On Tue, 6 Jan 2004, Markus L wrote:

Thank you for the pointer to the on-line book! I had a good read.

Li-Ion batteries are dangerous, they may explode if (a) overcharged or (b)
discharged too rapidly. That's why individual cells are almost unavailable.
Battery packs come with the necessary circuitry to protect the cells. As
long as you use an existing pack I wouldn't be too concerned. Please note
that contrary to NiCd, Li-Ion cells cannot deliver high peak currents. The
expert at www.buchmann.ca indicates a peak load of 2C for Li-Ion vs 20C for
NiCd.

In this case I'm considering using the laptop battery itself, not opening
it up and extracting the cells. Overcharging shouldn't be a problem,
because I'd be using the laptop itself to recharge the battery. I don't
think that I'll be drawing too much current, either, as the DSW-40 (an
original one) only puts out about 2 watts.

BUT, with the warnings about Li-Ion cells in mind I think I'll see if I
can learn more about the battery packs made for my particular laptop to
determine if I really want to do this.

Thanks!

-Josh, AE6IQ

--


Remove the reversed "nospam" in the address.

In this case I'm considering using the laptop battery itself, not opening
it up and extracting the cells. Overcharging shouldn't be a problem,
because I'd be using the laptop itself to recharge the battery. I don't
think that I'll be drawing too much current, either, as the DSW-40 (an
original one) only puts out about 2 watts.

BUT, with the warnings about Li-Ion cells in mind I think I'll see if I
can learn more about the battery packs made for my particular laptop to
determine if I really want to do this.


At 2 watts, your DSW-40 current requirment is pretty low....way below the
battery's A/H rating. WAY BELOW. I=P/E = 2/12 = 160ma.

If you are that worried about using the laptop battery, get a 12v lantern
battery. It will last for months of QSO's. I used one with an HW-8 and it
was FB for about 3 or 4 months. It lasted so long, I thought it would never
run down. With your DSW-40, it might lose more energy through shelf-life
than operating time. :-)

Either way you go, go for it.

73
dale, kg5u

In this case I'm considering using the laptop battery itself, not opening
it up and extracting the cells. Overcharging shouldn't be a problem,
because I'd be using the laptop itself to recharge the battery. I don't
think that I'll be drawing too much current, either, as the DSW-40 (an
original one) only puts out about 2 watts.

BUT, with the warnings about Li-Ion cells in mind I think I'll see if I
can learn more about the battery packs made for my particular laptop to
determine if I really want to do this.


At 2 watts, your DSW-40 current requirment is pretty low....way below the
battery's A/H rating. WAY BELOW. I=P/E = 2/12 = 160ma.

If you are that worried about using the laptop battery, get a 12v lantern
battery. It will last for months of QSO's. I used one with an HW-8 and it
was FB for about 3 or 4 months. It lasted so long, I thought it would never
run down. With your DSW-40, it might lose more energy through shelf-life
than operating time. :-)

Either way you go, go for it.

73
dale, kg5u