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From: Chris Malcolm on 7 Jul 2010 15:06
In rec.photo.digital SMS <scharf.steven(a)geemail.com> wrote:
> On 06/07/10 3:53 AM, Robert Spanjaard wrote:
> While there are rechargeable Li-Po and Li-Ion cells that are the
> physical size of an R6 cell, (14500), the chemistry yields 3.6-3.7
The ones I use have a nominal voltage of 3.7V and a fully charged
voltage of 4.2V.
Warning: none of the above is indisputable fact.
From: Joel Connor on 7 Jul 2010 17:24
On Wed, 07 Jul 2010 12:38:58 -0400, Dave Cohen <user(a)example.net> wrote:
>John Navas wrote:
>> rOn Tue, 06 Jul 2010 13:25:56 -0700, in
>> <4c339148$0$22110$742ec2ed(a)news.sonic.net>, SMS
>> <scharf.steven(a)geemail.com> wrote:
>>> On 06/07/10 6:21 AM, Robert Sneddon wrote:
>>>> In message<i0v9cr01i0r(a)news1.newsguy.com>, J. Clarke
>>>> <jclarke.usenet(a)cox.net> writes
>>>>> There appear to be two "Synergy" battery product lines, one produced by
>>>>> Hahnel in Germany and the other by Synergy Digital in Brooklyn, NY.
>>>>> The Hahnel product appears to be an Eneloop clone while Synergy appears
>>>>> to be importing Chinese-clone OEM-replacement camera batteries.
>>>> The Sanyo Eneloop low-discharge NiMH battery technology is being
>>>> licenced more widely nowadays.
>>> Is it being licensed or are other companies just building their
>>> batteries in a similar manner? What Sanyo did with the eneloop product
>>> is not rocket science--the technology for reducing self-discharge in
>>> Nickel based batteries is not new.
>>> The problem is that same design changes that reduce self-discharge also
>>> reduce capacity, and we were seeing something similar to megapixel wars
>>> with mAH wars. People just got fed up enough with self-discharge that
>>> they were willing to go with eneloop AA cells at 2000mAH versus regular
>>> NiMH AA cells which have up to 50% greater capacity.
>>> While the eneloop, and other low self-discharge cells, solve one of the
>>> major problems with NiMH cells, they still have most of the drawbacks of
>>> AA cells in general, and NiMH cells in particular.
>>> More information is available at "http://misinformedtrolls.com/".
>> Your own website. And another area is which you try to pass yourself
>> off as an expert even though you have no real expertise. Why am I not
>You are missing an important observation made earlier my Mr. Connor. The
>cells are superior to eneloops since they are 1.25v as opposed to the
>measly 1.25v of eneloops.
Normal NiMHs are rated at a base voltage of 1.2v, not 1.25v suggesting a
different chemistry. Yes, there's a range of voltage from full charge to
discharge, but all NiHMs I've bought were rated at 1.2v.
From: SMS on 7 Jul 2010 17:30
On 07/07/10 12:06 PM, Chris Malcolm wrote:
> In rec.photo.digital SMS<scharf.steven(a)geemail.com> wrote:
>> On 06/07/10 3:53 AM, Robert Spanjaard wrote:
>> While there are rechargeable Li-Po and Li-Ion cells that are the
>> physical size of an R6 cell, (14500), the chemistry yields 3.6-3.7
> The ones I use have a nominal voltage of 3.7V and a fully charged
> voltage of 4.2V.
Yes that's correct. The no-load fully-charge voltage of Li-Ion falls to
3.6-3.7 volts quickly under load. One advantage of the Li-Ion batteries
is that the voltage is proportional to the remaining charge so an
accurate battery gauge is possible. With AA cells, the remaining battery
capacity is less clear because it's so dependent on the type of AA cells
NiMH cells have a very non-linear discharge curve while manganese and
lithium non-rechargeables are linear, but with different voltages.
