Battery safety (againish)

[Jonathan St. Cloud]

Was wondering if others had read and were doing this:
https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf

The ASG-29E has a gas tank directly above two batteries used to power flight instruments.

[kinsell]

On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
> Was wondering if others had read and were doing this:
> https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
>
> The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
>

Interesting that they say to add epoxy to the casing. Putting a fuse at
one of the battery terminals would be a more conventional way of
handling it, and would allow for easier battery replacement.

[Andrzej Kobus]

On Saturday, March 16, 2019 at 1:04:19 PM UTC-4, kinsell wrote:
> On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
> > Was wondering if others had read and were doing this:
> > https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
> >
> > The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
> >
>
> Interesting that they say to add epoxy to the casing. Putting a fuse at
> one of the battery terminals would be a more conventional way of
> handling it, and would allow for easier battery replacement.

You are missing the point. The fuse will not protect against internal short.

[kinsell]

On 3/16/19 1:10 PM, Andrzej Kobus wrote:
> On Saturday, March 16, 2019 at 1:04:19 PM UTC-4, kinsell wrote:
>> On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
>>> Was wondering if others had read and were doing this:
>>> https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
>>>
>>> The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
>>>
>>
>> Interesting that they say to add epoxy to the casing. Putting a fuse at
>> one of the battery terminals would be a more conventional way of
>> handling it, and would allow for easier battery replacement.
>
> You are missing the point. The fuse will not protect against internal short.
>

No, not missing the point. The way I read it, they're talking about an
battery holder added around the battery. You wouldn't normally call
internal wiring "battery cables". Maybe something got lost in translation.

If anybody is using a battery so poorly constructed that it shorts out
internally and catches fire, that battery should be discarded immediately.

[Andrzej Kobus]

On Saturday, March 16, 2019 at 7:35:22 PM UTC-4, kinsell wrote:
> On 3/16/19 1:10 PM, Andrzej Kobus wrote:
> > On Saturday, March 16, 2019 at 1:04:19 PM UTC-4, kinsell wrote:
> >> On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
> >>> Was wondering if others had read and were doing this:
> >>> https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
> >>>
> >>> The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
> >>>
> >>
> >> Interesting that they say to add epoxy to the casing. Putting a fuse at
> >> one of the battery terminals would be a more conventional way of
> >> handling it, and would allow for easier battery replacement.
> >
> > You are missing the point. The fuse will not protect against internal short.
> >
>
> No, not missing the point. The way I read it, they're talking about an
> battery holder added around the battery. You wouldn't normally call
> internal wiring "battery cables". Maybe something got lost in translation.
>
> If anybody is using a battery so poorly constructed that it shorts out
> internally and catches fire, that battery should be discarded immediately.

They are not adding a housing they are internally fixing it with PU resin because they had internal short circuit.

[Dan Marotta]

Some, maybe all LiFePO4 batteries are made up of individual cells wired
together in series to make up the full voltage.Â* If that setup is simply
stuffed into a plastic case and not secured, things can rattle around,
possibly allowing uninsulated interconnecting wires to short together.Â*
I might try stuffing foam into the battery case rather than filling it
with resin.Â* A fuse on the output cable should be considered mandatory.

On 3/16/2019 6:34 PM, Andrzej Kobus wrote:
> On Saturday, March 16, 2019 at 7:35:22 PM UTC-4, kinsell wrote:
>> On 3/16/19 1:10 PM, Andrzej Kobus wrote:
>>> On Saturday, March 16, 2019 at 1:04:19 PM UTC-4, kinsell wrote:
>>>> On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
>>>>> Was wondering if others had read and were doing this:
>>>>> https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
>>>>>
>>>>> The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
>>>>>
>>>> Interesting that they say to add epoxy to the casing. Putting a fuse at
>>>> one of the battery terminals would be a more conventional way of
>>>> handling it, and would allow for easier battery replacement.
>>> You are missing the point. The fuse will not protect against internal short.
>>>
>> No, not missing the point. The way I read it, they're talking about an
>> battery holder added around the battery. You wouldn't normally call
>> internal wiring "battery cables". Maybe something got lost in translation.
>>
>> If anybody is using a battery so poorly constructed that it shorts out
>> internally and catches fire, that battery should be discarded immediately.
> They are not adding a housing they are internally fixing it with PU resin because they had internal short circuit.

--
Dan, 5J

[Jonathan St. Cloud]

On Saturday, March 16, 2019 at 4:35:22 PM UTC-7, kinsell wrote:
> On 3/16/19 1:10 PM, Andrzej Kobus wrote:
> > On Saturday, March 16, 2019 at 1:04:19 PM UTC-4, kinsell wrote:
> >> On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
> >>> Was wondering if others had read and were doing this:
> >>> https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
> >>>
> >>> The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
> >>>
> >>
> >> Interesting that they say to add epoxy to the casing. Putting a fuse at
> >> one of the battery terminals would be a more conventional way of
> >> handling it, and would allow for easier battery replacement.
> >
> > You are missing the point. The fuse will not protect against internal short.
> >
>
> No, not missing the point. The way I read it, they're talking about an
> battery holder added around the battery. You wouldn't normally call
> internal wiring "battery cables". Maybe something got lost in translation.
>
> If anybody is using a battery so poorly constructed that it shorts out
> internally and catches fire, that battery should be discarded immediately.

The way I read it is a small hole is drilled in the case and resin injected...?

[[email protected]]

On Saturday, March 16, 2019 at 8:34:16 PM UTC-4, Andrzej Kobus wrote:
> On Saturday, March 16, 2019 at 7:35:22 PM UTC-4, kinsell wrote:
> > On 3/16/19 1:10 PM, Andrzej Kobus wrote:
> > > On Saturday, March 16, 2019 at 1:04:19 PM UTC-4, kinsell wrote:
> > >> On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
> > >>> Was wondering if others had read and were doing this:
> > >>> https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
> > >>>
> > >>> The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
> > >>>
> > >>
> > >> Interesting that they say to add epoxy to the casing. Putting a fuse at
> > >> one of the battery terminals would be a more conventional way of
> > >> handling it, and would allow for easier battery replacement.
> > >
> > > You are missing the point. The fuse will not protect against internal short.
> > >
> >
> > No, not missing the point. The way I read it, they're talking about an
> > battery holder added around the battery. You wouldn't normally call
> > internal wiring "battery cables". Maybe something got lost in translation.
> >
> > If anybody is using a battery so poorly constructed that it shorts out
> > internally and catches fire, that battery should be discarded immediately.
>
> They are not adding a housing they are internally fixing it with PU resin because they had internal short circuit.

Many of us are flying with multi-cell LiFePO4 batteries that have internal wiring and are not filled with resin. Is that a problem? Or is the location of the batteries in this specific glider such that the resin is advisable? A battery fire anywhere in a glider (even without a fuel tank) is catastrophic. OTOH I havn't heard of any fires with this type of battery. It's the lithium-polymer battery pack (also much larger, with many more cells) in the FES systems that has had fires.

