My HTC desire won't turn on

My battery was on 1%. I connected charger but then my phone just turned off. I tried to reboot but nothing happened. Orange LED is blinking which means that battery is too low to boot the phone. I left my HTC on charger for 10 hours and LED is still blinking. I tried all combinations with power button and volume up/down buttons. Do you know what is the problem? Please help me! :)