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Re: The secrets of eneloop batteries
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Sadly, Panasonic may not exist in a few years, the way their business is
going.

Re: The secrets of eneloop batteries

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   Aren't they classed as 'Too big to fail'?

Re: The secrets of eneloop batteries
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Possibly.  We'll see.

Re: The secrets of eneloop batteries
On a sunny day (Sun, 23 Sep 2012 18:27:19 -0400) it happened "Michael A.

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No, that was the US.
:-)

Re: The secrets of eneloop batteries

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   When were they made?  Most of what I see for sale is the new
labeling.

http://panasonic.net/energy/eneloop /

Re: The secrets of eneloop batteries
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They're good.  I've had equal experiences with RayOVac's "Hybrids".
Unfortunately it's a moving target--they keep changing the name.  I
think they're calling 'em "Precharged" now, or "Platinum" or
something.

I *really* like the PowerGenix NiZn cells I have.  They're fragile,
die if you let 'em run too low (be sure you buy them charged, or
they're ruined), but the higher terminal voltage works a lot better in
many devices.  I don't expect nearly the advertised number of charge
cycles, but even 10 cycles more than pays for them.

--
Cheers,
James Arthur

Re: The secrets of eneloop batteries
On a sunny day (Mon, 24 Sep 2012 07:18:23 -0700 (PDT)) it happened
snipped-for-privacy@yahoo.com wrote in

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Hey, thank you, did not know about that.
Will probably get some, more capacity, more voltage, and even cheaper here than
NiMH
The charger I will program myself :-)
  http://www.powergenix.com/?q=nizn-charge-procedure
Do you have to change low charge cutoff voltage from 1.0 or 1.1 to 1.3 V?

Re: The secrets of eneloop batteries
On a sunny day (Mon, 24 Sep 2012 07:18:23 -0700 (PDT)) it happened
snipped-for-privacy@yahoo.com wrote in

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Hey, thank you, did not know about that.
Will probably get some, more capacity, more voltage, and even cheaper here than
NiMH
The charger I will program myself :-)
  http://www.powergenix.com/?q=nizn-charge-procedure
Do you have to change low charge cutoff voltage from 1.0 or 1.1 to 1.3 V?

Re: The secrets of eneloop batteries
On a sunny day (Mon, 24 Sep 2012 07:18:23 -0700 (PDT)) it happened
snipped-for-privacy@yahoo.com wrote in

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Upon reading the datasheeets:
self discharge is to 60% in 28 days!
Capacity is a lot lower than NiMH too.

Eneloop is better than that in 5 YEARS.

So that is a no-no.

Re: The secrets of eneloop batteries
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The actual self-discharge is a lot better, by my measurements.  The
main problem is, like LiIon, the cells die (go hi-z), seemingly if you
ever let them go too low.

These guys talk about some of the challenges (posts #1, #20):
  http://www.candlepowerforums.com/vb/showthread.php?281051-Overdischarge-o =
f-NiZn-Cells

Post #20 says that zinc just won't ever work in a rechargeable, that
charge cycles quickly amplify infinitesimal defects.

The cell is nearly fully discharged at 1.4V, so yes, that gives you
fairly little low-battery warning in devices set for alkaline cells.

I like them in devices that don't work well on NiMH voltages.  My
favorite camera reads "Battery Low" on freshly charged NiMH, and shuts
down long not long after.  It barely works at all on expensive
alkalines, works great on NiZn.

LED flashlights with converters work better on the higher voltage, as
it greatly reduces the i^2*r loss in the battery connections &
circuit.  (It's surprisingly difficult to get 1A @ 1.2V efficiently.)
One of my handiest lights uses a single AA, and works tremendously
better on 1.7v than 1.3v.

So, there are some limits, but compared to $0.25/ AA alkaline cells
(that don't work in the camera), these have provided excellent service
for two years so far, at a cost of $2/cell.

--
Cheers,
James Arthur

Re: The secrets of eneloop batteries
On a sunny day (Tue, 25 Sep 2012 04:27:39 -0700 (PDT)) it happened
snipped-for-privacy@yahoo.com wrote in

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Yes, I agree with most, some remarks:
The eneloops have a slightly higher voltage too, and that makes my Canon camera
a bit more 'ready to shoot'.

The thing that really had me thinking was that I found a site that sells NiZn,
and it
did not mention mAh, but mWh.
At first glance I thought this was a printing error, but then, reading the
datasheets,
found that is is deliberate.
The mAh is MUCH lower for an AA than for a similar recent NiMH, so they mention
mWh,
as that is, with 1.6 V cell voltage, a bit more (but still lower than a NiMH).

But for the consumer, who looks at capacity, and is used to mAh,
and sees mWh, will he / she fall for the high number, or at least
not be turned off by the low number (that mAh would have had).
So is this fair practice?
Very difficult to say, as you COULD reason that NiZn will indeed last longer
before dropping to 1.1 or 1.0 V
where niMH equipment (I use 1.0 myself) switches off.
But then if that kills the battery what good is it?
So that is not right in my view, and other reason to not use them.
I like the idea of NiZn, simple, but they have some way to go before they become
competitive it seems.

Re: The secrets of eneloop batteries
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The NiZn cells deliver ~1,500mAh x 1.7V nominal discharge voltage 3D%
2,550 mWhr.
A typical low self-discharge NiMH is ~ 2,000mAhr x 1.25V 3D% 2,500mWhr.

