged. Sanyo sells a slow charger that works just fine. Though it is possible to charge an eneloop battery in a "Quick Charger", it is not recommended. We recommend charging eneloop batteries in a NiMh charger that is 2 hours or more. Charging eneloop batteries in a "Quick Charger" can reduce the overall life of the battery. My guess(tm) is that you used a fast charger, and killed the cells.

Also, note that there are different types of Eneloop cells: 1500 times rechargeable eneloop battery (2nd generation) has a dark gray cover around the positive electrode and a crown logo on the side. HR-3UTGA (AA) / HR-4UTGA (AAA). 1000 times rechargeable eneloop battery (1st generation) has a white cover around the positive electrode and there isn't a crown logo on the side. HR-3UTG (AA) / HR-4UTG (AAA).

--
Jeff Liebermann     jeffl@cruzio.com 
150 Felker St #D    http://www.LearnByDestroying.com 
Santa Cruz CA 95060 http://802.11junk.com 
Skype: JeffLiebermann     AE6KS    831-336-2558

Originally, those 6 volt lantern batteries were made up of "G" cells (same diameter as "D" but taller). More recently, I've come across some that have "D" cells inside, and no marking on the outside to give a clue.

But here's one: If there are "G" cells inside, the thing will balance over the middle when laid on the side, but if it has "D" cells, it'll be bottom-heavy.

Isaac

Depends on how you use them. For the same chemistry, the only reasonable way to increase the mA-Hr capacity is to put more electrode inside, and that means using a thinner insulator between the plates. A thinner insulator means a higher leakage, and so a faster self-discharge.

So the only way you're likely to actually *get* 2100 mA-Hr out of those cells is if you use them a lot. If what you mostly do is let the device sit around, the cells will be empty when you need them despite the higher capacity.

As a personal example, when I used regular NiMH cells in a little camera I carried around "just in case", it was nearly "empty" almost every time I wanted to use it. And the spare cells I carried would be dead, too. Changing to Eneloop cells, which had a lower mA-Hr capacity, gave me a camera that was always ready to go, even after a couple or three months of sitting around. And when the in-use cells finally did go empty, the spares were still nearly full despite having been charged at the same time.

Isaac

Al Dunlap

Self-discharge is what a battery does to lose charge while just sitting there. A good LiIon loses about 10% of its charge quickly, then loses very little going forward.

My Sennheiser Pro rep told me they don't recommend using Duracell because they don't put enough electrolyte in the cells. They now ship with Energizer.