By the way I am offering AC/DC adapter 12 VDC 5 amps now at $20. free mail.
It is very easy and cheap in China to buy Li-ion battery.
I realise that some of you guys use lead acid battery, which is big and becomes weak and weak. It seems to me that most of you find difficult to buy Li-ion battery
As it is not allowed to send battery abroad via post office, I am suppling AC/Dc adapter now.