In my devices NiZn lasts a lot longer than NiMH because the switchers
are so much more efficient at the higher input voltage.

So, rating in mWHr seems very fair.

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They're certainly environmentally attractive.  Hopefully they'll get
refined/perfected over time.

--
Cheers,
James Arthur

Re: The secrets of eneloop batteries
On a sunny day (Tue, 25 Sep 2012 17:07:06 -0700 (PDT)) it happened
snipped-for-privacy@yahoo.com wrote in

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Hey, for the case where a SWITCHER is used, you are right.
But Mr consumer may put it in a flashlight,
and use it until it looks like a glowing nail....
Those wire type bulbs behave a bit like a current source too.

Re: The secrets of eneloop batteries
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You mean fire-bottles?  (Do people still have those?)

The NiZn isn't gonna work in those.  1.8v isn't good for them!

--
Cheers,
James

Re: The secrets of eneloop batteries
On a sunny day (Wed, 26 Sep 2012 06:19:53 -0700 (PDT)) it happened
snipped-for-privacy@yahoo.com wrote in

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Never heard that expression,
googling for it shows it can mean anything from Molotov cocktail
to fire-extinguisher..
 http://quick.aero/sterling/blog/how-to-ship-apu-fire-bottles-as-non-explosives /

I actually have 2 flashlights with indescandent bulbs,
both run on 4 duracells,
in once you can select between LEDs and indescandent.
The duracells have been in once of those for more than 5 years I think.
The other one had a sealed lead acid rechargable that I killed by accidently
leaving that light on (I think), replaced it by 4 AA.


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Na, ya, bit more light :-)


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Re: The secrets of eneloop batteries [how to use multicell accumulators optimally...]
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...
...

Hi Jan

The reason for the low voltage and high internal resistance it that your
battery equipment:
* discharge of one or more cells to a too low voltage (even reverse
voltage!)
* the batteries has different characteristics

To get more life and easier charging from 2+ cells of LSD-NiMH (or
LiFePO4) you need a accumulator controller with each accummulator
packet, that monitor each cell.

Battery management system:
http://en.wikipedia.org/wiki/Battery_management_system

E.g. like this - but not for LSD-NiMH - only for Li-ion (not LiFePO4):
http://www.linear.com/product/LTC6801
http://www.linear.com/product/LTC6802-1

You could use a ultra low power microcontroller for BMS or stack fault
monitoring?

/Glenn

Re: The secrets of eneloop batteries [how to use multicell accumulators optimally...]
On a sunny day (Sun, 23 Sep 2012 10:18:03 +0200) it happened Glenn

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Looks like a nice chip,
but incorporating it in my Canon camera will be a challenge ;-)
I use the eneloops mainly for consumer stuff I have.
I ran some compare test this morning,
trying to get 160 mA charge current into a as 'defective' marked AAA
needs 1.9 V, while only 1.6 V owith a non defective AAA.
So it seems the observation that Ri is higher than normal is true.
My conclusion is that the high Ri defective onces can still be used in low
current applications like my mp3 player, but likely not in the camera (flash
draws a lot), and can only be charged from the lab supply.
From now on, (blaming the Duracell charger? but it works fine with Duracells)
I will charge all eneloops with the lab supply, it is fully programmable any
ways,
I can even control it from a script on teh PC if need be.
  http://panteltje.com/panteltje/pic/pwr_pic/index.html
:-)



Re: The secrets of eneloop batteries [how to use multicell accumulators optimally...]

The ENELOOP chargers have an odd flashing LED scheme to report on
charging. You can google to get the decoder ring. But I believe it has a
discharge before charge mode. I triggered it once. I suspect there is
some poing where Sanyo didn't want to just top off the battery and
believed a dischrage before charge would be more appropriate.

When it comes to rechargables, it is best to keep the batteries
associated for one device grouped together. That way it is most likely
that they will be discharged to the same amount.

Some of my devices have a programmable battery lower voltage limit.
Other have a program mode for alkaline or NiMH. It is best to not mix
and match those batteries with devices that don't protect the batteries,
since the devices with programmable cutoffs have probably treated the
batteries better.

I don't have any flashlights that aren't LED anymore. [Even modified the
old maglights for LED.] But a flashlight with a filament bulb will most
certainly overdischarge a second cell.



Re: The secrets of eneloop batteries [how to use multicell accumulators optimally...]
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I have Enloop batteries.  I bought one of the early packs with the
charger and liked them so well I bought another, both at Costco.  My
main problem is keeping track of all the batteries.

They have saved me buying any more disposable cells for the last four
years I believe.  I guess I still use disposable cells in my clocks and
a couple of lights I use on the kayak.  I even keep a set of four in my
kayak bag in case one of my powered units didn't get charged and I have
to swap them out.  So far they have only been loaned to other paddlers
who's units with disposable cells have run out of juice.  Keeping all my
units charged is a little work, but I never run out of power on the water.

Rick

Re: The secrets of eneloop batteries [how to use multicell accumulators optimally...]
On a sunny day (Mon, 24 Sep 2012 14:26:09 -0700) it happened miso

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Thanks, yes that idea of doing some discharge may really help,
tried it last night,
Almost like those eneloops get used to low discharge current,
need to have a bit of a big one every now and then.

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