a Li-Ion in a lead acid world.

[brianDG303[_2_]]

I’ve been experimenting around with Li-Ion batteries for a few months
now, just for fun, and thought I would pass on a few observations that
might be interesting. I only experimented with Li-Ions that had a
separate printed circuit board incorporated into each cell, and I was
not able to ignite these by any combination of overload, short
circuit, or charging abnormality. At low levels of abuse including
dead shorting, the battery would just shut down, but at some point the
PCB would fail and that was the end of the battery. I was able to get
a very impressive fire with a lot of smoke by blunt force trauma with
the conclusion that in the event of a Li-Ion fire the only survivable
option would be to jettison the canopy, and then maybe jump. But I
ended up deciding that the odds of a fire were quite low.

I flew most of the season with a 3.6 AH (measured, not claimed)
battery running either the transponder, the radio, or the PNA and one
issue that came up was that some electronics do not like voltage of
less than 10.8 volts and the Li-Ion discharge curve (which was 11.8 to
9 volts) is such that they may have viable amperage right down to 9
volts that becomes useless. The radio (Becker) went into survival
mode at low voltages while the PNA, running from a 12 volt car
adapter, was happy

Rather late in the game I discovered that there has been a development
in the battery world I hadn’t heard about- more capacity in the same
size Lead Acid battery case. My glider came with a UB12100, a 7.5 lb
10 amp hour battery. I was able to swap it up to a UB12120, an 8.5 lb
12 amp hour battery, same size. Now I am able to find the UB12150
battery, again a direct replacement for a very common sailplane
battery size, now approaching 10 lbs but with a capacity of 15 AH.

My end result is to trade up to the new 15 AH battery and rig the 3.6
AH Li-Ion as a reserve. I seem to pull about .8 amps now running
everything off the main battery, but there are back-up batteries in
the Vario and the PNA I can switch to, so the plan would be, in the
event of a low main battery, to switch to all the back-up batteries
and employ a conservation strategy.

The Li-Ion battery I ended up with is here:

http://www.dinodirect.com/Super-9000mA-Rechargeable-Li-ion-Battery-for-Security-CCTV-Camera-YSD-12900.html

You can just ignore the claimed 9000 mA rating. At .8 amp draw I get
just 3.6 Ah to shut down.

Hope it was worth the read,

Brian

[SoaringXCellence]

Brian,

Thanks for the detailed report. I very glad someone is trying this
kind of thing out in a safe environment and sharing the results with
the rest of us.

Mike

[JS]

Thanks for testing and posting that, Brian. Well worth the read.
There's been much speculation about Li-Ions. The max voltage / power
curve bit is always a problem.
It will be interesting to see how the Universal batteries age. So many
batteries that we knew and loved seem now a shadow of their former
selves quality wise.
Are Sonnenschein batteries the best way to go? Tom Knauff stocks a
couple of sizes, but not all. Many web searches come up with
substitute batteries of lower quality.
Jim

[Darryl Ramm]

On Nov 11, 10:14*pm, JS > wrote:
[snip]
> * Are Sonnenschein batteries the best way to go? Tom Knauff stocks a
> couple of sizes, but not all. Many web searches come up with
> substitute batteries of lower quality.
> Jim

being a battery geek I'll bite...

Unlikely - Sonnenschein are Gel cells (electrolyte in fused silica)
and Gel really just do not offer significant advantage over VRLA. If
they did there would not have been an almost total move in the sealed
lead acid battery market from Gel Cell to VRLA technology. Go for a
good quality brand name VRLA (Valve Regulated Lead Acid, aka starved
electrolyte lead acid battery, aka recombinant gas valve regulated
lead acid battery). Panasonic, PowerSonic, etc. Most are made in China
but the brand name still matters. Buy from a distributor with good
turnover, charge with a battery charger specifically designed for VRLA
batteries, don't charge at high temps, and select a charger with a
bulk charge specs to ~ C/10 to C/5, disconnect from the charger when
complete (unless you really know and trust the charger has a proper
float mode), charge as soon as possible after use - don't leave flat
for long periods of time, discharge test once a year and write the
test date and capacity on the battery and toss when capacity starts to
fall significantly. VRLA are very low cost and very effective for what
they do.

Disadvantages of gel cells are higher cost for no real benefit, maybe
prone to damage from high charge currents (formation of voids in the
gel) - but VRLA are prone to evaporate off electrolyte from
overcharging. And a general benefit of VRLA is the broad industry
investment in VRLA technology.

Unfortunately many people call any sealed lead acid battery a "gel
cell" not realizing almost all are VRLA.

Darryl

[Darryl Ramm]

On Nov 11, 10:38*pm, Darryl Ramm > wrote:
> On Nov 11, 10:14*pm, JS > wrote:
> [snip]
>
> > * Are Sonnenschein batteries the best way to go? Tom Knauff stocks a
> > couple of sizes, but not all. Many web searches come up with
> > substitute batteries of lower quality.
> > Jim
>
> being a battery geek I'll bite...
>
> Unlikely - Sonnenschein are Gel cells (electrolyte in fused silica)
> and Gel really just do not offer significant advantage over VRLA. If
> they did there would not have been an almost total move in the sealed
> lead acid battery market from Gel Cell to VRLA technology. Go for a
> good quality brand name VRLA (Valve Regulated Lead Acid, aka starved
> electrolyte lead acid battery, aka recombinant gas valve regulated
> lead acid battery). Panasonic, PowerSonic, etc. Most are made in China
> but the brand name still matters. Buy from a distributor with good
> turnover, charge with a battery charger specifically designed for VRLA
> batteries, don't charge at high temps, and select a charger with a
> bulk charge specs to ~ C/10 to C/5, disconnect from the charger when
> complete (unless you really know and trust the charger has a proper
> float mode), charge as soon as possible after use - don't leave flat
> for long periods of time, discharge test once a year and write the
> test date and capacity on the battery and toss when capacity starts to
> fall significantly. VRLA are very low cost and very effective for what
> they do.
>
> Disadvantages of gel cells are higher cost for no real benefit, maybe
> prone to damage from high charge currents (formation of voids in the
> gel) - but VRLA are prone to evaporate off electrolyte from
> overcharging. And a general benefit of VRLA is the broad industry
> investment in VRLA technology.
>
> Unfortunately many people call any sealed lead acid battery a "gel
> cell" not realizing almost all are VRLA.
>
> Darryl

Grrr !@# automatic spell checker. Gel cells have electrolyte in "fumed
silica" not "fused silica". To see what this means see
http://en.wikipedia.org/wiki/Fumed_silica.

