From: Allen on
SMS wrote:

<snip>
>
> This is what all the experts say, though not for the reasons you stated,
> other than the "mixing up" reason which can be worked around with a
> little effort.
>

Names, please, and credentials which show that they are truly experts on
rechargeable battery design and use.
Allen
From: Allen on
SMS wrote:
Add to my post of a couple of minutes ago re identification of "experts":
AND are not employed by a company that makes either type of battery.
Allen
From: nospam on
In article <467ff020$0$27162$742ec2ed(a)news.sonic.net>, SMS
<scharf.steven(a)geemail.com> wrote:

> There are inexpensive chargers which charge each cell individually.
> While the chargers with an LCD that indicates the level of each cell may
> be interesting, they really are unnecessary.

the only thing unnecessary are your constant rants about batteries that
are full of half-truths.

> > Stick either with Lithium AA or Li-ion.
>
> This is what all the experts say, though not for the reasons you stated,
> other than the "mixing up" reason which can be worked around with a
> little effort.
>
> The actual reasons to avoid NiMH if possible are:
>
> -High Self-Discharge Rate

eneloop

> -Lower Number of Charge/Discharge Cycles

lithium-ion batteries degrade whether they are used or not. if the
device does not see constant use, then the li-ion device will have the
lower number of cycles, because the battery will be dead.

> -Lower Energy Density by Weight and Volume

true, but for most devices it is an exceedingly minor issue. take two
almost identical cameras - the nikon coolpix 990 and nikon coolpix 995.
the 990 took aa batteries and the 995 took a lithium ion battery. the
number of shots per charge was approximately the same for both and the
990 was only slightly heavier (barely even noticable), mainly due to
the use of more plastic in the 995. in other words - it doesn't matter
very much.

> -Inconvenience of charging and swapping and keeping track of multiple
> packs of multiple cells

it is not as big of a deal as you make it out to be. i guess if someone
had a crappy camera that had poor battery life and regularly shot
thousands of pictures without being near an outlet, it might be an
issue.

> -Poor Cold weather performance

i can afford heat.

> -Lower reliability of devices that use them

nonsense. where do you come up with this garbage?

> -Lower reliability of batteries over long periods of non-use

nonsense. lithium-ion batteries degrade whether they are used or not.

> -No protection circuitry

they don't *need* protection circuitry. improper charging does not
cause an explosion.

> -No accurate charge level indication in device is possible

it is very possible, just not needed.
From: Ron Hunter on
SMS wrote:
> GMAN wrote:
>
>>> But here's a list:
>>>
>>> -High Self-Discharge Rate
>>> -Lower Number of Charge/Discharge Cycles
>>> -Lower Energy Density by Weight and Volume
>>> -Inconvenience of charging and swapping and keeping track of multiple
>>> packs of multiple cells
>>> -Poor Cold weather performance
>>> -Lower reliability of devices that use them
>>> -Lower reliability of batteries over long periods of non-use
>>> -No protection circuitry
>>> -No accurate charge level indication in device is possible
>>>
>>
>> There is enough bullshit above to start a fertilizer farm!!!!
>
> LOL, maybe you'd like to point out anything there that isn't true.
> Didn't think so.

I assume the comparison is between Lithium Ion and standard NiMH
batteries. If so, only the second item would be at issue. Most Lithium
Ion batteries have a use life of about 3 years, regardless of number of
charges. I have NiMH batteries that are older than that, and still work
well.
Just HOW you use, and recharge, the batteries is more important to use
life than the chemistry.
From: SMS on
Thomas T. Veldhouse wrote:
> SMS <scharf.steven(a)geemail.com> wrote:
>> There are inexpensive chargers which charge each cell individually.
>> While the chargers with an LCD that indicates the level of each cell may
>> be interesting, they really are unnecessary.
>>
>
> But very useful! I rate all my batteries by capacity and then put the
> batteries that are the closest in capacity together with each other in series
> in the same device [if they are in parallel it won't matter as the voltage
> will drop properly]. With the top chargers, you can rate capacity at the load
> of your choice [i.e. discharge at 1.0A] so that the ratings most track your
> usage pattern.

This is a good idea, though you realize that very few people are going
to ever do something like this, it's just too much work.

> Keeping batteries of similar capacity together helps avoid the
> issue of polarity flips that can occur when one battery goes dead in a series
> prior to others.

This is true, but if you don't continually completely discharge the set
of batteries in the camera, you won't get a polarity flip in the first
place.

You do point out another disadvantage of NiMH batteries that I'd
neglected to include in the web site, the problem of polarity reversal
of one or more cells in a pack. I've added that to the site.

Steve
http://batterydata.com