Opinions on Digitor alkalines?

[eug k]

hi,

What do you guys think of Digitor Exxtra alkalines - the ones you
get in packs of 20-40 at tandy/dse? Are they up to par with the
big brands? Eveready, Energizer (always thought they were the same
company!), Duracell?


thanks


--
removethis@optushome.com.au is a valid email address. Don't remove anything!

 

[Trevor Wilson]

"eug k" <removethis@optushome.com.au> wrote in message
news:bm4shl$lb8$1@bunyip.cc.uq.edu.au...

hi,

What do you guys think of Digitor Exxtra alkalines - the ones you
get in packs of 20-40 at tandy/dse? Are they up to par with the
big brands? Eveready, Energizer (always thought they were the same
company!), Duracell?

**I use the Kingcells from Jaycar. They seem just as good as the major
brands. Choice did a test on Alkalines some time ago. They found no
significant difference between brands, regardless of price.


--
Trevor Wilson
www.rageaudio.com.au

 

[Phil Allison]

"eug k" <removethis@optushome.com.au> wrote in message
news:bm4shl$lb8$1@bunyip.cc.uq.edu.au...

hi,

What do you guys think of Digitor Exxtra alkalines - the ones you
get in packs of 20-40 at tandy/dse? Are they up to par with the
big brands? Eveready, Energizer (always thought they were the same
company!), Duracell?

** This link compares a number of popular AA cells, including Digitor
Exxtra alkaline.

http://users.bigpond.net.au/vk3yng/batteries/aa_battery_comparison.htm

There certainly is considerable variation - but the Digitors look like
the clear winners on $s per hour.

Note the low 160 mA current used - things may change a lot at say 1 amp.



............ Phil

 

[Phil Allison]

"Phil Allison"

** This link compares a number of popular AA cells, including Digitor
Exxtra alkaline.

http://users.bigpond.net.au/vk3yng/batteries/aa_battery_comparison.htm

** Note that the author has used a ridiculously high cut off voltage of
1.25 volts per cell for his data table.

Even Ni-Cds are not finished until 1.0 volts is reached.

The running time for AA alkalines is 12 -14 hours - not 2 or 3 as
the table wrongly shows.

This works out to be a 2000 mAh rating.

There is also a stupid error with the stated 50 load resistance and
current figures.

Typical ham.





................... Phil

 

[Arpit]

On Fri, 10 Oct 2003 14:29:18 +1000, "Phil Allison"
<philallison@optusnet.com.au> wrote:

"Phil Allison"

** This link compares a number of popular AA cells, including Digitor
Exxtra alkaline.

http://users.bigpond.net.au/vk3yng/batteries/aa_battery_comparison.htm



** Note that the author has used a ridiculously high cut off voltage of
1.25 volts per cell for his data table.

Even Ni-Cds are not finished until 1.0 volts is reached.

The running time for AA alkalines is 12 -14 hours - not 2 or 3 as
the table wrongly shows.

This works out to be a 2000 mAh rating.

There is also a stupid error with the stated 50 load resistance and
current figures.

Typical ham.


Inspired by this, I think I'll try to do a comparison of my own. Just

a few questions

1. 1 volt cutoff will be suitable?
2. WHat current drain- I can do a few?
3. Should I use a resistor, or a constant current draw, if the latter,
how would that work?
4. ANy other advice so i can avoid wrecking the validity of the
comparison?

.................. Phil

 

[Phil Allison]

"Arpit" <DONTSPAMMEF00Lneko4@dodo.com.au> wrote in message
news:i0gcov405hha3n09ggkdmu45sr4t8ask56@4ax.com...

On Fri, 10 Oct 2003 14:29:18 +1000, "Phil Allison"
philallison@optusnet.com.au> wrote:


"Phil Allison"

** This link compares a number of popular AA cells, including Digitor
Exxtra alkaline.


http://users.bigpond.net.au/vk3yng/batteries/aa_battery_comparison.htm



** Note that the author has used a ridiculously high cut off voltage of
1.25 volts per cell for his data table.

Even Ni-Cds are not finished until 1.0 volts is reached.

The running time for AA alkalines is 12 -14 hours - not 2 or 3 as
the table wrongly shows.

This works out to be a 2000 mAh rating.

There is also a stupid error with the stated 50 load resistance
and
current figures.

Typical ham.


Inspired by this, I think I'll try to do a comparison of my own. Just
a few questions

1. 1 volt cutoff will be suitable?

** For Ni-Cd - not alkaline.

2. WHat current drain- I can do a few?

** Go see the Eveready or Duracell sites - the discharge curves are
all there.

4. ANy other advice so i can avoid wrecking the validity of the
comparison?

** The curves on the above site all seem fine - just look at them.



............ Phil

 

[Mike Harding]

On 9 Oct 2003 23:55:33 GMT, eug k <removethis@optushome.com.au> wrote:

What do you guys think of Digitor Exxtra alkalines - the ones you
get in packs of 20-40 at tandy/dse? Are they up to par with the
big brands? Eveready, Energizer (always thought they were the same
company!), Duracell?

I've been using these for 2 or 3 years in all the normal
household and electronic lab stuff. Prior to that I always
used Duracell. I haven't done any tests but my gut feel is
that they only have about 70% of the capacity of a standard
Duracell (which was 2.5Ah last time I looked). However,
as I used to buy Duracell from the supermarket for about
$1 each and the DSE batteries come out at 65c each they
are better value I think. However if I were going on a few
days bushwalking I would fit Duracells to my GPS.