BTW VRLA batteries have electrolyte suspended in fiberglass mats
packed tightly between the plates. They are barely damp hence the
"starved electrolyte" terminology. The tight packing between these
mats makes the batteries very robust. Because the plates no longer
have to be as rigid/robust by themselves as in an old style flooded
lead acid battery the plates can be purer lead and don't need alloying
for strength/rigidity. That results in chemistry that give much lower
self discharge rates (why you do *not* need to leave a VRLA battery on
a charger over winter etc.) and better internal resistance properties
compared to flooded lead acid batteries. There is a slight
overpressure on the battery managed by neoprene vents and a close
cycle chemical reaction where gasses are recombined with help from a
catalyst. Hence the "recombinant gas" terminology sometimes used.

Gel cells share some of these features as well but its been exploited
more in VRLA designs.


Darryl

[guy]

kBrian,
You gave us the model number of thebattery (UB12150) but not the
brand.
Guy

[brianDG303[_2_]]

On Nov 12, 4:54*am, guy > wrote:
> kBrian,
> You gave us the model number of thebattery (UB12150) but not the
> brand.
> Guy

There are two big battery houses I use (Seattle), one is a giant
Interstate Battery warehouse. Either one, they sell me a generic black
brick- Universal Battery ( by Universal Power group). I've had great
luck with them and you see them everywhere.

http://www.powerstridebattery.com/alarm-batteries/12-volt-15-ah-sla-battery-ub12150

or with lots of spec's

http://www.batteryplex.com/sheets/EVH12150.pdf

or

http://www.batteryplex.com/universal.cfm/m/UB12150-F2

or ebay even. $40 delivered to your door, about $30 if you drive
across town. I like to drive, so I can read the date code stamped on
the battery, but I bet the mail-order guys go through them pretty
fast.

Brian

[Frank[_12_]]

On Nov 12, 12:14*am, brianDG303 > wrote:
> I’ve been experimenting around with Li-Ion batteries for a few months
> now, just for fun, and thought I would pass on a few observations that
> might be interesting. *I only experimented with Li-Ions that had a
> separate printed circuit board incorporated into each cell, and I was
> not able to ignite these by any combination of overload, short
> circuit, or charging abnormality. At low levels of abuse including
> dead shorting, the battery would just shut down, but at some point the
> PCB would fail and that was the end of the battery. *I was able to get
> a very impressive fire with a lot of smoke by blunt force trauma with
> the conclusion that in the event of a Li-Ion fire the only survivable
> option would be to jettison the canopy, and then maybe jump. But I
> ended up deciding that the odds of a fire were quite low.
>
> I flew most of the season with a *3.6 AH (measured, not claimed)
> battery running either the transponder, the radio, or the PNA and one
> issue that came up was that some electronics do not like voltage of
> less than 10.8 volts and the Li-Ion discharge curve (which was 11.8 to
> 9 volts) is such that they may have viable amperage right down to 9
> volts that becomes useless. *The radio (Becker) went into survival
> mode at low voltages while the PNA, running from a 12 volt car
> adapter, was happy
>
> Rather late in the game I discovered that there has been a development
> in the battery world I hadn’t heard about- more capacity in the same
> size Lead Acid battery case. My glider came with a UB12100, a 7.5 lb
> 10 amp hour battery. I was able to swap it up to a UB12120, an 8.5 lb
> 12 amp hour battery, same size. Now I am able to find the UB12150
> battery, again a direct replacement for a very common sailplane
> battery size, now approaching 10 lbs but with a capacity of 15 AH.
>
> My end result is to trade up to the new 15 AH battery and rig the 3.6
> AH Li-Ion as a reserve. I seem to pull about .8 amps now running
> everything off the main battery, but there are back-up batteries in
> the Vario and the PNA I can switch to, so the plan would be, in the
> event of a low main battery, to switch to all the back-up batteries
> and employ a conservation strategy.
>
> The Li-Ion battery I ended up with is here:
>
> http://www.dinodirect.com/Super-9000mA-Rechargeable-Li-ion-Battery-fo...
>
> You can just ignore the claimed 9000 mA rating. At .8 amp draw I get
> just 3.6 Ah to shut down.
>
> Hope it was worth the read,
>
> Brian

Take a look at Scott Fletcher's article in this month's Soaring
Magazine. While very expensive (about 5x), the Li-Fe-Po (Lithium-Iron-
Phosphate) battery pack is a lot better suited to soaring use than
either Li-ion or SLA batteries. The K2 Energy (http://
www.peakbattery.com/) 12V 10AH pack is the same size and form factor
as my regular UB1290 (12v 9.0AH SLA), and is considerably lighter. It
is also (according to the company and some independent research) a lot
safer in that it won't explode or catch fire when abused. Lastly, its
discharge curve runs between 13.2V fully charged to about 12.5V at end-
of-charge, making it a better fit for most avionics.

I bought one for my Ventus 2 because I am planning to install a
transponder this winter and a FLARM unit next spring, so will need
some additional amp-hours. I plan to run with one SLA and one LiFePo
next year, and then get another K2 battery after the end of next
season.

