Battery Charger

[[email protected]]

Hey there probably hasnt been a Battery thread for a few months so here
goes! A quick search of the group didnt find what I was looking for.
Im gonna be buying a a 12 Volt 8 Ah gel cell for the Cherokee to run
the fancypants electronics I got for christmas. Need a charger. The
place Im getting the battery from has a 12V 500 mAh and 12V 1 mAh
charger for the battery. Both are dual stage. They also have 3 stage
and unregulated. I think i remember conversation that the multiple
stages are better because it gives a fuller charge. whats the various
mAh ratings mean? charging speed? is slower better? Thanks!

[Paul Remde]

Hi,

I give some information about battery chargers on my Batteries page here:
http://www.cumulus-soaring.com/batteries.htm

Good Soaring,

Paul Remde
Cumulus Soaring, Inc.
http://www.cumulus-soaring.com

> wrote in message
oups.com...
> Hey there probably hasnt been a Battery thread for a few months so here
> goes! A quick search of the group didnt find what I was looking for.
> Im gonna be buying a a 12 Volt 8 Ah gel cell for the Cherokee to run
> the fancypants electronics I got for christmas. Need a charger. The
> place Im getting the battery from has a 12V 500 mAh and 12V 1 mAh
> charger for the battery. Both are dual stage. They also have 3 stage
> and unregulated. I think i remember conversation that the multiple
> stages are better because it gives a fuller charge. whats the various
> mAh ratings mean? charging speed? is slower better? Thanks!
>

[Richard[_1_]]

Chargers are inexpensive at Wal Mart and are 2 stage and shut off when
fully charged.

I know this isn't scientific but I wouldn't get all that excited about
batteries. I have been using 12v 7 amp/hr batteries with WalMart
Chargers for 6 years. I take the batteries home after every flight
and charge. The batteries are also inexpensive $20. I have been
getting good results on the batteries for 2 years and replace at that
time. Put a date on the battery. 200 + flying hours per year.

See http://www.automatedoutlet.com/product.php?productid=697

for the batteries 12 v 8 amp hr $20 + shipping, get a couple,
same size as the 12v 7 amp hr.

Richard
www.craggyaero.com



wrote:
> Hey there probably hasnt been a Battery thread for a few months so here
> goes! A quick search of the group didnt find what I was looking for.
> Im gonna be buying a a 12 Volt 8 Ah gel cell for the Cherokee to run
> the fancypants electronics I got for christmas. Need a charger. The
> place Im getting the battery from has a 12V 500 mAh and 12V 1 mAh
> charger for the battery. Both are dual stage. They also have 3 stage
> and unregulated. I think i remember conversation that the multiple
> stages are better because it gives a fuller charge. whats the various
> mAh ratings mean? charging speed? is slower better? Thanks!

[ContestID67]

I have been using the Deltran Battery Tender line of smart chargers for
years (club and personal) and have been very happy.

http://www.batterytender.com/

- John

[Dan D]

i wonder why no one uses those super thin solar cells attached to the wing
or tail surface and use batteries as a buffer and forget the overnight
charger altogether. search "powerfilm"
I dont know but probably someone out there has tried it?
I'd be interested to find out. seems like it would be easy to build these in
during construction and clearcoat over
the top. a built in power system. run all the gadgets, computer screens,
varios, gps, maybe even a transponder too.


> wrote in message
oups.com...
> Hey there probably hasnt been a Battery thread for a few months so here
> goes! A quick search of the group didnt find what I was looking for.
> Im gonna be buying a a 12 Volt 8 Ah gel cell for the Cherokee to run
> the fancypants electronics I got for christmas. Need a charger. The
> place Im getting the battery from has a 12V 500 mAh and 12V 1 mAh
> charger for the battery. Both are dual stage. They also have 3 stage
> and unregulated. I think i remember conversation that the multiple
> stages are better because it gives a fuller charge. whats the various
> mAh ratings mean? charging speed? is slower better? Thanks!
>

[[email protected]]

You would really not want to mess with trying to keep the flow over
these laminar or deal with other manufacturing issues with a critical
airfoil surface. Sticking the on the fuselage can probably get you
enough power for toys. Which is exactly what people do today.

Look at www.strobl-solar.com. Available as well installed by all major
glider manufactures. And many of the manufactures or their reps can
sell after market install kits or they are available from Strobl
direct. I'm in the process of having set installed on our club
DG-1000.