[kinsell]

On 3/16/19 9:31 PM, wrote:
> On Saturday, March 16, 2019 at 8:34:16 PM UTC-4, Andrzej Kobus wrote:
>> On Saturday, March 16, 2019 at 7:35:22 PM UTC-4, kinsell wrote:
>>> On 3/16/19 1:10 PM, Andrzej Kobus wrote:
>>>> On Saturday, March 16, 2019 at 1:04:19 PM UTC-4, kinsell wrote:
>>>>> On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
>>>>>> Was wondering if others had read and were doing this:
>>>>>> https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
>>>>>>
>>>>>> The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
>>>>>>
>>>>>
>>>>> Interesting that they say to add epoxy to the casing. Putting a fuse at
>>>>> one of the battery terminals would be a more conventional way of
>>>>> handling it, and would allow for easier battery replacement.
>>>>
>>>> You are missing the point. The fuse will not protect against internal short.
>>>>
>>>
>>> No, not missing the point. The way I read it, they're talking about an
>>> battery holder added around the battery. You wouldn't normally call
>>> internal wiring "battery cables". Maybe something got lost in translation.
>>>
>>> If anybody is using a battery so poorly constructed that it shorts out
>>> internally and catches fire, that battery should be discarded immediately.
>>
>> They are not adding a housing they are internally fixing it with PU resin because they had internal short circuit.
>
> Many of us are flying with multi-cell LiFePO4 batteries that have internal wiring and are not filled with resin. Is that a problem? Or is the location of the batteries in this specific glider such that the resin is advisable? A battery fire anywhere in a glider (even without a fuel tank) is catastrophic. OTOH I havn't heard of any fires with this type of battery. It's the lithium-polymer battery pack (also much larger, with many more cells) in the FES systems that has had fires.
>

Well, the service bulletin talks about an LFP that burned. There was a
fire in an EB-28 in Finland last year with a 10 A-H LFP. Here's a video
of an LFP burning:

https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/

There have been claims that LFP's don't burn, but that's simply not true.

[bumper[_4_]]

On Saturday, March 16, 2019 at 8:31:57 PM UTC-7, wrote:

>
> Many of us are flying with multi-cell LiFePO4 batteries that have internal wiring and are not filled with resin. Is that a problem? Or is the location of the batteries in this specific glider such that the resin is advisable? A battery fire anywhere in a glider (even without a fuel tank) is catastrophic. OTOH I havn't heard of any fires with this type of battery. It's the lithium-polymer battery pack (also much larger, with many more cells) in the FES systems that has had fires.

Probably not if a self launch is electric or has a Wankel engine that isn't doing its best to rattle your teeth fillings loose. With an engine that could pass for a paint mixer, the resin may keep things from rattling enough to chafe and perhaps short the battery internals.

[Eric Greenwell[_4_]]

kinsell wrote on 3/16/2019 9:46 PM:

>>
>> Many of us are flying with multi-cell LiFePO4 batteries that have internal
>> wiring and are not filled with resin.* Is that a problem?* Or is the location of
>> the batteries in this specific glider such that the resin is advisable?* A
>> battery fire anywhere in a glider (even without a fuel tank) is catastrophic.
>> OTOH I havn't heard of any fires with this type of battery.* It's the
>> lithium-polymer battery pack (also much larger, with many more cells) in the FES
>> systems that has had fires.
>>
>
> Well, the service bulletin talks about an LFP that burned.* There was a fire in an
> EB-28 in Finland last year with a 10 A-H LFP.* Here's a video of an LFP burning:
>
> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
>
>
> There have been claims that LFP's don't burn, but that's simply not true.

The Aerovoltz battery that burned did not have a BMS; in fact, none of the
Aerovoltz batteries have a BMS (battery management system). I would not want to
use one, even though the short engine runs typical of self-launchers means
problems would be less likely than in airplanes. The Earth-X batteries all have a
BMS, seem better characterized, and I would trust them a lot more.

--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/Guide-to-transponders-in-sailplanes-2014A.pdf

[Dan Marotta]

I used LiFePO4 batteries in my former LAK-17a for about 3 years before
selling the glider.Â* I charged them out of the glider for the first year
and, thereafter, left them on the provided smart chargers in the glider
between flights.Â* They had battery management systems built-in.Â* Of
course, there's practically no vibration in a pure glider...

On 3/17/2019 9:54 PM, Eric Greenwell wrote:
> kinsell wrote on 3/16/2019 9:46 PM:
>
>>>
>>> Many of us are flying with multi-cell LiFePO4 batteries that have
>>> internal wiring and are not filled with resin.Â* Is that a problem?Â*
>>> Or is the location of the batteries in this specific glider such
>>> that the resin is advisable?Â* A battery fire anywhere in a glider
>>> (even without a fuel tank) is catastrophic.Â* OTOH I havn't heard of
>>> any fires with this type of battery.Â* It's the lithium-polymer
>>> battery pack (also much larger, with many more cells) in the FES
>>> systems that has had fires.
>>>
>>
>> Well, the service bulletin talks about an LFP that burned. There was
>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
>> video of an LFP burning:
>>
>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
>>
>>
>> There have been claims that LFP's don't burn, but that's simply not
>> true.
>
> The Aerovoltz battery that burned did not have a BMS; in fact, none of
> the Aerovoltz batteries have a BMS (battery management system). I
> would not want to use one, even though the short engine runs typical
> of self-launchers means problems would be less likely than in
> airplanes. The Earth-X batteries all have a BMS, seem better
> characterized, and I would trust them a lot more.
>

--
Dan, 5J

[2G]

On Monday, March 18, 2019 at 8:22:43 AM UTC-7, Dan Marotta wrote:
> I used LiFePO4 batteries in my former LAK-17a for about 3 years before
> selling the glider.Â* I charged them out of the glider for the first year
> and, thereafter, left them on the provided smart chargers in the glider
> between flights.Â* They had battery management systems built-in.Â* Of
> course, there's practically no vibration in a pure glider...
>
> On 3/17/2019 9:54 PM, Eric Greenwell wrote:
> > kinsell wrote on 3/16/2019 9:46 PM:
> >
> >>>
> >>> Many of us are flying with multi-cell LiFePO4 batteries that have
> >>> internal wiring and are not filled with resin.Â* Is that a problem?Â*
> >>> Or is the location of the batteries in this specific glider such
> >>> that the resin is advisable?Â* A battery fire anywhere in a glider
> >>> (even without a fuel tank) is catastrophic.Â* OTOH I havn't heard of
> >>> any fires with this type of battery.Â* It's the lithium-polymer
> >>> battery pack (also much larger, with many more cells) in the FES
> >>> systems that has had fires.
> >>>
> >>
> >> Well, the service bulletin talks about an LFP that burned. There was
> >> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
> >> video of an LFP burning:
> >>
> >> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
> >>
> >>
> >> There have been claims that LFP's don't burn, but that's simply not
> >> true.
> >
> > The Aerovoltz battery that burned did not have a BMS; in fact, none of
> > the Aerovoltz batteries have a BMS (battery management system). I
> > would not want to use one, even though the short engine runs typical
> > of self-launchers means problems would be less likely than in
> > airplanes. The Earth-X batteries all have a BMS, seem better
> > characterized, and I would trust them a lot more.
> >
>
> --
> Dan, 5J

Of all of the articles and papers I have read on rechargeable batteries, this is the first one that talked about modifying the internal construction of the battery. The mere idea of drilling into a battery scares the hell out of me, and I bet it would do the same to the manufacturer.

