Battery 6ah vs. more

[Roy Clark, \B6\]

Time to repace my 12v 6ah SLA battery. Same or 7ah or 8ah?

[Kevin Anderson]

I have been using the Power Sonic Fast Discharge rate battery PSH-12100F2,
10.5 amp hr, in the same size case as their 7 ah for the past 3 years.

It has held up quite well, and even have a couple of 10 hour wave flights on
just one battery (I am set up with two) running a PDA, Vario, Radio.

Kevin
SGS 1-26B 192

"Roy Clark, "B6"" > wrote in message
...
> Time to repace my 12v 6ah SLA battery. Same or 7ah or 8ah?

[Roy Clark, \B6\]

On Apr 20, 7:56*am, "Kevin Anderson" >
wrote:
> I have been using the Power Sonic Fast Discharge rate battery PSH-12100F2,
> 10.5 amp hr, in the same size case as their 7 ah for the past 3 years.
>
> It has held up quite well, and even have a couple of 10 hour wave flights on
> just one battery (I am set up with two) *running a PDA, Vario, Radio.
>
> Kevin
> SGS 1-26B 192

Thanks, but fly with 2 systems - one for transponder only - and the
battery you
suggest won't fit.

Anyone elss have a suggestion.

[[email protected]]

On Apr 21, 6:55*am, "Roy Clark, \"B6\"" > wrote:
> On Apr 20, 7:56*am, "Kevin *Anderson" >
> wrote:
>
> > I have been using the Power Sonic Fast Discharge rate battery PSH-12100F2,
> > 10.5 amp hr, in the same size case as their 7 ah for the past 3 years.
>
> > It has held up quite well, and even have a couple of 10 hour wave flights on
> > just one battery (I am set up with two) *running a PDA, Vario, Radio.
>
> > Kevin
> > SGS 1-26B 192
>
> Thanks, but fly with 2 systems - one for transponder only - and the
> battery you
> suggest won't fit.
>
> Anyone elss have a suggestion.

Roy,
To have a valid suggestion, people need to know what equipment
you're running and the total current draw (on each batter circuit if
two systems).
I have a 10Ah battery (single) powering nothing but a radio and
vario. Flew 6 days at Tonopah (avg flight 4 hours) and two more
weekends before my volt meter finally said I was in need of a
recharge.
I have since added a Cambridge 302A CFR and an iPAQ, and should
still be good for 15 hours of system 'on' time.
Bottom line, if the 6 Ah battery was sufficient, why change?

[Discus 44]

On Apr 20, 7:18*am, "Roy Clark, \"B6\"" > wrote:
> Time to repace my 12v 6ah SLA battery. Same or 7ah or 8ah?

Roy:

What 6 aH battery are you replacing? Most of my battery information
does not show a 6 aH type. They do show a 5.4 then a 7 aH and a 8 aH
with the same dimensions as a 7 aH. Here are the links:
http://www.panasonic.com/industrial/battery/oem/chem/seal/index.html
http://www.power-sonic.com/index.php?id=29
consider a 7 aH If the ship allows for it. They are usually available
for a lower price. I know of several sources locally.

T. Udd

[[email protected]]

On Apr 21, 10:18*am, wrote:
> On Apr 21, 6:55*am, "Roy Clark, \"B6\"" > wrote:
>
>
>
>
>
> > On Apr 20, 7:56*am, "Kevin *Anderson" >
> > wrote:
>
> > > I have been using the Power Sonic Fast Discharge rate battery PSH-12100F2,
> > > 10.5 amp hr, in the same size case as their 7 ah for the past 3 years.
>
> > > It has held up quite well, and even have a couple of 10 hour wave flights on
> > > just one battery (I am set up with two) *running a PDA, Vario, Radio..
>
> > > Kevin
> > > SGS 1-26B 192
>
> > Thanks, but fly with 2 systems - one for transponder only - and the
> > battery you
> > suggest won't fit.
>
> > Anyone elss have a suggestion.
>
> Roy,
> * To have a valid suggestion, people need to know what equipment
> you're running and the total current draw (on each batter circuit if
> two systems).
> * I have a 10Ah battery (single) powering nothing but a radio and
> vario. *Flew 6 days at Tonopah (avg flight 4 hours) and two more
> weekends before my volt meter finally said I was in need of a
> recharge.
> * I have since added a Cambridge 302A CFR and an iPAQ, and should
> still be good for 15 hours of system 'on' time.
> * Bottom line, if the 6 Ah battery was sufficient, why change?- Hide quoted text -
>
> - Show quoted text -

The longer you allow your lead-acid battery to sit at less than full
charge, the shorter it's life will be. Combine that with deep
discharges, and it gets worse. Of course the convenience factor of not
charging for every flight might be worth the cost of replacing more
often. The downside is premature failure when you least expect it.

