If you have one, you've been advised to stop using it immediately.
Sony say a non-removable battery pack built by Panasonic is to blame and, in a statement, they said: "The safety of our customers is of the utmost importance, so we are advising those with affected models to switch off the unit and discontinue use."
"We have provided customers with a simple tool to check the serial number to identify whether it is an affected model."
The Vaio Fit 11A has only been on sale since February, so it shouldn't be too big of a problem.
Affected European products are:
You should visit the Sony page regarding this problem by clicking here. There, you can leave your contact details and Sony will get in touch with you to discuss what to do next. Or, if you prefer, call their hotline on 0844 8466 555.