Frank (TA)

[Herbert kilian]

On Nov 12, 9:00*am, Frank > wrote:
> On Nov 12, 12:14*am, brianDG303 > wrote:
>
>
>
> > I’ve been experimenting around with Li-Ion batteries for a few months
> > now, just for fun, and thought I would pass on a few observations that
> > might be interesting. *I only experimented with Li-Ions that had a
> > separate printed circuit board incorporated into each cell, and I was
> > not able to ignite these by any combination of overload, short
> > circuit, or charging abnormality. At low levels of abuse including
> > dead shorting, the battery would just shut down, but at some point the
> > PCB would fail and that was the end of the battery. *I was able to get
> > a very impressive fire with a lot of smoke by blunt force trauma with
> > the conclusion that in the event of a Li-Ion fire the only survivable
> > option would be to jettison the canopy, and then maybe jump. But I
> > ended up deciding that the odds of a fire were quite low.
>
> > I flew most of the season with a *3.6 AH (measured, not claimed)
> > battery running either the transponder, the radio, or the PNA and one
> > issue that came up was that some electronics do not like voltage of
> > less than 10.8 volts and the Li-Ion discharge curve (which was 11.8 to
> > 9 volts) is such that they may have viable amperage right down to 9
> > volts that becomes useless. *The radio (Becker) went into survival
> > mode at low voltages while the PNA, running from a 12 volt car
> > adapter, was happy
>
> > Rather late in the game I discovered that there has been a development
> > in the battery world I hadn’t heard about- more capacity in the same
> > size Lead Acid battery case. My glider came with a UB12100, a 7.5 lb
> > 10 amp hour battery. I was able to swap it up to a UB12120, an 8.5 lb
> > 12 amp hour battery, same size. Now I am able to find the UB12150
> > battery, again a direct replacement for a very common sailplane
> > battery size, now approaching 10 lbs but with a capacity of 15 AH.
>
> > My end result is to trade up to the new 15 AH battery and rig the 3.6
> > AH Li-Ion as a reserve. I seem to pull about .8 amps now running
> > everything off the main battery, but there are back-up batteries in
> > the Vario and the PNA I can switch to, so the plan would be, in the
> > event of a low main battery, to switch to all the back-up batteries
> > and employ a conservation strategy.
>
> > The Li-Ion battery I ended up with is here:
>
> >http://www.dinodirect.com/Super-9000mA-Rechargeable-Li-ion-Battery-fo...
>
> > You can just ignore the claimed 9000 mA rating. At .8 amp draw I get
> > just 3.6 Ah to shut down.
>
> > Hope it was worth the read,
>
> > Brian
>
> Take a look at Scott Fletcher's article in this month's Soaring
> Magazine. *While very expensive (about 5x), the Li-Fe-Po (Lithium-Iron-
> Phosphate) battery pack is a lot better suited to soaring use than
> either Li-ion or SLA batteries. *The K2 Energy (http://www.peakbattery.com/) 12V 10AH pack is the same size and form factor
> as my regular UB1290 (12v 9.0AH SLA), and is considerably lighter. *It
> is also (according to the company and some independent research) a lot
> safer in that it won't explode or catch fire when abused. *Lastly, its
> discharge curve runs between 13.2V fully charged to about 12.5V at end-
> of-charge, making it a better fit for most avionics.
>
> I bought one for my Ventus 2 because I am planning to install a
> transponder this winter and a FLARM unit next spring, so will need
> some additional amp-hours. *I plan to run with one SLA and one LiFePo
> next year, and then get another K2 battery after the end of next
> season.
>
> Frank (TA)

Frank is right the Li-Fe batteries are ideal for us, a 4-cell has
discharge voltages very close to our regular 6-cell Lead-Acid
batteries. Unfortunately, the Li-Fe cells are quite expensive, much
higher than any of the other technologies. Discharge voltage curve is
very flat, better than anything else I've seen.
Another technology that is mature and low price are Ni-Mh batteries.
They don't have the memory problems of Ni-Cads and can be recharged at
fairly high currents. I've flown for over 5 years now with two 6AH
packs for instrumentation (one is the spare, located in the tail) and
one 10AH pack dedicated to the transponder. These slightly discharge
over time (10% per month or so) but since I put them on the charger
the night before flying that has not been an issue. Weight is about
2/3 of a similar Lead-Acid battery.
Herb, J7

[sisu1a]

> The Li-Ion battery I ended up with is here:
> http://www.dinodirect.com/Super-9000mA-Rechargeable-Li-ion-Battery-fo...
> Hope it was worth the read,


Other than price, is there a compelling reason to use Li-Ion batteries
instead of LiFeP04 batteries like these?
http://www.batteryspace.com/128vlifepo4batterypacks.aspx I know some
folks using batteries/chargers from these guys are are quite happy
with them... many options at many pricepoints...

-Paul

[brianDG303[_2_]]

Hi Frank,
I looked twice at the Peak Battery site but could never find any
dimensions. Can you provide the dimensions or a link to that part of
the site?

When you say that the Peak battery is a lot safer, I'm not all that
convinced, because 1) I was never able to ignite the Li-Ion's other
than with a hammer, and 2) everyone is flying with Li-Ions, in cell
phones, iPaq's, Oudies, Socket Mobile power packs, etc. and I don't
hear of those catching on fire, ever. Not to mention all the Li-Ion's
sitting on job sites everywhere all night on chargers, if one burned
in Seattle I would know about it.
But I think that is something for each person to decide and I won't
attempt to convince anyone Li-Ion's are safe, just to consider how
many they are already flying with. One of the batteries I burned up
was from an Ipaq 3950 and it was clear that you Can Not survive such
an event without losing the canopy at a minimum. The smoke, not only
from the battery but from the plastic case and components goes on for
about 90 seconds, is very acrid, think burning tires. The youtube
videos don't do it justice, I think because they burn the battery only
and not a PDA/PNA at the same time which is where a lot of the smoke
comes from.

That being said, I would not go to an all Peak Battery solution
myself, too much expense. But the $140, 7ah version might be an option
for a back-up to a UB12150 VRLA ($40). I wonder what life you would
get out of the Peak Battery if you used it only 6 times per year?

