Where can I buy a dell vostro 1000 14.8 volt battery?

I own a dell vostro 1000 and I'm looking for new batteries for the laptop. But I only find batteries with 11.1 volts but the laptop battery has 14.4 volts

Ask:

1) Where to find a battery with 14.4 volts

2) it would do something if you use the 11.1 volt battery

Googled before? The volt number must not change otherwise the device gets rid of shame. What you mean is the mAh performance. So how long does the battery last

As an original spare part at Dell.