Tom

[SF]

I cut one of my K2 batteries open, after one of the cells in it failed. There's not a lot of space available in there for foam, or drill bits.

-nick one of the cells with a drill and it's going to be bad.
-Equal foam filling is unlikely
-Good possibility of the foam compressing the cells or expanding the case.
-The foam is going to interfere with heat dissipation in a big way, its a pretty good insulator.
-When chasing vibration issues, sometimes tightening up the system makes things worse not better.
-LiFePO batteries don't supply their own oxidizer in a fire, No one ever said they wouldn't catch on fire. Just if they do, they can be put out by depriving them of oxygen. Unlike Lithium ion chemistry batteries which supply their own oxidizer if they catch on fire. So the LiFePO batteries are considered to be a safer battery chemistry, but not a completely safe battery.. A plastic box full of lead plates submerged in sulfuric acid isn't completely safe either.

A LiFePO battery(s) with an internal BMS board, with a fuse right at the battery is the way to go, but treat it with the respect that that much energy stored in a small package deserves.

SF

[[email protected]]

On Saturday, March 16, 2019 at 7:23:21 PM UTC-7, Jonathan St. Cloud wrote:
> On Saturday, March 16, 2019 at 4:35:22 PM UTC-7, kinsell wrote:
> > On 3/16/19 1:10 PM, Andrzej Kobus wrote:
> > > On Saturday, March 16, 2019 at 1:04:19 PM UTC-4, kinsell wrote:
> > >> On 3/16/19 10:05 AM, Jonathan St. Cloud wrote:
> > >>> Was wondering if others had read and were doing this:
> > >>> https://www.dg-flugzeugbau.de/wp-content/uploads/filebase/Data/serviceinfos-en/2019-103-e.pdf
> > >>>
> > >>> The ASG-29E has a gas tank directly above two batteries used to power flight instruments.
> > >>>
> > >>
> > >> Interesting that they say to add epoxy to the casing. Putting a fuse at
> > >> one of the battery terminals would be a more conventional way of
> > >> handling it, and would allow for easier battery replacement.
> > >
> > > You are missing the point. The fuse will not protect against internal short.
> > >
> >
> > No, not missing the point. The way I read it, they're talking about an
> > battery holder added around the battery. You wouldn't normally call
> > internal wiring "battery cables". Maybe something got lost in translation.
> >
> > If anybody is using a battery so poorly constructed that it shorts out
> > internally and catches fire, that battery should be discarded immediately.
>
> The way I read it is a small hole is drilled in the case and resin injected...?

No. Bulletin is suggesting all work is done by the battery manufacturer(Accu-24).

[kinsell]

On 3/17/19 9:54 PM, Eric Greenwell wrote:
> kinsell wrote on 3/16/2019 9:46 PM:
>
>>>
>>> Many of us are flying with multi-cell LiFePO4 batteries that have
>>> internal wiring and are not filled with resin.Â* Is that a problem?
>>> Or is the location of the batteries in this specific glider such that
>>> the resin is advisable?Â* A battery fire anywhere in a glider (even
>>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
>>> fires with this type of battery.Â* It's the lithium-polymer battery
>>> pack (also much larger, with many more cells) in the FES systems that
>>> has had fires.
>>>
>>
>> Well, the service bulletin talks about an LFP that burned.Â* There was
>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
>> video of an LFP burning:
>>
>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
>>
>>
>> There have been claims that LFP's don't burn, but that's simply not true.
>
> The Aerovoltz battery that burned did not have a BMS; in fact, none of
> the Aerovoltz batteries have a BMS (battery management system). I would
> not want to use one, even though the short engine runs typical of
> self-launchers means problems would be less likely than in airplanes.
> The Earth-X batteries all have a BMS, seem better characterized, and I
> would trust them a lot more.
>

Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
redundant BMS boards to make you feel good. Here's a greatpicture of one:

http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/

If you poke around, there's a nice video from the Director of
Engineering at EarthX, he talks about the requirement to have a
gas-tight battery box vented to the outside, to use only a three-phase
alternator to charge it, and to add a crowbar circuit to prevent
over-voltage. Wonder how many glider pilots go to all this trouble?

I think I'll stick to SLA, just press the button and the engine starts
in about a second.


-Dave

P.S. That StewartB in the original thread was a real hoot. Said he
worried more about getting mad cow disease than having trouble with his
EarthX battery. Until his battery went bad. Don't know if he still
eats hamburgers or not.

[2G]

On Tuesday, March 19, 2019 at 10:04:00 PM UTC-7, kinsell wrote:
> On 3/17/19 9:54 PM, Eric Greenwell wrote:
> > kinsell wrote on 3/16/2019 9:46 PM:
> >
> >>>
> >>> Many of us are flying with multi-cell LiFePO4 batteries that have
> >>> internal wiring and are not filled with resin.Â* Is that a problem?
> >>> Or is the location of the batteries in this specific glider such that
> >>> the resin is advisable?Â* A battery fire anywhere in a glider (even
> >>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
> >>> fires with this type of battery.Â* It's the lithium-polymer battery
> >>> pack (also much larger, with many more cells) in the FES systems that
> >>> has had fires.
> >>>
> >>
> >> Well, the service bulletin talks about an LFP that burned.Â* There was
> >> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
> >> video of an LFP burning:
> >>
> >> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
> >>
> >>
> >> There have been claims that LFP's don't burn, but that's simply not true.
> >
> > The Aerovoltz battery that burned did not have a BMS; in fact, none of
> > the Aerovoltz batteries have a BMS (battery management system). I would
> > not want to use one, even though the short engine runs typical of
> > self-launchers means problems would be less likely than in airplanes.
> > The Earth-X batteries all have a BMS, seem better characterized, and I
> > would trust them a lot more.
> >
>
> Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
> redundant BMS boards to make you feel good. Here's a greatpicture of one:
>
> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/
>
> If you poke around, there's a nice video from the Director of
> Engineering at EarthX, he talks about the requirement to have a
> gas-tight battery box vented to the outside, to use only a three-phase
> alternator to charge it, and to add a crowbar circuit to prevent
> over-voltage. Wonder how many glider pilots go to all this trouble?
>
> I think I'll stick to SLA, just press the button and the engine starts
> in about a second.
>
>
> -Dave
>
> P.S. That StewartB in the original thread was a real hoot. Said he
> worried more about getting mad cow disease than having trouble with his
> EarthX battery. Until his battery went bad. Don't know if he still
> eats hamburgers or not.