I alternate two batteries by pulling the one I flew with at the end of
the day and replacing it with a fully charged one that I brought from
home. That way if I don't fly again for a while, the battery in the
ship is fully charged and should last quite a while without worry of
sulfating. This system allows me to always have two charged batteries
on hand at the start of every flying day. It spreads the discharge/
charge cycles over two batteries instead of one and limits deep
discharges as much as possible. If I forget to bring the second
battery along to the field, the one in the ship is charged and ready
for that day anyway.


Dave

[[email protected]]

Buy the biggest you can fit!

Powersonic has a 9 AH in same format as 7.2

Then add more batteries, they are cheap, lost instruments are
dangerous, lost OLC logs are maddening!

From experience.... now running 3 batteries..... saves me adding water
ballast! ;-)

Bob



On Apr 20, 10:18 am, "Roy Clark, \"B6\"" > wrote:
> Time to repace my 12v 6ah SLA battery. Same or 7ah or 8ah?

[kirk.stant]

> Buy the biggest you can fit!
>
> Powersonic has a 9 AH in same format as 7.2
>
> Then add more batteries, they are cheap, lost instruments are
> dangerous, lost OLC logs are maddening!
>
> From experience.... now running 3 batteries..... saves me adding water
> ballast! *;-)
>
> Bob

AMEN!

My solution was to split the cockpit into two electrical busses, each
with it's own 9AH battery. Either side can fail and I have enough
"stuff" to get home (or finish a race...). Can also gang the busses
so either battery can power all the cockpit.

I have 3 batteries, one is always on the charger, and rotate the ones
from the flight every evening - so I always have 2 fully charged
batteries every flight. No special connectors on the batteries, so
any standard size 7 - 9 AH "brick" with spade connectors will fit, if
necessary.

It's worked so far (8 years and counting...).

I see there are some new technology batteries coming on the market for
gliders (in S&G?) - maybe we are about to move on from our beloved
lead bricks!

Kirk
66

[nimbusgb]

On 22 Apr, 14:13, "kirk.stant" > wrote:
> > Buy the biggest you can fit!
>
> > Powersonic has a 9 AH in same format as 7.2
>
> > Then add more batteries, they are cheap, lost instruments are
> > dangerous, lost OLC logs are maddening!
>
> > From experience.... now running 3 batteries..... saves me adding water
> > ballast! ;-)
>
> > Bob
>
> AMEN!
>
> My solution was to split the cockpit into two electrical busses, each
> with it's own 9AH battery. Either side can fail and I have enough
> "stuff" to get home (or finish a race...). Can also gang the busses
> so either battery can power all the cockpit.
>
> I have 3 batteries, one is always on the charger, and rotate the ones
> from the flight every evening - so I always have 2 fully charged
> batteries every flight. No special connectors on the batteries, so
> any standard size 7 - 9 AH "brick" with spade connectors will fit, if
> necessary.
>
> It's worked so far (8 years and counting...).
>
> I see there are some new technology batteries coming on the market for
> gliders (in S&G?) - maybe we are about to move on from our beloved
> lead bricks!
>
> Kirk
> 66

I replaced my lead acid 7 ah brick with a NiMh pack made up by a
supplier. The result is a pack that fits into the same battery holder
slot, is 30% lower in height, 50% lighter, runs at 14v nominal and
has a 9 Ah capacity. It was so succesfull that I replaced the second
15 ah battery used to raise and lower the turbo with a similar pack
but of only 12ah but saving 7kg.

One other advantage is that they use a purpose built microprocessor
controlled charger that ensures they are fully charged and ready to go
even when left permanently connected.

[Herb]

