A laptop left on continuous charge, with a battery purchased online, has exploded in a Melbourne home, causing spot fires in a bedroom.

A woman in her 20s was injured but did not require hospital treatment after the fire broke out in her home in Canterbury, in Melbourne's east, on Sunday night.

The Metropolitan Fire Brigade (MFB) said it appeared the laptop overheated after being left charging and the explosion left debris around the bedroom.

The woman was able to put out the fire before the emergency services arrived on the scene.

The MFB said it recommended people only buy genuine computer components.