Dave,

Perhaps you could post a link to this video - I could not find it. To the contrary, the video I could find extolled the safety of their batteries in aircraft:
https://earthxbatteries.com/product-category/experimental-aircraft

[kinsell]

On 3/22/19 8:23 PM, 2G wrote:
> On Tuesday, March 19, 2019 at 10:04:00 PM UTC-7, kinsell wrote:
>> On 3/17/19 9:54 PM, Eric Greenwell wrote:
>>> kinsell wrote on 3/16/2019 9:46 PM:
>>>
>>>>>
>>>>> Many of us are flying with multi-cell LiFePO4 batteries that have
>>>>> internal wiring and are not filled with resin.Â* Is that a problem?
>>>>> Or is the location of the batteries in this specific glider such that
>>>>> the resin is advisable?Â* A battery fire anywhere in a glider (even
>>>>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
>>>>> fires with this type of battery.Â* It's the lithium-polymer battery
>>>>> pack (also much larger, with many more cells) in the FES systems that
>>>>> has had fires.
>>>>>
>>>>
>>>> Well, the service bulletin talks about an LFP that burned.Â* There was
>>>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
>>>> video of an LFP burning:
>>>>
>>>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
>>>>
>>>>
>>>> There have been claims that LFP's don't burn, but that's simply not true.
>>>
>>> The Aerovoltz battery that burned did not have a BMS; in fact, none of
>>> the Aerovoltz batteries have a BMS (battery management system). I would
>>> not want to use one, even though the short engine runs typical of
>>> self-launchers means problems would be less likely than in airplanes.
>>> The Earth-X batteries all have a BMS, seem better characterized, and I
>>> would trust them a lot more.
>>>
>>
>> Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
>> redundant BMS boards to make you feel good. Here's a greatpicture of one:
>>
>> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/
>>
>> If you poke around, there's a nice video from the Director of
>> Engineering at EarthX, he talks about the requirement to have a
>> gas-tight battery box vented to the outside, to use only a three-phase
>> alternator to charge it, and to add a crowbar circuit to prevent
>> over-voltage. Wonder how many glider pilots go to all this trouble?
>>
>> I think I'll stick to SLA, just press the button and the engine starts
>> in about a second.
>>
>>
>> -Dave
>>
>> P.S. That StewartB in the original thread was a real hoot. Said he
>> worried more about getting mad cow disease than having trouble with his
>> EarthX battery. Until his battery went bad. Don't know if he still
>> eats hamburgers or not.
>
> Dave,
>
> Perhaps you could post a link to this video - I could not find it. To the contrary, the video I could find extolled the safety of their batteries in aircraft:
> https://earthxbatteries.com/product-category/experimental-aircraft
>

That video was in an EAA seminar:

http://go.eaa.org/UVqR00U0BE0SOs03oK000hV


Some good info on charging systems here:

https://earthxbatteries.com/engine-charging-systems-use-lithium-batteries

[2G]

On Friday, March 22, 2019 at 9:23:17 PM UTC-7, kinsell wrote:
> On 3/22/19 8:23 PM, 2G wrote:
> > On Tuesday, March 19, 2019 at 10:04:00 PM UTC-7, kinsell wrote:
> >> On 3/17/19 9:54 PM, Eric Greenwell wrote:
> >>> kinsell wrote on 3/16/2019 9:46 PM:
> >>>
> >>>>>
> >>>>> Many of us are flying with multi-cell LiFePO4 batteries that have
> >>>>> internal wiring and are not filled with resin.Â* Is that a problem?
> >>>>> Or is the location of the batteries in this specific glider such that
> >>>>> the resin is advisable?Â* A battery fire anywhere in a glider (even
> >>>>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
> >>>>> fires with this type of battery.Â* It's the lithium-polymer battery
> >>>>> pack (also much larger, with many more cells) in the FES systems that
> >>>>> has had fires.
> >>>>>
> >>>>
> >>>> Well, the service bulletin talks about an LFP that burned.Â* There was
> >>>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
> >>>> video of an LFP burning:
> >>>>
> >>>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
> >>>>
> >>>>
> >>>> There have been claims that LFP's don't burn, but that's simply not true.
> >>>
> >>> The Aerovoltz battery that burned did not have a BMS; in fact, none of
> >>> the Aerovoltz batteries have a BMS (battery management system). I would
> >>> not want to use one, even though the short engine runs typical of
> >>> self-launchers means problems would be less likely than in airplanes.
> >>> The Earth-X batteries all have a BMS, seem better characterized, and I
> >>> would trust them a lot more.
> >>>
> >>
> >> Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
> >> redundant BMS boards to make you feel good. Here's a greatpicture of one:
> >>
> >> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/
> >>
> >> If you poke around, there's a nice video from the Director of
> >> Engineering at EarthX, he talks about the requirement to have a
> >> gas-tight battery box vented to the outside, to use only a three-phase
> >> alternator to charge it, and to add a crowbar circuit to prevent
> >> over-voltage. Wonder how many glider pilots go to all this trouble?
> >>
> >> I think I'll stick to SLA, just press the button and the engine starts
> >> in about a second.
> >>
> >>
> >> -Dave
> >>
> >> P.S. That StewartB in the original thread was a real hoot. Said he
> >> worried more about getting mad cow disease than having trouble with his
> >> EarthX battery. Until his battery went bad. Don't know if he still
> >> eats hamburgers or not.
> >
> > Dave,
> >
> > Perhaps you could post a link to this video - I could not find it. To the contrary, the video I could find extolled the safety of their batteries in aircraft:
> > https://earthxbatteries.com/product-category/experimental-aircraft
> >
>
> That video was in an EAA seminar:
>
> http://go.eaa.org/UVqR00U0BE0SOs03oK000hV
>
>
> Some good info on charging systems here:
>
> https://earthxbatteries.com/engine-charging-systems-use-lithium-batteries

I am confused, is EarthX saying you have to enclose your lithium battery in a sealed box or not? If so, then why don't they say so on their website?

