Battery Not Charging

Andy Harris wrote:

"Battery is an Earth-X ETX900, which apparently is the Rotax preferred model. "..

Actually, the Aerolithium 680Li-18Ah is the preferred model.

Andy Harris should probably have mentioned that represents the company that makes Aerolithium batteries...  

I understand why HE would prefer Aerolithium (after all, he is paid to say that), but the statement he appears to be contradicting is that Earth-X ETX900 is the ROTAX preferred model.  

To be honest, I've never heard that ROTAX has stated a preference for ANY specific battery, so I would love to see ROTAX-sourced data that indicates such a preference.  I've seen data showing that Earth-X is "approved" for use with ROTAX engines, but nothing that indicates a preference.  Anyone have such information?

Back in 2015 ROTAX has said this:

"All ROTAX aircraft engines can only be operated with Lithium-ion batteries if a suitable battery management system qualified by the aircraft manufacturer is used in the aircraft." 

... the key point being that not all Lithium batteries at that time had built in battery-management circuitry. (Although many modern batteries now do have a full suite of protection built in)

for full details, see  https://legacy.rotaxowner.com/si_tb_info/alertbulletins/asb-912i-005is.pdf