Capacity of battery??
Archiver
Posts: 46,084
Dear all,
BS2 needs 5.5-15V, 8mA to run, wat's the battery capacity (mAh)
required to run it continuously for at least 168 hours?
have a nice day!!
BS2 needs 5.5-15V, 8mA to run, wat's the battery capacity (mAh)
required to run it continuously for at least 168 hours?
have a nice day!!
Comments
of course this in an optimistic value, the actual battery should have
a higher capacity than this, may be something close to 2Ah as it has
to provide a sufficiently high voltage.
There are means to reduce power consumption: by software and/or by
using a BS2pe.
regards
Adrian
This is rather simple, but has a few additions to consider. We use Li-Ion
polymer batteries to run the micro devices with GPS modules. If you just
take for example two 18650 Li-ion batteries in series (2000 maH per
battery), that has avg voltage 3.7 v x 2=7.4 volts, and divide 2000 mA by 8
mA and just for fun assume that these batteries are 98% efficient, you will
get about 245 hours of use before the battery needs to be recharged. the
neat thing about the lithium batteries is that the drop off is almost a
vertical line where as Ni Cad or similar batteries drop of like a sliding
board with a slow, long slope and then quits. Lithium also gives you a
larger mAh per square mm and is very cost effective. i am importing these
batteries from Korea and China in small quantities for about $3-$10.
battery depending on mAh. The charger is a single TI chip which works like
a champ and charges up to two batteries in less than 3 hours. Another
example is our wrist worn GPS unit. It draws about 30 mA and we use a 750
mAh LI-Ion battery with the unit receiving and logging once every minute.
The battery has been tested and lasts over 36 continuous hours before it
needs charging. We let it sleep a little so the numbers are a little off
The battery is tiny, 14 mm. d x 48 mm l. Just as an example. I see a 1500
maH battery that will give you around 188 hours of use (continuous duty).
Check out some Li-Ion specs.
mike m
Original Message
From: <800205015763@n...>
To: <basicstamps@yahoogroups.com>
Sent: Wednesday, January 29, 2003 3:15 AM
Subject: [noparse][[/noparse]basicstamps] Capacity of battery??
> Dear all,
>
> BS2 needs 5.5-15V, 8mA to run, wat's the battery capacity (mAh)
> required to run it continuously for at least 168 hours?
>
> have a nice day!!
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
>
for 6v at 2500mAh.
Unfortunately not. You could hook up 4 1.5V cells in parallel and
have 1.5V at 2500 mAh or you could hook up them in series and have 6V
at about 625 mAh - there is no free lunch.
In your case you would need e.g. 16 1.5V cells, 4 stacks of 4 in
series for 6V at 625mAh totaling up to about 2500mAh. Note that these
are all theoretical figures. No real battery is 100% efficient and
not all cells are the same. Furthermore cell voltage drops during use
of a battery/accu. The real thing is not easy to calculate. You will
have to experiment and be ready for reasonable overdimensioning.
Regards
Adrian