[[email protected]]

On Saturday, March 23, 2019 at 12:23:17 AM UTC-4, kinsell wrote:
> On 3/22/19 8:23 PM, 2G wrote:
> > On Tuesday, March 19, 2019 at 10:04:00 PM UTC-7, kinsell wrote:
> >> On 3/17/19 9:54 PM, Eric Greenwell wrote:
> >>> kinsell wrote on 3/16/2019 9:46 PM:
> >>>
> >>>>>
> >>>>> Many of us are flying with multi-cell LiFePO4 batteries that have
> >>>>> internal wiring and are not filled with resin.Â* Is that a problem?
> >>>>> Or is the location of the batteries in this specific glider such that
> >>>>> the resin is advisable?Â* A battery fire anywhere in a glider (even
> >>>>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
> >>>>> fires with this type of battery.Â* It's the lithium-polymer battery
> >>>>> pack (also much larger, with many more cells) in the FES systems that
> >>>>> has had fires.
> >>>>>
> >>>>
> >>>> Well, the service bulletin talks about an LFP that burned.Â* There was
> >>>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
> >>>> video of an LFP burning:
> >>>>
> >>>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
> >>>>
> >>>>
> >>>> There have been claims that LFP's don't burn, but that's simply not true.
> >>>
> >>> The Aerovoltz battery that burned did not have a BMS; in fact, none of
> >>> the Aerovoltz batteries have a BMS (battery management system). I would
> >>> not want to use one, even though the short engine runs typical of
> >>> self-launchers means problems would be less likely than in airplanes.
> >>> The Earth-X batteries all have a BMS, seem better characterized, and I
> >>> would trust them a lot more.
> >>>
> >>
> >> Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
> >> redundant BMS boards to make you feel good. Here's a greatpicture of one:
> >>
> >> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/
> >>
> >> If you poke around, there's a nice video from the Director of
> >> Engineering at EarthX, he talks about the requirement to have a
> >> gas-tight battery box vented to the outside, to use only a three-phase
> >> alternator to charge it, and to add a crowbar circuit to prevent
> >> over-voltage. Wonder how many glider pilots go to all this trouble?
> >>
> >> I think I'll stick to SLA, just press the button and the engine starts
> >> in about a second.
> >>
> >>
> >> -Dave
> >>
> >> P.S. That StewartB in the original thread was a real hoot. Said he
> >> worried more about getting mad cow disease than having trouble with his
> >> EarthX battery. Until his battery went bad. Don't know if he still
> >> eats hamburgers or not.
> >
> > Dave,
> >
> > Perhaps you could post a link to this video - I could not find it. To the contrary, the video I could find extolled the safety of their batteries in aircraft:
> > https://earthxbatteries.com/product-category/experimental-aircraft
> >
>
> That video was in an EAA seminar:
>
> http://go.eaa.org/UVqR00U0BE0SOs03oK000hV
>
>
> Some good info on charging systems here:
>
> https://earthxbatteries.com/engine-charging-systems-use-lithium-batteries

I'm not convinced that earthx page offers "good info". There are many obviously false statements. E.g., oxidation actually uses up oxygen, rather than create free oxygen. And generator coils do not always put out the same amount of power at a given RPM - disconnect the output and the power will be zero. Most importantly for our discussion here, their claims about what causes overheating of the battery during charging are not convincing, and I'd look for evidence elsewhere.

[kinsell]

On 3/22/19 11:23 PM, 2G wrote:
> On Friday, March 22, 2019 at 9:23:17 PM UTC-7, kinsell wrote:
>> On 3/22/19 8:23 PM, 2G wrote:
>>> On Tuesday, March 19, 2019 at 10:04:00 PM UTC-7, kinsell wrote:
>>>> On 3/17/19 9:54 PM, Eric Greenwell wrote:
>>>>> kinsell wrote on 3/16/2019 9:46 PM:
>>>>>
>>>>>>>
>>>>>>> Many of us are flying with multi-cell LiFePO4 batteries that have
>>>>>>> internal wiring and are not filled with resin.Â* Is that a problem?
>>>>>>> Or is the location of the batteries in this specific glider such that
>>>>>>> the resin is advisable?Â* A battery fire anywhere in a glider (even
>>>>>>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
>>>>>>> fires with this type of battery.Â* It's the lithium-polymer battery
>>>>>>> pack (also much larger, with many more cells) in the FES systems that
>>>>>>> has had fires.
>>>>>>>
>>>>>>
>>>>>> Well, the service bulletin talks about an LFP that burned.Â* There was
>>>>>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
>>>>>> video of an LFP burning:
>>>>>>
>>>>>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
>>>>>>
>>>>>>
>>>>>> There have been claims that LFP's don't burn, but that's simply not true.
>>>>>
>>>>> The Aerovoltz battery that burned did not have a BMS; in fact, none of
>>>>> the Aerovoltz batteries have a BMS (battery management system). I would
>>>>> not want to use one, even though the short engine runs typical of
>>>>> self-launchers means problems would be less likely than in airplanes.
>>>>> The Earth-X batteries all have a BMS, seem better characterized, and I
>>>>> would trust them a lot more.
>>>>>
>>>>
>>>> Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
>>>> redundant BMS boards to make you feel good. Here's a greatpicture of one:
>>>>
>>>> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/
>>>>
>>>> If you poke around, there's a nice video from the Director of
>>>> Engineering at EarthX, he talks about the requirement to have a
>>>> gas-tight battery box vented to the outside, to use only a three-phase
>>>> alternator to charge it, and to add a crowbar circuit to prevent
>>>> over-voltage. Wonder how many glider pilots go to all this trouble?
>>>>
>>>> I think I'll stick to SLA, just press the button and the engine starts
>>>> in about a second.
>>>>
>>>>
>>>> -Dave
>>>>
>>>> P.S. That StewartB in the original thread was a real hoot. Said he
>>>> worried more about getting mad cow disease than having trouble with his
>>>> EarthX battery. Until his battery went bad. Don't know if he still
>>>> eats hamburgers or not.
>>>
>>> Dave,
>>>
>>> Perhaps you could post a link to this video - I could not find it. To the contrary, the video I could find extolled the safety of their batteries in aircraft:
>>> https://earthxbatteries.com/product-category/experimental-aircraft
>>>
>>
>> That video was in an EAA seminar:
>>
>> http://go.eaa.org/UVqR00U0BE0SOs03oK000hV
>>
>>
>> Some good info on charging systems here:
>>
>> https://earthxbatteries.com/engine-charging-systems-use-lithium-batteries
>
> I am confused, is EarthX saying you have to enclose your lithium battery in a sealed box or not? If so, then why don't they say so on their website?
>

Websites are intended to sell product. You put too much truth on them,
they become less effective. It's like the Aerovoltz guy admitting that
the products are "smokebombs", you're not going to find that on the website.

[kinsell]

On 3/19/19 3:27 PM, SF wrote:
> I cut one of my K2 batteries open, after one of the cells in it failed. There's not a lot of space available in there for foam, or drill bits.
>
> -nick one of the cells with a drill and it's going to be bad.
> -Equal foam filling is unlikely
> -Good possibility of the foam compressing the cells or expanding the case.
> -The foam is going to interfere with heat dissipation in a big way, its a pretty good insulator.
> -When chasing vibration issues, sometimes tightening up the system makes things worse not better.

I would agree with the above. The fix is likely to make things worse
rather than better.


