On Wednesday, December 9, 2015 at 2:44:04 AM UTC-8, wrote:

I agree about the necessity of a charge controller / regulator. I have been using this one for a number of years now with no problems:

http://www.jaycar.com.au/Ecotech/Sol...anels/p/AA0348

That charger is not advertised as having a mode for Lithium batteries of any type. Says it's ideal for SLA (sealed lead acid).

In most gliders, space for installing PV panels is limited, unless you're covering the wings, so if charging SLA, I'd rather opt for one of the several available MPPT (maximum power point tracking) controllers. MPPT's are up to 30% more efficient at charging lead acids than regular switching or pulse width modulating controllers.