Use these in airplanes to save some weight?

 We usually use two independently switchable batteries (at least I
 do)so the self-protection low voltage feature may not be a problem.

 http://eetweb.com/power-

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 <http://eetweb.com/power-

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 http://4xspower.com/products/

 Perry Mick

 That is the way Mike set up the RV4. Is 28 AmpHr (both batts.)
 enough for starting?

 Paul Lamar

 I currently use two Panasonic sealed lead-acid batteries. Just ordered
 replacements as the existing have been in place for many years. Digikey
 part number P049-ND, 28 AH each. I can independently switch in
 either orboth, but I always start and run on both. I think I did
 start it longago on one battery. Invoice from Digikey says 46
 lbs. shipping wt. forthe two batteries.

 Perry Mick

 I used a single 16 AH SLA for starting just fine. But with Li Ion
 it woulddepend on the "C" rating of the cells;  If you figure
 about 100A forstarting with your 28 AH pack, the C rating of the
 cells should be 4C orgreater. Otherwise you risk fire and very
 quickly degrading the pack.

 You can save some weight with Li ion, but the charging scheme
 that we usefor lead acids is unacceptable for li Ions and they
 will catch fire.  Andwith a pack that big, it will be a big fire.So you
would have to isolatethe battery pack and use a proper
 computer to charge it and regulate  inflowand outflow current and
 analize each individual cell  etc..

 Also, a 28 AH pack will cost over $200, sometimes WELL over that.

 I put the equivalent of a 48 AH pack into my skate board.  Great
 range andlow weight.  But you have to be careful with those
 things!  ALWAYS use acontrolling circuit board.

 -- David Leonard

 Turbo Rotary RV-6 N4VY
 http://N4VY.RotaryRoster.net
 http://RotaryRoster.net

 I have a sense that these LiOn cells would be rejected by your
 DAR asairworthy. They are highly regulated items for just
 transport on aircraft,let alone an integrated part of necessary
 systems. David makes very goodpoints about their different
characteristics.
 Your results may vary.
 C. Smith

Always had good results with NiCad batteries in RC cars.  There
 are some  U-tube videos of NiCad putting out very high levels of
 power.  The  charging requirements are not finniky like Lithium.

Dan F

 On an experimental, the DAR is not going to probably even know what
 kind of battery you use, nor is it his responsibility.  That
 inspection is more of a paperwork drill.  You may use Li Ion if you
 want as well.

 Ni Cads could not be hooked up to an aircraft  electrical system and
 charged like an SLA either.  The charging algorithm for NiCads and
 Ni Metal Hyd is the most difficult of all.  Li Ions are actually
 easy in terms of the computer knowing the state of charge... state
 of charge is directly related to voltage.  They wont work in a 12V
 system mostly because you must limit the charging current.  NiCad is
 the same, but at least they wont catch fire if you dont do it right.
 With NiCads, the charge state is not represented by the voltage.

 The charging computer must use a complex algorithm that looks at how
 current has changed with voltage (and preferably temperature) over
 time to figure out the charge state.  NiCad also has problems with memory.

 Li Ion are still much better energy/weight than NiCad too.

 But just use an SLA with your 12V system.  Even the Nissan Leaf has
 a 12V SLA that takes care of the 12V systems leaving the Ni Cads for
 go-power.  Nothing beats the price/current and ease of use of the
 Lead Acids..

 --
 David Leonard

 Turbo Rotary RV-6 N4VY
 http://N4VY.RotaryRoster.net
 http://RotaryRoster.net

 These are the Sealed Lead Acid batteries that fit Mike's battery box.

 BBBP12-12F2    12V 12AH AGM .250

 They are about $80 each at:

http://www.batteriesplus.com/**t-browseall.aspx<http://www.batteriesplus.com/t-browseall.aspx

 Mike used 2 in parallel for starting.

 Dave, please bring your hand held radio on the 10th. I have not
 bought the xcom yet. I had to spend some of the money I was saving
 to buy Robin an Asus Transformer tablet fo her birthday.


http://rerviews.cnet.com/**tablets/asus-eee-pad-**transformer/4505-<http://rerviews.cnet.com/tablets/asus-eee-pad-transformer/4505-
 3126_7-34467853.html

 Paul Lamar

Have you seen the BrailleBattery.com site.  Lithium batteries for drop in
use
with alternators. Motorsport and power sport apps.

Dale Davies


I dont think those batteries are meant to be plug and play.  Nowhere on
their site did I see anything mentioned about charging scheme.  But it does
state that the full charge voltage is 13.2 volts...  so what happens when
you put them in a 14V system?  Some claim to have a max current rating of
1800 amps on a 28 AHr battery... that would be a 64C rating... I don't think
so!!!!!  That battery also costs $2 AMUs... all to save about 10 lbs..

I think they are meant to be put in the system and used for the race, but
then removed and charged externally.