> -No one ever said they wouldn't catch on fire.

You're kidding, right?


>Just if they do, they can be put out by depriving them of oxygen. Unlike Lithium ion chemistry batteries which supply their own oxidizer if they catch on fire. So the LiFePO batteries are considered to be a safer battery chemistry, but not a completely safe battery.

Safer than what?


> A plastic box full of lead plates submerged in sulfuric acid isn't completely safe either.

Nothing is entirely safe. But the safety record of SLA batteries in
gliders over the past 25 years or so is outstanding. I assume you're
confusing wet cell batteries with SLA?

>
> A LiFePO battery(s) with an internal BMS board, with a fuse right at the battery is the way to go, but treat it with the respect that that much energy stored in a small package deserves.
>

But of course that doesn't solve the problem brought up in the tech
note. If you have batteries that short out internally in normal use,
then discarding them is the only proper way to go.


> SF
>

-Dave

[Eric Greenwell[_4_]]

2G wrote on 3/22/2019 10:23 PM:
>> That video was in an EAA seminar:
>>
>> http://go.eaa.org/UVqR00U0BE0SOs03oK000hV
>>
>>
>> Some good info on charging systems here:
>>
>> https://earthxbatteries.com/engine-charging-systems-use-lithium-batteries
>
> I am confused, is EarthX saying you have to enclose your lithium battery in a sealed box or not? If so, then why don't they say so on their website?

EarthX says:

4- Only the ETX900-VNT is designed for in cabin installations as it has a venting
system build in and is also in a fire proof containment system.

https://earthxbatteries.com/product-category/experimental-aircraft

Scroll down and select "Important safety/use precautions"


--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorgliders/publications/download-the-guide-1
- "Transponders in Sailplanes - Dec 2014a" also ADS-B, PCAS, Flarm

http://soaringsafety.org/prevention/Guide-to-transponders-in-sailplanes-2014A.pdf

[2G]

On Saturday, March 23, 2019 at 7:42:49 AM UTC-7, kinsell wrote:
> On 3/22/19 11:23 PM, 2G wrote:
> > On Friday, March 22, 2019 at 9:23:17 PM UTC-7, kinsell wrote:
> >> On 3/22/19 8:23 PM, 2G wrote:
> >>> On Tuesday, March 19, 2019 at 10:04:00 PM UTC-7, kinsell wrote:
> >>>> On 3/17/19 9:54 PM, Eric Greenwell wrote:
> >>>>> kinsell wrote on 3/16/2019 9:46 PM:
> >>>>>
> >>>>>>>
> >>>>>>> Many of us are flying with multi-cell LiFePO4 batteries that have
> >>>>>>> internal wiring and are not filled with resin.Â* Is that a problem?
> >>>>>>> Or is the location of the batteries in this specific glider such that
> >>>>>>> the resin is advisable?Â* A battery fire anywhere in a glider (even
> >>>>>>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
> >>>>>>> fires with this type of battery.Â* It's the lithium-polymer battery
> >>>>>>> pack (also much larger, with many more cells) in the FES systems that
> >>>>>>> has had fires.
> >>>>>>>
> >>>>>>
> >>>>>> Well, the service bulletin talks about an LFP that burned.Â* There was
> >>>>>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
> >>>>>> video of an LFP burning:
> >>>>>>
> >>>>>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
> >>>>>>
> >>>>>>
> >>>>>> There have been claims that LFP's don't burn, but that's simply not true.
> >>>>>
> >>>>> The Aerovoltz battery that burned did not have a BMS; in fact, none of
> >>>>> the Aerovoltz batteries have a BMS (battery management system). I would
> >>>>> not want to use one, even though the short engine runs typical of
> >>>>> self-launchers means problems would be less likely than in airplanes.
> >>>>> The Earth-X batteries all have a BMS, seem better characterized, and I
> >>>>> would trust them a lot more.
> >>>>>
> >>>>
> >>>> Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
> >>>> redundant BMS boards to make you feel good. Here's a greatpicture of one:
> >>>>
> >>>> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/
> >>>>
> >>>> If you poke around, there's a nice video from the Director of
> >>>> Engineering at EarthX, he talks about the requirement to have a
> >>>> gas-tight battery box vented to the outside, to use only a three-phase
> >>>> alternator to charge it, and to add a crowbar circuit to prevent
> >>>> over-voltage. Wonder how many glider pilots go to all this trouble?
> >>>>
> >>>> I think I'll stick to SLA, just press the button and the engine starts
> >>>> in about a second.
> >>>>
> >>>>
> >>>> -Dave
> >>>>
> >>>> P.S. That StewartB in the original thread was a real hoot. Said he
> >>>> worried more about getting mad cow disease than having trouble with his
> >>>> EarthX battery. Until his battery went bad. Don't know if he still
> >>>> eats hamburgers or not.
> >>>
> >>> Dave,
> >>>
> >>> Perhaps you could post a link to this video - I could not find it. To the contrary, the video I could find extolled the safety of their batteries in aircraft:
> >>> https://earthxbatteries.com/product-category/experimental-aircraft
> >>>
> >>
> >> That video was in an EAA seminar:
> >>
> >> http://go.eaa.org/UVqR00U0BE0SOs03oK000hV
> >>
> >>
> >> Some good info on charging systems here:
> >>
> >> https://earthxbatteries.com/engine-charging-systems-use-lithium-batteries
> >
> > I am confused, is EarthX saying you have to enclose your lithium battery in a sealed box or not? If so, then why don't they say so on their website?
> >
>
> Websites are intended to sell product. You put too much truth on them,
> they become less effective. It's like the Aerovoltz guy admitting that
> the products are "smokebombs", you're not going to find that on the website.

Dave,

Did you actually watch this video? I ask because your link was a registration by someone else to the webinar, and doesn't work even if you put in your own email. I did find the webinar here:
https://video.eaa.org/detail/video/5456130349001/webinar--lithium-batteries-explained?autoStart=true&q=Lithium%20Batteries%20Explained
I watched the whole thing and didn't find reference to a gas-tight box with venting. He did say that EarthX has done a lot of testing of their lithium batteries and haven't seen one go into thermal runaway. He also said that thermal runaway occurs at temperatures starting at 270 C, the highest of all lithium chemistry's.

You wrote:
"Dual
redundant BMS boards to make you feel good. Here's a greatpicture of one:

http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/ "

If you had gone to the next page, you would have learned that the battery pictured is an ETX12A, which DOES NOT have a BMS. Furthermore, it was used on an engine w/o a starter, contrary to the direct warnings by EarthX:
http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/&page=2
In other words, this incident has absolutely nothing to do with our application.

Finally, you say I put "too much truth" on company websites. I have said this before: I DO NOT vouch for the accuracy of any company's literature or video, whether it is printed or online; I merely make reference to it so you can make your own decision. But, if you do not believe what they are presenting, DO NOT USE THEIR PRODUCTS!

