a Li-Ion in a lead acid world.

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 he

http://www.dinodirect.com/Super-9000...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

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

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

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

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

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

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/al...attery-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

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 he

http://www.dinodirect.com/Super-9000...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)

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 he

http://www.dinodirect.com/Super-9000...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

The Li-Ion battery I ended up with is he
http://www.dinodirect.com/Super-9000...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/128vlife...terypacks.aspx I know some
folks using batteries/chargers from these guys are are quite happy
with them... many options at many pricepoints...

-Paul