[Elecraft] Still lacking

[Erik Basilier]

Ummm. correct me if I am wrong, but it looks to me as if Leigh is referring
to Lithium Ferro Phosphate batteries (also known as Lithium Iron Phosphate),
while Jack is thinking Lithium Polymer. Not at all the same thing. If I
remember correctly, Lithium Polymer was involved in some published incidents
of batteries in cellphones or laptops catching fire. I believe the Lithium
Ferro Phosphate variety is a lot safer, although not safe under all
conditions. Probably both varieties will last a lot longer if balanced
charging is used, meaning that the charger monitors and charges each cell
individually (at the same time) depending on how empty it is found to be. I
have had a LiFePO4 battery sold by Buddipole for about a year, and I am very
impressed. The charger is a box about 4.3 x 3.6 x 1.0 inches which weighs
about 7.6 oz. It has a 3 ft cable with APP for 12 VDC input power, and a
small multipole connector for output. The battery pack has a short output
cable with APP and a short multipole input cable that plugs into the
charger. The charger is small and light enough to be carried easily into the
field. The battery can provide very high output current for a short time, I
believe enough to power a 100 W transmitter briefly. The charger provides
balanced charging for LiFePO4 batteries but can also handle a wide variety
of other battery types. The smart charger uses 10 to 16 VDC, and the input
voltage doesn't need to exceed the voltage of the battery being charged. 

 

73,

Erik K7TV

 

> Consider that IF you are taking  your station on commercial aircraft, in
some countries the carriage of LiPo batteries is very restricted,
particularly if the pack is not enclosed within the device they power. 

> I carry a VRSLA battery that is approved and so marked to meet the 

> IATA A67 standard, Qantas in Australia also require an application for 

> permit to carry the above battery, along with the relevant MSDS, permit is
good for 3 months travel in the passengers name.  The battery and permit,
with MSDS must be declared at checkin.

> I did not want to even think about trying to get approval for a LiPo 

> battery pack, the VRSLA one was bad enough :-)

> 

> 

> 73,

> 

> Jack. VK4JRC

> 

> Sent from my iPad

> 

> On 02/06/2011, at 9:53 AM, "Leigh L. Klotz Jr WA5ZNU" <Leigh at WA5ZNU.org>
wrote:

> 

>> I'd suggest LiFePO4 batteries, as they can source the current 

>> necessary for the transmitter easily, and are safer in operation than
Lithium Polymer.

>> They can be safely charged on a portable solar panel if you 

>> disconnect once the voltage reaches 14.4v, and that's pretty much 

>> what the SLA charge controllers do as well.  The 2.4 AH packs charge 

>> at about 1.5 Amps, so it's hard to bring too big a panel!

>> 

>> Leigh/WA5ZNU