[kinsell]

On 3/24/19 9:52 AM, 2G wrote:
> On Saturday, March 23, 2019 at 7:42:49 AM UTC-7, kinsell wrote:
>> On 3/22/19 11:23 PM, 2G wrote:
>>> On Friday, March 22, 2019 at 9:23:17 PM UTC-7, kinsell wrote:
>>>> On 3/22/19 8:23 PM, 2G wrote:
>>>>> On Tuesday, March 19, 2019 at 10:04:00 PM UTC-7, kinsell wrote:
>>>>>> On 3/17/19 9:54 PM, Eric Greenwell wrote:
>>>>>>> kinsell wrote on 3/16/2019 9:46 PM:
>>>>>>>
>>>>>>>>>
>>>>>>>>> Many of us are flying with multi-cell LiFePO4 batteries that have
>>>>>>>>> internal wiring and are not filled with resin.Â* Is that a problem?
>>>>>>>>> Or is the location of the batteries in this specific glider such that
>>>>>>>>> the resin is advisable?Â* A battery fire anywhere in a glider (even
>>>>>>>>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
>>>>>>>>> fires with this type of battery.Â* It's the lithium-polymer battery
>>>>>>>>> pack (also much larger, with many more cells) in the FES systems that
>>>>>>>>> has had fires.
>>>>>>>>>
>>>>>>>>
>>>>>>>> Well, the service bulletin talks about an LFP that burned.Â* There was
>>>>>>>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
>>>>>>>> video of an LFP burning:
>>>>>>>>
>>>>>>>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
>>>>>>>>
>>>>>>>>
>>>>>>>> There have been claims that LFP's don't burn, but that's simply not true.
>>>>>>>
>>>>>>> The Aerovoltz battery that burned did not have a BMS; in fact, none of
>>>>>>> the Aerovoltz batteries have a BMS (battery management system). I would
>>>>>>> not want to use one, even though the short engine runs typical of
>>>>>>> self-launchers means problems would be less likely than in airplanes.
>>>>>>> The Earth-X batteries all have a BMS, seem better characterized, and I
>>>>>>> would trust them a lot more.
>>>>>>>
>>>>>>
>>>>>> Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
>>>>>> redundant BMS boards to make you feel good. Here's a greatpicture of one:
>>>>>>
>>>>>> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/
>>>>>>
>>>>>> If you poke around, there's a nice video from the Director of
>>>>>> Engineering at EarthX, he talks about the requirement to have a
>>>>>> gas-tight battery box vented to the outside, to use only a three-phase
>>>>>> alternator to charge it, and to add a crowbar circuit to prevent
>>>>>> over-voltage. Wonder how many glider pilots go to all this trouble?
>>>>>>
>>>>>> I think I'll stick to SLA, just press the button and the engine starts
>>>>>> in about a second.
>>>>>>
>>>>>>
>>>>>> -Dave
>>>>>>
>>>>>> P.S. That StewartB in the original thread was a real hoot. Said he
>>>>>> worried more about getting mad cow disease than having trouble with his
>>>>>> EarthX battery. Until his battery went bad. Don't know if he still
>>>>>> eats hamburgers or not.
>>>>>
>>>>> Dave,
>>>>>
>>>>> Perhaps you could post a link to this video - I could not find it. To the contrary, the video I could find extolled the safety of their batteries in aircraft:
>>>>> https://earthxbatteries.com/product-category/experimental-aircraft
>>>>>
>>>>
>>>> That video was in an EAA seminar:
>>>>
>>>> http://go.eaa.org/UVqR00U0BE0SOs03oK000hV
>>>>
>>>>
>>>> Some good info on charging systems here:
>>>>
>>>> https://earthxbatteries.com/engine-charging-systems-use-lithium-batteries
>>>
>>> I am confused, is EarthX saying you have to enclose your lithium battery in a sealed box or not? If so, then why don't they say so on their website?
>>>
>>
>> Websites are intended to sell product. You put too much truth on them,
>> they become less effective. It's like the Aerovoltz guy admitting that
>> the products are "smokebombs", you're not going to find that on the website.
>
> Dave,
>
> Did you actually watch this video? I ask because your link was a registration by someone else to the webinar, and doesn't work even if you put in your own email. I did find the webinar here:
> https://video.eaa.org/detail/video/5456130349001/webinar--lithium-batteries-explained?autoStart=true&q=Lithium%20Batteries%20Explained

I watched it a long time ago. At that point, the link worked as
expected. Perhaps they edited the video, don't know. Doesn't matter,
the link Eric just posted makes it clear that for inside cabin mounting,
only the ETX900-VNT is to be used since it has a fire-proof casing which
also is a venting system. The manual goes into detail about venting to
the outside.




>
> You wrote:
> "Dual
> redundant BMS boards to make you feel good. Here's a greatpicture of one:
>
> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/ "
>
> If you had gone to the next page, you would have learned that the battery pictured is an ETX12A, which DOES NOT have a BMS. Furthermore, it was used on an engine w/o a starter, contrary to the direct warnings by EarthX:

Yet at 24 minutes into your video, he's saying that all EarthX batteries
have BMS. And other users are saying the claims about an oversized
alternator are bogus.


>
> Finally, you say I put "too much truth" on company websites. I have said this before: I DO NOT vouch for the accuracy of any company's literature or video, whether it is printed or online; I merely make reference to it so you can make your own decision. But, if you do not believe what they are presenting, DO NOT USE THEIR PRODUCTS!
>

I wasn't saying that you personally were responsible for their website.
I was saying "if someone put too much truth", just referencing the fact
that websites tend to gloss over negatives, and overplay the positives.

One thing in the seminar that didn't make it into the important safety
precautions list was wiring up the warning system to a light, or into an
EFIS on the panel. The presenter considered that to be mandatory, but
you have to dig into the manual to find it on the website.

