D-Cell mAh: lithium vs NiMH vs regular alkaline

The largest chargeable battery I have seen in a "D" cell was a rating of

4,000 mAh. This would be 4 Ah. This battery type was an industrial rated battery primarily for running portable lighting equipment, and communications equipment. The standard "D" cells that I see are rated at 2,000 mAh. Maybe the battery you saw is really rated at 1,100 mAh, and they made a printing error?

Take note that most of these chargeable batteries are rated at 1.25 to

1.35 Volts. They are not usually rated at 1.5 Volts. If you are building a pack to run 12 Volt equipment it would be best to use 10 of these battery types in series. We have also built packs with 16 of these batteries in series and put an efficient high current capacity voltage regulator on its output to regulate the output voltage down to 12.5 Volts. Some customers asked for 13.8 Volts to be equivalent to the same voltage that can come from the average automobile.

If you want to have more current, you can make up combinations of series and parallel configurations with these batteries. If we put three sets in parallel in order to have three times the current capacity. When this is done, then portability becomes another issue.

The rating of 11,000 mAh for a single "D" cell sounds very high, or this is battery type I have not seen yet!

--

Jerry G.
======

"Thomas G. Marshall"
 wrote in message
news:u8f9d.3534$4b.2817@trndny09...

Questions.

1. I've found online a NiMH D-Cell boasting 11,000 mAh for $9.  Can that
be
true?

2. The few Li-ion in D-Cell config I've found have pathetic milli amp
hours.
Are there any that will last a long time in something like, oh, a baby
swing
and/or flashlite?

3. I know that the unused shelf-life of NiMH and cads are pretty bad.
But
what of the lithiums?  This is important because I'm interested in
flashlight usages too.

Are there any good pointers to D-Cell rechargables (not the old zincs or
lead-acid's)?

Inteded uses:

        Baby swing
        Flashlights
        Radio

4. I know that a regular D-cell (and others) are 1.5 V.  Is there a
"under
load" consideration that changes specifications for that?  What are the
amps
of such things.  I understand the concepts of volts, amps, amphours,
etc.,
but do not understand them as they relate to batteries.  Furthermore
I've
read that the rechargables typically don't quite reach the 1.5 voltage.


Thanks!

Jerry G. coughed up:

(same as first battery)

The following has them up to 9000mAh, but over 10x the cost of the others!

--
It'salwaysbeenmygoalinlifetocreateasignaturethatendedwiththeword"blarphoogy".

I haven't seen any 11,000 mAh NiMh batteries, but I have seen

8,000 mAh 'D' cells for 9 or 10 dollars.

A standard 'D' alkaline cell will be about 16,000 mAh and has a long shelf life. Alkalines are probably better for the radio if you don't play it all day long. Same goes for the flashlight if you don't use it much.

I hear recharable Lithium cells have a very long shelf life (charged) but they may blow up if overcharged. I think the capacity is about the same as ni-cads.

-Bill

Live and learn! I have never seen a "D" battery at 11,000 mAh.

The largest that the suppliers I deal with can supply is at 4,000 mAh.

Jerry G. ========

Jerry Greenberg coughed up:

1. Please, if you want to top post, I don't have a real issue with it as long as others in your quote havn't bottom posted already. Throwing a top post on top of a buch of bottom posts makes a huge MESS.
2. Did you see the links to the 11,000 mAh's I posted earlier?

--
"His name was Robert Paulson. His name was Robert Paulson. His name was
Robert Paulson..."

Bill Bowden coughed up:

...[thwack]...

Ah ha, thanks! Are they all about the same?

My informal tests between energizer (not e^2) and duracell in the gym powering my old sony walkman (an excellent low power consumption tape player by the way) showed me running for OVER A MONTH of EVERY DAY of OVER AN HOUR A DAY on 2 AA's. No, I am /not/ kidding. Please don't send the cookie truck, I am not crazy either. :) The duracells gacked after a week or so.

I asked a duracell spokesman about this and he said that it's possible: the unadvertised skinny within their (duracell) company is that duracells last longer on multiple very short term usages than energizer, and that energizer lasts longer for sustained durations.

HUH? What have you guys found?

...[rip]...

--
"His name was Robert Paulson. His name was Robert Paulson. His name was
Robert Paulson..."

A high density 'D' ni-cad is 4000 mAh, but a high density NiMh is

8000 mAh. 4000 mAh NiMh 'D cells are actually a samller 'C' cell inside a 'D' package. Lots of air inside.

-Bill

of

rated

at

At

you will see 7000 and 8000 mAh rechargeable D cells.

[snip]

this

I would say that 11,000 isn't unheard of.

message

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or

the

voltage.