Brian


> Take a look at Scott Fletcher's article in this month's Soaring
> Magazine. *While very expensive (about 5x), the Li-Fe-Po (Lithium-Iron-
> Phosphate) battery pack is a lot better suited to soaring use than
> either Li-ion or SLA batteries. *The K2 Energy (http://www.peakbattery.com/) 12V 10AH pack is the same size and form factor
> as my regular UB1290 (12v 9.0AH SLA), and is considerably lighter. *It
> is also (according to the company and some independent research) a lot
> safer in that it won't explode or catch fire when abused. *Lastly, its
> discharge curve runs between 13.2V fully charged to about 12.5V at end-
> of-charge, making it a better fit for most avionics.
>
> I bought one for my Ventus 2 because I am planning to install a
> transponder this winter and a FLARM unit next spring, so will need
> some additional amp-hours. *I plan to run with one SLA and one LiFePo
> next year, and then get another K2 battery after the end of next
> season.
>
> Frank (TA)

[brianDG303[_2_]]

On Nov 12, 8:33*am, sisu1a > wrote:
> *> The Li-Ion battery I ended up with is here:
>
> >http://www.dinodirect.com/Super-9000mA-Rechargeable-Li-ion-Battery-fo...
> > Hope it was worth the read,
>
> Other than price, is there a compelling reason to use Li-Ion batteries
> instead of LiFeP04 batteries like these?http://www.batteryspace.com/128vlifepo4batterypacks.aspx*I know some
> folks using batteries/chargers from these guys are are quite happy
> with them... many options at many pricepoints...
>
> -Paul

Paul,
those look really nice.

Brian

[brianDG303[_2_]]

Frank, I have a problem with those Peak Batteries, the web site
doesn't give enough information. Size, what kind of charger, etc.
Maybe you or someone could dig into it a little and report back. I did
read the article in Soaring but felt it was thin in places.

Brian


>
> Take a look at Scott Fletcher's article in this month's Soaring
> Magazine. *While very expensive (about 5x), the Li-Fe-Po (Lithium-Iron-
> Phosphate) battery pack is a lot better suited to soaring use than
> either Li-ion or SLA batteries. *The K2 Energy (http://www.peakbattery.com/) 12V 10AH pack is the same size and form factor

>
> Frank (TA)

[jcarlyle]

Brian,

Very interesting post! I've never given a thought to the fact my cell
phone and iPAQ batteries were Li-ion.

You mention that you ignited a Li-ion with a hammer. That's not very
realistic as an in-cockpit trigger, so in your view what might cause a
Li-ion battery in a cell phone or a iPAQ (that had been fully charged
on the ground) to catch fire?

-John

On Nov 12, 2:45 pm, brianDG303 > wrote:
> When you say that the Peak battery is a lot safer, I'm not all that
> convinced, because 1) I was never able to ignite the Li-Ion's other
> than with a hammer, and 2) everyone is flying with Li-Ions, in cell
> phones, iPaq's, Oudies, Socket Mobile power packs, etc. and I don't
> hear of those catching on fire, ever. Not to mention all the Li-Ion's
> sitting on job sites everywhere all night on chargers, if one burned
> in Seattle I would know about it.
> But I think that is something for each person to decide and I won't
> attempt to convince anyone Li-Ion's are safe, just to consider how
> many they are already flying with. One of the batteries I burned up
> was from an Ipaq 3950 and it was clear that you Can Not survive such
> an event without losing the canopy at a minimum. The smoke, not only
> from the battery but from the plastic case and components goes on for
> about 90 seconds, is very acrid, think burning tires. The youtube
> videos don't do it justice, I think because they burn the battery only
> and not a PDA/PNA at the same time which is where a lot of the smoke
> comes from.

[Dave Nadler]

On Nov 12, 12:14*am, brianDG303 > wrote:
> ... I was
> not able to ignite these by any combination of overload,
> short circuit, or charging abnormality.

Clearly an amateur ;-)

[sisu1a]

> > ... I was
> > not able to ignite these by any combination of overload,
> > short circuit, or charging abnormality.
>
> Clearly an amateur ;-)

I think we should pitch in and buy him this shirt:
http://lib.store.yahoo.net/lib/yhst-11870311283124/tried-asphalt.gif

Note- the SunSeeker (http://solar-flight.com/sunseeker/index.html) has
a 'battery ejection' system in case of ignition of it's LIon
batteries. It's a fancy sting and pulley thing if memory serves, but
should release it's incendiary payload in a pinch -hopefully before
the rest of the plastic goes all flaming marshmellow...(look out
below!)

-Paul

ps. did you try the exacto trick? (stab deeply w/#11 blade and quickly
jump out of way of ensuing focused plasma flame ;)

[Frank[_12_]]

On Nov 12, 2:54*pm, brianDG303 > wrote:
> Frank, I have a problem with those Peak Batteries, the web site
> doesn't give enough information. Size, what kind of charger, etc.
> Maybe you or someone could dig into it a little and report back. I did
> read the article in Soaring but felt it was thin in places.
>
> Brian
>
>
>
>
>
>
>
>
>
> > Take a look at Scott Fletcher's article in this month's Soaring
> > Magazine. *While very expensive (about 5x), the Li-Fe-Po (Lithium-Iron-
> > Phosphate) battery pack is a lot better suited to soaring use than
> > either Li-ion or SLA batteries. *The K2 Energy (http://www.peakbattery.com/) 12V 10AH pack is the same size and form factor
>
> > Frank (TA)

Brian,

The K2 site sells a compatible charger (which btw is also much smaller/
lighter than my older VDC Electronics Battery Minder Plus), and will
charge two K2 LiFePo batteries in parallel. Cost for one battery, one
charger and shipping to Columbus OH was about $242 US.