On Apr 23, 1:56 am, nimbusgb > wrote:
> On 22 Apr, 14:13, "kirk.stant" > wrote:
>
>
>
> > > Buy the biggest you can fit!
>
> > > Powersonic has a 9 AH in same format as 7.2
>
> > > Then add more batteries, they are cheap, lost instruments are
> > > dangerous, lost OLC logs are maddening!
>
> > > From experience.... now running 3 batteries..... saves me adding water
> > > ballast! ;-)
>
> > > Bob
>
> > AMEN!
>
> > My solution was to split the cockpit into two electrical busses, each
> > with it's own 9AH battery. Either side can fail and I have enough
> > "stuff" to get home (or finish a race...). Can also gang the busses
> > so either battery can power all the cockpit.
>
> > I have 3 batteries, one is always on the charger, and rotate the ones
> > from the flight every evening - so I always have 2 fully charged
> > batteries every flight. No special connectors on the batteries, so
> > any standard size 7 - 9 AH "brick" with spade connectors will fit, if
> > necessary.
>
> > It's worked so far (8 years and counting...).
>
> > I see there are some new technology batteries coming on the market for
> > gliders (in S&G?) - maybe we are about to move on from our beloved
> > lead bricks!
>
> > Kirk
> > 66
>
> I replaced my lead acid 7 ah brick with a NiMh pack made up by a
> supplier. The result is a pack that fits into the same battery holder
> slot, is 30% lower in height, 50% lighter, runs at 14v nominal and
> has a 9 Ah capacity. It was so succesfull that I replaced the second
> 15 ah battery used to raise and lower the turbo with a similar pack
> but of only 12ah but saving 7kg.
>
> One other advantage is that they use a purpose built microprocessor
> controlled charger that ensures they are fully charged and ready to go
> even when left permanently connected.

Same here, 10Ah NiMh battery dedicated to the transponder, two 5Ah
packs for the instruments (one in the tail). Charger is putting out
2A and takes only about 2-4h after a normal day of flying to replenish
the batteries. I built the packs myself from cells with tabs and paid
only $80 for the large 10Ah pack, half of that for each of the small
ones. No more lead-acid batteries! The weight savings mentioned by
nimbusgb might be a bit aggressive, I'd say NiMh is about 60% lighter
than the same lead-acid capacity battery.
Herb

[Mike the Strike]

On Apr 23, 9:11 am, Herb > wrote:
> On Apr 23, 1:56 am, nimbusgb > wrote:
>
>
>
> > On 22 Apr, 14:13, "kirk.stant" > wrote:
>
> > > > Buy the biggest you can fit!
>
> > > > Powersonic has a 9 AH in same format as 7.2
>
> > > > Then add more batteries, they are cheap, lost instruments are
> > > > dangerous, lost OLC logs are maddening!
>
> > > > From experience.... now running 3 batteries..... saves me adding water
> > > > ballast! ;-)
>
> > > > Bob
>
> > > AMEN!
>
> > > My solution was to split the cockpit into two electrical busses, each
> > > with it's own 9AH battery. Either side can fail and I have enough
> > > "stuff" to get home (or finish a race...). Can also gang the busses
> > > so either battery can power all the cockpit.
>
> > > I have 3 batteries, one is always on the charger, and rotate the ones
> > > from the flight every evening - so I always have 2 fully charged
> > > batteries every flight. No special connectors on the batteries, so
> > > any standard size 7 - 9 AH "brick" with spade connectors will fit, if
> > > necessary.
>
> > > It's worked so far (8 years and counting...).
>
> > > I see there are some new technology batteries coming on the market for
> > > gliders (in S&G?) - maybe we are about to move on from our beloved
> > > lead bricks!
>
> > > Kirk
> > > 66
>
> > I replaced my lead acid 7 ah brick with a NiMh pack made up by a
> > supplier. The result is a pack that fits into the same battery holder
> > slot, is 30% lower in height, 50% lighter, runs at 14v nominal and
> > has a 9 Ah capacity. It was so succesfull that I replaced the second
> > 15 ah battery used to raise and lower the turbo with a similar pack
> > but of only 12ah but saving 7kg.
>
> > One other advantage is that they use a purpose built microprocessor
> > controlled charger that ensures they are fully charged and ready to go
> > even when left permanently connected.
>
> Same here, 10Ah NiMh battery dedicated to the transponder, two 5Ah
> packs for the instruments (one in the tail). Charger is putting out
> 2A and takes only about 2-4h after a normal day of flying to replenish
> the batteries. I built the packs myself from cells with tabs and paid
> only $80 for the large 10Ah pack, half of that for each of the small
> ones. No more lead-acid batteries! The weight savings mentioned by
> nimbusgb might be a bit aggressive, I'd say NiMh is about 60% lighter
> than the same lead-acid capacity battery.
> Herb

I have four batteries and like lead for the extra weight. Higher wing
loading is good out west!

Mike

[ContestID67]

I'd love to see some pictures of your NiMh creations.

Can you send to me or upload somewhere like http://www.flickr.com.