Mike Harding

 

[Trevor Wilson]

"Phil Allison" <philallison@optusnet.com.au> wrote in message
news:3f861f3b$0$9554$afc38c87@news.optusnet.com.au...

"eug k" <removethis@optushome.com.au> wrote in message
news:bm4shl$lb8$1@bunyip.cc.uq.edu.au...
hi,

What do you guys think of Digitor Exxtra alkalines - the ones you
get in packs of 20-40 at tandy/dse? Are they up to par with the
big brands? Eveready, Energizer (always thought they were the same
company!), Duracell?


** This link compares a number of popular AA cells, including Digitor
Exxtra alkaline.

http://users.bigpond.net.au/vk3yng/batteries/aa_battery_comparison.htm

There certainly is considerable variation - but the Digitors look like
the clear winners on $s per hour.

Note the low 160 mA current used - things may change a lot at say 1 amp.

**The best Alkalines I ever had, came with my old JVC TV set. I used the
remote every day, for 15 years. Although the cells had fallen to around 1
Volt each, the remote still functioned fine (4 cells, you see). They were
branded JVC. I swapped the batteries out, when I gave the set to my mum.


--
Trevor Wilson
www.rageaudio.com.au

 

[gcd]

Hi all,
not sure what you're getting at. The test data compares very well with the
data on energizer.com, particularily given a sample of 1. The load is 50ohm
into a -5V supply, not just the 50 ohm.

See
http://data.energizer.com/datasheets/library/primary/alkaline/energizer/consumer_oem/e91.pdf
and the chart for continous use, only 2 curves there, constant load current
of 250 and 500mA. Cell life to 1.25V looks to be about 2 - 2 1/2 hr for his
150-160mA (at a guess). Then there is the chart at the bottom showing life
for 250mA for 1hr/day giving about 3hr to 1.25V.

And the curve for 1A load shows 10 minute capacity to 1.2V !

The eveready curves and his test data indicate a cell voltage of ~ 1.1V in ~
6 to 8hr at ~150mA.

In all, the test data looks ok to me.

The 2000mAH capacity is to a cell voltage of 0.8V@ 25mA. I'm not sure anyone
uses a 1.5V cell down to that voltage and at that low a current demand.

You may alter his ranking if you chose a slightly lower end voltage but that
depends on your application.

Cheers
Greg


"Phil Allison" <philallison@optusnet.com.au> wrote in message
news:3f86359c$0$4845$afc38c87@news.optusnet.com.au...

"Phil Allison"

** This link compares a number of popular AA cells, including Digitor
Exxtra alkaline.


http://users.bigpond.net.au/vk3yng/batteries/aa_battery_comparison.htm



** Note that the author has used a ridiculously high cut off voltage of
1.25 volts per cell for his data table.

Even Ni-Cds are not finished until 1.0 volts is reached.

The running time for AA alkalines is 12 -14 hours - not 2 or 3 as
the table wrongly shows.

This works out to be a 2000 mAh rating.

There is also a stupid error with the stated 50 load resistance and
current figures.

Typical ham.





.................. Phil

 

[Phil Allison]

"gcd" <

Hi all,

not sure what you're getting at. The test data compares very well with the
data on energizer.com, particularily given a sample of 1.

** I said the data in the curves looks fine.

The load is 50ohm into a -5V supply, not just the 50 ohm.

** That *is* an odd arrangement - BTW the -5 volt source is acting
as a current sink, not a supply.

See

http://data.energizer.com/datasheets/library/primary/alkaline/energizer/cons

umer_oem/e91.pdf

and the chart for continuos use, only 2 curves there, constant load
current
of 250 and 500mA. Cell life to 1.25V looks to be about 2 - 2 1/2 hr for
his
150-160mA (at a guess). Then there is the chart at the bottom showing life
for 250mA for 1hr/day giving about 3hr to 1.25V.

And the curve for 1A load shows 10 minute capacity to 1.2V !

** But nearly 1 hour to 0.9 volts.

The Eveready curves and his test data indicate a cell voltage of ~ 1.1V in
~
6 to 8hr at ~150mA.

In all, the test data looks ok to me.

** The table is misleading.

The 2000mAH capacity is to a cell voltage of 0.8V@ 25mA.

** 2850 mAh is quoted for the Energiser E91 cell.

I'm not sure anyone uses a 1.5V cell down to that voltage and at that low
a current demand.

** 2500 mAh is available at 100mA according to the curves.

My wall clock uses about 150uA and an E91 lasts nearly 18 months to
1 volt.

A torch is quite usable with only 0.9 volts per cell.

So is a portable radio.

So are most small motorised toys.

You may alter his ranking if you chose a slightly lower end voltage but
that
depends on your application.

The author's choice of 1.25 volts is absurd for dry cells - all have
delivered only 25% of the stored energy at at voltage. A Ni-Cd for example
has lost 95% by the time 1.05 volts is reached - hence that is a sensible
end point.





........... Phil

 

[Mainlander]

In article <bm4shl$lb8$1@bunyip.cc.uq.edu.au>,
removethis@optushome.com.au says...

hi,

What do you guys think of Digitor Exxtra alkalines - the ones you
get in packs of 20-40 at tandy/dse? Are they up to par with the
big brands? Eveready, Energizer (always thought they were the same
company!), Duracell?

If you have data that shows amp hour ratings this will give you some of
the answers.