On Feb 24, 9:14*pm, Eric Greenwell wrote:
GM wrote:
The prices have dropped to a very affordable level; so have the
chargers/balancers. The weight savings are considerable. My 12V/7.5Ah
standard sealed gel-cell weighs 2.35kg (5.17lbs) and it lasts a few
days. *I found two 7.4V/5.0Ah units on e-bay that weigh in at 0.3kg
each (0.6kg or 1.32 lbs in total)

Why do you wish to save 1.75 kg/3.85 pounds? That small amount can not
possibly affect your glider's performance. I mean, my drinking water
weighs about 6 pounds.

--
Eric Greenwell - Washington State, USA (netto to net to email me)

- "Transponders in Sailplanes - Feb/2010" also ADS-B, PCAS, Flarmhttp://tinyurl.com/yb3xywl

- "A Guide to Self-launching Sailplane Operation Mar/2004" Much of what you need to know tinyurl.com/yfs7tnz

I agree the weight savings are irrelevant. I suspect any real interest
from Li or LiPo will be from reduced space requirements/ease of adding
more capacity and extreme capacity for very long flights etc including
low temperature operation in Wave (some LiPo have good low temperature
performance).

Still more hassle and risk than VRLA, and a lot of work to do well.

OTOH Antares flies on Li with lots of engineering to help make it
safe. I have no problem with the Antares approach, but homemade LiPo
packs and systems worry me (and I fly models with Li and LiPo, but
VRLA for the glider).


Darryl