DIYbanter - View Single Post - Making a portable battery pack instead of using propriatary batteries

(dg) wrote in message . com...
Faced with a number of battery operated portable items I wondered if
it was possible to make a battery pack that would plug into the units'
mains adapter socket, to power the item.

I presume that mains adapters just output the necessary voltage and
current to power the unit, so If I made up a pack consisting of a
number of 1.2v NiCads to acheive the correct output voltage and use
and a standard connector, then this could power the unit?

Is it this simple or would I need some electronics to regulate to
output voltage?

If its not just a case of batteries, box and a connecting lead, any
pointers to suppliers of the necessary kit would be appreciated.

dg

Thanks for all the replies.

I used to have a battery belt for a video camera ( from the days when
they used to be power hungry!), and I was thinking that something
similar would be useful for some of the devices I carry around today.

Something like a few high capacity D cells may be more portable than a
bigger square pack.

An extended runtime 7.4v battery for a TabletPC I have to use for
extended site visits is nearly £100, so I thought why can't I just use
a pack of normal batteries - not quite as glamorous but probably would
keep me going all day.

That got me thinking about the other devices and equipment etc I have
to frequently carry and recharge.

One query regarding amperage - if I did make up a battery pack to
replace the mains adapter, is it the appliance that draws the current
or is it the pack that supplies the current?
ie if the pack supplied say 'x' volts at 5000ma, but the appliance
stated that it used 'x' volts at 4000ma, would this cause a problem or
just mean it would run for longer?

Sorry if thats a bit OT DIY.

dg