The combination is much more expensive than my SLA setup. However,
when I consider the cost of modifying my battery compartments to
accommodate larger batteries, or the potential cost (i.e., my life!)
of not having a transponder/FLARM next year, I'm comfortable with the
tradeoff ;-).

Frank (TA)

[Mike the Strike]

I remember fun days working in a lab where colleagues were developing
the "revolutionary" sodium sulfur battery (colloquially referred to as
the "fire and brimstone" battery). The chief skill developers learned
was how to run fast while wearing asbestos suits and full-face
protective helmets. If you've never had to deal with a bucket of
burning molten sodium, you've never lived! (Hint - water isn't
terribly useful!) You probably wouldn't want any quantity of burning
(molten or otherwise) lithium near you or in your glider either.

Lithium is WAY too close to the reactive end of the periodic table
(right up there with sodium, magnesium and potassium).

MIke

[[email protected]]

> Lithium is WAY too close to the reactive end of the periodic table
> (right up there with sodium, magnesium and potassium).
>
> MIke

Most smaller Cessnas and the Grob G-103 have magnesium wheels....and I
like bananas for the potassium before I fly.

;-)

aerodyne

[Darryl Ramm]

On Nov 13, 7:54*am, wrote:
> > Lithium is WAY too close to the reactive end of the periodic table
> > (right up there with sodium, magnesium and potassium).
>
> > MIke
>
> Most smaller Cessnas and the Grob G-103 have magnesium wheels....and I
> like bananas for the potassium before I fly.
>
> ;-)
>
> aerodyne

Mmmmm radioactive bananas.

Darryl

[brianDG303[_2_]]

On Nov 12, 9:29*pm, Mike the Strike > wrote:
> I remember fun days working in a lab where colleagues were developing
> the "revolutionary" sodium sulfur battery (colloquially referred to as
> the "fire and brimstone" battery). *The chief skill developers learned
> was how to run fast while wearing asbestos suits and full-face
> protective helmets. *If you've never had to deal with a bucket of
> burning molten sodium, you've never lived! *(Hint - water isn't
> terribly useful!) *You probably wouldn't want any quantity of burning
> (molten or otherwise) lithium near you or in your glider either.
>
> Lithium is WAY too close to the reactive end of the periodic table
> (right up there with sodium, magnesium and potassium).
>
> MIke

Mike,
I have no problem with considering Li-Ion's to be unsafe and to have
no place in a glider, but I don't understand having that opinion and
then flying with 1 to 3 of them. That was why I burned up an Ipaq
battery, to see if they are too small to cause a problem. My
conclusion is that anything from 800 mAH or larger, and probably
smaller, will make a glider uninhabitable.

But perhaps a better way of getting a handle on the risk is to look at
the incident rate, said to be about 100 cell phones fires between 2002
to 2004, out of more than 200 million cell phones are in use. This is
consistent with a fire risk of something like 1 in 4 million per year
of use for 'good' batteries and 1 in 200,000 for defective ones.

Laptop fires:
There were two recalls, the first of 9.7 million laptops after 16
fires, the other of under 6 million after 50 fires. This was for
defective units with metal particles that internally shorted out the
battery.

More info here:
http://www.consumeraffairs.com/news04/2007/01/cell_fire02.html#ixzz157SfeqzG

and here:
http://www.buchmann.ca/article28-page1.asp

Really I am not trying to convince anyone that Li-Ions are safe, I
thought it would be helpful to have a discussion about them. The most
valuable fact for me was the existence of the 15AH lead acid unit.

Brian

[Eric Greenwell[_4_]]

On 11/13/2010 2:33 PM, brianDG303 wrote:
>
> Mike,
> I have no problem with considering Li-Ion's to be unsafe and to have
> no place in a glider, but I don't understand having that opinion and
> then flying with 1 to 3 of them. That was why I burned up an Ipaq
> battery, to see if they are too small to cause a problem. My
> conclusion is that anything from 800 mAH or larger, and probably
> smaller, will make a glider uninhabitable.
>
> But perhaps a better way of getting a handle on the risk is to look at
> the incident rate, said to be about 100 cell phones fires between 2002
> to 2004, out of more than 200 million cell phones are in use. This is
> consistent with a fire risk of something like 1 in 4 million per year
> of use for 'good' batteries and 1 in 200,000 for defective ones.
>
> Laptop fires:
> There were two recalls, the first of 9.7 million laptops after 16
> fires, the other of under 6 million after 50 fires. This was for
> defective units with metal particles that internally shorted out the
> battery.
>
> More info here:
> http://www.consumeraffairs.com/news04/2007/01/cell_fire02.html#ixzz157SfeqzG
>
> and here:
> http://www.buchmann.ca/article28-page1.asp
>
> Really I am not trying to convince anyone that Li-Ions are safe, I
> thought it would be helpful to have a discussion about them. The most
> valuable fact for me was the existence of the 15AH lead acid unit.
>
I think there are some important differences between the Li-ion
batteries used in consumer products and those we are contemplating using
in our gliders:

* the cell phone, laptop, power tool batteries are high volume
production products. My guess is they are likely more consistent
in quality than buying hand assembled, small batch (or only
one-at-a-time) units.
* they all have dedicated, proprietary chargers that plug in to only
their intended battery
* they store much more energy than a laptop battery, and far more
than a cell phone battery, so even be a small problem is likely
turn in to a bigger problem than the cell phone/laptop battery.
* the high volumes make good engineering and testing of the designs
for the battery, it's protection circuitry, and it's charger
relatively cheap per unit
* they aren't subjected to the low pressures of 18K and higher that
many of us routinely achieve.

The high price will keep most pilots from buying one, so I'm not too
worried about imminent fireballs on the end of a tow rope. It does seem
prudent to consider Li-ion only if you really, really, need to save a
few pounds or increase the capacity a few amphours, then buy it from a
reputable supplier (not the cheapest), and pay strict attention to the
charging procedures.


