Aspire s7 turns off when on battery power

My Aspire s7 turns off immediately after being turned on when on battery power, even if the battery charged. I tried pressing on the battery reset, but that didn't work. Any suggestions? Thank you.

How old is the battery? Jack E/NJ

It's about four years old and has been problematic from the start. But shutting off as soon as I turn the computer on is a relatively new thing.

Like a car battery, your laptop battery reaches full voltage quickly indicating that its fully charged. But can no longer hold many charges to produce the ampere current (charges per second) also needed to actually run the machine for more than a few seconds. Sorry, the battery needs to be replaced. Jack E/NJ

Thanks. Is it relatively easy to replace it?

\What is the exact model of notebook?

Just remove the 11 screws from the lower case and separate it from the upper case. Remove 3 screws holding the battery to the upper case as shown in the image below, lift the battery up and disconnect the battery cable from the mainboard. Jack E/NJ 

Thanks, everyone. Meanwhile, someone suggested that I press in the battery reset hole, and so far that has worked. If the problem recurs, I'll try replacing the battery.

 You said in your first post "I tried pressing on the battery reset, but that didn't work. "  What changed? Jack E/NJ

The second time I tried it, I waited several minutes before turning the computer back on. I am getting a couple of hours use of it now, but then it does turn off suddenly even though it shows a lot of battery power left. 

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