This would also be a great how to article for Soaring.

john <at> derosaweb.com

Thanks

[nimbusgb]

On 23 Apr, 16:11, Herb > wrote:
> On Apr 23, 1:56 am, nimbusgb > wrote:
>
>
>
> > On 22 Apr, 14:13, "kirk.stant" > wrote:
>
> > > > Buy the biggest you can fit!
>
> > > > Powersonic has a 9 AH in same format as 7.2
>
> > > > Then add more batteries, they are cheap, lost instruments are
> > > > dangerous, lost OLC logs are maddening!
>
> > > > From experience.... now running 3 batteries..... saves me adding water
> > > > ballast! ;-)
>
> > > > Bob
>
> > > AMEN!
>
> > > My solution was to split the cockpit into two electrical busses, each
> > > with it's own 9AH battery. Either side can fail and I have enough
> > > "stuff" to get home (or finish a race...). Can also gang the busses
> > > so either battery can power all the cockpit.
>
> > > I have 3 batteries, one is always on the charger, and rotate the ones
> > > from the flight every evening - so I always have 2 fully charged
> > > batteries every flight. No special connectors on the batteries, so
> > > any standard size 7 - 9 AH "brick" with spade connectors will fit, if
> > > necessary.
>
> > > It's worked so far (8 years and counting...).
>
> > > I see there are some new technology batteries coming on the market for
> > > gliders (in S&G?) - maybe we are about to move on from our beloved
> > > lead bricks!
>
> > > Kirk
> > > 66
>
> > I replaced my lead acid 7 ah brick with a NiMh pack made up by a
> > supplier. The result is a pack that fits into the same battery holder
> > slot, is 30% lower in height, 50% lighter, runs at 14v nominal and
> > has a 9 Ah capacity. It was so succesfull that I replaced the second
> > 15 ah battery used to raise and lower the turbo with a similar pack
> > but of only 12ah but saving 7kg.
>
> > One other advantage is that they use a purpose built microprocessor
> > controlled charger that ensures they are fully charged and ready to go
> > even when left permanently connected.
>
> Same here, 10Ah NiMh battery dedicated to the transponder, two 5Ah
> packs for the instruments (one in the tail). Charger is putting out
> 2A and takes only about 2-4h after a normal day of flying to replenish
> the batteries. I built the packs myself from cells with tabs and paid
> only $80 for the large 10Ah pack, half of that for each of the small
> ones. No more lead-acid batteries! The weight savings mentioned by
> nimbusgb might be a bit aggressive, I'd say NiMh is about 60% lighter
> than the same lead-acid capacity battery.
> Herb

Sorry not 7kg but 7lb lighter than the big 18Ah (?) pack.I agree about
60% of the weight of the lead acids.

Ian

[nimbusgb]

On 24 Apr, 11:20, ContestID67 > wrote:
> I'd love to see some pictures of your NiMh creations.
>
> Can you send to me or upload somewhere likehttp://www.flickr.com.
>
> This would also be a great how to article for Soaring.
>
> john <at> derosaweb.com
>
> Thanks

Just as a matter of interest .....

I am flying OPA's at the moment ( other peoples aeroplanes ) and have
a portable setup with Colibri logger and Ipaq PDA all driven from a
LiPo Electric R/C aircraft flight pack. A12v pack with 2200ma/hr
capacity. The power to volume/weight ratio is great. The pack weighs
about 100g and is about the size of 6 cigarettes! It drives the setup
for about 6 hours with the pda on all the time.

Ian

[[email protected]]

On Apr 24, 9:58*am, nimbusgb > wrote:
> On 24 Apr, 11:20, ContestID67 > wrote:
>
> > I'd love to see some pictures of your NiMh creations.
>
> > Can you send to me or upload somewhere likehttp://www.flickr.com.
>
> > This would also be a great how to article for Soaring.
>
> > john <at> derosaweb.com
>
> > Thanks
>
> Just as a matter of interest .....
>
> I am flying OPA's at the moment ( other peoples aeroplanes ) and have
> a portable setup with Colibri logger and Ipaq PDA all driven from a
> LiPo Electric R/C aircraft flight pack. A12v pack with 2200ma/hr
> capacity. The power to volume/weight ratio is great. The pack weighs
> about 100g and is about the size of 6 cigarettes! It drives the setup
> for about 6 hours with the pda on all the time.
>
> Ian

I would never fly with LiPo on board. Let alone in someone elses ship.
I have quite a few of them for my R/C aircraft and have seen them at
their worst. Please be careful.

[Marc Ramsey[_2_]]

wrote:
> On Apr 24, 9:58 am, nimbusgb > wrote:
>>
>> I am flying OPA's at the moment ( other peoples aeroplanes ) and have
>> a portable setup with Colibri logger and Ipaq PDA all driven from a
>> LiPo Electric R/C aircraft flight pack. A12v pack with 2200ma/hr
>> capacity. The power to volume/weight ratio is great. The pack weighs
>> about 100g and is about the size of 6 cigarettes! It drives the setup
>> for about 6 hours with the pda on all the time.
>>
>> Ian
>
> I would never fly with LiPo on board. Let alone in someone elses ship.
> I have quite a few of them for my R/C aircraft and have seen them at
> their worst. Please be careful.