--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

[jcarlyle]

When I found that my cell phone and my iPAQ had Li-Ion batteries that
were 1 to 3 times the 800 mAH size that Brian feels could “make a
glider uninhabitable”, I got motivated to look into what might cause a
problem with Li-Ion.

An EPA technical article said Li-Ion batteries were safe <only> if
they operated in a small range of voltage and temperature (cell
voltage between 2.0 to 4.2 volts, and cell temperature between 0 to
120 degrees C). Charging outside of this range causes most problems,
but high temperatures can cause thermal runaway spontaneously.
Underwriters Laboratories specifies Li-Ion battery tests that over-
charge, short circuit, puncture, and over heat - they want to see no
explosions or burning result. Shippers have to pack Li-Ion batteries
so they are protected from damage and short circuit, and if they’re in
a device it <cannot> accidentally turn on during shipment.

As the Buchmann article Brian referenced pointed out, Li-Ion
manufacturers try to achieve reliability by including safety
mechanisms within the cell, and by adding protection circuits within
the battery pack. But the protection circuits can be destroyed without
the user knowing, via static electricity or a faulty charger. Further,
internal defects can occur that might defeat the cell safety
mechanisms. The massive Dell/Apple battery recall was for Li-Ion
batteries made by Sony, whose batteries were contaminated internally
during manufacture with microscopic metal particles. It was possible
for the metal particles to trigger thermal runaway (also referred to
as “venting with flame”) that cannot be stopped once it starts.

For us glider pilots I conclude we’re probably OK as long as we don’t
fly with dropped or damaged cell phones and/or iPAQs. It would also be
a good idea to turn your cell phone turned of during flight.

But one big problem for us glider pilots is that we’re charging our
iPAQ’s Li-Ion cells while flying, and there’s a problem if repeated
charging occurs below 0 degrees C. Metallic lithium will plate the
inside of the cell, which causes the cell to be more vulnerable to
thermal runaway if it is subjected to impact, crushing or high rate
charging (like maybe if you run your iPAQ down and then connect it to
the ship’s power). For those of you who fly in real cold weather or
who fly at high alititudes, be aware.

-John

[Martin Gregorie[_5_]]

On Sun, 14 Nov 2010 08:04:47 -0800, jcarlyle wrote:

> But one big problem for us glider pilots is that we’re charging our
> iPAQ’s Li-Ion cells while flying, and there’s a problem if repeated
> charging occurs below 0 degrees C. Metallic lithium will plate the
> inside of the cell, which causes the cell to be more vulnerable to
> thermal runaway if it is subjected to impact, crushing or high rate
> charging (like maybe if you run your iPAQ down and then connect it to
> the ship’s power). For those of you who fly in real cold weather or who
> fly at high alititudes, be aware.
>
A very interesting description of what can cause a thermal runaway.
Thanks.

I use a Binatone PNA to run LK8000 and have a couple of questions:

- when a PNA or PDA is running normally, how warm is the internal
Li-ion battery, i.e. what are the limits on the battery staying
warm enough to keep it above zero?

- Is there any way of using these things that minimises the chances
of damaging the battery?

From what you say, running the PNA well down before plugging it to
charge it isn't so clever at low temperatures. I keep mine fully
charged when its out of the glider and its always connected to the
charger when I'm flying with it. Is this the best way of keeping the
battery warm and happy?


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

[jcarlyle]

Martin, you're welcome.

I wish I could answer your first question, but I cannot. I suspect it
depends heavily on how insulating the PNA case is, how much current
the PNA draws, and how much heat the PNA's backlight and other
circuitry generates. You'll need to experiment to find out, I'm
afraid. And then you've still got some leeway, probably, because I
suspect that the lithium plating doesn't start immediately at 0C and
it will also depend on the charging current.

As for your second question, what you propose is exactly what I think
you should do. I keep my iPAQ on charge at home and also charge it in
my car until just before I put it in the cockpit, when the ship's
power takes over keeping the charge up.

-John

On Nov 14, 3:29 pm, Martin Gregorie >
wrote:
> A very interesting description of what can cause a thermal runaway.
> Thanks.
>
> I use a Binatone PNA to run LK8000 and have a couple of questions:
>
> - when a PNA or PDA is running normally, how warm is the internal
> Li-ion battery, i.e. what are the limits on the battery staying
> warm enough to keep it above zero?
>
> - Is there any way of using these things that minimises the chances
> of damaging the battery?
>
> From what you say, running the PNA well down before plugging it to
> charge it isn't so clever at low temperatures. I keep mine fully
> charged when its out of the glider and its always connected to the
> charger when I'm flying with it. Is this the best way of keeping the
> battery warm and happy?

[Martin Gregorie[_5_]]

On Sun, 14 Nov 2010 13:33:59 -0800, jcarlyle wrote:

> I wish I could answer your first question, but I cannot. I suspect it
> depends heavily on how insulating the PNA case is, how much current the
> PNA draws, and how much heat the PNA's backlight and other circuitry
> generates. You'll need to experiment to find out, I'm afraid. And then
> you've still got some leeway, probably, because I suspect that the
> lithium plating doesn't start immediately at 0C and it will also depend
> on the charging current.
>
Now I think about it, I have a sort of partial, vague, sort-of datapoint.

Recently The staff members of The Register, an online technical mag,
dropped a paper aeroplane from 89,500 ft using a large weather balloon.
It also carried payload in the shape of a box made from thick foam and
containing a GPS tracker, a video camera, a still camera that took a
photo every 10 secs and at least one chemical hand-warmer. The still
camera quit on the way up at the cloud tops but the video ran for the
whole flight, which lasted around 2.5 hours, so (surprise!) it looks as
if you need a reasonable current drain to keep the battery warm.
Unfortunately the mission wasn't instrumented enough to record
temperature and the flight trace has no timestamps. Details are here if
you're interested:

http://www.theregister.co.uk/science/paris/

> As for your second question, what you propose is exactly what I think
> you should do. I keep my iPAQ on charge at home and also charge it in my
> car until just before I put it in the cockpit, when the ship's power
> takes over keeping the charge up.
>
That's good to know. Thanks.