The battery voltage indicator in CHDK is a useful feature but it would
be nice if there was a CHDK feature that let you set the battery type
and mAH capacity and provided a gauge based on that, that used a look-up
table rather than showing a linear percentage based on voltage. Alas
that's a complicated thing to do, and at least what CHDK provides is
better than what Canon provides on AA powered cameras. On Li-Ion powered
cameras the CHDK battery indicator is very good but you want to be sure
to set the voltage levels properly or you'll wonder why a fully charged
Li-Ion battery is only at 90% (with the default setting).
From: John Navas on 7 Jul 2010 21:46
On Wed, 07 Jul 2010 14:30:26 -0700, in
>> The ones I use have a nominal voltage of 3.7V and a fully charged
>> voltage of 4.2V.
>Yes that's correct. The no-load fully-charge voltage of Li-Ion falls to
>3.6-3.7 volts quickly under load. One advantage of the Li-Ion batteries
>is that the voltage is proportional to the remaining charge so an
>accurate battery gauge is possible. ...
Battery Fuel Gauges: Accurately Measuring Charge Level
Abstract: Battery fuel gauges determine the amount of charge
remaining in a secondary battery and how much longer (under specific
operating conditions) the battery can continue providing power. This
application note discusses the challenges presented in measuring the
charge remaining in a lithium-ion battery and the different methods
of implementing a fuel gauge to address these challenges.
Accurately Measuring Charge Level
To determine the available charge in a battery, simple monitoring
methods are preferred. They should consume little energy and should
(ideally) allow one to deduce the charge level from battery voltage.
Such a voltage-only method can produce unreliable outcomes, however,
because no clear correlation exists between voltage and the available
charge (Figure 5). Battery voltage also depends on temperature, and
dynamic relaxation effects can cause a slow increase in the terminal
voltage after a reduction in load current. Thus, purely voltage-based
monitoring is unlikely to provide charge-level accuracies better than
The relative charge level, often called the state of charge (SOC), is
defined as the ratio of residual charge to the battery's charge
capacity. Hence charge flow must be measured and monitored through a
procedure called "coulomb counting." In practice, coulomb counting is
accomplished by integrating the currents flowing into and out of the
cell. To measure these currents with a high-resolution ADC, one
typically connects a small resistor in series with the anode.
You are indeed your own worst enemy.
"It is better to sit in silence and appear ignorant,
than to open your mouth and remove all doubt." -Mark Twain
"A little learning is a dangerous thing." -Alexander Pope
"Being ignorant is not so much a shame,
as being unwilling to learn." -Benjamin Franklin
From: Dave Cohen on 8 Jul 2010 17:20
On 7/7/2010 12:52 PM, SMS wrote:
> On 07/07/10 9:38 AM, Dave Cohen wrote:
>> You are missing an important observation made earlier my Mr. Connor. The
>> cells are superior to eneloops since they are 1.25v as opposed to the
>> measly 1.25v of eneloops.
>> Sanyo didn't need rocket scientists to claim a unique process, just a
>> patent (which I assume the have).
> Getting a patent is easy. Defending it is the hard part.
> The cause of self-discharge in Ni-Cad and NiMH batteries has been well
> known since they were first invented--the plates swell and press against
> the separator. You can reduce the swelling by depositing less active
> material on the plates, but this reduces capacity. The goal in NiMH
> batteries was always higher capacity. Sanyo made a decision to reduce
> the capacity and decrease the self-discharge. I wonder if anyone is
> actually paying them royalties or licensing fees for this.
>> While I'm posting, will someone tell me how I can determine who owns or
>> doesn't own a camera in this group.
> A P&S or a D-SLR?
I won't question your comments on how these things are made since I
don't know. However, using the same capacity rating (around 2100 mah),
eneloops clearly outperform the normal NiMH of same capacity for shelf
life, so I assume they are doing something different. I normally shoot
very infrequently and I've left cells in the camera for over a year.
When I first got the eneloops I ran them down in a Canon A95 over a
three week period and got an amazing 600+ shots (very little flash, very
little lcd use). After that I got 300+ within a year, after that I
didn't keep track (after that the A95 went belly up and I'm back to my
When the eneloop first came out, I did read they had been licensed to
others. As for asserting/defending patents, that's how lawyers make a
living (and a very good living at that).