[TenTec] OT: Anyone used LiFePo technology yet for portable operations?

[Rick - DJ0IP / NJ0IP]

Hi Jim,

Very interesting indeed.
Last question first.
I intend to climb as little as possible.
I will use a motorbike to get as high as possible and only hike the last wee
little bit.

I posted the same question to the BCC yesterday and two guys (SOTA guys)
answered.
One has a 5 Ah battery and 5w QRP rig.  He says he is on the air for 5 hrs
with that and has power to spare.  

The battery I'm looking at is 12 Ah so I suppose my Scout can run @ 50w for
that many hours.
Before I spend the money, though, I'm going to pack a backpack with some
rocks and try a small mountain.  We'll see how enthused I am afterwards.

When all else fails, I have two mountains near here where I can ride a
motorbike to the top and one even has a castle on it, so it counts as COTA
too.  If I fail the dress rehearsal (with the rocks), that may be the route
I go.  In any case, I'm getting out of the house and away from this dang
keyboard this summer!

Tnx agn.

73 - Rick, DJ0IP
(Nr. Frankfurt am Main)


-----Original Message-----
From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of Jim Brown
Sent: Monday, April 27, 2015 7:32 PM
To: tentec at contesting.com
Subject: Re: [TenTec] OT: Anyone used LiFePo technology yet for portable
operations?

On Mon,4/27/2015 1:33 AM, Rick - DJ0IP / NJ0IP wrote:
> So the question, has anyone actually used the LiFePo for portable 
> operations with success?

Your question is timely, Rick. As it happens, my friend Scott, AF6RT, is
preparing for a backpacking effort to activate CM79 on 6M for those pursuing
the Fred Fish award (working all grids within the lower 48 US states on 6M).
It's a difficult hike, up 800 ft in the first 0.8 miles, then another mile
or so along the ridge to a point within the grid. Most of the grid is water
-- only a half mile by half mile is on land. He's done this several times
before.

My neighbor, W6GJB, and I are contributing to the effort by buying
LiFePO4 batteries that we're loaning to Scott, and I've loaned him my
KX3 and KXPA100 amp, which, because it's designed as a backpacking radio,
has the virtues of very low current drain on receive, light weight, and a
built-in preamp good enough that an outboard preamp is not needed.

Glen, W6GJB, is an engineer recently retired from the space program, and
both he and I have thoroughly investigated Li battery technology as it might
apply to ham radio. We have both come to the conclusion that
LiFePO4 chemistry is the best solution for TODAY -- its terminal voltage is
in the optimum range for our ham gear, it has a very good discharge curve
(rather flat), it does not have the "easy to catch on fire or explode"
issues of Li Ion, and it is more tolerant of charging.

The battery I bought is rated 20Ah at 12V with a maximum discharge rate of
40A. Like any battery, the Ah rating is for a far more moderate discharge
rate. :) It weighs 5 pounds, 9 ounces (on my XYL's precision scale).

http://www.bioennopower.com/collections/12v-series-lifepo4-batteries/product
s/12v-20ah-lfp-battery-black-pvc-pack

It is part number BLF-1220W. It comes with Power Pole connector to go to the
load, and a concentric connector for charging. I paid $213 plus tax and
shipping, which came to about $250.

The battery that Glen bought (several months before I bought mine) weighs 7
pounds 5 ounces, is also rated 20 Ah at 12V, and uses LiFePO4 chemistry. It
comes in a somewhat larger package. He bought it here.  
http://www.batteryspace.com/

Both of these companies have intelligent people responding to emails and
talking on the telephone. Their prices seem competitive and comparable to
each other. The reason for the wide diversity of part numbers and packages
is so that they can replace OEM batteries in existing products
-- everything from CPAP machines to model airplanes.

It's my understanding that this battery chemistry has been adopted by the
SOTA (summits on the air) crowd.

> I just wonder if it's really worth the extra money going with this new 
> technology, or should I buy a cheap GEL for now and come back to 
> LiFePo in 3 or 4 years when it is cheaper?

The reason for choosing any of the Li chemistries is WEIGHT. How many
mountains do you intend to climb in those 3-4 years?

73, Jim K9YC
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