--
martin@ | Martin Gregorie
gregorie. | Essex, UK
org |

[Mike Ash]

In article >,
Eric Greenwell > wrote:

> * the cell phone, laptop, power tool batteries are high volume
> production products. My guess is they are likely more consistent
> in quality than buying hand assembled, small batch (or only
> one-at-a-time) units.
> * they all have dedicated, proprietary chargers that plug in to only
> their intended battery

Are you referring to internal charging circuitry with this last item?
Because many (most?) cell phones will charge off any standard USB port,
as long as you have the appropriate cable (and many can use a standard
USB cable for it). I believe the batteries themselves have enough
circuitry that the external charger doesn't need to be all that good to
keep things safe.

I agree with your point overall. While I carry my cell phone with me in
flight without a second thought, I'd be hesitant to have an order of
magnitude more battery capacity on board in Li-ion form.

--
Mike Ash
Radio Free Earth
Broadcasting from our climate-controlled studios deep inside the Moon

[bildan]

On Nov 14, 5:32*pm, Mike Ash > wrote:
> In article >,
> *Eric Greenwell > wrote:
>
> > * * * the cell phone, laptop, power tool batteries are high volume
> > * * * production products. My guess is they are likely more consistent
> > * * * in quality than buying hand assembled, small batch (or only
> > * * * one-at-a-time) units.
> > * * * they all have dedicated, proprietary chargers that plug in to only
> > * * * their intended battery
>
> Are you referring to internal charging circuitry with this last item?
> Because many (most?) cell phones will charge off any standard USB port,
> as long as you have the appropriate cable (and many can use a standard
> USB cable for it). I believe the batteries themselves have enough
> circuitry that the external charger doesn't need to be all that good to
> keep things safe.
>
> I agree with your point overall. While I carry my cell phone with me in
> flight without a second thought, I'd be hesitant to have an order of
> magnitude more battery capacity on board in Li-ion form.
>
> --
> Mike Ash
> Radio Free Earth
> Broadcasting from our climate-controlled studios deep inside the Moon


Lithium batteries come in many chemistries - some with problematic
safety, others as safe as any battery can be. To group them all under
the heading "lithium-ion" is at best uninformed. Many of us will soon
be driving around with several hundred pounds of "lithium-ion" in our
cars.

One of the safest and best is "Lithium Iron Phosphate" (LiFePo4)
chemistry. This safety comes at the cost of lower energy density than
is typical of cell-phone or laptop batteries but they are still far
more energy dense than any lead battery. They also have a discharge
voltage curve which allows full use of their capacity.

[Eric Greenwell[_4_]]

On 11/14/2010 4:32 PM, Mike Ash wrote:
> In >,
> Eric > wrote:
>
>
>> * the cell phone, laptop, power tool batteries are high volume
>> production products. My guess is they are likely more consistent
>> in quality than buying hand assembled, small batch (or only
>> one-at-a-time) units.
>> * they all have dedicated, proprietary chargers that plug in to only
>> their intended battery
>>
> Are you referring to internal charging circuitry with this last item?
> Because many (most?) cell phones will charge off any standard USB port,
> as long as you have the appropriate cable (and many can use a standard
> USB cable for it). I believe the batteries themselves have enough
> circuitry that the external charger doesn't need to be all that good to
> keep things safe.
>
> I agree with your point overall. While I carry my cell phone with me in
> flight without a second thought, I'd be hesitant to have an order of
> magnitude more battery capacity on board in Li-ion form.
>
I'm pretty sure the charge control circuitry is in the cell phone, the
Ipaq, or the laptop itself, not in it's battery, and the "charger" that
plugs into the wall is really only a power supply without a charge
regulator. It's not obvious from my writing, but that's what I meant by
the "proprietary chargers that plug in to only their intended battery".
The cell phone and Ipaq batteries I've seen are single cell units;
laptop batteries are multiple cell in series (and some are multiple
series units in parallel).

The K2 battery in the Soaring article looks interesting, and is closest
I've seen to a drop-in replacement, but the datasheet was sparse. It
didn't go into what protection circuitry was installed in the box, or
what the charger was like. It seems very "one-off" to me, and I'd like
more data and more field history before committing to one.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarm http://tinyurl.com/yb3xywl
- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

[brianDG303[_2_]]

The battery in an Ipaq is a flat foil covered package, I wish now that
I had opened up the one I burned. The 12 volt batteries that I was
working with, that I gave a link to, are composed of 3 similar flat
foil packages, each when opened have a long narrow circuit board along
the top. These apparently 'turn off' the battery when you dead short
or put to much load on them and probably have other protective
properties as well. Under some conditions these will fail and at that
point I could never get the battery to work again.

Brian

[noel.wade]

I just wanted to repeat something bildan stated:

THERE ARE MANY TYPES OF LITHIUM BATTERIES.

The term "Li-Ion" gets tossed around a lot, but it is incorrect to
call all Lithium batteries "Li-Ion", just like its incorrect to call
all sealed lead-acid batteries "Gel Cells" (ignoring the differences
between Gel, VRLA, and AGM).

There's the Li-Ion system/chemistry that is used in a lot of consumer
devices (such as what Brian tested). These tend to have a much better
track-record than many of the "Lithium Polymer" batteries (but at a
lower energy density). Some people use "Li-Po" and "Lithium Polymer"
interchangeably; while other groups use "Li-Po" to designate Lithium
Phosphate formulations.

And to make matters worse, "Li-Po" and "Lithium Polymer" batteries
themselves are now coming in different formulations. The earlier
"flat rectangle" cells from makers like Kokam were cutting edge for
awhile and used by many in the R/C modeling world; but have proven to
be highly flammable under high charge/discharge loads. One of the
telltale signs for these cells is that they provide 3.7 volts per cell
(a slightly awkward voltage for many applications).