You don't fly with a cell phone or a PDA?

Marc

[[email protected]]

On Apr 24, 12:30*pm, Marc Ramsey > wrote:
> wrote:
> > On Apr 24, 9:58 am, nimbusgb > wrote:
>
> >> I am flying OPA's at the moment ( other peoples aeroplanes ) and have
> >> a portable setup with Colibri logger and Ipaq PDA all driven from a
> >> LiPo Electric R/C aircraft flight pack. A12v pack with 2200ma/hr
> >> capacity. The power to volume/weight ratio is great. The pack weighs
> >> about 100g and is about the size of 6 cigarettes! It drives the setup
> >> for about 6 hours with the pda on all the time.
>
> >> Ian
>
> > I would never fly with LiPo on board. Let alone in someone elses ship.
> > I have quite a few of them for my R/C aircraft and have seen them at
> > their worst. Please be careful.
>
> You don't fly with a cell phone or a PDA?
>
> Marc

Not with lithium Polymer batteries. Lithium Ion, yes. Lithium
Polymer, no.

[[email protected]]

On Apr 24, 12:30*pm, Marc Ramsey > wrote:
> wrote:
> > On Apr 24, 9:58 am, nimbusgb > wrote:
>
> >> I am flying OPA's at the moment ( other peoples aeroplanes ) and have
> >> a portable setup with Colibri logger and Ipaq PDA all driven from a
> >> LiPo Electric R/C aircraft flight pack. A12v pack with 2200ma/hr
> >> capacity. The power to volume/weight ratio is great. The pack weighs
> >> about 100g and is about the size of 6 cigarettes! It drives the setup
> >> for about 6 hours with the pda on all the time.
>
> >> Ian
>
> > I would never fly with LiPo on board. Let alone in someone elses ship.
> > I have quite a few of them for my R/C aircraft and have seen them at
> > their worst. Please be careful.
>
> You don't fly with a cell phone or a PDA?
>
> Marc

Have you ever seen an R/C LiPo cell? No hard case. It is essentially
a tin-foil-like bag of chemicals with a very high energy density.

[Marc Ramsey[_2_]]

wrote:
> On Apr 24, 12:30 pm, Marc Ramsey > wrote:
>> wrote:
>>> On Apr 24, 9:58 am, nimbusgb > wrote:
>>>> I am flying OPA's at the moment ( other peoples aeroplanes ) and have
>>>> a portable setup with Colibri logger and Ipaq PDA all driven from a
>>>> LiPo Electric R/C aircraft flight pack. A12v pack with 2200ma/hr
>>>> capacity. The power to volume/weight ratio is great. The pack weighs
>>>> about 100g and is about the size of 6 cigarettes! It drives the setup
>>>> for about 6 hours with the pda on all the time.
>>>> Ian
>>> I would never fly with LiPo on board. Let alone in someone elses ship.
>>> I have quite a few of them for my R/C aircraft and have seen them at
>>> their worst. Please be careful.
>> You don't fly with a cell phone or a PDA?
>>
>> Marc
>
> Not with lithium Polymer batteries. Lithium Ion, yes. Lithium
> Polymer, no.
>

What makes you think the "lithium ion" cells used in PDAs, laptops, and
cellphones are any different than the "lithium polymer" cells used in
R/C aircraft? Have you ever looked at the cells inside a PDA, or inside
the plastic cases used for cellphone or laptop batteries? Nearly all
are lithium polymer these days (and the R/C suppliers get theirs from
the same factories, which is why they are relatively cheap), although
the laptop manufacturers, thanks to some rather public incidents, are
just starting to switch over to newer, somewhat less flammable, battery
chemistries...

Marc

[[email protected]]

