EVO N150 battery problem

I have been having battery problems with my Compaq EVO N150 notebook. I last
used it about 4 months ago. The battery charged fine, and worked equally
well with the AC adapter.
However, when I tried to use it last week, the notebook would not turn on
with just the battery. I worked fine with the AC. So I left it charging
overnight, thinking it was just a low battery. However, the next morning, it
still would not power on with just the battery. And, when charging, the
charge indicator would be red for about 20 seconds, green for 3, and dark
for 1, before the whole cycle started again.
I wrote Compaq. They suggested a BIOS update, taking the battery out for 5
minutes, and a host of other "fixes". None of them worked.
When viewing the power meter in the Power Management section, the battery
says that it is charging, but always shows 0% charged.

Has anyone had any similar problems? I don't want to spend $180 for a new
battery if I do not need it, and the local computer repair shop wants $140
just to walk in the door.

Thanks in advance.

Jim