Maybe Lithium batteries in gliders not quite such a good idea yet?

Like Terry, I reiterate there's a confusion between Polymer and Phosphate.
I have three 10AH LiFePO4 in my glider.
It takes more than lead acid to make long flights with a large moving map display, transponder, com, flarm, and flight computer.
Jim

On Thursday, January 17, 2013 3:22:11 PM UTC-7, wrote:

The problem is I have limited battery tray space and need higher amp hours in the same tray than lead acid can provide.
The problem is that your panel has more toys than an adult novelty shop ;-).. Just use the correct charger/balancer and you will be fine. Another thing for safety and longevity is the cut off circuitry. These have been used in gliders for some time with good results. Look at the Antares (Slight variation in chemistry). Also, Doesn't the JS1 come with LiFePo4 from the factory.

On Thu, 17 Jan 2013 14:39:38 -0800, terry wrote:

Also... The other folks here are right... LiPo are the dangerous
battery. LiFePo4 are quite safe. The chance of an oxygen pocket being
formed are damn near zero.

Here's a bit more on the 878 problem. It includes a photo of the burnt-
out PSU at Boston. Scary.

http://www.theregister.co.uk/2013/01...787_batteries/



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

Bruno,

Several of us use these K2 batteries. They have a "battery management system." The BMS controls the charge and allows it to be charged with a lead acid charger, as long as it gets up to around 14 volts or so. It also controls discharge to prevent battery damage. I guess lithium batteries don't like to be discharged too far. Be sure to get the ones that have "EP" at the end of the number, because they do sell the same without a BMS. They're expensive but have a very flat discharge voltage curve, weigh a lot less and should far outlast our old lead acid batteries in years. By the way, isn't A123 in bankruptcy?

http://store.peakbattery.com/12lfpba.html

And if you want to see one dissected:

http://www.etotheipiplusone.net/?p=1991

On Jan 17, 9:30*pm, gotovkotzepkoi
wrote:
Does anyone know what type of lithium batteries are used in the electric
self launchers like the Taurus or the Antares?

--
gotovkotzepkoi

From Antares web site: http://www.lange-aviation.com/htm/en...ry_system.html.

"The Antares 20E is equipped with a battery-system utilizing Li-Ion
cells of the type SAFT VL41M.".

"As a user of SAFT VL41M cells, Lange Aviation is in good company.
SAFT VL41M are also used in most new European satellites, the RQ-4B
Global Hawk UAV, the F35 Joint Strike Fighter, the Airbus A380 and in
many other high-tech applications.
Next to being a great vote of confidence to SAFT VL41M cells, the
military implementations mean that the cells which are now being built
into the Antares 20E will be available at least until 2031."

Charlie

On Friday, January 18, 2013 4:27:09 AM UTC-6, cfinn wrote:
On Jan 17, 9:30*pm, gotovkotzepkoi

wrote:

Does anyone know what type of lithium batteries are used in the electric

self launchers like the Taurus or the Antares?



--

gotovkotzepkoi



From Antares web site: http://www.lange-aviation.com/htm/en...ry_system.html.



"The Antares 20E is equipped with a battery-system utilizing Li-Ion

cells of the type SAFT VL41M.".



"As a user of SAFT VL41M cells, Lange Aviation is in good company.

SAFT VL41M are also used in most new European satellites, the RQ-4B

Global Hawk UAV, the F35 Joint Strike Fighter, the Airbus A380 and in

many other high-tech applications.

Next to being a great vote of confidence to SAFT VL41M cells, the

military implementations mean that the cells which are now being built

into the Antares 20E will be available at least until 2031."



Charlie

A further advantage of LiFePo batteries is the higher current they can take when charging. I charge my 8.4 Ah 4-cell battery with 4A on a balancing charger. The fuse on the battery is 5A so I could easily go a little higher. According to the spec sheet the charge current could be as high as 16A (2C)

Thanks everyone for the great info and quick replies. I received a very helpful email from someone who reminded me that in the Boeing situation these batteries are not just being drawn down but also charged during use. I can see how that makes a huge difference compared to just drawing down during the flight.

A question and concern from looking at some of these batteries mentioned. In the specs and warnings the manufacturers are warning against submerging these batteries. I don't plan on landing in any water soon but I have heard of gliders having their ballast leak into the rear deck and cockpit. I heard of a 29 doing this so maybe my 27 could possibly have this happen as well. When the batteries get submerged back there and short out. Then what?

Thanks for your patience with us guys lagging behind in so many ways.

Bruno - B4

On 1/18/2013 7:00 AM, wrote:
On Friday, January 18, 2013 4:27:09 AM UTC-6, cfinn wrote:

"As a user of SAFT VL41M cells, Lange Aviation is in good company.

SAFT VL41M are also used in most new European satellites, the
RQ-4B

Global Hawk UAV, the F35 Joint Strike Fighter, the Airbus A380 and
in

many other high-tech applications.

Next to being a great vote of confidence to SAFT VL41M cells, the

military implementations mean that the cells which are now being
built

into the Antares 20E will be available at least until 2031."

Charlie

A further advantage of LiFePo batteries is the higher current they
can take when charging. I charge my 8.4 Ah 4-cell battery with 4A on
a balancing charger. The fuse on the battery is 5A so I could easily
go a little higher. According to the spec sheet the charge current
could be as high as 16A (2C)

The Antares cells are Li-ion, in case anyone was wondering.

I like the idea of LiFePO4 batteries, but I'm not comfortable with the
commercial offerings, like those from Tenergy or K2. The data sheets
I've been able to obtain are incomplete compared to what I can get for
any of the comparable SLA batteries by manufacturers like PowerSonic,
Yuasa, Panasonic, and so on. The idea of paying 7 to 10 times as much
for a complex, poorly characterized battery is not enticing.

If I could buy a direct replacement 12 volt LiFePO4 battery from one the
major battery companies, with a full datasheet, then I'd think about it,
and would be much more comfortable suggesting them for other pilots.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to
email me)

Hi Bruno,

29's have a small plug at the wing root that can be left open while the
glider is in the trailer to allow leftover water to evaporate from the
tanks. I have seen a few 29 drivers forget this plug while they fill
the glider and end up having water in their cockpit. The 27's do not
have this as far as I know so it may not be an issue.

Luke

On 01/18/2013 10:50 AM, wrote:
Thanks everyone for the great info and quick replies. I received a very helpful email from someone who reminded me that in the Boeing situation these batteries are not just being drawn down but also charged during use. I can see how that makes a huge difference compared to just drawing down during the flight.

A question and concern from looking at some of these batteries mentioned. In the specs and warnings the manufacturers are warning against submerging these batteries. I don't plan on landing in any water soon but I have heard of gliders having their ballast leak into the rear deck and cockpit. I heard of a 29 doing this so maybe my 27 could possibly have this happen as well. When the batteries get submerged back there and short out. Then what?

Thanks for your patience with us guys lagging behind in so many ways.

Bruno - B4

As I noted in an earlier post, lithium is a bit less reactive than sodium - however, it reacts strongly with water to produce hydrogen and can self-ignite. I'd only consider having any battery with lithium in a glider if it were in a form that severely inhibits this behavior.

Mike