If you charge it to 15V only you will have a total capacity low enough that it will not worth the money.
You can linearly low the output voltage with 3A/6A diode as it says on Peter millenaar page. There will be power dissipating on he diodes of course, but it's negligible. I do not recommend buck converters because if you don't study the switching frecuency the noise on the radio can be high.

My friend had the same low voltage issue on his lx 9070 and drove him to change the battery type.
If you treat them well you have a battery for 8 seasons.


--
Eric Greenwell - Washington State, USA (change ".netto" to ".us" to email me)
- "A Guide to Self-Launching Sailplane Operation"
https://sites.google.com/site/motorg...ad-the-guide-1
Good points, Eric.
I currently have room for and use two 12V LiFe batteries (K2) but I get low voltage warnings on my SN10b fairly early into the flight when keying the radio, a KTR72N. The batteries are only two seasons old. I may have some other, more power hungry equipment, like a Volkslogger functioning only as the GPS source, which may have a higher draw.
My goal is to get rid of the Volkslogger but in parallel, I was thinking about upgrading the batteries. However, that seems to be not as easy as cleaning up my panel.

Uli
'AS'