Re: [SARES] on rechargeable batteries

Here is the information, as provided in the initial announcement about 
the battery purchase.

> /
> HI folks,
>  
> Here is the battery group order the I have worked out.  The AA NI-MH 
> batteries come in groups of 4 with a case.  They are 2600 mAh 
> batteries from *Tenergy*.  The price is 4.25$ for 4 and 4.60$ with tax.
>  
> The chargers are T-1000 smart charger that charges up to 4 batteries 
> 2-3 hours.  It also charge using the cigaret adapter in your car.  The 
> price is 8.40$ and with tax it is 9.10$.
>  
> If we get enough people wanting AAA batteries they will be 3.22$ 
> including tax for 4 900 mAh batteries with a case.
>  
> Please send me an email with your order by May 30.  I will need the 
> money by June 7.
> /


Tae wrote:
> Ralf,
>
> What is the brand of these AA batteries and charger?  Is there a web 
> site that I can read about them?
>
> Thanks Ralf for coordinating all this!
>
> Tae
>
> ----- Original Message ----
> From: Andreas Ott <andreas@naund.org>
> To: Ralf Erickson <wa6cqa@sbcglobal.net>
> Cc: SARES LIST <sares-list@sunnyvaleares.org>
> Sent: Wednesday, May 31, 2006 9:33:23 AM
> Subject: [SARES] on rechargeable batteries
>
> Hi,
>
> I am a huge friend of rechargeable batteries but would like to point out
> that they are not always a drop-in replacement for alkaline batteries. It
> is important to understand the differences in battery chemistry so that
> you can get the most mileage out of them.
>
> On Sun, May 28, 2006 at 03:40:53PM -0700, Ralf Erickson wrote:
> > Here is the info from Seth:
> ...
> > For those that missed my email on this subject let me give you a short
> > version.  This is from lessons from Katrina.  If we have a large
> > earthquake we may be operating 2 or more weeks.  If that happens we 
> will
> > probably not be able to get more AAA batteries so we must make the ones
> > we have last.  So my idea is that I should have enough NI-MH batteries
> > to last 2 days.  Also I should have the chargers to be able to charge 1
> > days worth at a time so I am not changing them during the time I am
> > trying to sleep.  >From experience I should be able to run all day with
> > 2 sets for my radio of fairly heavy traffic.  This works out to 12
> > batteries a day and 24 for 2 days.  Also I should have 3 chargers.
>
> When homebrewing rechargeable battery sets for your radio, please keep
> in mind that the NiCd and NiMH cells have a nominal voltage of 1.2V
> per cell versus the standard 1.5V of Alkaline AA cells. Most of the AA
> alkaline battery holders for HTs that I have seen are 'designed' and
> have connections for the voltage of multiple 1.5V cells, i.e. 6 cells
> will produce 9V in the alkaline pack but only 7.2V in the NiMH pack
> configuration. So please make sure that your radio can accept rechargeable
> batteries in the regular alkaline battery holder. The more cells you have
> in your battery holder the bigger the difference in voltage between the
> two battery types.
>
> It is also well known that charged NiMH cells have a high discharge rate
> when stored (compared to other cells). One needs to keep this in mind
> when storing fully charged batteries for emergency communications needs.
> Reports are that it is best to charge them full right before you use
> them but in an emergency the power might be already out when you need
> the batteries. Always use a charger that is desinged to handle the
> battery type.
>
> I have been using rechargeable AA cells with limited success in a digital
> camera that was designed for alkaline cell voltage. The camera always
> thinks it's low on battery as the voltage is only 4.8V over the 4 cells
> where it would expect 6V if it had alkaline batteries. To the contrary, my
> MP3 player has a setting in its software menu to switch between alkaline
> and rechargeable battery to calibrate its battery low indicator. It runs
> very well on NiMH cells.
>
> 73, andreas  de K6OTT
> +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
> SARES members mailing list: <sares-list@sunnyvaleares.org>
> For help with (un)subscription send e-mail to <majordomo@athm.net>
> ------------------------------------------------------------------------
>
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.1.394 / Virus Database: 268.8.0/353 - Release Date: 5/31/2006
>   

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
SARES members mailing list: <sares-list@sunnyvaleares.org>
For help with (un)subscription send e-mail to <majordomo@athm.net>