The PowerFilm are amorphous silicon, the Strobl are individual
crystalline silicon cells laminated between plastic sheets.
Crystalline silicon has a factor of several increase in efficiency
over amorphous, which if you look at the numbers will explains why the
Strobl panels are so much more efficient than the PowerFilm - even
with "wasted" space between the individual cells. The plastic laminate
is flexible enough to allow the sheets to curve to the glider surface.
They are bonded (3M VHB tape) onto the glider surface or recessed into
the surface during manufacture, which looks nice.

Amorphous panels are great for ground use since they are really
robust, can't shatter etc. Some can be rolled, up, etc. Unfortunately
the best of these was the UniSolar Flex 30 W panels that are no longer
in production. They were a nice strong heavy weight laminate and had
eyelets to attach cords to secure to a glider, say draped over a wing.
The PowerFilm ones are long and thin and the laminate is lighter and
therefore are more of a pain to secure to a glider and blow around in
the wind more than the UniSolar did. Still they are a good option for
ground charging if you want to secure something to the glider.

UniSolar still makes rigid panels that are amorphous silicon laminated
to a thin painted steel sheet in a rigid aluminum frame. If you weight
these down or have some where to mount them (not on the glider) they
make a great ground charging panel. I have this panel (frame removed)
stuck on the top of my Cobra trailer and works great for charging four
12 Ah batteries.

Some information on glider batteries, chargers and solar panels here:
http://www.darrylramm.com/glider-batteries

BTW on chargers, two main things to look for -

1. All the chargers you are likely to buy are dumb - including the
"smart chargers" - they have no idea of the battery's capacity. Too
high a relative charge rate can lead to evaopration of electrolyte
from the valve regulated lead acid (VRLA) batteries we all use. The
batteries pressure valves are usually designed to vent somewhere above
a few PSI and will do so if the battery is charged at too high a
current. There is very little electrolyte in these batteries, just
moist fiberglass mats between the plates. Too low a charge rate and
the batteries might not charge in time. A good charge current is
something in the ballpark of battery capacity in Ah divided by 5 or
10. Look for the charger's peak current or "bulk charge" current spec.

2. Look for a charger that talks about being for something like...
SLA, sealed lead acid, sealed, recombinant gas, VRLA, valve regulated
lead acid, and the charger should mention having a "float" stage. What
you care about here is the charger significantly backs off the charge
current (i.e. "floats" the voltage) as the battery gets near being
charged. The reason again is to avoid loss of electrolyte. Using large
"trickle" chargers designed for flooded batteries (i.e. standard car
style batteries) may cause batteries left on those chargers to lose
their electrolyte by evaporation.

Particualry older style "trickle" chargers, even those designed for
smaller flooded batteries, are probalby not what you want for VRLA
batteries as they will hold the voltage too high.

VRLA batteries self discharge so slowly you do not need to leave them
on a charger when not in use. So if you are not sure about the charger
take them off the charge after they have charged. Electrolyte venting
is also one of the reasons you want to keep the battery cool,
especially during charge.

I might disagree a little with Richard and encourage people to look
for brand name chargers with features like good status indicators,
self protection features etc, and to buy brand bame batteries, but to
Richard's point none of this is hard to do and batteries are cheap, so
if in doubt toss (recycle) them. And keep those transponders turned
on...


Darryl


On Feb 4, 9:25 pm, "Dan D" > wrote:
> i wonder why no one uses those super thin solar cells attached to the wing
> or tail surface and use batteries as a buffer and forget the overnight
> charger altogether. search "powerfilm"
> I dont know but probably someone out there has tried it?
> I'd be interested to find out. seems like it would be easy to build these in
> during construction and clearcoat over
> the top. a built in power system. run all the gadgets, computer screens,
> varios, gps, maybe even a transponder too.
>
> > wrote in message
>
> oups.com...
>
> > Hey there probably hasnt been a Battery thread for a few months so here
> > goes! A quick search of the group didnt find what I was looking for.
> > Im gonna be buying a a 12 Volt 8 Ah gel cell for the Cherokee to run
> > the fancypants electronics I got for christmas. Need a charger. The
> > place Im getting the battery from has a 12V 500 mAh and 12V 1 mAh
> > charger for the battery. Both are dual stage. They also have 3 stage
> > and unregulated. I think i remember conversation that the multiple
> > stages are better because it gives a fuller charge. whats the various
> > mAh ratings mean? charging speed? is slower better? Thanks!