-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Robert L. Nuckolls, III
Sent: Tuesday, January 08, 2013 10:01 AM
To: [email protected]
Subject: AeroElectric-List: Lithium batteries redux

--> AeroElectric-List message posted by: "Robert L. Nuckolls, III"
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This morning's news included a bit concerning a battery fire in a B787 on the ramp at Boston airport.

http://tinyurl.com/bx3ww23

According to Skip Koss (and unlike the
Cessna ramp fire in the Citation) this fire appears to have been controlled by individuals both trained and equipped for dealing with a lithium fire.

A123 (manufacturer of the cells in the Cessna
battery) is shut down in bankruptcy although I understand they've been purchased by a Chinese interest.

Folks. I think it's pretty clear that the large energy storage lithium products are not ready for prime time on airplanes. There's a lot of ground based history being made and new product development being conducted which may ultimately evolve into products with aviation-grade failure modes and risks . . .
let us wait and see.

Sometimes, the best way to drive a nail is with a hammer and the best way to carry a reserve of electrons is with lead-acid.

http://tinyurl.com/3atma44




Bob . . .

Battson wrote:He seems to draw a conclusion without any meaningful evidence to support it? I fear he's on the bandwagon enjoying the ride Mike.....

Battson wrote:Are you able to re-post any of the technical content behind his conclusion?

nuckolls.bob(at)aeroelect
Guest

PostPosted: Tue May 29, 2012 9:28 am Post subject: Lithium aircraft batteries Reply with quote
At 11:15 AM 5/29/2012, you wrote:
Quote:
This technology is outside my field, so I am appealing to others for insight:

‘aircraft battery’ from: wicks aircraft
Underlying technology: a123 systems

There are a lot of hand-waving claims on these batteries, but not a lot of hard technical data. I’m sure that they can be adapted for flight, but some thoughtful ground testing would be useful. Thoughts?

Vern

Li-Ion batteries for have been the Holy Grail
for the TC aviation battery guys for quite some time.
HBC was up to their eyeballs in studies for weight
reduction without sacrificing performance before I
left. I spent a significant amount of time studying
battery issues for HBC in both the legacy (lead-acid)
and shining-star-on-the-horizon worlds.

To Cessna's credit, they spent a barrel of money
and a lot of person-hours getting a Li-Ion product
qualified for their aircraft. In fact, I think it was
a brand new Citation being prepared for a big show
that was fitted with a Li-Ion that caught fire on
the ramp. This experience highlighted a few of
the snakes not yet stuffed into the sack . . .

Nobody had the slightest notion how to fight a lithium
fire . . . nor were they provided the equipment
to do it.

Rumor has it that the battery was being charged on
ground power and some hitch in the systems management
software intended to prevent this accident wasn't
minding the store. This is a RUMOR . . . I'm not yet
privy to inside information of reliable source.

Nonetheless, the incident sparked a rapid recall of
all Li-Ion batteries still in the States. Since
two airplanes were out of the country, Cessna's
prophylactic against another occurrence called for an
A/D to remove the Li-Ion battery in favor of
SVLA or NiCad.

I was asked to evaluate a Li-Ion product for suitability
as a cranking battery on a TC light plane. The inquiry
arrived just weeks before the Cessna ramp incident.
Shucks, if Cessna could do it, I was inclined to
favor use of this particular technology (Li-Fe)
in the putt-putt.

Yes, thousands of these batteries are in service
everywhere and the owners of these batteries swear
by their virtues. Nothing like consumer enthusiasm
to drive up numbers of folks willing to wade in.

It's a simple caveat emptor situation. If the weight
of demonstrated successes combined with the weight
savings is sufficiently powerful to encourage your
own experiment, the risks are not scarry. . . but
probably 1000x greater than for hazards demonstrated
by SVLA devices (read this to mean that SVLA batteries
are exceedingly low hazard).

The other question to be asked and answered, "Okay,
I've saved x.x pounds'. Now how do I use them?"
I'm sure there are times when I left the ground
a few pounds over-gross . . . not sure I'd spend
extra dollars to stay under-gross no matter how safe
the battery might be.

A single weight-savings effort almost never offers
a good return on investment. A TOTAL weight savings
effort produces an airplane like Voyager that was
sucked dry of no-value-added weight. It took
5 pounds of fuel to carry 1 pound of airplane
around the world. 1 pound of empty weight was 6
pounds added weight at takeoff and perhaps 100
miles less range. This thought process produced
an airplane that Dick Rutan feared. He wrote of
nightmares about this airplane killing him.

Someplace between goals and risk assumption
for around-the-world-flight . . . and taking off
for a nice weekend with the wife in Santa Fe, there
is a very comfortable middle ground that probably
is not improved by swapping out the plastic box
of lead for a box of lithium.


Bob . . .

[b]

Karmutzen wrote: ...but please hold off on the fear-mongering fables as the only reason for not moving ahead.

mtv wrote:........I wouldn't bother removing the battery box in a 170 to install one of these unless the battery box was badly corroded. Mine wasn't. If it had been, I'd just buy one of Atlee's brackets, remove the corroded battery box and install the bracket in the same location.......

blackrock wrote:To that end, this is a link to Avweb with some additional discussion about Li-ion batteries. Bye the way, while rare, Li-ion batteries in laptops, cell phones, and other devices continue to catch fire. Simply google lithium ion fires.