Different Lithium formulations tend to provide slightly different
voltage on a per-cell basis. No particular per-cell voltage equates
to safety - but its a handy way to check what kind of cells you're
getting if the manufacturer isn't really specific about which brand or
formulation is being used inside the battery pack.

The LiFePo4 that is discussed in the Soaring magazine article is one
particular formulation. I haven't had a chance to research it in
detail, but it does look safer than some other "Li-Po" systems. If
the price comes down I'd certainly consider buying the new cells; but
as Brian pointed out the newer high-density SLA cells are pretty nice
for the price!

--Noel

[Matt Herron Jr.]

On Nov 15, 2:49*pm, "noel.wade" > wrote:
> I just wanted to repeat something bildan stated:
>
> THERE ARE MANY TYPES OF LITHIUM BATTERIES.
>
> The term "Li-Ion" gets tossed around a lot, but it is incorrect to
> call all Lithium batteries "Li-Ion", just like its incorrect to call
> all sealed lead-acid batteries "Gel Cells" (ignoring the differences
> between Gel, VRLA, and AGM).
>
> There's the Li-Ion system/chemistry that is used in a lot of consumer
> devices (such as what Brian tested). *These tend to have a much better
> track-record than many of the "Lithium Polymer" batteries (but at a
> lower energy density). *Some people use "Li-Po" and "Lithium Polymer"
> interchangeably; while other groups use "Li-Po" to designate Lithium
> Phosphate formulations.
>
> And to make matters worse, "Li-Po" and "Lithium Polymer" batteries
> themselves are now coming in different formulations. *The earlier
> "flat rectangle" cells from makers like Kokam were cutting edge for
> awhile and used by many in the R/C modeling world; but have proven to
> be highly flammable under high charge/discharge loads. *One of the
> telltale signs for these cells is that they provide 3.7 volts per cell
> (a slightly awkward voltage for many applications).
>
> Different Lithium formulations tend to provide slightly different
> voltage on a per-cell basis. *No particular per-cell voltage equates
> to safety - but its a handy way to check what kind of cells you're
> getting if the manufacturer isn't really specific about which brand or
> formulation is being used inside the battery pack.
>
> The LiFePo4 that is discussed in the Soaring magazine article is one
> particular formulation. *I haven't had a chance to research it in
> detail, but it does look safer than some other "Li-Po" systems. *If
> the price comes down I'd certainly consider buying the new cells; but
> as Brian pointed out the newer high-density SLA cells are pretty nice
> for the price!
>
> --Noel

Is there any info on performance of these technologies relative to
each other in freezing temperatures?

[bildan]

On Nov 15, 7:59*pm, "Matt Herron Jr." > wrote:
> On Nov 15, 2:49*pm, "noel.wade" > wrote:
>
>
>
> > I just wanted to repeat something bildan stated:
>
> > THERE ARE MANY TYPES OF LITHIUM BATTERIES.
>
> > The term "Li-Ion" gets tossed around a lot, but it is incorrect to
> > call all Lithium batteries "Li-Ion", just like its incorrect to call
> > all sealed lead-acid batteries "Gel Cells" (ignoring the differences
> > between Gel, VRLA, and AGM).
>
> > There's the Li-Ion system/chemistry that is used in a lot of consumer
> > devices (such as what Brian tested). *These tend to have a much better
> > track-record than many of the "Lithium Polymer" batteries (but at a
> > lower energy density). *Some people use "Li-Po" and "Lithium Polymer"
> > interchangeably; while other groups use "Li-Po" to designate Lithium
> > Phosphate formulations.
>
> > And to make matters worse, "Li-Po" and "Lithium Polymer" batteries
> > themselves are now coming in different formulations. *The earlier
> > "flat rectangle" cells from makers like Kokam were cutting edge for
> > awhile and used by many in the R/C modeling world; but have proven to
> > be highly flammable under high charge/discharge loads. *One of the
> > telltale signs for these cells is that they provide 3.7 volts per cell
> > (a slightly awkward voltage for many applications).
>
> > Different Lithium formulations tend to provide slightly different
> > voltage on a per-cell basis. *No particular per-cell voltage equates
> > to safety - but its a handy way to check what kind of cells you're
> > getting if the manufacturer isn't really specific about which brand or
> > formulation is being used inside the battery pack.
>
> > The LiFePo4 that is discussed in the Soaring magazine article is one
> > particular formulation. *I haven't had a chance to research it in
> > detail, but it does look safer than some other "Li-Po" systems. *If
> > the price comes down I'd certainly consider buying the new cells; but
> > as Brian pointed out the newer high-density SLA cells are pretty nice
> > for the price!
>
> > --Noel
>
> Is there any info on performance of these technologies relative to
> each other in freezing temperatures?

Lot's of info in the manufacturer's spec sheets. Cold weather
performance is critical for EV batteries. New announcements are being
made daily. New technology batteries are complex and it's best to
avoid generalities.

The rule of thumb for EV's is you lose ~10% range starting out on a
freezing day but much of that is recovered as the battery pack "self-
warms" from the current draw.

It's likely the same for glider batteries - you launch with the
battery in use and the internal electrochemical reactions generate
enough heat to avoid the worst of low temperature effects.

[GeorgeB]

On Mon, 15 Nov 2010 14:49:06 -0800 (PST), "noel.wade"
> wrote:

>The LiFePo4 that is discussed ...

vent mode on ...

I know that many folks think m=M (milihertz megahertz)(mHz MHz) but
why does anyone use the chemical symbol for polonium in the lithium
iron phosphate batteries?

I guess it looks better to have a pattern?

LiFePO4 (technically the 4 should be a subscript, but that is
reasonable within the limits of ASCII) is the correct formula. PO4 is
phosphate.

vent mode off, sorry ...

[sisu1a]

> LiFePO4 (technically the 4 should be a subscript, but that is
> reasonable within the limits of ASCII)

LiFePOâ‚„ ;)