Lithium technology batteries

Tim Ward wrote:


Yikes!

I don't see any other advantages for gliders over the standard
sealed lead/acid batteries, which are cheap and trouble free.



Well, Li chemistry batteries have much better performance when it's
cold than either lead, NiCd or NiMH. So that might be a consideration
for those flying wave a lot.

I wondered about that, but didn't happen across any temperature specs.
Do you have a link to one for these types of batteries?

This pilot's performance when he's cold tends to drop off faster than
his battery's performance, unfortunately! Maybe Li batteries would be a
better way to supply power to heated socks and gloves than the usual
alkaline or NiCd.


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Eric Greenwell
Washington State
USA

"Tim Ward" wrote in message
nk.net...

"Eric Greenwell" wrote in message
...
Ken Kochanski (KK) wrote:

Although the technology is still pricy vs lead-acid batteries, the
power/weight/size vs cost equation is getting better. Anybody using
lithium model airplane packs bundeled to produce 12 - 14 v @3 - 6
amps
as a power source for their glider? (I have been looking at the
duralite site ... I'm sure there are others.)
http://www.duralitebatteries.com/batteries.html

The recommended
safe charging procedure for all Li-ion & Li-Poly
batteries is to charge them out of the aircraft in a ?re
proof area or container. Always be present during the
charging cycle. Unplug the batteries from charger when
charging cycle is complete.


I think this applies only to the first generation electric powered model
airplane batteries. There are tens of millions of lithium ion and lithium
polymer cellphone batteries charged on nightstands with few problems. Where
there were problems it has turned out to be counterfeit made in China
aftermarket batteries. Even the second generation model airplane batteries
have pretty well put the fire problem behind them.

Why Li-Po? Well one reason is that their light weight allows them to be
placed just behind the instrument panel where very short power leads lose
less power. Heavy SLA's usually have to go behind the seat and use long
wires to the panel.

Bill Daniels

I looked at these guys earlier this year. Unfortuneately, they did not have
an "off the shelf" solution. Lithium without the fire hazard....

http://www.valence.com

AT


"Ken Kochanski (KK)" wrote in message
oups.com...
Although the technology is still pricy vs lead-acid batteries, the
power/weight/size vs cost equation is getting better. Anybody using
lithium model airplane packs bundeled to produce 12 - 14 v @3 - 6 amps
as a power source for their glider? (I have been looking at the
duralite site ... I'm sure there are others.)
http://www.duralitebatteries.com/batteries.html

KiloKilo

These retailers are expensive - go to the source
http://sabahoceanic.com/SearchResult.aspx?CategoryID=9
They will tag them for free
Use 8x BR-C and you will get 12V 10000mah for $128
(these are 3v cells as opposed to the normal 3.7v)

Can do it cheaper with some of the other cells

Used them to replace my laptop batts - fast efficient service. Downside is
that chargers & electronics are scarce
rgds
Stephen

"Atacdad" wrote in message
...
I looked at these guys earlier this year. Unfortuneately, they did not
have an "off the shelf" solution. Lithium without the fire hazard....

http://www.valence.com

AT


"Ken Kochanski (KK)" wrote in message
oups.com...
Although the technology is still pricy vs lead-acid batteries, the
power/weight/size vs cost equation is getting better. Anybody using
lithium model airplane packs bundeled to produce 12 - 14 v @3 - 6 amps
as a power source for their glider? (I have been looking at the
duralite site ... I'm sure there are others.)
http://www.duralitebatteries.com/batteries.html

KiloKilo

Stephen Haley wrote:
These retailers are expensive - go to the source
http://sabahoceanic.com/SearchResult.aspx?CategoryID=9
They will tag them for free
Use 8x BR-C and you will get 12V 10000mah for $128
(these are 3v cells as opposed to the normal 3.7v)

These are interesting, but their voltage falls off a lot with current
and temperatu Volts/cell = 2.2 (300 ma drain, 32 F); . That's only
8.8 volts with 4 cells in series, so you'd need at least 5 in series
just to get 11 volts.

But the size and weight are sure attractive (for four cells) compared to
a 12 volt, 5 ah SLA battery: about the same height and length, but less
than half the thickness, and 6 ounces vs 60! No wonder the model
airplane people like them!

There sure is a variation in output currents for similar amphours. This
unit

Saft Lithium LS26500 [C] 3.6V. 7700mAh

is limited to 10 ma!

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Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

What I wish for is a 14V, 12 AH Lithium-Polymer battery pack that comes with
a "snap-in" fixture. It would be nice to just snap in a freshly charged
battery just before a flight instead of fiddling with wires and battery
tie-downs or charging the battery in the glider. Maybe something that goes
in a 57mm instrument hole.

Bill Daniels

"Ken Kochanski (KK)" wrote in message
oups.com...
Although the technology is still pricy vs lead-acid batteries, the
power/weight/size vs cost equation is getting better. Anybody using
lithium model airplane packs bundeled to produce 12 - 14 v @3 - 6 amps
as a power source for their glider? (I have been looking at the
duralite site ... I'm sure there are others.)
http://www.duralitebatteries.com/batteries.html

KiloKilo

Lithium powered electric socks? www.cozywinters.com
williscomb