On Apr 24, 1:17*pm, Marc Ramsey > wrote:
> wrote:
> > On Apr 24, 12:30 pm, Marc Ramsey > wrote:
> >> wrote:
> >>> On Apr 24, 9:58 am, nimbusgb > wrote:
> >>>> I am flying OPA's at the moment ( other peoples aeroplanes ) and have
> >>>> a portable setup with Colibri logger and Ipaq PDA all driven from a
> >>>> LiPo Electric R/C aircraft flight pack. A12v pack with 2200ma/hr
> >>>> capacity. The power to volume/weight ratio is great. The pack weighs
> >>>> about 100g and is about the size of 6 cigarettes! It drives the setup
> >>>> for about 6 hours with the pda on all the time.
> >>>> Ian
> >>> I would never fly with LiPo on board. Let alone in someone elses ship.
> >>> I have quite a few of them for my R/C aircraft and have seen them at
> >>> their worst. Please be careful.
> >> You don't fly with a cell phone or a PDA?
>
> >> Marc
>
> > Not with lithium Polymer batteries. Lithium Ion, yes. *Lithium
> > Polymer, no.
>
> What makes you think the "lithium ion" cells used in PDAs, laptops, and
> cellphones are any different than the "lithium polymer" cells used in
> R/C aircraft? *Have you ever looked at the cells inside a PDA, or inside
> the plastic cases used for cellphone or laptop batteries? *Nearly all
> are lithium polymer these days (and the R/C suppliers get theirs from
> the same factories, which is why they are relatively cheap), although
> the laptop manufacturers, thanks to some rather public incidents, are
> just starting to switch over to newer, somewhat less flammable, battery
> chemistries...
>
> Marc- Hide quoted text -
>
> - Show quoted text -

Sorry, didn't mean to start an argument. Maybe my caution regarding
flying with R/C (foil bag) LiPo batteries is a little over the top. I
can live with erring on the side of caution. To each his own.

[Marc Ramsey[_2_]]

wrote:
> Sorry, didn't mean to start an argument. Maybe my caution regarding
> flying with R/C (foil bag) LiPo batteries is a little over the top. I
> can live with erring on the side of caution. To each his own.

I'm not trying to get into an argument either, just making the point
that most of us already carry several foil bag lithium polymer batteries
in our gliders. The original metal case lithium ion batteries haven't
been used in consumer products for years, mostly because we want
everything light (remember 8 lb laptops?).

R/C batteries have a high (explosive 8^) failure rate mostly due to the
various kinds of abuse they are subject to, incorrect charging,
continued use after being damaged in crashes, overly high discharge
rates, full short circuits, etc. If someone knows what they are doing,
there shouldn't be a problem. But, I agree, if you don't know, don't do
it. I, for one, wouldn't want a pack large enough to power a radio and
transponder in my glider...

Marc

[SoaringXCellence]

On Apr 24, 1:28*pm, Marc Ramsey > wrote:
> wrote:
> > Sorry, didn't mean to start an argument. Maybe my caution regarding
> > flying with R/C (foil bag) LiPo batteries is a little over the top. I
> > can live with erring on the side of caution. To each his own.
>
> I'm not trying to get into an argument either, just making the point
> that most of us already carry several foil bag lithium polymer batteries
> in our gliders. *The original metal case lithium ion batteries haven't
> been used in consumer products for years, mostly because we want
> everything light (remember 8 lb laptops?).
>
> R/C batteries have a high (explosive 8^) failure rate mostly due to the
> various kinds of abuse they are subject to, incorrect charging,
> continued use after being damaged in crashes, overly high discharge
> rates, full short circuits, etc. *If someone knows what they are doing,
> there shouldn't be a problem. *But, I agree, if you don't know, don't do
> it. *I, for one, wouldn't want a pack large enough *to power a radio and
> transponder in my glider...
>
> Marc

I have done the RC thing for over 45 years. I've observed that as the
use of LiPo cells have progressed the rate of failure has decreased.
Inspite of that I would also either use a metal cased cells or a pack
in a metal box if I were to use them in an aviation application.
Istalled in the PDA or Cell phone they have some puncture protection
and that seems to be one of the major hazards to their use.

On the same idea; the A123systems cells are metal cased and at $110
for six (2.3 Ah) of them is a pretty good deal as far as lithium cells
go. I'm planning on getting several "Developer Kits" to assemble
several packs for the glider. Four cells, each a little larger than a
AA Alkaline, means that I can get a pretty good serial/parallel
battery setup and fit the individual battery packs into small
spaces.

The BIG handicap is the cost; to assemble 3 packs will cost $220 plus
assembly and wiring, for a 7.2AH pack.

[Bill Daniels]

"SoaringXCellence" > wrote in message
...
On Apr 24, 1:28 pm, Marc Ramsey > wrote:
> wrote:
> > Sorry, didn't mean to start an argument. Maybe my caution regarding
> > flying with R/C (foil bag) LiPo batteries is a little over the top. I
> > can live with erring on the side of caution. To each his own.
>
> I'm not trying to get into an argument either, just making the point
> that most of us already carry several foil bag lithium polymer batteries
> in our gliders. The original metal case lithium ion batteries haven't
> been used in consumer products for years, mostly because we want
> everything light (remember 8 lb laptops?).
>
> R/C batteries have a high (explosive 8^) failure rate mostly due to the
> various kinds of abuse they are subject to, incorrect charging,
> continued use after being damaged in crashes, overly high discharge
> rates, full short circuits, etc. If someone knows what they are doing,
> there shouldn't be a problem. But, I agree, if you don't know, don't do
> it. I, for one, wouldn't want a pack large enough to power a radio and
> transponder in my glider...
>
> Marc

I have done the RC thing for over 45 years. I've observed that as the
use of LiPo cells have progressed the rate of failure has decreased.
Inspite of that I would also either use a metal cased cells or a pack
in a metal box if I were to use them in an aviation application.
Istalled in the PDA or Cell phone they have some puncture protection
and that seems to be one of the major hazards to their use.