-Dave

[2G]

On Sunday, March 24, 2019 at 4:43:31 PM UTC-7, kinsell wrote:
> On 3/24/19 9:52 AM, 2G wrote:
> > On Saturday, March 23, 2019 at 7:42:49 AM UTC-7, kinsell wrote:
> >> On 3/22/19 11:23 PM, 2G wrote:
> >>> On Friday, March 22, 2019 at 9:23:17 PM UTC-7, kinsell wrote:
> >>>> On 3/22/19 8:23 PM, 2G wrote:
> >>>>> On Tuesday, March 19, 2019 at 10:04:00 PM UTC-7, kinsell wrote:
> >>>>>> On 3/17/19 9:54 PM, Eric Greenwell wrote:
> >>>>>>> kinsell wrote on 3/16/2019 9:46 PM:
> >>>>>>>
> >>>>>>>>>
> >>>>>>>>> Many of us are flying with multi-cell LiFePO4 batteries that have
> >>>>>>>>> internal wiring and are not filled with resin.Â* Is that a problem?
> >>>>>>>>> Or is the location of the batteries in this specific glider such that
> >>>>>>>>> the resin is advisable?Â* A battery fire anywhere in a glider (even
> >>>>>>>>> without a fuel tank) is catastrophic. OTOH I havn't heard of any
> >>>>>>>>> fires with this type of battery.Â* It's the lithium-polymer battery
> >>>>>>>>> pack (also much larger, with many more cells) in the FES systems that
> >>>>>>>>> has had fires.
> >>>>>>>>>
> >>>>>>>>
> >>>>>>>> Well, the service bulletin talks about an LFP that burned.Â* There was
> >>>>>>>> a fire in an EB-28 in Finland last year with a 10 A-H LFP.Â* Here's a
> >>>>>>>> video of an LFP burning:
> >>>>>>>>
> >>>>>>>> https://www.pilotsofamerica.com/community/threads/aircraft-lithium-battery-fires.102016/
> >>>>>>>>
> >>>>>>>>
> >>>>>>>> There have been claims that LFP's don't burn, but that's simply not true.
> >>>>>>>
> >>>>>>> The Aerovoltz battery that burned did not have a BMS; in fact, none of
> >>>>>>> the Aerovoltz batteries have a BMS (battery management system). I would
> >>>>>>> not want to use one, even though the short engine runs typical of
> >>>>>>> self-launchers means problems would be less likely than in airplanes.
> >>>>>>> The Earth-X batteries all have a BMS, seem better characterized, and I
> >>>>>>> would trust them a lot more.
> >>>>>>>
> >>>>>>
> >>>>>> Yes, EarthX is well regarded in the homebuilt powerplane world. Dual
> >>>>>> redundant BMS boards to make you feel good. Here's a greatpicture of one:
> >>>>>>
> >>>>>> http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/
> >>>>>>
> >>>>>> If you poke around, there's a nice video from the Director of
> >>>>>> Engineering at EarthX, he talks about the requirement to have a
> >>>>>> gas-tight battery box vented to the outside, to use only a three-phase
> >>>>>> alternator to charge it, and to add a crowbar circuit to prevent
> >>>>>> over-voltage. Wonder how many glider pilots go to all this trouble?
> >>>>>>
> >>>>>> I think I'll stick to SLA, just press the button and the engine starts
> >>>>>> in about a second.
> >>>>>>
> >>>>>>
> >>>>>> -Dave
> >>>>>>
> >>>>>> P.S. That StewartB in the original thread was a real hoot. Said he
> >>>>>> worried more about getting mad cow disease than having trouble with his
> >>>>>> EarthX battery. Until his battery went bad. Don't know if he still
> >>>>>> eats hamburgers or not.
> >>>>>
> >>>>> Dave,
> >>>>>
> >>>>> Perhaps you could post a link to this video - I could not find it. To the contrary, the video I could find extolled the safety of their batteries in aircraft:
> >>>>> https://earthxbatteries.com/product-category/experimental-aircraft
> >>>>>
> >>>>
> >>>> That video was in an EAA seminar:
> >>>>
> >>>> http://go.eaa.org/UVqR00U0BE0SOs03oK000hV
> >>>>
> >>>>
> >>>> Some good info on charging systems here:
> >>>>
> >>>> https://earthxbatteries.com/engine-charging-systems-use-lithium-batteries
> >>>
> >>> I am confused, is EarthX saying you have to enclose your lithium battery in a sealed box or not? If so, then why don't they say so on their website?
> >>>
> >>
> >> Websites are intended to sell product. You put too much truth on them,
> >> they become less effective. It's like the Aerovoltz guy admitting that
> >> the products are "smokebombs", you're not going to find that on the website.
> >
> > Dave,
> >
> > Did you actually watch this video? I ask because your link was a registration by someone else to the webinar, and doesn't work even if you put in your own email. I did find the webinar here:
> > https://video.eaa.org/detail/video/5456130349001/webinar--lithium-batteries-explained?autoStart=true&q=Lithium%20Batteries%20Explained
>
> I watched it a long time ago. At that point, the link worked as
> expected. Perhaps they edited the video, don't know. Doesn't matter,
> the link Eric just posted makes it clear that for inside cabin mounting,
> only the ETX900-VNT is to be used since it has a fire-proof casing which
> also is a venting system. The manual goes into detail about venting to
> the outside.

That might be a good idea for any starter battery, space permitting. I believe that a LFP battery with a BMS is a safer battery than a PB because the BMS will current limit whereas the PB will not unless fused. High currents will cause the wire insulation to melt and generate fumes, unless your glider is wired with aviation-grade wire (most aren't). A non-starter battery such as the Bioenno, shouldn't be any problem at all.
>
>
>
>
> >
> > You wrote:
> > "Dual
> > redundant BMS boards to make you feel good. Here's a greatpicture of one:
> >
> > http://www.avidfoxflyers.com/index.php?/topic/2963-earth-x-battery-warning/ "
> >
> > If you had gone to the next page, you would have learned that the battery pictured is an ETX12A, which DOES NOT have a BMS. Furthermore, it was used on an engine w/o a starter, contrary to the direct warnings by EarthX:
>
> Yet at 24 minutes into your video, he's saying that all EarthX batteries
> have BMS. And other users are saying the claims about an oversized
> alternator are bogus.

EarthX clearly stated that the use of the ETX12A was an improper use, and that only the hundred series are approved for experimental aircraft. Which "other users" are you talking about? EarthX is VERY CLEAR that vintage alternators are not to be used for charging their batteries and use in these aircraft are not recommended.

>
>
> >
> > Finally, you say I put "too much truth" on company websites. I have said this before: I DO NOT vouch for the accuracy of any company's literature or video, whether it is printed or online; I merely make reference to it so you can make your own decision. But, if you do not believe what they are presenting, DO NOT USE THEIR PRODUCTS!
> >
>
> I wasn't saying that you personally were responsible for their website.
> I was saying "if someone put too much truth", just referencing the fact
> that websites tend to gloss over negatives, and overplay the positives.

To the contrary, EarthX is very explicit about misuses of their batteries that you seem to want to disregard.

>
> One thing in the seminar that didn't make it into the important safety
> precautions list was wiring up the warning system to a light, or into an
> EFIS on the panel. The presenter considered that to be mandatory, but
> you have to dig into the manual to find it on the website.

The warning light was not listed as being mandatory, but presented as an additional safety feature. I have never seen this on any other battery, so I regard it as innovative on their part.

The testing I have done recently on a Bioenno battery vs a PC680 is that the Bioenno has about 40% more energy (WH, not AH) new. This advantage will increase with age as the LFP battery after 4-5 years should still be at 95%, while the PB battery will be down anywhere from 25% to 50%, or more. I will continue to use a PB for engine starting as that is compatible with the voltage regulator, and starter batteries last much longer than the instrument battery.

Tom