Thank you very much for posting this. I use a product called a Battery Tender in the US. My wife kept telling me they do not have them in China and I my Chinese language skills are too poor to describe to the guys here. They kept giving me car battery chargers. I have made a little trickle charger from a 12V power supply but you can not leave it on unattended day in and day out as it does not know to slow down when the battery is fully charged. Your post just made my life easier as I can now show the wife. Two of your posts in two days have made me smile. Thanks