On the same idea; the A123systems cells are metal cased and at $110
for six (2.3 Ah) of them is a pretty good deal as far as lithium cells
go. I'm planning on getting several "Developer Kits" to assemble
several packs for the glider. Four cells, each a little larger than a
AA Alkaline, means that I can get a pretty good serial/parallel
battery setup and fit the individual battery packs into small
spaces.

The BIG handicap is the cost; to assemble 3 packs will cost $220 plus
assembly and wiring, for a 7.2AH pack.

It would be cheaper to buy a pair of DeWalt 36V LiFePo4 power tool batteries
from eBay for around $150. Each pack contains 10 A123 Systems 3.6V 2.3AH
cells. A 4x5 pack would be a nice 14.4V, 11.5AH glider battery.

Bill D

[sisu1a]

On Apr 24, 5:52 pm, "Bill Daniels" <bildan@comcast-dot-net> wrote:
> "SoaringXCellence" > wrote in message
>
> ...
> On Apr 24, 1:28 pm, Marc Ramsey > wrote:
>
>
>
> > wrote:
> > > Sorry, didn't mean to start an argument. Maybe my caution regarding
> > > flying with R/C (foil bag) LiPo batteries is a little over the top. I
> > > can live with erring on the side of caution. To each his own.
>
> > I'm not trying to get into an argument either, just making the point
> > that most of us already carry several foil bag lithium polymer batteries
> > in our gliders. The original metal case lithium ion batteries haven't
> > been used in consumer products for years, mostly because we want
> > everything light (remember 8 lb laptops?).
>
> > R/C batteries have a high (explosive 8^) failure rate mostly due to the
> > various kinds of abuse they are subject to, incorrect charging,
> > continued use after being damaged in crashes, overly high discharge
> > rates, full short circuits, etc. If someone knows what they are doing,
> > there shouldn't be a problem. But, I agree, if you don't know, don't do
> > it. I, for one, wouldn't want a pack large enough to power a radio and
> > transponder in my glider...
>
> > Marc
>
> I have done the RC thing for over 45 years. I've observed that as the
> use of LiPo cells have progressed the rate of failure has decreased.
> Inspite of that I would also either use a metal cased cells or a pack
> in a metal box if I were to use them in an aviation application.
> Istalled in the PDA or Cell phone they have some puncture protection
> and that seems to be one of the major hazards to their use.
>
> On the same idea; the A123systems cells are metal cased and at $110
> for six (2.3 Ah) of them is a pretty good deal as far as lithium cells
> go. I'm planning on getting several "Developer Kits" to assemble
> several packs for the glider. Four cells, each a little larger than a
> AA Alkaline, means that I can get a pretty good serial/parallel
> battery setup and fit the individual battery packs into small
> spaces.
>
> The BIG handicap is the cost; to assemble 3 packs will cost $220 plus
> assembly and wiring, for a 7.2AH pack.
>
> It would be cheaper to buy a pair of DeWalt 36V LiFePo4 power tool batteries
> from eBay for around $150. Each pack contains 10 A123 Systems 3.6V 2.3AH
> cells. A 4x5 pack would be a nice 14.4V, 11.5AH glider battery.
>
> Bill D

Here's another source for LiFePo cells, that offer pre-fab batteries
of higher density/$ ($200/10AH as opposed to $220/7AH + assembly/
wiring) for although they claim not to be able to take on any new
customers, I bet they could be talked into coming off some:
http://www.powerstream.com/LLL.htm

Paul Hanson

[Udo]

I want to second Bill's comment.
A123 cells are also "much less" sensitive to charging error, as well
they can be discharged at a higher rate. They are 20% heavier
everything else being equal then the Polymer cells. They have no
memory and 1000 plus cycles. The last I heard the Dewalt pack of 10
cells can be had for about $100.00 but that was six month ago.
Udo




> I have done the RC thing for over 45 years. *I've observed that as the
> use of LiPo cells have progressed the rate of failure has decreased.
> Inspite of that I would also either use a metal cased cells or a pack
> in a metal box if I were to use them in an aviation application.
> Istalled in the PDA or Cell phone they have some puncture protection
> and that seems to be one of the major hazards to their use.
>
> On the same idea; the A123systems cells are metal cased and at $110
> for six (2.3 Ah) of them is a pretty good deal as far as lithium cells
> go. *I'm planning on getting several "Developer Kits" to assemble
> several packs for the glider. *Four cells, each a little larger than a
> AA Alkaline, means that I can get a pretty good serial/parallel
> battery setup and fit the individual battery packs into small
> spaces.
>
> The BIG handicap is the cost; to assemble 3 packs will cost $220 plus
> assembly and wiring, for a 7.2AH pack.
>
> It would be cheaper to buy a pair of DeWalt 36V LiFePo4 power tool batteries
> from eBay for around $150. *Each pack contains 10 A123 Systems 3.6V 2.3AH
> cells. *A 4x5 pack would be a nice 14.4V, 11.5AH glider battery.
>
> Bill D- Hide quoted text -
>
> - Show quoted text -

[sisu1a]

> > It would be cheaper to buy a pair of DeWalt 36V LiFePo4 power tool batteries
> > from eBay for around $150. Each pack contains 10 A123 Systems 3.6V 2.3AH
> > cells. A 4x5 pack would be a nice 14.4V, 11.5AH glider battery.
>
> > Bill D- Hide quoted text -
>
Here is a great resource site for info on converting DeWalt batteries:
http://www.slkelectronics.com/DeWalt/index.htm There is lots of
useful info that could potentially save someone from doing something
unintentional and unfortunate.

Paul

[nimbusgb]

On 25 Apr, 03:41, Udo > wrote:
> I want to second Bill's comment.
> A123 cells are also "much less" sensitive to charging error, as well
> they can be discharged at a higher rate. They are 20% heavier
> everything else being equal then the Polymer cells. They have no
> memory and 1000 plus cycles. The last I heard the Dewalt pack of 10
> cells can be had for about $100.00 but that was six month ago.
> Udo
>
> > I have done the RC thing for over 45 years. I've observed that as the
> > use of LiPo cells have progressed the rate of failure has decreased.
> > Inspite of that I would also either use a metal cased cells or a pack
> > in a metal box if I were to use them in an aviation application.
> > Istalled in the PDA or Cell phone they have some puncture protection
> > and that seems to be one of the major hazards to their use.
>
> > On the same idea; the A123systems cells are metal cased and at $110
> > for six (2.3 Ah) of them is a pretty good deal as far as lithium cells
> > go. I'm planning on getting several "Developer Kits" to assemble
> > several packs for the glider. Four cells, each a little larger than a
> > AA Alkaline, means that I can get a pretty good serial/parallel
> > battery setup and fit the individual battery packs into small
> > spaces.
>
> > The BIG handicap is the cost; to assemble 3 packs will cost $220 plus
> > assembly and wiring, for a 7.2AH pack.
>
> > It would be cheaper to buy a pair of DeWalt 36V LiFePo4 power tool batteries
> > from eBay for around $150. Each pack contains 10 A123 Systems 3.6V 2.3AH
> > cells. A 4x5 pack would be a nice 14.4V, 11.5AH glider battery.
>
> > Bill D- Hide quoted text -
>
> > - Show quoted text -

http://www.lange-aviation.com/htm/english/products/antares_20e/battery_system.html

Antares flys on Lithium Ion batteries. I have no problem with my light
current draw, aluminium boxed, low current consumption LiPo pack that
is always within eyesight in the cockpit.

At worst I can stuff it out of the clear view panel!

:)

Ian

[marika]

"Marc Ramsey" > wrote in message
t...
> wrote:
>>
>
> What makes you think the "lithium ion" cells used in PDAs, laptops, and
> cellphones are any different than the "lithium polymer" cells used in R/C
> aircraft? Have you ever looked at the cells inside a PDA, or inside the
> plastic cases used for cellphone or laptop batteries? Nearly all are
> lithium polymer these days (and the R/C suppliers get theirs from the same
> factories, which is why they are relatively cheap), although the laptop
> manufacturers, thanks to some rather public incidents, are just starting
> to switch over to newer, somewhat less flammable, battery chemistries...


>

very interesting


mk5000

"Okay, the main air ducts lead to the central system. From there I
can take any branch and drop into the lobby. It's about a 20-plus foot drop
so. I'll probably break my leg - maybe both, but that's okay. This is good.
This is a good plane. Somebody uh, give me a screwdriver. "--Mike Cannon:
Las Veas